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The Himalayas, originated from the tectonic collision between India and the Tibetan plates, is a mountain range characterized by varying altitude, slope, aspect as well as the climate of the mountain resulting extensive ecological diversity. The Indian Himalayan region (IHR) covers 16.2% of the Total Geographical area (TGA) of India and spreads across 12 Indian states covering an area of 625,000–750,000 km2. Because of the varied climatic and physiographic features and heterogeneous nature of geological formations, there is a formation of various types of soils supporting variable forest flora and fauna. With the variation in altitude and climate, quite contrasting flora occurs at different altitudes. These lead to the formation of diverse type of forests from the foot hills to middle and upper hills and ultimately to alpine meadows above timber line. This sort of variation in forest type influences the development of different types of soils. In the Himalayas, different soil parameters (organic carbon, total N, fractions of humus carbon) bear significant positive correlation with altitude. However, soil pH and exchangeable bases show negative correlation with altitude. Studies conducted in the lower hills of the Himalayas indicate that teak (Tectona grandis) being a calcicolous plant increases the base saturation and organic matter content of soils over years and might help in developing organic-rich thick epipedon (surface horizon) in soils in near future to qualify many Inceptisols in this area into Mollisols (with organic matter-rich mollic epipedon). The northeastern part of the Himalayas is the convergence of different types of floras, including east Himalayan flora, Paleoarctic flora of the Tibetan highland and wet green flora of southeast Asia and Yunnan resulting tremendous biodiversity. In this region, there is a considerable variation of soil organic carbon (SOC) content in the surface layer. Of the total geographical area of northeastern region (15.61 million ha), variability of organic carbon content reveals that more than 1% SOC occupied by 98.54% area, more than 1.5% SOC by 57.68% area, more than 2.5% SOC by 13.44% area, and more than 3.5% SOC by about 1.0% area. The estimation of biomass carbon pool under T. grandis plantation in Darjeeling and Kurseong Himalayas indicates that aboveground biomass contributed major share (82%) toward the total biomass in comparison to that of the below-ground biomass (root biomass) (18%). The estimated total biomass carbon pool ranges from 57 to 136 tC ha−1, and the average carbon stock up to 90 cm soil depth was 189 tC ha−1. The higher SOC to biomass carbon ratio reflects the influence of altitude and climate especially precipitation toward the increasing SOC. The SOC stock measured up to the depth of 60 cm in upper and middle hill soils of Sikkim, and the Darjeeling Himalayas is more than double in comparison to that of lower hill soils suggesting the increase of SOC content with altitude. The same is true for the soils of temperate forest soils of Ladakh and Kashmir Himalayas. Soil organic carbon stock in Garhwal Himalayas is mostly influenced by its aspects. Northern aspects were reported to have more stable communities along with more fertile soils that eventually sequester more carbon stocks. SOC stocks in moist temperate forests soils in Himachal Pradesh are much higher in comparison to lower hill soils. Besides the soils of the IHR, the brown forest soils (Mollisols) of the Western Ghats and the Satpura range contain higher SOC (3%–4%) and are maintaining the SOC stock of 0.062 Pg mha−1 (per million hectares) (1 Pg, Petagram is 1015 g). Based on the estimation of the SOC stock under IHR and in other areas, it is evident that major part of the Himalayas maintained the minimum threshold value of SOC stock due to the congenial pedo-environment maniatined by the forst vegetations and, therefore, need to be protected. However, there are few areas which require more attention to improve the forest vegetation.

The performance of an extruded finned plate air heating solar collector is studied theoretically for paddy drying applications. Climatic conditions and solar radiation data are accounted based on Guwahati region (26.11˚N, 91.72˚E). Outlet air temperature and pressure drop are considered as controlling parameters to find optimum number of fins, fin height and fin thickness. Outlet air temperature increases and then decreases with number of fins whereas pressure drop increases with number of fins. The analysis showed that finned plate air heating solar collector with 80 fins, 0.6 Height (H) to-Duct length (D) ratio and 2 mm fin thickness yield best results for paddy drying applications at Guwahati weather conditions.

The mineralogical compositions along with physical, chemical, elemental and mineralogical properties of four pedons occurring along a toposequence in Chhota Urla village (Abhanpur tehsil), Raipur district of Chhattisgarh state were studied. Landform had significant influence on physical, chemical, elemental and mineralogical properties of soils. Sand content decreased from higher topography to lower topography but clay content increased with decrease in elevation. pH of pedons ranged from strongly acid to moderately alkaline and CEC increased from upland to lowland. Quartz being dominant in sand fraction and absence of primary minerals like Ca-feldspar, K-feldspar indicated intense weathering of soils. Silt had quartz as dominant mineral followed by Ca- feldspar and K-feldspar. Kaolin was dominant mineral in clay fractions of pedons l and 2 (PI and P2) with sub-ordinate amount of smectite while smectite was dominant in other two pedons followed by kaolin. Huge amount of smectite which is first weathering product of plagioclase, did not find its parental legacy with underlying geology (sandstone, limestone and shale sequence) indicative of mixed alluvium, eroded from different geological formation and contradicted the occurrence of catenary sequence as reported earlier.

Vertisols have the capacity to shrink and swell, inducing cracks and distinctive soil structure throughout the soil profile. In India they occur in various agro-ecological regions such as humid tropical (HT), sub-humid moist (SHM), sub-humid dry (SHD), semi-arid moist (SAM), semi-arid dry (SAD) and arid dry (AD) climatic environments and thus indicate an array of soils in a climosequence. In this study benchmark Vertisols, series Panjari is from sub-humid (dry), Kheriis from sub-humid (moist) region, Teligi and Akola series are from semi-arid (dry) and Nimone is from arid agro-ecological region. All the Vertisols in general are characterized by dark colour, angular to sub-angular blocky structure and clay in texture and calcareous. These soils have high bulk density and high water retention capacity. These soils have deep, wide-opened desiccation cracks at the surface which extend deep into the profiles and the depth of cracks increases with aridity. Soils of all climates are dominated by Ca2+ ion in their exchange complex throughout the depth. However, in the sub-humid climate Mg2+ ions tends to dominate in the lower horizon. Whereas the semi-arid dry (Akola) soils have high Na+ ions in their exchange complex. The soils are slightly alkaline to strongly alkaline in nature and poor in organic matter. The CEC varied from 59.3 to 68.2cmol (p+) kg-1 in soil of Panjari series which is highest followed by Teligi series profile. The calcium carbonate (CaCO3) shows gradual increase with depth in all the soil profiles, though it is preferentially accumulated in the sub-surface horizons of lower rainfall region soils.In climosequence the soils of the sub-humid region are generally Typic Haplusterts, soils of semi-arid region are Typic/Sodic/Calcic Haplusterts and soils of arid region are Sodic/ Calcic/ Aridic Haplusterts. The present study demonstrates how the soil properties of Vertisols in a different climate may help in inferring the change in climate in a geologic period.

The importance of soil-physiographic relationship in soil survey and mapping provide a fair understanding of variability across the landscape needed for sustainable agricultural planning. Keeping this in view the swell- shrink soils of the Ramagarh village of Purna valley in Amravati district, Maharashtra in semi-arid region of central India were studied for their morphological, physical and chemical characteristics and soils were mapped at 1: 8000 scale in geographical information system (GIS) platform. The soils of Ramagarh village are very deep, dark grayish brown to very dark grayish brown in colour, clayey in texture and exhibits medium, moderate, sub angular blocky structure in the surface layers and the subsoil horizons have medium, weak to strong angular blocky structure. Soils are alkaline in reaction, calcareous in nature and low to medium organic carbon content. The pH, CaCO3 and exchangeable sodium percentage (ESP) increase with depth in all the soils. Because of high smectitic clay content and ESP down the profile, these soils have impeded drainage and show ponding of water in the rainy season. The soils of the uplands are classified as Sodic Haplusterts and low land soils belong to Typic Haplusterts category at sub group level. The study indicates that the soils are sodic chemically degraded in 18.2% area of the TGA of the village. The higher ESP was related to corresponding decrease in exchangeable calcium and increase in exchangeable magnesium.

Flood is a natural or manmade phenomenon and timely and accurate forecasting of flood is very important. However forecasting of flood is a difficult task due to influence of rainfall-runoff process which depends on various factors. Estimation of surface runoff in a watershed is based on the rate of precipitation and discharge at the outlet. In this study, runoff from micro watersheds of Urmodi basin in Maharashtra state was computed by Soil Conservation Service-Curve Number method using remote sensing and Geographic Information System (GIS) techniques. Various thematic maps such as soil map, land use/land cover, stream order, slope etc. were prepared using remote sensing and GIS. Daily rainfall data was used for determining runoff. Antecedent moisture conditions were determined from daily rainfall data and for different CNs with the help of combined land use land cover and hydrologic soil group map in GIS environment. Results showed that the highest runoff for Bharatgaon and Nagthane micro watersheds was 46.20 mm and 54 mm respectively. Total runoff depth for the year 2014 was computed as 215.05 mm for Bharatgaon micro watershed and 277.68 mm for Nagthane micro watershed. Different soil and water conservation measures and water harvesting structures were recommended to control soil erosion and to harness the surface runoff.

The depletion of the ozone layer due to the greenhouse effect has created great concern that led to several studies on qualities, kinds, distribution and behavior of soil organic carbon (SOC). The first ever comprehensive study of OC status in Indian soils was conducted by Jenny and Raychaudhuri. Difference in sampling methods, exact season of collecting soil samples on different types of landscapes and kinds of vegetation and the methods of soil analyses in the laboratory determine the quality of SOC data. An attempt has been made to estimate the SOC stock in different soil orders as per Soil Taxonomy. The SOC stock for India in terms of each soil order is estimated at 0–30 and 0–150 cm depths since quantitative data reflect the kinds of soil with different amount of OC at different depths. The accumulation of OC in Indian soils, however, is dependent on the rate of decomposition of OC due to higher temperature in the tropics.

Agro-Ecological Sub-Regions (AESRs) of the country were conceptualized using limited soil data and accordingly a map

Maintenance of soil organic carbon (SOC) stock is important for monitoring soil health, which appears to be fragile in view of the reported climatic changes due to global warming in tropical countries such as India. This requires accurate and reproducible measurement of SOC. The wet-digestion technique following the Walkley-Black (WB) method to determine SOC has been used throughout the world in soil science, agronomy, and environmental science laboratories. WB suggested a universal correction factor to convert organic carbon to calculate exact quantity of organic carbon present in soil assuming 77% recovery of SOC. We understand that such a blanket recommendation may not hold well in different bioclimatic systems and for soils representing various depths. We present corrected Walkley-Black recovery factors (WBRFc) for different bioclimates and soil depths in two food-growing zones in India.

There have been numerous efforts worldwide at various scales (global/national/regional/ local) in the field of development of sustainable development indicators, focussing on either one or all of its various dimensions, following the Rio Summit in 1992. However, India has fallen behind in the area of development of Sustainable Development Indicators and none of the Indian cities figure in the review of the IISD Compendium, the most comprehensive database to date to keep track of Indicators efforts. A review of the initiatives by several international agencies and countries in formulation of the sustainability indicators though provide necessary guidance, the final framework needs to address the urban sustainability issues in the Indian context. The objective of this paper is to develop a set of indicators at macro and micro level for environmentally sustainable development of the urban settlements in India. It involves recommending an approach, a methodology and a structural framework for deriving the indicators set at various levels focussing on resource dynamics of urban settlements. Domain based classification has been followed wherein domains have been identified based on essential natural and built in resources. Further, for each domain environmental sustainability determinants have been recognised and based on them multilevel indicators have been identified with a goal of greater livibility and quality of life. A way forward has been given for the evaluation of indicators for formulation of policies at national level and action plan at local level with stakeholder’s participation. key words: Environmental Sustainability, Urban Settlements, Frameworks, Indicators, Macro level, Micro level.

A study was undertaken in the established benchmark (BM) soil series in different agro-ecological sub-regions of Indo-Gangetic Plains (IGPs), India with an objective to assess the urease activity and its kinetics at different soil depths. The urease activity declined with increase in soil depth in all the selected BM soils of IGP. The mean urea hydrolysis in the surface horizon (0–30 cm; 18.2 µg $$ {\text{NH}}_{4}^{ + } $$ /h) was 2.6-folds higher than the sub-surface horizon (121–150 cm; 7.01 µg $$ {\text{NH}}_{4}^{ + } $$ /h). The enzyme velocity (V max ) and enzyme efficiency (K m /V max ) of urease hydrolysis were at par in surface and sub-surface horizons. The average K m value of urease enzyme in surface and sub-surface horizons were 4.53 and 3.96 mM, respectively. The coefficient of variation, K m for surface horizons showed higher variability and low affinity of soil urease towards substrate urea than the sub-surface horizon. Negative Pearson’s correlation coefficient was recorded between urease activity and soil depth (R = −0.86), while significant positive correlation was observed between urease activity with organic carbon (R = 0.81) and nitrogen (R = 0.81).

The outcomes of the discussion in the four working sessions showed that although there is an urgent need to improve soil carbon management and stocks, and despite the existing knowledge about good agricultural practices to achieve this goal, these are not put into practice effectively and globally. The apparent contradiction has to do with a mismatch of policies at different societal and geographical scales, and the low policy profile of SOC. All participants agreed in the need to bring SOC into the core of environmental policies at all levels and to improve the governance of policy actions by addressing the stakeholders in a more effective way. Fil: Banwart, Steven. University of Sheffield. Kroto Research Institute; Reino Unido Fil: Black, Helaina. James Hutton Institute; Reino Unido Fil: Cai, Zucong. Nanjing Normal University; China Fil: Gicheru, Patrick. Kenya Agricultural Research Institute; Kenia Fil: Joosten, Hans. University Greifswald; Alemania Fil: Victoria, Reynaldo. Universidade de Sao Paulo; Brasil Fil: Milne, Eleanor. State University Of Colorado Boulder; Estados Unidos Fil: Noellemeyer, Elke Johanna. Universidad Nacional de La Pampa. Facultad de Agronomía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Pascual, Unai. Basque Centre for Climate Change; España Fil: Nziguheba, Generose. Columbia University; Estados Unidos Fil: Vargas, Rodrigo. University of Delaware; Estados Unidos Fil: Bationo, Andre. International Fertilizer Development Center; Ghana Fil: Buschiazzo, Daniel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentina Fil: de Brogniez, Delphine. European Commission; Italia Fil: Melillo, Jerry. Ecosystems Centre of The Marine Biological Laboratory; Estados Unidos Fil: Richter, Dan. University of Duke; Estados Unidos Fil: Termansen, Mette. University Aarhus; Dinamarca Fil: van Noordwijk, Meine. International Centre for Research in Agroforestry; Indonesia Fil: Goverse, Tessa. United Nations Environment Programme. Division of Early Warning and Assessment; Kenia Fil: Ballabio, Cristiano. European Commission; Italia Fil: Bhattacharyya, Tapan. Indian Council of Agricultural Research. National Bureau of Soil Survey and Land Use Planning. Division of Soil Resource Studies; India Fil: Goldhaber, Marty. United States Geological Survey; Estados Unidos Fil: Nikolaidis, Nikolaos. Technical University of Crete; Grecia Fil: Zhao, Yongcun. Chinese Academy of Sciences; República de China Fil: Funk, Roger. Leibniz Centre for Agricultural Landscape Research. Institute for Soil Landscape Research; Alemania Fil: Duffy, Chris. State University of Pennsylvania; Estados Unidos Fil: Pan, Genxing. Nanjing Agricultural University; China Fil: la Scala, Newton. Universidade Estadual Paulista Julio de Mesquita Filho; Brasil Fil: Gottschalk, Pia. Potsdam Institute for Climate Impact Research; Alemania Fil: Batjes, Niels. International Soil Reference and Information Centre. World Soil Information; Bélgica Fil: Six, Johan. Eidgenössische Technische Hochschule Zürich; Suiza Fil: van Wesemael, Bas. Université Catholique de Louvain; Bélgica Fil: Stocking, Michael. University of East Anglia; Reino Unido Fil: Bampa, Francesca. Università di Padova; Italia Fil: Bernoux, Martial. French Research Institute for Development; Francia Fil: Feller, Christian. French Research Institute for Development; Francia Fil: Lemanceau, Philippe. Institut National de la Recherche Agronomique; Francia. University of Burgundy; Francia Fil: Montanarella, Luca. European Commission; Italia

The present study was undertaken with an objective to study the impact of pedo-edaphic environments, cropping systems, land use, and management practices on the MBC. Soil samples were collected from seventeen benchmark soils representing different agro-ecological sub regions of black soil region of India. The pooled comparisons of MBC in different bio-climates indicated significant differences (p

Information on soil hydraulic properties is a prerequisite in irrigation management decisions and crop planning. Such information on soils of the black soil region (BSR) occupying 7.7×107 ha of India is sparse. Soil profile information for 49 representative sites (244 samples) was collected and used for analysis. Ten different functions were evaluated for their efficacy to describe soil water retention characteristics (SWRC) of the BSR soils. Campbell model fitted to measured SWRC data with relatively lower root mean square error (RMSE=0.0214 m3·m−3), higher degree of agreement d=0.9653), and lower absolute error on average (MAE=0.0165 m3·m−3). The next best description was by van Genuchten (VG) function with RMSE (0.0249 m3·m−3), d(0.9489), and MAE (0.0868 m3·m−3). Pedotransfer functions (PTF) were developed to predict field capacity (FC) and permanent wilting point (PWP) using nearest neighbor (kNN) algorithm and artificial neural networks (ANN). Four levels of input information used for po...

A study was undertaken in the established benchmark soil series in different agro-ecological sub-regions of Black Soil Regions of India with the objective to assess the urease activity as a function of soil depth, bio-climate, cropping system and land use type. The urease activity declined with increase in soil depth. Maximum activity was restricted within 0–30 cm of soil depth. Cropping systems and bio-climates significantly (p sub-humid (dry) > semi-arid (dry) > arid. The activity in different cropping systems was in decreasing order viz. legume- > sugarcane- > cereals- > cotton-based cropping system. Higher urease activity was observed in irrigated agro-systems as compared to the rainfed agricultural systems. High management practices increased urease activity as compared to low management. In physical properties, urease activity was negatively correlated with sand, fine clay, bulk density and available water content. Electrical conductivity, calcium carbonate and cation exchange capacity showed negative correlation in chemical properties at all the soil depths.

This study documents the coupling of provenance and climate change over the last 100 ka manifested in clay mineralogy of sediments from two cores (~ 50 m deep) in the Ganga–Yamuna interfluve in the Himalayan Foreland Basin, India. Depth distribution of the texture and clay mineral assemblage in the two cores show notable differences on account of pedogenesis and sediment supply over the last 100 ka. Core sediments from the northern part of the interfluve (IITK core) are micaceous and dominated by hydroxyl-interlayered dioctahedral low-charge smectitea (LCS) in fine clay fraction but by trioctahedral high-charge smectite (HCS) in silt and coarse clay fractions. In contrast, core sediments from the southern part of the interfluve (Bhognipur core) are poor in mica and both LCS and HCS are recorded in the upper 28 m of the core while the lower part is dominantly LCS in all size fractions. The paleosols in the two cores formed in the sub-humid to semi-arid climatic conditions resulting in clay minerals such as 1.0–1.4 nm minerals, vermiculite, HCS and also preserved the LCS, hydroxyl-interlayered vermiculite (HIV) and pseudo-chlorite (PCh), and kaolin that formed earlier in a humid climate. The preservation of LCS, HIV, kaolin and PCh is a clear indicator of climate shift from humid to semi-arid in the Ganga Plains as their formation does not represent contemporary pedogenesis in the alkaline chemical environment induced by the semi-arid climate. As the simultaneous formation of both HCS and LCS is not possible at the expense of mica, the abundance of LCS sediments from both the cores suggests the role of plagioclase weathering in the formation of LCS. In the upper 28 m of the Bhognipur core, the presence of both HCS and LCS in the fine clays suggests a change in sediment provenance from cratonic to a dominantly Himalayan source during Holocene. The climatic records inferred from the typical clay mineral assemblages of the two interfluve cores are consistent with the Marine Isotope Stages (MIS). The humid interglacial stages (MIS 5, 3, and 1) are marked by dominance of HIV, PCh, and LCS whereas the dominance of HCS together with pedogenic carbonate (PC) is noted in semi-arid stages (MIS 4 and 2).

Agro-Ecological Sub-Regions (AESRs) of the country were conceptualized using limited soil data and accordingly a map was generated way back in 1994. The present paper revisits the AESR concept to revise this map with the help of georeferenced soil information system (GeoSIS) recently developed at the sub-country levels of the Black Soil Region (BSR) and the Indo-Gangetic Plains (IGP). GeoSIS has been proved to be an excellent tool in successful application of Agro- Ecological Sub Regions (AESRs) at the regional and national levels. This novel approach could narrow the knowledge gap in revising the soil and agro-management technologies, used in dry land agriculture for productivity enhancement with special reference to the BSR dominated by cotton and soybean cropping systems. For the IGP, similar approach was used for the rice-wheat cropping systems. Revised AESR map identifies the areas under different level of productivity of these four important crops of two major food-growing regions of the country. The identified areas in the form of thematic maps shall help the planners and land resource managers to prioritize areas for resource management.

Carbon content in soils changes depending on the land use system, type of management practice and time. There is an increasing concern about the soil quality vis-a-vis organic carbon content in soils due to global warming and enhanced CO 2 concentration in the atmosphere. This has led to estimate carbon stock in soils at global and regional levels. The objective of the present study was to evaluate Roth C model to estimate total organic carbon (TOC) changes under four long term fertilizer experimental sites representing sub-humid moist (Sarol and Nabibagh), sub-humid dry (Panjri) and semi-arid (Teligi) climate in India. The plant carbon input rate was calibrated using organic carbon and other soil parameters using Roth C . The results showed that Roth C could simulate changes in TOC in two contrasting eco-sites for surface soil layers. The root mean square error (RMSE) considered as modelling error ranged from 11.50 to 15.01, 4.70 to 11.60, 2.14 to 6.52 and 1.45 to 13.74 in the surface layers of Sarol, Nabibagh, Panjri, and Teligi sites, respectively. The simulation biases expressed by M (relative error) by Student‘ t ’ value for all the treatments at these sites were non-significant with two exceptions. Observed trends in TOC consist of an increase for all the four treatments in the sub-humid site of Sarol and Nabibagh; while manures alone or in combination increase TOC appreciably in Teligi and Panjri. TOC remained, however, almost similar over years for the control (no fertilizer or manure) and NPK treatments in all the four sites. Analysis of Roth C output data showed that this model could be used as a tool to arrive at different threshold values of rainfall to influence decomposition rate modifier and thus to find out rate of organic carbon sequestration in various bioclimatic systems.

Background: Clear cell renal cell carcinoma (CCRCC) is the commonest form of kidney cancer. Up to 91% have biallelic inactivation of VHL, resulting in stabilisation of HIF-α subunits. Factor inhibiting HIF-1 is an enzyme that hydroxylates HIF-α subunits and prevents recruitment of the co-activator CBP/P300. An important question is whether FIH-1 controls HIF activity in CCRCC. Methods: Human VHL defective CCRCC lines RCC10, RCC4 and 786–O were used to determine the role of FIH-1 in modulating HIF activity, using small interfering RNA knockdown, retroviral gene expression, quantitative RT–PCR, western blot analysis, Annexin V and propidium iodide labelling. Results: Although it was previously suggested that FIH-1 is suppressed in CCRCC, we found that FIH-1 mRNA and protein are actually present at similar levels in CCRCC and normal kidney. The FIH-1 inhibition or knockdown in the VHL defective CCRCC lines RCC10 and RCC4 (which express both HIF-1α and HIF-2α) resulted in increased expression of HIF target genes. In the 786-O CCRCC cell line, which expresses only HIF-2α, FIH-1 attenuation showed no significant effect on expression of these genes; introduction of HIF-1α resulted in sensitivity of HIF targets to FIH-1 knockdown. In RCC4 and RCC10, knockdown of FIH-1 increased apoptosis. Suppressing HIF-1α expression in RCC10 prevented FIH-1 knockdown from increasing apoptosis. Conclusion: Our results support a unifying model in which HIF-1α has a tumour suppressor action in CCRCC, held in check by FIH-1. Inhibiting FIH-1 in CCRCC could be used to bias the HIF response towards HIF-1α and decrease tumour cell viability.

This study reports the micromorphological record of a continuous set of samples from paleosol-bearing intervals of two subsurface cores of ∼50 m depth representing typical pedosedimentary sequences of the Ganga–Yamuna interfluve in the western Ganga Plains. Micromorphology (microstructures, rhizocretes, Fe–Mn features, pedogenic carbonate, illuvial clay coatings and relict pedofeatures) was used to characterize pedogenic processes in the 13 paleosols in the IITK core and the 10 paleosols in the Bhognipur core. Formation of these paleosols took place through incipient to moderate weathering on relatively stable surfaces of the Ganga–Yamuna interfluve over the last 100 ka. These paleosols range in character from simple ones having weakly developed pedofeatures to mature paleosols with strongly developed pedofeatures and are similar to modern Entisols, Inceptisols, Alfisols and Vertisols of the Ganga Plains. Pedosedimentary evolution in the two interfluve successions differs in terms of stratigraphic stacking of paleosols, types of paleosols, and heterogeneous nature of sediments. In the northern part, the IITK interfluve core is marked by a thick mature paleosol with a strongly developed argillic (Bt) horizon at 41–45 m depth and weakly developed paleosols in the remaining part of the core. The mature paleosol represents a major discontinuity when prolonged pedogenic activity took place on stable surfaces with little or no deposition. On the other hand, thin-simple–thick cumulic paleosols with weakly developed pedogenic features, even with some preservation of sedimentary laminations indicate short stratigraphic breaks in rapidly aggrading sediments. In the southern part, the Bhognipur core is marked by the heterogeneous nature of sediments with a predominance of cratonic sediments in the lower part and the Himalayan sediments in the upper parts. In contrast, the IITK core shows a Himalayan source throughout. The entire interfluve succession in the Bhognipur region is marked by rapid sedimentation and short pedogenic intervals of weakly developed paleosols excepting one mature paleosol with well-developed argillic (Bt) and vertic (Bss) horizons at 10–14 m depth. This mature paleosol possibly formed synchronously with a mature paleosol from the northern part of this interfluve. The mature paleosol in both the cores represents a major stratigraphic break of 8000–10,000 years when prolonged pedogenesis occurred over large areas of the Ganga–Yamuna interfluve following regional degradation and local gullying in response to climate change from sub-humid to semi-arid conditions during the MIS 5–4 transition.

Two long-term fertilizer experiments (LTFE) datasets were used to evaluate the performance of the Century ecosystem model in contrasting regions of India viz Mohanpur (humid) and Akola (semi-arid) with mean annual rainfall of 1619 mm and 793 mm, respectively. Mohanpur grew rice and wheat in rotation for 19 years since 1986. Akola grew sorghum and wheat in rotation for 9 years since 1988. Both these experiments involved treatments with different doses of inorganic (fertilizer) and organic (farm yard manure, paddy straw, and green manure) inputs. The model closely resembled measured SOC level for all the treatments in Mohanpur LTFE. For Akola, it tended to overestimate treatment effects at the end of the experimental period. At the humid site (Mohanpur) modelled data simulated measured data reasonably well for all treatments, with control and treatments with fertilizer alone and in combination with organic inputs showing the best agreement (RMSE 1–3). At the semi-arid site Century performed well for the early years, but lower during the end of the experiment. The comparison between measured and modelled yields for the three crops (rice, wheat and sorghum) showed a reasonably good correlation ( r = 0.8).

There are many reports on soil parameters that have both yield-reducing and yield-favouring potential. However, only a few are available on the index soil properties of fibrous minerals containing soils on crop yields in the semi-arid tropical (SAT) regions. These minerals in soils are mostly palygorskite and sepiolite. In the present study, only the palygorskite mineral in black soils (cracking clay soils), its formation and probable influence on soil quality is addressed. The present study was also undertaken to indicate a possible genesis of palygorskite in Indian black soils with and without soil modifiers (Ca-zeolites and gypsum) supporting both rainfed and irrigated agriculture in SAT environments. Palygorskite is absent in aridic/ gypsic/sodic intergrades of black soils (Haplusterts), which might indicate non-interference of soil modifiers in its formation. Palygorskite is present only in sodic black soils (Calciusterts) in Maharashtra and parts of central and western India that contain no soil modifiers, and are under both rainfed and irrigated agricultural systems. The severe impairment of hydraulic properties of palygorskite containing naturally degraded black soils warrants a new research initiative for soils containing fibrous minerals.

Smectitic parent material from the weathering Deccan basalt has been deposited in the lower piedmont plains, valleys and microdepressions during a previous wetter climate. The cracking clay soils (Vertisols) were developed in such alluvium during drier climate of the Holocene period. In India they occur in humid tropical (HT), sub-humid moist (SHM), sub-humid dry (SHD), semi-arid moist (SAM), semi-arid dry (SAD) and arid dry (AD) climatic environments and thus indicate an array of soils in a climosequence. The soils show a change in their morphological, physical, chemical and micromorphological properties in the climosequence. Soils of HT climate are dominated by Ca++ ions in their exchange complex throughout depth. However, in the sub-humid climates Mg++ ions tend to dominate in the lower horizons. The sub-humid moist to aridic climatic environments caused a progressive formation of pedogenic calcium carbonates (PC) with the concomitant increase in Na+ ions in soil solution. This facilitated the translocation of Na-clay in the soil profile. This is responsible for the increase in pH, decrease in Ca/Mg ratio of exchange sites with depth and finally in the development of subsoil sodicity. The reduction in mean annual rainfall (MAR) from sub-humid moist to arid climates accelerated the formation of PC and thus the soils of semi-arid and arid climates (SAM, SAD and AD) are more calcareous and sodic than soils of other climates (SHM and SHD). Formation of PC, illuviation of clay and the development of subsoil sodicity are concurrent, contemporary and active pedogenetic processes operating during the climate change of the Holocene period. These processes impaired the hydraulic properties of soils in general, and in soils of drier climates in particular. As a result, cracking pattern, chemical composition and plasmic fabric were more modified in soils of the drier climates. Such modifications in soil properties have a place in the rationale of Vertisol order of the US Soil Taxonomy. The soils of wetter climates (HT, SHM and SHD) are grouped in Typic Haplusterts whereas the soils of drier climates (SAM, SAD and AD) are classified as Aridic Haplusterts, Sodic Haplusterts and Sodic Calciusterts. The present study demonstrates how the intrinsic soil properties of the cracking clay soils in a climosequence may help in inferring the change in climate in a geologic period.

This paper reviews the research conducted by ICRISAT and its partners on the role of management systems on carbon sequestration and crop productivity in the semi‐arid regions of India. It is now established that apart from water shortages, the dryland productivity is also constrained by low fertility mainly caused by the low organic matter status of most soils. Sequestration of atmospheric carbon dioxide in the soil has the potential to achieve the multiple objectives of improving the soil quality and fertility of the semi‐arid tropical soils, increasing crop productivity, improving livelihoods and maintaining environmental quality.

National and sub-national scale estimates of soil organic carbon (SOC) stocks and changes can provide information land degradation risk, C sequestration possibilities and the potential sustainability of proposed land management plans. Under a GEF co-financed project, ‘The GEFSOC Modelling System’ was used to determine SOC stocks and projected stock change rates for four case study areas; The Brazilian Amazon, The Indo-Gangetic Plains of India, Kenya and Jordan. Each case study represented soil and vegetation types, climates and land management systems that are under represented globally, in terms of an understanding of land use and land management systems and the effects these systems have on SOC stocks. The stocks and stock change rates produced were based on detailed geo-referenced datasets of soils, climate, land use and management information. These datasets are unique as they bring together national and regional scale data on the main variables determining SOC, for four contrasting non-temperate eco-regions. They are also unique, as they include information on land management practices used in subsistence agriculture in tropical and arid areas. Implications of a greater understanding of SOC stocks and stock change rates in non-temperate areas are considered. Relevance to national land use plans are explored for each of the four case studies, in terms of sustainability, land degradation and greenhouse gas mitigation potential. Ways in which such information will aid the case study countries in fulfilling obligations under the United Nations Conventions on Climate Change, Biodiversity and Land Degradation are also considered. The need for more detailed land management data to improve SOC stock estimates in non-temperate areas is discussed.

The common GIS-based approach to regional analyses of soil organic carbon (SOC) stocks and changes is to define geographic layers for which unique sets of driving variables are derived, which include land use, climate, and soils. These GIS layers, with their associated attribute data, can then be fed into a range of empirical and dynamic models. Common methodologies for collating and formatting regional data sets on land use, climate, and soils were adopted for the project Assessment of Soil Organic Carbon Stocks and Changes at National Scale (GEFSOC). This permitted the development of a uniform protocol for handling the various input for the dynamic GEFSOC Modelling System. Consistent soil data sets for Amazon-Brazil, the Indo-Gangetic Plains (IGP) of India, Jordan and Kenya, the case study areas considered in the GEFSOC project, were prepared using methodologies developed for the World Soils and Terrain Database (SOTER). The approach involved three main stages: (1) compiling new soil geographic and attribute data in SOTER format; (2) using expert estimates and common sense to fill selected gaps in the measured or primary data; (3) using a scheme of taxonomy-based pedotransfer rules and expert-rules to derive soil parameter estimates for similar soil units with missing soil analytical data. The most appropriate approach varied from country to country, depending largely on the overall accessibility and quality of the primary soil data available in the case study areas. The secondary SOTER data sets discussed here are appropriate for a wide range of environmental applications at national scale. These include agro-ecological zoning, land evaluation, modelling of soil C stocks and changes, and studies of soil vulnerability to pollution. Estimates of national-scale stocks of SOC, calculated using SOTER methods, are presented as a first example of database application. Independent estimates of SOC stocks are needed to evaluate the outcome of the GEFSOC Modelling System for current conditions of land use and climate.

The GEFSOC Project developed a system for estimating soil carbon (C) stocks and changes at the national and sub-national scale. As part of the development of the system, the Century ecosystem model was evaluated for its ability to simulate soil organic C (SOC) changes in environmental conditions in the Indo-Gangetic Plains, India (IGP). Two long-term fertilizer trials (LTFT), with all necessary parameters needed to run Century, were used for this purpose: a jute (Corchorus capsularis L.), rice (Oryza sativa L.) and wheat (Triticum aestivum L.) trial at Barrackpore, West Bengal, and a rice-wheat trial at Ludhiana, Punjab. The trials represent two contrasting climates of the IGP, viz. semi-arid, dry with mean annual rainfall (MAR) of 1600 mm. Both trials involved several different treatments with different organic and inorganic fertilizer inputs. In general, the model tended to overestimate treatment effects by approximately 15%. At the semi-arid site, modelled data simulated actual data reasonably well for all treatments, with the control and chemical N + farm yard manure showing the best agreement (RMSE = 7). At the humid site, Century performed less well. This could have been due to a range of factors including site history. During the study, Century was calibrated to simulate crop yields for the two sites considered using data from across the Indian IGP. However, further adjustments may improve model performance at these sites and others in the IGP. The availability of more long-term experimental data sets (especially those involving flooded lowland rice and triple cropping systems from the IGP) for testing and validation is critical to the application of the model's predictive capabilities for this area of the Indian sub-continent.

More than 50 yr ago US soil taxonomy was adopted in India. Since then many researchers have contributed their thoughts to enrich the soil taxonomy. The National Bureau of Soil Survey and Land Use Planning (NBSS & LUP) (Indian Council of Agricultural Research) as a premier soil survey institute has been consistently using benchmark soil series to understand the rationale of the soil taxonomy, keeping in view the soil genesis from different rock systems under various physiographic locations in tropical India. The present review is a humble effort to present this information.

Earlier hypothesis on the factors and processes of natural degradation in Vertisols and also their evaluation for crops on the basis of only hydraulic properties was developed on limited soils by the Division of Soil Resource Studies (DSRS) of the National Bureau of Soil Survey and Land Use Planning (NBSS & LUP), Nagpur, India. In order to validate the above similar soils occurring in major states of the Peninsular India and also to document the extent of modification by gypsum and Ca-zeolites therein, the present study on twenty-six benchmark Vertisols representing a climosequence from sub-humid moist to arid dry climate was undertaken. The results of the present study validates the hypothesis that formation of pedogenic calcium carbonate (PC) at the expense of non-pedogenic calcium carbonate (NPC) is the prime chemical reaction for the natural chemical degradation realized in terms of impairment of hydraulic properties of soils mediated through the development of subsoil sodicity. Presence of gypsum and Ca-zeolites, on the other hand, prevented the rise of pH, decrease in Ca/Mg ratio of exchange sites and improved the hydraulic properties amidst an exchangeable sodium percentage (ESP) > 15. The improvement in saturated hydraulic conductivity (sHC) (> 10 mm h − 1 ) of zeolitic sodic soils does commensurate fairly well with the performance of rainy season crops. Thus characterization of sodic soils in terms of sHC − 1 (weighted mean in 0–100 cm depth of soil) instead of any ESP or sodium adsorption ratio (SAR) emerges as a robust criterion that stands for a universal acceptance for the better use and management of such naturally degraded soils, not only in the Indian semi-arid tropics, but also in similar climatic and geologic areas elsewhere.

In contrast to generally observed non-acidic and less weathered Mollisols in temperate semi-arid and humid climate, acidic and fairly weathered Mollisols on Deccan basalt are observed in hills of central (Satpura Range, Madhya Pradesh) and Western India (Western Ghats, Maharashtra) under forest in the present tropical humid climatic conditions. The detailed morphological, chemical and mineralogical investigations of these Mollisols of central and western India indicates that due to the presence of zeolites in the Deccan basalt, the transformation of smectite to kaolinite was prevented and the retention of adequate amount of smectite and continuous supply of calcium ions from zeolites made the formation of Mollisols in forest even under tropical humid climate. The formation and the persistence of these Mollisols in association with acidic Alfisols under sparse forest in the basaltic landscape of millions of years in central and western India demonstrates the primary importance of the quality of parent material rich in expanding clay mineral and bases in their formation. This unique example thus expands the basic knowledge on the formation of Mollisols in the humid tropical part of the world.

In view of diverse understanding on the movement and accumulation of clay particles in calcareous parent material, a micromorphological study on 28 Alfisols of the semiarid part of the Indo-Gangetic Plains (IGP) was undertaken. The study indicates that the identified clay pedofeatures are typically of the type “impure clay pedofeatures” which have resulted from the impairment of the parallel orientation of the clay platelets induced by dispersion of both clay and silt size layer silicates in slightly to highly sodic environment. The study also indicates that the illuviation of clay particles and their subsequent accumulation in the Bt horizons have occurred in sodic environment caused by the precipitation of soluble Ca 2+ ions as calcium carbonate (CaCO 3 ), thus discounting any role of soluble Ca 2+ ions and the presence of CaCO 3 in preventing the movement and accumulation of clay particles. The study thus suggests that the formation of impure clay pedofeatures and pedogenic CaCO 3 are two pedogenic processes occurring simultaneously in soils of the IGP as contemporary pedogenic events in the semiarid climate since the last 4000 years B.P.

In the northwestern part of the Indo-Gangetic Plains (IGP), India, non-sodic and moderately sodic soils occur on microhigh (MH) and highly sodic soils on microlow (ML) positions under a semi-arid climate. The main soil-forming processes have been clay illuviation, deposition of pedogenic calcium carbonate and concomitant development of sodicity. The microlows are repeatedly flooded with surface water during brief high-intensity showers, so the soils are subject to cycles of wetting and drying. This provides a steady supply of alkalis by hydrolysis of feldspars, leading to precipitation of calcium carbonate at high pH and development of subsoil sodicity. This impairs the hydraulic conductivity of soils and eventually leads to the development of Natrustalfs with exchangeable sodium percentages increasing rapidly up the profile. The semi-arid climate and topography interact to facilitate greater penetration of bicarbonate-rich water in microlow than microhigh positions. Thin sections show deformational pedofeatures such as cross and reticulate striation of plasmic fabric, disruption of clay pedofeatures and carbonate nodules and elongation of voids as a result of tectonic activity during the Holocene. In view of the persistent build up of stresses in the IGP in general, and the study area in particular, it seems that the neotectonics have caused the microtopographical variations (0.5–1 m) that control the formation of sodic soils.

Micromorphological studies were performed in order to understand the factors and processes involved in the formation of calcium carbonate (CaCO3) in twenty three soil series of Vertisols representing sub-humid, semi-arid and arid climatic regions of Peninsular India. The study indicates that Vertisols contain both pedogenic calcium carbonate (PC) and non-pedogenic calcium carbonate (NPC) irrespective of the ecosystems to which they belong. The NPCs are part of the parent material of Vertisols. Dissolution of NPCs and recrystallization of dissolved Ca2+ ions are responsible for the formation of PCs. Vertisols of arid and semi-arid climates contain more PC in their soil control section (SCS) than those of sub-humid climates. Formation of PC is the prime chemical reaction responsible for the increase in pH, the decrease in the Ca/Mg ratio of exchange site with depth and in the development of subsoil sodicity. Petrographic and scanning electron microscopic (SEM) examination of quartz, feldspars and micas indicate little or no alteration, discounting the possibile formation of smectite during Vertisol formation. X-ray diffraction (XRD) analysis of clays indicates that smectites of Vertisols are fairly well crystallized and do not show any sign of transformation except for hydroxy interlayering. The preservation of the crystallinity of smectite and the lack of transformation of primary minerals thus validate the hypothesis of positive entropy change during the formation of Vertisols. The precise cause-effect relationship between CaCO3 of pedogenic and non-pedogenic origin, and exchangeable Mg, Na and Ca percentages (EMP, ESP and ECP) has been established in the study. This indicates that impoverishment of Ca2+ ions on the exchange sites of Vertisols needs to be controlled by rehabilitation methods that can replenish Ca2+ ions, and thus the study provides relevant information for future land resource management programmes not only on Vertisols of India but also on similar soils occurring elsewhere.

Previous studies have shown an association between duration of bisphosphonate use and atypical femur fractures. This cohort study showed an increasingly higher risk of subtrochanteric and femoral shaft fractures among those who were more adherent to oral bisphosphonates.Long-term use of oral bisphosphonates has been implicated in an increased risk of atypical femur fractures located in subtrochanteric and femoral shaft regions. Another measure of drug exposure, medication adherence, however, has not been investigated.Among all Medicare fee-for-service female beneficiaries from 2006-2010, we followed 522,287 new bisphosphonate users from their index prescription until being censored or having a primary diagnosis of closed subtrochanteric/femoral shaft or intertrochanteric/femoral neck fractures. Data about radiographs of fracture site and features were not available. Adherence was classified according to the medication possession ratio (MPR) as the following: MPR 1/3 as less compliant, MPR ≥ 1/3- 2/3 as compliant, and MPR ≥ 2/3 as highly compliant. Alternative cutoff points at 50 and 80% were also used. Survival analysis was used to determine the cumulative incidence and hazard of subtrochanteric/femoral shaft or intertrochanteric/femoral neck fractures.There was a graded increase in incidence of subtrochanteric/femoral shaft fractures as the level of adherence increased (Gray's test, P 0.001). The adjusted hazard ratio (HR) for the highly compliant vs. the less compliant was 1.23 (95% Confidence Interval [CI] 1.06-1.43) overall, became significant after 2 years of follow-up (HR = 1.51, 95% CI 1.06-2.15) and reached the highest risk in the fifth year (HR = 4.06, 95% CI 1.47-11.19). However, age-adjusted incidence rates of intertrochanteric/femoral neck fractures were significantly lower among highly compliant beneficiaries, compared to less compliant users (HR = 0.69, 95% CI 0.66-0.73). Similar results were obtained when the cutoff points for being compliant and highly compliant were set at 50 and 80 %, respectively.Subtrochanteric/femoral shaft fractures, unlike intertrochanteric/femoral neck fractures, are positively associated with higher adherence to long-term (≥3 years) oral bisphosphonates in the elderly female Medicare population.

Although the major soils of India (alluvial, ferruginous and black soils), endowed with fine-grained micas, are known as natural K suppliers to plants, crop response to K fertilizer treatment has been anomalous. The silt and clay fractions of 14 benchmark soils were subjected to repeated batch type Ba–K exchange to study the rate of K release. The significant positive correlation between cumulative K release in 25 extractions and X-ray intensity ratio of peak heights of the 001 and 002 basal reflections of mica in the silt ( r =0.629 at 1% level) and clay ( r =0.729 at 1% level) suggested that although the fine-grained muscovite and biotite co-exist in soils, the rate of K release and crop response to K are related primarily to the presence of biotite only while muscovite remains as an inert source of K in soils justifying the crop response to K fertilizers. Soil micas under a scanning electron microscope (SEM) indicated that biotite particles were generally thick, showing layer separation with bending at edges due to the formation of vermiculite around their rims. The muscovites, on the other hand, were characterized by very minor layer separation at their edges. To resolve the issue of layer separation of micas through the release of K during the formation of soils, experimental studies of repeated Ba–K exchange were conducted with specimen muscovite and biotite and also on the mixture of the two micas. Experimental studies indicated that at ambient temperature and pressure, muscovite released negligible amount of K from its exposed surfaces and the weathering of muscovite was inhibited in the presence of biotite. This confirmed the observation that when muscovite and biotite co-exist, muscovite hardly weathers in soil environments. Hence, its enrichment in soils does not enhance the supply of K. Therefore, weathering products like di- and trioctahedral vermiculite and smectite are generally the products of the weathering of biotite mica. The X-ray intensity ratio of 001 and 002 basal reflections of mica has been found to be an effective diagnostic parameter to find out the quality of mica and therefore to judge the K releasing potential of soils. However, actual quantification of fine-grained biotites of soils appears to be mandatory for the precise determination of K reserves in soils in order to predict release of K for sustainable K management.

There are two different views regarding the genesis of gibbsite in tropical acid soils: (1) direct weathering of primary Al-silicate minerals; and (2) transformation through clay mineral intermediates. We investigated the genesis of gibbsite in two representative Ultisols from northeastern India. Gibbsite in these Ultisols appears to be the remnant of earlier weathering products of aluminosilicate minerals formed in a neutral to alkaline pedochemical environment. The mere presence of gibbsite in these soils, therefore, does not indicate their advanced stage of weathering. The formation of typically rod-shaped and well-crystallized gibbsite in both the coarse and fine soil fractions in the presence of large amounts of 2:1 minerals indicates that the anti-gibbsite hypothesis may not be tenable in these tropical acid soils. A schematic model for the formation of gibbsite and kaolin in Ultisols is proposed.

The high altitude ferruginous Alfisols associated spatially with shrink–swell soils on the Deccan basalt plateau and dissected table lands in the Western Ghats of India were analysed for their morphological, chemical and mineralogical properties with a view to comprehend their formation and persistence in the tropical humid climate prevailing since the early Tertiary. The study indicates that despite their acidic pH the soils have high bases and their clay fractions are dominated by interstratified smectite-kaolin. The persistence of these non-kaolinitic and/or non-oxidic Alfisols has been possible due to the presence of base-rich zeolites of amygdoloidal basalt. It suggests that for an open system such as soil, the existence of steady state is a more meaningful concept than thermodynamic equilibrium. The knowledge gained on the role of zeolites in soils provides a check on the reasoning of models on the formation of soils in tropical humid climate. The study also indicates that the supply of bases from zeolites can prevent the soils from losing their productivity even in intense leaching environment.