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面向海洋渔业决策支持的信息综合协调研究 总被引:2,自引:1,他引:1
时空信息与社会行业非空间信息的综合是资源环境研究和管理的发展方向之一。该文就研究成果阐述基于信息综合的海洋渔政支持系统及其构造,系统有机综合了地理信息系统(GIS)、全球定位系统(GPS)、管理信息系统(MIS)等技术,对时空信息和社会行业信息进行有机的综合,实现对海洋渔政事务的自动协调处理,进而对渔业多源信息进行综合协调,为海上渔业指挥和调控提供决策支持,从而保障渔业生产安全和资源的可持续利用。 相似文献
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东海区鱼类资源变化GIS时空分析 总被引:15,自引:0,他引:15
以东海区分小渔区分天分网型的捕捞量统计数据为样本数据,计算出资源密度的时空分布数据,并结合地理信息系统技术对这一时空数据进行时空分析,对东海区的中上层鱼类资源和底层及近底层鱼类资源的空间展布作分析,可以看到资源分布的块状和带状特征,以及资源分布与水文环境的关系,最后,对每个渔区11年资源密度进行趋势分析发现,11年来大部分渔区的资源密度呈下降趋势,小部分渔区的资源密度呈上升趋势。 相似文献
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案例推理从20世纪90年代初在人工智能领域兴起,在各个领域得到了广泛的发展.由于地理现象的复杂特性,许多现象发生的本质或机理还有待探索,其定量化的模拟和预测还不成熟,因此应用案例推理成为地学数据定量分析的新方法.但地理案例自身特殊的时空特征决定了地理案例的推理方式不同于传统的方式,需要考虑案例自身或者案例之间时空上的相互依赖关系.本文在分析地理案例时空分布特征的基础上,给出了案例推理的地学推理模式. 相似文献
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An abrupt ice and snow storm disaster which occurred in the spring of 2008 se-verely destroyed forests over a surprisingly large portion of southern China. A transectcrossing Jinggang Mountain-Jitai Basin-Yushan Mountain-Wuyi Mountain was selected as the study area. The authors integrated field data collected in two field surveys to analyze the impacts of the disturbance on forests. The following results were obtained. (1) The extent of damage to plantations along the transect decreased in the order of slash pine > masson pine > mixed plantation > Chinese fir. Slash pine is an introduced species from southern America which is characterized by fast growth, low wood quality and rich oleoresin, and showed a damage rate of 61.3% of samples, of which 70.4% cannot recover naturally. Masson pine is the native pioneer species of forests with harder wood, and 52.5% were damaged due to turpentine, of which 60.9% cannot recovery naturally. Chinese fir is a local tree species and samples showed a rate of 46% and a relative rate of 32.5%, lower than the mixed plantation.(2) From west to east along the transect, we can see that evergreen broad-leaved forest of the western transect on Jinggang Mountain showed the lightest damage extent, and a Cryp-tomeria plantation at an altitude of 700 m was severely destroyed while Chinese fir showed light damage below 700 m and relatively severe damage above 900 m. Masson pine and slash pine in the central transect in Jitai Basin were damaged severely due to turpentine ac-tivities, and closed natural secondary deciduous broad-leaved forest was damaged severely due to high ice and snow accumulation on intertwined shrubs. Masson pine aerial-seeding plantations below 400 m along the eastern transect in Xingguo and Ningdu counties were nearly undamaged for small tree sizes, and Chinese fir at 500-900 m altitude showed a lighter damage extent. However, masson pine which was distributed above 400 m and planted in the 1960s, was severely damaged due to turpentine. 相似文献