The study aimed at quantifying the interaction of exposure of wheat to high thermal stress for a ... more The study aimed at quantifying the interaction of exposure of wheat to high thermal stress for a specific duration during the reproductive stage with yield over north western plain zones of India. Thermal stress duration of at least of continuous five days, where average daily temperature positively depart by ≥ 2 0C above long term normal were correlated with annual wheat yield, for two phenological stages, viz. late vegetative and reproductive, under the most ideal location, i.e. Ludhiana, and were extended to estimate yield in other locations through introduction of a thermal response factor. In the reproductive stage a 10 per cent reduction from the average yield was expected in 10 days of thermal stress for Hisar, 13 days for Karnal and 15 days for Kanpur if exposed to average stress temperature departure of above normal (4.20, 3.63 and 3.54 0C, respectively). Findings suggested that the locations with relatively cooler thermal regimes experience proportionately higher yield los...
The long term rainfall data for Sali rice season (June-November) of Jaintia Hills district, Megha... more The long term rainfall data for Sali rice season (June-November) of Jaintia Hills district, Meghalaya has been analyzed to estimate expected weekly rainfall at various probability levels. Based on expected rainfall at 50 and 75% probability levels and water requirement, a crop calendar for Sali rice has been prepared for the district. The calendar is assumed to be applicable for the whole district irrespective of terrain differences as rice is mostly grown in comparatively plain lands in bunded condition. 22nd to 24th meteorological weeks have been suggested best for sowing/transplanting to avoid any kind of water stress during the critical growth periods. Amount of water required to maintain at least 5 cm of standing water in the field up to the dough stage has also been clacilated.
The high level of agricultural productivity is possible with the supply of all essential nutrient... more The high level of agricultural productivity is possible with the supply of all essential nutrients in a balanced proportions and in adequate amounts when all other factors of production are not restricted. Fertilizers have become an indispensable input of modern agriculture to produce more food grains to feed a growing population. Nitrogen (N), phosphorus (P) and potassium (K) are the three major plant nutrients commonly applied through fertilizers by farmers neglecting the secondary and micronutrients. However, unbalanced fertilization not only leads to low fertilizer use efficiency, but also has environmental and economic consequences.
Potato tuber yield were simulated at Jorhat, Assam under various Representative Concentration Pat... more Potato tuber yield were simulated at Jorhat, Assam under various Representative Concentration Pathways (RCPs) scenarios for 2020, 2050 and 2080 using DSSAT SUBSTOR-Potato model. The model was calibrated and validated for three potato cultivars, viz., Kufri Jyoti, Kufri Pokhraj and Kufri Himalini with the experimental data collected during 2014-15 and 2015-16. Results revealed that if planting is delayed beyond November, all these cultivars are likely to record drastic reduction in tuber yield. Cultivar Kufri Himalini may incur tuber yield loss of 64 per cent in 2020 to 75 per cent in 2080, followed by Kufri Jyoti (57.6% in 2020 to 71.5% in 2080) and Kufri Pokhraj (45.2% in 2020 to 56.2% in 2080). Among the cultivars, Kufri Pokhraj may remain a viable cultivar up to 2050, but Kufri Himalini may lose its sustainability by 2020 itself. Hence, adjustment of planting time and development of improved adaptive potato cultivarsonly will ascertai n future potato production in this region.
Changes in Monsoon Rainfall Pattern in a few Agro-ecological Sub- Regions, 2014
Impacts of climate change are likely to inflict more damage in developing and under-developed cou... more Impacts of climate change are likely to inflict more damage in developing and under-developed countries and these will not be uniform across the regions. Hence, it is essential to study the change at regional/local level. In this paper, we have studied the behaviour of rainfall during the summer monsoon period using standardized precipitation index (SPI) at diversified locations under different agro-ecological subregions. This index has the advantage of monitoring and detecting both droughts and floods at different time scales and is also spatially invariant. This is a comparative study, involving gridded data, at two temporal levels: baseline (1951-1990) and current (1991-2007) period. The analysis revealed complete reversal of monsoon rainfall pattern in some locations and change in magnitude of wetness/dryness during kharif and affecting the normal course of agricultural practices.
Due to the shifting course of the Brahmaputra River, the fluvial landforms of the Brahmaputra Val... more Due to the shifting course of the Brahmaputra River, the fluvial landforms of the Brahmaputra Valley of Assam, India, are prone to changes in landform and land use. For sustainable soil management under such conditions, it is crucial to have information about soil physicochemical and biological properties for different land uses. Therefore, the present study was conducted to investigate the soil physicochemical properties and soil microbial population across five major land uses under different landforms, such as paddy fields, banana systems, and arecanut cultivations in the alluvial plains; and rubber plantations and sal forests in the uplands, with varying slope gradients and soil depths (0–25 cm and 25–50 cm) in the lower Brahmaputra Valley. The results of the analysis of variance revealed that the effects of different landforms and land uses were found to be statistically significant on very labile soil organic carbon (VLSOC), available K, B, Fe, Mn, Zn, and Cu, and soil moistur...
Weather and climate greatly influence the agricultural productivity in any region. Agricultural p... more Weather and climate greatly influence the agricultural productivity in any region. Agricultural production and productivity of any region is being regulated by the prevailing climate of that area through temperature, rainfall, light intensity, radiation, sunshine duration etc. The importance of temperature and humidity in enhancing plant nutrient availability and absorption and also the role they play in disease and pest infestation is well documented. Relationship between two or more weather parameters and grain yield of crops can be used for yield prediction well before the actual harvesting of the crops. The unusual weather during reproductive period of a crop adversely affects the crop productivity. In recent years untimely rainfall during maturity period has affected rice and wheat cropping system. Although the climate is the least manageable part of environmental resources, yet a better understanding of the climatic resources and their interactions with agricultural parameters...
International Journal of Agriculture, Environment and Biotechnology
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.
The study aimed at quantifying the interaction of exposure of wheat to high thermal stress for a ... more The study aimed at quantifying the interaction of exposure of wheat to high thermal stress for a specific duration during the reproductive stage with yield over north western plain zones of India. Thermal stress duration of at least of continuous five days, where average daily temperature positively depart by ≥ 2 0C above long term normal were correlated with annual wheat yield, for two phenological stages, viz. late vegetative and reproductive, under the most ideal location, i.e. Ludhiana, and were extended to estimate yield in other locations through introduction of a thermal response factor. In the reproductive stage a 10 per cent reduction from the average yield was expected in 10 days of thermal stress for Hisar, 13 days for Karnal and 15 days for Kanpur if exposed to average stress temperature departure of above normal (4.20, 3.63 and 3.54 0C, respectively). Findings suggested that the locations with relatively cooler thermal regimes experience proportionately higher yield los...
The long term rainfall data for Sali rice season (June-November) of Jaintia Hills district, Megha... more The long term rainfall data for Sali rice season (June-November) of Jaintia Hills district, Meghalaya has been analyzed to estimate expected weekly rainfall at various probability levels. Based on expected rainfall at 50 and 75% probability levels and water requirement, a crop calendar for Sali rice has been prepared for the district. The calendar is assumed to be applicable for the whole district irrespective of terrain differences as rice is mostly grown in comparatively plain lands in bunded condition. 22nd to 24th meteorological weeks have been suggested best for sowing/transplanting to avoid any kind of water stress during the critical growth periods. Amount of water required to maintain at least 5 cm of standing water in the field up to the dough stage has also been clacilated.
The high level of agricultural productivity is possible with the supply of all essential nutrient... more The high level of agricultural productivity is possible with the supply of all essential nutrients in a balanced proportions and in adequate amounts when all other factors of production are not restricted. Fertilizers have become an indispensable input of modern agriculture to produce more food grains to feed a growing population. Nitrogen (N), phosphorus (P) and potassium (K) are the three major plant nutrients commonly applied through fertilizers by farmers neglecting the secondary and micronutrients. However, unbalanced fertilization not only leads to low fertilizer use efficiency, but also has environmental and economic consequences.
Potato tuber yield were simulated at Jorhat, Assam under various Representative Concentration Pat... more Potato tuber yield were simulated at Jorhat, Assam under various Representative Concentration Pathways (RCPs) scenarios for 2020, 2050 and 2080 using DSSAT SUBSTOR-Potato model. The model was calibrated and validated for three potato cultivars, viz., Kufri Jyoti, Kufri Pokhraj and Kufri Himalini with the experimental data collected during 2014-15 and 2015-16. Results revealed that if planting is delayed beyond November, all these cultivars are likely to record drastic reduction in tuber yield. Cultivar Kufri Himalini may incur tuber yield loss of 64 per cent in 2020 to 75 per cent in 2080, followed by Kufri Jyoti (57.6% in 2020 to 71.5% in 2080) and Kufri Pokhraj (45.2% in 2020 to 56.2% in 2080). Among the cultivars, Kufri Pokhraj may remain a viable cultivar up to 2050, but Kufri Himalini may lose its sustainability by 2020 itself. Hence, adjustment of planting time and development of improved adaptive potato cultivarsonly will ascertai n future potato production in this region.
Changes in Monsoon Rainfall Pattern in a few Agro-ecological Sub- Regions, 2014
Impacts of climate change are likely to inflict more damage in developing and under-developed cou... more Impacts of climate change are likely to inflict more damage in developing and under-developed countries and these will not be uniform across the regions. Hence, it is essential to study the change at regional/local level. In this paper, we have studied the behaviour of rainfall during the summer monsoon period using standardized precipitation index (SPI) at diversified locations under different agro-ecological subregions. This index has the advantage of monitoring and detecting both droughts and floods at different time scales and is also spatially invariant. This is a comparative study, involving gridded data, at two temporal levels: baseline (1951-1990) and current (1991-2007) period. The analysis revealed complete reversal of monsoon rainfall pattern in some locations and change in magnitude of wetness/dryness during kharif and affecting the normal course of agricultural practices.
Due to the shifting course of the Brahmaputra River, the fluvial landforms of the Brahmaputra Val... more Due to the shifting course of the Brahmaputra River, the fluvial landforms of the Brahmaputra Valley of Assam, India, are prone to changes in landform and land use. For sustainable soil management under such conditions, it is crucial to have information about soil physicochemical and biological properties for different land uses. Therefore, the present study was conducted to investigate the soil physicochemical properties and soil microbial population across five major land uses under different landforms, such as paddy fields, banana systems, and arecanut cultivations in the alluvial plains; and rubber plantations and sal forests in the uplands, with varying slope gradients and soil depths (0–25 cm and 25–50 cm) in the lower Brahmaputra Valley. The results of the analysis of variance revealed that the effects of different landforms and land uses were found to be statistically significant on very labile soil organic carbon (VLSOC), available K, B, Fe, Mn, Zn, and Cu, and soil moistur...
Weather and climate greatly influence the agricultural productivity in any region. Agricultural p... more Weather and climate greatly influence the agricultural productivity in any region. Agricultural production and productivity of any region is being regulated by the prevailing climate of that area through temperature, rainfall, light intensity, radiation, sunshine duration etc. The importance of temperature and humidity in enhancing plant nutrient availability and absorption and also the role they play in disease and pest infestation is well documented. Relationship between two or more weather parameters and grain yield of crops can be used for yield prediction well before the actual harvesting of the crops. The unusual weather during reproductive period of a crop adversely affects the crop productivity. In recent years untimely rainfall during maturity period has affected rice and wheat cropping system. Although the climate is the least manageable part of environmental resources, yet a better understanding of the climatic resources and their interactions with agricultural parameters...
International Journal of Agriculture, Environment and Biotechnology
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.
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