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1.
岷江上游1974-1995年间景观变化   总被引:10,自引:0,他引:10  
Landscape changes were traced over the 20 years from 1974 to 1995 in the upper Minjiang River basin, one of the most important forest regions in China, based on satellite image interpretation to provide basic data for local decision-making as well as sustainable landscape use and management. Results revealed that landscape from 1974 to 1995 changed at the regional scale as the area of forestland decreased, while cropland, shrubland, economic forest, grassland, and built-up land increased. Landscape changes mainly occurred in forestland, shrubland, grassland, economic forest, and built-up land. Moreover, the changes among forestland, shrubland, and grassland were the largest, influencing the whole characteristics of the changes in the basin. Analysis of the changes between 1974 and 1995 in the study area indicated that landscape heterogeneity and fragmentation increased, whereas landscape connectivity decreased. There were multiple reasons for landscape changes. A principal component analysis (PCA) was used to quantitatively study driving forces of landscape changes. The PCA results showed that economic and population factors were the principal driving forces of landscape changes from 1974 to 1995 in the upper Minjiang River basin, and that PCA was a suitable method for investigating driving forces of landscape changes.  相似文献   

2.
This paper introduces briefly two remote sensing case studies on land use in the subtropic region of China. One is on slope land use in the Yangtze River Three Gorges area. This is a large area of 60497 km2. First of all, geometric correction and supervised classification were conducted for ten scenes of Landsat-5 TM or MSS images. The resolution of the processed images is 50 m × 50 m on ground. By the classification the land use/cover categories in this area were discriminated. Then the croplands including rice fields and upland fields were extracted from the land use/cover maps. Simultaneously the slope grade maps were prepared based on the topographic maps. Overlaying the slope grade maps and the cropland maps, the area and percentage of the croplands in different slope grades were determined. This case study indicated that 71.5% of the uplands was situated on the slope above 150 and 25% on the slope above 250 in this area. It is dangerous, and urgent cultivation or engineering measures should be taken. Another case study is on soil erosion in Linshan County of Guangxi Province. Airphoto interpretation and supervised classification of a Landsat TM image were carried out for discriminating land cover/use categories in an area of 3 557.8 km2. And the soil erosion intensity grades were determined according to the land cover/use maps and slope maps. It wad discovered that the land suffering soil erosion accounted for 2404.0 km2, 67.6% of the total area of the county. Necessary measures to control soil erosion should be taken also.  相似文献   

3.
土地利用对土壤线虫营养类群垂直分布和季节变化的影响   总被引:1,自引:0,他引:1  
A field investigation was conducted at the Shenyang Experimental Station of Ecology, Chinese Academy of Sciences, in an aquic brown soil of Northeast China under three land use types (cropland, abandoned cropland, and woodland) in order to evaluate whether the vertical distribution and seasonal fluctuation for the number of total nematodes and trophic groups could reflect soil ecosystem differences and to determine the relationships between soil chemical properties and soil nematodes. The majority of soil nematodes were present in the 0-20 cm soil layers, and for these land use types plant parasites were the most abundant trophic group. In the abandoned cropland the numbers of plant parasites reached a peak on the August sampling date, whereas the cropland and woodland peaked on the October sampling date. Meanwhile, in all land use types the number of total nematodes, bacterivores, plant parasites, and omnivores-predators was negatively (P 〈 0.05, except for bacterivores in cropland, which was not significant) correlated with bulk density, and positively (P 〈 0.05, except for fungivores in abandoned cropland, which was not significant) correlated with total organic carbon and total nitrogen.  相似文献   

4.
多源卫星遥感影像进行土地利用变化监测   总被引:1,自引:0,他引:1  
Due to inappropriate planning and management, accelerated urban growth and tremendous loss in land, especially cropland, have become a great challenge for sustainable urban development in China, especially in developed urban area in the coastal regions; therefore, there is an urgent need to effectively detect and monitor the land use changes and provide accurate and timely information for planning and management. In this study a method combining principal component analysis (PCA) of multisensor satellite images from SPOT (systeme pour l'observation de la terre or earth observation satellite)-5 multispectral (XS) and Landsat-7 enhanced thematic mapper (ETM) panchromatic (PAN) data, and supervised classification was used to detect and analyze the dynamics of land use changes in the city proper of Hangzhou. The overall accuracy of the land use change detection was 90.67% and Kappa index was 0.89. The results indicated that there was a considerable land use change (10.03% of the total area) in the study area from 2001 to 2003, with three major types of land use conversions: from cropland into built-up land, construction site, and water area (fish pond). Changes from orchard land into built-up land were also detected. The method described in this study is feasible and useful for detecting rapid land use change in the urban area.  相似文献   

5.
To build a rapid and accurate method for greenhouse vegetable land information extraction using an index model derived from TM digital data of Qingzhou City, Shandong Province, based on a systematic analysis of the spectral characteristics of different land use types in the study area, a subset of the image was first made to eliminate the mountainous region not associated with vegetable distribution, and then water body pixels were masked. With this the VI index model for greenhouse vegetable land extraction was developed. The index model indicated greenhouse vegetable land for Qingzhou in April 2002 was concentrated in the southeast and around rural residential areas. Field data used for an accuracy evaluation showed that greenhouse hectares determined with remote sensing were 95.9% accurate, and accuracy for the spatial distribution of greenhouse vegetable land cross checked with a random sample was 96.3%. Therefore, this approach provided an effective method for greenhouse vegetable land information extraction and has potential significance for management of greenhouse vegetable production in the study area, as well as North China.  相似文献   

6.
Tea(Camellia sinensis) is one of the most valuable cash crops in southern China;however,the planting distribution of tea crops is not optimal and the production and cultivation regions of tea crops are restricted by law and custom.In order to evaluate the suitability of tea crops in Zhejiang Province,the annual mean temperature,the annual accumulated temperature above 10 C,the frequency of extremely low temperature below 13 C,the mean humidity from April to October,slope,aspect,altitude,soil type,and soil texture were selected from climate,topography,and soil factors as factors for land ecological evaluation by the Delphi method based on the ecological characteristics of tea crops.These nine factors were quantitatively analyzed using a geographic information system(GIS).The grey relational analysis(GRA) was combined with the analytic hierarchy process(AHP) to address the uncertainties during the process of evaluating the traditional land ecological suitability,and a modified land ecological suitability evaluation(LESE) model was built.Based on the land-use map of Zhejiang Province,the regions that were completely unsuitable for tea cultivation in the province were eliminated and then the spatial distribution of the ecological suitability of tea crops was generated using the modified LESE model and GIS.The results demonstrated that the highly,moderately,and non-suitable regions for the cultivation of tea crops in Zhejiang Province were 27 552.66,42 724.64,and 26 507.97 km 2,and accounted for 28.47%,44.14%,and 27.39% of the total evaluation area,respectively.Validation of the method showed a high degree of coincidence with the current planting distribution of tea crops in Zhejiang Province.The modified LESE model combined with GIS could be useful in quickly and accurately evaluating the land ecological suitability of tea crops,providing a scientific basis for the rational distribution of tea crops and acting as a reference to land policy makers and land use planners.  相似文献   

7.
X. Y. WANG  Y. ZHAO  R. HORN 《土壤圈》2010,20(1):43-54
Depth distribution of soil wettability and its correlations with vegetation type, soil texture, and pH were investigated under various land use (cropland, grassland, and forestland) and soil management systems. Wettability was evaluated by contact angle with the Wilhelmy plate method. Water repellency was likely to be present under permanently vegetated land, but less common on tilled agricultural land. It was mostly prevalent in the topsoil, especially in coarse-textured soils, and decreased in the subsoil. However, the depth dependency of wettability could not be derived from the investigated wide range of soils. The correlation and multiple regression analysis revealed that the wettability in repellent soils was affected more by soil organic carbon (SOC) than by soil texture and pH, whereas in wettable soils, soil texture and pH were more effective than SOC. Furthermore, the quality of SOC seemed to be more important in determining wettability than its quantity, as proofed by stronger hydrophobicity under coniferous than under deciduous forestland. Soil management had a minor effect on wettability if conventional and conservation tillage or different grazing intensities were considered.  相似文献   

8.
青州市精作农区耕地不同利用方式对土壤养分的影响研究   总被引:4,自引:0,他引:4  
On the basis of the data obtained from a field survey, the relationship between land use and soil nutrients was evaluated in Qingzhou County, Shandong Province, China, through a statistical analysis of differences in 17 nutrients in five types of cultivated land. The results showed significant effects (P≤0.05 or P ≤ 0.01) of land-use type on soil organic matter and concentration of macronutrients, secondary nutrients, and micronutrients, as well as total salt and soil pH. In vegetable land, because of the large amounts of fertilizer applied to vegetable crops, the concentrations of most soil nutrients, with exception of available Si and micronutrients, were higher than those in grain cropland. Grain cropland had a significantly lower total salt content (P ≤ 0.01) and tended to have a higher soil pH than vegetable land. Within subtypes of land use, dry land, irrigable land, and open-air vegetable land had the highest coefficient of variation (CV) for available P, whereas protected vegetable land had the highest CV for total N and available S. In general, land-use types had greater impact on macronutrients than on secondary nutrients and micronutrients.  相似文献   

9.
Soil organic carbon(SOC) is an important component of farming systems and global carbon cycle. Accurately estimating SOC stock is of great importance for assessing soil productivity and modeling global climate change. A newly built 1:50 000 soil database of Zhejiang Province containing 2 154 geo-referenced soil profiles and a pedological professional knowledge-based(PKB) method were used to estimate SOC stock up to a depth of 100 cm for the Province. The spatial patterns of SOC stocks stratified by soil types,watershed(buffer analysis), topographical factors, and land use types were identified. Results showed that the soils in Zhejiang covered an area of 100 740 km2 with a total SOC stock of 831.49 × 106 t and a mean SOC density of 8.25 kg m-2, excluding water and urban areas. In terms of soil types, red soils had the highest SOC stock(259.10 × 106t), whereas mountain meadow soils contained the lowest(0.15 × 106t). In terms of SOC densities, the lowest value(5.11 kg m-2) was found in skel soils, whereas the highest value(45.30 kg m-2) was observed in mountain meadow soils. Yellow soils, as a dominant soil group, determined the SOC densities of different buffer zones in Qiantang River watershed because of their large area percentage and wide variation of SOC density values.The area percentages of various soil groups significantly varied with increasing elevation or slope when overlaid with digital elevation model data, thus influencing the SOC densities. The highest SOC density was observed under grassland, whereas the lowest SOC density was identified under unutilized land. The map of SOC density(0–100 cm depth) and the spatial patterns of SOC stocks in the Province would be helpful for relevant agencies and communities in Zhejiang Province, China.  相似文献   

10.
厦门市土地利用变化的时空格局及驱动力   总被引:15,自引:0,他引:15  
Using Landsat TM data of 1988, 1998 and 2001, the dynamic process of the spatial-temporal characteristics of land use changes during 13 years from 1988 to 2001 in the special economic zone of Xiamen, China was analyzed to improve understanding and to find the driving forces of land use change so that sustainable land utilization could be practiced. During the 13 years cropland decreased remarkably by nearly 11 304.95 ha. The areas of rural-urban construction and water body increased by 10 152.24 ha and 848.94 ha, respectively. From 1988 to 2001, 52.5% of the lost cropland was converted into rural-urban industrial land. Rapid urbanization contributed to a great change in the rate of cropland land use during these years. Land-reclamation also contributed to a decrease in water body area as well as marine ecological and environmental destruction. In the study area 1) urbanization and industrialization, 2) infrastructure and agricultural intensification, 3) increased affluence of the farming community, and 4) policy factors have driven the land use changes. Possible sustainable land use measures included construction of a land management system, land planning, development of potential land resources, new technology applications, and marine ecological and environmental protection.  相似文献   

11.
秦巴山区土地利用时空格局及地形梯度效应   总被引:11,自引:3,他引:8  
张静  任志远 《农业工程学报》2016,32(14):250-257
自然景观的垂直地带性为区域土地利用的垂直景观格局奠定了基础,同时也决定了垂直景观带上土地利用的强度及其变化情况。该文采用地形位指数、分布指数、土地利用程度综合指数和土地利用信息图谱法等,分析了1989-2010年秦巴山区土地利用格局的地形梯度效应和图谱信息,揭示地形控制下土地利用时空格局和土地转移的变化规律。结果表明:1)秦巴山区土地利用以林地和耕地为主,呈西林东耕分布;1989-2010年间林地减少显著,建设用地增加明显,其中耕地是建设用地主要转入来源,林、草地是耕地主要转入来源。2)秦巴山区各生态亚区用地类型差异明显,各生态亚区土地利用转移方向也存在差异性。3)秦巴山区土地利用强度指数呈东高西低,中高周低的态势;土地利用强度变化率稳定少动,增加趋势不明显;土地利用动态度呈中高周低的态势,整体变化不大。4)水域、建设用地和耕地主要集中在地形起伏度小和坡度小的低地形位,且耕地主要转移为其他两种用地类型,建设用地有向中低地形位分布的趋势。林地和草地集中在地形起伏大、坡度陡的中高地形位,且存在着相互转移演替现象,中低地形位往往是耕地、林地、草地间的相互转换,未来势必加强坡耕地和低山丘陵区林草地的管治工作。  相似文献   

12.
巫山县地处三峡库区腹地,不仅是三峡移民安置区重点建设区域之一,更是研究三峡库区土地利用变化的典型个案。以巫山县1990年和2010年的Landsat TM遥感数据为主要数据源,基于RS和GIS技术获取研究区的土地利用数据,应用土地利用变化模型探究该区域20年间土地利用时空演变特征,借助Markov模型建立其土地利用格局预测,探究今后土地利用类型变化特征和发展趋势。结果表明:研究区地利用类型总体呈现出以林地、草地和耕地为主体的农林生产格局现状;20年间林地、草地、园地、水域和居民工矿用地面积增加,耕地和未利用地面积减少,水域和耕地面积增加和减少的最多,分别为47.67km~2,136.10km~2;林地和水域具有较高的未变化率(保留率),未利用地变化率最小,林地和耕地之间具有较高的转换率,林地新增面积最大,变化速率最小,居民工矿用地变化速率最大;2090年后,研究区土地利用基本达到相对稳定状态,林地、耕地、草地、水域、居民工矿用地、未利用土地和园地的面积比重分别为52.96%,6.15%,26.69%,8.71%,1.38%,0.04%和3.97%。  相似文献   

13.
基于RS和GIS的滨州城区土地利用变化研究   总被引:1,自引:1,他引:0       下载免费PDF全文
[目的]研究山东省滨州城区在城市化过程中的土地利用变化规律,为城区土地合理规划和利用提供参考。[方法]以Landsat影像为主要数据源,获取滨州城区1996—2014年5期土地利用分类信息,引入土地利用动态度、转移矩阵和土地利用空间重心,定量分析城区土地利用时空变化规律。[结果]1996—2014年,耕地以平均3.63%/a的速率减少,林地、水体和建设用地表现出增加的趋势,变化率分别为5.43%/a,0.79%/a和5.70%/a。林地和水体以转出为主变为转入量大于转出量,2005—2009年时段林地转入量出现峰值,2001—2005年时段水体转入量达到峰值。耕地和建设用地重心分别位于市政广场的西南侧和东侧,耕地重心往西南方向远离市政广场,建设用地重心往西迁移逐渐靠近市政广场。[结论]城区土地利用变化表现为耕地面积不断减少,林地和水体面积先减后增,建设用地面积不断增加的总体趋势,土地利用转移主要发生在耕地和建设用地之间,林地和水体转移受城区水利工程和绿化工程实施的影响较大,建设用地重心迁移与西城区的开发建设密切相关。  相似文献   

14.
基于CA-Markov的哈尔滨市土地利用变化及预测   总被引:15,自引:4,他引:11  
为探讨哈尔滨城市化进程中土地利用时空演变规律以及驱动机制。该文以1989年、2001年和2007年LandsatTM影像为数据源,借助于地学信息谱图理论,运用RS和GIS技术分析研究区域18a土地利用格局变化,以2007年土地利用格局为基础,利用CA-Markov模型和并引入终极状态概率,预测2025年土地利用情况和平衡状态下土地利用空间分布格局。研究结果表明:区域土地利用格局以耕地为主,其面积比例均超过60%,其次是林地和居民工矿用地;稳定型图谱空间分布广泛,占研究区域总面积比例最大,"耕地→耕地→耕地"是其面积最大的变化图谱,"林地→林地→林地"次之,持续变化型所占比例最小,"未利用地→林地→耕地"是其面积最大的变化图谱;CA-Markov模型预测结果表明从2025年到土地利用终极状态期间,耕地面积持续减少,居民工矿用地持续增加,耕地→居民工矿用地是其主要转化轨迹,其他地类变化量相对较小,基本上处于动态平衡状态中,该文为土地利用合理规划、生态恢复和区域经济发展提供依据。  相似文献   

15.
北方农牧交错带是中国北方农业和畜牧业交错地带,是中国典型的生态脆弱区.选取陕西省北部靖边县为研究区,以1990,2000和2010年3期TM/ETM+影像及社会经济数据为基础,利用土地利用动态度和转移矩阵分析了靖边县1990-2010年土地利用变化及其驱动因素.研究表明:(1) 1990-2010年,靖边县林地、建设用地面积呈现增加态势,耕地、草地、水域和未利用地面积为减少态势.(2) 1990-2010年,靖边县土地利用变化主要发生于2000年之后,其中尤以建设用地的快速增加为特点.(3) 1990-2000年,靖边县耕地、林地和草地之间的相互转变数量较大,且共同向建设用地转变.这种变化主要集中于北部风沙滩区.(4)经济的快速发展尤其是油气等资源的开采是靖边县建设用地变化的主要驱动因素,退耕还林还草等政策的实施,是耕地、林地、草地发生变化的主要驱动因素.  相似文献   

16.
黄土高原1999年开始的退耕还林(草)工程,对植被覆盖与土地利用结构产生了深刻影响,评估黄土高原未来植被恢复潜力、植树造林适宜区以及土地利用变化,对黄土高原生态保护和高质量发展具有重要意义。该研究基于北洛河流域2020年下垫面状况,借鉴"相似生境法",对不同地貌类型区的未来恢复潜力、植树造林适宜区与土地利用变化进行了分析。结果表明:1)丘陵沟壑区目前平均植被盖度为61.9%,未来20~30 a仍有9.2%左右的上升空间,植被可恢复土地面积约占丘陵区的36.4%。土石山林区尚有11.5%的土地面积具有恢复余地,高塬沟壑区与阶地平原区植被盖度恢复余地很小。2)未来土地利用变化面积主要集中在丘陵沟壑区,与2020年相比,其耕地将减少47.4%,而林地与草地会增加0.7%与15.8%。土石山林区耕地将减少23.0%,林地与草地分别会增加0.2%与36.0%。3)基于"适地适树"原则下的情景模拟,高塬沟壑区与阶地平原区分别有279.16、233.73 km2面积可植树造林,而丘陵沟壑区大片可退耕土地适宜于自然恢复。结果表明,丘陵沟壑区仍是未来生态恢复重点关注区域,是黄河流域生态保护和高质量发展的热点区域。  相似文献   

17.
亚热带耕地土壤酸化程度差异及影响因素   总被引:7,自引:1,他引:6  
准确揭示区域耕地土壤酸化程度及其原因对于耕地质量提升和农业可持续发展具有重要意义。本研究利用地处亚热带的福建省1982年36 777个和2008年236 445个耕地表层土壤调查样点属性建立的1∶25万耕地土壤数据库,借助GIS技术与灰色斜率关联分析模型探讨了26年间全省耕地土壤酸化程度及其原因,为省域耕地土壤酸性调控提供科学依据。结果表明:1982—2008年间福建省67.60%的耕地土壤发生不同程度酸化,其中强度、中度和弱度酸化面积分别占全省耕地总面积的0.83%、18.26%和48.52%。就行政区域差异而言,强度酸化耕地主要分布在龙岩市,占全省强度酸化耕地总面积的86.88%,其次为泉州市,占比为8.39%;中度酸化耕地主要分布在南平市、龙岩市和泉州市,分别占全省中度酸化耕地总面积的29.88%、18.10%和16.94%,弱度酸化耕地则遍布全省各县市区。从土壤类型差异来看,潜育水稻土、渗育水稻土和酸性紫色土亚类的酸化面积比例较大,分别占相应亚类总面积的82.87%、72.37%和69.20%;但渗育和潴育水稻土亚类的酸化程度较为严重,强度、中度和弱度酸化的渗育和潴育水稻土面积分别占全省耕地相应酸化程度总面积的98.94%、84.51%和87.36%。从土地利用类型差异分析,水田和水浇地的酸化面积比例较高,分别占相应利用类型总面积的70.35%和60.78%。灰色斜率关联分析模型分析表明,1982—2008年间酸雨、高温多雨气候及化肥大量施用是引起福建省耕地土壤酸化的主要外因,故严控工业含硫等酸性废气排放进而控制酸雨和合理调整施肥结构是减缓全省耕地土壤酸化的必要途径。  相似文献   

18.
基于地形梯度的哈尔滨市土地利用格局变化分析   总被引:19,自引:7,他引:12  
为揭示土地利用格局变化在地形差异上的演变过程,探讨不同地貌部位自然因素和人文因素在土地利用变化过程中的作用,以1989年、1995年、2001年和2007年Landsat TM/ETM+影像为主要数据源,在RS和GIS支持下获取土地利用数据。基于地学信息图谱分析理论,研究该区域不同时期土地利用空间格局变化进程,揭示土地利用变化成因和机理,并基于DEM(digital elevation model)探究土地利用图谱地形梯度的空间分异和时空演变规律。结果表明:土地利用结构以耕地和林地为主,耕地和未利用地面积持续减少,平均斑块面积分别由20.96km2减少到2.87km2和3.92km2减少到0.09km2,破碎化程度加剧,且未利用地(滩涂地和湿地)→耕地是其主要的转变轨迹,居民工矿用地呈现不平衡的增加态势,耕地是居民工矿用地和林地的主要转化来源,林地的破碎度由0.117个/km2增加到0.532个/km2,破碎化程度日益严重;前期变化型和持续变化型的分布指数在地形位等级2时最大,稳定型和反复变化型的在地形位等级1时最大,之后随着地形位的增加而减小;中间过渡型呈现一定的曲线变化。该文为城市化过程中的土地资源的合理规划和利用提供科学依据。  相似文献   

19.
根据甘肃省天水市罗峪沟流域1986年矢量格式的土地详查数据库,1990年、1995年和2001年的Landsat TM影像数据,利用地理信息系统和遥感技术,结合空间分析技术和数理统计方法,分析了天水市罗峪沟流域土地利用的数量变化和空间变化特征.明确了研究区主要的土地利用类型,研究区综合土地利用动态度和研究区主要的土地利用类型之间的转移及其速度.结果显示:近11 a该流域土地利用以耕地和林地为主,两者占土地总面积的80%以上;研究区1990-1995年综合土地利用动态度为0.23%,1995-2001年综合土地利用动态度为1.09%,1990-2001年综合土地利用动态度达0.89%;土地利用类型转移的主要方向是向林地转移,占总变化面积的86.82%.其次是转向草地.占总变化面积的10.93%.再次是转向耕地和未利用地,分别占总变化面积的1.183%和1.060%.耕地流向林地的转移速度平均每年35.67 hm~2;耕地的另一个主要流向是草地,其平均每年转移速度3.41 hm~2;未利用土地减少的幅度也比较大,其主要的转向是林地,平均每年转移速度6.09 hm~2;未利用地另外一个转移方向是草地,平均每年的转移速度是1.77 hm~2;河床地流出方向主要是林地,其平均每年转移速度是5.31hm~2;其次是未利用地和耕地,其平均每年的转移速度分别为0.58 hm~2和0.16 hm~2;还有其它各种类型之间的转移,其平均每年的转移速度相对较小.  相似文献   

20.
丹江鹦鹉沟小流域土壤侵蚀和养分损失定量分析   总被引:5,自引:1,他引:4  
小流域土壤侵蚀量和养分损失量的定量研究可为南水北调水源区的生态保护、水土保持和生态补偿提供重要的依据.该文在地理信息技术(geographic information system,GIS)的支持下,应用修正通用土壤流失方程(revised universal soil loss equation,RUSLE)估算了丹江鹦鹉沟流域的土壤侵蚀量和养分损失量,并进行了土壤侵蚀强度分级.结果表明,流域的年均土壤侵蚀模数为3140 t/km2,侵蚀强度为中度.其中强度侵蚀以上的土地面积占流域总面积的24.1%,侵蚀量为4573.0 t,却占年侵蚀总量的84.8%,其主要是坡度较大的坡耕地,是流域需要重点治理的区域.不同土地利用类型的土壤侵蚀量差异较大,林地、草地和农地的年均土壤侵蚀模数分别为509.7、1511.8和4606.5 t/km2.林草地年侵蚀量较小,农地土壤侵蚀量占流域总侵蚀量的95.3%.坡度每增加5°,不同土地利用的土壤侵蚀模数增加量比坡长每增加5 m的增加量要大1~2倍.研究区表土流失造成的全氮、全磷和有机质损失量分别为3.81、3.52和101.45 t,其中农地的养分损失量最为严重.流域泥沙中全氮、全磷和有机质的年均流失模数分别为1.01、0.75和38.43 t/(km2×a).该研究可为水源区水土流失和非点源污染治理以及清洁小流域建设提供科学依据.  相似文献   

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