河北平原温度与降水变化及其对小麦玉米熟制的影响-作物专业毕业论文.docx

域三0℃积温4000-4500。C·d向北推移至青龙县南部,与此同时4500,-4900。C·d向北移动,×104km2,;高值区(>4900℃·d),%an2。保定北部积温达到4500"-" 4900℃·d,研究区域北部的廊坊地区≥0℃积温在时段II也达到4500,-一4900℃·d,表明时段Ⅱ廊坊及其以南地区均可满足冬小麦复种夏玉米中熟品种的热量要求。此外,邢台邯郸等地20℃积温在时段II超过4900℃·d,表明该地区满足冬小麦复种晚熟玉米品种的热量要求。
(6) 1,3~-、7~9 --,全年及7-9月降水相对稳定,3~5月降水变异较大。 3。5月适逢小麦拔节至抽穗期,此阶段为小麦的需水临界期,需要大量水分,河北平原3~,降水较少并且变异系数较高,降水耦合度低,这就需要大量的灌溉水。7-9月适逢夏玉米拔节至成熟期,,降水较多并且变异较小,降水吻合度高基本能满足夏玉米的生长需求。当前,河北平原最大的现实是严重缺水,已不宜推广水资源消耗较大的两熟制,根据最小因子定律,应适当减少冬小麦种植面积。
关键词:河北平原;气候变化;温水资源;种植制度
万方数据
Temperature and Precipitation Change and Its Impact on Wheat-Maize Planting
Regime in Hebei Plain
Master Candidate:Chen Sheng
Major:Crop
Supervisor:Du Xiong
ABSTRACT
Global climate es warming and scholars at home and abroad pay aRenfion to it. Temperature rises has changed the agricultural heat-water resource of the spatial distribution and make more far-reaching impact on the background of giobal wanning,studying on climate change and its impact on wheat-maize planting regime in
Hebei Plain Can take the initiative to respond to climate changes,utilize climatic resources
properly and optimize the planting regime of the on the 1 966_20 1 2 observation data from 1 1 meteorological stations in Hebei Plain,the research made analysis on the changes of the first and last day and the interval of them,with the daily
temperature above 0℃and 1 0℃stably,the change of the accumulated temperature and
precipitation in different space and also in different years and decades and the influence on
wheat- results are as follows:
(1)Annual mean temperature within the research time limit is 1 ℃.increasing rate iS ℃/1 0a and the annual and seasonal mean temperature present a obvious rising tendency in the and winter average temperature increase IS more than the summe