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通过对重庆石漠化区2种植物群落凋落物层和土壤层的持水性能进行研究,结果表明:马尾松群落的蓄积量高于樟树群落,蓄积量高达48.3 t/hm2,不同分解层次的蓄积量,因植物群落类型不同而有别,测定结果显示针叶林的凋落物的蓄积量、鲜质量、干质量明显高于阔叶林;在两种群落中同种凋落物的不同分解层次的最大持水量、持水率,均是半分解层高于未分解层,马尾松群落持水总量高于樟树群落,达71.5 t/hm2,相应的持水深度也是马尾松群落高于樟树群落;马尾松群落凋落物的吸水量明显高于樟树群落,且每一种凋落物的半分解层的吸水量均大于未分解层,在持水过程中,两种凋落物呈现相同的变化趋势,在前4 h内吸水速率降低幅度大,4 h后吸水速度减缓,20 h后趋向于零.凋落物吸水量和浸水时间之间存在对数关系(y=aln(x)+b),凋落物吸水速率与浸水时间的关系按照反函数方程变化(y=a+bx-1);马尾松群落的总拦蓄量(98.18 t/hm2)大于樟树群落的总拦蓄量(59.26 t/hm2);马尾松群落可截留9.818 mm的林内降雨,樟树群落可以截留5.925 mm的林内降雨.且不同分解层次上也表现为半分解层的有效拦蓄量大于未分解层.表层土壤的持水性能也和凋落物层的持水性能呈现相同的规律,也表现为马尾松林高于樟树林.
The results showed that the stock volume of Pinus massoniana community was higher than that of camphor tree community, and the stock volume was as high as 48.3 t / hm2. The biomass of the litter layer and soil layer of two plant communities in rocky desertification area of Chongqing was up to 48.3 t / The results showed that the stock volume, fresh weight and dry weight of litter in coniferous forest were significantly higher than those in broad-leaved forest. In different decomposition levels of the same litter in the two communities, The maximum water holding capacity and water holding capacity were both higher than that of undecomposed layer, and the total water holding capacity of masson pine community was higher than that of camphor tree community, reaching 71.5 t / hm2. The corresponding water holding depth was also higher than that of camphor tree The water absorption of litter in the Pinus massoniana community was significantly higher than that of the camphor tree, and the water absorption of the semi-decomposed layer of each litter was larger than that of the undivided layer. During the water holding process, the litter showed the same trend , The rate of water absorption decreased greatly in the first 4 h, the rate of water absorption slowed down after 4 h, and tended to be zero after 20 h. There was a logarithmic relationship between water absorption of litter and water immersion time (y = aln (x) + b) The relationship between litter water absorption rate and water immersion time follows the inverse function (Y = a + bx-1). The total mass of the masson pine community (98.18 t / hm2) was larger than that of the camphor community (59.26 t / hm2) The community can intercept rainfall of 5.925 mm in the forest, and the effective interception capacity of the semi-decomposed layer is larger than that of the undecomposed layer at different decomposition levels. The water holding capacity of the surface soil also shows the same rule as the water-holding capacity of the litter layer. The performance of Pinus massoniana forest than camphor.