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Establishment biomass monitoring methods of invasive species has an important instructive meaning for control and treatment of invasion, which was also beneficial to national ecological safety and social stability. This study researched the estimation methods of biomass of water hyacinth by hyperspectral remote sensing. The spectral reflectance characteristics were analyzed based on field experiments...
China southwest region has suffered from three years of severe drought in the dry season from 2010 to 2012, with devastating impacts on agricultural productions. Previous agricultural cropping patterns were adjusted to adapt to drought. How to find evidences of agricultural adaption to drought? Here, we showed agriculture adaptation to drought stress according to the changes of vegetation greenness,...
In present paper, to effectively improve the accuracy of burnt scar mapping in hilly areas, a new method by combing multiple spectral indices with Support Vector Machines (SVM) has been put forward. Firstly, the Landsat TM image was geometrically and atmospherically corrected. Secondly, two widely used thematic-oriented spectral indices, namely, the vegetation index SAVI and the water index MNDWI...
How to evaluate all sorts of heterogeneously online geospatial web resources (e.g., OGC web services, online geospatial data) as a top-to end operational unit is a main geospatial research topic in this period. The cloud computing technology is the infrastructure to use internet and central remote servers to organize all kind of computational Web resources as a service. This technology allows for...
Dynamic monitoring crop growth can keep track of the crop growth status, seedlings, soil moisture, nutriture and their changes and then the appropriate management strategies will be taken to ensure timely the normal growth and development. This study represented the potential of satellite hyperspectral imagery to monitor winter wheat biophysical and biochemical characteristics through narrow-band...
An Extended Support Vector Machine (ESVM), which could improve the conventional change detection methods by purifying thematic classification results and neglecting of the side effect by mixed pixel, is proposed for crop acreage measurement by multi-temporal remote sensing land cover change. The ESVM method combines the concept of hard and soft classification and divides the study objects into winter...
In this study, we evaluated the precision of different regression models correlating grasslands aboveground biomass (AGB) and its corresponding vegetable index (VI). We further identified changes in the size and distribution of AGB and explored the relationships between interannual AGB pattern and climatic factors in the eastern Inner Mongolia grasslands by integrating AGB data collected from 520...
Numerous mixed pixels from coarse resolution data and missing date from moderate resolution data are major concern in cropland identification. Therefore, estimation using combining the coarse time series data and moderate resolution data has become the popular tendency for cultivated area identification. We proposed a novel method which integrated the coarse time series and moderate resolution data...
Heading stage is the key stage of corn in whole growth phase, degree of corn tasseling directly related to the yield and quality in heading stage. Remote sensing data in the reflective optical domain function as a unique cost-effective source for providing spatially and temporally distributed information on key biophysical and biochemical parameters of vegetation. Based on remote sensing data to acquire...
Leaf water content (LWC) is an important parameter for evaluating crop health and predicting crop yield. The objective of this study was to compare two methods for the precision of estimating LWC in winter wheat by combining stepwise regression method and partial least squares (SRM-PLS) or PLS based on the relational degree of grey relational analysis (GRA) between water vegetation indexes (WVIs)...
Field surveys were conducted at regreening, jointing, heading and flowering stage in Jiangsu in 2011. The HJ satellite images were downloaded and preprocessed. Wheat grain quality was acquired at maturity. Band values of sampling sites were derived from the satellite images of four growth stages by using GPS information, and the candidate vegetation indices were calculated with the band values. The...
In regional scale, satellite data was gained frequency nearly a day or more shorter, and these satellite data had already been wildly used for drought monitoring. Meanwhile, a variety of information systems of drought monitoring based on client/server architecture were developed and employed. However, these systems were too professional for non-professional workers to use. With the development of...
Unique polarimetric information included in SAR data hasn't received deserved attention, especially in the retrieval of crops biophysical parameters. This paper finds that two polarimetric parameters, that is polarimetric scattering entropy (H) and mean scattering angle (α), have great potential in crops biophysical parameters retrieval. Polarimetric features extracted by eigenvector-based and model-based...
Precision nitrogen (N) management requires real-time diagnosis of crop N status, and recommends N application rates accordingly. Nitrogen nutrition index (NNI) has been proposed as a better indicator of crop N status, but it is not suitable for practical applications, because it requires destructive plant sampling and time-consuming analysis of plant N concentration. There has been increasing interest...
The normalized difference vegetation index (NDVI) time-series data, derived from satellite sensors, has been used to support land cover change detection and monitor crops successfully, but further applications are hindered by residual noise in the NDVI data. Methods for reducing noise and constructing high-quality NDVI time-series data sets can be broadly grouped into three general types, including...
Radar data has important implications in agricultural fields monitoring, particularly in the retrieval of the crop height, leaf area index (LAI) and soil moisture information. The objective of this study was to estimate soil moisture contents based on multi-polarized synthetic aperture radar (SAR) data acquired over wheat fields. The soil moisture inversion algorithm was based on semi-empirical backscattering...
Vegetation Health Index is computed based on the vegetation index and land surface temperature which are very important satellite products for drought monitoring with remote sensing. The quality of Temperature Condition Index and Vegetation Health Index deeply depends on the quality of the Land Surface Temperature (LST). The present retrieval algorithm of Moderate Resolution Imaging Spectroradiometer...
Land surface temperature (LST) is a key parameter in ecological and farm environment studies. The study area is located in Zhangye of Gansu province, mainly was covered by crops and desert. To retrieve LST from ASTER thermal infrared (TIR), split window algorithm was used. Surface emissivity and atmospheric transmittance was estimated previously. To evaluate the estimated result, the ASTER and MODIS...
The fraction of absorbed photosynthetically active radiation (FPAR) is a key biophysical variable that can be used to derive agronomic information for crop condition monitoring and yield prediction. Vegetation indices have been proved to be a useful method for FPAR estimation. However, most vegetation indices have their own limitations and can decrease the sensitivity to FPAR. The object of this study...
As a case study on analysis of soil erosion change, in Hulunbeir, Inner Mongolia, China, was once one of the most severely eroded regions in semi-arid and semi-humid China. However, its soil erosion is becoming a matter of concern for more and more people in recent years. The main body of vegetation is Daxinganling virgin forests and Hulunbeir grassland, However, large areas of forest were destroyed...
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