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1.
新疆艾比湖流域平原区景观土壤属性特征研究   总被引:1,自引:0,他引:1  
以新疆艾比湖流域平原区为对象,在对研究区进行景观生态分类及野外调查验证的基础上,利用"3S"技术将1∶100×104的新疆土壤类型图与研究区景观类型图叠加,从土壤属性层次上对研究区各类景观的生态土壤类型进行确认,并分析其在研究区内分布的特征。结果表明:研究区主要土壤类型为26类,以石膏灰棕漠土所占比例最大,占研究区总面积的19.03%,棕钙土、荒漠风沙土、草甸盐土、盐化草甸土、和灌耕灰漠土等面积也较大。  相似文献   

2.
实验以野生沙枣为研究对象,在根系附近采集实验组土样,在周围裸露土地上采集对照组土样。通过实验组与对照组的各项指标对照表明,在盐渍土上种植沙枣,不但可增加土壤中的含水量,而且可增加土壤中的空气体积和有机质含量,提高土壤中的K含量,降低土壤中pH值。沙枣对滨海盐渍土有着很好的改良效果和一定的经济效益。  相似文献   

3.
宋国萍  宋川 《四川环境》2008,27(1):12-18
针对山区高速公路建设的特点和可能造成水土流失的影响及其分布特性,根据国内外对水土流失预测的研究现状,选择了位于西南土石山区在建国道108线西攀高速公路路段的黄水互通式立交A匝道开挖边坡和K11 100~K11 210路段左侧的弃渣场上进行了观测试验,通过15次降雨量和水土流失量的实测,经过降雨强度、各时段降雨动能、降雨总能量参数单因子和复合因子与土壤流失量的相关分析,得出试验区的天然降雨雨滴中数直径与雨强的对数关系和单位降雨强度与降雨动能的关系;初步提出适用于高速公路建设土壤流失预测中的降雨侵蚀力的计算公式、土壤可侵蚀因子值;修正了经验法中的加速侵蚀系数A值.  相似文献   

4.
秦皇岛海岸侵蚀动态研究   总被引:2,自引:0,他引:2  
利用不同时期的地形图、遥感图片对比,并选取典型海岸岸滩监测剖面实测数据,对海岸侵蚀现状进行了分析和定量计算。分析结果显示,秦皇岛海岸全线处于侵蚀状态,平均蚀退率1.5~4 m/a,根据蚀退率可将秦皇岛海岸划分为严重侵蚀、强侵蚀、侵蚀、微侵蚀、稳定5种岸线侵蚀类型。  相似文献   

5.
土壤盐渍化是影响区域生态环境稳定性以及制约农业生产发展的重要因素。对土壤特性进行研究是开展精细农业实践必要的基础研究。本文采用传统统计学方法、相关分析与主成分分析方法,分析新疆典型盐渍化区域渭-库绿洲的土壤含盐量、电导率、TDS、pH值、含水量及主要盐基离子的特征值以及相互之间的关系。结果显示,研究区土壤pH值相对稳定;土壤含盐量具有不均匀分布特征;土壤盐分的分布是有较强的表聚特征。绝大多数时间,矿化度与电导率,电导率与含盐量,SO_4~(2-)、Na~+、Cl~-等离子与表层土壤含盐量之间具有较好的正相关关系,而其他各指标之间的相关关系不太明显。研究区土壤中硫酸盐、氯化物在表层积聚相对强烈;土壤盐渍化类型是属于氯化物型,研究区土壤还在聚盐状态。  相似文献   

6.
本文探讨了小区域范围内土壤pH值与土壤主要肥力指标N、P、K有效态的关系,结果表明土壤pH值与土壤速效P含量呈极显著负相关,相关系数为-0.498;与土壤缓效K呈显著正相关,相关系数为0.352;与水解性N和速效K含量相关性不明显。  相似文献   

7.
新疆罗布泊野骆驼国家级自然保护区位于哈密、巴州、吐鲁番三地州.罗布泊是塔里木盆地最低的断陷洼地,也是第四纪以来盆地地表水的集水中心和积盐中心.1970年干涸后4000 km2的湖盆成为平坦的岩盐地,其外围分布着各种类型的盐壳、棕漠土、风沙土等极旱荒漠土壤,局部地段分布有草甸土、盐土等,山地分布有棕钙土、高寒荒漠土,各种土壤有其不同的特征.  相似文献   

8.
土壤渗滤系统具有处理效果好、投资少等优点,适合再生水或经过预处理农村生活污水的处理,逐步成为国内外的研究热点。采用新疆准噶尔盆地边缘的荒漠-绿洲交错地带的土壤,利用室内土柱装置,研究城市再生水在荒漠土壤中渗滤后进出水水质与土壤污染物含量的变化特征,探讨土壤性质对再生水氨氮去除率和土壤污染物浓度变化的影响。结果表明,荒漠土壤对再生水氨氮等有显著的去除作用,且再生水经过土柱渗滤后,在60 cm处的出水氨氮浓度逐渐趋于稳定,但氨氮去除率随时间并不十分稳定,且不同土壤质地、组分与性质不同,对氨氮的去除效果有明显差异。同一土柱,对不同污染物去除作用也有很大差异。通过相关性分析可知,土壤中的CO_3~(2-)、HCO_3~-、Na~+、SO_4~(2-)、总磷、碱解氮与硝酸盐氮等指标含量对再生水氨氮的去除率及土壤中污染物浓度变化有明显的影响。研究结果为进一步研究荒漠土壤渗滤系统去除污染物机理、新疆再生水安全利用以及荒漠土壤渗滤系统的实践应用提供基础。  相似文献   

9.
表土剥离对土地整治项目收益的影响研究   总被引:1,自引:0,他引:1  
刘雪冉  赵艳玲  李建华  信凯 《资源开发与保护》2012,(11):1025-1027,F0004
为了揭示表土剥离对土地整治项目收益的不同影响,作者采用采样分析、调查问卷、地统计分析、空间分析等方法对这种影响进行了分析。研究表明,表土剥离是土地整治工程必不可少的一步。通过土壤质量空间分布和作物投入一产出值比较分析,土地整治可有敬减少农业生产成本,而表土剥离可最大限度地保护土壤表层,通过追肥和田间管理,在2—3年时间可基本恢复耕地肥力。  相似文献   

10.
基于GIS手段分析2018年新疆沙化土地分布特征,从海拔、坡度、坡向因子等方面探讨新疆土地沙化发生的潜在原因和发展变化的主要驱动力。结果表明:新疆土地沙化程度有所减弱,总体上有所改善;新疆沙化土地海拔分布在500~1500 m范围内,坡度在0~6°范围内的缓坡是主要沙化区;就坡向而言,研究区阳坡方向土地沙化程度大于阴坡。研究结果可为新疆土地沙化防治提供数据支持。  相似文献   

11.
An erosion-based land classification system for military installations   总被引:3,自引:0,他引:3  
The universal soil loss equation (USLE) has been integrated with a geographic information system known as the geographical resources analysis support system (GRASS) to create a land classification system for use by military trainers and land managers to minimize the environmental impacts of military training activities. The USLE provides an estimate of current average annual sheet and rill erosion based upon factors representing climate, soil erodibility, topography, cover, and conservation support practices. The erosion estimate is compared to erosion tolerance values to produce an expression of the current erosion status. An index of inherent site erodibility is also achieved through manipulation of the USLE. Based on published soil surveys, satellite imagery, and ground-truth vegetation transects, data layers are created within GRASS for each of the component factors of the USLE. Appropriate mathematical operations are performed with the data layers, and color-coded maps are produced that represent the erosion status and erodibility index for each 50-m × 50-m area of soil surface. These maps aid military trainers and land managers in scheduling appropriate kinds and intensities of military training activities.  相似文献   

12.
The soil erodibility index (EI) of Conservation Reserve Program (CRP) lands, which was the major criterion for CRP enrollment, was assessed for six counties in southwestern Kansas using USGS seamless digital elevation model data and Geographical Informational System techniques. The proportion of land areas with EI values of 8 or lower was less than 1% of the entire study area and most of the land areas (72.5%) were concentrated on EI values between 8 and 24. Although land acreage with EI values of 24 or higher decreased dramatically, the proportion of CRP lands to the other land-use types did not change much from low to high EI levels. The soil EI and physical soil characteristics of the CRP lands were compared to those of other land-use types. In general, the mean EI values of the land-use types were strongly correlated with physical soil properties, including organic matter content, clay content, available water capacity, permeability, and texture. CRP lands were compared in detail with cropland in terms of their soil characteristics to infer the pivotal cause of the land transformation. Although there was no significant statistical difference in EI between cropland and CRP soils, soil texture, soil family, and permeability were statistically different between the two. Statistical analyses of these three variables showed that CRP soils had coarser texture and higher permeability on average than cropland soils, indicating that CRP lands in the study area are drier than cropland soils. Therefore, soil moisture characteristics, not necessarily soil erosion potential, might have been the key factor for CRP enrollment in the study area.  相似文献   

13.
SOIL EROSION AND SEDIMENT YIELD PREDICTION ACCURACY USING WEPP1   总被引:1,自引:0,他引:1  
ABSTRACT: The objectives of this paper are to discuss expectations for the Water Erosion Prediction Project (WEPP) accuracy, to review published studies related to WEPP goodness of fit, and to evaluate these in the context of expectations for WEPP's goodness of fit. WEPP model erosion predictions have been compared in numerous studies to observed values for soil loss and sediment delivery from cropland plots, forest roads, irrigated lands and small watersheds. A number of different techniques for evaluating WEPP have been used, including one recently developed where the ability of WEPP to accurately predict soil erosion can be compared to the accuracy of replicated plots to predict soil erosion. In one study involving 1,594 years of data from runoff plots, WEPP performed similarly to the Universal Soil Loss Erosion (USLE) technology, indicating that WEPP has met the criteria of results being “at least as good with respect to observed data and known relationships as those from the USLE,” particularly when the USLE technology was developed using relationships derived from that data set, and using soil erodibility values measured on those plots using data sets from the same period of record. In many cases, WEPP performed as well as could be expected, based on comparisons with the variability in replicate data sets. One major finding has been that soil erodibility values calculated using the technology in WEPP for rainfall conditions may not be suitable for furrow irrigated conditions. WEPP was found to represent the major storms that account for high percentages of soil loss quite well—a single storm application that the USLE technology is unsuitable for—and WEPP has performed well for disturbed forests and forest roads. WEPP has been able to reflect the extremes of soil loss, being quite responsive to the wide differences in cropping, tillage, and other forms of management, one of the requirements for WEPP validation. WEPP was also found to perform well on a wide range of small watersheds, an area where USLE technology cannot be used.  相似文献   

14.
Soil erosion is one of the most serious environmental and public health problems, and such land degradation can be effectively mitigated through performing land use transitions across a watershed. Optimal land use management can thus provide a way to reduce soil erosion while achieving the maximum net benefit. However, optimized land use allocation schemes are not always successful since uncertainties pertaining to soil erosion control are not well presented. This study applied an interval-parameter fuzzy two-stage stochastic programming approach to generate optimal land use planning strategies for soil erosion control based on an inexact optimization framework, in which various uncertainties were reflected. The modeling approach can incorporate predefined soil erosion control policies, and address inherent system uncertainties expressed as discrete intervals, fuzzy sets, and probability distributions. The developed model was demonstrated through a case study in the Xiangxi River watershed, China’s Three Gorges Reservoir region. Land use transformations were employed as decision variables, and based on these, the land use change dynamics were yielded for a 15-year planning horizon. Finally, the maximum net economic benefit with an interval value of [1.197, 6.311] × 109 $ was obtained as well as corresponding land use allocations in the three planning periods. Also, the resulting soil erosion amount was found to be decreased and controlled at a tolerable level over the watershed. Thus, results confirm that the developed model is a useful tool for implementing land use management as not only does it allow local decision makers to optimize land use allocation, but can also help to answer how to accomplish land use changes.  相似文献   

15.
Soil erosion under different vegetation covers in the Venezuelan Andes   总被引:13,自引:0,他引:13  
This comparative study of soil erosion considered different environments in an ecological unit of the Venezuelan Andes. The soils belong to an association of typic palehumults and humic dystrudepts. Soil losses were quantified by using erosion plots in areas covered by four types of vegetation, including both natural and cultivated environments. The highest soil erosion rate evaluated corresponded to horticultural crops in rotation: reaching a value of 22 Mg ha–1 per year. For apple tree (Malus sylvestris Miller) plots, soil losses reached values of 1.96 Mg ha–1 per year. Losses from pasture (Pennisetum clandestinum Hochst. ex Chiov.) plots, without livestock grazing, were as high as 1.11 Mg ha–1 during the second year of the experiment. The highest soil losses generated from plots under natural forest were equal to 0.54 Mg ha–1 per year. Environmental factors such as total and effective rainfall, runoff, and some soil characteristics as those related to soil losses by water erosion were evaluated. The type of management applied to each site under different land use type and the absence of conservation practices explain, to a large extent, the erosive processes and mechanisms.  相似文献   

16.
The goal of this research was to evaluate the relative effects of root density, freeze/thaw cycling, and soil properties on the erodibility and critical shear stress of streambanks. The erodibility and critical shear stress of rooted bank soils were measured in situ at 25 field sites using a submerged jet test device; several soil, vegetation, and stream chemistry characteristics shown to influence soil erosion were also assessed. Multiple linear regression analysis was conducted to determine those factors that most influenced streambank erodibility and the relative impact of riparian vegetation. Study results indicated that soil erosion is a complex phenomenon that depends primarily on soil bulk density. Freeze/thaw cycling, soil antecedent moisture content, the density of roots with diameters of 2 to 20 mm, soil texture, and the interaction of soil pore water and stream water had a significant impact on soil erodibility and critical shear stress, depending on soil type. Riparian vegetation had multiple significant effects on soil erodibility. In addition to reducing soil erodibility through root reinforcement, the streamside vegetation affected soil moisture and altered the local microclimate, which in turn affected freeze/thaw cycling (FTC). This study represents the first in situ testing of the erodibility of vegetated streambanks and provides a quantitative analysis on the effects of vegetation on streambank erosion, relative to other soil physical and chemical parameters.  相似文献   

17.
ABSTRACT: Benthic macroinvertebrate samples representing 151 taxa were collected in August 1995 to examine the linkage between land use, water quality, and aquatic biointegrity in seven tributaries of the Blackfoot River watershed, Montana. The tributaries represent silvicultural (timber harvesting), agricultural (irrigated alfalfa and hay and livestock grazing), and wilderness land uses. A 2.4 km (1.5 mile) reach of a recently restored tributary also was sampled for comparison with the other six sites. A geographic information system (GIS) was used to characterize the seven subwatersheds and estimate soil erosion, using the Modified Universal Soil Loss Equation, and sediment delivery. The wilderness stream had the highest aquatic biointegrity. Two agricultural streams had the largest estimated soil erosion and sediment delivery rates, the greatest habitat impairment from nonpoint source pollution, and the most impoverished macroinvertebrate communities. The silvicultural subwatersheds had greater rates of estimated soil erosion and sediment delivery and lower aquatic biointegrity than the wilderness reference site but evinced better conditions than the agricultural sites. A multiple-use (forestry, grazing, and wildlife management) watershed and the restored site ranked between the silvicultural and agricultural sites. This spectrum of land use and aquatic biointegrity illustrates both the challenges and opportunities that define watershed management.  相似文献   

18.
风能作为一种清洁无污染的可再生能源,已经被广泛运用到电力事业的发展中来。近年来,新疆的风力发电发展迅速,风电场建设过程中不可避免地会对土壤及植被造成一定的破坏,人为地加剧了水土流失。概述了风电项目水土流失特点,以新疆华电小草湖风电场工程为例,结合项目区具体特点,分区设置防治措施。通过工程措施、植物措施与临时措施的有机结合,有效地防止水土流失。  相似文献   

19.
A method is presented for calculating allowable use of tracked vehicles on the US Army's Pinon Canyon Maneuver Site in southeastern Colorado. The first step in this process is to determine the sheet and rill erosion rate on each soil series using the revised Universal Soil Loss Equation. Soil series are then ranked according to their trainability (e g., ranked based on how much vegetative cover can be lost without exceeding soil loss tolerance) Maximum onetime surface use, allowable surface use per year, usable hectares per year, and tracked vehicle days per year can then be calculated Examples are given to illustrate how these values can be manipulated to assist land managers and military trainers to better plan and match training missions to available land. Also, short- and long-term monitoring schemes are presented that can be used to verify or adjust estimates of allowable use. The methods presented can be converted to determine allowable use of other types of activities that disturb the vegetation and expose the soil surface to the erosive forces of wind and water (e g, recreational and off-road vehicles).  相似文献   

20.
ABSTRACT: Rainfall simulator studies were conducted during 1982 and 1983 on agricultural and native rangeland soils of the same soil series in northern Utah. Results indicate that the same soil series mapped at different locations on agricultural land will have similar 10, 20, and 30 minute infiltration rates and similar interrill erosion rates. Seasonal differences in infiltration and erosion rates were significant. Comparisons between agricultural and native soils were complicated by three-way statistical interactions. Seasonal variations in both infiltration rates and erosion rates were greatest on agricultural soils. Of four soil series on native rangeland, only one showed significant seasonal variation in infiltration rates, while erosion rates were similar across all seasons for all soil series. Soil and cover factors important in predicting infiltration and erosion were identified.  相似文献   

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