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101.
景区周边环境范围定量界定—山岳型景区山西绵山实例研究 总被引:2,自引:1,他引:1
胡炜霞 《干旱区资源与环境》2010,(5)
随着旅游业的快速发展和城镇现代化的推近,景区周边涌现出了大量与景区不协调的问题,同时,由于人们对景区所处背景环境标准的提高,忽视周边环境与景区完整性的做法已不能适应新时代旅游者的需求。未来景区的竞争已延伸到景区周边环境范围。为此建议今后在景区规划工作中,亦应将制定科学详尽的周边环境保护整治规划放在重要位置,因此周边环境应有一个较为清晰的地域范围,以便于环境质量评价和规划运作,以及行之有效地落实周边环境调控。提出对景区周边环境地域范围定量界定的影响拐点法,并以绵山景区为例进行实证研究。结果显示景区能规划管理至定量方法所做的周边环境范围,无论对游客还是周边居民来说,满意度均较高。周边环境调控对于提高景区综合环境质量具有重要意义。 相似文献
102.
用山路引理得到了一类带有Dirichlet边值条件的p-Laplacian方程的非平凡解的存在性及多解性. 相似文献
103.
There are a series of city environmental problems especially in the mountain city along with the city fast development. In recent decade, many scholars have studied the urban heat island, the urban temperature, the urban wind field, the precipitation and the urban visibility etc. But the urban thermal environment has not been settled radically. All the measures have not been used in the practice. And the researches in thermal environment of the mountain cities are very few. So the authors consider Chongqing as the researching object. Chongqing is one of the typical mountain cities in the semi-tropical. Sequentially we find out the characteristic of the thermal environment in the mountain city. Further the authors seek for the measures to plan and build ecological city. They conclude that CFD can be used in the simulation of urban environment, and use the result of simulation in urban planning is possible. The thermal environment in the center of Chongqing needs to be improved. 相似文献
104.
Yu Zhuoqun 《保鲜与加工》1993,(4)
During the citified course at present for construction of old mountain cities is very important. This paper has analyzed the following problems: the contradiction for construction of cities, style of mountain cities, reconstruction of city construction and reflecting the features of our age from cities. 相似文献
105.
Interspecific F1 hybrids were produced after artificial intercrossing of six Sideritis species indigenous to Greece, namely: S. athoa, S. euboea, S. syriaca, S. raeseri, S. scardica, S. clandestina and a cultivated clone of S. raeseri. It was found that all species cross with each other, but the level of crossability varied with the cross-combination. In the yield evaluation experiments, the interspecific hybrids with a common female parent were considered as a group. It was observed that yield during the year of establishment was relatively low, but the interspecific hybrids out-yielded the control in both fresh and dry weight. All hybrids produced higher yields in the following years and their productivity started to decline after the fifth year. All hybrids produced higher yields than the control in all six years of the experiment. The highest yield over the years, in fresh and dry weight, was produced by the group Sideritis raeseri cultivated clone (cc) ×Sideritis spp. This yield, however, was not always significantly different from the yield produced by the second in the rank group (S. clandestina×Sideritis spp.). A high correlation (r > 0.99) between fresh and dry weight was observed. The two groups with the highest yield also had the highest essential oil content. In addition, all the interspecific hybrids had a higher essential oil content than the control species. Furthermore, the essential oil content of the selected individual hybrid plants ranged between the midparental value to a value higher than the high-parental species, indicating an additive and dominance gene action. It was also found that the content of the essential oil in the seven most important components (pinene, lemonene, cynene, menthone, copaene, caryophyllene and valerianic ester) varied from hybrid to hybrid. Given that Sideritis reproduces mainly asexually, the direct use of individual interspecific hybrids with higher yield and content in essential oil than the control species is possible in cultivation. 相似文献
106.
为避免山地果园单轨运输机运行时碰到前方穿越的移动物体或轨道上的静止障碍物,提高运输机工作的安全性和稳定性,研制了山地果园单轨运输机超声波避障系统。该系统由核心微处理器、超声波探头及收发电路、电源模块、无线通信模块和按键等组成。以规则物块、不规则小石块等作为轨道上的障碍物,以树枝、侧枝较多的盆栽柑橘树作为轨道旁的非障碍物,将超声波探头安装在3个不同位置,使运输机工作在慢、中、快3个不同的速度,测试了避障系统的工作性能。试验结果表明,在一定条件下,避障系统能识别轨道上的障碍物和轨道旁的非障碍物。该研究提升了单轨运输机在轨道上无人驾驶运行的安全性和可靠性。 相似文献
107.
108.
Considerable differences observed in the home-range size of individual three-toed woodpeckers (Picoides tridactylus) may be linked to variation in resource availability. We used radio-telemetry to test this hypothesis in an alpine mountain forest in southeastern Germany between 1994 and 2000. Stepwise backward multiple-regression showed that adaptive kernel home-range size using 95% use distribution (n=24 woodpeckers) was positively related to forest extent and tree-species diversity. Conversely, we found smaller home ranges with increasing density of potential cavity trees, and with increasing dbh-range of trees at breast height. The habitat variables shown to effect home range selection were attributes of mature boreal forests. This implied that maintaining a boreal-like habitat (i.e. spruce-dominated autochthonous forests including their natural disturbance regime) would be the best option for successful conservation of the alpine subspecies of the three-toed woodpecker. 相似文献
109.
110.
Surface area processing in GIS for different mountain regions 总被引:1,自引:0,他引:1
Surface area is a fundamental parameter derived from terrain analysis in geographical information systems (GIS) for modeling the real world. Therefore, an evaluation of the techniques implemented by GIS models is important in order to obtain reliable area measurements. The study compares two raster-based methods with a TIN-based (triangulated irregular network) method for surface area approximation using a digital elevation model (DEM) with 25 m × 25 m resolution in six mountain regions of Shandong Province, China. Raster-based method Ⅰ calculates surface-area grids from DEMs directly. Eight 3-dimensional triangles connecting the center point of each cell with the center points of the eight surrounding cells are generated and then the areas of the portions of each triangle that lay within the cell boundary are calculated and summed. Raster-based method Ⅱ produces the surface area of each cell directly from the pixel size and the slope value for the pixel. The results demonstrate that the surface areas calculated by raster-based method Ⅰ are equal to those of the TIN-based method. The results of raster-based method Ⅱ are the lowest but the difference in areas between the two raster-based methods decreases with the decrease in terrain complexity. Compared to the method with TINs, raster-based method Ⅱ can do better because it has some advantages, such as neighborhood analysis, more consistent output and faster processing speed. The results also demonstrate that the difference between surface and horizontal areas should be considered if more than 30% of the area of a region has slopes steeper than 18.2 degrees. 相似文献