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1.
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   

2.
基于土地利用视角的土地利用总体规划质量分析   总被引:1,自引:0,他引:1  
土地利用总体规划是一项全局性和战略性的工作, 其质量好坏, 不仅关系着土地资源能否得到合理利用, 还关系着经济社会的可持续发展。本研究从土地利用视角出发, 建立了土地利用与规划效果之间的经验联系, 提出由土地利用形态、土地利用结构、土地利用行为、土地利用程度、土地利用功能和土地利用布局6方面内容所组成的分析体系。在此基础上综合评价规划质量, 并以四川省乐山市金口河区为例, 对其新近编制完成的县级土地利用总体规划质量进行了评判。结果表明, 该规划的质量等级为优, 符合土地利用目标要求, 能够促进区域土地资源的优化配置。本研究旨在利用此种方法, 为土地利用总体规划管理实践提供一定的方法支撑, 切实提高规划的编制质量和实施效果。  相似文献   

3.
本文从主体功能区战略角度出发,构建了适用于土地利用总体规划中新增建设用地指标分配的主体功能区划分指标体系,以河北省卢龙县为例,得出该县主体功能区划结果。并结合区域土地利用及土地开发、利用、整治、保护(DUHP)优先度的组合模式,计算在新一轮土地利用总体规划中卢龙县分配到各乡镇的新增建设用地指标。其中刘田各庄镇、卢龙镇和石门镇3个乡镇作为卢龙县优先开发区和重点开发区,分配到的新增建设用地指标最多,均达到230 hm2以上;其他乡镇在保证重点城区发展的基础上,也获得一定数量的指标。本文旨在利用此种方法,为土地利用总体规划的指标分配提供一定的方法支撑,促进规划范围内土地资源优化配置,保证土地资源的可持续利用。  相似文献   

4.
Economic land evaluation: why and how   总被引:3,自引:0,他引:3  
Abstract. Economic land evaluation is a method for predicting the micro-economic value of implementing a given land-use system on a given land area. This is a more useful prediction of land performance than a purely physical evaluation, since many land-use decisions are made on the basis of economic value. Measures of economic suitability include the gross margin, net present value, internal rate of return, benefit:cost ratio, and utility functions based on these. The economic value of the in-situ resource quality of a land area may be inferred directly from land characteristics or from Land Qualities which, when less than optimum, result in decreased yields or increased costs. The economic value of geographic land characteristics may be determined by spatial analysis. Single or multi-criteria economic optimization and risk analysis can extend the economic land evaluation from a natural resource or management unit to a production or planning unit. Computerized tools may be used to assist in economic land evaluation.  相似文献   

5.
Abstract. Good land management needs information about land resources and the processes taking place in the landscape. In practical land evaluation this information is often expressed in terms of land qualities. The original survey data are stored in geographical information systems where they can be used to estimate the values of appropriate land qualities. Land qualities are complex attributes of land used in planning that may be derived from the original attributes through empirical threshold or regression models, or from process-based deterministic or stochastic simulation models. In order to improve estimates of the distribution of land qualities in space and time, and hence to improve planning decisions, the models require data with a much better spatial resolution than is usually available. The problems and dangers associated with the ad hoc linkage of simulation models and GIS are discussed. Particular attention needs to be paid to the problems of error propagation and costs and benefits when using models.  相似文献   

6.
区域土地利用结构的碳效应评估及低碳优化   总被引:10,自引:3,他引:10  
区域土地利用是引起碳排放的重要因素,土地利用结构优化能在一定程度改变土地利用的碳源/汇格局,并引导区域经济社会的低碳发展。基于线性规划方法,该文建立了区域土地利用碳效应综合评估及优化调控的方法,并以南京市为例,提出了3种土地利用低碳优化方案,并对其碳减排潜力进行了对比分析及蒙特卡洛模拟,最后提出了低碳土地利用优化的政策建议。结果发现,2020年南京市土地利用总体规划方案使区域的总碳蓄积量有所提升,但预期碳排放远远大于碳蓄积的增加值,同时也将会导致生态系统碳汇能力的降低;在3种优化方案中,基于碳排放最小化的土地利用结构优化方案比2020年规划方案的碳排放减少了73.75万 t,碳减排潜力为8.50%,表明该方案起到了较好的预期减排效果;因此,该文建议将基于碳排放最小化的土地利用结构优化方案作为南京市未来土地结构调整和产业规划的参考,该方案不仅有助于实现碳减排的目标,而且对于控制建设用地的过快增长、增加生产性土地面积、引导农地整理和居民点用地整理等土地利用规划和开发活动都具有重要的现实意义。  相似文献   

7.
Abstract. In the European Community (EC) a change towards more market-oriented land use planning is required because of surplus stocks of cereals and dairy products, while at the same time other agricultural goods have to be imported. The implementation of such a policy has to be based on a scientifically sound and objective inventory of the physical potential of the EC as a whole.
Principles of such a physical land assessment are explained, using the concepts of the FAO-Framework for Land Evaluation and the Agro-ecological Zone Approach, but adapted to European conditions. The conclusions arrived at through this procedure lead to different alternatives and scenarios, and hence provide valuable background information for future land use planning.  相似文献   

8.
Land evaluation is a critical step in land‐use planning. Although many methods have been developed since the formulation of the FAO framework for land evaluation, several of the more traditional approaches still remain in widespread use but have not been adequately evaluated. Contrary to more recent land evaluation systems, which need considerable data, these systems only require basic soil and landscape information to provide a general view of land suitability for major types of land use. As the FAO initially presented its qualitative framework for land‐use planning, based on two previous methods developed in Iran and Brazil, in this study we assessed the reliability and accuracy of a traditional land evaluation method used in Iran, called land classification for irrigation (LCI), comparing its results with several qualitative and quantitative methods and actual yield values. The results showed that, although simpler than more recently developed methods, LCI provided reliable land suitability classes and also showed good relationships both with other methods analysed and with actual yields. Comparisons between qualitative and quantitative methods produced similar results for common crops (a barley–alfalfa–wheat–fallow rotation). However, these methods performed differently for opportunist crops (such as alfalfa) that are more dependent on income and market conditions than on land characteristics. In this work, we also suggest that using the FAO method to indicate LCI subclasses could help users or managers to recognize limitations for land‐use planning.  相似文献   

9.

Purpose

Land preparation (e.g., leveled ditches, leveled benches, adversely graded tableland, and fish-scale pits) is one of the most effective ecological engineering practices to reduce water erosion in the Loess Plateau, China. Land preparation greatly affects soil physicochemical properties. This study investigated the influence of different land preparation techniques during vegetation restoration on soil conditions, which remained poorly understood to date.

Materials and methods

Soil samples were collected from depths of 0–10, 10–20, 20–40, 40–60, 60–80, and 80–100 cm, in the typical hilly watershed of Dingxi City, Loess Plateau. Soil bulk density (BD), soil organic matter (SOM), and total nitrogen (TN) were determined for different land preparations and vegetation type combinations. Fractal theory was used to analyze soil particle size distribution (PSD).

Results and discussion

(1) The effect of land preparation on soil properties and PSD varied with soil depth. For each land preparation category, SOM and TN values showed a significant difference between the top soil layer and the underlying soil depths. (2) The fractal dimension of PSD showed a significant positive correlation with clay and silt content, but a significant negative correlation with sand content. (3) The 20 cm soil layer was a boundary that distinguished the explanatory factors, with land preparation and vegetation type as the controlling factors in the 0–20- and 20–100-cm soil layers, respectively.

Conclusions

Land preparation and vegetation type significantly influenced soil properties, with 20 cm soil depth being the boundary for these two factors. This study provided a foundation for developing techniques for vegetation restoration in water-limited ecosystems.
  相似文献   

10.

Purpose

Disturbances such as cultivation, logging, and plantation occurred widely in acid red soil area of China, yet little is known about their effects on soil microbial community which is closely related to soil function. In this study, microbial community compositions were investigated in a red soil with different long-term land utilization patterns to understand the potential effects of cultivation and vegetation successions on relevant soil functions.

Materials and methods

Land utilization patterns include restoration, degradation (logging), cropland, and pine plantation. Both DNA- and phospholipid fatty acid (PLFA)-based methods were used to measure the abundance and community structure of microorganisms.

Results and discussion

In general, DNA- and PLFA-based methods showed similar results of microbial composition, but for some parameters, only one approach showed significant differences between different land utilization patterns. Land utilization patterns showed significant effects on abundance of total microbial community, bacteria, fungi, and actinomycetes which were all lowest in the cropland plot either by PLFA or DNA analyses. 17:0 cyclo/16:1 ω7c and 19:0 cyclo/18:1 ω7c which are possibly associated with environmental stresses also varied among different land utilization patterns. Both PLFA and T-RFLP analyses showed that each land utilization pattern possessed a specific microbial community structure.

Conclusions

These results revealed significant effects of different land utilization patterns especially cultivation and logging on soil microbial communities and suggested that we should be cautious in utilizing red soils to sustain soil properties and functions. Combination of DNA- and PLFA-based methods is effective to provide precise results of microbial composition.  相似文献   

11.
近10 a黄河三角洲LUCC及其驱动因素分析   总被引:5,自引:2,他引:3  
研究滨海脆弱生态区的土地利用/土地覆被时空变化过程,可以为区域土地资源的规划、开发和管理提供科学依据。该文应用遥感和GIS技术,分析黄河三角洲区域1995-2004年间土地利用/土地覆被的时空变化特征,并对区域土地利用/土地覆被变化的驱动因子进行了探讨。结果表明,近10 a来黄河三角洲的土地利用/土地覆被类型发生了复杂变化;黄河三角洲土地利用/土地覆被动态受到自然因素和人类活动的共同作用,而人类活动是近10 a区域土地利用/土地覆被变化的主要驱动因子。尽管近年来黄河三角洲的开发取得了快速发展,但部分人类经济活动给区域土地资源及其生态环境的可持续发展带来巨大压力,甚至导致区域土地质量的进一步退化。  相似文献   

12.
矿业城市土地损毁生态风险评价与空间防范策略   总被引:5,自引:3,他引:2  
常青  刘丹  刘晓文 《农业工程学报》2013,29(20):245-254
为量化矿业城市土地损毁生态风险、提高土地复垦和综合整治有效性,以吉林省辽源市为研究区,提出基于GIS的矿业城市土地损毁生态风险定量评价与空间防范的思路和方法。首先将土地损毁作为直接生态风险源,将土地生态系统作为生态风险受体,借助遥感信息模型与GIS空间分析模型,依次评价土地生态系统的生态敏感性、土地损毁累积作用以及二者间的暴露关系;然后确定综合生态风险值及其等级空间分布,并据此将矿业城市土地利用划分为环境敏感特别保护区、一般生态保护区、生态保育区、生态协调区、生态复垦区、限制发展区、工矿发展区与城镇发展区等八大功能区,各区内生态风险防范措施各有侧重;最后利用2010年城市总体规划图对评价与分区结果进行有效性分析,分析结果表明,辽源市90%以上的规划建设用地属于发展主导区域、70%以上的非规划用地属于生态保护主导区,研究结果与2010年城市规划用地布局范围基本吻合。基于 GIS 定量方法进行矿业城市土地损毁生态风险分析可空间化土地利用的风险等级与主导风险因素,为制定有针对性的风险防范措施提供了空间信息;也为矿业城市土地复垦规划、土地整理规划与土地利用总体规划的有机结合提供了参考。  相似文献   

13.
The inclusion of ecological information in land use planning decisions is now mostly accepted but there still remains considerable confusion as to how such information can be assessed, organised and incorporated in the land use planning process. This paper suggests a framework that may be of use in such deliberations. The main components of this framework are ecological evaluations and threshold evaluations and some discussion is directed at how these might be assessed, drawing upon previous research in these areas. Finally some suggestions are made as to how the results of such evaluations might be incorporated into land use decisions.  相似文献   

14.
基于蚁群算法的洱海流域土地利用变化模拟   总被引:1,自引:1,他引:0  
为了研究社会经济和城市化快速发展作用下的洱海流域土地利用/覆被变化过程,以促进流域用地结构与配置的优化。基于智能体建模理论,结合GIS的数据处理和空间分析技术,利用蚁群智能算法模拟土地利用变化。针对洱海流域的现状,该文选取流域土地利用变化的影响因子,建立了智能体分类体系及其行为决策规则;基于Java语言和Repast J建模平台,完成了模型的程序设计、实现、模拟过程;针对模型的模拟结果进行了分析和验证。结果表明:蚁群算法提升了智能体模型模拟结果的精度,且基本与实际情况的空间格局保持一致。基于模拟结果分析了未来10 a(2010-2020年)洱海流域的人地关系矛盾主要表现为农业生产性用地(耕地和园地)的持续性减少与建设用地的不断增长,现有政策下的城镇化用地成本呈上升趋势。而生态用地中,湿地的增长最快,表明政府的用地规划和策略对流域的生态用地保护起到较好的宏观调控作用。  相似文献   

15.

Purpose

The complex and multi-functional body of soil is crucial for land use; therefore, soil evaluation should guide land-use planning. In regard to this, there is an urgent need for function-based soil evaluation, especially in highly developed and fast-growing countries. In China, there is no specified law which may protect soil comprehensively, and due to ignorance of certain soil functions, soil evaluation has not played a prominent role in land-use planning. In addition, soil evaluation must be brought into the practices of land-use planning in China to facilitate rational and sustainable land use.

Materials and methods

In this study, by analyzing the evidence of soil functions and the according algorithms for soil evaluation, the necessity and possibility of combining function-based soil evaluation and land-use planning are found. For this, existing application studies from China and Europe were used. Using the methods of TUSEC (Technique for Soil Evaluation and Categorization for Natural and Anthropogenic Soils), the results of function-based soil evaluation of Zhengzhou City are shown, and tentative suggestions for land-use planning are given. Through the summarization of the previous discussion and a case study of Zhengzhou City, the future possibilities and perspectives for soil evaluation in land-use planning in China are determined.

Results and discussion

At present, China's focus in soil evaluation is on agriculture; thus, a lack of attention toward ecological balances in the environment has been found. In order to satisfy the reasonable planning of different land uses, a function-based framework of soil evaluation is required. TUSEC was found to be a suitable model for the evaluation method of soil functions, which China could adopt in its land-use planning. Function-based soil evaluation is necessary to improve land-use database and mapping to guide overall land-use planning, to optimize local ecological adjustment, and to monitor ecological sensitive areas.

Conclusions

As the awareness of sustainable development grows, the role of soil evaluation in the procedure of land-use planning is becoming increasingly important in China. A function-based soil evaluation may be adapted to this necessity.  相似文献   

16.
耕地后备资源是耕地的重要补充来源,在耕地占补平衡中具有重要作用,但在补充耕地能力上长期存在偏主观、重数量等情况。利用国土部新一轮耕地后备资源调查评价试点县成果,在新增耕地系数和等级折算系数的基础上提出了耕地数量与耕地数量质量并重的平衡测算方法,分析县域规划期内实现耕地占补平衡的能力。以湖南省沅江市为例,测算至2020年实现数量平衡和数量质量平衡需开发的耕地后备资源面积。结果显示,满足耕地数量平衡需开发耕地后备资源面积为1 083.37 hm2;满足数量质量并重平衡,最低需开发耕地后备资源面积1 083.37 hm2,最高需开发1 351.65 hm2。通过测算,沅江市耕地后备资源开发可满足县域耕地占补数量、质量平衡的需要,但存在较大压力,尤以数量质量并重平衡为甚。因此,明晰县域耕地后备资源补充耕地的能力有利于合理安排新增建设项目,确保实现土地利用总体规划保护耕地的目标。  相似文献   

17.
基于土地开发整理修订农用地分等结果的一种方法   总被引:8,自引:6,他引:2  
土地开发整理是实现耕地占补平衡的重要手段,补充耕地质量问题也一直是耕地占补平衡工作中的薄弱环节。针对补充耕地质量问题,以及已取得的农用地分等成果,考虑土地利用数据共享的原则,对在土地开发整理项目耕地等级评定中如何充分和合理利用农用地分等成果进行探讨,即对土地开发整理项目的耕地等级评定过程中,把土地开发整理工程作用的因素作为补充指标对耕地等级指数进行修订。在充分考虑补充耕地质量的基础上,依据土地开发整理工程内涵,建立了适宜土地开发整理项目中耕地等级评定的一种技术方法。并通过大石桥市虎庄镇土地开发整理项目的实证,取得令人满意的效果。  相似文献   

18.
黑龙江省土地整治规划效益分析与评价   总被引:8,自引:4,他引:4  
土地整治规划效益分析评价是土地整治规划重要的组成部分。该文在界定土地整治规划效益分析评价概念的基础上,运用层次分析法建立了"国家目标层——专项目标层——指标层"3级土地整治规划效益分析评价指标体系,采用统计预测方法、类比分析法和专家调查方法,对黑龙江省土地整治规划(2011-2020年)的效益进行了分析和评价。结果表明:黑龙江省土地整治规划在保红线、保发展,落实最严格的耕地保护制度和最严格的节约用地制度,促进社会主义新农村建设和统筹城乡发展方面,具有极其显著的综合效应;统计预测、类比分析和专家调查3种方法可以结合起来,用于规划的效益分析;该文的研究思路和方法可以为其它学者研究区域土地整治规划效益提供依据。  相似文献   

19.
利用马尔柯夫过程预测蒙阴县土地利用/覆被格局变化   总被引:2,自引:0,他引:2  
常成  刘霞  张光灿  姚孝友  张荣华  张荣 《土壤》2010,42(2):309-313
为了解蒙阴县土地利用/覆被的变化规律及其未来变化,由蒙阴县1997年和2007年2个时期的遥感图像获得的土地利用/覆被数据,确定土地利用/覆被的初始状态矩阵和转移概率矩阵,据此用马尔柯夫模型对研究区的土地利用/覆被格局的未来变化趋势进行了预测。结果表明:蒙阴县土地利用/覆被格局正处在一种变化状态,耕地、草地、水域及水利设施用地、未利用地面积在今后一段时期内仍呈减少趋势,到2017年耕地面积比例较2007年减少3.22%,林地、城镇村及工矿交通用地仍呈增加趋势,其中以林地增长幅度较大,到2017年其占比将达到43.45%。根据模拟结果可调整各类土地利用/覆被格局,为宏观决策提供科学依据。  相似文献   

20.
大都市郊区土地利用时空演变特征与生境质量评价   总被引:2,自引:2,他引:0  
为探究大都市郊区"土地利用-生境质量"可持续机制,以天津市郊区武清区为例,通过分析1980—2018年的土地利用数据,以In VEST模型对其进行Habitat Quality模块水平数值测度,研究京津都市圈发展对大都市郊区土地利用转型与生境质量的影响。研究结果:1)1980—2018年武清区土地利用类型以耕地为主导,但耕地面积下降明显,城镇用地和农村居民点用地面积快速增长,未利用地面积大幅缩减,林地和草地占比较小。2)武清区土地利用类型转换剧烈,耕地转移面积最大,林地和草地集中向城镇用地和农村居民点用地转移,水域集中转向耕地,城镇用地和农村居民点用地转移面积较大,未利用地转换面积较小,但转移概率最为剧烈。3)武清区土地利用综合动态度增长了2.87%,具体表现为城镇用地、农村居民点用地和水域的土地利用变化速率保持正向增长,耕地变化速率呈现负增长。4)总体上,武清区呈现出"城扩耕缩"、"人进草退"的态势,但局部年份也有"草进水进"的转态;武清区生境质量处于中等级,但中等级面积趋于下降,低等级生境质量面积趋于上升,较低等级面积较小且呈下降趋势,较高和高等级生境质量区面积趋于扩大;生境质量低值区以武清城区为核心集中分布,且零星分布于武清区东北、西北地区;生境质量高值区集中分布于武清区东部。研究表明:在我国推进新型城镇化发展,特别是加强跨区域都市圈建设中,应当严格保护大都市郊区生态源地,统筹调控大都市郊区生态安全分区,推进大都市郊区生态廊道和全域生态节点建设。  相似文献   

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