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Detection of short-term urban land use changes by combining SAR time series images and spectral angle mapping

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Frontiers of Earth Science 2019年第3期13卷 495-509页

作者： Zhuokun PAN Yueming HU Guangxing WANG College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642China key laboratory of Construction land Transformation Ministry of Land and ResourcesGuangzhou 510642China guangdong provincial key laboratory of land use and consolidation Guangzhou 510642China guangdong provincial land Information Engineering Research Center Guangzhou 510642China College of Agriculture and Animal Husbandry Qinghai UniversityXining 810016China Department of Geography Southern Illinois University at CarbondaleIL 62901USA

Rapid urban sprawl and re-construction of old towns have been leading to great changes of land use in cities of China. To witness short-term urban land use changes, rapid or real time remote sensing images and effective detection methods are required. With the availability of short repeat cycle, relatively high spatial resolution, and weather-independent Synthetic Aperture Radar (SAR) remotely sensed data, detection of short-term urban land use changes becomes possible. This paper adopts newly released Sentinel-1 SAR data for urban change detection in Tianhe District of Guangzhou City in Southern China, where dramatic urban redevelopment practices have been taking place in past years. An integrative method that combines the SAR time series data and a spectral angle mapping (SAM) was developed and applied to detect the short-term land use changes. Linear trend transformations of the SAR time series data were first conducted to reveal patterns of substantial changes. Spectral mixture analysis was then conducted to extract temporal endmembers to reflect the land development patterns based on the SAR backscattering intensities over time. Moreover, SAM was applied to extract the information of significant increase and decrease patterns. The results of validation and method comparison showed a significant capability of both the proposed method and the SAR time series images for detecting the short-term urban land use changes. The method received an overall accuracy of 78%, being more accurate than that using a bi-temporal image change detection method. The results revealed land use conversions due to the removal of old buildings and their replacement by new construction. This implies that SAR time series data reflects the spatiotemporal evolution of urban constructed areas within a short time period and this study provided the potential for detecting changes that requires continuously short-term capability, and could be potential in other landscapes.

关键词： Sentinel-1 SAR time series images urban land use change detection temporal endmember spectral angle mapping

Influence of phosphate on deposition and detachment of TiO2 nanoparticles in soil

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Frontiers of Environmental Science & Engineering 2019年第5期13卷 163-173页

作者： Zhan Wang Chongyang Shen Yichun Du Yulong Zhang Baoguo Li Department of Soil and Water Sciences China Agricultural UniversityBeijing 100193China College of land and Environment Shenyang Agricultural UniversityShenyang 110866China key laboratory of Degraded and Unused land consolidation Engineering Ministry of Land and ResourcesShaanxi Provincial Land Engineering Construction Group Co.Ltd.Xi’an 710075China

The widespread use of TiO2 nanoparticles (NPs) makes inevitable their release into the soil. Phosphate is also widespread within soil, and is likely copresent with TiO2 NPs. However, the influence of phosphate on deposition/release— and thereby on transport— of TiO2 NPs in soil is yet to be elucidated. In this study we conducted saturated column experiments to systematically examine the transport of TiO2 NPs in soil amended with phosphate at different ionic strengths (ISs) (1, 10, 100 mmol/L NaCl) and pHs (4 and 9). Results show that the deposition of TiO2 NPs decreased with decreasing IS, increasing pH, and when soil absorbed phosphate. These observations are qualitatively in agreement with Derjaguin-landau-Verwey-Overbeek (DLVO) interaction energy calculations, because the repulsive energy barrier is larger and secondary minimum depth is smaller at a lower IS, higher pH, and in the presence of phosphate. Accordingly, both primary- and secondary-minimum deposition were inhibited. Interestingly, although the deposition was less at higher pH and in the presence of phosphate, the subsequent spontaneous detachment and detachment by reduction of solution IS in these cases were greater. In addition, the presence of phosphate in the solution can cause a small quantity of attached TiO2 NPs to detach, even without perturbations of physical and chemical conditions. Our study was the first to investigate the influence of phosphate on detachment of TiO2 NPs and the results have important implication for accurate prediction of fate and transport of TiO2 NPs in subsurface environments.

关键词： Phosphate TiO2 nanoparticles Transport Soil Deposition Detachment

Generating high spatiotemporal resolution LAI based on MODIS/GF-1 data and combined Kriging-Cressman interpolation

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International Journal of Agricultural and Biological Engineering 2016年第5期9卷 120-131页

作者： Liu Zhenhua Huang Rugen Hu Yueming Fan Shudi Feng Peihua College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642China guangdong provincial key laboratory of land use and consolidation Guangzhou 510642China guangdong Province Engineering Research Center for land Information Technology Guangzhou 510642China key laboratory of the Ministry of land and Resources for Construction land Transformation Guangzhou 510642China Guangzhou Surveying and Mapping Geographic Information Industry Engineering Technology Research Center Guangzhou 510642China Pearl River Comprehensive Technology Center(Information Center)of Pearl Water Resources Commission Guangzhou510611China

Generation of high spatial and temporal resolution LAI(leaf area index)products is challenging because higher spatial resolution remotely sensed data usually have coarse temporal resolutions and vice *** this study,a novel method that combining Kriging interpolation and Cressman interpolation was proposed to generate high spatial and temporal resolution LAI products by fusing Moderate Resolution Imaging SpectroRadiometer(MODIS)characterized by coarse spatial resolution and high temporal resolution and Gaofen-1(GF-1)with fine spatial resolution and coarse temporal *** method was applied to the Huangpu district of Guangzhou,guangdong,*** results showed that compared to field observation,the predicted values of LAI had an acceptable accuracy of 73.12%.Using Moran’s I index and Kolmogorov-Smirnov tests,it was found that the MODIS data were spatially auto-correlated and characterized by normal *** down the 1 km×1 km spatial resolution MODIS products to a spatial resolution of 30 m×30 m using point-Kriging resulted in a precision of 79.38%compared to the results at the same spatial resolution derived from an 8 m×8 m spatial resolution GF-1 image by scaling up using ***,the regression models that accounts for the relationship between NDVI(Normalized Difference Vegetation Index)and LAI based on MODIS data obtained the determination coefficients ranging from 0.833 to ***,the data fusion and interpolation of MODIS and GF-1 data using Cressman method generated high spatial and temporal resolution LAI maps,which showed reasonably spatial and temporal *** results imply that the proposed method is a powerful tool to create high spatial and temporal resolution LAI products.

关键词： data fusion MODIS GF-1 LAI spatiotemporal resolution spatial interpolation remote sensing

Monitoring behavior of poultry based on RFID radio frequency network

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International Journal of Agricultural and Biological Engineering 2016年第6期9卷 139-147页

作者： Zhang Feiyang Hu Yueming Chen Liancheng Guo Lihong Duan Wenjie Wang Lu College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642China guangdong Province Engineering Research Center for land Information Technology Guangzhou 510642China guangdong Province key laboratory for land use and consolidation Guangzhou 510642China guangdong Youyuan land Information Technology Co. LtdGuangzhou 510642China College of Mathematics and Informatics South China Agricultural UniversityGuangzhou 510642China

Poultry behavior monitoring is an important basis for the poultry disease *** monitoring is mostly used *** this work,the automatic monitoring system for assisting manual monitoring was *** data mining techniques were used to leverage the data collected by RFID ***,(1)weighing sensors and wireless networks of Multiple RFID-tag-collector groups were used to monitor the poultry behavior;(2)RFID tags were putted on individual poultry so that the moving time of the poultry between two RFID-tag-collectors could be ***,the characteristic functions of poultry behaviors such as speed,ability to snatch food and resting time could be extracted based on the distance between two RFID-tag-collectors and the relevant time parameters;(3)the sick,normal,active and other poultry groups were categorized by using the K-means method which utilizing the behavior characteristics and poultry weight data in data *** results demonstrated that accurate classifications could be obtained according to the poultry characteristics,and the clustering results matched with the results obtained by manual method to identify the poultry ***,the technique in this paper has great potential for large-scale poultry disease warning and poultry classification.

关键词： poultry behavior monitoring cloud computing internet of things(IoT) radio-frequency identification data mining

Optimized selection of suitable sites for farmland consolidation projects using multi-objective genetic algorithms

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International Journal of Agricultural and Biological Engineering 2014年第3期7卷 19-27页

作者： Wang Lu Huang Ningsheng Kuang Yaoqiu Zhou Jinhao Zhao Yuan Zhang Zhen Hu Yueming Guangzhou Institute of Geochemistry Chinese Academic of ScienceGuangzhou 510640Guangdong ProvinceChina University of Chinese Academic of Sciences Beijing 100039China College of Information South China Agricultural UniversityGuangzhou 510642Guangdong ProvinceChina guangdong Province land use and Remediation of the key laboratory Guangzhou 510642Guangdong ProvinceChina

In order to select suitable sites for farmland consolidation projects,correlation analysis and evolutionary algorithms were used to optimize the evaluation of ecological,social and economic factors,avoiding subjective selection and ignorance of spatial relationships among land ***-objective Genetic Algorithms(MOGA)were applied to select the best sites from the perspective of spatial relationship and land attribute *** carefully defined restrictions and variables,multi-objective optimization is able to select several suitable sites for farmland consolidation *** results from a case study in Yangshan,guangdong of China showed that the selected sites were on the central and southern Yangshan with expected flat terrain and abundant water *** empirical experiment also demonstrated that the proposed method is able to provide well selected sites for land consolidation projects.

关键词： farmland consolidation site selection evaluation index system multi-objective optimization genetic algorithm suitability

The Influence of Different land use Manners on Soil Aggregate Characteristics of consolidation and Returning to Field in Hollow Village of Hilly Area

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Asian Agricultural Research 2017年第10期9卷 26-32页

作者： Juan LI Shaanxi provincial land Engineering Construction Group key laboratory of Degraded and Unused land consolidation Engineering of Ministry of land and Resources

The research aimed to explore the influence of different land use manners on soil aggregate,and provide scientific basis for improving soil stability and production performance of consolidation and returning to field in hollow village of hilly area. After consolidation and returning to field in hollow village of hilly area of Chengcheng County,Shaanxi,5 kinds of land use manners were set for 1-year plantation test,and they were corn( C treatment),wheat( W treatment),vegetable( V treatment),medicinal material( M treatment) and control( no plantation: CK treatment). Soil aggregate distribution,mean mass diameter( WMD),geometric mean diameter( GMD),aggregate failure rate( PAD),unstable aggregate number( ELT) and fractal dimension( D) at 0-40 cm of soil layer were measured and analyzed by dry and wet sieving methods. The results showed that( i) soil aggregate number and size at 0-40 cm of soil layer by each treatment were all significantly better than CK treatment,and > 0. 25 mm of aggregate content by dry sieving method( DR0. 25) and >0. 25 mm of aggregate content by wet sieving method( WR0. 25) at 0-40 cm of soil layer in each treatment showed declining trend with soil layer depth increased;( ii) MWD and GMD sequences of each treatment at 0-40 cm of soil layer by dry and wet sieving methods were both W treatment > C treatment > M treatment > V treatment > CK treatment,and C treatment was conducive to increasing large aggregate content of surface soil,while W treatment was conducive to increasing large aggregate content of lower soil;( iii) the analysis by wet sieving method showed that PAD and ELT at 0-40 cm of soil layer in each treatment both showed similar " Z" shape trend,and each treatment was significantly lower than CK;( iv) D sequence at 0-40 cm of soil layer in each treatment was C treatment 0. 25 mm of aggregate content at 0-40 cm of soil layer by dry and wet si

关键词： Hollow village Soil aggregate Average mass diameter Geometric mean diameter Fractal dimension

Uphill or downhill?Cropland use change and its drivers from the perspective of slope spectrum

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Journal of Mountain Science 2024年第2期21卷 484-499页

作者： PAN Sipei LIANG Jiale CHEN Wanxu PENG Yelin College of land Management Nanjing Agricultural UniversityNanjing 210095China National&Local Joint Engineering Research Center for Rural land Resources use and consolidation Nanjing 210095China Jiangsu provincial key laboratory of Geographic Information Technology School of Geography and Ocean ScienceNanjing UniversityNanjing 210023China key laboratory of Natural Resources Monitoring and Supervision in Southern Hilly Region Ministry of Natural ResourcesChangsha 410118China Yunnan key laboratory of Plateau Geographic Processes and Environmental Changes Faculty of GeographyYunnan Normal UniversityKunming 650500China Hubei key laboratory of Regional Ecology and Environmental Change School of Geography and Information EngineeringChina University of GeosciencesWuhan 430074China

The continuous decrease of low-slope cropland resources caused by construction land crowding poses huge threat to regional sustainable development and food *** spectrum analysis of topographic and geomorphic features is considered as a digital terrain analysis method which reflects the macro-topographic features by using micro-topographic ***,pieces of studies have extended the concept of slope spectrum in the field of geoscience to construction land to explore its expansion law,while research on the slope trend of cropland from that perspective remains *** address the gap,in virtue of spatial analysis and geographically weighted regression(GWR)model,the cropland use change in the Yangtze River Basin(YRB)from 2000 to 2020 was analyzed and the driving factors were explored from the perspective of slope *** showed that the slope spectrum curves of cropland area-frequency in the YRB showed a first upward then a downward *** change curve of the slope spectrum of cropland in each province(municipality)exhibited various distribution *** analysis of morphological parameters of cropland slope spectrum revealed that the further down the YRB,the stronger the flattening characteristics,the more obvious the *** province experienced the greatest downhill cropland climbing(CLC)was Shannxi,while province experienced the highest uphill CLC was *** most common cropland use change type in the YRB was horizontal expansion *** factors affecting average cropland climbing index(ACCI)were quite stable in different periods,while population density(POP)changed from negative to positive during the study *** research is of practical significance for the rational utilization of cropland at the watershed scale.

关键词： Cropland climbing land use change Slope spectrum Driving factors Geographically weighted regression Yangtze River Basin

Quantifying foliar trait variation and covariation in sun and shade leaves using leaf spectroscopy in eastern North America

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Forest Ecosystems 2024年第5期11卷 728-742页

作者： Zhihui Wang Philip A.Townsend Eric L.Kruger Anna K.Schweiger guangdong provincial key laboratory of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and ApplicationGuangzhou Institute of GeographyGuangdong Academy of SciencesGuangzhou510070China Department of Forest and Wildlife Ecology University of Wisconsin-Madison1630 Linden DriveMadisonWI53706USA Department of land Resources and Environmental Sciences Montana State University334 Leon Johnson HallBozemanMT59717USA

Characterizing foliar trait variation in sun and shade leaves can provide insights into inter-and intra-species resource use strategies and plant response to environmental ***,datasets with records of multiple foliar traits from the same individual and including shade leaves are sparse,which limits our ability to investigate trait-trait,trait-environment relationships and trait coordination in both sun and shade *** presented a comprehensive dataset of 15 foliar traits from sun and shade leaves sampled with leaf spectroscopy,including 424 individuals of 110 plant species from 19 sites across eastern North *** investigated trait variation,covariation,scaling relationships with leaf mass,and the effects of environment,canopy position,and taxonomy on trait ***,sun leaves had higher leaf mass per area,nonstructural carbohydrates and total phenolics,lower mass-based chlorophyll a+b,carotenoids,phosphorus,and potassium,but exhibited species-specific *** between sun and shade leaf traits,and trait-environment relationships were overall consistent across *** main dimensions of foliar trait variation in seed plants were revealed including leaf economics traits,photosynthetic pigments,defense,and structural *** and canopy position collectively explained most of the foliar trait *** study highlights the importance of including intra-individual and intra-specific trait variation to improve our understanding of ecosystem *** findings have implications for efficient field sampling,and trait mapping with remote sensing.

关键词： Foliar traits Leaf trait variation Trait-environment covariation Shade leaves NEON Leaf spectroscopy

THE IMPACT OF DIFFERENT PHYSICAL PROCESSES AND THEIR PARAMETERIZATIONS ON FORECAST OF A HEAVY RAINFALL IN SOUTH CHINA IN ANNUALLY FIRST RAINING SEASON

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Journal of Tropical Meteorology 2015年第2期21卷 194-210页

作者：张旭斌万齐林薛纪善丁伟钰李昊睿 guangdong provincial key laboratory of Regional Numerical Weather Prediction CMA Institute of Tropical and Marine Meteorology CMA Chinese Academy of Meteorological Sciences

An ensemble prediction system based on the GRAPES model, using multi-physics, is used to discuss the influence of different physical processes in numerical models on forecast of heavy rainfall in South China in the annually first raining season(AFRS). Pattern, magnitude and area of precipitation, evolution of synoptic situation, as well as apparent heat source and apparent moisture sink between different ensemble members are comparatively analyzed. The choice of parameterization scheme for land-surface processes gives rise to the largest influence on the precipitation prediction. The influences of cumulus-convection and cloud-microphysics processes are mainly focused on heavy rainfall;the use of cumulus-convection parameterization tends to produce large-area and light rainfall. Change in parameterization schemes for land-surface and cumulus-convection processes both will cause prominent change in forecast of both dynamic and thermodynamic variables, while change in cloud-microphysics processes show primary impact on dynamic variables. Comparing simplified Arakawa-Schubert and Kain-Fritsch with Betts-Miller-Janjic schemes, SLAB with NOAH schemes, as well as both WRF single moment 6-class and NCEP 3-class with simplified explicit schemes of phase-mixed cloud and precipitation shows that the former predicts stronger low-level jets and high humidity concentration, more convective rainfall and local heavy rainfall, and have better performance in precipitation forecast. Appropriate parameterization schemes can reasonably describe the physical process related to heavy rainfall in South China in the AFRS, such as low-level convergence, latent heat release, vertical transport of heat and water vapor, thereby depicting the multi-scale interactions of low-level jet and meso-scale convective systems in heavy rainfall suitably, and improving the prediction of heavy rainfall in South China in the AFRS as a result.

关键词： numerical weather prediction heavy rainfall in South China in annually first raining season GRAPES model multi-physics parameterization ensemble prediction