西双版纳热带人工雨林生物量及净第一性生产力的研究

通过标准木法和收获法研究分析了西双版纳热带人工模拟雨林的生物量及净第一性生产力.结果表明,林分总生物量约为390.4t·hm^-2,其中乔木层生物量达362.5t·hm^-2,占总生物量的92.8%,灌木层生物量为19.3t·hm^-2,占4.9%,层间植物(包括附生植物)的生物量为3.6t·hm^-2,草本层生物量为5.0t·hm^-2.分别占1.3%和0.9%.林分净第一性生产力为2227.3g·m^-2.年^-1,其中乔木层的净生产力为1553.5g·m^-2.年^-1,占整个林分净生产力的69.7%,灌木层、草本层及层间植物分别仅占26.9%、2.4%和1.0%.其器官分配比例以茎最高,达42.0%;其次为叶,占30.2%;枝仅占13.5%.叶面积指数为7.061.同时建立了林分优势种及乔木层各器官生物量的优化回归模型.

Effects of combinded application of organic manure and chemical fertilizers on photosynthetic characteristics of rice flag leaves

The effects of different nutrient inputs on photosynthesis and physiologic features in the flag leaves of rice were studied and compared. The results showed that photosynthesis rate (P\-n), chlorophll(chl) content and leaves area duration(LAD) were different under different nutrient treatments. Combinded application of chemical fertilizers and organic manure, especially barn yard manure, not only increase P\-n, delay discomposition of (chl) in the flag leaves, but also prolong duration of photosynthetic function and light interception in late stages of rice growth. As a result, they bring increase in grain weight and grain yield. In addition, combinded application of organic manure and chemical fertilizers resulted in high P\-n of rice leaves, even in high light intensitivity and high temperature at noontime.