.
9.Evaluating the effectiveness of landscape metrics in quantifying spatial patterns
Ecological Indicators, 2010, 10(2): 217-223
Jian Peng, Yanglin Wang*, Yuan Zhang, Jiansheng Wu, Weifeng Li, You Li
Abstract: The effectiveness of landscape metrics in quantifying spatial patterns is fundamental to metrics assessment. Setting 36 simulated landscapes as sample space and focusing on 23 widely used landscape metrics, their effectiveness in quantifying the complexity of such spatial pattern components as number of patch types, area ratio of patch types and patch aggregation level, were analyzed with the application of the multivariate linear regression analysis method. The results showed that all the metrics were effective in quantifying a certain component of spatial patterns, and proved that what the metrics quantified were not a single component but the complexity of several components of spatial patterns. The study also showed a distinct inconsistency between the performances of landscape metrics in simulated landscapes and the real urban landscape of Shenzhen, China. It was suggested that the inconsistency resulted from the difference of the correlation among spatial pattern components between simulated and real landscapes. After considering the very difference, the changes of all 23 landscape metrics against changing of number of patch types in simulated landscapes were consistent with those in the real landscape. The phenomenon was deduced as the sign effect of spatial pattern components on landscape metrics, which was of great significance to the proper use of landscape metrics.
8.Urbanization and Informal Development in China Urban Villages in Shenzhen
International Journal of Urban and Regional Research, 2009, 33(4): 957-973
Ya Ping Wang, Yanglin Wang, Jiansheng Wu
Abstract: Informal housing and industrial developments in the so-called urban villages have been key features of the recent Chinese urbanization. In this article we will examine the development of urban villages in one of the most dynamic Chinese cities - Shenzhen. The article first reviews the urbanization and migration process in the region and the emergence of urban villages. It then examines informal housing, commercial and industrial developments in these villages. We analyse the politics of village urbanization and highlight the important relationship between migration and informal village development. We emphasize the contribution made by urban villages in providing affordable housing and jobs for the low-income population during the rapid urbanization and urge cautious consideration with regard to hasty and large-scale redevelopment of these villages. We conclude that the development of urban villages is a very important part of the urbanization process.
7.Rural Land Use Change during 1986–2002 in Lijiang, China, Based on Remote Sensing and GIS Data
Sensors, 2008, 8(12): 8201-8223
Jian Peng, Jiansheng Wu*, He Yin, Zhengguo Li, Qing Chang, Tianlong Mu
Abstract: As a local environmental issue with global importance, land use/land cover change (LUCC) has always been one of the key issues in geography and environmental studies with the expansion of regional case studies. While most of LUCC studies in China have focused on urban land use change, meanwhile, compared with the rapid change of urban land use in the coastal areas of eastern China, slow but distinct rural land use changes have also occurred in the mountainous areas of western China since the late 1980s. In this case through a study in Lijiang County of Yunnan Province, with the application of remote sensing data and geographic information system techniques, the process of rural land use change in mountain areas of western China was monitored through extensive statistical analysis of detailed regional data. The results showed significant increases in construction land, paddy field and dry land, and a decrease in dense forest land and waste grassland between 1986 and 2002. The conversions between dense forest land and sparse forest land, grassland, waste grassland and dry land were the primary processes of rural land use change. Sparse forest land had the highest rate of land use change, with glacier or snow-capped land the lowest; while human settlement and rural economic development were found to be the main driving forces of regional difference in the integrated land use change rate among the 24 towns of Lijiang County. Quantified through landscape metrics, spatial patterns of rural land use change were represented as an increase in landscape diversity and landscape fragmentation, and the regularization of patch shapes, suggesting the intensification of human disturbances and degradation of ecological quality in the rural landscape.
Journal of Arid Environments, 2008, 72(6): 974-985
Zhengguo Li, Yanglin Wang*, Qingbo Zhou, Jiansheng Wu, Jian Peng, Hsiaofei Chang
Abstract: Vegetation coverage and surface temperature are important parameters in describing the characteristics of land cover, which in combination can provide information on vegetation and soil moisture conditions at the surface. This paper aims to estimate spatial and temporal patterns of soil moisture in the Loess Plateau, China. Using Terra/MODIS images for each 10-day period in 2004 covering the semi-arid North Shaanxi Loess Plateau, a simplified land surface dryness index (Temperature–Vegetation Dryness Index, TVDI) developed by Sandholt [Sandholt, I., Rasmussena, K, Andersenb, J., 2002. A simple interpretation of the surface temperature/vegetation index space for assessment of surface moisture status. Remote Sensing of Environment 79, 213–224.] was used to determine the relationship between surface temperature and vegetation index. From the analysis, it can be inferred that the trend in seasonal change of TVDI is high values in the dry season (spring or summer) and low values in the rainy season (autumn or winter). Moreover, the land surface moisture of each watershed had its seasonal characteristics. The relationship between TVDI and land cover types indicated that water-retention in forest and shrub areas was better than cropland and rangeland in relatively wet conditions, and rangeland was better than forest and shrub areas in dry conditions.
5.Environmental Impact Assessment of Industrial Structure Change in a Rural Region of China
Environmental Monitoring and Assessment, 2007, 132(1-3): 419-428
Jian Peng, Yanglin Wang, Minting Ye, Jiansheng Wu, Yuan Zhang
Abstract: As the embodiment of human activities, the change of regional industrial structure is an essential driving factor of global environmental change. Consequently, the research on the change of regional industrial structure and associated effects on the environment is one of the key issues of researches on sustainable development, human鈥揺nvironment relationship, and regional response to global environment change. However, compared to the flourish of researches on environmental impact assessment of industrial departments, few studies have been conducted to assess the environmental impact of regional industrial structure. In this study, based on a synthetic analysis of environmental disturbances of different industrial departments, the environmental impact coefficient of industrial department associated with the index of environmental impact of industrial structure was constructed, so as to make a quantitative assessment of environmental impact of the change of regional industrial structure. And the results of the case study in Lijiang City, a rural region of China, have showed that there are two obvious changes of industrial structure in the study area from 1992 to 2003, associated with a continuous decreasing of the index of environmental impact of industrial structure, which indicated a positive environmental effects of the change of regional industrial structure.
4.Evaluation for sustainable land use in mountain areas of Northwestern Yunnan Province, China
Environmental Monitoring and Assessment, 2007, 133(1-3): 407-415
Jian Peng, Yanglin Wang, Jiansheng Wu, Qing Chang, Yuan Zhang
Abstract: As an important component of sustainable development in mountain areas, evaluation for sustainable land use is always one of the hotpots of researches on sustainable development. Traditional evaluation for sustainable land use mainly focuses on the sustainability of land use model and biological production on temporal scale, and overlooks the effects of land use patterns on the sustainability, while landscape ecology can be a good help to realize the spatial analysis of sustainable land use. In this study, a synthetic evaluation indexes system for sustainable land use was constructed through the application of landscape metrics. Taking Yongsheng County of Yunnan Province, China as a case study, a series of quantitative evaluation were conducted in 1996, 1999 and 2001, to monitor the temporal dynamics of regional land use sustainability. Two indicators, contributing amount of indexes, and obstacle amount of indexes, were also set up to ascertain the significance of all the evaluation indexes to the evaluation results. The results showed that, in the study phases, the land use sustainability of the whole county had been low with a stable but great spatial difference, and great changes took place in regional land use system in 1999 with the deviation from the aim of sustainable land use. It also showed that, the most important indexes contributing for the land use sustainability in the study period, were the indexes of population density and land use degree, followed by the index of landscape diversity and cropping index. And the most important indexes counteracting the land use sustainability were the indexes of per unit area total production value of industry and agriculture, per unit area yield of cereal crops, landscape fragmentation, followed by the indexes of per unit area yield of economic crops and fertilizer consume per unit area.
3.Rural industrial structure and landscape diversity Correlation research
International Journal of Sustainable Development and World Ecology, 2007, 14(3): 268-277
Jian Peng, Yanglin Wang, Juan Jing, Qing Chang, Jiansheng Wu
Abstract: Landscape diversity reflects the integrated natural characteristics of rural areas, to some extent, while industrial structure shows the regional social economic characteristics. Therefore, correlation research on rural industrial structure and landscape diversity may couple the natural environment and social economy, which is of great importance to rural sustainable development. In this paper, we carried through this research from two aspects. First, we made a qualitative analysis of the hierarchical correlation beween rural industrial structure and landscape diversity, and the correlation during different historical periods was also summarized. Second, taking Yongsheng County, Yunnan Province, China as a case study, we applied the method of hierarchical clustering to make a quantitative analysis of the clustering correlation between rural industrial structure and landscape diversity. The results show that there are correlations between rural industrial structure and landscape diversity. That is, different industrial structures may result in similar landscape diversity in developed rural areas; while in developing rural areas industrial structure cannot exclusively determine landscape diversity, which is also influenced by natural factors, such as landform, physiognomy and climate.
2.Ecological effects associated with land use change in China s southwest agricultural landscape
International Journal of Sustainable Development and World Ecology, 2006, 13(4): 315-325
Jian Peng, Yanglin Wang, Jiansheng Wu, Jun Yue, Yuan Zhang, Weifeng Li
Abstract: Research on land-use and land-cover change, with associated effects on the ecoenvironment, is a key to understanding global change. The concept of 'ecosystem services' is also a hot issue in ecology and ecological economics. In this study, ecosystem service values are used to assess the ecological values of corresponding land-use types, so as to evaluate the ecological effects of regional land-use change. China's southwest agricultural landscape has unique ecological functions; but it also belongs to an ecologically fragile zone. Consequently, land-use change and associated ecological effects must be monitored to assure sustainable development of this area. Based on TM images in 1988, 1994 and 1999, the landscape classification maps of Yongsheng County were assessed using supervised classification and interactive modification methods. The transition matrix of land-use types and three indices of spatial patterns, patch-level, class-level and landscape-level indices, were calculated using models and GIS to examine the spatial patterns and dynamics of land use in the study area. The results show the influences of human activities and natural environmental elements, and that unused land has decreased rapidly, together with a continuous increase in forest during the past 11 years. There are also frequent intermediate transitions between farmland and unused land. An index for landscape diversity shows a tendency to increase, indicating that the proportions of each landscape element tended to average. Also, the decrease in the fractal dimension of unused land reveals that the effects of human activity are increasing. Ecological value calculations show that land-use change in Yongsheng County from 1988鈥1999 has resulted in positive ecological effects, with distinct spatial differences.
1.Evaluation for sustainable land use in coastal areas A landscape ecological prospect
International Journal of Sustainable Development and World Ecology, 2006, 13(1): 25-36
Jian Peng, Yanglin Wang, Weifeng Li, Jun Yue, Jiansheng Wu, Yuan Zhang
Abstract: Evaluation of sustainability is the core of research on sustainable land use. To a certain extent, traditional social, economic and ecological evaluation for sustainable land use can be regarded as an appraisal on the temporal scale without evaluation of spatial patterns. Landscape ecology can help to realize spatial evaluation for sustainable land use. In this paper, we construct landscape ecological indicators for evaluating sustainable coastal land use from the aspects of landscape productivity, threats and stability, to realize a synthetic temporal-spatial evaluation. These cover the five pillars of sustainable land use, i.e. productivity, security, protection, viability and acceptability. The results of applying landscape ecological evaluation to a case study in Wudi County in China show that land use sustainability is somewhat low and there are great regional differences between its 11 villages. We classified the 11 villages into 5 grades: strong sustainable land use, sustainable land use, weak sustainable land use, weak unsustainable land use, and strong unsustainable land use. Each grade has different land use characteristics and differs in the counter-measures required. But the core countermeasures in all the grades are to improve landscape productivity, to reduce human threats and to optimize landscape patterns.
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