【作者】 陈艳；

【导师】 贺康宁；

【作者基本信息】 北京林业大学 ， 水土保持与荒漠化防治， 2015， 硕士

【摘要】 森林与水的关系在森林水文的研究中愈显重要,尤其随着社会经济的不断发展,以牺牲环境为代价的发展造成的水污染以及水资源极度缺乏的情况越来越严重,森林与水的关系愈来愈引起人们的重视。黑泉水库作为第七水源,为青海省会西宁市提供60%的供水,保障了西宁以及附近的工业、农业生产和人民生活的水使用,而研究区域宝库河流域是黑泉水库的水源区,其作用重中之重。因此,对该区域水源涵养林体系的建设研究是当务之急。本研究选取了当地主要乔木树种青海云杉林、白桦林、沙棘林、青杨林、华北落叶松林、云杉落叶松混交林和云杉白桦混交林共7个林分作为研究对象,通过野外调查和室内实验相结合的方式,采用方差分析、相关分析和主成分分析对林冠截留过程水量的分配与养分元素含量的变化进行测量分析。依据不同植被对其不同的响应,比较筛选养分与水量调节功能最佳的适宜植被类型,为当地水源涵养林体系的建设提供了理论依据。研究结果如下：(1)7种林分的林冠截留能力的大小为：云杉落叶松混交林(43.18%)>云杉白桦混交林(40.94%)>落叶松林(37.8%)>白桦林(34.5%)>青海云杉林(34.06%)>青杨林(30.49%)>沙棘林(30.33%),针阔混交林或针叶林体现出对降雨有较强的截留作用。林冠截留量与降雨量之间呈明显的幂指数关系；截留率与降雨量之间呈现对数函数关系,例如青海云杉林截留量、截留率与降雨量之间的关系：y=0.7709x0.5583,R2=0.533,P<0.01;y=-13.36ln(x)+64.87,R2=0.5166,P<0.01.(2)树干流量大小顺序为青杨林(0.551mm)>青海云杉林(0.459mm)>沙棘林(0.375mm)>云杉白桦混交林(0.313mm)>云杉落叶松混交林(0.119mmm)白桦林(0.033mm)>落叶松林(0.026mm),主要影响因子为自身树干结构特征、降雨量降雨强度等因素,降雨量的月分配格局造成干流也出现月分配。树干流量与林外降雨量相关性均显著(P<0.01),树干流量与降雨量呈现一元线性关系,例如青海云杉树干流量与降雨量的关系：y=0.0478x-0.1544,R2=0.9692。流量与胸径呈现负相关,青海云杉林、华北落叶松林、白桦林、云杉白桦混交林、云杉落叶松混交林的回归分析方程主要为对数关系,青杨林和沙棘林的回归分析方程显示干流量与胸径呈幂指数关系。(3)林内降雨量均值大小顺序为：落叶松林>沙棘林>白桦林>云杉落叶松混交林>云杉林>云杉白桦混交林>青杨林,与植被的林冠构造、枝叶表面性质等有关。大部分水源涵养林林分的林内降雨量与降雨量相关性显著(P<0.01),之间呈现一元线性相关关系。青海云杉林内降雨量与大气降雨量的关系：y=0.779x-0.9824,R2=0.9895。(4)大气降水养分元素含量大小顺序为：Ca>N>K>S>Na>Mg>P>Zn>Fe >Mn>Cu;大部分元素含量呈现9月较高,6月较低；元素之间呈现一定的相关性,并与降雨量呈现线性关系；其中其主要贡献的有P、Ca、K、Mg、Mn, S、Zn,主要来自土壤矿石风化物和人类活动；养分元素输入量大小顺序为：Ca>K>N>S>Na >Mg>Mn>P>Zn>Fe>Cu。(5)7个林分林内降雨含量最高的元素是Ca元素,林冠对Mn、Zn元素呈现一定的吸附作用。不同林分养分元素的大致变化趋势一致,降雨通过林冠层后各元素含量呈现增长的趋势,针叶树种和针阔混交林的浓度、淋溶量以及输入量和养分贡献程度均相对较大；同一元素不同树种间具有差异性,同一树种不同元素间具有相关性,浓度与降雨量呈现幂指数关系,例如沙棘林内降雨Ca元素含量与降雨量的关系：y=84.801x-0.373,R2=0.8418,P<0.01。(6)不同树种树干流养分元素含量变化趋势大致相同,Ca元素含量最高；通过主成分分析,林地提供各化学元素贡献的树种顺序是落叶松林>青杨林>沙棘林>白桦林>云杉林,树干流养分输入量小于大气降水,Zn元素在沙棘林、青杨林和云杉林中表现出负淋溶现象。通过方差分析,同一元素不同树种间具有差异性；通过相关分析,同一树种不同元素间具有相关性,浓度与降雨量呈现线性关系,例如白桦林树干流Ca元素含量与大气降雨量之间的关系：y=-0.756x+64.826,R2=0.7724,P<0.01。更多还原

【Abstract】 The relationship between forest and water is more and more important in the study of forest hydrology. Especially with the development of society and economy, water pollution and extremly lack of water resources, which caused by these development at the cost of environment, has become more and more serious, which is constantly concerned by people of the importance of water and forest. Heiquan reservoir as a seventh water source provides 60% of the water supply for Xining City, the provincial capital of Qinghai,and plays an important role in the security of the industrial and agricultural water use as well as life and ecological use of water,so the study area,Baoku river basin,is more important as a water source of Heiquan reservoir.Therefore, the research on the systemconstruction of water conservation forest in this area should be a priority. As the object of study,seven main tree species were chosen including Picea crassifolia, Betula platyphylla Suk., Hippophae rhamnoides,Populus cathayana, Larix principis-rupprech Mayri, Picea crassifolia and Larix principis-rupprechi mixed forest, Picea crassifolia and Betula platyphylla mixed forest to measure and analyse the water distribution of canopy interception process and nutrient elements content with the method of field investigation and laboratory experiment combination and using variance analysis, correlation analysis and principal component analysis.Based on the different response of different vegetation types,the appropriate vegetation types of best quantity and quality regulating function of water are chosed through comparing,and provides a theoretical basis for the construction of the local water conservation forest system.The results are as follows.(1)The order of canopy interception capacity of 7 forest stands is:Picea crassifolia and Larix principis-rupprechi mixed forest (43.18%)> Picea crassifolia and Betula platyphylla mixed forest (40.94%)> Larix principis-rupprech Mayri. (37.8%)> Betula platyphylla Suk. (34.5%)> Picea crassifolia (30.49%)> Populus cathayana (30.49%)> Hippophae rhamnoides (30.33%), as we can see that coniferous and broad-leaved mixed forest and coniferous forest show a strong interception capacity. It shows an exponential function relation between canopy interception and precipitation,on the contrary, between interception rate and precipitation presents a logarithmic function relation. Such as Picea crassifolia,the relation is:y= 0.7709x0.5583, R2= 0.533, P<0.01; y=-13.361n(x)+64.87, R2= 0.5166, P<0.01.(2)The sequence of stemflow is:Populus cathayana (0.551mm)> Picea crassifolia (0.459mm)> Hippophae rhamnoides (0.375mm)> Picea crassifolia and Betula platyphylla mixed forest(0.313mm)> Picea crassifolia and Larix principis-rupprechi mixed forest (0.119mm)> Betula platyphylla Suk. (0.033mm)> Larix principis-rupprech Mayri. (0.026mm).The tree structure,recipitation,rainfall intensity and so on are becoming main influence factor for stemflow,besides,rainfall shows a monthly distribution pattern which give rise to a monthly distribution in stemflow.The correlation is significant between stemflow and precipitation (P< 0.01),but the stemflow may not like this. It shows a linear relationship between stemflow and rainfall,such as Picea crassifolia:y= 0.0478x-0.1544, R2= 0.9692.The stemflow has a negative correlation with DBH.Regression equation of Picea crassifolia, Betula platyphylla Suk., Larix principis-rupprech Mayri., Picea crassifolia and Be tula platyphylla mixed forest,Picea crassifolia and Larix principis-rupprechi mixed forest is logarithmic relationship between DHB and stemflow,but exponent relation is showed in Populus cathayana and Hippophae rhamnoides.(3) The sequence of mean throughfall is:Larix principis-rupprech Mayri.> Hippophae rhamnoides> Betula platyphylla Suk.> Picea crassifolia and Larix principis-rupprechi mixed forest> Picea crassifolia> Picea crassifolia and Betula platyphylla mixed forest> Populus cathayana,and this caused by canopy structure and surface properties of branches and leaves.Most water conservation forests show a significant linear correlation between throughfall and rainfall (P< 0.01),for instant, Picea crassifolia is:y= 0.779x-0.9824, R2=0.9895.(4)The sequence of the content of nutrient elements in atmospheric precipitation is:Ca>N>K>S > Na> Mg> P> Zn> Fe> Mn> Cu,and most of the elements content show higher in September, lower in June.There is a linear relationship correlation between elements content and rainfall.P, Ca, K, Mg, Mn, S, Zn contribute most which mainly come from weathered material of soil and mineral as well as human activities.The sequence of chemical element input is:Ca>K>N>S>Na >Mg>Mn>P>Zn>Fe>Cu.(5)Throughfall has the highest content of element Ca in 7 forest stand and canopy shows a adsorption of element Mn and Zn.7 different stands has the same variation trend and chemical element contents increase through canopy.It is considered relatively large in concentration,leaching amount,inputs and contribution of nutrient elements of coniferous trees and coniferous and broad-leaved mixed forest.Same elements have differences among different species,but correlation shows in different elements of the same tree species.There is also exponential relationship between concentration and througfall.For exsample, Hippophae rhamnoides is:y= 84.801x-0.373,R2= 0.8418,P<0.01.(6)Changes in the content of nutrient elements of different tree species’s stemflow have the same trend which also get the highest concent of element Ca. Through principal component analysis,the sequence of nutrient elements supply is:Larix principis-rupprech Mayri.> Populus cathayana> Hippophae rhamnoides> Betula platyphylla Suk.> Picea crassifolia.Nutrient input is less than precipitation and Zn shows a negative leaching in Hippophae rhamnoides, Populus cathayana and Picea crassifolia.Through variance analysis differences show in different trees while it has correlation in different elements by correlation analysis.We can see a negative linear relationship between concentration and precipitation,such as content of element Ca in Betula platyphylla Suk.:y=-0.756x+ 64.826,R2=0.7724,P<0.01.更多还原