气候变化对东北地区玉米生产的影响

利用气象观测数据、玉米产量及面积资料,分析了东北地区气候变化事实及对玉米生产的影响。研究表明:1971年以来,东北地区≥10℃积温增加了262.8℃,≥10℃积温带(以2700℃为例)平原区向北推进了约200～300km左右,向东扩展50～150km。1991年开始玉米生长季(4～9月)降水量持续减少,年平均水分亏缺量达391.5mm,湿润区缩小,有变干趋势。初霜日推后7～9天,无霜期延长了14～21天,霜冻灾害几率降低。20世纪90年代后,玉米延迟型冷害进入低发期。随着热量资源的增加,玉米可种植区范围不断扩大,种植北界北移东扩,玉米适播起始时间提前。玉米总产、播种面积增加趋势分别为967万t/10a、72万hm2/10a。未来40年东北地区玉米产量以减产为主,与过去30年(1961～1990年)相比平均减产9.5%左右。调整玉米种植布局和品种搭配,依靠水利工程和推广旱作农业技术,选种耐旱、抗病、抗逆性强的玉米品种,是实现东北玉米生产可持续发展的主要措施。

Effect of climate change on maize production in Northeast China

This paper analyzed the facts of climate change and its effects on the maize production in Northeast China according to the meteorological,maize yield and planting area data.The results are as follows.The heat resources in this region have been increasing continually since 1971.The accumulated temperature over 10℃ has increased by 262.8℃ averaged for the whole region.The plain area with accumulated temperature(≥10℃) higher than 2700℃ has extended northward 200-300 km,and eastward 50-150 km respectively.The precipitation in growing period(from April to September) during 1981-1990 had an increasing trend,but has been decreasing continually since 1991.Annual average water deficiency amounts to 391.5 mm.Humid area is decreasing and the whole region has a drying trend.The early frost date(the date with the lowest temperature ≤0℃) has postponed 7-9 days,and the frostless period has prolonged 14-21 days,so the probability of frost disaster occurrence is reduced.The period with high probability of lingering low temperature disaster on maize was observed in the 1960s and 1970s,and the period with low probability started in the 1990s.Heilongjiang Province had a high probability of frost disasters.With the heat resources increasing continually,adaptive area of maize planting is growing,with its north boundary extending northward and eastward,so the adaptive seeding date comes earlier.With steady increase of maize planting area and yield,the total yield and total planting area will increase by 9,670,000 t and 720,000 ha per decade respectively. Although climate change has supplied more heat resources for maize production in Northeast China,it is enhancing drought.So,we should adjust maize distribution and varieties.Additionally,using irrigation engineering and dry-farming technology widely,and selecting varieties with disease-resistance,drought-endurance and strong stress-resistance are the important measures to realize sustainable development of maize production in Northeast China.