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The accuracy of InSAR baseline measurement or estimation is the key factor of digital elevation model (DEM) generation. A new method of baseline estimation about Newton iteration method was presented in terms of the principle of SAR interferometry. The issue of baseline computation can be examined using the ERS-1/2 C wavelength single look complex (SLC) of April 15 and 16 in 1996, Its validity is...
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...
To acquire the planted acreage of major grain crops and their spatial distribution in an timely, accurate, quantitative and periodic way is of significance for making a socio-economic development plans at various levels of government, and improving the operational management for relevant enterprises and farmers. The National Bureau of statistics of China (NBS) aims to take the fully advantages of...
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...
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)...
The estimation of soil organic matter (SOM, %) is an important issue for agricultural production, but common methods for estimating the SOM is very expensive and time-consuming. Recently, hyperspectral diagnosis technology has showed great potential in measuring SOM due to its rapid, nondestructive, reproducible and cost-effective characteristics, thus four common spectral analysis methods had been...
FY-3A is a polar-orbiting meteorological satellite launched by China in 2008 which carries Medium Resolution Spectral Imaging (MERSI). This paper used 250m FY-3A/MERSI 10-day composite Normalized Differential Vegetation Index (NDVI) time series to estimate the winter wheat acreage in 10 provinces in northern China. Eleven time series from October 2010 to January 2011 are collected and reconstructed...
The aim of the paper is to discover the spatial distribution of agricultural mechanization and investigate the possible influential factors of spatial disparities of agricultural mechanization in China. The statistic data at provincial-level in the year of 2009 were collected to achieve the objective. Method of exploratory spatial data analysis (ESDA) is applied to examine the spatial structure and...
Land cover area estimation is one of the obvious applications of remote sensing. This paper compared two categories of area estimators, the confusion matrix calibration and the regression estimators, under various sample sizes and classification accuracy. Based on the relationship between the error distribution and heterogeneity of remote sensing data, simulation procedure was conducted to acquire...
This study aims to examine the suitability of Globcover land cover dataset for its accuracy in mapping and monitoring cropland in Northeast China three provinces. To do so, Globcover dataset was compared with the reference national land cover dataset 2000 (NLCD-2000) for assessing the aggregated area and spatial extent of cropland across the study area. The results showed that the accuracy in Jilin...
The Leaf Area Index (LAI) was an important structural parameter for quantifying the energy and mass exchange characteristics in ecosystems. There was considerable interest in assessing LAI to evaluate crop growth and production. In this study, hyperspectral vegetation indices (VIs) from in-situ remote sensing measurements were utilized to monitor erect-type corn (Zea mays L.) canopy's LAI. Firstly,...
Crop growth stage is important information for decision making in many related agricultural sectors. In-time accurate estimation of crop growth stage is desired. Kernel-fitting of time series vegetation indices have shown potential in estimating crop growth stage while tolerant to noisy data and missing data. The challenge to apply such models is dealing with current year when incomplete data are...
Forest height is one of the important ecological elements and its estimation has been developed recent years. Forest height estimation is usually obtained through the scattering centers between canopy and ground using Pol-InSAR data. There are three classes of method for forest height estimation, phase-difference between interferograms, coherence optimization based on coherent / incoherent scattering...
Crop development information is critical to U.S. agricultural economy and decision making. In this paper, a general framework of Hidden Markov Models (HMMs) based corn progress percents esitmation method has been presented. Multivariate time series involving mean NDVI, fractal dimension, and Accumulated Growing Degree Days (AGDDs) are embedded into the modified HMM. Features of mean NDVI and fractal...
This paper proposes a new automated USDA National Agricultural Statistics Service (NASS) Cropland Data Layer (CDL) based method for stratifying U.S. land cover. The proposed method is used to stratify the NASS state level Area Sampling Frames (ASFs) by automatically calculating percent cultivation at the Primary Sampling Unit (PSU) level based on the CDL data. The CDL based stratification experiment...
Estimating crop leaf area index (LAI) based on remotely sensed observations is a normal way for regional crop monitoring and yield estimation in precision agriculture. However, the spatial heterogeneity in crop canopies and the nonlinearity of model for LAI estimation make differences between estimated-upscaled LAI (baseline data) and upscaled-estimated LAI. Then, aiming to reduce these differences,...
The length of the crop season is a major determinant of yields in Sahel. Based on green-up onset detection derived from MODIS time series, this paper proposes a new methodology for the estimation of the sowing dates. It builds upon a novel stochastic model that translates vegetation onset detections around villages into sowing probabilities. Results for Niger show that this approach outperforms the...
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