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991.
992.
In addition to socio-economic factors, major landforms may affect the city structure and urban form. Here we show that landforms have significant effects on the city shape and street patterns of the fast-growing Iranian cities of Dezful (a river) and Khorramabad (moun- tains and valleys), but no clear effects on the cities of Yazd and Nain. Also, where the street orientation is peaked, the Gibbs/Shannon entropy (a measure of dispersion or spread) is low, but increases as the distribution becomes more uniform because of landform constraints. The streets in the old inner parts of all the cities are, on average, shorter and denser (more streets per unit area) than the streets of the newer outer parts. The entropies of the outer parts are also greater than those of the inner parts, implying that the street-length distribution gradually becomes more dispersed or spread as the city expands. All these cities have been fast growing in the past decades, with the newer outer parts expanding rapidly. As shown here, the rapidly formed outer parts (with greater dispersion in street patterns) have significantly different textures from those of the older inner parts, indicating different functionality and growth processes. These quantitative methods for street-network analysis can be used worldwide, particularly for analysing the effects of landforms on city shape and texture. 相似文献
993.
994.
<正>内蒙古自治区兴安盟国土资源局加强了矿产开发中的生态监管,具体措施有以下几点。一是依法实行矿山地质环境治理保证金制度,建立矿山地质环境治理责任机制采矿权发生转让的,由获得采矿权的新采矿权人接替承担矿山地质环 相似文献
995.
在我区经济发展中的资源制约要素中,水资源缺乏是其中之一,尤其是在我区中西部地区,水资源缺乏制约经济发展的情况尤为突出,所以开展水文工程环境地质调查工作对我区经济社会发展有着非常重要的作用。 相似文献
996.
<正>按照李世镕厅长一行赴北梁棚户区进行实地调研指导时提出的工作思路,自治区国土资源厅和包头市国土资源局开辟了"绿色通道",确保项目用地及时审批。包头市国土资源局东河分局全体干部职工,充分发扬"白加黑"、"五加二"的敬业精神,全身心地投入到北梁棚户区改造工作当中。针对北梁棚改时间紧、任务重的实际情况,组织专人对北梁棚户区项目组卷报批进展情况进行实时跟进,北梁棚改用地服务 相似文献
997.
<正>准格尔旗地处内蒙古自治区西南部,鄂尔多斯高原东端,晋陕蒙三省区交界地带,境内矿产资源富集。总面积7692平方公里,探明含煤面积2824平方公里,探明煤炭储量544亿吨,远景储量1000亿吨以上,有低灰、低磷、低硫、高发热量的"绿色煤炭"美誉。现有煤矿135座,其中井工矿78座,露天煤矿57座。近年来,准格尔旗人民政府及行业主管部门将矿区环境恢复 相似文献
998.
<正>甘肃:被征地农民养老分类参保近日,记者从甘肃省被征地农民社保政策落实情况汇报会获悉,该省对被征地农民区分不同情况解决养老问题,其中征收土地面积80%以上的被征地农民,剩余土地交回村集体后,可转为城镇户口,纳入城镇职工基本养老保险。甘肃省规定,将年满16周岁、征收土地面积占现有承包土地面积20%以上的被征地农民纳入参保范围,征收土 相似文献
999.
青翠的柏树,集结了最挺拔、最优雅的80万株,秀美而慎重地选择了辽西建昌县的一座不平常的山峰。于是,这座山也就因为生长着东北最大面积的自然柏树林而拥有了一个美丽的名字——柏山。 相似文献
1000.
Tidal marshes are an important habitat and nursery area for fish. In the past few decades, rapid economic development in the coastal areas of China has led to the interruption and destruction of an increasing number of tidal marshes. The growing interest in tidal marsh restoration has increased the need to understand the relationship between geomorphological features and fish assemblages in the design of marsh restoration projects. We studied temporal variations in, and the effects of creek geomorphological features on, the estuarine tidal creek fish community. Using modified channel nets, we sampled fish monthly from March 2007 to February 2008 from seven tidal creeks along an intertidal channel system in Chongming Dongtan National Nature Reserve. Fourteen creek geomorphological variables were measured or derived to characterize intertidal creek geomorphological features. The Gobiidae, with 10 species, was the most species- rich family. The most abundant fish species were Liza affinis, Chelon haematocheilus, and Lateolabrax maculatus. The fish community was dominated by juvenile marine transients, which comprised about 80% of the total catch. The highest abundance offish occurred in June and July, and the highest biomass occurred in December. Canonical redundancy analyses demonstrated that depth, steepness, cross-sectional area, and volume significantly affected the fish species assemblage. L. affinis favored small creeks with high elevations. Synechogobius ommaturus, Acanthogobius luridus, and Carassius auratus preferred deep, steep creeks with a large cross-sectional area and volume. These findings indicate that the geomorphological features of tidal creeks should be considered in the conservation and sustainable management of fish species and in the restoration of salt marshes. 相似文献