[农业]贺兰山论文：贺兰山典型森林类型凋落物层水文效应研究.doc

贺兰山论文：贺兰山典型森林类型凋落物层水文效应研究 【中文摘要】贺兰山处于我国温带草原区和荒漠区的过渡区域,是我国西北的著名山体之一,也是一个生态系统脆弱区,其自然环境的复杂性、生态系统的脆弱性在我国都有典型的代表性,被我国定为水源涵养林国家级自然保护区。因此,开展贺兰山典型植被水土保持功能的研究具有重要意义。结合国家林业公益性行业专项“陕西宁夏省区森林生态系统服务功能定位观测与评估技术”,以贺兰山4种典型自然森林类型(油松青海云杉混交林、油松山杨混交林、油松纯林和青海云杉纯林)为对象,对其森林凋落物层的水土保持功能进行了研究。并在大量的野外调查和室内试验的基础上,建立了凋落物持水性能的相关关系模型,并对贺兰山森林植被凋落物层的水源涵养功能进行了评价。结果表明:(1)通过对贺兰山不同植被类型临时样地凋落物层储量的调查和分析,发现不同植被类型的凋落物层储量存在差异,青海云杉纯林最高,达32.39t/hm~2,其后为油松云杉混交林和油松纯林,凋落物现存量分别达到26.6t/hm~2和25.21 t/hm~2,油松山杨混交林最低,仅为19.74t/hm~2。各植被类型凋落物的含水率最高为青海云杉纯林,达到89.72%,油松云杉混交林也达到83.15%,仅次于青海云杉纯林,油松纯林林地凋落物含水率最低,仅为73.95%。(2)凋落物的室内浸泡试验结果表明,凋落物持水量是随浸泡时间的延长而增大,在前2h内吸水速度最大,之后急剧下降,各森林类型间趋势基本一致,但不同植被类型间持水量相差较大。油松山杨混交林凋落物的饱和持水量最高,达到自身重量的1.84倍,其后依次为油松纯林、油松云杉混交林,分别为自身重量的1.53倍和1.51倍,青海云杉纯林最低,为1.44倍。(3)各森林植被类型林地凋落物的持水量和持水率都随着浸泡时间的增加按照对数方程增加;吸水速率呈现油松山杨混交林油松云杉混交林≥油松纯林青海云杉纯林,且各类型林分的凋落物吸水速率随浸泡时间的增长按幂函数方程下降。建立了各林型凋落物吸持水量与浸泡时间、吸水速率与浸泡时间相关关系模型。(4)有效拦蓄量林型间变化范围为10.7~ 15.73t/hm~2 ,油松山杨混交林最大,为15.73t/hm~2,油松纯林(14.05t/hm~2 )和油松云杉混交林(11.98t/hm~2 )次之,青海云杉纯林最小,仅为10.7 t/hm~2。 【英文摘要】Helan Mountain in the temperate grasslands of the transition area and the desert area, is a famous mountain in northwest China, one area is a fragile ecosystem, its natural environment, the complexity of the vulnerability of ecosystems are typical representative in China, Been designated as water conservation forest of National Nature Reserve. Therefore, the typical vegetation of Helan Mountain Soil and Water Conservation to carry out the research function is important.Forestry industry with the state public welfare projects, “Shaanxi and Ningxia provinces, autonomous regions Function of Forest Ecosystem Services Monitoring and Assessment Technology”to the Helan Mountains in 4 typical natural forest types (spruce pine forest, mixed oil Matsuyama Yang, pure pine Qinghai spruce forests and pure stands) as the object of its forest litter layer of soil and water conservation features were studied. And a large number of field investigation and laboratory tests, based on the establish