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从景观生态学构建城市旅游开发与规划的操作模式 总被引:13,自引:0,他引:13
本文尝试建立一个关于旅游开发与规划的应用理论模式,以兼顾理论的抽象性和操作性。模式的构建依据地理空间分析方法,同时借用景观生态学斑、廊、基的概念。文中详细论述了该斑廊基网络结构操作模式的基本特点、变换空间分析方法等运行机制,并以不同城市旅游规划、设计实例说明三大操作块的功能和操作意义。 相似文献
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Daisuke Tsumune Jun Nishioka Akifumi Shimamoto Shigenobu Takeda Atsushi Tsuda 《Progress in Oceanography》2005,64(2-4):111
The first iron (Fe) – fertilization experiment in the western North Pacific was carried out using SF6 to trace the Fe-fertilized water mass. A solution in 10,800 liters of seawater of 350 kg of Fe and 0.48 M of SF6 tracer was released into the mixed layer over a 8 × 10 km area. On the first underway transects through the patch after the Fe release, we observed a significant increase of dissolved Fe (ave. 2.89 nM). The fertilized patch was traced for 14 days by on-board SF6 analysis. A Lagrangian frame of reference was maintained by the use of a drogued GPS buoy released at the center of the patch. The patch moved westward at a rate of 6.8 km d−1. Mixed layer depth increased from 8.5 to 15 m during the experiment. Horizontal diffusivity was determined by the change of SF6 concentration in the patch. The horizontal diffusivity increased during the experiment. We evaluate here the fate of Fe in a Fe-fertilized patch using the dilution rate determined from sulphur hexafluoride (SF6) concentration. Dissolved Fe concentrations subsequently decreased rapidly to 0.15 nM on Day 13. However, the dissolved Fe half-life of 43 h was relatively longer than in previous Fe-enrichment studies, and we observed a larger increase of the centric diatom standing stock and corresponding drawdown of macro-nutrients and carbon dioxide than in the previous studies. The most important reason for the larger response was the phytoplankton species in the western North Pacific. In addition, the smaller diffusivity and shallower mixed layer were effective to sustain the higher dissolved Fe concentration compared to previous experiments. This might be one reason for the larger response of diatoms in SEEDS. 相似文献
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Restoring degraded landscapes in lowland Namaqualand: Lessons from the mining experience and from regional ecological dynamics 总被引:4,自引:1,他引:4
Three-quarters of a century ago diamond mining was added to livestock grazing and cereal cropping as a serious cause of landscape degradation in the north-western semi-arid region of South Africa, Namaqualand. Since that time the activities of diamond mine operators and prospectors have eclipsed all other land uses as a cause of degradation in this region. Discontinuous patches along virtually all of the 400 km of the Namaqualand coastline have been, or are currently, being mined or prospected. Prior to 1992 little was done to restore the landscapes and ecosystems to their pre-mining state, but since then legislation has placed a clear responsibility for restoration on mining operators. Implementation of ecological restoration was initially slow, but has recently gained momentum, in line with a growing awareness of environmental responsibilities amongst the global mining industry. In general, autogenic recovery of the perennial vegetation does not take place. The low annual rainfall and prevailing strong windy conditions present the greatest climatic challenges to the restoration of the flora. While the unique vegetation, and its features (e.g. poor representation of perennial species in the seedbank) present challenges to understanding the interventions that are critical in achieving ecological restoration. At the same time, climatic conditions such as the strong seasonality and low variability of rainfall, together with floristic features such as the high incidence of succulence, and the extraordinary drought tolerance of many seedlings, present opportunities for restoration. Perhaps the greatest challenges to restoration derive from the unsuitability of much of the mined overburden soils for plant growth. The nature and importance of climatic conditions, mined soils, topsoils, soil nutrients, landscaping, seedbanks, seeding, transplantation, and the interactions between these and other factors are evaluated in the context of this semi-arid environment and the prevailing mining practices. 相似文献
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Linking individual behavior to spatial population processes, may clarify the complex link between species distribution and landscape properties. We asked how shrubs affect beetles in drylands and tested if we could explain distribution patterns of beetles by individual response to shrub landscape. We studied patch preference of ground-dwelling beetles segregated in a two-phase mosaic landscape, composed of shrub-covered and open patches and hypothesized that species richness and abundance are higher under shrubs due to the ameliorated microclimatic conditions and greater food resources. Pitfall trapping showed that shrub patches were preferred in shrub poor ecosystem because there was more food available under shrubs and cooler temperatures. However, similar conditions resulted in shrub preference only in an arid ecosystem, whereas in a semi-arid ecosystem, with high cover of shrubs, we found more beetles in the open patches. Observations in beetle movement patterns explained the contradicting effects of shrub patches in the two ecosystems. Beetle movement was affected by shrubs’ shading suggesting dependency on shrub structure rather than speciesdependency. Integrating analysis of beetle distribution in the population level with analysis of individual movement provides a robust framework for linking landscape properties to species behavior and distribution in a patchy landscape. 相似文献
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滑动方向相反的含障碍体平行断层失稳破坏应变场变化特征的研究 总被引:4,自引:0,他引:4
通过对滑动方向相反的含障碍体平行断层失稳破坏岩石破裂实验的应变场时空分布特征的分析,探讨了岩石破坏过程和破坏方式。并且通过对平行断层和障碍体破坏所产生的相互作用和影响的分析,进一步研究了这种滑动方向相反的含障碍体平行断层失稳破坏的增、减震机制,结果表明是一种互为增震机制。最后通过数值模拟技术对实验的破坏过程进行了模拟,证明了实验结果与数值模拟结果一致,说明实验结果具有可靠性。 相似文献
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用于台风定位的雷达回波拼图方法 总被引:1,自引:1,他引:1
本文采用斜轴等距离方位投影作为拼图底图的投影,选择需要的邻近若干部雷达进行拼图,也可以任选区域进行雷达拼图。这种投影底图不但使原来在单部雷达上有效的台风定位方法得以继续使用,而且提出了雷达对台风的探测范围和精度。经95年业务使用结果表明,对业务工作有一定参考价值。 相似文献
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福建森林植被景观空间格局分异研究 总被引:13,自引:0,他引:13
本文从景观的概念出发,以地理信息系统为支撑手段,开发了空间信息数据库以记录分析福建森林植被景观的块斑,不规划性及景观总体特征,通过定量分析福森林植被的空间格局,说明福建森林植被景观受物理,生物以及社会和经济参数的制约情况,空间数据的对比序列表明,参数中某些参数值存在着空间差异,会导致福建森林景观的变化。 相似文献
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