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不同密度华北落叶松人工林径阶结构及水土保持功能的研究

标题: 不同密度华北落叶松人工林径阶结构及水土保持功能的研究
英文标题: Study on the Diameter Structure and Soil and Water Conservation on Larix Principis-rupprechtii Plantation of Different Density
作者: 张宇
出版时间: 2010-01-01
所在大学: 河北农业大学
关键词: 林分密度,华北落叶松,林分结构,水土保持功能
英文关键词: Density of stocking,Larch,Stand structure,Soil and Water Conservation
论文级别: 硕士
学位: 学位论文
导师: 滕起和%谷建才
专业: 森林经理学
提交时间: 2010
摘要: 华北落叶松(larix principis-rupprechtii Mayr.)是塞罕坝机械林场分布范围最广蓄积量积累最大的林分树种,近年来,塞罕坝机械林场在上级领导和各部门的关怀和支持下,取得了较高的经济和社会效益,旅游业也日趋旺盛.本文以塞罕坝机械林场立地条件基本一致的28年生华北落叶松人工纯林为研究对象,采用标准地调查法,对不同密度(分别为600、850、1100、1350、1600株·hm-2)下的华北落叶松林的径阶结构及水土保持功能进行了研究,得出主要结论如下:(1)利用径阶株树分布图及三参数Weibull函数来描述不同密度华北落叶松人工林林分的直径分布情况,经拟合检验,当密度为850株hm-2时林分直径近似Weibull分布效果.(2)在密度为600株·hm-2和850株·hm-2时,草本的高度和盖度到达最大值,分别为35.8cm和61.1%.草本物种丰富度在林分密度1350株·hm-2的情况达到最大值29种.在林分密度为1600株·hm-2的情况下,灌木物种数达到最高值6种.在林分密度1350株·hm-2的情况下,草本物种的多样性指数H、Pielou均匀度指数Jsw、多样性指数D均达到最大值,分别为2.9290、0.8830、0.9313.林分密度1600株·hm-2的情况下,灌木物种的多样性指数H、多样性指数、Pielou均匀度指数Jsi均达到最大值,分别为1.7201、0.8104、0.9725.(3)枯落物的贮存量与密度呈现出正相关关系,即随着密度的增加枯落物的贮存量也在不断增加.不同林分密度下枯落物未分解层和半分解层的吸水速率变化趋势是相同的,不同层次的枯落物吸水速率与其浸泡时间关系之间存在着显著的幂函数相关关系,拟合模型为幂曲线模型是V=a*Tb吸水速率吸水速率=a*浸泡时间b(a、b为指数).枯落物层的截留量的大小与枯落物的数量、质量、降水特征值以及自身湿润度和干旱速率密切相关.降水时间长、强度大,枯落物所截留的水量可以达到饱和,如果降雨过程继续则会降低截留率.(4)土壤容重随密度的增加呈现先增加后下降的趋势,不同密度下土壤容重大小关系为1100>850>1350>1600>600株·hm-2,毛管孔隙度、总孔隙度以及非毛管孔隙度随密度的变化趋势是850>1350>1100>600>1600株·hm-2,当华北落叶松林地密度为850株·hm-2时,毛管孔隙度、总孔隙度以及非毛管孔隙度最大为63.93%.壤的毛管持水量、最大持水量、田间持水量随密度的变化趋势是1100>1350>1600>850>600株·hm-2.对于不同密度下的华北落叶松林地,其入渗率为850>600>1100>1350>1600株·hm-2,对于28年生的落叶松密度保留在850株·hm-2时,其水土保持功能较好.从不同密度下土壤化学性质来看,当密度为1100株·hm-2时,土壤PH值及各养分情况较好.
英文摘要: Larch (larix principis-rupprechtii Mayr.) is the broadest and the most forest growing stock species accumulated in Saihanba mechanical tree farm. In recent years, the Saihanba mechanical tree farm in the higher authority leadership and under various departments' concern and support, has obtained high economy and the social efficiency, and the tourism is also exuberant day by day.This article lives the larch artificial pure crop take the Saihanba mechanical tree farm condition of local growth basic consistent 28 years as the object of study, uses the type place survey procedure, to the different density (respectively was 600,850,1100,1350, 1600·hm"2) under North China fallen leaf pinery stand structure and the soil and water Conservation has conducted the research,The main conclusions are as follows:(1) using the diameter step tree distribution map and the three-parameter Weibull function to describe the different density of larch plantation diameter distribution, by fitting test, when the density was 850·hm-2 old stand approximate diameter Weibull distribution results.(2) when the density is 600 hm"2 and 850 hm-2, the herb arrives at the maximum value highly with the degree of cover, respectively is 35.8cm and 61.1%. Herb species richness in forest density 1350·hm"2, reaches a maximum of 29 species. In the density of stocking is in 1600 hm-2 situations, the bush species number achieves the maximum 6 kinds. In the density of stocking 1350 hm-2 situations, herbaceous species' multiple index H, Pielou uniformity index Jsw, the multiple index D maximizing, respectively is 2.9290, 0.8830,0.9313. In the density of stocking 1600 hm"2 situations, bush species' multiple index H, the multiple indices, Pielou the uniformity index Jsi maximizing, respectively is 1.7201,0.8104,0.9725.(3) the storage of litter and density showed a positive correlation, which increases with the density of the storage of litter also increased. Under different stand density of litter layer and the semi-decomposition does not decompose water absorption rate in different layers is the same. the different level withers and falls the absorbing water speed to have the remarkable power function correlational dependence with its immersion time relationship, the fitting model for the power curve model is the absorbing water speed (a, b is index).Litter of interception by litter size and the quantity, quality, characteristic values of precipitation and drought, and its moisture is closely related to rate. Precipitation in a long time, intensity, litter interception of water by up to saturation, if the rainfall continues will be reduce the rejection rate.(4) The soil bulk density with the density increased first and then decreased, under the different density the soil bulk specific gravity size relations are 1100>850>1350>1600>600 hm-2, capillary porosity, total porosity and the non-capillary porosity with density, the trend is 850> 1350> 110O> 600> 1600 hm-2, when the larch forest density of 850·hm-2, the capillary porosity, total porosity and non-capillary porosity maximum of 63.93%. The soil capillary tube water capacity, the biggest water capacity, the field capacity along with the density change tendency are 1100>1350>1600>850>600 hm-2.Regarding the different density's under prince rupprecht larch forest land, its infiltration rate is 850> 600> 1100> 1350> 1600·hm-2, for the 30-year old larch density retained in the 850·hm-2 its soil and water conservation function better.From different densities of soil chemical properties, when the density is 1100·hm-2, the PH value of soil nutrients and the situation is better.