林网内作物光合作用生理生态过程特征

Physiological Process Characteristics of Crop Photosynthesis in Shelternets

通过测定林网网格内不同作物光合作用生理生态过程中主要指标,发现农田防护林网对农田上不同区域内作物的光合作用过程存在着不同程度的影响,林带的影响尺度主要在林带边缘农田上0～2H的区域内表现最为强烈。同时在网格内不同时间、不同方位、不同走向林带的影响范围有着明显的差异,这种差异主要是由于林带的存在,使林网内不同区域光辐射强度不同,且作物叶面积获得的光辐射总量发生了变化所致,引起作物生产力的不同。研究结果表明,农田防护林是农田生态系统中作物界面环境因子异质性形成的主要因素。由于不同配置方式所构成的这种带状网络树木群体引起了一定范围内作物生长发育过程中生理活动所依赖的环境因子的变化,这种变化对作物的生理生态过程产生了相应的影响。

The results show that shelternets has different influence on the photosynthesis of crops after observing the most index of physiological and ecological process characteristics of crop photosynthesis in shelternets. The strongest reaction occurs in the area of 0~2H around farmland margin. Furthermore,there is obvious difference of photosynthesis in different time, position and direction of belts, which is mainly due to the difference of density of photosynthetic active radiation received by crops in shelternets, and thus result in the difference of crop production. Consequently, shelternet is regarded as the primary reason that formed the environment heterogeneity in the interface of farmland ecosystem. The trees group in shleternets formed by different disposition caused the changes of environment factors tied to physiological activity of crops grew in shelternets, and this important changes influenced necessarily the physiological and ecological process of crop photosynthesis in shleternets.