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Abstract: Land suitability evaluation can assist in the efficient use of land resources at a regional level. This is an important issue because of the pressures that an increasing population and economic growth have put on limited land resources. Matter-element theory, which was first put forward by the Chinese mathematician Cai Wen, has shown potential for solving incompatibility problems. Based on the matter-element model, this paper uses land use, roads, water bodies, population density, distance from center of the city, geodetic height, and slope as factors in modeling land suitability for development. Zengcheng, an urban–rural administration was used as a case study for applying the matter-element model to assessing the suitability of land for development. The model was cross referenced with local urban plans for verification and the results of this study show that the model constructed was effective at assessing the suitability of land for development. According to both the classification map created using the matter-element model and the statistics on the of land suitability classes, the study area was found to have a considerable amount of land which is highly suitable for development. After the category ‘highly suitable’, the next largest total land area was in the category of ‘not suitable’ for development, while there was relatively little land classified as moderately and marginally suitable. The percentage of the total land area of each class of suitability was 41.80%, 34.22%, 16.35% and 7.64%, respectively. Apart from this, the study also demonstrated the advantage of matter-element models over fuzzy theory, as they provide much more information. For example, all integrated degree of all classes in the paper had ranges from −1 to 1, but differed from each other by percentage. In the category of ‘highly suitable’ only 45.51% of matter-elements fully conformed to the criteria (those within a range of 0–0.5925), while the remainder (54.49%) did not corresponded to the requirements of the category, but did have the potential to do so with relatively few changes (those within a range of −0.3923–0 degrees). This data provides us with an understanding of the potential and limitation to development of the land in the region. [Copyright &y& Elsevier]

Abstract: Land use change has significant impacts on hydrologic processes at the watershed level. This paper combines an empirical land use change model and an event-scale, rainfall-runoff model to quantify the impacts of potential land use change on the storm-runoff generation in the Xitiaoxi basin upstream of Taihu Lake watershed. The HEC–HMS rainfall-runoff model is calibrated and validated for 7 storm events in the study area, and the results show good consistency between the simulated and measured hydrographs at the outlet of the basin with Nash–Sutcliff efficiency ranging from 75% to 95%. Then two future land use scenarios for the year 2050 are forecasted using the CLUE-s model based on the land use of 2002: (1) scenario A with an increase in urban area from 9.2% to 17% of the entire watershed and (2) scenario B with an increase from 9.2% to 14%. Finally, the calibrated HEC–HMS model is applied for these future land use scenarios under designed storms with different recurrence intervals to assess the potential land use impacts on the storm-runoff generation. The results indicate that the future land use scenarios are projected to increase the total runoff as well as the peak discharge, and that the magnitude of increment relates to the expansion rate of built-up area. In the case of rainstorms with recurrence intervals of 10, 50 and 100 years, the simulated peak discharges increase by 3.8%, 2.6% and 2.3% under scenario A, and by 2.8%, 1.9% and 1.7% under scenario B, respectively; while the total runoff is projected to increase by 4.7%, 3.4% and 3.0% under scenario A, and by 3.3%, 2.5% and 2.1% under scenario B. It can be concluded that the sensitivity of hydrologic response to land use change tends to increase as the recurrence interval of rainfall events decreases. Additionally, remarkable spatial variations of the land use changes and its impacts can be observed at the subbasin level, and the most sensitive subbasin is closeby the city. The results of this paper can provide useful support for land use planning and management, and the methods applied here have proved a useful tool for land use impact studies. [Copyright &y& Elsevier]

Understanding spatiotemporal urbanization is one of the key questions related to sustainable urbanization in the drylands of northern China (DNC). However, urban expansion in the DNC has not been quantified and assessed effectively due to a lack of reliable data and methods. In this paper, we investigate urban expansion in the DNC at multiple scales, ranging from the whole region to four dryland subtypes, and six urban agglomerations in the DNC from 1992 to 2015. We also simulate urban expansion in the DNC from 2015 to 2050 by coupling the scenario framework of the Shared Socioeconomic Pathways (SSPs) with the Land Use Scenario Dynamics-urban (LUSD-urban) model. Despite of the uncertainty in the research, our findings provide useful insight into the past and the future urban expansion in the DNC. The results indicate that the urban land in the DNC expanded rapidly from 4110 km 2 in 1992 to 20,969 km 2 in 2015. Furthermore, the urban land in the DNC will continue to expand from 20,969 km 2 to 22,987–36,622 km 2 by 2040, with an annual growth of 80.72–403.48 km 2 under all SSPs. Thus, it is suggested that effective measures are urgently needed to facilitate sustainable urban development in the DNC. [ABSTRACT FROM AUTHOR]

Abstract: Based on gray error GM (1,1) model, the paper proposed an improved error GM (1,1) model, and used this model to predict cultivated land in Yiyang. The results show that the improved error GM (1,1) model has high prediction accuracy, and better simulation results. And the results conform to the cultivated quantity change rule of Yiyang City, that is, the land area of Yiyang City, will appear in the next few years, modest growth trend, but the per capita arable land is still in the alert level of the United Nations. Therefore, protection of cultivated resources, rational utilization and protection of arable land are urgent tasks. [Copyright &y& Elsevier]

Abstract: Previous studies have revealed that statistical methods can be used to analyze land-leasing parcel data. However, the conventional statistical methods used in land analysis have some limitations, especially in cases of limited observational data. In this paper, with the help of geographic information system (GIS) techniques, a partial least squares (PLS) path model is applied to study the relationship between residential land prices and various determinants through a case study of Beijing in China. From a preliminary analysis, four latent variables are selected: accessibility of the workplace center, livability, traffic, and environment facilities. The results show that the observation variables have a strong explanatory power for their corresponding latent variables, and the four latent variables have varying impacts on residential land prices. Of the latent variables, accessibility to the workplace center has the strongest impact on the residential land price. [Copyright &y& Elsevier]

This paper describes the development of a land use model coupling ecosystem processes. For a given land use pattern in a region, a built-in regional ecosystem model (TESim) simulates leaf physiology of plants, carbon and nitrogen dynamics, and hydrological processes including runoff generation and run-on re-absorption, as well as runoff-induced soil erosion and carbon and nitrogen loss from ecosystems. The simulation results for a certain period from 1976 to 1999 were then used to support land use decisions and to assess the impacts of land use changes on environment. In the coupling model, the land use type for a land unit was determined by optimization of a weighted suitability derived from expert knowledge about the ecosystem state and site conditions. The model was applied to the temperate crop-pasture band in northern China (CCPB) to analyze the interactions between land use and major ecosystem processes and functions and to indicate the added value of the feedbacks by comparing simulations with and without the coupling and feedbacks between land use module and ecosystem processes. The results indicated that the current land use in CCPB is neither economical nor ecologically judicious. The scenario with feedbacks increased NPP by 46.78gCm−2 a−1, or 32.23% of the scenario without feedbacks, also decreased soil erosion by 0.65kgm−2 a−1, or 23.13%. Without altering the regional land use structure (proportions of each land use type). The system developed in this study potentially benefits both land managers and researchers. [Copyright &y& Elsevier]