Impact Assessment of Climate Change on Paddy Yield: A Case Study of Nepal Agriculture Research Council (NARC), Tarahara, Nepal

Abstract

Climate change and global warming are burning issues, which significantly threat agriculture and global food security. Change in solar radiation, temperature and precipitation will influence the change in crop yields and hence economy of agriculture. It is possible to understand the phenomenon of climate change on crop production and to develop adaptation strategies for sustainability in food production, using a suitable crop simulation model. CERES-Rice model of DSSAT v4.0 was used to simulate the rice yield of the region under climate change scenarios using the historical weather data at Nepal Agriculture Research Council (NARC) Tarahara (1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008). The Crop Model was calibrated using the experimental crop data, climate data and soil data for two years (2000)(2001) and was validated by using the data of the year 2002 at NARC Tarahara. In this study various scenarios were undertaken to analyze the rice yield. The change in values of weather parameters due to climate change and its effects on the rice yield were studied. It was observed that increase in maximum temperature up to 2°C and 1°C in minimum temperature have positive impact on rice yield but beyond that temperature it was observed negative impact in both cases of paddy production in ambient temperature. Similarly, it was observed that increased in mean temperature, have negative impacts on rice yield. The impact of solar radiation in rice yield was observed positive during the time of study period. Adjustments were made in the fertilizer rate, plant density per square meter, planting date and application of water rate to investigate suitable agronomic options for adaptation under the future climate change scenarios. Highest yield was obtained when the water application was increased up to 3 mm depth and nitrogen application rate was 140 kg/ha respectively.

Impact of elevated temperature on rice productivity: A case of Lalitpur, Nepal

“…Increasing temperature can cause increased spik elet sterility in rice and reduce grain yield (Wassmann & Dobermann, 2007). This might be the reason behind decrease in production when temperature was elevated by 3 0 C. Similar results were reported by Rai et al (2009) and Malla (2008). High temperature damage photosynthetic membranes (thylakoids) and cause chlorophyll loss, decrease leaf photosynthetic rate, increase embryo abortion, lower grain number, and decrease grain filling duration and rates, thus result in lower grain yield (Sultan et al, 2013).…”

People's experience and facts of changing climate: impacts and responses

“…Although rainfall data analysis did not show any distinct trend in the total annual rainfall amount unlike decline perceived, it showed decline in the monthly total rainfall in the months October to March which is the period for winter rainfall implying decrease in winter similar to the perception. Monsoon is the main source of precipitation, which enters the country from Eastern part of Nepal (Rai et al, 2011). It normally starts in the second week of June and reaches full development in July.…”

“…Due to drought condition in 2005/2006, production fell short by 21,553 metric tonnes and by 179,910 metric tonnes in 2006/2007 due to drought and natural calamities. The rising maximum temperature had a negative impact on the rice yield and increase in minimum temperature can also lead to yield decline due to early maturity of the crop (Rai et al, 2011;Lal, 2011). If the increase in minimum temperature is less strong than the increase in maximum temperature, the daily variability of temperature increases which can decline crop yields (Wheeler et al, 2000).…”

Integrating adaptation into REDD+: potential impacts and social return on investment in Setulang, Malinau District, Indonesia

“…Studies in Nepal have shown that an increase in the minimum daily temperature is more risky than an increase in the maximum daily temperature for obtaining high rice yields (Rai et al 2012). In the Philippines, grain yield has been shown to decline by 10% for each 1°C increase in growing-season minimum temperature during the dry cropping period (Peng et al 2004).…”