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兰州大学(盘旋路校区)2003年生态足迹调查分析 总被引:11,自引:2,他引:11
人均消费产品的数量是计算区域人均生态足迹关键和基础的一步。通过实地问卷调查,运用自下而上法收集资料,计算小尺度生态足迹。兰州大学(盘旋路校区)2003年的生态足迹计算结果为:人均生态足迹0.892hm^2,男、女生的人均生态足迹分别为0.976hm^2和0.788hm^2。这些数据与全国或者西部的人均生态足迹相比明显偏低,但总生态足迹为4119.3hm^2,是校园面积的73.7倍。因此,应合理利用自然资源,减少学生的生态足迹,真正做到可持续发展。 相似文献
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大学城的另类定位--广州旅游的"太阳" 总被引:1,自引:0,他引:1
从旅游的角度,运用定性分析和比较分析的方法,分析广州大学城,发现它在广州所有景区中,最有资格和条件担当广州旅游的“太阳”。它位于广州市番禺区新造镇小谷围岛,投资规模、大学数量、占地面积和规划人口容量皆为中国之最,是世界最大的人造景区,具有浓浓的文化氛围、时代气息,能够体现与闪烁广州的灵魂与精神。为此,广州应在大学城的建设中为未来角色创造更好的条件。 相似文献
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Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco. 相似文献
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在统计、收集山西师范大学各类建筑物资料的基础上,对其各类建筑物进行了震害预测和经济损失估计,给出了各类建筑物在不同烈度下的破坏结果和经济损失值,为地震灾害的综合防御提供了科学依据。 相似文献
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以中山大学人文地理学博士点为例,通过对博士生培养过程中存在的学术贡献有限、研究空洞、缺乏一手数据、重复型明显等相关问题的分析,从学术贡献的角度探讨了中国人文地理学的未来发展。 相似文献
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塔里木盆地上泥盆统及石炭系包括5个组,自下而上分别为上泥盆统东河塘组和甘木里克组,石炭系巴楚组、卡拉沙依组和小海子组。其中东河塘组和甘木里克组地质时代为晚泥盆世,巴楚组地质时代为早石炭世杜内早中期,卡拉沙依组地质时代为晚杜内中期至巴什基尔期,小海子组地层时代为巴什基尔末期至莫斯科早期。岩石类型有碎屑岩和碳酸盐岩,还有膏盐岩,并夹薄层火山碎屑岩。沉积相主要为海陆过渡相组合,包括河流、三角洲、滨岸、浅海、碳酸盐岩台地、台地边缘6种相和12种亚相及33种微相。晚泥盆世东河塘期至石炭纪发生过4次较大的海侵,海侵范围由下而上逐渐增大,至晚石炭世小海子期海侵规模最大。东河塘期开始海侵,海水由西而东侵入,此时周缘碎屑物质供应充分,主要为无障壁海岸和障壁海岸沉积,西南缘为浅海相沉积。巴楚期晚期,海侵范围进一步扩大,物源向北或北东方向退却,陆源碎屑物质注入急剧减少,形成了一套富含生屑的碳酸盐岩地层,发育了开阔台地和局限台地亚相沉积。卡拉沙依期中期海侵规模比巴楚期更大,海水深度加大,西部为开阔台地亚相沉积,其余地区为局限台地亚相沉积。卡拉沙依期晚期和小海子期海侵达最大,向东扩展,大部分地区为开阔台地亚相沉积,东部地区为局限台地亚相沉积,塔北大部分地区缺失。 相似文献
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R.M. Moore J.D. Burton P.J.LeB. Williams M.L. Young 《Geochimica et cosmochimica acta》1979,43(6):919-926
Fractionation by ultra-filtration of the dissolved organic material (DOM) in the River Beaulieu, with typical concentrations of dissolved organic carbon (DOC) of 7–8 mg C/l, showed it to be mainly in the nominal molecular weight range of 103–105, with 16–23% of the total DOC in the fraction > 105. The molecular weight distribution of DOM in the more alkaline River Test (average DOC, 2 mg C/l) was similar. In the River Beaulieu water, containing 136–314 βg Fe/l in ‘dissolved’ forms, 90% or more of this Fe was in the nominal molecular weight fraction > 105. Experiments showed that DOM of nominal molecular weight <105 could stabilize Fe(III) in ‘dissolved’ forms. The concentrations of ‘dissolved’ Fe in the river water probably reflect the presence of colloidal Fe stabilized by organic material and this process may influence the apparent molecular weight of the DOM. Dissolved. Mn (100–136 βg/l) in the River Beaulieu was mainly in true solution, probably as Mn(II), with some 30% in forms of molecular weight greater than ca 104.During mi xing in the Beaulieu Estuary, DOC and dissolved Mn behave essentially conservatively. This contrasts with the removal of a large fraction of the dissolved Fe (Holliday and LISS, 1976, Est. Coastal Mar. Sci. 4, 349–353). Concentrations of lattice-held Fe and Mn in suspended particulate material were essentially uniform in the estuary, at 3.2 and 0.012%, respectively, whereas the non-lattice held fractions decreased markedly with increase in salinity. For Mn the decrease was linear and could be most simply accounted for by the physical mixing of riverborne and marine participates, although the possibility that some desorption occurs is not excluded. The non-linear decrease in the concentration of non-lattice held Fe in particulates reflected the more complex situation in which physical mixing is accompanied by removal of material from the ‘dissolved’ fraction. 相似文献
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The journal of Global Geology (English Edition ) is sponsored by the International Cen- ter of Geoscience Research and Education in Northeast Asia, Jilin University of China. The former name of the journal was the Journal of International GeoscientiJic Research in Northeast Asia which was started in 1998 and served the scientists and teachers in geosciences in the world, particularly for the scientists from the six countries of the NE Asia including China, 相似文献