Assessing optical earth observation systems for mapping and monitoring temporary ponds in arid areas

Remote sensing methods for locating and monitoring temporary ponds over large areas in arid lands were tested on a study site in Northern Senegal. Three main results are presented, validated with field data and intended to highlight different spectral, spatial and temporal characteristics of the methods: (1) Among several water indices tested, two Middle Infrared-based indices (MNDWI—Modified Normalized Difference Water Index and NDWI₁—Normalized Difference Water Index) are found to be most efficient; (2) an objective method is given prescribing the necessary sensor spatial resolution in terms of minimal detected pond area; and (3) the potential of multi-temporal MODIS imagery for tracking the filling phases of small ponds is illustrated. These results should assist in epidemiological studies of vector-borne diseases that develop around these ponds, but also more generally for land and water management and preservation of threatened ecosystems in arid areas.     

A global map of rainfed cropland areas (GMRCA) at the end of last millennium using remote sensing

The overarching goal of this study was to produce a global map of rainfed cropland areas (GMRCA) and calculate country-by-country rainfed area statistics using remote sensing data. A suite of spatial datasets, methods and protocols for mapping GMRCA were described. These consist of: (a) data fusion and composition of multi-resolution time-series mega-file data-cube (MFDC), (b) image segmentation based on precipitation, temperature, and elevation zones, (c) spectral correlation similarity (SCS), (d) protocols for class identification and labeling through uses of SCS R²-values, bi-spectral plots, space-time spiral curves (ST-SCs), rich source of field-plot data, and zoom-in-views of Google Earth (GE), and (e) techniques for resolving mixed classes by decision tree algorithms, and spatial modeling. The outcome was a 9-class GMRCA from which country-by-country rainfed area statistics were computed for the end of the last millennium. The global rainfed cropland area estimate from the GMRCA 9-class map was 1.13 billion hectares (Bha). The total global cropland areas (rainfed plus irrigated) was 1.53 Bha which was close to national statistics compiled by FAOSTAT (1.51 Bha). The accuracies and errors of GMRCA were assessed using field-plot and Google Earth data points. The accuracy varied between 92 and 98% with kappa value of about 0.76, errors of omission of 2–8%, and the errors of commission of 19–36%.     

The Application of GIS in Education Administration: Protecting Students from Hazardous Roads

Though enrolment by proximity is an official educational policy in Iran, the lack of clearly defined school attendance areas has resulted in an informal open enrolment system where parents may choose public schools outside their residential areas. Two major consequences of parental choice are longer commutes to schools and increased use of motor vehicle transport. To delineate school attendance areas for public female junior high schools in the city of Rasht in Northern Iran, this research used the multiplicatively weighted Voronoi diagram (MWVD) technique to construct school attendance areas. The approach was shown to be useful in developing countries like Iran where accident fatalities are not only disproportionately high but the public school system lacks sufficient educational diversity to offset the societal costs of opting out of neighbourhood schools. A GIS-based specialist package was used for constructing the proposed school attendance areas. Given the MWVD utility in demarcating spaces so that all journeys within them are closest to a chosen point, the research concluded that proposed school attendance areas can result in shorter and more convenient commutes on foot for students. This can eliminate the need to travel by vehicle for the overwhelming majority of students and thus make their journeys more convenient and safer.     

地震属性法在南黄海北部盆地勘探新区烃源岩厚度预测中的应用

新区、深层和深水等低勘探程度地区是今后油气勘探的重要方向,而烃源岩厚度预测则是沉积盆地勘探新区烃源岩评价的重要问题。以南黄海北部盆地勘探新区东北凹陷的烃源岩早期评价为背景,基于地震反射特征追踪东北凹陷内烃源岩的发育层位和空间展布研究成果,首次应用地震属性方法对东北凹陷的主力烃源岩(上白垩统泰州组和古新统阜宁组)厚度进行了初步预测,并结合地震速度岩性分析法对本区泰州组烃源岩厚度的预测结果加以验证。结果表明南黄海盆地东北凹陷泰州组烃源岩较阜宁组烃源岩分布广且厚度大,西次洼为东北凹陷主力生烃洼陷。地震属性法是沉积盆地勘探新区内定量化预测烃源岩厚度的一种行之有效的新方法,其对于类似盆地勘探早期的烃源岩评价研究也具有非常重要的借鉴意义。     

Artisanal fishing areas and traditional ecological knowledge: The case study of the artisanal fisheries of the Patos Lagoon estuary (Brazil)

One hundred and twenty-four fishing areas were identified and georeferenced according to fishermen's traditional ecological knowledge. Nearly 80% of the designations of the fishing areas were known by fishermen only and are registered for the first time. Fishermen identify fishing areas according to depth, wooden logs used to anchor fixed nets, gradation of water transparency, and traditional use of certain areas. This study reveals the richness of knowledge held by fishermen, it illustrates their solid straight relationship with the natural environment where they live, and shows the potential uses of TEK for fisheries management.     

Endangered species, threatened fisheries: Science to the rescue! Evaluating the Congressionally designated Steller Sea Lion Research Program

Between 2001 and 2004, the US Congress designated over $120 million for research on the western population of Steller sea lions. This paper evaluates the science program, summarizing its context and motivation, the amount and distribution of funds, and how the recipients allocated funding to research activities. It considers factors affecting the science program's contribution to solving the problem that spurred Congress to act. While the program failed to achieve its immediate goals for a variety of reasons, it did provide long-term benefits for science and ecosystem management in the North Pacific.     

海域使用权立体分层确权及管理配套制度探讨

由于社会经济的不断发展和科技的快速进步,我国对海域空间资源的开发利用已从二维平面转向三维立体空间开发,但随之也对我国海域空间范围界定和权属管理提出了更高的要求。文章从海域立体空间分层特性出发,对我国海域使用权立体分层确权的内涵、基本原则、考虑因素进行了深入剖析,并对我国海域三维立体开发利用中面临的困境和管理配套制度的设计进行了综合探讨。研究结果表明：海域空间可以分为水面上方、水面、水体、海床和底土5个部分,海域使用权立体分层确权则是在同一海域多层次利用中,对基于特定功能用途所占用的特定海域空间开展使用权确权的过程,在海域使用权管理的过程中,必须构建和完善海域空间三维产权法律制度体系,以确保海域使用权立体分层确权的实施。     

西昌盆地白果湾组致密砂岩油气形成关键指标评价与有利区优选

综合钻井、大量实测剖面、样品测试分析和区域地质资料,对西昌盆地白果湾组烃源岩生烃强度、镜质体反射率、砂岩储层物性等关键指标进行了系统评价.西昌盆地上三叠统白果湾组主要油气储层类型为中-粗砂岩,有利层段主要发育在白果湾组一段、三段和四段,砂岩具有中孔低渗、区域分布广、厚度大等特征,ZD-1井揭示砂岩含油气性好.西昌盆地白...