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151.
天宝山多金属矿床地球化学模式   总被引:2,自引:0,他引:2  
天宝山铅锌矿山正处于资源枯竭状态,在该矿山附近寻找新的矿床对天宝山矿山来说是当务之急。我们对现有的区域地球化学和地质资料进行分析研究,总结出天宝山多金属矿床的水持地球化学异常特征、地球化学异常分带模式及地球化学找矿模式,在此基础上,提出了光新屯找远景区。  相似文献   
152.
莫莫格湖泊群近50年来的环境变化   总被引:20,自引:3,他引:17  
莫莫格源泊群水痊和生态环境的变化,主要取决于大气降水和河流水位的变化,近50年来,湖区气温逐渐上升,在自然因素和人为活动的影响下,源泊水位有逐渐下降的趋势,源泊生态环境不断恶化。  相似文献   
153.
土体工程地质层组的划分   总被引:3,自引:1,他引:2  
工程地质岩组的划分是岩体质量评价的基础。当大型工程揭露土层很多时,进行土体工程地质层组的划分亦是十分必要的。它可以更为清晰的反映场地地质结构的变化规律,便于地质模型的概化和参数研究,有助于抓住主要工程地质问题进行评价,便于设计师的理解和应用。以南京地铁南北线一期工程为例,探讨了土体工程地质岩组的划分问题。通过以层组为基础的参数离散性统计、工程地质模型与工程地质问题的分析可以看出该层组划分方案的合理性与工程意义。  相似文献   
154.
海南岛近岸海域夏初浮游动物与环境因子的关系   总被引:4,自引:1,他引:3  
根据2011年夏初在海南岛近岸海域采集的浮游动物样本,分析了该海域浮游动物的种类组成、优势种类、丰度、生态类群,生物多样性及均匀度,并对浮游动物与环境因子之间的关系进行了探讨。海南岛近岸海域共鉴定出终生性浮游动物164种,阶段性浮游幼体11个类群,其中以桡足类的种类最多,40属82种。优势种主要有棘皮动物幼体Echinodermata larva、鸟喙尖头溞Penilia avirostris、异体住囊虫Oikopleura dioica、长尾类幼体Macrura larva、肥胖软箭虫Ferosagitta enflata、羽长腹剑水蚤Oithona plumifera、小齿海樽Doliolum denticulatum、中型莹虾Lucifer intermedius、泡抱球虫Globigerina bulloides、微驼隆哲水蚤Acrocalanus gracilis等。海南岛近岸海域浮游动物丰度平均值为1 348.68ind/m3,东部海域浮游动物丰度最高,由近岸向远岸呈递减趋势,而北部湾海域和南部海域由近岸向远岸则呈先增后减的趋势。夏初由于受沿岸流和南海暖流的影响,海南岛近岸海域的生态类群以暖水沿岸种和广布暖水外海种为主。浮游动物多样性指数和均匀度平均值为3.03和0.72,东部海域的多样性指数和均匀度较低,主要原因是阶段性浮游幼体的偶然性暴发。相关性分析显示,海南岛近岸海域浮游动物丰度与pH值呈极显著负相关(p0.05,r=-0.360);与浮游植物丰度(PA)呈极显著正相关(p0.01,r=0.395);与盐度、DO、CODMn、NO3-N浓度、NH4-N浓度、PO4-P浓度成正相关,与温度、NO2-N浓度、SiO3-Si浓度呈负相关。  相似文献   
155.
Grass seed farmers have burned their fields in Idaho and Washington State for decades. Field burning, however, creates small particulate matter air pollution, thus engendering a growing public backlash by the 1990s that manifested itself in new clean air advocacy groups. The new groups’ push for policy change eventually met with significant success in both cases. How did each set of advocates approach the challenge of policy change? More specifically, what kinds of policy venues did each group choose and why? This research uses the cases to explore and explain each clean air group's choices vis-à-vis hypotheses of venue choice. Three hypotheses are tested—Schattschneider's (1960 Schattschneider , E. E. 1960 . The semisovereign people . New York , NY : Holt, Rinehart, and Winston . [Google Scholar]) “expanded scope of conflict” thesis, ACF's (Sabatier and Jenkins-Smith 1999 Sabatier , P. , and H. Jenkins-Smith . 1999 . The advocacy coalition framework: An assessment . In Theories of the policy process , ed. P. A. Sabatier , 117166 . Boulder , CO : Westview Press . [Google Scholar]) contention that groups strategically apply their resources in order to increase the likelihood of achieving their primary goal(s), and Pralle's (2003 Pralle , S. B. 2003 . Venue shopping, political strategy, and policy change . J. Public Policy 23 : 233260 .[Crossref] [Google Scholar], 2010 Pralle , S. B. 2010 . Shopping around: Environmental organizations and the search for policy venues . In Advocacy organizations and collective action , ed. A. Prakash and M. K. Gugerty , 177203 . Cambridge , MA : Cambridge University Press .[Crossref] [Google Scholar]) thesis that internal group constraints deter groups from moving into new venues.  相似文献   
156.
Compact groups are association of 4-8 galaxies with high spatial densities (Δρ/ρ∼10–20), but low velocity dispersion. Galaxy-galaxy interactions (e.g. close tidal encounters or mergers) are therefore likely to dominate any environmentally-dependent evolution of galaxies in these compact, highlocal-density, groups, unlike in the field, where galaxy densities are too low, and in clusters, where relative velocities are too high. We present here the results from spectroscopic and photometric observations of a new sample of compact groups in the Southern Sky, selected by an automatic detection algorithm applied to a digitized galaxy database. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
157.
We summarize the results of our survey of rotation curves for edge-on galaxies. The observations were carried out with the 6-m Special Astrophysical Observatory telescope. Over the four years of our observations, we obtained spectra for 306 galaxies from the FGC catalog (Karachentsev et al. 1993). Rotation curves and radial velocities are given for 135 galaxies. The median radial velocity of the galaxies studied is 7800 km s?1. Together with the observations performed by other authors with different instruments, this survey allowed us to produce a homogeneous sample of edge-on galaxies from the RFGC catalog (Karachentsev et al. 1999) uniformly distributed over the entire sky and to analyze the velocity field of galaxies on scales up to 100 Mpc.  相似文献   
158.
The largest concentration of isolated indigenous peoples in the world is in the indigenous lands of the Brazilian Legal Amazon. However, the right to self-isolation and the survival of these societies are at risk because powerful interests want to exploit the natural assets of their relatively untouched areas. These ambitions are reflected in a recent bill (PL191/2020), which proposes opening up indigenous lands to mining. We assess the threat imposed by mining to isolated peoples and the indigenous territories they occupy. Specifically, we cross data on mining requests received by the National Mining Agency with information on the distribution of isolated indigenous groups recorded by the Socio-Environmental Institute, in order to evaluate the number and aerial extent of requests for mineral prospecting and operation registered in indigenous lands with isolated groups. We also analyze whether mining requests are related to the presence of isolated groups, the state of knowledge about them, and the current existence of illegal mining operations. Our results indicate that, even though mining is not yet allowed in indigenous lands, mining companies are very active in the search for exploitable areas in these territories. If bill PL191/2020 passes, mining operations would affect more than 10 million hectares in 25 indigenous lands in the Legal Amazon region that are home to 43 isolated groups. We found that the situation is especially worrisome for 21 isolated groups whose lands concentrate 97% of all mining requests. Mineral-rich areas overlap remote areas where more indigenous peoples persist in isolation, so that mining requests are significantly related to the presence of isolated groups. Nonetheless, we show that companies are hesitant to invest in lands with well-known isolated groups that could impede the licensing process and pose reputational risks to the companies. Brazil’s mechanisms for environmental and indigenous protection have been dismantled by the current presidential administration and offer no guarantees for a safe coexistence between extractive operations and isolated peoples. Thus, the approval of bill PL191/2020 could lead to undesired contact and the extinction of a large number of unique peoples, societies and cultures.  相似文献   
159.
文章基于ASTER和Landsat-8OLI两种多光谱遥感数据,采用高光谱遥感技术混合调谐滤波(MTMF)、多光谱遥感技术相对吸收深度(RBD)、波段比值(BR)等方法提取了西藏多龙矿集区地堡那木岗斑岩型铜金矿床地表的蚀变矿物组合。其结果表明,基于ASTER数据的MTMF技术可将Al—OH矿物划分为白云母+高岭石/蒙脱石和地开石+蒙脱石+累托石两种组合,进一步可细分出斑岩型矿床多光谱遥感地表蚀变矿物组合并呈现出良好的分带特征:地堡那木岗铜金矿床自内而外依次为白云母+高岭石/蒙脱石→地开石+蒙脱石+累托石→Mg—OH类矿物组合,分别对应于前人野外调查所勘测到的的绢英岩化带+泥化带→泥化带→青磐岩化带,Fe3+矿物叠加于绢英岩化带、泥化带及其两带的叠合部位。所提取的多光谱遥感蚀变矿物组合分带特征对该区斑岩型铜金矿床的勘查工作提供了重要的遥感线索,对定位找矿靶区具有指导意义。  相似文献   
160.
Does civil society lobbying affect states’ policies on climate change? Does it facilitate or hamper cooperation towards ‘greener’ policies? Environmental non-governmental organizations (ENGOs) and business lobbying groups alike are increasingly seeking to access states’ negotiation delegations at the United Nations Framework Convention on Climate Change (UNFCCC) in order to affect or even change official delegates’ policies. Previous studies have failed to control for the fact that the set of states that have granted civil society access to their delegations is unlikely to be a random sample. Moreover, the fact that a delegation's policy outputs may converge with the preferences of a civil society group cannot be taken as evidence that it was caused by civil society lobbying. A matching approach that addresses both problems is proposed, which corrects for the non-random assignment of civil society organizations to state delegations and forms quasi-experimental contrasts by sampling a set of ‘most similar’ cases that only differ in their treatment; i.e. civil society lobbying. This approach facilitates a causal interpretation of lobbying efforts. The results indicate that only business groups are likely to exert a causal influence on states’ climate delegations. However, contrary to expectations, these groups appear to have enhanced states’ efforts towards environmentally friendly policies.

Policy relevance

What impact can non-governmental actors have in influencing states’ policies at the climate change negotiations? This question is addressed empirically using a matching approach, which corrects potential challenges in the research on interest group influence. It is shown that business groups are likely to influence states’ policies at the UNFCCC – unlike green interest groups or civil society in general. In light of these findings, three policy implications are derived that might be of importance for states and non-governmental decision makers alike. Most importantly, ENGOs should refocus their efforts for exerting their influence. ENGOs could make their lobbying more effective by first identifying the states that may be more receptive to their preferences and positions.  相似文献   
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