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1.
应用危险确认模型评估土地管理的可持续发展 总被引：4，自引：1，他引：4
New Zealand is highly dependent on its soil resource for continued agricultural production.To avoid depleting this resource,there is a need to identify soils and associated land management practices where there is a risk of soil degradation.Environmental integraity and ecosystem services also need to be maintoained.Accordingly,to ensure sustainable production,The on -and off-site environmental impacts of aldn management need to be identified and managed.We developed a structural vulnerability index for New Zealand soils.This index ranks solis according to their inherent susceptibility to physical degradation when used for agricultural (pasture,forestry and cropping) Purposes.We also developed a rule-based model to assess soil sompaction vulnerability by characterising the combined effects of resistance and resilience,Other soil attributes have been approatised using seven chemical,physical and biological indicators of soil quality.These indicators have been applied in a nation -wide project involving data collection from over 500 sites for a range of land uses.These soil quality data can be interpreted via the World Wide Web -through the in teractive decisionsupport tool SINDI,The land-use impact model is a framework to assess agricultural land management and environmental sustainability,and may be applied to land units at any scale.Using land resource data and information the model explicitly identifies hazards to land productivity and environmental integrity,It utilises qualitative expert and local knowledge and quantitative model-based evaluations to assess the potential environmental impacts of land-management pratices.The model is linked to a geographic information system(GIS),allowing model outputs.such at the environmental impacts of site-specific best management practices,to be identified in a spatially explicit manner,The model has been tested in New Zealand in an area of pastoral land use.Advantages of this risk identification model include:utilising current knowledege of the causes and effects of land-management practices on soil degradation;linking land management practice to both on-and off-site environmental consequences;identifying important gaps in local knowledge,and providing spatially explicit information on the environmental impact of land-management practices. 相似文献
2.
Abstract. When Albania emerged from its seclusion in 1991, the scientific community had its first opportunity to interact with its international counterparts. Soil resource assessment was made with systems developed in the early 1950s, laboratory facilities to provide supporting data were poor, and it was recognized that a new assessment was urgently needed. The country faces a major challenge in reforestation and soil conservation against a background of overgrazing by sheep and goats and clearing of trees and scrubs for fuelwood. Even orchard and olive trees were used as fuelwood during the winters of 1990 and 1991. Since then, gully and rill erosion has accelerated on many of the sloping lands. In addition to reforestation and conservation measures to reduce the pressures on the sloping land, it is necessary to enhance productivity on the fertile valley bottom soils where most of the agriculture is confined. In the recent past, grain yields have declined due to reduced fertilizer use (low purchasing capacity), and poor management practices. More recently productivity has slowly improved, but land degradation, particularly erosion, has visibly increased. USDA Natural Resources Conservation Service in collaboration with the Land Resources Institute of Albania, initiated work on a new national soil map through collation of existing information and field studies. The land unit for land use planning, evaluation, and general management decisions, is the Major Land Resource Area (MLRA). Each MLRA encompasses geographically associated soils, the majority of which have broadly similar patterns ofclimate, water resources, and land uses. The MLRAs presented here are based on the soil map of Albania at 1 : 200 000 scale. The MLRA information provides an overview of the landscape and natural resources. It can be used to assess land suitability for various crops, opportunities to achieve self sufficiency in food production, selection of areas for both field crops and highvalue crops for export, and identification of appropriate farming system technologies. Each MLRA will have a set of degradation processes which can be flagged, therefore each of them becomes a unit for decision making with respect to investments in research and mitigating technologies. The task is far from complete. Appropriate databases are needed to support the decisions that are being made at national level. To complement the MLRA and related database, decision support systems are needed for the important task of developing policy options. 相似文献
3.
Abstract. Information about the soil fertility status in irrigated ricelands at regional scales (1:50 000–1:250 000) is commonly not contained in classical soil maps. To assess the agronomic suitability of two different reconnaissance soil maps, we conducted a detailed soil survey in the Nueva Ecija province, Philippines. Soil samples were collected from 384 farmers' fields, and soil properties were measured for topsoil and subsoil samples. For most soil properties, a soil map made in 1940 (1:125 000) had within-map unit variances that were smaller than the total variance, whereas a new soil map of 1992 (1:50 000) did not significantly reduce the within-class variance. In both soil maps, classification into mapping units accounted for 0–40% of the variance of 14 agronomically important soil properties and large within-map unit variabilities were found. Underlying strategies of classical soil survey supported the partition of variance for relatively stable soil properties, such as soil texture, CEC, and organic matter. If reconnaissance soil maps are used in quantitative land evaluation studies, existing maps require upgrading by adding quantitative information about relevant soil properties and their within-map unit variability The sampling demand for upgrading a reconnaissance soil map was large, but pedotransfer functions can be used as cost-saving tools. Measures of soil nutrient status were highly variable within all mapping units and differences among farmers were much greater than the differences between soil types. Therefore, nutrient management in the study region should be based on individual field or farm recommendations rather than on soil-map based recommendations. 相似文献
4.
A soil map at the scale 1:10,000 serves as a major important document for land owners and local governments, which allows them to use soil information in their daily activity. The intensity of exploitation of soil maps will increase when the very map and its legend are supplemented, within colored and indexed polygons, with information about soil texture and reaction by layers, but also about the thickness and characterization of the epipedon, quality indices for soil assessment, classes of stoniness, and prevalent fractions of stones, erosion risk, etc. Special maps of agronomical status, with a list of proper measures for improvement of soils and their associations, should form a regular component of large‐scale mapping. As decrease in arable land and increase in the forest area are common trends in land use, these maps and general soil data should serve as the fundamental source of information for decision making concerning land use. Data indicating the suitability of any soil for any crop should be entered in a database. Application of GIS on any level of national economy, digitization of a large‐scale soil database and making it accessible to land users would allow to expand the amount of available information for each soil map polygon. 相似文献
5.
Abstract. A land evaluation at farm level was made for a toposequence of three New York soils, using the FAO framework and the LEACHN simulation model. The land utilization type (LUT) was continuous corn, using three varieties with different growing periods. Ten experts identified the same land qualities but three different types of land characteristics, as derived from soil survey data, field observations and simulation modelling. Differences could be explained by the backgrounds of the experts. A land evaluation procedure according to framework criteria using decision trees rather than matching tables was more accessible and transparent. Simulation of the soil-water regime provided quantitative data for all land qualities considered, and this procedure was preferred to qualitative estimates based on poorly defined procedures. When some land qualities cannot be characterized by simulation, however, a mix of qualitative and quantitative decision tree branches may be considered. The standard scheme of land evaluation, which is scale independent, provides irrelevant results at farm level because farmers' questions are different from those of regional planners who are well served by the traditional land evaluation procedure. For the farmer, development of decision support systems should be focused on optimal management decisions. 相似文献
6.
黄土丘陵区不同土地利用类型土壤水分时空变异特征 总被引：7，自引：0，他引：7
以黄土丘陵区的延河流域为研究区域,分析了3个时期（雨季前、雨季中、雨季后）不同土地利用类型对土壤水分动态的影响。结果表明：在水平层面、垂直剖面上土地利用类型对土壤水分动态有着显著的影响,农耕地土壤水分含量最高,并且对土壤水分含量影响最为明显,使其保持在一个较高的水平;其次是天然草地、撂荒地、乔木林地、果园用地和幼林地;含量最低的为灌木林地。在垂直剖面上,雨季前干旱期为递增型;雨季中湿润期为递减型和波动型;雨季后半湿润期为先减后增型。从总体趋势上来看,土壤水分的时空格局与降雨季节变化、植物蒸腾作用以及土地耕作利用方式密切相关。在延河流域,土地利用方式对土壤水分在不同的季节都具有显著性的影响。在该流域的管理中,应充分考虑不同土地利用类型对土壤水分的影响,优化土地利用结构,使流域的治理达到最优。 相似文献
7.
8.
A principal challenge in erosion control is the integration of the many technical and non‐technical issues that affect the acceptance of soil conservation measures by land users. This first paper in a three‐part series considers the main criteria at farm level: biophysical efficiency; productivity and sustainability; and socio‐economic acceptability. A model is developed to integrate these various components into a decision‐making framework for soil conservation at the farm level. With the particular conditions of the Loess Plateau in China, land degradation comprises a number of key biophysical and socio‐economic variables. The model components therefore include available water storage capacity of the soil as an index of productivity, the organic matter and mineral soil balance to reflect the major changes to the soil when eroded, and cost‐benefit analysis to determine the economic wisdom of devoting household resources to land improvement. The model is calibrated using data from the Nihegou Catchment near Chunhua in the southern part of the Loess Plateau. Through simulation runs, this model enables a better understanding of erosion–productivity–time relationships. Although relatively simple, the model successfully encompasses the processes of greatest significance to agricultural development in this part of China. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
9.
《Land Degradation \u0026amp; Development》2017,28(8):2513-2526
Soil sealing is considered among the most dangerous of land degradation processes on global, European and national scales. Despite important policy documents aiming to mitigate this soil threat, it currently shows no signs of abating, and current efforts often do not result in appropriate implementation of soil sealing mitigation in spatial planning, which represents the subject area governing soil sealing. In this paper, we show a spatial decision support system – based on a Geospatial Cyberinfrastructure – with the aim of applying it as an operational instrument aiming towards soil sealing mitigation. The system has the ambition to impact on those who take decision over soil sealing; typically, these are not agriculture experts but rather spatial planners. This tool, focusing on mitigating such crucial land degradation, allows the users – via the Web – to produce ‘what‐if’ land planning scenarios thanks to the ‘on‐the‐fly’ modelling engines. Therefore, integrated geospatial quantitative data and procedures may be directly and freely used by planners. The tool has been applied to and tested in an area in the South of Italy. Results from two applications are reported: one addressing municipal planning and the other on a more detailed spatial scale. Furthermore, results include quantification of rural fragmentation, loss of soil ecosystem services and an estimate of soil sealing evolution over time. The tool was developed with the help of end users and indirectly explores a change of paradigm where soil science and landscape/urban planning work together to provide operational instruments that may be adopted by local communities in addressing soil sealing issues with a proactive approach. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
10.
C. A. Igwe 《Land Degradation \u0026amp; Development》1999,10(5):425-434
In areas susceptible to erosion, there is the need for a comprehensive soil conservation programme so as to be able to prevent catastrophic soil erosion problems. The absence of such a programme in central eastern Nigeria, that has a total land area of 20 000 km2, necessitated the drawing up of a soil conservation strategy for the area. The aim was to provide information for better land-use planning and proper environmental and soil management. To achieve this, topographic, soil and landform maps of the area at the scale of 1:50 000 were used to delineate into slope land units, viz: 0–4 per cent, <4 per cent, drainage basins and headwaters. These slope units and estimated soil erosion hazard units using the revised universal soil loss equation (RUSLE) were employed to form a general purpose land classification based on the USDA land capability classification and FAO framework on land evaluation.The soil loss tolerance of the area falls between 1·16 and 1·30 Mg ha−1 yr−1, while the erosion hazard units are considered generally suitable for the various land utilization types, with a number of limitations the main ones being erosion and waterlogging. The soil conservation measures proposed involved the application of bioenvironmental processes in the area and appropriate watershed management. The techniques proposed are those based on low input technology, affordable by rural farmers. It is concluded that these soil conservation measures will be adequate for sustainable agricultural production in the area. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
11.
中国土壤侵蚀影响因素及其危害分析 总被引：37，自引：4，他引：33
该文从降雨、地貌、植被、土壤及人为因素等方面对中国土壤侵蚀的影响因素进行了系统分析,研究了土壤侵蚀使中国土地资源破坏、粮食减产、灾害发生、土壤肥力下降、水资源环境污染、库塘湖泊淤积、城市安全受到威胁等一系列危害,可供水土保持及环境整治决策作参考 相似文献
12.
The soil environmental index(SEI),which is a four digit code system,represents relatively homogenous spatial unit with specific soil capacity to provide ecological or non-production functions.This work aimed to present information on rating and economic evaluation of SEI,which is a spatial identifier used for expressing heterogeneity of Slovak agricultural soil to support analysis of soil ecological functions.In this study,SEI index expressed the capacity of soil to accumulate water,immobilise the risk elements and substances and transform risk substances(organic pollutants).Partial evaluations of soil capacity to provide above mentioned functions were used to derive final SEI values.Within the agricultural soils of Slovakia there were 493 combinations of soil environmental index.Each index was expressed through rating(point)value and economic value.Average value of Slovak agricultural land to provide selected ecological soil functions was 55.3 points,which corresponded to 35.946 billionper agricultural land or approximately 1.42per square meter.Spatial identification of SEI codes and relevant database were developed in vector form via geographical information systems of Soil Science and Conservation Research Institute,Bratislava.In addition to using the national soil database system,a strategy was presented for evaluating and pricing of soil ecological function,and the development of an soil environmental index.Assessment and evaluation of vitally important soil functions expressed by SEI can significantly contribute to planning and protection of the soil,and can regulate indiscriminate anthropic interventions in land use decisions. 相似文献
13.
不同比例尺数字高程模型在水土保持信息提取中的应用分析 总被引：5，自引：3，他引：5
在ARCGIS软件支持下 ,基于不同比例尺的DEM提取坡度信息 ,与土地利用类型、植被覆盖度和土壤侵蚀强度等专题信息叠置 ,提取水土保持专题信息 ,并对提取结果进行应用分析。研究结果表明 ,1∶1万比例尺的DEM可在小流域规划设计、水土流失监测、信息系统建设等工作中应用 ,1∶5万比例尺的DEM可用在重点支流、重点治理区 (片 )等尺度上的三维可视化系统建立、水土保持规划等 ,1∶2 5万比例尺的DEM只能在较大区域中进行宏观信息提取时使用。 相似文献
15.
P. B. S. Hart A. W. West J. A. Kings H. M. Watts J. C. Howe 《Land Degradation \u0026amp; Development》1999,10(5):435-453
A three-year field trial on an upland loessial soil (Belmont silt loam) in New Zealand investigated the effects of ripping, application of fertilizer N and grazing management on the recovery of some physical, chemical and biochemical properties of soil and pasture productivity following removal (mining) of topsoil. Removing the top 31 cm of soil by mining (all of the A horizon and part of the AB horizon) also removed most of the soil's labile organic matter fractions, and to a lesser extent its total organic matter. After three years, the microbial C and mineralizable N in the 0–10 cm depth of mined soil had reached 65 and 62 per cent of the corresponding levels in unmined soil. Ripping to a depth of 30 cm, application of fertilizer N and lenient grazing of the pasture failed to enhance the recovery of soil fertility. A soil sampling depth of 20 cm provided a reasonable basis to assess the microbial biomass and potential fertility. Pasture productivity was, on average, 30 per cent lower on mined land than on unmined land over the first three years after mining. Application of N proved uneconomic in terms of farm production, although a good pasture response to N fertilizer was obtained. The results from this and related trials are summarized as a series of recommendations for the monitoring and regulation of topsoil mining. An incentive regime is also recommended to encourage land owners and/or topsoil miners to use successful restoration techniques on topsoil-mined land. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
16.
The use of land evaluation information by land use planners and decision-makers: a case study in Santa Catarina, Brazil 总被引：1，自引：0，他引：1
Abstract. Land evaluation is the prediction of land performance over time under specific uses, to guide strategic land use decisions. Modern land evaluation has a 30 year history, yet the results have often been disappointing. Land users and planners have been reported to ignore land evaluations, perhaps reflecting poor quality, low relevance, or poor communication. To test the success of a large land evaluation exercise undertaken as part of micro-catchment project in Santa Catarina State, southern Brazil, we queried agricultural extensionists, considered as the primary land evaluation clients. We used a questionnaire with both structured and open questions, to determine their experiences with, and attitudes to, the current land evaluation method. The soil resource inventory and associated land evaluation had some usefulness, but were not in general used for their intended purpose, namely farm planning. This was mainly because they did not contain crucial information necessary to such planning in the actual context of the farmer taking decisions. The primary deficiencies were identified as:
- (1)
no estimate of environmental degradation risk;
17.
"退耕还林"政策驱动下的农户土地转用决策及其土地利用变化影响研究——基于江西省丰城市农户问卷调查的一个分析 总被引：4，自引：0，他引：4
在分析“退耕还林”政策驱动下的农户土地转用决策机理的基础上,以江西丰城市的农户调查资料建立了“退耕还林”政策与农户土地利用变化的计量分析模型,结果表明:(1)退耕收益补偿对比值对土地利用变化有显著的影响;(2)“退耕还林”政策中对土地产权的安排对土地利用变化强度影响不大;(3)在不同区域,土地利用变化强度的影响因素不同,土地资源丰度、农户择业行为对土地利用变化强度影响较大。并进一步就推进生态友好的土地利用方式、合理引导土地利用变化提出了相关建议。 相似文献
18.
H. E. Dregne 《Land Degradation \u0026amp; Development》1995,6(2):71-78
Soil erosion assumes a different form in Australia and New Zealand. Sheet, rill and gully erosion are common in eastern Australia and wind erosion in the dry cropland areas. In New Zealand, mass movement dominates the erosion landscape but other kinds, including wind erosion, do occur. It is unclear how much of the mass movement is a natural phenomenon and how much is human-induced. In either case, it causes long-term reductions in soil productivity. A landmark analysis of the soil productivity loss due to land degradation was conducted by the Australian state of New South Wales. Water erosion was a greater problem than wind erosion, but soil structure deterioration was more costly than either kind of erosion. 相似文献
19.
为揭示不同农地产权情况与农户水土保持行为响应的差别,探讨了农地产权中,各个要素对农户水土保持行为的影响,构建了农地产权与农户水土保持行为响应相互关系的逻辑模型,并根据农户调查数据,应用极大似然估计法,对该模型进行了估计。农地产权与农户水土保持决策逻辑模型的运行结果表明:在行政村内转包的权利、抵押权、有无土地租赁、农户对水土流失的感知、不同的地区对农户的水土保持决策有明显的影响。 相似文献
20.
云蒙湖流域不同土地利用类型的土壤侵蚀特征分析 总被引：2，自引：0，他引：2
在RS与GIS支持下,获取云蒙湖流域土地利用空间数据,选用RUSLE模型估算土壤侵蚀量,对云蒙湖流域不同土地利用类型的土壤侵蚀特征进行分析。结果表明:1986—2010年间,土壤年总侵蚀量由647万t降至630万t,水土保持生态恢复工程取得了一定的成效;云蒙湖流域耕地土壤侵蚀最为严重,1986年和2010年土壤侵蚀模数高达5 325t/(km2·a)和5 504t/(km2·a),分别占土壤侵蚀总量的85.8%和84.7%;草地是重点治理的另一对象,强度以上等级侵蚀都分别占总侵蚀面积的40%和44%;随着耕地和草地类型的转入,居民用地侵蚀面积由1986年的1 010hm2增至2010年的2 608hm2,土壤侵蚀总量由5.4万t增至14.2万t,是变化较为明显的土地利用类型。 相似文献