Drought is the major precipitation anomaly that has greater impact on water resource management, ground water table and agricultural production. The WASP index (Weighted Anomaly of Standardized Precipitation Index) was estimated for a period 1901-2019 (119 years) – four time scales (12 months, 9 months, 6 months and 3 months) based on the IMD precipitation dataset to analyse the dry events. Analysis over different time scales is necessary to find out the impact of the slowly evolving drought on the agricultural production as well as water resources. The numbers of moderate dry events were 276, 256, 188 and 100 for WASP12, WASP9, WASP6, and WASP3 respectively for the whole of 119 years data. The number of extreme dry events with WASP12, WASP9, WASP6, and WASP3 were 0, 4, 29 and 59, respectively, for 119 years. There was no specific trend in number of dry events over the study region and 1991-2019 was found to have higher number of dry events when compared with the other tri-decadal periods.
Rainfall is the most dependent weather factor that decides the success or failure of a crop in a location. The behaviour of rainfall plays a major role in the selection of crop, cropping system and cropping pattern. It is also essential for planning of water resource management structures. Hence it is essential to study the anomaly in rainfall over a long period of time to identify the deviation in rainfall pattern over the region. Weighted Anomaly of Standardized Precipitation Index (WASP) is an index that can help in identifying the occurrence of dry or wet spells over different time scales (tri, hexa, nona and dodeca-monthly). The analysis was carried out for Salem district of Tamil Nadu over a period of 30 years (1991-2020) which has an average rainfall of 990 mm per year with bimodal distribution. The analysis shows an increase in near normal events, decrease in wet as well as dry events with 3 m, 6 m, 9 m and 12 m WASP. The 3 m-WASP indicates the north east monsoon have more variability in rainfall since more number of wet as well as dry events have occurred during this season. With 6 m WASP During, in all the 3 decades, the consecutive wet as well as dry events have been occurred during the winter and NE monsoon seasons. This shows the risk in crop cultivation during NEM season because of higher instability in rainfall. Considering the longer time scale of 9 m and 12 m WASP indicates the occurrence of prolonged extreme dry or extreme wet events to be very minimal. The negative effects of these events can be handled easily by adopting proper drainage, water harvesting and storage structure within the farms. These structures can also help in recharging the ground water table in addition to supplementing water needs for the crops.
The study on the effect of soil amendments and fertilizers on the mitigation of CH4 and N2O emission from rice field was conducted in the Wetland farm of Tamil Nadu Agricultural University farm, Coimbatore, Tamil Nadu, India during rabi season. The results showed that the use of Gypsum and Fly Ash along with recommended dose of fertilizer reduced the emission of methane whereas urea with neem treatment reduced the N2O emission from the conventional water logged rice field. Methane emission was found to peak during the panicle initiation stage while nitrous oxide emission was noted only during the maturity stage. The application of Fly Ash along with gypsum had cut down the methane emission to a greater extent at all the stages. Nitrous oxide emission was reduced with the application of slow release N fertilizer (neem treated urea).
Climate change is no longer a distinct prognosis but become a reality and also proved to have its impacts on crop production. Blackgram, a C3 short duration pulse crop was considered for this study to clarify the controversial statements on adaptability of this crop for changing climate. Dynamically downscaled data (CCSM4 data using REGCM4.4 model) for 1971 to 2099 (RCP 4.5 scenario) was used for the study. The popular cultivars CO6 and VBN6 of Blackgram are employed for the study after calibration and validation of DSSAT model. The impact assessment was carried out with August 1st as sowing date. The yield of Blackgram was found to have beneficial stimulus towards the changing climate under enriched CO2. Considering cultivars, difference was noticed spatially and temporally. The average yield of VBN6 was less than CO6 during base and near century, but it got reverse with time.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.