防护林网内玉米田生物量和生产力格局的研究

A STUDY ON THE PATTERNS OF BIOMASS AND PRODUCTIVITY OF THE CORN CROPLAND IN SHELTERBELT NETWORK

本文报道了松嫩平原防护林网内玉米(Zea mays)田的生物量和生物生产力的时空格局及其与生态、生理因子的关系。研究结果表明:林网东西两条主林带间不同位置玉米的生物量和生产力在生长季各时期均有显著差异。生物量在距西侧主林带5—10倍树高(H)处最高,距离为1树高处最低,25倍树高处亦较高。在大部分时间里生产力的水平格局为“N”形。两个峰分别为10H 和25H。南北两条副林带间的生物量和生产力无明显差异。林网内生物量和生产力的分布格局受林网内温、湿因子分布的制约,不同时期的限制因子不同。叶面积和同化速率对生产力格局也有重要影响。林网内玉米穗生物量明显高于无林地。本研究指出,应适当缩短主林带间距,并可在林带附近种植浅根、矮秆和耐荫性作物,以提高整个林网的生产力和经济效益。

The time and space patterns of the biomass and biological produ- ctivity of corn(Zea mays)cropland in the shelterbelt network in Song- -Nen plain and the relationship among the patterns,ecological and physiological factors in network were studied.Results showed that: The biomass and productivity in different position between the east and west belts had significient differences in each peroid in the gro- wing season.The maximum biomass occured in 5—10 multiples of tree height(H),minimum in IH,and the biomass was also high in 25H. The level distribution of the productivity was“N”shape in most time of the growing season,two peaks occured in 10H and 25H respecti- vely.The biomass and productivity between the south and north be- lts had no difference.The patterns of the biomass and productivity in shelterbely network were restricted by the distribution of tempe- rature and humidity in the network,and the restrict factor was di- fferent in different time.The leaf area and assimilate rate also had important effect on the pattern of productivity.The biomass of ear within network was higher than that in the open land.