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1.
覆被变化引起的径流响应研究不仅是流域水文学的热点之一,在九寨沟更是与流域的水景观核心遗产价值保护紧密相关,因此九寨沟流域水资源的研究是迫切需要关注的问题。以SWAT模型模拟为基本研究手段,对九寨沟流域2009—2017年森林覆被变化下的流域水文做定量研究,探究了九寨沟流域对森林覆被变化的响应机理。结果表明：(1)模型率定期的决定参数R2和纳什效率系数Ens均为0.83,验证期的R2和Ens均为0.7,说明SWAT模型对九寨沟流域径流量模拟具有较高的适用性。(2) 2016年九寨沟流域内森林覆被面积较2004年有增加的趋势,其中针叶林面积增加明显(增加了10.56 km2),而阔叶林面积有所减少(减少了2.57 km2)。(3)相比2004年,2016年的森林覆被下的9年内年均径流量增加0.13 m3/s。年际变化中显示阔叶林的调蓄能力强于针叶林,而在年内变化中针叶林有更好的调洪补枯能力。(4)在气象条件相同的前提下,2016年月径流相... 相似文献
2.
《国际水土保持研究(英文)》2021,9(4):605-619
Headwater streams play a major role for provision of ecosystem services, e.g. drinking water. We investigated a high-altitude headwater catchment of the Kharaa River (including 41 1st-order rivers) to understand the impact of land cover (especially forest cover), environment and human usage on runoff, chemical water quality and macroinvertebrate fauna in a river basin under discontinuous permafrost conditions in an arid, sparsely populated region of Mongolia. To verify our hypotheses that different landuses and environmental impacts in permafrost headwaters influence water quality, we investigated 105 sampling sites, 37 of them at intermittent stream sections without water flow. Discharge was positively impacted by land cover types steppe, grassland and forest and negatively by shrubland, forest burnt by wild fires (indicating a reduction of permafrost) and slope. Water quality was affected by altitude, longitude and latitude, shrub growth and water temperature. Shannon diversity of macroinvertebrates was driven by water temperature, iron content of the water, flow velocity, and subbasin size (adjusted R2 = 0.54). Sample plots clustered in three groups that differed in water chemistry, macroinvertebrate diversity, species composition and bio-indicators. Our study confirms that steppes and grasslands have a higher contribution to runoff than forests, forest cover has a positive impact on water quality, and diversity of macroinvertebrates is higher in sites with less nutrients and pollutants. The excellent ecological status of the upper reaches of the Kharaa is severely threatened by forest fires and human-induced climate change and urgently needs to be conserved. 相似文献
3.
辽西低山丘陵区针叶林与阔叶林枯落物持水性对比 总被引：1，自引：0，他引：1
为对比分析辽西低山丘陵区针叶林与阔叶林枯落物的持水性差异,为辽西森林植被恢复提供科学依据和技术支撑,选取3个针叶林(红松林、油松林、兴安落叶松林)和3个阔叶林(榆树林、山杨林、紫椴林)下的枯落物作为研究对象,采用野外现场采样与室内浸水相结合的方法对枯落物的持水特性进行测定.结果表明:针叶林平均蓄积量大于阔叶林,其中针叶林蓄积量在14.65 ～ 17.75 t/hm2,阔叶林在8.44 ～ 16.92 t/hm2;针叶林枯落物平均厚度(2.79 cm)大于阔叶林(2.44 cm);针叶林最大持水率在148.88％ ～ 173.19％,阔叶林在145.42％ ～156.91％;针叶林有效拦蓄水量为19.47～25.59 t/hm2,阔叶林有效拦蓄水量为10.56～ 22.04 t/hm2,表现为针叶林下枯落物的拦蓄能力更强;针叶林半分解层拦蓄水量显著大于未分解层,阔叶林未分解层拦蓄水量大于半分解层;阔叶林未分解层吸水速率大于针叶林. 相似文献
4.
Haijin Zheng Zhao Liu Jichao Zuo Lingyun Wang Xiaofei Nie 《Eurasian Soil Science》2017,50(12):1506-1514
Soil nitrogen (N) loss related to surface flow and subsurface flow (including interflow and groundwater flow) from slope lands is a global issue. A lysimetric experiment with three types of land cover (grass cover, GC; litter cover, LC; and bare land, BL) were carried out on a red soil slope land in southeast China. Total Nitrogen (TN) loss through surface flow, interflow and groundwater flow was observed under 28 natural precipitation events from 2015 to 2016. TN concentrations from subsurface flow on BL and LC plots were, on average, 2.7–8.2 and 1.5–4.4 times greater than TN concentrations from surface flow, respectively; the average concentration of TN from subsurface flow on GC was about 36–56% of that recorded from surface flow. Surface flow, interflow and groundwater flow contributed 0–15, 2–9 and 76–96%, respectively, of loss load of TN. Compared with BL, GC and LC intercepted 83–86% of TN loss through surface runoff; GC intercepted 95% of TN loss through subsurface flow while TN loss through subsurface flow on LC is 2.3 times larger than that on BL. In conclusion, subsurface flow especially groundwater flow is the dominant hydrological rout for N loss that is usually underestimated. Grass cover has the high retention of N runoff loss while litter mulch will increase N leaching loss. These findings provide scientific support to control N runoff loss from the red soil slope lands by using suitable vegetation cover and mulching techniques. 相似文献
5.
密云水库土门西沟流域非点源污染负荷估算 总被引：2，自引：1，他引：2
密云水库水质影响北京市地表饮用水源质量,非点源污染成为密云水库水质下降的主要原因。为了满足水资源管理规划,在密云水库土门西沟小流域内根据不同的水土保持措施选择6个径流小区,主要有：板栗林、油松林、刺槐林、混交林、灌木林、梯田,于2007年对小区地表径流进行水质水量的监测。运用RUSLE公式和SCS法估算流域内不同水土保持措施的非点源污染负荷,利用ArcGIS工具绘制了土壤侵蚀量空间分布图。结果表明：土门西沟小流域非点源污染物主要来源于土壤侵蚀,泥沙中的吸附态是非点源污染物存在的主要形式;其次土门西沟小流域不同水土保持措施单位面积的污染负荷输出由大到小排列顺序为,经济林＞阔叶林＞灌木林＞针叶林＞混交林＞梯田。研究结果表明减少经济林来增加混交林用地面积,提高水源林的覆盖率,梯田可以维持现有的用地状况,禁止陡坡栽种农作物,坡脚和沟道农地采取梯田的耕种方式,以此来达到控制非点源污染的目的。跟以往研究得出的结论相反,梯田非点源污染负荷比林地小,主要是因为梯田相对坡耕地大大增加了地表入渗量,此外是因为梯田施用有机肥料,减少非点源污染。 相似文献
6.
Armando Molina Gerard Govers Veerle Vanacker Jean Poesen Edwin Zeelmaekers Felipe Cisneros 《CATENA》2007
Tropical mountain regions are affected by rapid land use/-cover change, which may threaten their (eco-)hydrological functions. Although there is a growing interest in evaluating the effect of land use/-cover change on mountain hydrology, quantitative assessments of the impact of land use/-cover on hydrological processes are hampered by the lack of field measurements characterizing runoff generation processes. In this paper, we present results from field experiments of rainfall runoff mechanisms in the southern Ecuadorian Andes. A rainfall simulator was used to quantify the hydrological response of distinct land use/-cover types to intense rainfall (about 40 mm/h). The rainfall runoff experiments indicate that degraded and abandoned land generate surface runoff within a few minutes after the start of the rainfall event. These lands have a very rapid and sharp hillslope hydrological response, as Hortonian overland flow is the dominant runoff generation mechanism. In contrast, surface runoff on arable and rangelands is rare, as their soils are characterized by a high infiltration capacity (i.e. > 29 mm/h). Our experiments provide evidence that runoff generation in degraded Andean ecosystems is mainly controlled by the surface vegetation cover and land management. When reducing the surface vegetation cover, the soil is increasingly affected by rapid hillslope runoff as the presence of large amounts of smectites in the outcropping soft rocks makes the material very prone to sealing and crusting, thereby enhancing runoff generation. 相似文献
7.
Seasonal variability of runoff and soil loss on forest road backslopes under simulated rainfall 总被引：1，自引：0，他引：1
Runoff and soil loss from forest road backslopes is a serious problem in Mediterranean areas. Surface runoff and sediment production on backslopes of forest roads in Los Alcornocales Natural Park (southern Spain) has been studied in this paper using a simple portable rainfall simulator at an intensity of 90 mm h− 1. One hundred rainfall simulations were performed on bare and vegetated road backslopes during summer and winter in order to study seasonal differences. Runoff coefficients and soil loss rates were lower on the vegetated plots than on the bare ones. Runoff coefficients increased 1.7 (bare backslopes) and 3.1 times (vegetated backslopes) from summer to winter. Preserving the vegetation cover over 20% is recommended for keeping soil loss rates under low levels, especially during winter. 相似文献
8.
The impact of vegetative cover type on runoff and soil erosion under different land uses 总被引：2，自引：0，他引：2
The effects of different vegetation types on runoff generation and soil erosion were investigated. The study was conducted at the Southern part of West Bank, about 10 Km north-west of Hebron city, during 2005, 2006 and 2007. Five treatments were implemented; forests planted with P. halepensis (F), natural vegetation dominated by S. spinosum (W.S), natural vegetation where S. spinosum was removed (W/o.S), cultivated land (C), and deforestation (Df). Three types of data were estimated in each plot: runoff after each rainfall event, sedimentation at the end of the rainy season, and chemical and physical soil properties. The obtained results indicate that there are significant and important differences in runoff generation and sediment production with respect to the different types of vegetative cover. Forest and natural vegetation dominated by S. spinosum treatments exhibited the lowest amounts of runoff, with averages of 2.02 and 1.08 mm, respectively, in comparison to other treatments. The removal of S. spinosum significantly increased the total amount of runoff and sedimentation compared to the forest and S. spinosum treatments. In addition, runoff significantly increased (4.03 mm) for the Df treatment compared to that of the forest site. The greatest amount of sedimentation was observed in cultivated land and with deforestation. 相似文献
9.
百喜草覆盖和敷盖对中国南方红壤坡地径流和产沙的影响 总被引：3，自引：0，他引：3
Rainfall,runoff (surface runoff,interflow and groundwater runoff) and soil loss from 5 m × 15 m plots were recorded for 5 years (2001-2005) in an experiment with three treatments (cover,mulch and bare ground) on sloping red soil in southern China.Surface runoff and erosion from the Bahia grass (Paspalum notatum Flugge) cover plot (A) and mulch plot (B) during the 5 years were low,despite the occurrence of potentially erosive rains.In contrast,the bare plot (C) had both the highest surface runoff coefficient and the highest sediment yield.There were significant differences in interflow and surface runoff and no significant difference in groundwater runoff among plots.The runoff coefficients and duration of interflow and groundwater runoff were in the order plot B > plot A > plot C.Effects of Bahia grass cover were excellent,indicating that the use of Bahia grass cover can be a simple and feasible practice for soil and water conservation on sloping red soil in the region. 相似文献
10.
11.
为给漓江流域红壤侵蚀区植被恢复和重建提供科学理论依据,研究漓江上游流域红壤侵蚀区主要植被类型群落内小气候环境因子的差异,采用“以空间导时间”的方法分析植被退化过程中主要环境因子的变化。在植被退化的过程中,由于植被群落结构和物种组成的退化,主要的小气候环境因子均发生比较明显的变化,主要表现:针阔混交林类型群落和常绿阔叶林类型群落照度的垂直差异和时间变化非常小,而草丛群落以及灌丛群落的照度存在比较明显的垂直差异,光照强度随高度的增加而增大,在150cm以上的高度,照度的时间变化比较明显;针阔混交林类型群落和常绿阔叶林类型群落气温的垂直变化非常小,一般在0．5℃以下,在监测时段内其气温的变化幅度在2℃左右,而草丛群落和灌丛群落气温的垂直变化和时间变化相对较大,气温垂直变化的幅度最大可达到6℃; 针阔混交林类型群落和常绿阔叶林类型群落空气相对湿度的垂直变化不明显,变化范围一般在5％以下,草丛群落和灌丛群落空气相对湿度的变化幅度比较大,最大可达25％;常绿阔叶林类型群落的土壤内部温度变幅最小,在0．5℃以下,而灌丛群落的波动幅度较大,可达8℃左右。总体而言,在植被退化过程中,光照强度、空气温度、土壤温度和气地温差不断增大,空气湿度逐渐降低,同时,主要小气候环境因子的时空波动性从平缓渐趋剧烈。 相似文献
12.
以泥鳅河和科洛河流域为例分析了土地利用/土地覆被变化与河流径流量的关系。森林覆被变化导致了流域用水量的减少,而这部分并没有形成地表径流,而是存储在了森林和草地转变成的沼泽湿地中。科洛河流域耕地和林地面积的减少增加了地表径流,而且林地变化的影响大于耕地的变化。流域土地覆被变化与流域河流径流量的关系复杂,并非单一的覆被类型变化起主导作用,而是各种变化耦合作用影响了河流径流,但其中影响最为显著的是沼泽湿地的变化。 相似文献
13.
江西退化红壤人工重建森林土壤微生物碳源代谢功能研究 总被引：5，自引：0，他引：5
应用MicroResp方法研究4种重建森林土壤微生物对不同类型碳源的代谢特征,自然恢复地为对照处理。结果表明,不同培养时间(6 h和继续培养18 h)和不同土壤深度(0~10和10~20 cm),土壤微生物对单一碳源的利用能力差异显著。4种重建森林土壤微生物对碳源利用能力有显著差异,表现为:自然恢复地阔叶混交林阔叶纯林针阔混交林针叶纯林。多样性指数和均匀度指数表明4种重建森林土壤微生物群落多样性的变化趋势为:自然恢复地阔叶混交林阔叶纯林针阔混交林针叶纯林,除自然恢复地外,土壤微生物的多样性和均匀度在4种不同重建森林类型之间差异不显著。主成分分析结果表明,所选15种碳源能够阐述4种不同重建森林土壤微生物功能多样性的差异,森林土壤微生物的敏感碳源主要为糖类。 相似文献
14.
《Communications in Soil Science and Plant Analysis》2012,43(17):2331-2340
The impact of land use on soil organic matter was investigated. Five land cover types (pine forest, olive groves, wheat, wheat/maize cultivation systems, and a shrub pasture) belonging to three land-use categories from the same catchment in the island of Lesvos, Greece, were used. The soils developed under similar pedogenetic processes and accepted similar agricultural practices for at least 30 years. The results showed that the land-use and cover types ranged according to their total soil carbon (C) content as follows: forest > double cultivation > wheat > olive > pasture. Crop plantations contained 31 to 40% less C at their upper 0- to 45-cm layer than forest. Pasture had shallow soils with a small C accumulation but high C concentration, whereas olive groves had the lowest concentrations of both soil C and nitrogen (N). Olive grove soils were the most prone to degradation but possessed the greatest potential for C sequestration. 相似文献
15.
为给三峡库区理水调洪型植被建设提供一定依据,在三峡库区重庆缙云山5种典型土地利用类型(混交林,阔叶林,楠竹林,灌木林及农地)建立坡面径流小区,从产流量、产流历时和产流过程来研究坡面产流对暴雨的响应。结果表明:在相同暴雨条件下,楠竹林地表径流深分别为混交林的2．7倍,为灌木林的3．7倍,为农地的4．5倍,为阔叶林的5．7倍。混交林和阔叶林的地下径流深比其他土地利用类型大一个数量级,为其他土地利用类型的 8-10倍。混交林坡面径流产流历时可延长248min,农地最少,仅为33 min。混交林地下产流历时可延长59 h;阔叶林居次,为50 h;农地产流历时缩短近11h。楠竹林坡面径流峰值约为混交林和灌木林的2倍,为阔叶林和农地的3倍。阔叶林和混交林地下径流峰值比楠竹林大2个数量级,比灌木林和农地大1个数量级。因此,重庆缙云山各土地利用类型中,混交林和阔叶林理水调洪功能最强,楠竹林理水调洪功能最差。 相似文献
16.
森林植被截留对大气污染物湿沉降的影响 总被引：3，自引：0，他引：3
试验研究了裸地、马尾松林、香樟林的大气降水、穿透雨和树干径流以及地表径流的污染物离子浓度。结果表明:大气降水的污染物质离子浓度大小依次为SO42->NO3->Cl->F-;马尾松、香樟林群落的穿透雨、树干径流的污染物质含量显著高于大气降水,说明它们对降水中污染离子的富集作用很强,马尾松林的穿透雨和树干径流的污染物离子的总量高于香樟林。各林型大气污染物降水的SO42-离子含量都较高,两种林型的地表径流污染物质含量显著高于大气降水,但污染物浓度比树干径流有显著降低,说明土壤表面和枯枝落叶对降水中污染物的吸附能力很强。 相似文献
17.
通过对珠江源头区几种主要的植被类型——云南松林、华山松林、云南松＋栓皮栎、云南松＋旱冬瓜林、早冬瓜林、滇石栎林、高山栎林等林分土壤的水源涵养功能进行研究，分别从土壤吸湿水分的能力、枯落物截留状况、渗透性能以及水土流失状况方面进行了分析．认为：阔叶林地表枯落物含量较多，分解速度也最快，土壤渗透功能及持水能力也最强，其次为针阔混交林，针叶纯林的持水保土功能最差。地表径流量以针阔混交林〈阔叶林〈针叶林依次递减．但其差异较大，地表径流最大的云南松针叶林是最小的高山栎灌丛的2．18倍，泥沙量最大的云南松林是最小的云南松＋栓皮栎林的25．65倍，而阔叶林与针阔混交林差异不大，研究表明针叶林下土壤的水分涵养功能较差，而针阔混交林和阔叶林则较强。 相似文献
18.
[目的]明确滇东石漠化地区不同恢复模式效果差异以及养分对酶的影响关系,为石漠化地区恢复措施提供理论依据。[方法]以土壤酶活性为恢复效果的衡量指标,采取基于模糊数学的土壤质量评价办法,得到不同模式下土壤酶指数,用以比较恢复模式的效果。基于土壤理化性质与酶活性相关性分析的结果,采取结构方程模型量化土壤理化环境和酶活性环境,进而分析不同土壤理化环境对不同酶环境的影响。[结果]酶活性大小排序为:灌草模式针阔混交林模式阔叶林模式针叶林模式裸地;由结构方程模型和有机质、全磷估计出的养分子环境对由脲酶活性、过氧化氢酶、多酚氧化酶活性构成的酶活性环境存在显著正影响。[结论]灌草模式和针阔混交林模式对石漠化恢复有较好作用。养分环境对酶活性环境的影响系数为0.87。 相似文献
19.
Hedgerows have been proposed as habitat and conservation corridor for forest plant species, but their importance for the survival of these species is still not clear. The objective of our study was to examine the frequency of occurrence of forest species and total forest species richness in different parts of the hedgerows, and to relate these patterns of occurrence to the species’ habitat requirements and life history traits. We surveyed in total 130 forest-hedgerow transects in North-western Germany, including three age classes.About 77% of all forest plant species (including some endangered taxa) occurring in the neighbouring forests were also found in the adjacent hedgerows. In all age classes, there was a negative relationship between distance from the forest-hedgerow ecotone and the number of species. Ancient hedgerows were not significantly more species-rich than more recent ones. Within 100 m distance from the forest edge, forest species richness increased with an increasing number of species in the nearby forest and with an increasing cover of the tree canopy as well as a decreasing cover of the shrub layer. Species with high frequency had comparatively high Ellenberg indicator values for light, and were mostly associated with anemochorous and epizoochorous seed dispersal.The frequency of occurrence in hedgerows of species with common attributes was partly in agreement, partly in disagreement with the results obtained in previous studies. We conclude that patterns are difficult to generalize, probably due to a strong regional variation in the pool of forest species and in the specific environments of both forests and hedgerows. 相似文献
20.
B.D. Amiro A.L. Orchansky A.G. Barr T.A. Black S.D. Chambers F.S. Chapin III M.L. Goulden M. Litvak H.P. Liu J.H. McCaughey A. McMillan J.T. Randerson 《Agricultural and Forest Meteorology》2006,140(1-4):41
Fire in the boreal forest renews forest stands and changes the ecosystem properties. The successional stage of the vegetation determines the radiative budget, energy balance partitioning, evapotranspiration and carbon dioxide flux. Here, we synthesize energy balance measurements from across the western boreal zone of North America as a function of stand age following fire. The data are from 22 sites in Alaska, Saskatchewan and Manitoba collected between 1998 and 2004 for a 150-year forest chronosequence. The summertime albedo immediately after a fire is about 0.05, increasing to about 0.12 for a period of about 30 years and then averaging about 0.08 for mature coniferous forests. A mature deciduous (aspen) forest has a higher summer albedo of about 0.16. Wintertime albedo decreases from a high of 0.7 for 5- to 30-year-old forests to about 0.2 for mature forests (deciduous and coniferous). Summer net radiation normalized to incoming solar radiation is lower in successional forests than in more mature forests by about 10%, except for the first 1–3 years after fire. This reduction in net radiative forcing is about 12–24 W m−2 as a daily average in summer (July). The summertime daily Bowen ratio exceeds 2 immediately after the fire, decreasing to about 0.5 for 15-year-old forests, with a wide range of 0.3–2 for mature forests depending on the forest type and soil water status. The magnitude of these changes is relatively large and may affect local, regional and perhaps global climates. Although fire has always determined stand renewal in these forests, increased future area burned could further alter the radiation balance and energy partitioning, causing a cooling feedback to counteract possible warming from carbon dioxide released by boreal fires. 相似文献