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41.
海南岛东南海岸带景观生态规划 总被引:3,自引:0,他引:3
对海南岛东南海岸带进行了景观生态规划。根据海南岛东南海岸带的自然资源条件与经济运行特点,将研究区划分为4个生态区:近岸热带海洋旅游区;海水养殖区;海岸平原粮牧生态区;生态林业区。各区的生态与社会经济特征不同,在利用与管理各生态区的过程中应该采取不同的对策措施,即加强宣传教育与宏观管理,以重点项目建设为契机,加快生态经济建设,优化生态经济结构。建立生物多样性管护区。 相似文献
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Quantitative study of landscape patterns in homogenous carbonate rock distributed regions in Guizhou
Qiu TAN Shijie WANG Yangbing LI 《中国地球化学学报》2006,25(B08):174-175
With the utilization of GIS software, research is conducted on (a) the characteristics of cells, fragmentation, and patch fractal of landscape based on homogenous carbonate rocks in Guizhou; (b) causes of the formation of these characteristics. It has been found that under the influence of lithology, the landscape of the study region as a whole shows consistency, yet embodies distinct diversity inside. The consistency is embodied in the following aspects: (a) the preponderant landscape consists of bushes and small woods; (b) secondary landscape is characteristic of forests and grounds covered with grass; (c) of all the patches making up the study area small patches are in the majority, with positive-skewed distribution of patches-as a result, steep peaks are characteristic of the charts showing the distribution of patches. The factor of scale is not taken into account in the study of patches. The shapes of patches tend to be regular with strong disturbances from human activities, and consequently, the values of fractal dimensions of landscape types tend to get smaller. The fragmentation of patches is more apparent in landscape under influence of human activities than the one without these disturbances. Compared with regions characteristic of homogenous dolomite, the characteristics of homogenous limestone areas are described as follows: (a) low utilization rate of water resource; (b) uneven distribution of diversified landscape; (c) weak resistance against disturbances from human activities; (d) the continuous degradation, ever-increasing fragmentation, intensification of spatial heterogeneity, and the deteriorating stability of landscape. 相似文献
44.
本溪地质遗迹与地质公园的开发建设 总被引:1,自引:0,他引:1
本文比较详细的说明了本溪地区存在的地质遗迹,并进一步论述了本溪地质遗迹的特征及保护现状,提出了开发建设本溪地质公园的设想,这对本溪地区旅游资源的保护及旅游业的发展有着十分重要的意义。 相似文献
45.
Y.T. John Kwong 《中国地球化学学报》2006,25(B08):229-230
Naturally acidic drainage associated with pyritic black shale has been observed in many locations in the Yukon Territory. While not necessarily linked to known mineral deposits, most of these natural acid rock drainage occurrences show elevated dissolved concentrations of trace elements, especially zinc, nickel, copper, cadmium and arsenic. Based on field observations, microbial investigation, chemical analyses and geochemical modeling, the fate and transport of potentially deleterious elements at two natural acid drainage occurrences with slightly different settings are examined. The Macintosh Creek is a small, acidic stream (pH 2.98-3.40), 2 km long, located in the Macmillan Pass area of east-central Yukon amidst known sedimentary exhalative massive sulfide mineralization but remains undisturbed by exploration activities. Its trace metal content is apparently derived from groundwater discharges, which gave as much as 5.0, 2.5, 0.7, 0.13 and 0.03 mg/L ofZn, Ni, Cu and As, respectively. Interaction and sorption reactions with algal mats, biofilms and iron oxyhydroxides appear to be the dominant mechanisms attenuating aqueous contaminant transport along the stream. Cryogenic precipitation further consolidates the ferricrete formation and reduces the mobility of the sorbed metals. The tributaries of the Engineering Creek along the Dempster Highway in northern Yukon drain through a series of dolomite, phyllite, argillite, limestone, black shale, sandstone and conglomerate with no known concentration of mineralization. In this area, the water chemistry fully reflects the local geology with acidic streams invariably associated with black shale occurrences. Groundwater seeps in the headwaters area of the km-180 Creek completely enclosed in black shale gave pH 3.0 and as much as 148, 39, 2.9 and 9.1 mg/L of Zn, Ni, Cu and As, respectively. Sorption with iron oxyhydroxide and organic matter appear to dominate the attenuation of contaminant transport along the stream. However, once entered into carbonate-dominated terrains, secondary carbonate minerals exercise additional geochemical control on the local water chemistry as a result of neutralization. 相似文献
46.
1990~2005年间,是广州市经济快速发展和城市景观变化最大的时期,以同时段TM影像解译得到广州市的土地覆被类型图,从数量结构、空间信息及位置转移和景观等方面,分析了广州市土地覆被的动态特征.数量结构的研究结果显示:在快速城市化过程中广州市的耕地、林地等自然资源的利用程度在加大,自1995年起,这种变化的趋势开始减缓;土地覆被类型之间的信息与位置的转移变化频繁,并且表现出空间位置分异的特征.景观特征指数分析结果表明:广州市城市土地覆被向破碎化方向发展,城市建设用地呈扩展之势. 相似文献
47.
First- and second-generation migrants represent about 40 per cent of the Australian population. With such a large and also diverse immigrant population, urban landscapes are significantly shaped by the gardens created by migrants. Two groups of Vietnamese and Greek migrants, in the inner suburb of Marrickville South in Sydney, were interviewed to examine the relationship between migration history and garden-making practices. Garden composition was influenced by migrants’ relationship with their homeland, in terms of length of time since migration, previous garden ownership, reason for migration and desire for cultural continuity, and by the size of the garden. Gardens also varied according to country of migration. The actual garden produce and type of environment created by the garden helped to emphasise and maintain cultural relationships, provide a space of nostalgia, and give a sense of ownership and control. 相似文献
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49.
Landscapes change in complex ways, creating surface patterns reminiscent of forms seen through a kaleidoscope. On the Earth's surface, those forms are linked to, and caused by, processes that originate with bedrock‐soil‐vegetation‐atmosphere interactions. Human‐caused alterations to landscapes are additionally tied to socioeconomic processes. Evaluation of landscape‐level processes can benefit from examining (1) the influence of disturbance regimes in altering landscape patterns, (2) the importance of considering surficial processes, (3) the subtle and cryptic spatial relations that may be present, (4) the reciprocal relationships among local processes and regional consequences, (5) the increased likelihood of some land cover transitions compared to others, and (6) the special case of landscapes with long histories of human use. These are all examples of potential fruitful arenas for interactions and represent a path for expansion of landscape ecology through accommodation of a broad range of content covered by the international GIScience community. 相似文献
50.
Andrew Sluyter 《Geographical review》2006,96(3):361-381
ABSTRACT. While in New Spain from 1803 to 1804, Alexander von Humboldt interacted with some of its landscapes and the texts that represented them. Analysis of those interactions regarding the Basin of Mexico and the Gulf lowlands demonstrates what purely text‐based studies of the production of places cannot: The contrasting landscape elements and patterns that had emerged over millennia during precolonial times in those two places, their relative degrees of depopulation during the colonial era, and the relative degrees of rigor Humboldt applied to interacting with the resulting landscapes and the texts that represented them greatly affected his representations of those places in his 1811 Essai politique sur le royaume de la Nouvelle‐Espagne. His representations of the precolonial Basin of Mexico as productively developed and of the precolonial Gulf lowlands as pristine have influenced the transformations of those places in the two centuries after New Spain became the Mexican republic through its wars of independence (1810–1821). 相似文献