Proceedings Volume 7491

PIAGENG 2009: Remote Sensing and Geoscience for Agricultural Engineering

Honghua Tan, Qi Luo
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Proceedings Volume 7491

PIAGENG 2009: Remote Sensing and Geoscience for Agricultural Engineering

Honghua Tan, Qi Luo
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Volume Details

Date Published: 10 July 2009
Contents: 2 Sessions, 41 Papers, 0 Presentations
Conference: International Conference on Photonics and Image in Agriculture Engineering (PIAGENG 2009) 2009
Volume Number: 7491

Table of Contents

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Table of Contents

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  • Front Matter: Volume 7491
  • PIAGENG 2009: Remote Sensing and Geoscience for Agricultural Engineering
Front Matter: Volume 7491
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Front Matter: Volume 7491
This PDF file contains the front matter associated with SPIE Proceedings Volume 7491, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and the Conference Committee listing.
PIAGENG 2009: Remote Sensing and Geoscience for Agricultural Engineering
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GIS-based fine spatial climate ecological regionalization of sweet orange in the Three Gorges reservoir area
Yanghua Gao, Zhijun Chen, Hui Ju, et al.
According to different ecological conditions of various of sweet orange and the different of consumption of fresh sweet orange and processing of sweet orange, the article determined the main index of climate and ecological factors, which impact the growth of citrus, based on the major climate resources and meteorological disasters which impact the growth of citrus in Three Gorges reservoir area. This article studied the spatial distribution of the average annual total solar radiation, the average annual temperature and the average annual relative humidity by methods of regression, simulation, interpolation with the help of ARCGIS and 1:250000 DEM (Districts and counties with 1:50000). In the above, the article made the fine spatial climate ecological division of sweet orange in Three Gorges reservoir area. And some development strategies of sweet orange are made according to the division.
Agricultural environment information monitoring instruments based on integrated intelligent sensors
Guoqing Yu Sr., Zhanyou Sha, Mingwei Cai
With the rapid development of facility agriculture in rural areas in China, the technology reform related to the auxiliary facilities has become the key factor to promote its development. And how to acquire the agricultural environment information effectively and rapidly becomes the most important factor. This article is aimed to make a study on the technical project of developing high performance and low cost environment monitoring instruments based on integrated intelligent sensors, which includes relative humidity/temperature monitor, intelligent turbidity sensor system with Microprocessor( μC) and single-bus interface and smog auto-detection and alarm system. The monitoring instruments can be applied to the overground information collecting, processing and alarming in greenhouses, poultry houses, livestock stables and so on.
Study on strain sensing of asymmetric Mach-Zehnder fiber filter
Chunyu Liu, Hongan Ye
An asymmetric Mach-Zehnder fiber filter was used as a substitute for fiber Bragg grating sensor, in order to solve the problem of cross-sensitivity between strain and temperature, while the characteristics of wavelength encoding were retained. In this paper, sensing characteristics of an asymmetric Mach-Zehnder fiber filter was analyzed theoretically. The result showed that the frequency separation of an asymmetric Mach-Zehnder fiber filter had a nearly linear relationship with the strain pressed on it. This conclusion had been verified by experiments. In our experiment, a cantilever beam was employed to tune strain on the asymmetric Mach-Zehnder fiber filter. Changing of frequency separation was used to describe the size of the strain. When variation of strain was about 1300 με, the changing of frequency separation would be about 6 THz. While, when temperature varied between 20°C and 70°C, the changing of frequency separation would not more than 0.02 THz. The structure of strain sensors had the advantage of wavelength encoding. At the same time; temperature change on the effects of strain sensing had been eliminated. It could be used for fiber-optic sensor to measure strain changes.
Discussion of GPS/RTK in fighting drought
Qinglin Wang, Liwei Fang, Kezhao Li
In this spring, the worst drought to hit China's northern wheat-growing belt in half a century. How to make proper decision to fight drought is a vital problem to Chinese government. Of course, this is a complicated problem for many factors involved. But for surveyor, we must provide the drought area, different drought levels and position information quickly. Real Time Kinematic (RTK) satellite navigation is a technique used in land survey and in hydrographic survey based on the use of carrier phase measurements of the GPS, GLONASS and/or Galileo signals where a single reference station provides the real-time corrections of even to a centimetre level of accuracy. In this paper, we discuss the application of GPS technology in fighting drought. Firstly, we introduce the RTK technology and its applications in other field. Secondly, according to the requirement of fighting drought, we give the scheme of how to get the information of drought area, different drought levels rapidly. Thirdly, we discuss the technology of real-time positioning to artificial rainfall using aeroplane.
Numerical modeling and analysis of the environment in a mechanically ventilated greenhouse
Fei-qing Wu, Li-bin Zhang, Fang Xu, et al.
Multi-span Greenhouse cooling in summer is always a problem for the greenhouse industry in china, to solve this, the key is to accurately predict the distribution and change of greenhouse environment. At present, the influence of mechanical ventilation about a Venlo-type glass greenhouse on environment has not been reported. The environment model, which takes into account solar radiation, is modeled and the temperature change & distribution is numerically simulated in a mechanically ventilated greenhouse using CFD(Computational Fluid Dynamics),then the velocities and temperatures at key points are measured in a Venlo-type greenhouse. By comparing, the velocity error and the relative error is controlled in 0.08m/s and 7% , respectively. and the temperature error and the relative error is controlled in 2 degrees and 5% expect the individual, respectively. Although the values between simulated and measured have some errors, the curve trend shows that CFD simulation on the mechanical ventilation is effective. It will provide a theoretical basis on greenhouse structure optimization and energy saving in future.
Research on the relationship between soil erosion and landscape pattern in the Wuyuer River basin based on GIS
Wenjuan Wang
In recent years, soil erosion has been an increasing concern in the Black Soil Area of Northeast China because of its harm to the marketable grain basis in China. Taken Wuyuer river basin in Black Soil Area of Northeast China as study area, Using GIS, RS and USLE, by choosing the reasonable calculating methods to get each factor in the USLE, we evaluated the soil erosion of this basin in 2005a. Otherwise, chosen the 48 subbasin as basic analysis units, with the spatial analysis ability of GIS and FRAGSTAT software, it get the soil erosion modulus and corresponding landscape pattern metrics in each subbasin. Base on these data, the relationship between soil erosion and landscape pattern was analyzed and the result can provide suggestion for landuse planning and soil erosion control. It shows that middle and upper reaches of Wuyuer river basin is the main erosion region, and its mean soil erosion modulus is 258.85t/(km2•a), which is higher than the tolerable soil loss rate in Black Soil Area of Northeast China. This region needs erosion control urgently. Correlation analysis shows a positive correlation between percentage of landscape(PLAND) of cropland, grassland, Perimeter-Area Fractal Dimension (PAFRAC), Shannon's Diversity Index (SHDI) and soil erosion modulus; Percentage of landscape(PLAND)of forest land as well as Contagion Index(CONTAG) show negative correlation with erosion modulus. With further analysis, it concludes that regulating the landscape pattern in cropland, grassland and forestland reasonably is very important for the soil erosion control and management.
Algorithm research showing high-dynamic GPS software receiver
Na Wei
In the paper, it completed the hardware platform of software receiver making use of TMS320C6713, GP2010 and GP2021. Comparing to the system based on the core of TMS320C32 when the other hardware, software and performance index unchanged, the idleness of this system has improved from 13% to 67%. As for the software, the algorithms choosing of acquisition, code tracking and carrier tracking and the relation between the parameters and dynamic performance of GPS receiver have been studied in the paper. Moreover, the experimental results indicated the positioning precision of this GPS receiver could amount to 15m under the condition that the velocity, accelerator, change rate of accelerator and data update rate of carrier were 12km/s, 10g, 10g/s and 10Hz respectively.
Interpolation and fitting algorithms for GPS satellite orbit
Hui Hu, Lian Fang
The paper used the fitting methods of Lagrange interpolation, Chebyshev polynomial fitting and Hermite interpolation to fitting the orbit based on broadcast ephemeris, then compared these results with the orbit of extrapolation, which indicated the Chebyshev polynomial fitting got the best precision, the Lagrange interpolation was inferior and the Hermite Interpolation was worst in the condition of same order. And the most precisions of the three above-mentioned algorithms were amount to the meter levels of 10-6, 10-5, and 10-3 respectively. However in consideration of operating time, the Lagrange Interpolation could get the fastest, the Chebyshev polynomial fitting was inferior and the Hermite interpolation was the slowest. And the average operating time of the three above-mentioned algorithms were 6 seconds, 146 seconds, and 260 seconds respectively.
Discrete Hadamard transformation algorithm's parallelism analysis and achievement
Hui Hu
With respect to Discrete Hadamard Transformation (DHT) wide application in real-time signal processing while limitation in operation speed of DSP. The article makes DHT parallel research and its parallel performance analysis. Based on multiprocessor platform-TMS320C80 programming structure, the research is carried out to achieve two kinds of parallel DHT algorithms. Several experiments demonstrated the effectiveness of the proposed algorithms.
Temporal and spatial changes analysis of arable land in Zhongshan city based on GIS and RS
Yuan Fang
Land use change is the most significant aspect in the research field of globe changing. Affected by both of natural and artificial factors, the land use and land resources quality varied continually. Zhongshan City where the zone has a typical feature of land use change and significant ecological effects is selected as a case. Applying the satellite images of Landsat-TM and the integrating techniques of RS and GIS, this paper analyzed the temporal and spatial processes and the spatial conversion of arable land in Zhongshan City from 1988 to 2002. The classified results of multi-temporal TM remote sensing image data and transfer matrix of land use show that land use has been changed significantly from 1988 to 2002 in Zhongshan City. Various types of land use converted frequent, which mainly reflects in the waters, the cultivated land loss and construction land increase. After 1995 land use degree of the study area grows slower, which shows Zhongshan City emphasized the overall development after the rapid expansion. The arable land area reduces rapidly and experienced rapid change under the pressure of urban expansion. It is the main period about the arable land to reduce from 1988 to 1995. More than 70 percent of arable land is converted to construction sites. Other types of lands also are converted to the arable land, which waters and the forest land were the major types.
Land use conversion and gravity center analysis in the coastal area of the Pearl River Estuary based on GIS and RS
Hui Zhang
Land use change is the hottest issue in the research field of globe changing. The Coastal Area of the Pearl River Estuary (CAPRE) where the zone has a typical feature of land use change and significant ecological effects is selected as a case. Applying the satellite images of Landsat-TM and the integrating techniques of RS and GIS, the present study analyzed the temporal and spatial processes and gravity center change in the Coastal Area of the Pearl River Estuary from 1988 to 2002. The classified results of multi-temporal TM remote sensing image data and transfer matrix of land use revealed that land use had been changed significantly from 1988 to 2002 in the Coastal Area of the Pearl River Estuary. Various types of land use convert frequently, which mainly reflect in the waters, the cultivated land loss and construction land increase and their different direction migration of the gravity center. After 1995 land use degree of the study area grows slower, which shows the Coastal Area of the Pearl River Estuary emphasized the overall development after the rapid expansion. On the east of the Coastal Area of the Pearl River Estuary the land use change which has experienced more rapid change represented the overall trend.
Analysis of construction land expansion during the urbanization process in Dongguan city
Ding-xue Wu
This paper takes Dongguan City as an example, which is one of the most important cities in Pearl River Delta. First, data on the variation of construction land in Dongguan are obtained by employing the statistic and analytic function of construction of GIS on the spatial data from remote sensing image data in different periods. Then the characteristics of construction land expansion are identified by using several methods in analyzing the spatial-temporal features of Dongguan City from 1988 to 2002, which include expansion area, expansion speed, expansion intensity index and transformation matrix index. The driving force of construction land expansion and its comprehensive evaluation are given in this paper by using social economical data and correlation analysis. The results obtained show that, during the last 15 years, the area of construction land has almost been obvious during the 1988~1995 period. The growth in different districts was obviously diversified and the main directions of City expansion are northeast and southwest; more arable land and developing land were occupied by construction land expansion. The economic growth is the decisive factor influencing the urban construction land expansion, and the correlative policies direction the economic growth run through the urban growth from beginning to end.
Asynchronous web geological map tag system based on Ajax
Linfu Xue
Ajax is a new WEB developing technology occurred in recent years, which implements the asynchronous interaction between the browser and the Web server. Most Web Geological Map System adopts traditional B/S synchronous interaction technology. Users have to face at the problem of browser congestion caused by the large-volume data of geological map transmitted on network. Applying the technology of Ajax to the Web Geological Map System, the author implements the asynchronous interaction between the browser and the Web geological map server. Compared with traditional Web Geological Map System of B/S synchronous mode, the system avoids putting a computational burden on the browser and keeps the response time short to provide a higher level of interaction. In addition, the author extends the function of tag management, which enhances the convenience of the system and makes the map management more perfect. The introduction of the concepts of role and privilege improves the security of the geological map information greatly.
The application of ESDA and GIS in analysis of regional rural economic
Wei-hua Liao
This paper introduced basic theory of global and local spatial autocorrelation analysis of Exploratory Spatial Data Analysis(ESDA), and analysis the application of ESDA method for regional rural economic. it is investigated the spatial dynamics of regional disparities at the county (city) level in Guangxi by analyzing rural per capita net income data in 2007, with the support spatial statistical analysis module of ArcGIS. Empirical results show that the overall county(city) level spatial disparities of rural per capita net income in Guangxi is great in 2007, and the global Moran'S I is 0.44051, which indicates that there are significant positive spatial autocorrelation. That is, the relatively high(1ow) developed county tends to be located nearby other high(1ow) developed counties more often than expected due to random chance. Local Moran's I scatterplot and LISA (Local Indicators of Spatial Association) cluster map have been used to test the local pattern of the Guangxi rural economic development.
GIS-based quality analysis on the cultivated land resources in poor areas of China
Ying Jie Wang
Cultivated land resource is a key factor that affects the development standard of a region. By analysis of land use and land cover data in 2000, together with national geographical data, soil fertility comprehensive quality assessment data (1980), a GIS-based research is carried out on the quality analysis of cultivated land resources in poor areas. Firstly, data mining methods are used to gather the inter-relationships between the poor areas' cultivated land resources and its geographical background factors. Secondly, comparative analysis between the poor areas and non-poor areas is conducted to reveal the difference. Results show that the big difference exists in the basic natural features of the cultivated land resources between poor and non-poor areas. Although the quantity of cultivated land resource in those poor areas is not less than that of non-poor areas, the quality is lowly evaluated because of its high elevation, steep slope and earth surface roughness. Finally, after overlay analysis, the natural quality of cultivated land resources in poor areas is assessed according to their topographical and soil fertility features.
GIS-based poverty and population distribution analysis in China
Jing Cui, Yingjie Wang
Geographically, poverty status is not only related with social-economic factors but also strongly affected by geographical environment. In the paper, GIS-based poverty and population distribution analysis method is introduced for revealing their regional differences. More than 100000 poor villages and 592 national key poor counties are chosen for the analysis. The results show that poverty distribution tends to concentrate in most of west China and mountainous rural areas of mid China. Furthermore, the fifth census data are overlaid to those poor areas in order to gain its internal diversity of social-economic characteristics. By overlaying poverty related social-economic parameters, such as sex ratio, illiteracy, education level, percentage of ethnic minorities, family composition, finding shows that poverty distribution is strongly correlated with high illiteracy rate, high percentage minorities, and larger family member.
The principle and main structure design on national database of poverty, environment, and development in China
Yingjie Wang, Xiangfeng Feng
Poverty is listed as the one of eight "Millennium Development Goals" by UN Summit. From 1978 to 2004, rural poverty population in China is cut to 26.1 million from 250 million. In order to support the decision maker to make nice planning in elimination of poverty and promotion of regional sustainable development in China, the GIS based systemic and comprehensive database for poverty, environment and development is proposed and designed in the paper. Additionally, the design principle and main content of the database is discussed by utilization modern technology, such as spatialtemporal and tree-ring data models for data structuring and coding, in order to represent current poverty status, spatial distribution and temporal variations, and to explore the relationship among poverty, environment and development ultimately.
The design and research of poverty alleviation monitoring and evaluation system: a case study in the Jiangxi province
Hong-yuan Mo, Ying-jie Wang, Zhuo-yuan Yu
The Poverty Alleviation Monitoring and Evaluation System (PAMES) is introduced in this paper. The authors present environment platform selection, and details of system design and realization. Different with traditional research of poverty alleviation, this paper develops a new analytical geo-visualization approach to study the distribution and causes of poverty phenomena within Geographic Information System (GIS). Based on the most detailed poverty population data, the spatial location and population statistical indicators of poverty village in Jiangxi province, the distribution characteristics of poverty population are detailed. The research results can provide much poverty alleviation decision support from a spatial-temporal view. It should be better if the administrative unit of poverty-stricken area to be changed from county to village according to spatial distribution pattern of poverty.
Development of a distributed agricultural drought prediction model based on TOPMODEL and GIS
Jingwen Xu, Wanchang Zhang, Changquan Wang, et al.
Drought disasters occur frequently in eastern China and are typical in China and even in the world. Severe droughts seriously affect the agricultural production, social and economic development, ecology and human life. In this paper, a new agricultural drought prediction model was developed based on GIS technology and TOPMODEL, which is a physically based watershed hydrological model that simulates the variable-source-area concept of stream-flow generation and has been widely used to study a variety of research areas. In this study, the original TOPMODEL was extended to be a distributed hydrological model. The watershed is divided into a number of regular grids, corresponding to the grids of DEM, and each grid is viewed as a sub-basin. So the surface runoff production was calculated at each grid. The runoff at each grid is routed along the stream flow direction to the main watershed outlet respectively at different velocity depending on the slop of this grid and watershed-average routing velocity. The soil moisture is predicted using the new distributed hydrological model. Finally, drought prediction is conducted by combining the predicted soil moisture and drought indices. The new model was tested in Linyi watershed, Shandong province, China. The results show that the model performs well in agricultural drought prediction.
Development of a soil moisture prediction model based on Xinanjiang model and GIS
Jingwen Xu, Wanchang Zhang, Changquan Wang, et al.
Soil moisture conditions are very important in agriculture - they control crops growth and development and are used directly to assess irrigation needs for a variety of crops. In this paper, a new soil moisture prediction model was developed based on GIS technology and the hydrological model Xinanjiang, which has been successfully and widely applied in humid and semi-humid regions in China since its development. The original Xinanjiang model uses a single parabolic curve to represent the spatial distribution of the soil moisture storage capacity over the catchment, where the exponent parameter b measures the non-uniformity of this distribution. It was extended to be a distributed hydrological model by using GIS technology. The watershed is divided into a number of regular grids, corresponding to the grids of DEM, and each grid is viewed as a sub-basin. So the surface runoff production was calculated for each grid. The runoff in each grid cell is routed along the stream flow direction to the main watershed outlet respectively at different velocity depending on the slop of this grid and watershed-average routing velocity . The soil moisture is predicted using the new distributed hydrological model. The new model was tested in Linyi watershed, Shandong province, China. The results show that the soil moisture predicted by the new model agrees with the field observed.
Study on temporal variation and spatial distribution for rural poverty in China based on GIS
Xianfeng Feng, Xiuli Xu, Yingjie Wang, et al.
Poverty is one of the most serious challenges all over the world, is an obstacle to hinder economics and agriculture in poverty area. Research on poverty alleviation in China is very useful and important. In this paper, we will explore the comprehensive poverty characteristics in China, analyze the current poverty status, spatial distribution and temporal variations about rural poverty in China, and to category the different poverty types and their spatial distribution. First, we achieved the gathering and processing the relevant data. These data contain investigation data, research reports, statistical yearbook, censuses, social-economic data, physical and anthrop geographical data, etc. After deeply analysis of these data, we will get the distribution of poverty areas by spatial-temporal data model according to different poverty given standard in different stages in China to see the poverty variation and the regional difference in County-level. Then, the current poverty status, spatial pattern about poverty area in villages-level will be lucubrated; the relationship among poverty, environment (including physical and anthrop geographical factors) and economic development, etc. will be expanded. We hope our research will enhance the people knowledge of poverty in China and contribute to the poverty alleviation in China.
Study on the shelterbelt effects on crop condition using RS and GIS
Rongxin Deng, Shuwen Zhang, Ying Li, et al.
The Northeast shelterbelt is a part of the Shelter Forest System Program in Three-North Regions of China, and the Jilin Province is an important food production basis, the research on the shelterbelt effects on crop condition in this region is very necessary to evaluating the protective effect and crop increasing. For this purpose, it choose Dehui, Yushu, Fuyu and Nong'an of the Jilin province as the research areas, and select the shelterbelt protected ground and no shelterbelt protected ground as the research spot respectively, taken the MODIS NDVI of 16 days compositional data productions from March to October in 2008, using GIS analysis technique, analyzing the crop condition in this temporal series. Through comparing the NDVI temporal changing line, peak value and the sum of the NDVI, it found that the shelterbelt has an obvious effect on the crop condition. It can conclude that, through reducing the wind speed, changing the local climate environment, the shelterbelt can improve the crop condition. In addition, comparing to the traditional research methods, it's much more effective, and less time consuming to analyzing the shelterbelt by RS and GIS, and it can help study the shelterbelt's protective effect on a larger temporal and spatial scale.
The choice of adjustment programmes of China's existing coal mine safety supervision system
Yong-Liang Liu, A-Hong He
At present, China's coal mine safety supervision system adopted in the form of management functions, mosts of rights of central government were decentralized to the locals,which unable to carry out effective supervision of coal mines, resulting in frequent accidents. This paper first discussed the status of China's coal mine safety supervision system; then analyzed the problems existing in the supervision system ,based on these, further presented the perfecting and choice of adjustment programmes of China's coal mine safety supervision. Finally, after comparing the adjustment programmes, adopted "adjust the current supervision system, strengthen vertical management mode of the State Administration of Coal Mine Safety", the author tried to put forward some solutions to China's coal mine safety supervision system.
A CMOS low-power voltage control oscillator applied in the GPS RF receiver
Zhi-min Cai, Xiao-fang Chen
The VCO circuit is widely applied in various communication circuits. This paper describes a low power ring voltage control oscillator. The VCO consists of five stages, and each stage uses differential structure. The VCO is the single-ended output. The chip is fabricated in 0.18μm CMOS technology of TSMC in Taiwan. The chip core area is 0.25mm × 0.05mm. Measurements show that the power consumption is about 9.2mW at a supply voltage of 1.75V. The center frequency is 62MHz. The phase noise is -89.39dBc/Hz@1MHz. The VCO can be used in PLL of the GPS RF receiver.
Gray-Markov-model-based prediction and analysis on urban water use
Yuanbiao Zhang, Jianwen Xie
This paper develops a Gray-Markov model-based approach to predict the municipals water use by combining the grey system theory and Markov random process theory. The proposed approach uses the prediction curve of the grey dynamic forecast model GM(1, 1) as the datum line of the trend of the city water use. Besides, the Markov prediction approach is applied to determine the range of the system chance fluctuation, optimize and modify the grey predictive value. To demonstrate that our system is working correctly, the author used the prediction system to analyze the water data and predict the volume of water use in the city of Zhuhai at a specific time. The approach can not only effectively discover the overall trend of the city water use, but also overcome the influence of the chance fluctuation upon the precision of prediction. Therefore, the approach is effective in real world.
Evaluation of heavy metal accumulation in greenhouse soils in Shenyang, Northeast China
Jun Wang, Xin Chen, Yi Shi, et al.
Soil heavy metals are considered being originated from two major sources, natural and anthropogenic. With the spring-up of greenhouse farming in the suburbs of big cities, heavy metals accumulation in greenhouse soil is becoming a serious environmental problem. In order to evaluate and ascertain the accumulation status and origins of heavy metals in the greenhouse soils of Shenyang suburb, the Cu, Zn, Cd, As, Cr and Pb contents in soil samples collected from the greenhouse fields with different cultivation years were determined by using atomic absorption spectroscopy (AAS) and hydrogen-atomic fluorescence spectrometer (HG-AFS), and the origins of these heavy metals were analyzed by employing correlation analysis, principle component analysis (PCA) and hierarchical cluster analysis (HCA). No obvious soil heavy metals accumulation was observed, but the Cu, Zn, Cd and As contents in greenhouse soils increased with increasing years of cultivation. Two significant components were extracted by PCA, explaining 70.013% of total variance. The Cu, Zn, Cd and As in test soils were mainly associated with anthropogenic input, whereas Cr and Pb were related to parent rocks. HCA confirmed and completed the results obtained by PCA, classifying the data in two groups representing different origins. Cluster included Cu, Zn, Cd and As representing human inputs, while Cluster included Cr and Pb representing natural sources. Moreover, the results obtained by the correlation analysis also agreed with PCA and HCA, also helping in elucidating the relationship between heavy metals and soil properties. More attention should be paid to the anthropogenic inputs of Cu, Zn, Cd and As in Shenyang greenhouse fields, especially for those having been cultivated for 5 years or more.
Driving force analysis of LUCC and forecast method based on remote sensing in coal mining area
Hong-quan Xie, Xiang-wei Gao, Xia Lu
Guye District in Tangshan City was a study case in this paper, taking three temporal(1987, 1992 and 2001) remotely sensed imageries as data resource, and imageries were pretreated by ENVI and interpreted by human-computer interaction, three land use/cover classification data of remotely sensed imageries were obtained. Based on collecting lots of correlative information, the qualitative analysis for driving force of LUCC in Guye District from 1987 to 2001 was done from five aspects, which were economic development, population increase, coal mining, land reclamation, and political and economic policy. Principal component analysis was carried out using the software SAS8.1. We took economic data as base, and chose six analytical factors. The result illustrated that the main driving forces of LUCC in Guye District were economic development, coal output, and political and economic policy. According to Markov mode, the future LUCC structure was forecasted using MATLAB based on the transfer matrix of three stages and the LUCC data in 1987 and 1992. The prediction result showed that the forecasting result using different stages conformed to area change trends of corresponding stages.
A multivariable approach for land cover mapping with MODIS data: an assessment of Sanjiang Plain, China
The objective of this study was to present the improvement of land cover mapping of Sanjiang Plain using MODIS data. A filter method based on time series was applied to remove EVI noise. A set of variables that were derived from MODIS data and DEM consisted of:(i)phenological feature variables derived from EVI temporal profile;(ii)geographical environment variables;(iii)spectral feature variable obtained from MODIS surface reflectance data;(iv)several feature band variables. Then the land cover map was generated using a simple but reasonable decision tree. In addition, our classification result was compared with land use map derived from Landsat ETM+ images using a confusion matrix, as well as a comparison with MODIS-IGBP land cover product was discussed. The comparison demonstrated the good behavior of the multivariable approach and technical processing used in the research, as well as indicated the promise of MODIS data for land cover mapping at regional scale.
The spatial-temporal change and forecast of farmland landscape in Shenyang city based on GIS and RS
Rui Zhou, Yue-hui Li, Yuan-man Hu, et al.
With the pressure on ecological environment from rapid urbanization and decreasing farmland becoming more and more concerned in the world, especially in developing countries, such as China, the spatial-temporal change of farmland, even the change trends in the future, should be analyzed and forecasted to serve for regional and national social, economic and environmental sustainable development in the long future. Based on the multi-temporal remote sensing images, RS and GIS spatial analysis technology, this paper used transfer matrix method to identify mutual-transformation quantity among various land-use types from 1988 to 2004, chose 6 representative landscape metrics to analyze the overall farmland landscape pattern, utilized orientation azimuth and buffer analysis method to quantify spatial-temporal characteristics of farmland dynamic degree (Df) in different direction and distance from city center, then selected Markov model to forecast the land-use development and variation tendency reasonably. The results showed that the conversion from farmland to built-up area was the most important characteristics of land-use change in Shenyang city, the fragmentation and complication of farmland landscape became more obvious with fast urbanization and industrialization, and the landscape dominance of farmland was being weakened, the maximum of farmland dynamic degree located in the west region of Shenyang, and the high speed change of farmland concentrated on 4 to 6 km away from city center, the area of farmland will continuously decrease in the future according to the result of the model of Markov process.
Estimation methods for GPS kinematic data processing
Gang Chen, Xiong Pan
The characteristics of three GPS kinematical data processing models, Least Square, Kalman filtering, and Semiparametric model are discussed and their advantages and disadvantages are compared. With observational data and pertinent data processing software, the applicable condition, context and effect of the three models are experimented. Results show that when the mobile platform is in uniform motion, the accuracy of the three models are almost equal; when the mobile platform is in stochastic acceleration, the accuracy of Semiparametric model is superior to that of LS, and that of Kalman filtering is the worst.
Research on agricultural ecology and environment analysis and modeling based on RS and GIS
Wensheng Zhang, Hongfu Chen, Mingsheng Wang
Analysis of agricultural ecology and environment is based on the data of agricultural resources, which are obtained by RS monitoring. The over-exploitation of farmlands will cause structural changes of the soil composition, and damage the planting environment and the agro-ecosystem. Through the research on the dynamic monitoring methods of multitemporal RS images and GIS technology, the crop growth status, crop acreage and other relevant information in agricultural production are extracted based on the monitor and analysis of the conditions of the fields and crop growth. The agro-ecological GIS platform is developed with the establishment of the agricultural resources management database, which manages spatial data, RS data and attribute data of agricultural resources. Using the RS, GIS analysis results, the reasons of agro-ecological destruction are analyzed and the evaluation methods are established. This paper puts forward the concept of utilization capacity of farmland, which describes farmland space for development and utilization that is influenced by the conditions of the land, water resources, climate, pesticides and chemical fertilizers and many other agricultural production factors. Assessment model of agricultural land use capacity is constructed with the help of Fuzzy. Assessing the utilization capacity of farmland can be helpful to agricultural production and ecological protection of farmland. This paper describes the application of the capacity evaluation model with simulated data in two aspects, namely, in evaluating the status of farmland development and utilization and in optimal planting.
Land use/cover change and its driving forces analysis during the last 50 years in the Three Gorges Reservoir area: a case study in the Wanzhou District
Wei Xian, Huaiyong Shao, Wancun Zhou, et al.
Based on topographic maps (1:50 000 in scale) in 1953, MSS images in 1972, TM images in 1986, 1995 and 2000, the dynamic evolution process of land use during lately 50 years in Three Gorges Reservoir Area were analyzed. And the driving forces about the dynamic change of land use in the study area were discussed. The results showed that the structure of LUCC in the study area has changed obviously during lately fifty years, the areas of woodland and grassland reduced while the areas of cultivated land and construction land were respectively increased. From land use / cover changes of time and space in the landscape pattern, the natural landscape types continuous shrink. The number of forest patches decreased and its concentration in space was obvious. The trend of Shrub, woodland and grassland was fragmentized. Policy, economic development and population growth were the main driving factors affecting land use change in the study area.
A study on eco-environmental vulnerability of mining cities: a case study of Panzhihua city of Sichuan province in China
Huaiyong Shao, Wei Xian, Wunian Yang
The large-scale and super-strength development of mineral resources in mining cities in long term has made great contributions to China's economic construction and development, but it has caused serious damage to the ecological environment even ecological imbalance at the same time because the neglect of the environmental impact even to the expense of the environment to some extent. In this study, according to the characteristics of mining cities, the scientific and practical eco-environmental vulnerability evaluation index system of mining cities had been established. Taking Panzhihua city of Sichuan province as an example, using remote sensing and GIS technology, applying various types of remote sensing image (TM, SPOT5, IKONOS) and Statistical data, the ecological environment evaluation data of mining cities was extracted effectively. For the non-linear relationship between the evaluation indexes and the degree of eco-environmental vulnerability in mining cities, this study innovative took the evaluation of eco-environmental vulnerability of the study area by using artificial neural network whose training used SCE-UA algorithm that well overcome the slow learning and difficult convergence of traditional neural network algorithm. The results of ecoenvironmental vulnerability evaluation of the study area were objective, reasonable and the credibility was high. The results showed that the area distribution of five eco-environmental vulnerability grade types was basically normal, and the overall ecological environment situation of Panzhihua city was in the middle level, the degree of eco-environmental vulnerability in the south was higher than the north, and mining activities were dominant factors to cause ecoenvironmental damage and eco-environmental Vulnerability. In this study, a comprehensive theory and technology system of regional eco-environmental vulnerability evaluation which included the establishment of eco-environmental vulnerability evaluation index system, processing of evaluation data and establishing of evaluation model. New ideas and methods had provided for eco-environmental vulnerability of mining cities.
A GIS-based model for estimating regional potential evapotranspiration in complex terrains
Xin-yao Zhou, Yong-hui Yang, Xiao-hua Hao
The estimation of regional reference evapotranspiration (ET0) is crucial for agricultural water assessment. Traditional methods based on point-specific ET0 from meteorological stations are not suitable for complex terrains. Advances of GIS technology provide such possibility. For very complex terrains, however, topography can have considerable effect on meteorological factors such as air temperature and solar radiation. In this paper, spatially distributed daily ET0 was estimated by FAO Penman-Monteith equation, while the effect of topography on meteorological factors was taken into consideration. This was achieved through spatial interpolation of maximum and minimum air temperature, wind speed, relative humidity and sunshine hours. Solar radiation was modeled at grid level by adjusting the effect of specific site conditions prior to estimating ET0. To test the reliability and applicability of the model, spatial distribution of ET0 (resolution 90 × 90 m) was generated for taking Fengning County of North China as an example. There was a good agreement between the site conditions and model simulated ET0. This study demonstrates the possibility of incorporating topography in the estimation of ET0.
A novel dual module remote video monitoring system based on TD-SCDMA and CDMA2000 1X
Zengshan Tian, Qin Zhang, Wei He, et al.
A novel dual module remote video monitoring system is designed and realized in this paper, which is based on TDSCDMA and CDMA 2000 1X wireless networks. The key technologies of designing and realization are presented in detail. In addition, test results show that the proposed system efficiently uses wireless channel resources and improves transmission rate. Compared to traditional single module video monitoring system, our designed system can provide a better performance in real-time property and stability.
Ecological landscape classification and dynamic change mapping in the Taoer River basin, Northeast China
Jiuchun Yang, Shuwen Zhang
Ecological landscape classification (ELC) plays a significant role in sustainable planning and management of natural resources from large scales to fine scales, because it provides an understanding of ecosystem with a holistic concept by linking biotic and abiotic factors together. In this research, Taoer River basin of Northeast China was taken as a typical study area, for its present situation of environment is imperiling the regional sustainable development, with rapid salinization expansion in midstream and downstream especially. A hierarchical system with four levels of landscape ecoregion, landscape ecocatena, landscape ecosection and landscape ecotope was adopted, and the components of ecosystem used to delineate ecounits of each level include climate normals and hydrological data across nearly 50 years, lithology data in 1:500000 scale, soil data in 1:1000000 scale, topographic factors and landform data from SRTM DEM in 90m resolution, and vegetation and land use and land cover data from Landsat remotely sensed images of 1976 and 2000 by interactive interpretation method. Through spatial overlay and geographical relationship analysis methods with the support of GIS technique, each specific level of details was presented with a series of maps. And based on the dynamic factors, mainly referring to climate and land use and land cover, the dynamic change maps from 1976 to 2000 were produced to analyze the environmental evolutive process.
Effects of tillage on the Fe oxides activation in soil
Guangyu Chi, Xin Chen, Yi Shi, et al.
Since mid-1950s, the wetland ecosystems in Sanjiang Plain of Northeast China have been experiencing greater changes in land use, which had negative effects on the soil environments. This study assessed the effects of soil tillage on the activation of soil Fe in the region. The test ecosystems included natural wetland, paddy field and upland field converted from wetland. Soil samples at the depths of 0-10 cm, 10-20 cm, 20-30 cm, 30-40 cm, 40-60 cm, 60-90 cm and 90-120 cm were collected from each of the ecosystems for the analysis of vertical distribution of soil pH, organic carbon, chelate Fe oxides and Fe(II). The results showed that the conversion of wetland into paddy field and upland field induced a decrease of organic carbon content in 0-10 cm soil layer by 61.8% (P <0.05) and 70.0% (P < 0.05), respectively. The correlations among iron forms and soil organic carbon showed that chelate Fe oxides and Fe(II) was correlated positively with soil organic carbon and chelate ratio had a more positive relationship with organic carbon than chelate Fe oxides and Fe(II). The results of chelate Fe oxides, Fe(II) and chelate ratio of Fe suggested that reclamation could prevent the Fe activation and organic matter is credited for having an important influence on the process of Fe activation.
Analysis on the rural house reconstruction agreement in earthquake disaster rural areas
Wenwu Zhao, Haiyan Xu, Yinhui Zhang, et al.
The rural house reconstruction is one of the key issues for the disaster areas reconstruction. Base on the field research in Sichuan disaster areas, this paper took the "rural house reconstruction agreement" as a target, discussed its theoretical effects and practical application, and provided several policy recommendations for the existent problems.
Land resources and sustainable utilization in China
Wenwu Zhao, Haiyan Xu, Guanghui Jiang, et al.
Land resources are the one of the key resources for human society development. This paper analyzed the current situation and problems of land use in China, and discussed sustainable utilization strategic mode of land resources. And the strategic measures of sustainable utilization of land resources in China includes establishing an approach focused on the sustainable development, ensuring the total dynamic balance of cultivated land, scientifically optimization, innovating the land property rights management and protecting the environmental resources and et al.
Assessment of ecological footprint of land use in Chongqing, China
Ming Li, Baizhan Li
The land use in China has an important impact on environment and the Chinese economic development. The sustainable development has been recognized as the key element to keep China's development with success in the future. This paper uses ecological footprint and biological capacity as indicators to measure regional sustainable degree of land use. The ecological footprint and the biological capacity of land use in Chongqing municipality with 28 million populations have been calculated from 1999 to 2007. The ecological footprint and the biological capacity of land use in Chongqing municipality had obvious changed from 1999 to 2007. The change degree of ecological footprint affected by land use is more prominent than the change degree of biological capacity. The fossil energy land possesses the most proportion, which exceeds 58% in average. The cropland is also an important effect to ecological footprint, which achieves to 35% in proportion. The results from the research can inform the Chongqing municipality government in more detail enhances the land protection in the balance of urban development with society, ecology, environment and resource.