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21.
Soil infiltration, runoff and sediment yield from a shallow soil with varied stone cover and intensity of rain 总被引:6,自引:0,他引:6
Uttam Kumar Mandal K. V. Rao P. K. Mishra K. P. R. Vittal K. L. Sharma B. Narsimlu & K. Venkanna 《European Journal of Soil Science》2005,56(4):435-443
Stones on the surface of the soil enhance infiltration and protect the soil against erosion. They are often removed in modern mechanized agriculture, with unfortunate side‐effects. We evaluated experimentally the influence of surface stones on infiltration, runoff and erosion under field conditions using a portable rainfall simulator on bare natural soil in semi‐arid tropical India, because modernization and mechanization often lead to removal of these stones in this region. Four fields with varied cover of stones from 3 to 65% were exposed to three rainfall intensities (48.5, 89.2 and 136.8 mm hour?1). Surface stones retarded surface runoff, increased final infiltration rates, and diminished sediment concentration and soil loss. The final infiltration ranged from 26 to 83% of rainfall when the rainfall intensity was 136.8 mm hour?1. The reduction in runoff and soil erosion and increase in infiltration were more pronounced where stones rested on the soil surface than where they were buried in the surface layer. The sediment yield increased from 2 g l?1 for 64.7% stone cover with rainfall of 48.5 mm hour?1 to 70 g l?1 for 3.5% stone cover with rain falling at 136.8 mm hour?1. The soil loss rate was less than 2 t ha?1 hour?1 for the field with stone cover of 64.7% even when the rainfall intensity was increased to 136.8 mm hour?1. The effects of stones on soil loss under the varied rainfall intensities were expressed mathematically. The particles in the sediment that ran off were mostly of silt size. 相似文献
22.
A greenhouse pot experiment was conducted to study the effect of application of three levels of phosphorus (0, 50 and 100 ppm) and three levels of zinc (0, 5 and 10 ppm) in all possible combinations on yield and tissue concentrations of zinc, copper, iron and manganese by rice at two different growth stages (35 and 90 days after transplantation). The results showed that application of both phosphorus and zinc increased the dry matter yield of shoot and root at both the growth stages. Phosphorus or zinc application was found to influence the concentration of zinc, copper, iron and manganese in shoot and in root but these influences varied with the growth stages of the plant as well as with the level of zinc and phosphorus application. The results further showed that phosphorus or zinc application influenced the absorption of zinc/phosphorus, iron, manganese and copper by rice plants and their translocation from root to shoot. Such effects were found to be more prominent at early growth stage than at late growth stage of the plants. 相似文献
23.
K. Abirami Anjali Sharma Jatindra Nath Samanta V. S. Rana Kunal Mandal 《Phytoparasitica》2012,40(5):445-450
Mamejvo (Enicostemma axillare Raynal) is a perennial herb with diversified health benefits. It was found to be affected by a witches?? broom disease under the field conditions at Anand, Gujarat, India. Affected plants were 53.33% reduced in height due to shortened internodes, leading to typical witches?? broom symptoms. Flower size was reduced significantly in the affected plants compared with the healthy ones and their petal color gradually turned green (virescence). Affected plants produced 2.5 times more dry herbage than the normal plants but with less active ingredient (swertiamarin). Symptomatic plants died early while root suckers from such plants failed to establish after transplanting. DAPI stained transverse sections of affected shoot tips showed the presence of discrete greenish fluorescence in the phloem cells under UV light. Amplification of 1.2?kb phytoplasma specific rDNA fragment from diseased tissue confirmed the presence of the pathogen. Further characterization of the pathogen through virtual rDNA?CRFLP pattern and rDNA sequence based phylogeny suggested that the pathogen, Enicostemma witches?? broom phytoplasma, belonged to 16SrII?CC group of ??Ca Phytoplasma aurantifolia??. 相似文献
24.
Ranjan Bhattacharyya Arti Bhatia Birendra N. Ghosh Priyabrata Santra Debashis Mandal Gopal Kumar Raman Jeet Singh Madegowda Madhu Avijit Ghosh Arup K. Mandal Ranjan Paul Ashim Datta Parbodh C. Sharma Uttam K. Mandal Pramod Jha Kokkuvayil S. Anil Manickam Lalitha Mahesh Kumar Nav R. Panwar Dibyendu Sarkar Ashok K. Patra Sumanta Kundu Michael A. Fullen Jean Poesen Bhabani Sankar Das Nagarjuna N. Reddy Suresh K. Chaudhari 《European Journal of Soil Science》2023,74(4):e13388
Current widespread and intensive soil degradation in India has been driven by unprecedented levels of population growth, large-scale industrialization, high-yield agriculture, urban sprawl and the spread of human infrastructure. The damage caused to managed and natural systems by soil degradation threatens livelihoods and local services and leads to national socio-economic disruption. Human-induced soil degradation results from land clearing and deforestation, inappropriate agricultural practices, improper management of industrial effluents and wastes, careless management of forests, surface mining, urban sprawl, and ill-planned commercial and industrial development. Of these, inappropriate agricultural practices, including excessive tillage and use of heavy machinery, over-grazing, excessive and unbalanced use of inorganic fertilizers, poor irrigation and water management techniques, pesticide overuse, inadequate crop residue and/or organic carbon inputs, and poor crop cycle planning, account for nearly 40% (121 Mha) of land degradation across India. Globally, human activities related to agriculture contribute to the transgression of four of the nine Planetary Boundaries proposed by Rockström et al. (2009): Climate Change, Biodiversity Integrity, Land-system Change, and altered Phosphorus and Nitrogen Biogeochemical Flows. This review focuses on how knowledge of soil processes in agriculture has developed in India over the past 10 years, and the potential of soil science to meet the objectives of the United Nations' Sustainable Development Goal 2: Zero Hunger (End hunger, achieve food security, improved nutrition and promote sustainable agriculture), using the context of the four most relevant Planetary Boundaries as a framework. Solutions to mitigate soil degradation and improve soil health in different regions using conservation agricultural approaches have been proposed. Thus, in this review we (1) summarize the outputs of recent innovative research in India that has explored the impacts of soil degradation on four Planetary Boundaries (Climate Change, Biodiversity Loss, Land-system Change, and altered Biogeochemical Flows of Phosphorus and Nitrogen) and vice-versa; and (2) identify the knowledge gaps that require urgent attention to inform developing soil science research agendas in India, to advise policy makers, and to support those whose livelihoods rely on the land. 相似文献
25.
Soil loss tolerance limit is defined as the threshold upper limit of soil erosion that can be allowed without degrading long term productivity of specific soils. In India a default soil loss tolerance limit (SLTL) of 11.2 Mg ha− 1 yr− 1 is followed for planning soil conservation activities. The objective of this investigation is to provide a methodology to estimate quantitative SLTL for the Shivalik–Himalayan region in India for suggesting suitable soil conservation measures. A quantitative model was used to integrate potential soil indicators such as infiltration rate, bulk density, water stable aggregate, organic carbon and fertility status to assess soil quality governing soil resistibility to erosion. Scaling functions were used to convert soil parameters to unit less 0 to 1 scale. Normalized values of soil parameters were then multiplied by assigned weights based on relative importance and sensitivity analysis of each indicator. Soils were grouped into 1, 2 and 3 depending on overall additive score. A general guideline developed by the USDA-Natural Resource Conservation Service (NRCS) was followed with certain modifications in depth category for estimation of SLTLs. Soil loss tolerance limits varied from 2.5 to 12.5 Mg ha− 1 yr − 1 compared to single value of 11.2 Mg ha− 1 yr − 1 being followed earlier. Consideration of the newly estimated SLTLs would facilitate site specific conservation planning and prioritising areas for watershed management activities in India. 相似文献
26.
27.
Effect of different feeds on the growth,survival and reproductive performance of zebrafish,Danio rerio (Hamilton, 1822)
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Present experiment was conducted to determine the effect of different feeds with varying protein levels on the growth, survival and reproductive performance of zebrafish, Danio rerio. The control diet (T1) was wild‐collected zooplankton from local fish ponds, while test diets with 350 g kg?1 protein (T2), 400 g kg?1 protein (T3) and 450 g kg?1 protein (T4) were formulated and fed to fish for a period of 210 days. The significantly (P < 0.05) highest mean weight gain and specific growth rate were observed in T1, which were similar with T3 and T4. The significantly (P < 0.05) highest number of egg production per female and relative fecundity were found in T1, followed by T4 and T3 while T2 produced lowest number of eggs. No significant (P > 0.05) differences were observed in brood survival rate, fertilization and hatching rate among the dietary treatments. The highest (P < 0.05) fry survival rate was recorded in T1, followed by T3 and T4. Thus, it is suggested that control diet i.e. mixed zooplankton exhibited better growth, reproductive performance and fry survival rate. However, diet containing 400 g kg?1 crude protein also gave comparable results in terms of growth, survival and reproductive performance of zebrafish. 相似文献
28.
Effect of irrigation and nitrogen application methods on input use efficiency of wheat under limited water supply in a Vertisol of Central India 总被引:1,自引:0,他引:1
K. K. Bandyopadhyay A. K. Misra P. K. Ghosh K. M. Hati K. G. Mandal M. Moahnty 《Irrigation Science》2010,28(4):285-299
Field experiments were conducted in a deep Vertisol at the Indian Institute of Soil Science, Bhopal during the years 2001–2005
to assess the effect of five different irrigation strategies through combinations of sprinkler and flood irrigation and two
N application methods on yield and water use efficiency of wheat (cv WH 147). The amount of irrigation applied each year differed
according to the availability of water in the water harvesting pond to simulate the actual water crisis faced by the farmers
in this region during these years due to monsoon failure. Results indicated that when wheat was grown only with 8-cm irrigation
at sowing or 14 cm up to the crown root initiation stage, dry sowing of wheat immediately followed by sprinkler and subsequent
irrigation through flooding produced the highest yield and water and nitrogen use efficiencies. However, when 20-cm irrigation
was supplied up to the flowering stage or 14-cm irrigation was supplied up to tillering stage through sprinkler in 4 and 3
splits, respectively, at critical growth stages, maximized the grain yield and water and nitrogen use efficiencies. Across
the years, the crop yield and water and nitrogen use efficiencies increased with increase in water supply. 相似文献
29.
A 3-year study was carried out to assess the root biomass production, crop growth rate, yield attributes, canopy temperature
and water-yield relationships in Indian mustard grown under combinations of irrigation and nutrient application for revealing
the dynamic relationship of crop yield (Y) and seasonal evapotranspiration (ET). Three post-sowing irrigation treatments viz. no irrigation (I
1), one irrigation at flowering (I
2) and two irrigations one each at rosette and flowering stage (I
3), three nutrient treatments viz. no fertilizer or manure (F
1), 100% recommended NPK i.e., 60 kg N, 13.1 kg P and 16.6 kg K ha−1 (F
2) and 100% recommended NPK plus farmyard manure @ 10 Mg ha−1 (F
3) were tested in a split-plot design. Root biomass was significantly greater in I
3 than I
2 and I
1, and in F
3 than F
2 and F
1. The I
3 × F
3, I
2 × F
3 and I
3 × F
2 combinations maintained significantly greater crop growth rate, plant height, yield components, ET and crop yield and better
plant water status in terms of canopy temperature, canopy-air temperature difference (CATD) and relative leaf water content
(RLWC). Number of siliqua plant−1 and seeds siliqua−1 were the major contributors to the seed yield. Marginal analysis of water production function was used to establish Y–ET relationship. The elasticity of water production (E
wp) provides a means to assess relative changes in Y and ET, and gives an indication of improvement of Y due to nutrient application. The ET–Y relationships were linear with marginal water use efficiency (WUEm) of 3.09, 4.23 and 3.95 kg ha−1 mm−1 in F
1, F
2 and F
3, respectively, and the corresponding E
wp were 0.63, 0.71 and 0.61. This implies that the scope for improving yield and WUE with 100% NPK was little compared with
100% NPK + farmyard manure. The crop yield was highest in I
3 × F
3 combination, and the similar yield was obtained in I
2 × F
3 and I
3 × F
2 combinations. Application of organic manure along with 100% NPK fertilizers maintained greater crop growth rate, better water
relation in plants, yield attributes and saved one post-sowing irrigation. 相似文献
30.
Sajal Pati Biplab Pal Shrikant Badole Biswapati Mandal 《Communications in Soil Science and Plant Analysis》2016,47(3):284-290
A field experiment was conducted to study the effect of silicon (diatomaceous earth, DE) fertilization on growth, yield, and nutrient uptake of rice during the kharif season of 2012 and 2013 in the new alluvial zone of West Bengal, India. Results showed that application of silicon significantly increased grain and straw yield as well as yield-attributing parameters such as plant height (cm), number of tillers m?2, number of panicle m?2, and 1000-grain weight (g) of rice. The greatest grain and straw yields were observed in the treatment T6 (DE at 600 kg ha?1 in combination with standard fertilizer practice (SFP). The concentration and uptake of silicon, nitrogen (N), phosphorus (P), and potassium (K) in grain and straw were also greater under this treatment compared to others. It was concluded that application of DE at 600 kg ha?1 along with SFP resulted increased grain, straw, and uptake of NPK. 相似文献