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1981~2006年锦州大豆产量与水分条件关系分析 被引量:6
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作者 刘景利 许振柱 +4 位作者 史奎桥 张丽华 杨扬 梁涛 张兵兵 《安徽农业科学》 CAS 北大核心 2009年第36期18050-18052,18085,共4页
[目的]分析1981~2006年大豆产量与水分条件的关系。[方法]采用SPSS10.0统计软件进行相关、一元及多元回归分析,当P<0.05时认为回归分析显著。[结果]近20年来,大豆生育期累计日照时数的年际波动较大,变异系数为12.0%,但0℃以上年积... [目的]分析1981~2006年大豆产量与水分条件的关系。[方法]采用SPSS10.0统计软件进行相关、一元及多元回归分析,当P<0.05时认为回归分析显著。[结果]近20年来,大豆生育期累计日照时数的年际波动较大,变异系数为12.0%,但0℃以上年积温呈显著增加趋势,其年际波动较小,变异系数为5.6%;日照时数和积温与大豆产量无明显相关性;降水量与生物量呈较强的显著正线性相关,收获指数与生育期呈负相关;全生育期、三叶期、出苗期、结荚期、鼓粒期和分枝期的土壤有效水含量对大豆产量的影响依次减小,而开花期和成熟期的土壤有效水含量对大豆产量无显著影响。[结论]该研究阐明了大豆产量波动规律及其气候区驱动机制,为在干旱缺水条件下实现大豆的稳产高产奠定了理论基础,为大豆田间管理提供了技术支持。 展开更多
关键词 年降水量波动 大豆 降水变化 土壤有效水分 土壤干旱 产量
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Water level changes in Polish lakes during 1976–2010
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作者 Dariusz WRZESI?SKI Mariusz PTAK 《Journal of Geographical Sciences》 SCIE CSCD 2016年第1期83-101,共19页
The paper presents the analysis of tendencies in water level changes in 32 lakes in Poland during 1976–2010.Series of monthly,seasonal,and annual precipitation and air temperature for 9 meteorological stations were a... The paper presents the analysis of tendencies in water level changes in 32 lakes in Poland during 1976–2010.Series of monthly,seasonal,and annual precipitation and air temperature for 9 meteorological stations were also studied.The trend analysis for all of the studied series of water levels in lakes showed high spatial and temporal variability.Series of annual water levels in the case of 6 lakes showed statistically significant increasing tendencies,and in 7 lakes,significant decreasing trends.Series of annual amplitudes in the majority of lakes(22) showed a decreasing trend,but they were statistically significant only in three cases.The tendencies for air temperature fluctuations are more statistically significant than precipitation.The key role in determining water level changes is played by local factors,particularly including human economic activity,obscuring the effect of natural factors on water level changes.The paper describes cases of changes in water levels in lakes under anthropopressure related to among others: agricultural irrigations,hydropower infrastructure,water transfers,navigation,or mining. 展开更多
关键词 lake-level trends lake-level regime Mann-Kandell Test climate change human activity
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