Actual impacts of global warming on winter wheat yield in Eastern Himalayas

Abstract

<span>Himalayas, are among the areas most vulnerable to global warming, however, little is known<br /><span>about warming impacts on the crops. Therefore, the actual affects of anticipated warming on<br /><span>winter wheat were tested in Tibet, China. During the period 1988-2012, Tibet region has<br /><span>experienced a large increase in daily mean, minimum and maximum temperatures during wheat<br /><span>growing seasons by 0.50, 0.67 and 0.51 <span>o<span>C every ten years, respectively. The de-trended wheat<br /><span>yield increased by 34.4 kg ha<span>-1 <span>year<span>-1 <span>during this period. According to the historical data, 1 <span>o<span>C<br /><span>increase in daily mean temperature could get 370.6 kg ha<span>−1 <span>gain in wheat yield. Similar gains in<br /><span>wheat yield were found in a field warming experiment with an increase of 1.1 <span>o<span>C in daily mean<br /><span>temperature. The field warming caused a significant reduction in the pre-anthesis phase and<br /><span>entire growth period by 14 and 13 days, respectively. The green leaf areas and spike number in<br /><span>the warmed plots were significantly higher than that in non-warmed plots, while the grain<br /><span>number per spike was significantly lower in the former than the later (P<0.05). The main<br /><span>mechanism underlying the positive affects of this moderate warming on wheat yield is through<br /><span>improving plant development and growth during the pre-anthesis phase by mitigating the low<br /><span>temperature limitation. This study suggests that further efforts should be directed towards the<br /><span>improvement on agriculture infrastructure to utilize the positive affects of climatic warming on<br /><span>crop production.</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><br /><br class="Apple-interchange-newline" /></span></span></span></span></span></span></span></span></span></span></span></span></span>