004049   RAO G S, ARASADA R C, SAHOO P R, KHAN I (Applied Geophysics Dep, Indian Institute of Technology, Jharkhand- 826 004, Email: vasugeos@gmail.com) : Integrated geophysical investigations in the Mudiyawas– Khera block of the Alwar basin of North Delhi Fold Belt (NDBF): Implications on copper and associated mineralisation. J Earth Syst Sci 2019, 128(6), 161.

Mundiyawas–Khera area of the Alwar basin in the North Delhi Fold Belt is well known for copper and associated gold mineralisation hosted within the felsic volcanic rocks. Gravity and magnetic surveys were conducted over the established mineralised blocks covering an area of ∼ 8 km² in the study regions and these data were interpreted using the Euler deconvolution and 2D potential field modelling to determine the subsurface geometry and depth extent of the ore body. The geophysical signatures in this area reveal three prominent anomalous zones in corroboration with the surface geology and drill hole data. Although basic/mafic rocks have not been found within the area, the observed strong residual gravity high (∼ 4.0 mGal) and residual magnetic high closures (∼ 90 nT) in the Mundiyawas block could be due to the cumulative effect of small-scale structural domes and the occurrence of sulphide mineralisation especially in the form of massive pyrrhotite. Moderate magnetic anomalies without appreciable gravity anomalies over the main copper-bearing zones in the Khera block are possibly due to the disseminated form, vein fillings and stringers of chalcopyrite, arsenopyrite and minor pyrrhotite hosted within the felsic volcanic rocks. The results of Euler depth solutions over these anomalous zones are found to vary from 50 to 250 m. Further, the subsurface geometry obtained across the Mundiyawas block through joint gravity and magnetic modelling constrained with drill hole information clearly depicts the presence of sulphide ore body having a width of 30–80 m within the carbon phyllite and tremolite-bearing dolomite. Combining the geophysical signatures noticed along the lithocontacts with the available geochemical and mineralogical observations of drill hole samples, we further confirm the strata-bound nature of sulphide mineralisation in the Mundiyawas–Khera area and it is controlled by both lithology and structural geometry of the host rocks.

9 illus, 42 ref

004027   GUPTA S, PRAMANIK S, SMITA, VERMA A K (Applied Mathematics Dep, Indian Institute of Technology, Dhanbad- 826 004, Email: snehamoy.pramanik@gmail.com) : A comparative analysis due to the effect of point source on generation of SH wave. J Earth Syst Sci 2019, 128(6), 160.

The propagation of SH wave in a heterogeneous initially stressed viscoelastic layer lying over a heterogeneous initially stressed orthotropic half-space due to a point source is analysed mathematically. The dispersion equation of SH wave is obtained for the propagation of SH wave in a specified model. The method of Green’s function and Fourier transformation is incorporated to obtain the dispersion equation. The curves of dispersion equation are sketched for various values of heterogeneous parameters and initial stress on angular frequency, phase velocity and damping velocity in respect of wave number. The dispersion equation is derived for some special cases which reduces to the classical equation of Lovetype wave. The present study reveals the effect of heterogeneous parameter and initial stress associated with both viscoelastic and orthotropic media.

23 illus, 1 table, 19 ref

004040   LU Y-Y, KE C-Q, JIANG H-J, CHEN D-L (Nanjing Univ, Nanjing- 210 023, Email: kecq@nju.edu.cn) : Monitoring urban land surface deformation (2004–2010) from InSAR, groundwater and levelling data: A case study of Changzhou city, China. J Earth Syst Sci 2019, 128(6), 159.

Land deformation caused by the overexploitation of groundwater has become a potential geological hazard in Changzhou, China. To reduce the potential damage from deformation disasters, it is quite necessary to monitor them. In this study, C-band ENVISAT ASAR synthetic aperture radar (SAR) datasets acquired from 2004 to 2010 were processed with the small baseline subset (SBAS) interferometric SAR (InSAR) method to investigate the spatial–temporal distribution of land deformation. Levelling survey data were used to assess the deformation accuracy measured by the InSAR method, and groundwater level data were used to analyse the incentives for deformation. The SBAS InSAR results found several subsidence regions in the Wujin district and the central part of the Zhonglou district. The annual deformation rate calculated from the C-band interferograms ranged from −65 to +35 mm/yr in the line of sight (LOS) direction, and the cumulative subsidence ranged from −0.35 to 0.13 m in the vertical direction. The levelling survey data show that the two measurements are generally consistent. Correlation analysis between the groundwater table and InSAR measurements at six groundwater well stations shows that groundwater recharges can cause land rebound within the Changzhou urban region. However, subsidence was also observed simultaneously with a rising water table, which might have been caused by the status of consolidation of the strata. Our study provides scientific evidence on the management of groundwater extraction and the assessment of land-subsidence hazard.

9 illus, 2 tables, 48 ref

004044   MUKHOPADHYAY B, MUKHOPADHYAY M, ELAWADI E, GHOSH U K, PRAMANIK K (Map and Cartography Div, Geological Survey of India, Kolkata- 700 016, Email: basabmukhopadhyay@gmail.com) : Cinder cone morphometry in relation to gravity anomaly zones in the Harrat al Birk and Asir foreland, SW Saudi Arabia. J Earth Syst Sci 2019, 128(6), 158.

The Harrat al Birk (HAB) of the alkali basalts of the post-Miocene age erupted through a thick Precambrian crust along the Red Sea coast. The 200 cinder cones scatter within HAB and three distinct Bouguer anomaly zones are identified as the coastal gravity high (CGH), axial gravity low (AGL) and a gravity high further east Jabal As-Sawda gravity high (JSGH). Interpreted satellite imagery for 150 sizeable cinder cones in three gravity anomaly zones (134 (90%) in CGH, 10 (6%) in AGL and 6 (4%) in JSGH) are morphologically analysed. The juvenile cinder cones (age <1Ma) are characterised by subvertical slope angles (<40^◦) with a variable average geomorphic slope, 27^◦–40^◦ in JSGH, 25◦ in AGL and 2^◦–15^◦ in CGH. The oldest cones of JSGH display a high H_co/W_co ratio with angular asymmetry at their base angles. The major feeder lineaments/faults are oriented NNW–SSE to NW–SE, and they supply volcanic material to cinder cones within a distance of 2 km. The results, when integrated with geological maps and gravity profiles, provide a probable root-plumbing system of the volcano edifice. HAB is the produce of the volcanic process from the source area in JSGH that hosts the major cinders, where the tertiary gabbroic dyke zone acts as a vertical magma sheet for the cinders.

14 illus, 2 tables, 35 ref

004060   SREEJITH K M, UNNIKRISHNAN P, RADHAKRISHNA M (Geosciences Div, Space Applications Centre, Ahmedabad- 380 015, Email: sreejith81@gmail.com) : Isostasy and crustal structure of the Chagos–Laccadive Ridge, Western Indian Ocean: Geodynamic implications. J Earth Syst Sci 2019, 128(6), 157.

The Chagos–Laccadive Ridge (CLR), a prominent linear aseismic ridge in the Western Indian Ocean is believed to be a trace of the R´eunion hotspot. In order to understand the mode of emplacement of this ridge and the nature of the underlying crust, we carried out three-dimensional (3D) flexural modelling and coherence analysis of satellite-derived gravity and bathymetry data along the ridge. The analysis revealed variations in Effective Elastic Thickness (T_e) along the CLR. While the northernmost part of CLR is associated with low T_e of 3 km with a subsurface to surface loading ratio (f) of 1, towards the south, the Maldive Ridge and the Chagos Bank have a fairly uniform T_e of 8–10 km with a very low loading ratio f of 0.1–0.2. We consider the Laccadive Ridge as a continental sliver possessing underplated magmatic rocks caused by the Reunion hotspot volcanism. The Maldive Ridge and the Chagos Bank appear to have emplaced on a lithosphere of intermediate strength possibly on the flanks of the Central Indian Ridge.

6 illus, 2 tables, 60 ref

004041   MAHMOUD S A E A (Nuclear Materials Authority, Cairo, Egypt, Email: dr.Soliman72@yahoo.com) : Geology, mineralogy and mineral chemistry of the NYF-type pegmatites at the Gabal El Faliq area, South Eastern Desert, Egypt. J Earth Syst Sci 2019, 128(6), 156.

The Gabal El Faliq area is located in the Eastern Desert of Egypt and belongs to the Wadi Hafafit–Wadi Ghadir fold belt. Lenses and dykes of rare metal-bearing pegmatites occur along major weak zones in the area (Wadi El Gemal strike-slip and its Riedel shears), by which they are structurally controlled. These pegmatites are mineralogically complex. Moreover, they are zoned, and the intermediate zones of the pegmatite varieties contain high amounts of zircon, fergusonite-(Y), columbite-(Fe), allanite-(Ce), xenotime-(Y), monazite-(Ce and Nd), thorite and gummite. These minerals carry Zr, rare earth element (REE), Nb, Ta, Th, U >Ta, F, and they are classified into rare-metal pegmatites, specifically, the niobium, yttrium and fluorine (NYF) enrichment family. The geochemistry aspects of these pegmatites indicate Zr up to 28,984 ppm, Hf up to 1171 ppm, REE up to 19,206 ppm, Nb up to 9962 ppm, Ta up to 152 ppm, U up to 565.5 ppm, Th up to 850 ppm and Ga up to 90 ppm. They were formed under an intracontinental tectonic setting from a basaltic magma similar to the oceanic island basalts (OIBs) contaminated with the crust. Consequently, this study could be used as a guide for the exploration of rare metals in similar regions of the world.

16 illus, 4 tables, 69 ref

004020   DUSUNUR-DOGAN D, UNER S (Geophysical Engineering Dep, Istanbul Technical Univ, Istanbul, Turkey, Email: dusunur@itu.edu.tr) : Numerical simulation of groundwater flow and temperature distribution in Aegean Coast of Turkey. J Earth Syst Sci 2019, 128(6), 154.

Geological studies indicate that one of the most important geothermal systems of Turkey is located in the western Anatolia. There are plenty of studies covering the geological, geophysical and modeling aspects on land. In this study, for the first time, we construct coupled numerical models of fluid flow and temperature offshore Gulf of Izmir and Seferihisar–Doganbey, using constraints from marine seismic data, which reveal pockmarks, mud volcanoes, and fluid vents. The numerical models were designed by taking into account of main tectonic structures such as Izmir Fault, Doganbey Fault, Tuzla Fault and Seferihisar Horst. It is found that hydrothermal circulation pattern is influenced by the combination of presence of faults, sediment thickness and seafloor bathymetry. The models here give new insights into the future studies on the possible fluid transport mechanisms.

5 illus, 2 tables, 69 ref

004036   KUMAR R, ANBALAGAN R (Punjab Engineering Coll, Chandigarh- 160 012, Email: rohananadi@yahoo.com) : Landslide susceptibility mapping of the Tehri reservoir rim area using the weights of evidence method. J Earth Syst Sci 2019, 128(6), 153.

This study was aimed to utilise important landslide causal factors for the delineation of the landslide susceptible area using the weights of evidence (WofE) method in the Tehri reservoir rim region on a macro scale. The Tehri reservoir extends up to 70 km and bounded by moderate to steep slopes. Landslide susceptibility mapping (LSM) is an essential measure for identifying the potentially unstable slopes bounding the reservoir. With the help of ancillary data, remote sensing imagery and a digital elevation model, 10 causative factors along with landslide inventory were extracted. Initially, the WofE model was applied to obtain the association between landslides and causative factors. The process gave the numerical estimate of correlation between landslides and causative factors by means of positive and negative correlation. Important factor attributes, potentially causing landslides, were identified based on high positive correlation values. Later, the posterior probability of landslide occurrence for each mapping unit was also computed using the WofE model. Posterior probability was divided into five relative susceptibility classes. Validation of the posterior probability map was carried out by using the prediction rate curve technique and a reasonable accuracy of 83 % was achieved. LSM of the Tehri reservoir rim area implicates unplanned road construction and settlements coupled with the reservoir slope settlement process for the present degradation of the geo-environmental system in that region.

8 illus, 4 tables, 56 ref

004034   KHOSHTINAT S, AMINNEJAD B, HASSANZADEH Y, AHMADI H (Civil Engineering Dep, Islamic Azad Univ, Roudehen, Iran, Email: aminnejad@riau.ac.ir) : Groundwater potential assessment of the Sero plain using bivariate models of the frequency ratio, Shannon entropy and evidential belief function. J Earth Syst Sci 2019, 128(6), 152.

The goal of the present research is to evaluate three bivariate models of the frequency ratio, Shannon entropy (SE) and evidential belief function in the spatial prediction of groundwater at the Sero plain located in west Azerbaijan, Iran. In the first phase, well locations with groundwater yields >11 m³/hr were identified (75 well locations). Ten groundwater conditioning factors affecting the occurrence of groundwater, namely, altitude, slope degree, curvature, slope aspect, rainfall, soil, land-use, geology and distance from the fault and the river, were selected for modelling. Finally, the groundwater potential map results were drawn from three implemented models and they were validated using testing data by area under the receiver operating characteristic curve (AUC). The AUCs of these models were 0.84, 81 and 85 %, respectively. The results of the current study demonstrated that these models could be successfully employed for spatial prediction modelling. Moreover, the results of the SE model demonstrated that the most and the least important factors in groundwater occurrences in the area under study were altitude, curvature and rainfall, respectively. The results of this study are helpful for the Regional Water Authority of Urmia and the decision makers to comprehensively assess the groundwater exploration development and environmental management in future planning.

6 illus, 3 tables, 57 ref

004031   KATTAN Z (Geology Dep, Atomic Energy Commission of Syria, Damascus, Syrian Arab Republic, Email: cscientific5@aec.org.sy) : Factors controlling stable isotopes variability in precipitation in Syria: Statistical analysis approach. J Earth Syst Sci 2019, 128(6), 0151.

The major characteristics of the stable isotopes (¹⁸O and ²H) and deuterium excess (d-excess or d) of rainfall samples collected from 16 stations during two periods (1989–1993 and 2003–2006) were statistically analysed to understand the factors controlling the temporal and spatial isotope variability in precipitation (P) in Syria. Rainfall waters at the mountainous regions are remarkably the most depleted in heavy stable isotopes, with also high d-excess values (d>20⁰/₀₀). The enriched rainfall waters (lower d-excess values), mostly referring to coastal and some inland areas, are subject to the evaporation of falling raindrops. Rainfalls at the southern stations have impressively the highest d-excess values (d>22⁰/₀₀), likely because of intensive interactions with the Mediterranean Sea (MS) moistures. The temperature (T) effect, shown by an average δ¹⁸O gradient of ≈0.34 ± 0.03⁰/₀₀/ ^◦C, is very close to the Global Network for Isotopes in Precipitation value (0.3⁰/₀₀/ ^◦C). The altitude effect, represented by a δ¹⁸O gradient of −0.18 ± 0.03⁰/₀₀/100 m, fits well with the range given for most Mediterranean countries. Relative humidity (RH) and P-amount effects are characterised by an isotopic depletion, with a notable rise in the d-excess value with P and RH increases. The seasonal effect is shown by depleted δ18O and δ²H values during December–February and enriched δ¹⁸O and δ²H values at the end of April, with frequently low d-excess values (<8⁰/₀₀). T parameter seems to be the major factor that strongly controls the variability of the stable isotope compositions of P in Syria. The moisture from the MS and secondary evaporation conjunctly play additional roles, but of less importance than the T effect.

11 illus, 7 tables, 68 ref

004062   TIWARI S K, BISWAL T K (Earth Sciences Dep, Indian Institute of Technology Bombay, Mumbai- 400 076, Email: sudheer030192@gmail.com) : Palaeostress and magma pressure measurement of granite veins in the Neoproterozoic Ambaji granulite, South Delhi terrane, Aravalli–Delhi mobile belt, NW India: Implication towards the extension-driven exhumation of the middle–lower crustal rocks. J Earth Syst Sci 2019, 128(6), 150.

Neoproterozoic Ambaji granulite, in the South Delhi terrane (SDT) of the Aravalli–Delhi mobile belt (ADMB), is multiply deformed at different stages of its exhumation from the middle–lower crust. It was intruded by four phases of granites, G₀₋₃, of which the G₃ was syntectonic with brittle shearing. The orientation of the G₃ granite veins was used, in this paper, to measure the palaeostress and magma pressure during its intrusion. The G₃ granite has a porphyritic texture with quartz, microcline and biotite minerals and contains magmatic foliation; biotites are aligned oblique to such foliation, suggesting the syntectonic intrusion of the granite with normal faulting. Stereoplot of the poles of the granite veins shows concentration in the NW and SW quadrants and lack data over an elliptical area at the centre, indicating a girdle pattern. This implies that the magma pressure P_m > σ₂, compression σ1 was vertical and extension σ₃ was NW–SE horizontal. Values of θ₂ = 16 ^∘ and θ₃ = 40^∘ were obtained from the stereoplot, used to calculate stress ratio Φ = 0.81, driving pressure R′ = 0.92 and the construction of the 3D Mohr plot for P_m and principal stresses. Result suggests that the G₃ granite intruded under extensional tectonics that probably contributed to the exhumation of the Ambaji granulite.

5 illus, 59 ref

004057   SINGH D, KUMAR A, SHEKHAR M S, GARG S (Snow and Avalanche Study Establishment, Chandigarh- 160 036, Email: dan @rediffmail.com) : The impacts of the approaching western disturbances (WDs) on the surface meteorological variables over the north-west Himalaya (NWH), India. J Earth Syst Sci 2019, 128(6), 149.

Eastward-moving upper air troughs in the subtropical westerlies, commonly known as the western disturbances (WDs) in the Asian subcontinent, are primary sources of precipitation over the north-west Himalayan (NWH) region and the northern plains of India during winter. Many simulation case studies with the help of numerical weather prediction models and a few observational case studies have been conducted to understand the spatial structure, dynamics, energy and weather associated with the WDs over the NWH in the past. However, studies using in situ observations on the impacts of the approaching WDs on various surface meteorological variables at a local scale in the high-altitude mountainous regions of the NWH are lacking. The objectives of this study are to examine the impacts of the approaching WDs on various surface meteorological variables for 11 stations in the NWH and the associated precipitation amount in a 24-hr time interval. Changes (departures) in the values of various meteorological variables are examined on the first precipitation day of the occurrence of active WDs to study the impacts of the approaching WDs and the associated precipitation amount in the 24-hr time interval which are found to depend on the altitude and geographic location of a station. The mean drop in the maximum and ambient air temperatures are found to be 2.0^◦ and 0.7 ^◦C, respectively, while the mean rise in the minimum air temperature was found to be 0.8 ^◦C. A mean drop in the surface atmospheric pressure and a mean increase in the relative humidity are found to be 0.9 hPa and 19.5 %, respectively, in a 24-hr time interval. The mean precipitation amount and mean maximum precipitation amount associated with the active WDs in the 24-hr time interval are found to be 8.9 and 68.8 mm, respectively. The results are briefly discussed in the paper. The findings of this study can be useful for operational weather forecasting and a selection of precursor variables for developing a real-time local scale weather forecast model(s) for remote areas of the NWH for the winter season.

5 illus, 3 tables, 50 ref

004058   SINGH J, THAKUR M (Panjab Univ, Chandigarh- 160 014, Email: mahesh09@gmail.com) : Landslide stability assessment along Panchkula–Morni road, Nahan salient, NW Himalaya, India. J Earth Syst Sci 2019, 128(6), 148.

We report the slope stability analysis of three vulnerable sites (S1, S2 and S3) within the lower Siwalik along the Panchkula–Morni road section in the Nahan salient, north-western Himalaya. Kinematic analysis of joint data was conducted to understand the different modes of failure. Rock mass classification techniques like rock mass rating, slope mass rating (SMR) and continuous SMR were used for stability classification and the factor of safety was calculated using stability charts. At site S1, the instability is controlled by the orientation of the discontinuity joint J1 which is parallel to the bedding and at site S2, the slope fails due to the wedge. The Umri landslide site S3 is the product of a damage zone by the normal faults which intersect at joint J3; a wedge is formed which falls in the critical zone. The damage zone in the Umri landslide greatly affects the porosity and permeability of the rockmass and acts as a pathway for the percolation of water during rainfall which reduces effective stress. The slope failures are tectonically controlled results due to the high slope angles, structural discontinuities like joints and faults and structural damage zones associated with the faults.

12 illus, 8 tables, 65 ref

004048   RAHMAN S, ISLAM A K M S, SAHA P, TAZKIA A R, KRIEN Y, DURAND F, TESTUT L, ISLAM G M T, BALA S K (Bangladesh Univ of Engineering and Technology, Dhaka-1000, Email: akmsaifulislam@iwfm.buet.ac.bd) : Projected changes of inundation of cyclonic storms in the Ganges–Brahmaputra–Meghna delta of Bangladesh due to SLR by 2100. J Earth Syst Sci 2019, 128(6), 145.

Almost every year, Bangladesh experiences disasters such as tropical cyclones, storm surges, coastal erosion or floods. Tropical cyclones originate from the North Indian Ocean and often cause devastating flood inundations in Bangladesh. Storm surges of the Bay of Bengal (BOB) are larger compared to other regions of the world for similar cyclones due to amplification by the shallow water depth, huge continental shelf and convergent coastlines. This scenario of inundation for such storm surges in the future when the sea level rise (SLR) occurs due to global warming will be different from the present. The densely populated coastal region of Bangladesh is likely to become more vulnerable in the future due to SLR. Disaster risks can be reduced if storm surges can be predicted well ahead. To assess the possible changes of inundation in the future, a widely used coastal model, Delft3D, has been applied for this BOB region. The model has been validated for the storm surge of three recent devastating cyclones, namely, Sidr, Aila and Roanu in the southern coast of Bangladesh. The validated model has been run to produce inundation maps and statistics for cyclonic storm surges such as Sidr, Aila and Roanu and probable SLR. Three possible SLR boundary conditions are chosen from the business-as-usual climate scenario representative concentration pathway 8.5 with values of 0.5 m (lower limit), 1 m (upper limit) and 1.5 m (extreme case, considering the subsidence and a rapid collapse of the Antarctic ice sheet). It is found that a category 4 cyclone such as cyclone Sidr would inundate 2.6 %, 3.67 % and 5.84 % of the area of the country if the SLR is 0.5, 1 and 1.5 m, which will affect the livelihood of nearly 4.1, 7.0 and 9.1 million people of Bangladesh, respectively. It will also inundate up to 21.0 %, 42.1 % and 65.1 % of the Sundarbans mangrove forest, which will undoubtedly affect the ecology of this unique ecosystem.

4 illus, 2 tables, 32 ref

004043   MODAK A, SHEEL V, MONTMESSIN F (Physical Research Laboratory, Ahmedabad- 380 009, Email: varun@prl.res.in) : Retrieval of Martian ozone and dust from SPICAM spectrometer for MY27–MY28. J Earth Syst Sci 2019, 128(6), 144.

Ozone (O₃) is important in the stabilisation of CO₂ in the Martian atmosphere and thus it is important to study the spatio-temporal variability of O₃. We retrieve two years of total columnar O₃ from raw spectral data provided by the SPectroscopy for the Investigation of the Characteristics of the Atmosphere of Mars (SPICAM) instrument aboard the Mars Express. The seasonal variability is studied in tropical, mid- and high latitudes and is compared with simulations by a photochemical coupled general circulation model (GCM). The high latitudes exhibit the largest seasonal variations in O₃, with a winter high and a summer low and a comparison with GCM results is good in general. We have studied the correlation of O₃ with dust, retrieved simultaneously from SPICAM observations. In southern tropical latitudes, the columnar O₃ is seen to increase during a global dust storm year (Martian year (MY) 28) compared to the O₃ column values during a year without global dust storm (MY27), although the water vapour column between these years remains unchanged. This indicates the radiative impact of dust on O₃ and its retrieval. We also study the ozone–carbon monoxide correlation as a tracer of dynamics. The dynamical contribution to the O₃ column is found to be the highest during winter over the southern polar region.

11 illus, 47 ref

004051   RAY R, KHONDEKAR M H, GHOSH K, BHATTACHARJEE A K (Electronics and Communication Engineering Dep, Dr. B C Roy Engineering Coll, Durgapur- 713 206, Email: ray.rajdeep78@gmail.com) : Complexity and periodicity of daily mean temperature and dew-point across India. J Earth Syst Sci 2019, 128(6), 143.

The complexity of temperature and dew-point fluctuations across India are being investigated and analyzed with the help of recurrence plots (RP) and recurrence quantification analysis (RQA). The results firmly state that both data sets is non-linear, non-stationary and deterministic. Hilbert–Huang transform and an efficient peak detection algorithm (integral method) have been used to detect the underlying periodicity (above 95 % CL) within these two signals. The nature of the complexity and the derived periods of these two weather variables show that there are significant impact of the local geographical topology and global atmospheric fluctuations on the overall pattern and fluctuation of the temperature and dew-point profile across India.

1 illus, 4 tables, 35 ref

004054   SARMA V V S S, SRINIVAS T N R, KUMARI V R, PRASAD M H K, DALABEHERA H B, SATYANARAYANA U, RAO G D, RAO D B, PAUL Y S, MURTY V S N, et al. (CSIR- National Institute of Oceanography, Visakhapatnam- 530 017, Email: rajaniwilliams@gmail.com) : Suppressed biological production in the coastal waters off Visakhapatnam, India under the impact of the very severe cyclonic storm Hudhud. J Earth Syst Sci 2019, 128(6), 142.

Tropical cyclones generally enhance biological production due to the increase in nutrients input due to vertical mixing. In contrast, the very severe cyclonic storm (VSCS) Hudhud decreased primary production due to the strong stratification associated with torrential rainfall and high suspended load from the major city where the cyclone made landfall. The study region received nutrients from the cold core eddy and coastal upwelling in the offshore and inshore regions, respectively, during pre-cyclone period and the same was suppressed under the influence of cyclonic winds led to convergence by shoreward Ekman transport. The land run-off brought nutrients to the coast during cyclone Hudhud; however, their concentrations were less than that during other cyclones (Orissa supercyclone, Sidr and Phailin). Such low nutrient levels resulted from the VSCS Hudhud crossing the urban region (Visakhapatnam city) whereas other cyclones crossed the coast over fertile agricultural lands which led to high nutrients input associated with phytoplankton blooms. Therefore, the biological response to a cyclone not only depends on the intensity of the cyclone but also on the region of the land it crosses.

5 illus, 1 table, 28 ref

004066   YAGHOUBI B, HOSSEINI S A, NAZIF S (Water Engineering Dep, Islamic Azad Univ, Kermanshah, Iran, Email: snazif@ut.ac.ir) : Monthly prediction of streamflow using data-driven models. J Earth Syst Sci 2019, 128(6), 141.

The estimation of river run-off is a complex process, but it is of vital importance to the proper operation of reservoirs, the design of hydraulic structures, flood control, drought management and the supply of water and electricity. The high uncertainty in rainfall–run-off modelling and lack of data has made the development of rainfall–run-off models with acceptable levels of accuracy and precision challenging. Furthermore, the rainfall–run-off models commonly do not provide an explicit relationship between run-off and other variables to be used for run-off-related investigations. To overcome the knowledge and information shortage in rainfall–run-off modelling, data-driven models have been used instead of conceptual models for the development of rainfall–run-off models. In this paper, three data-driven models, the genetic algorithm-support vector regression (GA-SVR), genetic algorithm-artificial neural network (GA-ANN) and the group method of data handling (GMDH) have been used to predict the monthly run-off of the Gavehroud basin. Their performances are compared with a conceptual hydrological model (HYMOD) whose parameters are calibrated using the GA. To this end, the monthly data on precipitation, temperature and run-off at the Gavehroud basin over 49 yr (1960–2009) were analysed. Evaluation of the results using performance evaluation indicators showed that the hybrid model of GA-SVR provided better accuracy in predicting the nonlinear behaviour of flow data than the GA-ANN, GMDH and HYMOD.

9 illus, 4 tables, 35 ref

004061   SRINIVAS K N S S S, KISHORE P P, RAO D V S (CSIR– National Geophysical Research Institute, Hyderabad- 500 007, Email: srinivas.ngri@gmail.com) : The geological site characterisation of the Mandla region, Eastern Deccan Volcanic Province, Central India. J Earth Syst Sci 2019, 128(5), 139.

Detailed geological studies were carried out on the basaltic sequences along the Jabalpur–Niwas, Jabalpur–Chutka and Jabalpur–Mandla traverses covering an area of about 12 km×15 km to characterise various basaltic lava flows and their behaviour on seismotectonics and geodynamic setting of their formation in the Mandla region of the Eastern Deccan Volcanic Province (EDVP). The studies involve an analysis of the satellite images for the identification of lineaments/faults and field geological studies consisting of geological controls such as ground check, thickness of fractures and orientation along the acknowledged lineaments/faults. The results of the present research comprising 65 lineaments/faults mainly belonging to two geometric groups, minor and major dominantly in the NW–SE and the NE–SW and altered strata varying lithology (weathered to compact basalts) are recognised in the study area. Based on their extent, 57 lineaments have been classified as minor (<100 km) trends in three different orientations, i.e., NNE–SSW, ESE–WNW and ENE–WSW, whereas 8 lineaments were classified as intermediate (300–100 km) trends in NNE–SSW. No major (>300 km) lineaments are noticed in the study region. The field geological investigations have facilitated the recognition of 10 flows with different characteristic features and a variety of volcanic structures such as columnar, vesicular, amygdaloidal, inflated pahoehoe lava flows and red bole interflow horizons have been documented. Basement rocks of these Deccan basalt lavas are represented by Tirodi Biotite gneisses, quartzite, quartz–mica schists and crystalline limestone in the SE part of the study area of the Mandla region. The present study will help evaluate the localised site characterisation for urban planning and setting up major civil structures.

6 illus, 3 tables, 69 ref

004032   KHARYA A, SACHAN H K, SANTOSH M, SINGH S K, TIWARI S K (Wadia Institute of Himalayan Geology, Dehradun, Uttarakhand, Email: hksachan@wihg.res.in) : Isotopic fingerprinting of fluid circulation at the terminal stage of the Himalayan orogeny: An example from the Himalayan forearc basin, Indus Tsangpo suture zone, Ladakh, India. J Earth Syst Sci 2019, 128(5), 138.

Quartz and calcite veins are omnipresent in the Indus basin sedimentary rocks (IBSRs) of the Indus Tsangpo suture zone (ITSZ) which were formed by the accumulation of sediments derived from both sides of the tectonic plate. These veins appear to have formed just after the sediment diagenesis and were deformed together with the IBSR. The veins were studied for their rare earth elemental and isotopic geochemistry (C–O–Sr–Pb). The light rare earth element/mid rare earth element with an Eu/Eu* ratio of the veins (quartz and calcite) is >1 for the northern side (Tibetan side) and <1 for the southern side, indicating a mantle/magmatic and marine-related fluid source, respectively. The carbon, oxygen and strontium isotopes range from −14⁰ /₀₀ to −1⁰ /₀₀ VPDB, +5.7⁰ /₀₀ to +24.9⁰ /₀₀ Vienna standard mean ocean water and 0.7056 to 0.7099, respectively. The Sr–O mixing model points towards the mantle enriched fluid on the northern side of the IBSR, whereas on the southern side, the fluid was nearly marine. The intermixing of the fluid took place in the middle part of the Indus basin sediments comprising a mixed litho-unit succession. Similar characteristics of vein fluids with the host rocks indicate the derivation of fluids from the associated host IBSR, further substantiated by the lead isotopic systematics.

7 illus, 3 tables, 58 ref

004055   SCHARFENBERG L, JANDAUSCH S, ANETZBERGER L, REGELOUS A, SHARMA K K, WALL H D (Friedrich-Alexander Univ, Erlangen, Germany, Email: lars.scharfenberg@fau.de) : Differences in natural gamma radiation characteristics of Erinpura and Malani granites in NW India. J Earth Syst Sci 2019, 128(5), 137.

In NW India, large volumes of exposed Neoproterozoic basement rocks are formed by two magmatic suites, Erinpura granites as a late thermal event with respect to the ∼1 Ga Delhi Orogeny and the younger Malani igneous suite (770–750 Ma). Average uranium and thorium equivalent concentrations (in ppm) inferred from spectroscopic gamma radiation survey are higher in Malani rocks (Th 47.33 ppm and U 6.95 ppm) as compared to the Erinpura granites (Th 33.55 ppm and U 4.77 ppm). These values are considerably above the granite world average (Th 14.8 ± 13.2 ppm; U 3.93 ± 3.27 ppm). High U (up to 19 ppm) and Th (up to 88 ppm) in some Malani granites and a constant Th–U ratio of 7 points to a high degree of fractionation of the felsic magma. Higher radioelement concentration in the east (Mirpur granite) as compared to the west (Jaswantpura granite) is substantiated by geochemical data. Areas to the west and east of the Sirohi frontal thrust show differences, most likely a consequence of anatexis in the eastern sector. A high linear correlation between inductively coupled plasma mass spectrometry and gamma-ray data underlines the suitability of in-situ measurements for the determination of U and Th concentrations during a field survey providing basic information for future petrogenetic and risk-hazard studies in this granitic terrain.

10 illus, 2 tables, 73 ref

004068   ZEINALI B, TEYMOURI M, ASGHARI S, MOHAMMADI M, GUPTA V (Physical Geography Dep, Mohaghegh Ardabili Univ, Ardabil- 09141549147, Email: Zeynali.b@uma.ac.ir) : A study of frost occurrence and minimum temperatures in Iran. J Earth Syst Sci 2019, 128(5), 134.

In this research, the frequency of frost is analysed from 95 synoptic stations for the period 1990–2015. This information was categorised by a fuzzy c-approach clustering algorithm and indicated that Iran is classified into five clusters with the aid of the frost-occurrence frequencies. The greatest frequency of days with frost prevalence is located in Cluster 1 that consists of Sarab station with an average annual frequency of 141.1 days over the period 1990–2015. The least frequent is found in Cluster 5 that consists of the stations positioned along the south and north coasts. Spatial association for the frequency of incidence of frost days also includes a dependence on elevation and latitude of stations, as well as their situation inside the course of external synoptic systems, bodily and geomorphological features and local climate. Also, a study of daily minimum temperature displays a widespread warming trend at some stage during this period, and has discovered an increase in the index of the number of tropical nights, warmest nights and coldest nights and decreasing trends have been determined in the number of frost days, cool nights and cold spell period index over most regions of Iran.

7 illus, 2 tables, 38 ref

004024   FATHI M, AZADI M, KAMALI G, MESHKATEE A H (Atmospheric Science and Meteorological Research Center, Tehran, Iran, Email: azadi68@hotmail.com) : Improving precipitation forecasts over Iran using a weighted average ensemble technique. J Earth Syst Sci 2019, 128(5), 133.

In this paper, the ensemble-weighted mean (ENSWM) technique is experimented for improving 24- to 72-hr precipitation forecasts over Iran during autumn and winter 2011 and 2012. The ensemble prediction system (EPS), used in this research, consists of nine different configurations of the weather research and forecasting model. In this technique, weights for each ensemble member at each grid point are assigned on the basis of the correlation coefficient (CC) between ensemble members and observed daily rainfall during a training period. Apart from ENSWM, precipitation forecasts using the simple ensemble mean (ENSM) are also generated and compared. Results showed that, in general, the forecast errors are relatively high along the coasts of the Caspian Sea in northern and at the Zagros mountainous areas located in western Iran. The skill of the rainfall forecasts of the ENSWM is examined against ENSM and individual members of the ensemble. The 24- to 72-hr forecasts are evaluated using common statistical scores including root mean-squared error (RMSE), and anomaly CC (ACC) for continuous forecasts and probability of detection (POD) score and threat score for categorical forecasts. The comparison reveals that the ENSWM is able to provide more accurate forecast of rainfall over Iran by taking the strength of each constituent member of the ensemble. It has been further found that the precipitation forecast skill of ENSWM is higher than ENSM and each ensemble member in the short-range time scale over Iran. The rainfall prediction skill over Iran was improved significantly using the weighted ENSWM technique. Results clearly show the advantage of using an EPS for the prediction of precipitation over the country vs. a single deterministic forecast for operational purposes. The RMSE of 24-, 48- and 72-hr forecasts in ENSWM relative to ENSM is reduced by 2, 2 and 5 %, respectively. The CC increased by 15 % in the ENSWM relative to ENSM.

8 illus, 1 table, 35 ref

004052   REDDY S K K, SAHADEVAN D K, GUPTA H, REDDY D V (CSIR–National Geophysical Research Institute, Hyderabad- 500 007, Email: harishgupta78@gmail.com) : GIS-based prediction of groundwater fluoride contamination zones in Telangana, India. J Earth Syst Sci 2019, 128(5), 132.

Groundwater is the only perennial water resource available to rural communities, especially in semi-arid regions. This study aims to provide an overview of fluoride-contaminated groundwater in the Telangana, India, by predicting potentially affected areas. The prevalence of endemic fluorosis in different parts of Telangana has been widely reported. Therefore, it is necessary to demarcate the fluoride-affected areas to adopt the remedial measures. In this context, the available information on related environmental variables such as geological settings, hydro-morphological inputs, climatic information and soil properties have been integrated as thematic layers in an ArcGIS environment. The thematic layers and their features were assigned with suitable weights, which were normalised using the analytic hierarchy process to obtain final ranks and the weighted overlay analysis method was carried out to delineate the potential fluoride contamination (PFC) zones. The entire state was classified into four broad categories, i.e., very high (17.6 %), high (15.8 %), medium (32.7 %) and low (33.9 %), in terms of groundwater fluoride enrichment. A comparison of the output map and the reported data indicates that the PFC zone model could explain 68.7 % of fluoride variation. This study is the first such attempt to offer a regional-scale PFC zone for an entire state and offers a first-hand insight into the severity of fluoride contamination.

7 illus, 4 tables, 72 ref

004028   HOSSEINIZADEH A, ZAREI H, AKHONDALI A M, SEYEDKABOLI H, FARJAD B (Hydrology Dep, Shahid Chamran Univ of Ahvaz, Khuzestan, Iran, Email: atie hoseinizade@yahoo.com) : Potential impacts of climate change on groundwater resources: A multi-regional modelling assessment. J Earth Syst Sci 2019, 128(5), 131.

The complexity of understanding the groundwater resources in relation to climate change is caused by direct and indirect effects of climate change on hydrological processes. The study herein aims at implementing a physically based groundwater model to investigate the effects of climate change on groundwater system under 15 general circulation models (GCMs) in a semi-arid region from 2020 to 2044. A non-parametric probability density function estimator was used to quantify the level of uncertainties in the simulations. The method was applied to an area of 2073 km² in southwest Iran, consisting of five plains: western Dez, eastern Dez, Sabili, Deymche and Lor. The results indicate that there is a decline in the recharge in April, May, June and October. The range of changes in the recharge was determined to be between −10 % and +13 % in the Sabili plain, −6 % and +10 % in the Deymche plain, −4 % and +10 % in the western-Dez plain, −6 % and +26 % in the eastern-Dez plain, and −40 % and +100 % in the Lor plain. The most significant decline in the groundwater level occurred in the Sabili plain in September. The largest uncertainty in the simulation of recharge under GCM scenarios was determined to be in August, September and December. This study highlights that climate change can have a significant effect on groundwater resources in the region that reinforces the need for groundwater management plans and a long-term perspective.

15 illus, 2 tables, 65 ref

004035   KUMAR A, SRIDEVI C, DURAI V R, SINGH K K, MUKHOPADHYAY P, CHATTOPADHYAY N (India Meteorological Dep, Federal Government Office, New Delhi-110 003, Email: ashokscg@gmail.com) : MOS guidance using a neural network for the rainfall forecast over India. J Earth Syst Sci 2019, 128(5), 130.

In the present study, a model output statistics (MOS) guidance model was developed by using the neural network technique for a bias-corrected rainfall forecast. The model was developed over the Indian window (0–40 ^◦N and 60–100 ^◦E) by using the observed and global forecast system (GFS) T-1534 model output (up to 5 days) at a 0.125^◦ × 0.125^◦ regular grid during the summer monsoon (June–September) 2016. The skill of the developed MOS model forecast against the observed 0.125^◦ × 0.125^◦ grid rainfall data is obtained for the summer monsoon (June–September) 2017. The skill of the MOS model rainfall forecast is found to show good improvement over the T-1534 model’s direct forecast over the Indian window. In general, the T-1534 model’s direct forecast shows high skill but the forecast obtained by using the MOS model shows better skill than the direct model’s forecast, although a major improvement is seen for the Day 1 forecast at the national level. So the skill of the bias-corrected rainfall forecast by using the MOS guidance and the T-1534 model output is high and has the potential of being used as an operational forecast over the Indian region.

12 illus, 18 ref

004030   IMSONG W, CHOUDHURY S, PHUKAN S (Geology Dep, Nagaland Univ, Kohima- 797 001, Email: imsongnar@gmail.com) : Mid–late Holocene fluvial aggradational landforms and morphometric investigations in the southern front of the Shillong plateau, NE India. J Earth Syst Sci 2019, 128(5), 129.

The present study is an attempt to understand the antiquity of the preserved fluvial landforms and its response to the climate–tectonics nexus through geomorphological investigations along the Jadukata, Umpung, Umngot and Umtongoi rivers in the southern front of the Shillong plateau (SP), NE India. Sedimentological characteristics, chronological analyses and morphotectonic parameters were used to describe the spatial and temporal variability in the patterns of aggradation, landform evolution and neotectonic influences in the study. Our results indicate that valley aggradation processes occurred around the transitional zone in the southern front of the SP during the mid–late Holocene era along with a hiatus in sediment deposition after 4.3 ka. Sediment generation and aggradation is modulated by precipitation anomalies associated with the Indian Summer Monsoon (ISM) variability whereas morphometric analysis suggests that activity along the Dauki–Dapsi fault has been contributing to the uplift-related deformation. Sedimentological observation supported by optically stimulated luminescence chronology obtained on palaeoflood deposits, valley-fill fluvial terraces and alluvial fans indicate their deposition during three pluvial phases: (i) 5.3–4.3 ka, (ii) 2.4–1.0 ka and (ii) 0.7–0.3 ka. Our data indicate that valley aggradation and geomorphic processes in the southern part of SP responded to short-term changes in the ISM variability with contributions from the morphotectonic activities associated with the Dauki–Dapsi fault during the late Holocene period.

14 illus, 2 tables, 107 ref

004015   BURMAN P K D, SARMA D, MORRISON R, KARIPOT A K, CHAKRABORTY S (Indian Institute of Tropical Meteorology, Pune- 411 008, Email: pramit.cat@tropmet.res.in) : Seasonal variation of evapotranspiration and its effect on the surface energy budget closure at a tropical forest over North-east India. J Earth Syst Sci 2019, 128(5), 127.

This study uses 1 yr of eddy covariance (EC) flux observations to investigate seasonal variations in evapotranspiration (ET) and surface energy budget (SEB) closure at a tropical semi-deciduous forest located in north-east India. The annual cycle is divided into four seasons, namely, pre-monsoon, monsoon, post-monsoon and winter. The highest energy balance closure (76 %) is observed during pre-monsoon, whereas the lowest level of closure (62 %) is observed during winter. Intermediate closure of 68 % and 72 % is observed during the monsoon and post-monsoon seasons, respectively. Maximum latent heat flux during winter (150 W m⁻²) is half of the maximum latent heat (300 W m⁻²) flux during the monsoon. ET is a controlling factor of SEB closure, with the highest rates of closure corresponding to the periods of the highest ET. The Bowen ratio ranges from 0.93 in winter to 0.27 during the monsoon. This is the first time the role of ET in the seasonal variation of SEB closure has been reported for any ecosystem in north-east India using EC measurements.

11 illus, 3 tables, 107 ref

004042   MAURYA S P, SINGH N P, SINGH K H (Geophysics Dep, Banaras Hindu Univ, Varanasi- 221 005, Email: singhnpbhu@yahoo.co.in) : Use of genetic algorithm in reservoir characterisation from seismic data: A case study. J Earth Syst Sci 2019, 128(5), 126.

In the present paper, a seismic inversion based on genetic algorithm (GA) is performed to characterise the reservoir using seismic data only from the Blackfoot field, Alberta, Canada. The algorithm is first tested on synthetically generated data to optimise the GA parameters. The error analysis between the inverted and the expected results suggested that the performance of algorithm is exceptionally satisfactory. Thereafter, the inversion is performed for real seismic data from the Blackfoot field. The seismic data is first inverted for acoustic impedance section and then it is transformed into the velocity and density sections using the relation derived from the well-log data. The interpretation of the inverted/derived results depicts a low-amplitude anomaly zone between 1055 and 1065 ms time interval, which is characterised as a reservoir. The results demonstrate the efficacy and applicability of the GA in reservoir characterisation from the seismic data alone. This study is very helpful for the offshore projects where the information about well logs are missing.

16 illus, 2 tables, 38 ref

004021   DUTTA D, BISWAS T, MUKHERJEE S (Earth Sciences Dep, Indian Institute of Technology Bombay, Maharashtra- 400 076, Email: soumyajitm@gmail.com) : Arc-parallel compression in the NW Himalaya: Evidence from structural and palaeostress studies of brittle deformation from the clasts of the Upper Siwalik, Uttarakhand, India. J Earth Syst Sci 2019, 128(5), 0125.

The sub-Himalayan Upper Siwalik rocks, between the Main Boundary Thrust (MBT) to the north and the Main Frontal Thrust (MFT) to the south, are intensely brittle sheared and jointed. Our field studies around Dehradun (India) furnished at least eight small-scale brittle slip directions, viz., ∼top-to-SW/SSW (up), top-to-SW/SSW (down), top-to-NE/NNE (up), top-to-NE/ENE (down), topto-NW (down), top-to-SE/SSE (up), top-to-SE/SSE (down) and top-to-NW/NNW (up). Additionally, we report near-vertical faults, four sets of joints (inclined: J₁ and J₂; near-vertical: J_1V and J_2V). Palaeostress analyses using T-TECTO Studio X₅ with all joint sets reveal two compression directions ∼ENE–WSW and ∼NNW–SSE. We propose two possible temporal relations between the joint sets: (i) J₁, J₂, J_1V and J_2V are coeval (∼ENE–WSW compression) and (ii) J_1V and J_2V developed coevally (∼ENE–WSW compression) followed by J₁ and J₂ (∼NNW–SSE compression), because arc-parallel compression (if any) occurs later than arc-perpendicular compression. The presence of already well-known strike-slip faults, viz., the Yamuna tear fault and the Ganga tear fault, at high angles, ∼55^◦ and ∼85^◦ to the orogenic trend, implies a possible arc-parallel compression in the Siwalik Himalaya in the study area. This ∼NNW–SSE compression could also indicate a localised stress reorientation due to the curvature of the Thrust planes, viz., the MFT and the Asan Thrust (as observed in plan view) close to the study area. This study further shows that arc-parallel compression need not be restricted to the inner arc of an orogen, and/or, as in the case of the Himalaya, near the syntaxes.

14 illus, 1 table, 142 ref

004019   DORA M L, SINGH Y, JOSHI S, KUNDU A, SURESH G, RANDIVE K (Geological Survey of India, Nagpur- 440 006, Email: dorageol@gmail.com) : The first report on the chemical (Th–U–Pb) monazite age of the Mul granite pluton, Western Bastar craton, central India and its metallogenic significance. J Earth Syst Sci 2019, 128(5), 124.

Petrography and the geochemical attributes of the studied Mul granite pluton reveal mixed characteristics of A-type and I-type within-plate granites consistent with an extensional tectonic environment. The dominance of the primary biotite over the primary muscovite suggests its meta-aluminous nature. The dating of monazite from the Mul granitoid pluton by the in situ Th–U–Pb electron probe micro analyser chemical method indicates the tectonomagmatic event around 1602 ± 27 Ma in the western Bastar craton, Chandrapur district, Maharashtra. The age data possibly represent the emplacement of large bodies of grey granite and attendant monazite crystallisation at ∼1600 Ma. This monazite age implies that Mesoproterozoic magmatism is coeval with the formation of the Pranhita Godavari rift in the eastern flank in Maharashtra and associated with the copper and barite mineralisation in Thanewasna and the adjoining areas.

2 illus, 1 table, 30 ref

004022   ESSA K S, MUNSCHY M (Geophysics Dep, Cairo Univ, Giza, Egypt, Email: khalid_sa_essa@yahoo.com) : Gravity data interpretation using the particle swarm optimisation method with application to mineral exploration. J Earth Syst Sci 2019, 128(5), 123.

This paper describes a new method based on the particle swarm optimisation (PSO) technique for interpreting the second moving average (SMA) residual gravity anomalies. The SMA anomalies are deduced from the measured gravity data to eradicate the regional anomaly by utilising filters of consecutive window lengths (s-value). The buried structural parameters are the amplitude factor (A), depth (z), location (d) and shape (q) that are estimated from the PSO method. The discrepancy between the measured and the predictable gravity anomaly is estimated by the root mean square error. The PSO method is applied to two different theoretical and three real data sets from Cuba, Canada and India. The model parameters inferred from the method developed here are compared with the available geological and geophysical information.

12 illus, 8 tables, 55 ref

004059   SIVARAJAN N A, MISHRA A K, RAFIQ M, NAGRAJU V, CHANDRA S (Sathyabama Institute of Science and Technology, Chennai- 600 119, Email: daksha112@gmail.com) : Examining climate change impact on the variability of ground water level: A case study of Ahmednagar district, India. J Earth Syst Sci 2019, 128(5), 122.

This study focuses on examination of variability in the depth to water below ground level (bgl) from 1996 to 2016 in Ahmednagar district of Maharashtra, India in changing climate. Spatial variability of groundwater depth was mapped and classified as shallow, normal, deep and moderate using GIS modeling. Groundwater decline rates during successive decades were examined and critical areas with a significant fall in groundwater levels (GWL) were detected. Present study also focuses on examination of block-wise variability of GWL. Ground water level shows significant variability during 1996–2016 at confidence level 95 %. The long term ground water level fluctuation indicates that water levels in major parts of the study area have declined drastically. The depth to ground water in major parts of the study area ranges between 6 and 15 m bgl except in Parner and Shrirampur blocks. Furthermore, depth to water level is >15 mbgl over Sangamner block during the drought year 2004. Present study reports a significant decadal increase of about 0.7 m in water leval decline over the study area. Groundwater depletion over the study area has been observed with decrease in groundwater recharge and increase in temperature and urbanization. Groundwater depletion shows coherent variability with temperature. Our results report a significant decrease of about 0.61 cm/year in ground water recharge as a result of decrease in precipitation and a decadal increase of about 0.1 ^◦C in temperature over the study area. Evapotranspiration (ET) shows yearly increasing trend of about 9.6 mm over the study area. Results reported in this study highlight the importance of sustainable groundwater resource management over the study area.

7 illus, 2 tables, 19 ref

004038   KUMARI V R, SARMA V V S S, RAO G D, VISWANADHAM R, NAVITA B, SRINIVAS T N R, KRISHNA M S, REDDY N P C (CSIR-National Institute of Oceanography, Regional Centre, Visakhapatnam- 530 017, Email: rajaniwilliams@gmail.com) : Modifications in the trace gases flux by a very severe cyclonic storm, Hudhud, in the coastal Bay of Bengal. J Earth Syst Sci 2019, 128(5), 121.

A very severe cyclonic storm, Hudhud, made landfall at Visakhapatnam city, the central east coast of India, on 12 October 2014 and it is the most destructive cyclone to ever hit the Indian subcontinent since the past two decades. In order to examine its impact on the flux of trace gases into the atmosphere, a study was made in the coastal Bay of Bengal, off Visakhapatnam, after the cyclone and compared with the pre-cyclone conditions. Hudhud suppressed the vertical mixing of the water column due to the occurrence of strong salinity stratification associated with torrential rainfall. The land runoff and precipitation brought significant amount of ammonium to the coastal waters, resulting in increased pH. The increased pH shifted the inorganic carbon equilibrium towards the formation of bicarbonate, resulting in decreased partial pressure of carbon dioxide (pCO₂) after the cyclone Hudhud. The undersaturation of carbon dioxide (CO₂) and nitrous oxide (N₂O) with respect to atmospheric equilibrium was observed during the post-cyclone period compared to the pre-cyclone period. About 80 % of the post-cyclone decrease in N₂O (>2 nM) and pCO₂ (150–200 μatm) was contributed by the dilution of coastal waters with the precipitated waters. In contrast, methane (CH₄) concentrations were increased by 0.5–2.8 nM during the post-cyclone period than in the pre-cyclone period, and were attributed to the input of domestic sewage through land run-off. Dimethyl sulphide (DMS) and the total dimethyl sulphonio-propionate (DMSPt) concentrations decreased by 0.4–3.9 and 0.2– 6.0 nM, respectively, during the post-cyclone period in comparison with the pre-cyclone period and it was consistent with lower phytoplankton biomass during the former than the latter. The seato-air flux of CO₂, N₂O and DMS were 1.3 ± 0.5 mmol C m⁻²d⁻¹, 0.9 ± 0.3 μmol m⁻² d⁻¹ and 5.8 ± 3 μmol m⁻² d⁻¹ during the pre-cyclone period, respectively. The corresponding values during the post-cyclone period were lower at −2.0 ± 1 mmol C m⁻² d⁻¹, −0.4 ± 0.1μmol m⁻² d⁻¹ and 2.8 ± 2 μmol m⁻² d⁻¹, respectively. In contrast, the sea-to-air flux of CH₄ increased from 0.6 to 1.5 μmol C m⁻² d⁻¹ from the pre- to the post-cyclone period. This study suggested that the cyclone Hudhud modified the magnitude of the biogenic gas flux to the atmosphere from the coastal Bay of Bengal than hitherto hypothesised.

8 illus, 1 table, 68 ref

004014   BHATLA R, VERMA S, PANDEY R, TRIPATHI A (Geophysics Dep, Banaras Hindu Univ, Varanasi- 221 005, Email: rbhatla@bhu.ac.in) : Evolution of extreme rainfall events over Indo-Gangetic plain in changing climate during 1901–2010. J Earth Syst Sci 2019, 128(5), 120.

Due to climate variability and climate change there is an increase in magnitude and frequency of extreme precipitation events. During the last few decades these extreme rainfall events have been increased in global as well as on regional scale. Our climate is very much affected by the changes in frequency of extreme rainfall events. Particularly, variability of extreme rainfall events has been studied over one of the most valuable Indian region i.e. over Indo-Gangetic plain (IGP). Long term trend in extreme events has been analyzed with the help of IMD classification. The classification is considered for moderate rain (2.5– 64.4 mm; category I), heavy rain (64.5–124.4 mm; category II) and very heavy rain (124.5 mm or more; category III) and the categorization of rainfall events is based on daily rainfall for the period 1901–2010 during Indian summer monsoon (JJAS). The significant long term trend in frequency of extreme rainfall events is analyzed using the statistical test. Long term trend analysis shows the significant decreasing trend for categories II and III. However, an increasing rainfall frequency is observed for moderate rainfall events (category I) during the considered period. A significant interannual and inter-decadal fluctuation in rainfall frequency and magnitude were observed over IGP. Events of moderate and heavy rainfall increases during the withdrawal period of Indian summer monsoon, which might contribute in several cases of flood in the region of IGP. In term of distribution and contribution of rainfall in agriculture area categories I and II, rainfall events are more important but changes in rainfall pattern may lead to flood and drought risk over IGP. The policy making decision for disaster risk and food security should be based on spatial as well as temporal variability of rainfall pattern over IGP region.

5 illus, 3 tables, 39 ref

004053   SAHU L K, TRIPATHI N, SHEEL V, OJHA N (Physical Research Laboratory, Ahmedabad- 380 009, Email: lokesh@prl.res.in) : The influence of local meteorology and convection on carbon monoxide distribution over Chennai. J Earth Syst Sci 2019, 128(5), 119.

The influence of local meteorology and convection activities on the vertical distribution of carbon monoxide (CO) over Chennai in southern India was investigated by analysing the measurements of ozone aboard airbus in-service aircraft observations during the years 2012–2013. The seasonal variation of CO in the free troposphere was observed to be different and less pronounced than that in the planetary boundary layer (PBL). The near surface mixing ratio of CO was the highest (190 ± 68 ppbv) during winter, while enhanced values (117 ± 11 ppbv) in the free troposphere were observed during post-monsoon. The mixing ratios were the lowest throughout the troposphere during the monsoon. In the PBL, the mixing ratios of CO showed a decline with an increase in wind speed and were the highest (>200 ppbv) under stagnant conditions (1−2 m s⁻¹) during winter. The higher CO in the lower free troposphere during the pre-monsoon period is attributed to the stronger biomass burning emissions. In the middle– upper troposphere, higher levels of CO during post-monsoon are due to the enhanced vertical mixing of regional emissions associated with weaker wind shears and frequent convection activities. Overall, the contrasting effects of stronger CO emissions can be observed in winter/pre-monsoon, while the efficient vertical mixing during the monsoon/post-monsoon season governs the observed seasonality of CO. The model for ozone and related chemical tracers, version 4 (MOZART-4) provides a reasonable representation of the convection effect on the CO mixing ratio. This study highlights a need to conduct more observations, especially of aircraft-borne instruments, to understand the effects of regional-scale emissions and dynamics in the middle–upper tropospheric chemistry over South Asia.

6 illus, 1 table, 36 ref

004029   HRISHIKESH C G, NAGENDRA S M S (Civil Engineering Dep, Indian Institute of Technology Madras, Chennai- 600 036, Email: hcgautam.nitk@gmail.com) : Study of meteorological impact on air quality in a humid tropical urban area. J Earth Syst Sci 2019, 128(5), 118.

Urban air quality is highly dynamic and influenced by micrometeorological conditions. In this paper, meteorological impact on criteria air pollutants namely sulphur dioxide (SO₂), nitrogen dioxide (NO₂) and particulate matter (PM₁₀) were studied using correlation analysis at contrasting locations in the urban environment of Chennai city. Daily average air quality data from five monitoring stations during 2009–2012 were analysed. Out of the five monitoring locations, three locations (Kathivakkam, Thiruvottiyur and Manali) were categorised as industrial locations, General Hospital as a traffic intersection and Taramani as a residential location. The frequency distribution of industrial sites showed higher concentration compared to residential and traffic intersection sites (TS). The increase in annual average concentration of 15–38 %, 4–52 % and 5–58 % was observed for SO₂, NO₂ and PM₁₀ over the study period, respectively, attributed to vehicular and industrial emissions. SO₂ showed high correlation with humidity (R = −0.57) and cloud cover (R = 0.63) during summer. NO₂ showed a higher correlation with temperature (R = 0.72) during monsoon, and with humidity (R = 0.7) and cloud cover (R = 0.75) during winter. PM₁₀ showed moderate correlation with temperature (R = −0.55) and wind speed (R = −0.51) during summer. Non-parametric tests and Q–Q plot showed the distribution of SO₂ and NO₂ as Weibull and lognormal for PM₁₀. The wind rose plots depicted predominant wind direction in the south and south-west directions with most observations having a wind speed of ≥ 5 m/s. The estimated national ambient air quality index was good for traffic and residential sites. Industrial sites were moderately polluted during the winter season due to high PM₁₀ concentration. No exceedances were observed for daily concentration of SO₂ and NO₂. Daily average PM₁₀ concentration showed exceedances at industrial locations Kathivakkam, Manali and Thiruvottiyur for 305 (92 %), 84 (68 %) and 164 (53.4 %) days, respectively. At TS (General Hospital) and residential site (RS) (Taramani), lower number of exceedances was observed at 25 (13.2 %) days and 11 (5.8 %) days, respectively.

8 illus, 3 tables, 34 ref

004045   NATH B, NIU Z, MITRA A K (Beijing Normal Univ, Beijing- 100 101, Email: nath.gis79@gmail.com) : Observation of short-term variations in the clay minerals ratio after the 2015 Chile great earthquake (8.3M_w) using Landsat 8 OLI data. J Earth Syst Sci 2019, 128(5), 117.

In this paper, we explore the potential use of available free Landsat sensor data to investigate the shortterm variations (STV) in the clay mineral ratio (CMR) following the 2015 Chile great moment magnitude earthquake (8.3M_w). The present investigation was carried out in the absence of ground observation data. Landsat 8 Operational Land Imager (OLI)-based multi-temporal imageries of before, after and non-earthquakes were used to derive the above parameter by applying the band ratio approach of bands 6 and 7, where the before and after imageries were compared with non-seismic event images as well as for validation. For the temporal automatic lineament data extraction and final lineament mapping, band 8 (panchromatic) was used by applying the LINE algorithm technique of PCI Geomatica, and ArcGIS 10.5 software, respectively. All these derived products finally interact with the regional geology, fault line and lineament systems. The results reveal that CMR can easily identify the STV at temporal scales before and after the earthquake, while both are normal during non-earthquake time. However, this variation was observed in all three buffer zones (i.e., 50, 100 and 150 km buffer) and highly pronounced especially in the fault adjoining areas. Therefore, we found this research to be effective and could be used as an alternative method for future earthquake studies.

7 illus, 2 tables, 53 ref

004018   DAS S, CHAKRABORTY M (Geological Survey of India, Southern Region, Hyderabad, Email: sankhad56@gmail.com) : Petrology and geochemistry of mafic dyke and sills in Cumbum Formation, of the Proterozoic Nallamalai fold belt, Rajampet area, Andhra Pradesh, India. J Earth Syst Sci 2019, 128(5), 116.

Intensely deformed Proterozoic Nallamalai fold belt (NFB) occupies the eastern part of undeformed, Proterozoic Cuddapah basin and is separated from Cuddapah basin by easterly dipping Rudravaram thrust line. Igneous activity in NFB is represented by intrusive syenite and lamproite dykes. This study brings out the petrological and geochemical character of unreported intrusive dolerite dykes and sills within the Cumbum Formation of NFB. The dykes are undeformed, whereas the sills suffered D1 phase of deformation, although both are petrologically and geochemically similar. The rocks are highly fractionated sub-alkaline tholeiite, consist mainly of clino-pyroxene and plagioclase. Chondrite normalised rare earth element (REE) plot shows enriched light rare earth element (LREE) and flat heavy rare earth element (HREE). A primitive mantle-normalised multi-element spider diagram shows troughs in Nb, Ta, Ti and Zr indicating subduction zone character. Tectonic discrimination plots indicate both within-plate and subduction zone environment of formation. Geochemical modelling also indicates enriched spinel peridotite as a probable source for dykes and sills. We suggest that the lithospheric mantle beneath NFB got enriched by subduction-derived fluid around 1.6 Ga, and in later stage, these dykes and sills were generated by extension of the enriched lithosphere at different phases in turn inheriting the subduction zone geochemical characters.

8 illus, 6 tables, 53 ref

004065   VISSA N K, ANANDH P C, BEHERA M M, MISHRA S (Earth and Atmospheric Sciences Dep, National Institute of Technology Rourkela, Odisha- 769 008, Email: vissan@nitrkl.ac.in) : ENSO-induced groundwater changes in India derived from GRACE and GLDAS. J Earth Syst Sci 2019, 128(5), 115.

This study aims to quantify the interannual variations of groundwater storage changes (GWSCs) over India. GWSCs are derived from the gravity recovery and climate experiment (GRACE) and global land data assimilation system (GLDAS)-Noah life safety model (LSM) for the period 2003–2015. Estimated GWSCs are validated with the satellite altimetry over the six lake stations. The variability of GWSC and altimetry water-level heights are assessed with the cross-correlation and plotting analysis. Annual trends of GWSC and GRACE in terrestrial water storage (TWS) were estimated using the non-parametric Mann–Kendall test and Sen’s slope method. Results suggest that GWSC and TWS have declined in northern India at the rate of ∼1.6 cm yr⁻¹ and in southern and western central India at the rate of ∼0.5 cm yr⁻¹. Impacts of short-term climate perturbations such as El Ni˜no and La Ni˜na for the GWSCs are assessed. During the El Ni˜no period, the decline of GWSC over northern India enhanced, whereas during the La Ni˜na period, the recovery of GWSC is evident. These interannual variations of GWSCs over India are attributed by interannual precipitation changes. Under the global warming scenario, the occurrences of El Ni˜no events are likely to enhance in the future, and our findings help the water resource management policy makers for necessary actions during such short-term climate perturbations.

6 illus, 3 tables, 43 ref

004026   GIRI R K, PANKAJ P, PANDIT D, SAHOO S, CHAKRABARTI R, RAO N V C (Geology Dep, Banaras Hindu Univ, Varanasi- 221 005, Email: nvcrao@bhu.ac.in) : Pyroxenite dykes with petrological and geochemical affinities to the Alaskan-type ultramafics at the northwestern margin of the Cuddapah basin, Dharwar craton, southern India: Tectonomagmatic implications. J Earth Syst Sci 2019, 128(5), 114.

Two previously reported lamprophyre dykes from the Kalwakurthy area, at the northwestern margin of the Cuddapah basin, Dharwar craton, southern India, are reinvestigated. Petrography reveals that they have an overall cumulate texture and comprise clinopyroxene (dominant phase), amphibole (mostly secondary), magnetite, ilmenite and chromite and are reclassified as clinopyroxenites. The chemistry of clinopyroxene and chromite, bulk-rock major and trace element composition and the Sr–Nd isotopic systematics of the Kalwakurthy dykes strongly favour the involvement of subduction-related processes in their genesis and are strikingly similar to those of the continental arc-cumulates and Alaskantype ultramafics reported from the supra-subduction type of tectonic settings. Incompatible trace element ratios, involving high field strength elements, of these clinopyroxenites are also suggestive of the fluid-related metasomatism influencing their source regions. Petrogenetic modelling reveals that 10–20 % partial melting of the fertile lithospheric mantle source was involved in their genesis. The tectonomagmatic significance of the studied clinopyroxenites is evaluated in light of the existing models invoking a Neoarchaean subduction in the evolution of the Dharwar craton.

15 illus, 6 tables, 96 ref

004046   NG J L, AZIZ S A, HUANG Y F, MIRZAEI M, WAYAYOK A, ROWSHON M K (Civil Engineering Dep, UCSI Univ, Kuala Lumpur, Malaysia, Email: ngjl@ucsiuniversity.edu.my) : Uncertainty analysis of rainfall depth duration frequency curves using the bootstrap resampling technique. J Earth Syst Sci 2019, 128(5), 113.

Rainfall depth duration frequency (DDF) curves are used extensively in many engineering designs. However, due to the sampling error and the uncertainty associated with the parameter estimation process, the DDF curves are subjected to parameter uncertainty. In this study, an evaluation of the uncertainty of the DDF curves in the Kelantan river basin was performed using the bootstrap resampling method. Annual maximum rainfall series for durations of 24, 48, 72, 96 and 120 h were derived from the stochastic rainfall model outputs and fitted to the generalised extreme value (GEV) distribution. The bootstrap samples were generated by resampling with replacement from the annual maximum rainfall series. The relationships that describe the GEV parameters as a function of duration were used to establish the DDF curves. The 95 % confidence intervals were used as an indicator to quantify the uncertainty in the DDF curves. The bootstrap distribution of the rainfall depth quantiles was represented by a normal probability density function. The results showed that uncertainty increased with the return period and there was significant uncertainty in the DDF curves. The suggested procedure is expected to contribute to endeavours in obtaining reliable DDF curves, where the uncertainty features are assessed.

7 illus, 5 tables, 41 ref

004050   RATHOD S, DAHIWALKAR S, GORANTIWAR S, SHINDE M (Agricultural Research Station, Sangli- 416 305, Email: sdrathod2004@gmail.com) : Calibration of DRAINMOD for prediction of water table depths and drain discharges under waterlogged vertisols of Maharashtra, India. J Appl Nat Sci 2019, 11(3), 724-31.

An estimation of optimal design parameters of subsurface drainage system through moni-toring of water table depths and drain discharges are expensive in terms of time and money. The simulation modeling is an effective tool for estimation of drainage design parameters at less cost and short time. In view to this, calibration of DRAINMOD model for prediction of water table depths and drain discharges were conducted by installing subsurface drainage system with 40 m drain spacing and 1.0 m drain depth at Agricultural Research Station, Kasbe Digraj, Dist. Sangli (Maharashtra) during 2012-13 to 2013-14. The field data on water table depth and drain discharge were used for calibration of DRAINMOD model. The input data files on climatic, soil, crop and drainage design system parameters were attached to DRAINMOD model and calibrated successfully. It is found that both observed and simulated water table depths and drain discharges showed a fluctuating trend and predicted both water table depths and drain discharges closely with the observed values during frequent rainy days and following the rainy days. The DRAINMOD model reliably predicted water table depths with a goodness of fit (R² = 0.97), MAE (12.23 cm), RMSE (15.49 cm) and CRM (0.05); drain discharges with R² of 0.93, MAE of 0.095 mm day^-1, RMSE of 0.1876 mm day^-1 and CRM of 0.04. Thus, the calibrated DRAINMOD model can be used to simulate the water table depths and drain discharges in semi-arid climatic conditions of Maharashtra and in turn to estimate and evaluate drain spacing and depth.

4 illus, 6 tables, 31 ref

004013   AMITH G, NAVYASHREE S, PRAVEEN M, ARUL PRASAD S, SHABNUM P S (Agro Meteorology Dep, Agricultural Sciences Univ, Dharwad, Karnataka) : Assessment of occurrence and frequency of drought by percent normal precipitation index (PNPI) for Dharwad in northern transition zone of Karnataka. J Pharmacogn Phytochem 2019, 8(4), 324-5.

This study examined Percent Normal Precipitation Index (PNPI) for Dharwad in Northern Transition zone of Karnataka and the rainfall data was collected from 1951 to 2018 (68 years) for Dharwad. Drought is a prolonged period of abnormally low rainfall, leading to a shortage of water. Nowadays monitoring the drought is a crucial factor for risk management and providing impact assessments to overcome from such drought events. The Assessment of PNPI drought index was analyzed and result shows that Dharwad district have slightly decreasing trends in drought events and from 1951 to 2018 over 68 years it has shown that 9 years are in moderate drought, 19 years are in moderate wet and 40 years are in normal rainfall situation. This indicates effective real time contingency plans need to be formulated for increase in production of crops Dharwad in Northern Transition zone of Karnataka.

2 illus, 1 table, 3 ref

004064   VALLIAMMAI A (Tamil Nadu Agricultural Univ, Bhavanisagar, Tamil Nadu) : Assessment of climate change impact on watershed Hydrology. J Pharmacogn Phytochem 2019, 8(4), 263-8.

The hydrological parameters on water resources are of utmost importance for ensuring their appropriate management and utilization. The study was carried out to investigate the impact of climate change on watershed hydrology of Amaravathi river basin using SWAT model. The hydrological parameters viz., Precipitation, Soil moisture content, Surface Runoff, Evapo-Transpiration, and Groundwater Recharge was estimated spatially and temporally by water balance method using SWAT model. The Amaravathi river basin was divided into 15 sub basins based on the DEM and stream network. The monthly and annual hydrological parameters were simulated by SWAT for the period 1990 to 2017. The annual mean of soil moisture content was found to be 92.11 mm. The minimum and maximum soil water content was 65.00 mm and 110.73 mm occurred in 2013 and 1993. The maximum runoff of 703.24 mm occurred in the year 2013 and minimum runoff of 52.18 mm occurred in the year 1995. The average annual actual evapotranspiration varied between 477.81 mm (2008) to 303.78 mm (1995). The maximum and minimum groundwater recharge of 351.89 mm and 2.15 mm occurred in 2013 and 1995 with an average groundwater recharge of 105.43 mm. The decrease in recharge manifested itself as reduced discharge to streams and hence reduced stream flow. Hence the atmospheric moisture demand of the basin indicating the need of water from external / underground sources for successful crop production.

7 illus, 5 ref

004012   AATHEESWARI R, SURESH S, RAMANATHAN S P, JEBERLIN PRABINA B (Soil Science and Agricultural Chemistry Dep, Agricultural Coll and Research Institute, Tuticorin, Tamil Nadu) : Effect of different integrated nutrient management practices on soil fertility, rice productivity and profitability in Thamirabarani tract of Tamil Nadu. J Pharmacogn Phytochem 2019, 8(4), 217-20.

A field experiment was conducted in the Thamirabarani tract of Tamilnadu during pishanam season of 2018-2019 to study the effect of different INM practices on soil fertility, rice productivity and profitability in a sandy clay loam soil, Thamirabarani tract of Tamilnadu. The experiment was laid out in a randomized block design with 9 treatments and 3 replications. The results revealed that among the different INM practices STCR-IPNS along with application of biofertilizers on 15th& 30th days after transplanting recorded the highest productivity and profitability, followed by STCR-IPNS with basal application alone treatment. The same treatment recorded the highest yield (7.70 t ha^-1) as well as nutrient uptake besides profitability (Rs.386 ha^-1 day^-1) over the other treatments. The yield attributes were also improved by the same treatment. The STCR-IPNS treatment with biofertilizers (basal, 15th & 30th DAT) improved the soil available nitrogen, phosphorous, potassium and organic carbon after the harvest. The same treatment recorded the highest net return of Rs.42,436 ha^-1. Among the INM treatments 75 % RDF + GLM @ 6.25 t ha^-1 + biofertilizers- (basal 15th& 30th DAT) recorded the lowest net return of Rs.32,356 ha^-1.

4 tables, 8 ref

004039   LENINRAJA D, MUTHUMANICKAM D, BALAMURUGAN D (Tamil Nadu Agricultural Univ, Tuticorin, Tamil Nadu) : Delineation of soil available DTPA-manganese status in Tirunelveli district of Tamil Nadu using GIS techniques. J Pharmacogn Phytochem 2019, 8(4), 214-6.

A study was undertaken in Tirunelveli district of Tamil Nadu with a view to assess the micronutrient status of soils at block level. A sum of 1,798 geo-referenced surface soil samples from nineteen blocks of Tirunelveli district representing different soil units as per the soil map prepared on 1:50,000 scales were collected randomly at 0-15 cm depth using Global Positioning System. The soil samples were analysed for DTPA- Mn. The content of DTPA- Mn varied from 0.01 to 92.16 mg kg^-1 soil. Analytical results and the GPS data were used for the preparation of thematic maps showing spatial distribution of micronutrients status block wise in the district. Locations of soil sampling sites of Tirunelveli district were marked on base map on 1: 50,000 scales prepared from State Revenue Maps and digitized using Arc-info GIS. The delineation study thus clearly indicates that, the deficiency status of DTPA –Mn was low to the tune of 15.4 per cents.

2 illus, 1 table, 8 ref

004047   PATIL P B, JATKAR P R, ADSUL P B (Soil Science and Agricultural Chemistry Dep, Agriculture Coll, Latur, Maharashtra) : Physico-chemical properties in soils from Washi tahsil of Osmanabad district. J Pharmacogn Phytochem 2019, 8(4), 149-51.

A survey was conducted to know physico-chemical properties in soils from Washi Tehsil of Osmanabad district by GIS technique. For this purpose 180 soil samples were collected from 30 villages of Washi tahsil according to their representative depths during the year 2012-2013. Collected soil samples were categorized into different soil orders. From each village 2 soil samples of Vertisol (> 30 cm), Inceptisol (10-30 cm) and Entisol (0-10 cm) were collected. These soil samples were analysed for physico-chemical properties. In physical analysis, bulk density, particle density, porosity, soil colour were studied. Average bulk density, particle density, porosity 1.53 Mg m^-3 , 2.39 Mg m^-3 , 35.95 per cent, respectively. The soils under the study were neutral to alkaline in reaction, safe in electrical conductivity, low to moderate in organic carbon content and non-calcareous to calcareous in nature.

2 illus, 3 tables, 9 ref

002777   BAGDI G L (ICAR-Central Arid Zone Research Institute, Bikaner- 334004, Rajasthan, Email: glbagdi@yahoo.com) : Post-adoption behaviour of farmers towards soil and water conservation technologies of watershed management in semi-arid regions of Gujarat. Indian J Soil Conserv 2019, 47(1), 102-6.

ICAR-Indian Institute of Soil and Water Conservation (IISWC), Research Centre (RC), Vasad in Anand district of Gujarat has developed five model watershed projects in the past and implemented number of soil and water conservation (SWC) technologies for sustainable watershed management. Though many evaluation studies were conducted in the past but post-adoption status of the SWC technologies over a longer period had not been assessed. It was imperative to appraise the behaviour of the farmers with regard to the continuance or discontinuance of the technologies adopted, diffusion or infusion that took place and technological gaps that occurred in due course of time after completion of the project. Therefore, it was realized that the post-adoption behaviour of beneficiary farmers who adopted different SWC technologies during watershed management projects, should be studied in detail. The research study was initiated in 2012 as research project at ICAR-IISWC, RC, Vasad, district Anand, Gujarat, with the specific objective to measure the extent of post-adoption behaviour of farmers towards adopted SWC technologies of watershed management. In the study, various indices regarding continue adoption, discontinuance, technological gap, diffusion, infusion regarding SWC technologies for watershed management were developed. It was revealed that more than three-fourth (79.7 %) of SWC technologies were continued and one-fifth (20.3 %) were discontinued by the farmers. Out of the total continued adopted SWC technologies by farmers, one-third (33.7 %) of technologies were adopted with technological gap. About fifty percent (48.0 %) of SWC technologies were also diffused to other farmers' fields in nearby villages and on an average 1.3 number of technologies were also infused from outside by farmers' own efforts in the watersheds.

5 tables, 9 ref

002778   BANDYOPADHYAY S, GHOSH B N, DAS K, SAHOO A K, MUKHOPADHYAY S, HALDAR A, NAYAK D C, SINGH S K (ICAR-National Bureau of Soil Survey and Land Use Planning, Kolkata- 700091, West Bengal, Email: siladitya_555@yahoo.co.in) : Developing land use plan through advanced land resource inventory (LRI) technique in Chhotanagpur plateau region of Jharkhand. Indian J Soil Conserv 2019, 47(1), 63-73.

Land resource inventory (LRI) at 1:10,000 scale, using fine resolution remotely sensed data of IRS P6 LISS IV in Katkamdag block of Hazaribagh district, Jharkhand representing Chhotanagpur plateau region, India revealed 6 landforms, 11 soil series mapped in 13 soil mapping units (as phases of soil series) and 5 land management units (LMUs). Soil quality index (SQI) of LMUs revealed LMU 4 as the best land with percentage of goodness of SQI of 66.0, whereas, LMU 1 as poor land with the same as 27.9 %. Priority ranking of land management indicators (LMIs) divulged coarse texture of soils, low soil organic carbon (less than 0.50 %), low CEC [less than 5.0 cmol + -1 -1 (p⁺) kg^-1] and Zn deficiency (less than 0.6 mg kg^-1) as the major constraints for crop growth in LMU 1, 2 and 3. Impact assessment of LRI based land use plan (LUP) unveiled that LRI based alternate cropping systems with best management practices enhance the average annual net returns and average annual B:C ratio of the farmers by 207 % and 94 %, respectively over the existing cropping system.

6 illus, 7 tables, 35 ref