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1.
With recent changes in the ways that state agencies are implementing their environmental policies, the line between public and private is becoming increasingly blurred. This includes shifts from state-led implementation of environmental policies to conservation plans that are implemented and managed by multi-sectoral networks of governments, the private sector and environmental non-governmental organizations (ENGOs). This paper examines land trusts as private conservation initiatives that become part of neoliberal governance arrangements and partnerships that challenge our conceptions of environmental preservation and democratic participation. The paper starts with an examination of the concept of neoliberalized environmental governance. Next, it addresses the shifting social constructions of property and land in the context of protecting large scale ecosystems. Through a case study of the extension of new environmental governance arrangements on the Oak Ridges Moraine in Ontario, we examine the relationships that have formed between different levels of the state and environmental non-governmental organizations. Finally, we analyze the expansion of land trusts and private conservation initiatives that are predicated on private land ownership and the commodification of nature, the emerging discourses and practices of private conservation, and how these are implicated in the privatization and neoliberalization of nature.  相似文献   
2.
东南极格罗夫山存在一套经历了峰期麻粒岩相变质作用的镁铁质麻粒岩和斜长角闪岩。对含石榴石的镁铁质麻粒岩的详细研究则显示了近等温降压 (ITD)的顺时针PT演化轨迹 ,与拉斯曼丘陵有相似的演化历史。岩石的主量元素组成和玄武岩一致 ,并且具有拉斑玄武岩演化趋势。进一步的地球化学研究表明 ,这套玄武岩为洋岛型玄武岩 (OIB)和洋中脊型玄武岩(MORB)的组合。OIB型具有大体类似的地球化学性质 ,它们均富集Ti(TiO2 =2 .68% )、REE( =2 0 2 μg/g)、LREE[(La/Yb) N=4.8]、Ti/Y( =343)、Zr/Y( =3.1 ) ,具洋岛玄武岩的特征 ,推测岩浆来源于富集地幔源区 (EM)。而MORB型以低Ti (TiO2 =1 .1 %— 1 .31 % ) ,明显低于OIB的P的含量 (P2 O5=0 .1 %— 0 .2 % ) ,低REE ( 4 7— 93μg/g)、LREE/HREE( 2 .2 7— 2 .5 4 )、(La/Yb) N( =1 .30— 1 .62 )为特征 ,具洋中脊玄武岩的特征。MORB和OIB组合的出现说明在泛非期该区可能存在过洋盆。  相似文献   
3.
格罗夫山:我国新发现的一个陨石富集区   总被引:6,自引:3,他引:6       下载免费PDF全文
刘小汉  琚宜太 《极地研究》2002,14(4):243-247
中国南极考察队在1998—2000年两次对南极洲格罗夫山地区进来了考察,共回收32块陨石,根据陨石的分布位置和岩石化学类型的差异性,初步确定格罗夫山是我国新发现的一个陨石富集区,但是该区的陨石富集模式还有待于进一步研究。  相似文献   
4.
As the core block of the East Gondwana Land, the East Antarctic Shield was traditionally thought, before 1992, as an amalgamation of a number of Archaean-Paleoproterozoic nuclei, be-ing welded by Grenville aged mobile belts during 1400—900 Ma, while the …  相似文献   
5.
东南极格罗夫山主要由麻粒岩相高级变质岩和花岗岩类组成,其中变质岩以浅色和暗色含斜方辉石长英质片麻岩占主导地位,夹有少量镁铁质麻粒岩、变沉积岩和含方柱石钙硅酸盐岩。这些岩石一般都展示了平衡的矿物共生结构,但在镁铁质麻粒岩的单斜辉石中普遍发育斜方辉石(易变辉石)的出溶片晶。根据出溶辉石的重组分析获得麻粒岩相变质作用的峰期温度约为850℃,而浅色片麻岩中的石榴子石—斜方辉石—斜长石—石英组合给出的变质压力为0.61~0.67GPa。镁铁质麻粒岩中火成亚钙质普通辉石斑晶的保存表明格罗夫山地区可能只发育单一的泛非期高温麻粒岩相变质事件,岩石在高温变质之后经历了缓慢冷却过程,这主要归因于花岗质岩浆的板底垫托作用。  相似文献   
6.
应用地面点与线路中线相对关系的统一数学模型,使用CASIO fx-4800P程序型计算器编制的适合野外测设线路各种复合曲线(包括直线、缓和曲线、圆曲线的任意组合)的实用程序。  相似文献   
7.
James M. Buttle 《水文研究》2016,30(24):4644-4653
The potential for dynamic storage to serve as a metric of basin behaviour was assessed using data from five drainage basins with headwaters on the thick sand and gravel deposits of the Oak Ridges Moraine in southern Ontario, Canada. Dynamic storage was directly correlated with the ratio of variability of δ2H in streamflow relative to that in precipitation. This ratio has previously been shown to be inversely related to basin mean transit time (MTT), suggesting an inverse relationship between dynamic storage and MTT for the study basins. Dynamic storage was also directly correlated with interannual variability in stream runoff, baseflow and baseflow:runoff ratio, implying that basins with smaller dynamic storage have less interannual variability in their streamflow regimes. These preliminary results suggest that dynamic storage may serve as a readily derived and useful metric of basin behaviour for inter‐basin comparisons. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
8.
本文分别利用光学立体和In SAR技术生成了东南极Grove山地区15 m分辨率的ASTER DEM和20 m分辨率的In SAR DEM。在利用ASTER立体像对生成DEM的过程中引入ICESat测高数据作为高程控制以减少错误匹配,提高DEM垂直精度;而在利用ERS tandem数据生成DEM后,选取ICESat测高数据对In SAR DEM进行倾斜面纠正,以消除基线不精确估计等带来的影响。通过与未作控制的ICESat测高数据进行比较,评价了两种DEM的精度并对误差进行了分析。同时,比较了两种DEM的差异,并分析了造成这些差异的原因,探讨了两种技术生成南极冰盖DEM的优势和不足。最后结合两DEM的优势,融合生成了Grove山地区高精度的DEM。  相似文献   
9.
Glaciogene sedimentary rocks have been found in modem tills of the Grove Mountains, east Antarctica during the 1998 - 1999 Chinese National Antarctic Research Expedition (CHNARE). Based on the lithilogic and sedimentary features, these sedimentary rocks are correlated with Cenozoic sedimentary strata of the Pagodroma Group in the neighboring Prince Charles Mountains and the Sorsdal Formation in VestFold Hills. Sedimentary clasts contain sparsely Late Tertiary spores and pollens, including : Toroisporis ( Lygodiaceae), Osmunda, Granulatisporites ( Pteridaceae?) , Polypodiaceae, Podocarpus , Araucariaceae, Artemisia , Rhus , Nothofagidites , Proteacidites (Proteaceae) , Quercus , Fraxinoipollenites ( Oleaceae ) , Oleoidearumpollenites( Oleaceae ), Operculumpollis, and Tricolpopollenites. Most of the pollen and spores contained in these samples originate from local sources according to the conditions of their preservations as well as correlations with the microfossil assemblages found in the neighboring areas. The majority of the pollen assemblages, as represented by Podocarpus and Nothofagus, belong to the Weddellian biogeocenose, however some exotic components from the old sedimentary basement rocks may have been included during erosion of the proximal ice sheet. If the source areas of glaciogenic sedimentary rocks that bear the pollen and spores are assumed to be local, or in the up glacier areas, the pollen assemblages in these samples might represent an inland flora during a warmer period of the ice-sheet evolutionary history. The finding of the Artemisia and Chenopodiaceae in the pollen assemblages implies that they may belong to late Tertiary (most probably Pliocene). The absence of diatoms in the samples analyzed may indicate that there are no Cenozoic marine strata in the interior of the east Antarctica beyond the Grove Mountains. The significances of the finding of the Nothofagus in these pollen assemblages are discussed on the basis of current knowledge about the age, distribution and ecological conditions of this kind of fossils found in Sirius Group or other strata outcropped in Antarctica. As a preliminary conclusion, we think that the existence of the Cenozoic glaciogenenic rocks and their pollen assemblages present new evidence for a large scale glacial retreat history in Grove Mountains of east Antarctica, and thus support a dynamic East Antarctic Ice Sheet (EAIS). This is consistent with the interpretations of Webb et al. (1984).  相似文献   
10.
基于城市公园免费开放的视角,选取南京中山陵作为研究个案,运用SPSS18.0和AMOS18.0分析软件,通过探索性和验证性因素分析,构建了游客感知价值维度分析模型。研究显示:游客对免费开放中山陵存在五维感知价值,且呈现出感知价格→休闲价值→环境价值→服务价值→文化价值逐步递减的分异特征;由此探究游客感知价值维度分异的作用机制,衍生出城市公园免费开放的效应分析,其中公益福利效应和休闲游憩效应呈现积极的正向发展态势,而生态环境效应、景区服务效应与文化内生效应的发挥则相对滞后。在倡导"以人为本"、关注民生休闲的大众旅游时代,免费开放城市公园在增强城市开放空间优质属性和综合竞争力的同时,其与城市旅游的耦合协调及可持续发展将面临新的挑战。  相似文献   
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