闽东北鹫峰山天然黄山松林内降雨分配的研究

通过对闽东北鹫峰山雨期天然黄山松林内降雨分配情况进行观测研究,结果表明:在观测期间,总降雨量1622.12mm,穿透雨量、树干茎流量和林冠截留量分别为1194.19mm、15.16mm和412.77mm,分别占总降雨量的73.62%、0.93%和25.45%.随着降雨量的增大,树干茎流量和茎流率、穿透雨量和穿透率、林冠截留量都增大,而林冠截留率降低.穿透雨量和总降雨量之间的关系为线性相关关系;茎流量和降雨量之间的关系也为线性相关关系;林冠截留量和总降雨量之间的关系为幂函数相关关系.     

西藏色季拉山高山松林降雨再分配格局研究

对西藏色季拉山高山松林冠截留、树干茎流与大气降雨量之间的关系进行了研究。结果表明:观测期间总降水量达337.90 mm,其中林冠截留量为82.17 mm、截留率为24.32%、变化幅度为13.19%⁶8.72%,穿透雨量为215.76 mm、穿透率63.85%、变化幅度为1.67%68.72%,穿透雨量为215.76 mm、穿透率63.85%、变化幅度为1.67%¹3.57%,树干茎流量39.97 mm、茎流率11.83%、变化幅度为29.70%13.57%,树干茎流量39.97 mm、茎流率11.83%、变化幅度为29.70%⁷3.26%。林冠截留量、穿透降雨量和树干茎流量与林外降雨量之间的关系分别为幂函数、直线性和二次函数关系。降雨的发生与林冠截留的产生是同步的,但是穿透产生和茎流产生与降雨发生并不同步。穿透雨和树干茎流是降雨量达到一定程度才开始出现的,而且刚开始很小,随后逐渐增大。     

紫金山麻栎林降水分配格局研究

对紫金山栎林林冠截留、树干茎流与降水量之间的关系进行了研究。在观测的46场降水中,降水量达823.8 mm,林冠总截留量、树干茎流量和穿透雨量分别为207.95 mm、33.30 mm、582.55 mm,林冠截留率、树干茎流率和穿透率分别为25.24%、4.04%、70.71%。随着降水量的增大,林冠截留量、树干茎流量、穿透雨量及穿透率都有所增加,林冠截留率降低,树干茎流率在2～50 mm降水量级中逐渐增大,在>50 mm降水量级有所降低。林冠截留量与降水量之间呈幂函数关系,而树干茎流量、穿透雨与降水量之间呈线性相关。     

官司河流域马尾松林林冠截留降水特征研究

本文通过统计分析法对官司河流域的马尾松林林冠截留、林内穿透雨以及树干茎流进行了研究。结果表明：在该林分中林内穿透雨量和树干茎流量在降雨量达到一定值后开始出现,并随降雨量的增加而以增加,并呈现线性相关关系。林冠截留量随降雨量的增加,呈幕函数关系上升,最终趋于饱和,而林冠截留率则随降雨量的增加而减少。     

内蒙古大青山白茬子沟小流域典型森林植被的冠层降水再分配特征

利用生长季观测的降雨数据,分析了内蒙古大青山白茬子沟小流域白桦次生林和华北落叶松人工林林冠降雨截留、穿透雨及树干径流与降雨量的关系,以及降雨林冠截留过程的特征。结果表明:两种林分林冠截留量与降雨量的关系吻合对数回归模型;穿透雨量、树干径流量与降雨量均呈明显的一元线性关系,穿透雨量和树干径流量均随着降雨量的增加而增加。不同林分的林冠截留量、穿透雨量和树干径流量的月动态变化与总降水量的月变化基本一致;林内穿透雨率超过73%,冠层截留率9.81%~26.22%,树干径流0.72%~9.10%。     

流溪河小流域针阔混交林林冠降雨截留模型研究

以流溪河流域针阔混交林为研究对象,对林分样地进行降雨截留实测与模拟研究.结果表明:林内穿透雨量与降雨量呈线性相关;穿透系数与降雨量呈对数相关;林冠截留量与降雨量呈幂函数相关;截留率与降雨量呈对数相关.以降雨强度、穿透系数和树干茎流率数据为基础,进行了林冠截留量模型模拟,实测表明该模型能较准确地估算针阔混交林分的林冠截留量.     

天然次生林对降水的分配效应浅析

通过观测我国东北东部天然次生林对降水的分配效应,结果表明:降雨量在1.69～24.36 mm时,森林各水文分配效应总体表现为穿透雨量>地表径流量>树干茎流量>林冠截留量.随降雨量和降雨强度的增加,穿透雨量、地表径流量和树干茎流量随之增大.当降雨量较小(1.69～4.91 mm)时,穿透雨量、地表径流量和树干茎流量随降雨量的增加呈低速增加趋势;当降雨量较大(4.91～24.36 mm)时,其增加速度随降雨量的增加而加快.     

武夷山甜槠常绿阔叶林林分降水分量特征

2004年对武夷山甜槠林不同水文分量定位观测,探讨甜槠林森林水文与降水的关系 .结果表明:1)2004年共发生降水219次,年降水量1 767.4 mm,穿透水、茎流量和林冠截留量分别为1 304.9、245.0和217.5 mm;穿透率、茎流率和截留率分别为73.8%、 13.9%和12.3%;2)同次降水中,林内不同位置的穿透雨量差异显著,穿透水量与大气降水量之间存在明显的线性关系;3)随着胸径的增加,茎流量减小,形成茎流的时间推迟;4)当降水量<202.1 mm时,林冠截留量随着降水量的增加而增加;当降水量超过202.1 mm后,林冠截留量趋于定值52.5 mm.     

湖南省张家界马尾松林冠生态水文效应及其影响因素分析

对马尾松林的穿透雨、林冠截留和树干流的水文效应进行监测,并对其影响因素进行初步分析.结果表明:降雨主要集中在5-8月,期间穿透雨量、林冠截留量和树干流量分别占全年分配量的一半以上.穿透雨量、树干流量和林冠截留量与降雨量显著正相关,而穿透雨率和树干流率随着降雨强度的增加而升高,但截留率逐渐降低.马尾松林穿透雨量最大值出现在最大雨量级(≥90.0 mm)和3.0～4.0 mm·h-1雨强范围内; 但是截留率最大值出现在最小的雨量级(＜10.0 mm)和＜1.0 mm·h-1雨强范围内; 树干流率最大值出现在中等雨量(60.0～70.0 mm)和2.0～3.0 mm·h-1雨强范围内,显然降雨特征是影响马尾松林内雨的关键因子.林下穿透雨率存在明显的空间异质性,靠近树干的林冠内部穿透雨率高于林冠外部,而且空间异质性随着降雨量的增加而降低.马尾松树干流与胸径及冠层面积呈极显著正相关.     

基于修正的Gash模型模拟缙云山毛竹林降雨截留

为了验证修正的Gash模型对缙云山毛竹林林冠截留模拟的适用性,基于2009年4—7月的气象和林分特征资料以及实测的穿透雨和树干茎流等资料,分析缙云山毛竹林林外降雨、穿透雨和树干茎流特征,并应用修正的Gash模型对林冠截留量进行模拟,对比分析周降雨累计截留量和单次降雨截留量的模拟值和实测值,采用敏感性分析法分析模型参数对截留量的影响程度。结果表明:研究期间共29次降雨,总降雨量为531.1mm,平均降雨强度为2.11mm·h-1,大部分为低雨强、低雨量级、长历时的降雨;穿透雨量、茎流量和林冠截留量的实测值分别为463.2,6.5和61.4mm,模拟值分别为461.1,6.1和63.9mm,模拟的截留量约高出实测值4.07%,模型计算的周累积截留量和单次降雨截留量与实测值相比的相对标准差分别为5.02%和7.13%,模拟效果较好,模型适用于缙云山毛竹林;以林冠郁闭度(c)对模拟结果影响最大,其次为平均降雨强度()、林冠持水能力(S)和林冠平均蒸发速率(),树干茎流系数(Pt)和树干持水能力(St)这2个参数对林冠截留总量影响很小。     

川西亚高山原始云杉林内降雨分配研究

穿透雨、茎流和林冠截留在森林生态系统水文循环和水量平衡中占有极其重要的地位 (VanDijketal .,2 0 0 1) ,因而从生理学、生态学和水文学的观点来看 ,研究一定区域内植被与降雨之间的相关性具有重要的意义 (Aboaletal .,1999)。川西亚高山针叶林处于我国东南半壁湿润地区与西北半壁干旱地区的过渡地带上 ,且多分布于江河上游 ,在涵养水源、保持水土、稳定河川流量、维护生态平衡等方面具有重要的地位 ,被誉为庇护四川及长江流域的“绿色万里长城”(杨玉坡 ,1990 )。马雪华 (1987)对米亚罗地区亚高山冷杉林的林冠截留做了一些初步的观测 …     

Throughfall,stemflow and interception loss in a mixed white oak forest (Quercus serrata Thunb.)

Throughfall and stemflow measurements in a 60-year-old white oak stand (Quercus serrata Thunb.) were carried out during two periods totalling eleven months, from August to November 1993 and from May to November 1994, in order to clarify the rainfall partitioning of this forest. Troughs and spiral-type stemflow gauges connected to tipping bucket-gauges were used for throughfall and stemflow measurements. Seventy-five storms were analyzed individually. Coefficients of variation for throughfall and stemflow ranged between 5–25% and 20–70% respectively. Partitioning of net rainfall in throughfall and stemflow represent 72% and 10% of the gross rainfall respectively. Multiple regression analyses were carried out to determine the stemflow variability. In was determined that maximum rain intensity was highly correlated with stemflow and this variable explained a further 5.5% of the stemflow variation. Estimates of averaged lag time and drainage after rain cease for stemflow were 290 and 164 min, while estimates for throughfall were 60 and 104 min. respectively. The canopy saturation was estimated from continuous storms and showed a value of 0.6 mm. The trunk storage capacity was estimated at a value of 0.2 mm. The interception loss from the forest canopy was estimated in 18%. Interception loss was heighly correlated with rainfall characteristics such as duration and intensity.     

Characteristics of canopy interception and its simulation with a revised Gash model for a larch plantation in the Liupan Mountains,China

Canopy interception is a significant proportion of incident rainfall and evapotranspiration of forest ecosystems. Hence, identifying its magnitude is vital for studies of eco-hydrological processes and hydrological impact evaluation. In this study, throughfall, stemflow and interception were measured in a pure Larix principis-rupprechtii Mayr.(larch) plantation in the Liupan Mountains of northwestern China during the growing season(May–October) of 2015, and simulated using a revised Gash model. During the study period, the total precipitation was499.0 mm; corresponding total throughfall, stemflow and canopy interception were 410.3, 2.0 and 86.7 mm,accounting for 82.2, 0.4 and 17.4% of the total precipitation, respectively. With increasing rainfall, the canopy interception ratio of individual rainfall events decreased initially and then tended to stabilize. Within the study period, the simulated total canopy interception, throughfall and stemflow were 2.2 mm lower, 2.5 mm higher and0.3 mm lower than their measured values, with a relative error of 2.5, 0.6 and 15.0%, respectively. As quantified by the model, canopy interception loss(79%) mainly consisted of interception caused by canopy adsorption, while the proportions of additional interception and trunk interception were small. The revised Gash model was highly sensitive to the parameter of canopy storage capacity,followed by the parameters of canopy density and mean rainfall intensity, but less sensitive to the parameters of mean evaporation rate, trunk storage capacity, and stemflow ratio. The revised Gash model satisfactorily simulated the total canopy interception of the larch plantation within the growing season but was less accurate for some individual rainfall events, indicating that some flaws exist in the model structure. Further measures to improve the model's ability in simulating the interception of individual rainfall events were suggested.     

长白山北坡阔叶红松林林冠对降雨及其养分的影响

在2001年森林生长季(6-9月),通过测量降雨各分量,分析了中国吉林省长白山北坡红松阔叶林冠层对降水分配各分量的影响。结果表明:干流量(37.39 mm),透流量(326.02 mm)和截留量(105.67 mm),分别占同期降雨量(469.08 mm) 的7.97%、69.50%和22.53%。林冠对降雨的月份分配规律是:树干茎流率的月变化为七、八月份大于其它月份,穿透率从6-9月份有逐渐减少的趋势,而截留率的变化正好与穿透率相反,从19.43%增加到31.02%。林内降雨中的养分元素浓度发生显著变化,除Ca、Mg外,其它元素的浓度都有所增加。经分析得出,大气降雨中养分元素的浓度序列为:Ca> Mg> N> K> Fe > P> Cu > Mn;而穿透雨中养分元素的浓度序列为:K>N>Mg>Ca>P>Fe>Mn>Cu;在林冠淋溶中各养分元素的浓度序列为:Mn> P>K>Cu>Fe>N>Mg>Ca。图1表5参13。     

长宁竹海主要林分林冠降雨分配格局

对长宁竹海楠竹林、黄竹林、苦竹林、杉木林和栎林5种林分林冠降雨分配格局进行了对比。回归结果表明:穿透雨量和干流与林外降雨量呈线性关系,并都达到极显著水平(p-0.01)。在降雨量为1204.7 mm时,5种林分穿透雨的最小响应雨量分别为:斑苦竹(Pleioblastus amarus Kengf)林为3.0 mm,硬头黄竹(Bambusa rigida Keng et Kengf)林为1.0 mm、白栎(Quercus fabri Hance)林为0.9 mm、楠竹(Phyllostachy spubescen)林为0.8 mm、杉木(Cunninghamia lanceolata Hook)林为0.7 mm。干流量随树干胸径的增加而增大,两者关系可用Q=B0 B1D B2D2 B3D3进行描述。与其它的林种相比,竹林干流量远高于栎林和杉木林。苦竹林干流量达105.3 mm,干流率为8.74%,黄竹和楠竹干流量均为82.4 mm,干流率为6.84%,栎林分别为42.4 mm和3.49%,杉木林最小,仅为8.8 mm和0.73%。截留量和截留率从大至小的排序为:苦竹林为384.3 mm和31.9%,栎林355.5 mm和29.51%,黄竹280.7 mm和23.3%,楠竹274.1 mm和22.75%,杉木林254.8 mm和21.15%。     

珠江三角洲城市森林植被生态系统水质效应研究

2002—2003年对顺德大良大岭山常绿针阔混交林集水区水循环过程进行了定位监测,该林区年降水量为1628．9mm,5—9月份的降雨量占82．4％,穿透降水占降雨的85．01％,干流占3．17％,冠层截留占11．82％,冠层水文效应显著。工业区年降雨pH均值为5．27、酸雨频率67．8％;大良和龙江居民区年降雨pH均值分别为5．84、5．72,酸雨频率平均为27．1％;森林区大气降水的pH值6．31、酸雨频率为6．5％。森林区降水中Pb、Cd、Cl^-、NO3^-、SO4^2-的含量小于国家I类水标准,总P(TP)、Cu、Zn含量接近国家I类水标准。大气湿沉降化学物质经过林冠后,穿透雨的总P、K、Zn、Pb浓度分别增加了1、2、7、1倍,Al、Ca、Cu浓度减少了89．8％、40．7％、30．5％。土壤105cm深度渗透水PO4^3-、Cr^-、NO^3-、SO4^2-阴离子的总浓度相对15cm深减少33．5％;Cu、Zn、Pb、Cd浓度相对15cm深的渗透水分别减少了62．5％、64．5％、38．9％、84．6％;森林土壤的储虑机制对于输出环境的径流水质量有显著改善作用。     

Nutrient accessions to the forest floor in karri (Eucalyptus diversicolor F. Muell.) forests of varying age

Nutrient accessions to the forest floor in rainfall, throughfall and stemflow from the understorey and tree strata were measured in karri (Eucalyptus diversicolor F. Muell.) forest of south-west Western Australia. These data, for stands aged 2, 6, 9, and 40 years and for mature forest, were compared with annual accessions of nutrients in litterfall.

With increasing age of the stands, the concentration and amounts of Ca, K, Mg, Na and Cl in throughfall increased. The amounts of Mg, Na and Cl in stemflow from the overstorey were also greatest in the older stands. Although concentrations of nutrients in stemflow from the tree stratum were higher than from the understorey, the quantities of nutrients transported to the forest floor in stemflow from the understorey were greater because of its greater volume.

Rainfall is the major source of Na (64–91%) and Cl (51–79%) and it also contributes significantly to Mg (19–50%) accessions. Of the nutrient pathways between canopy and forest floor, litterfall accounts for the largest proportion of N (89–93%), Ca (80–87%) and P (67–79%) recycled in the karri forest. About equal amounts of K are transferred in litterfall, throughfall and stemflow with approximately 80% of stemflow K originating from the understorey strata.     

Interception loss, throughfall and stemflow chemistry in pine and oak forests in northeastern Mexico

Interception loss, gross precipitation, throughfall and stemflow solution chemistry beneath pine (Pinus pseudostrobus Lindl.), oak (Quercus sp.) and pine-oak natural forest canopies in northeastern Mexico were measured. Coefficients of variation for throughfall were 12% in pine and oak canopies and 17% in the mixed pine-oak canopy. The variability of stemflow averaged 66, 126 and 73% for pine, oak and the mixed pine-oak canopies, respectively. Linear regression analysis of net versus gross precipitation for the three canopies showed highly significant correlations (r = 0.974-0.984). Total precipitation during the experimental period was 974 mm and estimated interception loss was 19.2, 13.6 and 23% for the pine, oak and pine-oak canopies, respectively. Stemflow did not occur following rainfall events of less than 4 mm and, in all canopies, stemflow represented a minimal proportion of gross precipitation (0.60, 0.50 and 0.03% for pine, oak and pine-oak, respectively). Throughfall pH in pine (6.2), oak (6.3) and pine-oak (6.3) canopies was significantly more acidic than gross precipitation (6.6). Stemflow pH ranged from 3.7 (pine) to 6.0 (oak). The pine-oak canopy registered the highest throughfall and stemflow electrical conductivities, 104 and 188 microS cm(-1), respectively. Net nutrient leaching of K, Mg, Na, Fe, Mn and Zn was significantly higher from the pine-oak canopy than from the pure pine and oak canopies. Mean depositions of Ca and Cu in throughfall behaved similarly among the three types of canopies. A greater proportion of Zn in gross precipitation was absorbed by the oak canopy than by the pine and pine-oak canopies. Enrichment factors beneath the pine-oak canopy relative to gross precipitation varied from 1.2 to 3.2 for macro-nutrients (Ca, K, Mg and Na) and from 1.4 to 3.1 for micro-nutrients (Cu, Fe, Mn and Zn). Stemflow depositions of Ca, K, Mg and Cu were higher in the pine-oak canopy, whereas stemflow depositions of Na, Fe, Mn and Zn were higher in the pine canopy.