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Zheng X.,Zhejiang University | Yu Z.,Zhejiang University | Ao W.,Zhejiang Land Surveying and Planning Institute | Wang Y.,Zhejiang Land Surveying and Planning Institute | And 5 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

There is an increasing need to understand pattern and growth of impervious surfaces in rural regions. However, studies using remote sensing of impervious surfaces have often focused on mapping impervious surfaces in urban regions with less emphasis placed on the rural impervious surfaces. In this paper, we proposed a new index, Rural Impervious Surface Index (RISI) by taking advantage of narrow spectral bands of Landsat 8 OLI for estimating impervious surfaces within rural land covers. This index is based on the combination of Normalized Difference Built-up Index (NDBI), Soil Adjusted Vegetation Index (SAVI) and Soil Index (SI). Respectively, these represent the three major rural land covers components: impervious surfaces, vegetation, and soil. The index was further used for estimating fraction of impervious surfaces using fuzzy KNN classifier. The performance of this technique was also compared with Linear Spectral Mixture Analysis (LSMA). Our results showed that RISI could accurately detect spatial pattern of rural impervious surfaces due to the suppressing background noise and minimizing spectral confusion. Accuracy assessment revealed that incorporation of RISI with fuzzy KNN classification generates higher correlation coefficient, lower root mean square and systematic error compared to the LSMA technique. © 2014 SPIE. Source


Wu H.-X.,College of Public Administration | Jiang Y.-G.,Fuyang Agriculture Bureau | Chen J.-M.,Zhejiang Land Surveying and Planning Institute | Dai Y.-Y.,Zhejiang Land Surveying and Planning Institute | And 2 more authors.
Chinese Journal of Applied Ecology | Year: 2011

Rice productivity is the key factor affecting rice production and its sustainable development. Based on the gradation of cultivated land quality at county-level, this paper evaluated the rice productivity in Fuyang County of Zhejiang Province, and, through selected sampling field investigation and according to the land productivity index of paddy field quality, a model for assessing rice achievable productivity was established, aimed to analyze the regional rice productivity and its achievable productivity. In the study area, there was a positive correlation between the land productivity index and rice yield. For single cropping rice, its achievable productivity was 1.70×105t, being 1.6 times of its realistic productivity (1.04×105t). In 2009, the realistic rice productivity per unit area was 7676 kg·hm-2, and the achievable productivity was 8831 kg·hm-2, with a production potentiality of +15%, a big potential of rice production capacity in the county. Through the analyses of rice productivity, relative superiority of rice production scale, and its growth potential index in the villages and towns, the rice production of Fuyang County was divided into three regions, i.e., key enhancement region, optimization construction region, and development protection region. Source


Tan Y.,Zhejiang University | Han C.,Zhejiang University | Wu C.,Zhejiang University | Zhao Z.,Zhejiang Land Surveying and Planning Institute | Wang Q.,China Land Surveying and Planning Institute
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2013

Topsoil stripping is helpful to improve land productivity, protect high-quality land resources, and most importantly, preserve the environment and ecosystem from destruction. In the U.S.A., Canada, Japan, and Australia, topsoil stripping is typically effective and efficient, based on the law, policy, technical standards, and availability of sufficient funds. The purpose of this paper is to analyze the circumstances, organizational patterns and applied patterns, and characteristics of topsoil stripping in these representative countries by using the methods of literature consultation and comparative analysis. Moreover, the circumstances, patterns, and dilemma of topsoil stripping in China are also studied. Based on that, our final purpose is to give some recommendations to make topsoil stripping more reasonable and scientific in China. It is concluded that there exists three main patterns of organization and administration, to be specific, government-centered patterns, joint-management patterns, and planning-centered patterns. They are all useful to ensure that the topsoil stripping could be carried out smoothly in spite of their different operating processes and other details. In terms of the appliance of topsoil: one is bringing topsoil back to the original land, the most important procedure here is topsoil storage; another is bringing topsoil to new land, besides topsoil storage, another key procedure here is topsoil transportation. Moreover, in these countries, it is shown that topsoil stripping has six main characteristics: one is comprehensive goals, i.e. improving land productivity, protecting land resources and environment, preserving the culture and so on; the second is multiple subjects, government, the third is that sector, enterprises and individuals actively participate in stripping topsoil; the third is sufficient funds, and they come from an Insurance Fund, Land Rehabilitation Fund, government allocated funds and charitable contribution; the fourth is formal technology, as these countries establish specific programs, technology and acceptance standards for topsoil stripping to give guidance on various projects, soil types, and each process of topsoil stripping; the fifth is legislative appliance, that is, topsoil stripping is legislatively based on laws, acts, regulations, and relative standards; the sixth is spatial variance, i.e., spatial distinctions and relations which stem from the spatial characteristics of land. Correspondingly, in China, there have been three patterns of topsoil stripping: administration-centered patterns, market-oriented patterns, and administration-market patterns. However, it is still unclear that which pattern is the most reasonable one, because they were successfully used in various programs of different regions in China. According to the current practice of topsoil stripping, there are a variety of factors which limit the development of topsoil stripping but lack of effective basic laws, a powerful system guarantee, an appropriate technical standard, and the active participation of subjects are the major obstacles to stripping and applying topsoil. To make one final point, learning from the successful experience of topsoil stripping in these countries, legislating laws and regulations, using various administrative methods, making refined technical standards, and defining a functional division of relative sectors are the strategies which can be used to improve topsoil stripping in China. Source


Ma L.,Zhejiang University | Wu D.,The 2nd Surveying and Mapping Institute of Zhejiang | Deng J.,Zhejiang University | Deng J.,University of Oklahoma | And 5 more authors.
European Journal of Remote Sensing | Year: 2015

The Economic and Technological Development Zone (ETDZ) is a critical urban economic and functional area. Inefficient land exploitation and insufficient supervision have led to a great waste of land resources. The timely and precise extraction of residential and industrial building type, area and density information is urgently needed and essential for sustainable land use development. This study attempted to discriminate residential and industrial buildings by integrating LiDAR data, a lacunarity algorithm, object-based segmentation and a decision tree classifier. All buildings were identified using a normalized digital surface model (nDSM) and object-based segmentation. Lacunarity features and a decision tree classifier were then adopted to discriminate building types. An accuracy assessment indicated that the proposed method can effectively identify residential and industrial buildings. The overall classification accuracy was greater than 85.67% for both of the two test blocks. A comparison with results derived from the nDSM alone showed a significantly improved classification accuracy using the KHAT statistics from a Kappa analysis. The results not only confirmed the applicability and effectiveness of the combined method but also provided fundamental information for evaluating land use in the ETDZ. © 2015, Associazione Italiana di Telerilevamento. All rights reserved. Source

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