海口11～4月农业气候资源变化特征分析

Changing Characteristics of Agricultural Climate Resources from November to April in Haikou City

利用海口市琼山气象站1962~2011年间每年11月到次年4月(以下简称11~4月)的气象资料,运用统计学方法,分析海口市11~4月农业气候资源变化趋势与突变特征,探讨海口市农业气候资源的变化规律。结果表明:(1)海口市11~4月热量资源变得更加丰富,平均气温呈显著的上升趋势,趋势率为0.33℃/10a(P【0.01),1963年发生突变;各月平均气温均呈正趋势变化;(2)11~4月总降水量存在不明显的下降趋势,趋势率为-15.6 mm/10a(P】0.1),没有明显的突变点;各月降水量变化趋势不明显,但变率大;(3)11~4月总日照时数呈显著的减少趋势,趋势率为-48.7 h/10a(P【0.01),2001年发生突变;各月日照时数呈减少趋势,容易造成农作物的光合作用不充分,不利于干物质积累,影响农作物产量;(4)温度上升明显,干燥度增大,气候暖干化,加大干旱发生的强度和频率。气候的变化导致农业气候资源的变化,对农作物产生正负效应,了解农业气候资源的变化特征将对充分利用农业气候资源,科学、合理应对气候变化,趋利避害提供帮助。

In order to probe into the variation rules of agricultural climatic resources, the variation trend and sudden change characteristics of agricultural climate resources in Haikou City from November to April are analyzed in this paper by utilizing the data of Qiongshan Meteorological Station in the same period from the year 1962 to 2011 and combining with statistical principles. It turns out that the average temperature of Haikou City from November to April shows a significant rising trend with a rate of 0.33℃/10 a (P<0.01), and a sudden change occurred in 1963; The average temperature of each month presents a positive trend, and heat sources are more enriched. The total precipitation from November to April shows an insignificant downtrend with a rate of -15.6 mm/10 a, and no significant sudden change point is found; the precipitation of each month presents an insignificant variation trend with large variability. The total sunshine hours from November to April shows a significant downtrend with a rate of -48.7 h/10 a (P <0.01), and a sudden change occurred in 2011; The sunshine hours of each month presents a downward trend, which can easily lead to insufficient photosynthesis and the crop yield would be affected due to unfavorable to dry matter accumulation. There is a significant increase in temperature and dryness together with warm and dry climate, thus accelerating the strength and frequency of drought. Climate change affects the change of agricultural climate resources and brings positive or negative effect to crops. Therefore, it is a key issue to tackle climate change in a scientific and reasonable way, take full advantage of agricultural climate resources and be benefit-tending and harm-avoiding in order to guarantee sustainable development of agriculture.