This study was conducted over 3 years in a salt-affected coastal rainfed lowland ecosystem. Farme... more This study was conducted over 3 years in a salt-affected coastal rainfed lowland ecosystem. Farmers most commonly grow tall rice varieties in the wet season to cope with flash and/or stagnant floods, leading to large amounts of rice residue production. Most of the land remains fallow during the dry season because of increased salinity and scarcity of freshwater for irrigation. The study aims to provide options for increasing cropping intensity through management of crop residues (CR) and soil salinity, conservation of soil moisture, and reduction in production cost. The rice–maize rotation was assessed with rice as the main plot as (1) puddled transplanted rice (PTR) with CR of both rice and maize removed, (2) PTR and 40% CR of both crops retained, (3) dry direct-seeded rice (DSR) with CR of both crops removed, and (4) DSR with 40% CR of both crops retained. Maize in the dry season was supplied with different N levels as sub-plots—control (0 kg N ha−1), 80, 120, and 160 kg N ha−1. D...
A study was conducted to assess the status of available secondary nutrients (Ca, Mg and S) along ... more A study was conducted to assess the status of available secondary nutrients (Ca, Mg and S) along with physico-chemical properties of soils under continuous vegetable based cropping systems at the Central Research Farm of Indian Institute of Vegetable Research, Varanasi situated at 82.52°E longitude and 25.10°N latitude in the alluvial belt of Indo-Gangetic Plains (IGP) of Eastern Uttar Pradesh. The soils at this farm have been under continuous vegetable cultivation with the exception of intermittent cultivation of paddy in some blocks for the last 15 years. The experimental farm has a total area of 45 ha spread over 16 blocks. The analysis of 360 soil samples collected from different blocs for various physico-chemical properties and status of secondary nutrients reveal that the soils of the research farm were neutral to slightly alkaline in reaction having pH in the range of 6.61 to 7.82 with a mean value of 7.29. Electrical conductivity was found within the normal limits (ranged from 0.09 to 0.76 dSm -1 with a mean value of 0.28 dSm -1 ). Twenty two per cent soil samples of the research farm were found in low, 73 per cent in medium and rest 5 per cent in high range of organic carbon content. The bulk density of the soils ranged from 1.31 to 1.58 Mgm -3 with an average of 1.45 Mgm -3 . Water retention at field capacity and permanent wilting points was 25.6 and 6.3 per cent, respectively, and available water content was estimated to be 19.4 per cent. The soils of the entire farm were found to be silt loam in texture. Among the secondary nutrients, available calcium ranged from 1206 to 2302 ppm whereas available magnesium ranged from 164 to 723 ppm which indicates that these soils are sufficient in calcium and magnesium. With regard to the status of available sulfur, 3 per cent soils were found to be in low, 13 per cent in medium and 84 per cent in high range.
North-East India is known for its complex, diverse, risk-prone, and fragile hilly ecosystem. Natu... more North-East India is known for its complex, diverse, risk-prone, and fragile hilly ecosystem. Natural resources in terms of soil, water, vegetation, and soil organic carbon (SOC) are much degraded. Effects of long-term perennial grasses maintained at a permanent fodder block of the ICAR Research Complex, Meghalaya, on soil quality were examined after 15 cropping cycles. The aims were (i) to ascertain whether perennial grass primarily maintained as fodder source for ruminants could conserve resources and improve soil quality in the hilly ecosystem of North-East India, and (ii) to select a suitable perennial grass to minimise land degradation, restore SOC, and improve the soil quality. Soil samples were collected in 2007–08 (dry season) from plots of 8 perennial grasses [Setaria sphacelata (setaria), Brachieria rosenesis (congosignal), Thysanolaena maxima (broom), Penicum maximum var. Makunia and var. Hamil (guinea), Pennisetum purpureum (napier), Paspalum conjugalum (paspalam), Arachi...
An experiment was conducted to study the effect of drip irrigation quantity and mulching on crop ... more An experiment was conducted to study the effect of drip irrigation quantity and mulching on crop growth, yield and water use efficiency (WUE) of tomato grown during the rabi seasons of 2007 and 2008. Two levels of drip irrigation (I1, irrigation withV volume of water; I2, with 0.5V volume of water) and four types of plastic mulch (M0, without mulch; M1, yellow polythene; M2, transparent polythene; M3 black polythene) treatments were applied to tomato planted on a sandy loam soil. Results indicated that the photosynthetic traits such as; chlorophyll content, initial fluorescence (F0), and maximum quantum yield of photosystem II (Fv/Fm) were significantly higher under I1 and black polythene mulch. Dry matter production under drip irrigation with V (˜100% PE) quantity of water was 33.2% more than with 0.5V. Polythene mulching remarkably improved the plant biomass, and plants mulched with black polythene registered 94.7% higher dry matter over unmulched control. Drip irrigation with V quantity of water (I1) resulted in significantly higher fruit yield (2.71 kg/plant and 847.52 q/ha). Maximum fruit yield (2.66 kg/plant and 851.59 q/ha) was recorded with black polythene mulch. Weed growth under 0.5 V (I2) was significantly lower (25% less) than I1. All kinds of plastic mulches gave significant weed control, however, the highest weed reduction (89% over control) was observed with black polythene mulch. Maximum WUE of 49.60 kg/mm-ha was obtained in I2, whereas, among mulches WUE was maximum with black polythene (46.03 kg/mm-ha).
International Journal of Agriculture, Environment and Biotechnology, 2014
Morphometric analysis of a hilly watershed was carried out using GIS. The drainage map generated ... more Morphometric analysis of a hilly watershed was carried out using GIS. The drainage map generated from the Survey of India toposheets was used for morphometric analysis of the watershed in terms of stream order, stream length, bifurcation ratio, relief ratio, drainage density, stream frequency, drainage texture, form factor, circulatory ratio, elongation ratio, infiltration number and ruggedness number. The Um Shipra watershed is a fifth order watershed having dendritic drainage pattern with high drainage density (6.22 km.km-2). The logarithmic plot of the stream length versus stream order showed a linear relationship indicating the watershed has developed over a homogeneous rock material. The mean bifurcation ratio of 1.71 indicated absence of strong structural control on the drainage pattern and that the watershed was structurally less disturbed. The number of streams belonging to the order I, II, III, IV and V were found to be 327, 147, 78, 45 and 46 respectively. Lower values of form factor (0.19), circularity ratio (0.29) and elongation ratio (0.49) suggested that the watershed has elongated shape with lower peak flows for longer duration. The ruggedness number having relatively higher value implied that the area has rugged topography which is prone to soil erosion. Higher values of stream frequency and drainage density indicated that the watershed has high runoff potential despite having lower peak flow creating a good scope for surface water resource development. The results obtained can serve as a useful input for developing soil and water resources conservation and management plan on a watershed basis. Highlights • Geomorphometric analysis of a hilly watershed was carried out in a GIS environment. • Analysis of the morphometric parameters indicated that the watershed has undulated terrain, is prone to erosion and has high runoff potential with lower peak flow offering a good scope for development of surface water resources.
This study was conducted over 3 years in a salt-affected coastal rainfed lowland ecosystem. Farme... more This study was conducted over 3 years in a salt-affected coastal rainfed lowland ecosystem. Farmers most commonly grow tall rice varieties in the wet season to cope with flash and/or stagnant floods, leading to large amounts of rice residue production. Most of the land remains fallow during the dry season because of increased salinity and scarcity of freshwater for irrigation. The study aims to provide options for increasing cropping intensity through management of crop residues (CR) and soil salinity, conservation of soil moisture, and reduction in production cost. The rice–maize rotation was assessed with rice as the main plot as (1) puddled transplanted rice (PTR) with CR of both rice and maize removed, (2) PTR and 40% CR of both crops retained, (3) dry direct-seeded rice (DSR) with CR of both crops removed, and (4) DSR with 40% CR of both crops retained. Maize in the dry season was supplied with different N levels as sub-plots—control (0 kg N ha−1), 80, 120, and 160 kg N ha−1. D...
A study was conducted to assess the status of available secondary nutrients (Ca, Mg and S) along ... more A study was conducted to assess the status of available secondary nutrients (Ca, Mg and S) along with physico-chemical properties of soils under continuous vegetable based cropping systems at the Central Research Farm of Indian Institute of Vegetable Research, Varanasi situated at 82.52°E longitude and 25.10°N latitude in the alluvial belt of Indo-Gangetic Plains (IGP) of Eastern Uttar Pradesh. The soils at this farm have been under continuous vegetable cultivation with the exception of intermittent cultivation of paddy in some blocks for the last 15 years. The experimental farm has a total area of 45 ha spread over 16 blocks. The analysis of 360 soil samples collected from different blocs for various physico-chemical properties and status of secondary nutrients reveal that the soils of the research farm were neutral to slightly alkaline in reaction having pH in the range of 6.61 to 7.82 with a mean value of 7.29. Electrical conductivity was found within the normal limits (ranged from 0.09 to 0.76 dSm -1 with a mean value of 0.28 dSm -1 ). Twenty two per cent soil samples of the research farm were found in low, 73 per cent in medium and rest 5 per cent in high range of organic carbon content. The bulk density of the soils ranged from 1.31 to 1.58 Mgm -3 with an average of 1.45 Mgm -3 . Water retention at field capacity and permanent wilting points was 25.6 and 6.3 per cent, respectively, and available water content was estimated to be 19.4 per cent. The soils of the entire farm were found to be silt loam in texture. Among the secondary nutrients, available calcium ranged from 1206 to 2302 ppm whereas available magnesium ranged from 164 to 723 ppm which indicates that these soils are sufficient in calcium and magnesium. With regard to the status of available sulfur, 3 per cent soils were found to be in low, 13 per cent in medium and 84 per cent in high range.
North-East India is known for its complex, diverse, risk-prone, and fragile hilly ecosystem. Natu... more North-East India is known for its complex, diverse, risk-prone, and fragile hilly ecosystem. Natural resources in terms of soil, water, vegetation, and soil organic carbon (SOC) are much degraded. Effects of long-term perennial grasses maintained at a permanent fodder block of the ICAR Research Complex, Meghalaya, on soil quality were examined after 15 cropping cycles. The aims were (i) to ascertain whether perennial grass primarily maintained as fodder source for ruminants could conserve resources and improve soil quality in the hilly ecosystem of North-East India, and (ii) to select a suitable perennial grass to minimise land degradation, restore SOC, and improve the soil quality. Soil samples were collected in 2007–08 (dry season) from plots of 8 perennial grasses [Setaria sphacelata (setaria), Brachieria rosenesis (congosignal), Thysanolaena maxima (broom), Penicum maximum var. Makunia and var. Hamil (guinea), Pennisetum purpureum (napier), Paspalum conjugalum (paspalam), Arachi...
An experiment was conducted to study the effect of drip irrigation quantity and mulching on crop ... more An experiment was conducted to study the effect of drip irrigation quantity and mulching on crop growth, yield and water use efficiency (WUE) of tomato grown during the rabi seasons of 2007 and 2008. Two levels of drip irrigation (I1, irrigation withV volume of water; I2, with 0.5V volume of water) and four types of plastic mulch (M0, without mulch; M1, yellow polythene; M2, transparent polythene; M3 black polythene) treatments were applied to tomato planted on a sandy loam soil. Results indicated that the photosynthetic traits such as; chlorophyll content, initial fluorescence (F0), and maximum quantum yield of photosystem II (Fv/Fm) were significantly higher under I1 and black polythene mulch. Dry matter production under drip irrigation with V (˜100% PE) quantity of water was 33.2% more than with 0.5V. Polythene mulching remarkably improved the plant biomass, and plants mulched with black polythene registered 94.7% higher dry matter over unmulched control. Drip irrigation with V quantity of water (I1) resulted in significantly higher fruit yield (2.71 kg/plant and 847.52 q/ha). Maximum fruit yield (2.66 kg/plant and 851.59 q/ha) was recorded with black polythene mulch. Weed growth under 0.5 V (I2) was significantly lower (25% less) than I1. All kinds of plastic mulches gave significant weed control, however, the highest weed reduction (89% over control) was observed with black polythene mulch. Maximum WUE of 49.60 kg/mm-ha was obtained in I2, whereas, among mulches WUE was maximum with black polythene (46.03 kg/mm-ha).
International Journal of Agriculture, Environment and Biotechnology, 2014
Morphometric analysis of a hilly watershed was carried out using GIS. The drainage map generated ... more Morphometric analysis of a hilly watershed was carried out using GIS. The drainage map generated from the Survey of India toposheets was used for morphometric analysis of the watershed in terms of stream order, stream length, bifurcation ratio, relief ratio, drainage density, stream frequency, drainage texture, form factor, circulatory ratio, elongation ratio, infiltration number and ruggedness number. The Um Shipra watershed is a fifth order watershed having dendritic drainage pattern with high drainage density (6.22 km.km-2). The logarithmic plot of the stream length versus stream order showed a linear relationship indicating the watershed has developed over a homogeneous rock material. The mean bifurcation ratio of 1.71 indicated absence of strong structural control on the drainage pattern and that the watershed was structurally less disturbed. The number of streams belonging to the order I, II, III, IV and V were found to be 327, 147, 78, 45 and 46 respectively. Lower values of form factor (0.19), circularity ratio (0.29) and elongation ratio (0.49) suggested that the watershed has elongated shape with lower peak flows for longer duration. The ruggedness number having relatively higher value implied that the area has rugged topography which is prone to soil erosion. Higher values of stream frequency and drainage density indicated that the watershed has high runoff potential despite having lower peak flow creating a good scope for surface water resource development. The results obtained can serve as a useful input for developing soil and water resources conservation and management plan on a watershed basis. Highlights • Geomorphometric analysis of a hilly watershed was carried out in a GIS environment. • Analysis of the morphometric parameters indicated that the watershed has undulated terrain, is prone to erosion and has high runoff potential with lower peak flow offering a good scope for development of surface water resources.
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