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An Improved ASTER Index for Remote Sensing of Crop Residue  [PDF]
Guy Serbin,E. Raymond Hunt,Craig S. T. Daughtry,Gregory W. McCarty,Paul C. Doraiswamy
Remote Sensing , 2009, DOI: 10.3390/rs1040971
Abstract: Unlike traditional ground-based methodology, remote sensing allows for the rapid estimation of crop residue cover (fR). While the Cellulose Absorption Index (CAI) is ideal for fR estimation, a new index, the Shortwave Infrared Normalized Difference Residue Index (SINDRI), utilizing ASTER bands 6 and 7, is proposed for future multispectral sensors and would be less costly to implement. SINDRI performed almost as well as CAI and better than other indices at five locations in the USA on multiple dates. A minimal upgrade from one broad band to two narrow bands would provide fR data for carbon cycle modeling and tillage verification.
Effect of Reduced Tillage and Crop Residue Ground Cover on Yield and Water Use Efficiency of Sorghum (Sorghum bicolor (L.) Moench) Under Semi-Arid Conditions of Ethiopia  [PDF]
Tewodrose Mesfine,Girma Abebe,Abdel-Rahman M. Al-Tawaha
World Journal of Agricultural Sciences , 2005,
Abstract: Reduced tillage and maintenance of ground cover with crop residues may increase water availability to the crop in semi-arid areas of Ethiopia. Conventional, tied-ridging and zero-tillage were compared with 0, 3 and 6 mg ha 1 of tef straw applied after tillage. The interaction of tillage and straw application rate was significant for grain yield with 70 and 46% increases in yield with 3 mg ha 1 of straw applied for conventional and zero tillage respectively, but yield with tied-ridging was not affected by straw application. The main effect of tillage on yield was not significant. Mean stover yield was also increased with straw application. Mean soil water throughout the season was nearly 20% more with tied-ridging than with other tillage practices and about 16% more with 3 mg ha 1 straw applied as compared to no straw applied. Grain produced per unit of water used increased linearly with straw application rate and was less for zero tillage and for tied-ridging or conventional tillage. Tied-ridging is the most promising tillage practice and ground cover with crop residues is necessary to achieve acceptable yield with zero tillage.
Extraction of structured vegetation cover index for Loess Area in North Shaanxi based on TM images

LEI Wan-ning,WEN Zhong-ming,

应用生态学报 , 2009,
Abstract: Based on the concept of structured vegetation cover index (Cs) and by using TM images as the information source, the extraction way of Cs for Loess Area in North Shaanxi by using remote sensing techniques was explored. In study area, Cs was better than the traditional projected vegetation overage index in expressing the relationships between vegetation structure and soil erosion. The Cs was closely related to the remote sensing vegetation indices, such as green indices NDVI (Normalized Difference Vegetation Index) and MSAVI (Modified Soil Adjusted Vegetation Index), and yellow indices NDSVI (Difference Senescent Vegetation Index) and NDTI (Normalized Difference Tillage Index). The combination of the green and yellow indices could better express the effects of vegetation on soil erosion, compared with the single index. Among these remote sensing vegetation indices, the MSAVI and NDTI could be the ideal green and yellow vegetation indices for the extraction of Cs from TM images. It was possible to extract the Cs from remote sensing data through the regression analysis of Cs and remote sensing vegetation indices. However, this method was just valid ated and applied to the study area. Whether it could be applied to other regions was needed to be further validated due to the phonological differences from one region to another.
Spectral Reflectance of Wheat Residue during Decomposition and Remotely Sensed Estimates of Residue Cover  [PDF]
Craig S. T. Daughtry,Guy Serbin,James B. Reeves,Paul C. Doraiswamy,Earle Raymond Hunt
Remote Sensing , 2010, DOI: 10.3390/rs2020416
Abstract: Remotely sensed estimates of crop residue cover (fR) are required to assess the extent of conservation tillage over large areas; the impact of decay processes on estimates of residue cover is unknown. Changes in wheat straw composition and spectral reflectance were measured during the decay process and their impact on estimates of fR were assessed. Proportions of cellulose and hemicellulose declined, while lignin increased. Spectral features associated with cellulose diminished during decomposition. Narrow-band spectral residue indices robustly estimated fR, while broad-band indices were inconsistent. Advanced multi-spectral sensors or hyperspectral sensors are required to assess fR reliably over diverse agricultural landscapes.
Effects of Tillage Systems on Wheat Yield and Residue in Turkey
Tayfun Korucu,Hasan Merdun
Journal of Animal and Veterinary Advances , 2012,
Abstract: The general objective of this study was to evaluate the effects of tillage systems on the wheat yield and residue in the first crop wheat planting. Specifically, the objective was to determine the annual gross production of wheat yield and residue used as animal feed and alternative raw material in the industry in overall Turkey. Wheat samples from five different points of each plot were harvested by hand using a frame of 0.5x0.5 m in order to calculate the amounts of grain yields and crop residues. After harvesting, the wheat yield and the amounts of stubble, chaff and straw were measured. The ANOVA test results indicated that while, the differences in the stubble amount among the treatments (tillage applications) were statistically not significant, the differences in the other parameters among the treatments were statistically significant at p = 0.01 level. The highest wheat yield (4943 kg ha-1), residue (2966 kg ha-1) and chaff (2704 kg ha-1) were obtained in the CP/CD treatment. When the estimated and measured values were statistically compared, the total residue had significant relationship at 0.05 level at only CP/CD treatment, but at 0.01 level at the all other treatments. The straw had significant relationship at 0.05 level at DP2/DD treatment, but at 0.01 level at the all other treatments. Using the data of the State Statistics Institute (DIE) in 2007, 8 million tons chaff and 8 million tons straw were estimated out of approximately 18 million tons total residue in overall Turkey.
Comparison and Analysis on Methods of Snow Cover Mapping by Using Satellite Remote Sensing Data

WANG Jian,

遥感技术与应用 , 1999,
Abstract: The three kinds of methods, such as training sites Supervised Classification (SC), Digital Numbers (DNs) statistics and Normalized Difference Snow Index ( NDSI) have been used to map snow cover distribution and then to calculate snow cover area. In this study, the remote sensing data sets from Landsat TM, Moderate Resolution Imaging Spectroradiometer(MODIS) and NOAA/AVHRR were selected to utilize for mapping snow cover since these images are most current remote sensing data to be
Predicting Species Cover of Marine Macrophyte and Invertebrate Species Combining Hyperspectral Remote Sensing, Machine Learning and Regression Techniques  [PDF]
Jonne Kotta, Tiit Kutser, Karolin Teeveer, Ele Vahtm?e, Merli P?rnoja
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0063946
Abstract: In order to understand biotic patterns and their changes in nature there is an obvious need for high-quality seamless measurements of such patterns. If remote sensing methods have been applied with reasonable success in terrestrial environment, their use in aquatic ecosystems still remained challenging. In the present study we combined hyperspectral remote sensing and boosted regression tree modelling (BTR), an ensemble method for statistical techniques and machine learning, in order to test their applicability in predicting macrophyte and invertebrate species cover in the optically complex seawater of the Baltic Sea. The BRT technique combined with remote sensing and traditional spatial modelling succeeded in identifying, constructing and testing functionality of abiotic environmental predictors on the coverage of benthic macrophyte and invertebrate species. Our models easily predicted a large quantity of macrophyte and invertebrate species cover and recaptured multitude of interactions between environment and biota indicating a strong potential of the method in the modelling of aquatic species in the large variety of ecosystems.
Effect of Land Cover Heterogeneity on Soil Moisture Retrieval Using Active Microwave Remote Sensing Data  [PDF]
Tarendra Lakhankar,Hosni Ghedira,Marouane Temimi,Amir E. Azar,Reza Khanbilvardi
Remote Sensing , 2009, DOI: 10.3390/rs1020080
Abstract: This study addresses the issue of the variability and heterogeneity problems that are expected from a sensor with a larger footprint having homogenous and heterogeneous sub-pixels. Improved understanding of spatial variability of soil surface characteristics such as land cover and vegetation in larger footprint are critical in remote sensing based soil moisture retrieval. This study analyzes the sub-pixel variability (standard deviation of sub-grid pixels) of Normalized Difference Vegetation Index and SAR backscatter. Back-propagation neural network was used for soil moisture retrieval from active microwave remote sensing data from Southern Great Plains of Oklahoma. The effect of land cover heterogeneity (number of different vegetation species within pixels) on soil moisture retrieval using active microwave remote sensing data was investigated. The presence of heterogeneous vegetation cover reduced the accuracy of the derived soil moisture using microwave remote sensing data. The results from this study can be used to characterize the uncertainty in soil moisture retrieval in the context of Soil Moisture Active and Passive (SMAP) mission which will have larger footprint.
Self-organization Neural Tree Model for Recognition about Land Cover Type of Remote Sensing

Cai Yudong,Li Wei,Xu Weijie,

遥感学报 , 1995,
Abstract: The self-organization neural tree for the recognition about land covertype of remote sensing was presented in this paper,which a group of samples wasstudied.The successful rate was high.The results show that the neural networkmodel was good,and therefore it might be referred as an effective technique forthe recognition about land cover type of remote sensing.
Land use/cover remote sensing based on hierarchical information extraction method in a county
分层信息提取法在县域土地 利用/覆被遥感中的应用

HU Zhao-ling,LI Zhi-jiang,DU Pei-jun,

地理研究 , 2009,
Abstract: It is important to achieve the qualitative and quantitative information of land use/cover in a county(or county-level city)of China with higher precision,which is helpful to enhance eco-environment protection and sustainable development of rural economy.Presently,remote sensing images of the medium and high resolution are mostly used to monitor the changes of land use/cover in a county.To make better use of remote sensing technology in monitoring land use change,it is necessary to improve the automatization...
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