Download or read book Evaluation of the Use of Remote Sensing Data to Identify Crop Types and Estimate Irrigated Acreage Uvalde and Medina Counties Texas 1989 Water Resources Investigations Report 92 4117 written by and published by . This book was released on 1992 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of the Use of Remote sensing Data to Identify Crop Types and Estimate Irrigated Acreage Uvalde and Medina Counties Texas 1989 written by Lee H. Raymond and published by . This book was released on 1992 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Water resources Investigations Report written by and published by . This book was released on 1992 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Open file Report written by and published by . This book was released on 1993 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Summary of Water resources Activities of the U S Geological Survey in Texas fiscal Years 1989 92 written by and published by . This book was released on 1993 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1993-05 with total page 1830 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1993-04 with total page 1118 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography of the Edwards Aquifer Texas Through 1993 written by and published by . This book was released on 1995 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recent Library Additions written by and published by . This book was released on 1992 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 1038 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Remote Sensing of Earth Resources written by and published by . This book was released on 1994 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1993 with total page 1290 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sections 1-2. Keyword Index.--Section 3. Personal author index.--Section 4. Corporate author index.-- Section 5. Contract/grant number index, NTIS order/report number index 1-E.--Section 6. NTIS order/report number index F-Z.
Download or read book Agrindex written by and published by . This book was released on 1994 with total page 860 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1993 with total page 988 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Remote Sensing of Irrigated Crop Types and Its Application to Regional Water Balance Estimation written by Tim R. McVicar and published by . This book was released on 2000 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Efficient Crop Type Mapping Based on Remote Sensing in the Central Valley California written by Liheng Zhong and published by . This book was released on 2012 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most agricultural systems in California's Central Valley are purposely flexible and intentionally designed to meet the demands of dynamic markets. Agricultural land use is also impacted by climate change and urban development. As a result, crops change annually and semiannually, which makes estimating agricultural water use difficult, especially given the existing method by which agricultural land use is identified and mapped. A minor portion of agricultural land is surveyed annually for land-use type, and every 5 to 8 years the entire valley is completely evaluated. So far no effort has been made to effectively and efficiently identify specific crop types on an annual basis in this area. The potential of satellite imagery to map agricultural land cover and estimate water usage in the Central Valley is explored. Efforts are made to minimize the cost and reduce the time of production during the mapping process. The land use change analysis shows that a remote sensing based mapping method is the only means to map the frequent change of major crop types. The traditional maximum likelihood classification approach is first utilized to map crop types to test the classification capacity of existing algorithms. High accuracy is achieved with sufficient ground truth data for training, and crop maps of moderate quality can be timely produced to facilitate a near-real-time water use estimate. However, the large set of ground truth data required by this method results in high costs in data collection. It is difficult to reduce the cost because a trained classification algorithm is not transferable between different years or different regions. A phenology based classification (PBC) approach is developed which extracts phenological metrics from annual vegetation index profiles and identifies crop types based on these metrics using decision trees. According to the comparison with traditional maximum likelihood classification, this phenology-based approach shows great advantages when the size of the training set is limited by ground truth availability. Once developed, the classifier is able to be applied to different years and a vast area with only a few adjustments according to local agricultural and annual weather conditions. 250 m MODIS imagery is utilized as the main input to the PBC algorithm and displays promising capacity in crop identification in several counties in the Central Valley. A time series of Landsat TM/ETM+ images at a 30 m resolution is necessary in the crop mapping of counties with smaller land parcels, although the processing time is longer. Spectral characteristics are also employed to identify crops in PBC. Spectral signatures are associated with phenological stages instead of imaging dates, which highly increases the stability of the classifier performance and overcomes the problem of over-fitting. Moderate accuracies are achieved by PBC, with confusions mostly within the same crop categories. Based on a quantitative analysis, misclassification in PBC has very trivial impacts on the accuracy of agricultural water use estimate. The cost of the entire PBC procedure is controlled to a very low level, which will enable its usage in routine annual crop mapping in the Central Valley.
Download or read book Estimating Water Use in the United States written by National Research Council and published by National Academies Press. This book was released on 2002-09-22 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: Across the United States, the practices for collecting water use data vary significantly from state to state and vary also from one water use category to another, in response to the laws regulating water use and interest in water use data as an input for water management. However, many rich bodies of water use data exist at the state level, and an outstanding opportunity exists for assembling and statistically analyzing these data at the national level. This would lead to better techniques for water use estimation and to a greater capacity to link water use with its impact on water resources. This report is a product of the Committee on Water Resources Research, which provides consensus advice to the Water Resources Division (WRD) of the USGS on scientific, research, and programmatic issues. The committee works under the auspices of the Water Science and Technology Board of the National Research Council (NRC). The committee considers a variety of topics that are important scientifically and programmatically to the USGS and the nation and issues reports when appropriate. This report concerns the National Water-Use Information Program (NWUIP).
