东北地区植被过渡带生态气候学研究

Eco-climatic Study on Vegetation Transition Zones in Northeast China

温度和水分是决定植被分布重要的能量和物质基础 ,其长时间尺度的变化和短时间尺度的波动是植被过渡带形成和分布的主要原因。从生态气候保证率出发 ,以桑斯威特 (C .W .Thonthwaite)温度效率指数 (PE)的90 %保证率为过渡带上边界和 10 %保证率为过渡带下边界 ,定量地划分了东北地区由南向北因温度差异形成的森林植被过渡带 ;以湿润指数 (Im)的 80 %保证率为过渡带上边界和 2 0 %保证率为过渡带下边界 ,定量地划分了由东向西因水分差异产生的森林、草甸草原和典型草原间的过渡带。

As the basis of energy and substance, temperature and water play very important role in distribution of vegetation zones. Their long term scale change and short term scale fluctuation are essential causes of formation and distribution of vegetation transition zone. By using 90% ratio of eco climatic factor′s assurance of Thornthwaite PE as upper limit and 10% as lower limit of vegetation transition zone, forest vegetation transition zones of Northeast China are quantitatively classified. And 80% ratio of eco climatic factor′s assurance of Thornthwaite I m as upper limit and 20% as lower limit of vegetation transition zone forest/meadow/ prairie vegetation transition zones are classified.