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Along with the development of the starch and grain-alcohol industries, biomass energy production has recently become important. Cassava is an important biomass energy plant. In this paper, geographic information system (GIS) and remote sensing (RS) are used, along with a knowledge of the growing environment needed for cassava and the farmland and ecology protection policy of China, to evaluate the cassava growing potential of Wuming County. The processing of spatial data is done first. Then, the evaluation principles are defined according to the spatial data and the required growth conditions. The evaluation data are obtained by spatial data analysis according with the evaluation principles. Lastly, the cassava planting potential results are verified by referencing these to cassava planting statistical data for 2005 provided by Nanning City Government of Guangxi province. This paper provides the science basis for Wuming County to develop local grain-alcohol and biomass energy industries. [ABSTRACT FROM AUTHOR]

This paper applies the spatial-temporal data model to describe geographical information changes among field parcels. A field parcel is a representative geographical element of farmland. It is the fundamental element in agricultural production in which crop planning, crop management and crop evaluation are carried out. Field parcels are the object of study in this paper. The spatial-temporal characteristics of field parcel geographical information are analysed into graph-based, spatial-temporal data models and are applied to the Field Parcel Up-dating Geographical Information System(FPUGIS), a system used to store update information. This new method is a vast improvement on the old system due to its simple and integrated data structure. [ABSTRACT FROM AUTHOR]

This paper describes a decision support system (DSS) for evaluation of the ecological benefits of rehabilitation of coal mine waste areas. The system was used as a tool to evaluate the ecological benefits; it supported users to select the proper models and index systems according to the waste type or the users' predilection. The DSS was applied in the Fuxin coal mine dump area. Our novel integrated web-GIS DSS was implemented using a web server and ServletExec technology over an ArclMS plat form to support data access and processing in a distributed environment. The DSS allows the generation and evaluation of suitable alternatives with respect to salient features of the problem, especially environmental consequences. The paper describes the identification and collection of relevant information, the structure of a database, the design of algorithms for solving the core location problem, the study of models for evaluating the different alternatives and their framing in a complete multicriteria decision model. In particular, the model management subsystem supports the user to choose a corresponding algorithm and modify the index for ecological benefits. Finally, the solution of the case study, by means of the DSS, is described. [ABSTRACT FROM AUTHOR]

Agricultural land use in suburban Beijing has changed dramatically in the last decade. This paper utilised unique, county-level spatial inventory datasets of land use in 1993 and 2004 to better quantify spatial configuration changes of main agricultural land-use types in the suburban counties of Beijing. A revised centroid model was applied to explicitly capture, analyse and visualise centroidal coordinates of land-use types in six typical suburban counties (samples) by geographic information system (GIS). Obvious displacements of corresponding centroids of agricultural land-use types in the samples demonstrates that configurations of agricultural land use have been destroyed in different parts of suburban Beijing. Furthermore, some typical patterns are explored according to the direction of displacement, which is driven mainly by urbanisation, topography, economic development and land-use policies. Land-use policies are shown to play more direct roles in spatial configuration changes of agricultural land use than other factors. It can be concluded that agricultural land-use configuration in suburban Beijing is affected by land resource balance among economic development, grain production and ecological protection. [ABSTRACT FROM AUTHOR]

The definition of "Digital Water Conservancy" is proposed on the basis of "Digital Earth" in this paper. The necessity, feasibility, construction principles of "Digital Water Conservancy" are analysed, and the framework of it is proposed, that is: key technology, basic infrastructure, and comprehensive applications. The key technology is composed of spatial information technology, management information technology, and comprehensive information technology; the basic infrastructure consists of National Information Infrastructure (Nil), National Spatial Data Infrastructure (NSDI), special data of water conservancy and security measures; the comprehensive applications are made up of the management system, decision-making models, and application systems. The above three levels supply hardware and solftware to water conservancy around data acquisition and updating, processing and accessing, information extraction and analysis, propagation of information, building and updating of databases, web and transmission, and decision-making support. A spatial information infrastructure, special data of water conservancy, and decision-making models are the core and are discussed in detail. Digital Water Conservancy is a large and complex systematic engineering, but it can be regarded as being composed of points (reservoirs and lakes), lines (rivers and their watersheds), and regions (oceans). A digital reservoir analysis is carried out in Xue Ye Reservoir, Shandong Province to provide experience for informatisation of water conservancy in China. [ABSTRACT FROM AUTHOR]

The ecological environment in the Tarim River Basin is extremely fragile. The ecological problems resulting from local economic development in this region have been a hot topic for the ecological scientists. There is a new trend to use information technologies to monitor the ecological environment dynamically by means of the modem information technologies. To meet the constant requirements of long-term monitoring of a region ecological environment, this paper focuses on the vegetation coverage and land desertification on the basis of the information technologies of remote sensing (RS), geographic positioning systems (GPS), geographic information systems (GIS), and data warehouse, applying the theory of the integrative spatial and attribute data, seamless integration of multi-source data. The ecological environment for the lower reaches of the Tarim River is analysed qualitatively and quantitatively. The investigated database is established and managed through multisource and multi-type massive data, which are collected from three periods of the remote sensing images and background data in 1999, 2002 and 2004, respectively. The methods of system classification, remote sensing interpretation, vegetation coverage, conversion models construction, and massive data built database are applied to analyse the data concerned during the dynamically monitoring the ecological environment in the Tarim River Basin. The results show that the vegetation coverage has increased gradually each year after the emergent water transportation project was started, whereas the desertification area has decreased, some sand areas have obviously retreated. The speed of improvement in the east part of the river has been higher than in the west. The ecological environment in the lower reaches of the Tarim River has tended to improve after the emergent water transportation project in the lower reaches of the Tarim River Basin. In conclusion, the emergent water delivery plays a decisive and significant role in promoting the ecological environment in this region. [ABSTRACT FROM AUTHOR]

A decision support tool which integrated a geographic information system (GIS) with decision tree models to predict pasture production and pasture responses to phosphate (P) and nitrogen (N) fertiliser was assessed on two farms with contrasting climate in New Zealand. Scenarios of rainfall variability and different fertiliser application strategies were also analysed in this assessment. The results indicated that the models performed well in generating reliable predictions of pasture production and fertiliser responses. The integration of the decision tree models with the GIS provides an efficient tool to assess feed availability and to optimise fertiliser application strategies over landscapes at fine (paddock) scale with considerations of climate variability and environmental impact. The limitations of this decision support tool and possible improvements are also discussed. [ABSTRACT FROM AUTHOR]

In this study, a web-GIS based support system for rural residential land consolidation in China was designed to evaluate the potential and objectives for rural land consolidation. It was developed using ASP.NET. ArclMS, ArcSDE and SQL Server technologies. The results show: (I) that according to the potential evaluation, the major rural consolidation areas are concentrated in the north-east of China, east China, north China and Inner Mongolia. These account for 65% of the total potential area in 2010; (2) that based on the rural consolidation objectives analysis, the major rural consolidation areas are concentrated in north-east China, east China, north China, Inner Mongolia and Xinjiang province. These account for 75% of the total consolidation objective area in 2020; (3) that the data can be shared and transported by the system on the internet. [ABSTRACT FROM AUTHOR]

Soil-salinisation has become an increasingly severe form of soil degradation due to climate variability and human disturbance in arid and semiarid areas. A cellular automata (CA) model was used by integrating a geographic information system (GIS) and remote sensing. Spatial and attribute data from Changling County were analysed to form a database in the GIS. Factors for soil-salinisation were confirmed. A soil salinity forecast formula was obtained by analysing the soil-salinisation system in Changling County. The CA model and database were integrated to simulate and forecast the soilsalinisation spatial-temporal distribution and its evolution. The results indicate the CA model is an effective decision-making support system for the prevention and control of soil-salinisation. [ABSTRACT FROM AUTHOR]

Path planning is a key technique to realise autonomous navigation of farm machines. Based on MapObjects, a Geographic Information System (GIS) for autonomous navigation was developed with Visual C++. A path search algorithm used to guide machines to track the desired path was designed. A Global Positioning System (GPS) was adopted in this algorithm to determine the current position of the machine. A path preview algorithm was designed to estimate the future position for the machine. On the basis of this system, dynamic tracking and display of the position was realised and the optimal path was provided through path planning. [ABSTRACT FROM AUTHOR]

To make a dynamic analysis of ecological capacity and a quantitative analysis of ecological compensation, to promote the sustainable development in a nature reserve, and to make Po-yang Lake Nature Reserve as an example, the authors obtained information on land-use change in the years 1985, 1995, 2005 in Po-yang Lake Nature Reserve based on RS and GIS. Ecological capacity was quantified and its development change, spatial characteristics, and the sustainable development status of the nature reserve with ecological deficits and surpluses were analysed. Results show that land use had been stable since the Po-yang Lake Nature Reserve came into existence. The change compared grassland (increased 15.22%), water body (increased 7.05%) and unused land (decreased 18.19%). The ecological capacity improved from 1985 to 2005 (the per capita ecological capacity from 0.8284 ha to 1.0534 ha). Among nine villages and towns in the reserve, the ecological surplus villages and towns were Wucheng, Tiehe and Changyi, the ecological balance villages and towns deficit were Sanjiao and Shahu. The remainder were in ecological deficit. In all of the nature reserve, the ecological capacity in the southeastern area was in surplus but that in the north-west was in deficit. The degree of ecological harmony was 1.414, which proves that the sustainable development state in Po-yang Lake Nature Reserve was under sustainable status. In 2005, the ecological footprint efficiency was 8382 yuan/ha, and the agricultural ecological footprint efficiency was 3204 yuan/ha. The lowest ecological compensation was 1725 yuan per family or 403 yuan per person, and the equal ecological compensation was 3798 yuan per family or 888 yuan per person. [ABSTRACT FROM AUTHOR]