ISSN:0266-0032    

DOI:10.1111/j.1475-2743.1989.tb00752.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

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 thead hoclinkage 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 model

ISSN:0266-0032    

DOI:10.1111/j.1475-2743.1989.tb00753.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract.Land evaluation involves the definition of the comparative marginal value of individual land areas for the uses being considered. For agricultural land evaluation crop yields are the most reliable estimates of comparative marginal values. Yield values can be obtained from field measurements, as well as from productivity indices and empirical and mechanistic crop growth models. This paper reviews the pros and cons of each approach. Mechanistic models of the summary type, that simulate only those processes that are critical to describe an agroecosystem, are the most realistic and practical tools for land evaluation. Criteria for these types of models are given.

ISSN:0266-0032    

DOI:10.1111/j.1475-2743.1989.tb00754.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract.The WOFOST simulation model is a tool for analysing the growth and production of field crops under a wide range of weather and soil conditions. Such an analysis is important first to assess to what extent crop production is limited by the factors of light, moisture and macro‐nutrients, and second to estimate what improvements are possible. The theoretical concept of a production situation, as modelled by WOFOST, is explained, as is the hierarchy of potential production and water‐limited and nutrient‐limited production situations in the analysis. The organization of the computer files in the model, the structure of the FORTRAN source program and the available standard sets of data are described br

ISSN:0266-0032    

DOI:10.1111/j.1475-2743.1989.tb00755.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract.Assuming that other sources of error can be neglected, the reliability of a land suitability classification depends on the homogeneity of physiographically delineated map units with regard to land qualities. The map unit homogeneity of a small area in France was estimated using 64 observation points, arranged according to a nested sampling scheme, followed by nested analysis of variance.The analysis shows that in this area map units are too heterogeneous to accept the suitability classification as being completely reliable. However, alternative procedures using methods of optimal interpolation to map gradual change within the physiographic units are too expensive at a mapping scale of 1:25000 or smaller. It is not possible to produce completely accurate suitability maps at smaller scales. However, incorporating nested sampling and analysis of variance as standard procedures in land evaluation surveys costs little effort and yields at least an estimate of map accuracy and reliability of the suitability classification.

ISSN:0266-0032    

DOI:10.1111/j.1475-2743.1989.tb00756.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract.The ultimate goal of resource monitoring is to analyse the spatial distribution of the balance between supply and demand of a certain resource. Remote sensing techniques are commonly used for the assessment of thesupplyof resources. By integrating remote sensing with the related techniques of geographical information systems and spatial modelling, thedemandas well as theaccessibilityof resources can be analysed. The article gives an overview over methods for integrated resource monitoring. Examples from arid environments are also presented.

ISSN:0266-0032    

DOI:10.1111/j.1475-2743.1989.tb00757.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract.Since 1981 information on land sales has been recorded in the Land Register for some counties in Scotland. Rural land sale data for areas of more than 10 hectares in Renfrewshire have been analysed to determine the extent to which land capability, elevation and slope have an influence on land value. Although many factors influence the price paid for rural land, the effect of land capability in particular is demonstrated, with altitude having a minor effect. Using a best fit curvilinear model price ranges are predicted on the basis of land capability classes.

ISSN:0266-0032    

DOI:10.1111/j.1475-2743.1989.tb00758.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY