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91.
文章从环境美学视野对城市公园景观优化设计进行研究,从环境美学的内容、应用价值、意义,以及城市公园景观优化设计中应用环境美学的原则入手,以泉州市西湖公园为例,介绍其景观优化设计方式,包括改善西湖公园湖滨游步道的林荫绿化情况,增建亲水空间,优化座椅、休闲亭和餐饮设施,改善水景别墅前绿化景观,提升公园整体植物景观层次感,规划西湖水生植物景观。从而总结出滨水公园景观优化设计的策略主要为:设计湖滨亲水设施、营造水上景观、配置滨水植物景观、设置沿岸小型水景。  相似文献   
92.
郑怀兵  张民侠  汶林科 《安徽农业科学》2013,(22):9313-9315,9500
利用中国气象局公布的日降水资料建立湘西地区5~9月2、3、5d最大降水的3种极端降水指数,发现ENSO对其后雨季湘西地区的极端降水有显著影响,其中前年7月至当年2月的相关系数都达到0.4以上,通过了0.01水平的显著性检验.而1910 ~ 1981年洪水的统计显示,极端降水与湘西暴发洪水河流的条数有着很好的相关关系,而且在时间上也有较好的对应,表明极端降水是造成湘西洪水的主要原因.进一步分析发现,Nino3区海温与极端降水及洪涝之间都存在显著正相关关系,表明在El Nino年湘西地区暴发洪水灾害的可能性更大.  相似文献   
93.
采用铗日法对贺兰山西坡鼠类的内脏重量与海拔梯度关系情况进行了细致研究。选取8条典型沟道为样线,共布设有效铗日18 748个,捕获鼠类235只。阿拉善黄鼠和大林姬鼠在所有海拔梯度均有分布,其次是社鼠、灰仓鼠和短尾仓鼠,海拔分布范围最小的是高山鼠兔和东方田鼠。阿拉善黄鼠的肺脏和肾脏重量高海拔重量远高于低海拔重量,显示出了其对外界环境的超强适应能力。  相似文献   
94.
基于GIS的济南市土壤侵蚀敏感性评价研究   总被引:3,自引:0,他引:3  
土壤侵蚀受多种因素的影响和制约.根据美国土壤侵蚀通用方程以及济南市独特的自然地理特征,确定了济南市土壤侵蚀敏感性主要评价因子,包括降水、地形起伏、土壤质地和植被.在GIS系统支持下,提取单因子数据并得到单因子土壤侵蚀敏感性,进而完成土壤侵蚀敏感性综合评价.运用GIS空间分析功能,得到不同敏感性程度的面积与空间分布规律,从而为政府制定水土保持政策提供科学依据.  相似文献   
95.
LIU Pengde 《干旱区科学》2021,13(11):1163-1182
West Junggar is a key area for understanding intra-oceanic plate subduction and the final closure of the Junggar Ocean. Knowledge of the Carboniferous tectonic evolution of the Junggar Ocean region is required for understanding the tectonic framework and accretionary processes in West Junggar, Central Asian Orogenic Belt. A series of Early Carboniferous volcanic and intrusive rocks, namely, basaltic andesite, andesite, dacite, and diorite, occur in the Mayile area of southern West Junggar, northwestern China. Our new LA-ICPMS zircon U-Pb geochronological data reveal that diorite intruded at 334 (±1) Ma, and that basaltic andesite was erupted at 334 (±4) Ma. These intrusive and volcanic rocks are calc-alkaline, display moderate MgO (1.62%-4.18%) contents and Mg# values (40-59), and low Cr (14.5×10-6-47.2×10-6) and Ni (7.5×10-6-34.6×10-6) contents, and are characterized by enrichment in light rare-earth elements and large-ion lithophile elements and depletion in heavy rare-earth elements and high-field-strength elements, meaning that they belong to typical subduction-zone island-arc magma. The samples show low initial 87Sr/86Sr ratios (range of 0.703649-0.705008), positive εNd(t) values (range of 4.8-6.2 and mean of 5.4), and young TDM Nd model ages ranging from 1016 to 616 Ma, indicating a magmatic origin from depleted mantle involving partial melting of 10%-25% garnet and spinel lherzolite. Combining our results with those of previous studies, we suggest that these rocks were formed as a result of northwestward subduction of the Junggar oceanic plate, which caused partial melting of sub-arc mantle. We conclude that intra-oceanic arc magmatism was extensive in West Junggar during the Early Carboniferous.  相似文献   
96.
魏晋南北朝时期中原的战乱促使河北山东等地的世家大族及流民纷纷迁徙到辽西地区,此地的人口数量大为增加,且带来了中原地区的先进生产技术。十六国时期,先后统治辽西地区的前燕、后燕、北燕三个地方政权对农业的重视和发展,加之优越的生态环境和悠久的农耕基础,辽西农业在耕作技术、作物的种类、水利灌溉等方面都有了较快发展,且带动了慕容鲜卑由畜牧经济向农耕经济的转变。农业生产虽受自然灾害和战争等因素的限制但整体上呈现波浪式发展。  相似文献   
97.
West Nile virus lineage 2 (WNV‐2) was detected in the brain of 17 goshawks (Accipiter gentilis) that succumbed to neuroinvasive disease in the Czech Republic during 2018: twelve birds were captive and five wild. Furthermore, two wild sparrowhawks (Accipiter nisus) and three other captive birds of prey (golden eagle Aquila chrysaetos, hybrid saker falcon Falco cherrug × F. rusticolus and Harris's hawk Parabuteo unicinctus) also died due to WNV encephalitis. The 2018 outbreak in Czech raptors clearly reflects a new epidemiological situation and indicates an increasing risk of both raptor and human infection with WNV‐2 in the country.  相似文献   
98.
In the recent years, USUTU virus (USUV), a flavivirus of the Japanese encephalitis virus complex, has been reported in Central Europe. As part of a systematic surveillance programme to monitor possible entrance and/or circulation of vector-borne viruses, since 2001, sentinel-chicken flocks were placed throughout the Italian territory nearby areas considered at risk of virus introduction. They have been periodically checked for the presence of antibodies against flaviviruses by indirect ELISA, plaque reduction neutralization test for USUTU, West Nile and tick-borne encephalitis viruses. In July 2007, a sentinel chicken in a flock of 20 animals located within the Ravenna province seroconverted to USUV reaching neutralizing titres up to 1:5120. A second chicken seroconverted to the same virus 2 months later. Although no virus was rescued from these animals and from wild or farm birds sampled in the area, these results still provided evidence of the circulation of USUV in north-eastern Italy.  相似文献   
99.
Customary land-use practices create distinctive cultural landscapes, including landscapes where abandoned settlements host vegetation that attracts wild animals. Understanding how landscape patterns relate to land-use history can help clarify the ecological effects of particular land uses. This study examines relationships between chimpanzee habitat selection and Maninka settlement practice, to determine how settlement history has affected chimpanzee habitat in Mali’s Bafing Biosphere Reserve, where conservation practitioners assume that the characteristic settlement pattern reflects a process of settlement expansion into undisturbed habitat. Three types of data are reported: (1) ethnographic interviews on settlement history and practice; (2) systematic sampling of chimpanzee habitat use; and (3) ground-based mapping of settlement sites, surface water, and fruit-tree patches. These data show that the Maninka have a shifting settlement system, meaning that most sites are occupied for only relatively brief periods; and that some abandoned settlement sites host fruit-tree patches that are seasonally important chimpanzee habitat. Two main conclusions are: (1) settlement expansion has not occurred; instead, historic settlement has created habitat that is both attractive and available to chimpanzees. Anthropogenic habitat does not appear to be vital for chimpanzee survival, but it spatially and temporally supplements natural habitats. (2) Conservation policies meant to reduce the presumed threat of settlement expansion may have initiated an unintended, long-term threat of habitat loss for chimpanzees. While settlement practices may be a component of short-term threats to chimpanzees, such as hunting, when addressing these threats conservation practitioners should consider long-term settlement processes to avoid creating new threats.  相似文献   
100.
通过对西湖风景区内水生植物园林应用情况的大量调查,得到应用种类、分布与应用频率及相应种类的生长发育规律等与水生植物园林应用密切相关的几个要素,并据此对其作了较为全面的分析,将为以后更加科学合理的应用提供良好依据.  相似文献   
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