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211.
Social capital's role in recovery: evidence from communities affected by the 2010 Pakistan floods
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Pakistan suffered large‐scale flooding in summer 2010 that caused damage amounting to approximately USD 43 billion, claimed the lives of at least 1,700 people, and negatively affected some 20 million others. Observers have debated the degree to which social capital plays a role in recovery after a catastrophe of this magnitude. Using new survey data on 450 residents impacted by the disaster, this study found that, controlling for various confounding factors, the social capital levels of victims serve as robust correlates of life recovery. Other important variables connected with recovery include education and income, family size, occupation, material damage suffered, stability of home, and trauma experience. The findings point to a number of relevant policy recommendations, most notably that during and following major shocks, disaster managers should work to keep the social networks of victims intact so that they can benefit from interaction with family, friends, and neighbours. 相似文献
212.
通过野外调查取样,应用Menhinick丰富度指数、Simpson指数、Shannon-Wiener指数和Pielou均匀度指数研究了冀北山区12种典型森林群落内的草本植物多样性规律,并采用典范对应分析(CCA)方法研究其分布与地形的关系。结果表明:不同的群落类型草本植物的组成和多样性指数不同,山杨(Populus davidiana)纯林的种数最多为34种,黑桦(Betula dahurica Pall)纯林的种数最少为19种,其Simpson指数、Shannon-Wiener指数最高,分别为0.927 3和2.879 6;在1 200~1 700 m之间,随海拔升高物种多样性指数、均匀度指数和丰富度指数呈正相关性,但没有线性上升的趋势关系;选取的地形因子对样点草本的影响程度大小为:坡向〉海拔〉坡度〉坡位〉坡形,坡向是样点草本植物空间差异的最主要地形制约因子,环境解释率为98.7%,证明排序可信。 相似文献
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V. V. Tarasov 《Russian Journal of Ecology》2005,36(3):193-199
The return of willow ptarmigans to the sites in which they nested the previous year has been studied using color banding. No factors influencing the return index have been revealed, except for its dependence in males on the time when spring begins in a given year. In northernYamal, in contrast to the temperate zone, some surviving birds fail to return to their former nesting sites. Polymorphism of individuals with respect to territorial behavioral strategy is proposed for L. lagopus populations at the northern boundary of the species range.__________Translated from Ekologiya, No. 3, 2005, pp. 215–221.Original Russian Text Copyright © 2005 by Tarasov. 相似文献
214.
Bentonite clay has been used for the adsorption of Fe(II) from aqueous solutions over a concentration range of 80-200 mg/l, shaking time of 1-60 min, adsorbent dosage from 0.02 to 2 g and pH of 3. The process of uptake follows both the Langmuir and Freundlich isotherm models and also the first-order kinetics. The maximum removal (>98%) was observed at pH of 3 with initial concentration of 100 mg/l and 0.5 g of bentonite. The efficiency of Fe(II) removal was also tested using wastewater from a galvanized pipe manufacturing industry. More than 90% of Fe(II) can be effectively removed from the wastewater by using 2.0 g of the bentonite. The effect of cations (i.e. zinc, manganese, lead, cadmium, nickel, cobalt, chromium and copper) on the removal of Fe(II) was studied in the concentration range of 10-500 mg/l. All the added cations reduced the adsorption of Fe(II) at high concentrations except Zn. Column studies have also been carried out using a certain concentration of wastewater. More than 99% recovery has been achieved by using 5 g of the bentonite with 3M nitric acid solution. 相似文献
215.
江西省大湖塘石门寺矿区超大型钨矿的发现及找矿意义 总被引:10,自引:0,他引:10
江西省武宁县大湖塘石门寺超大型钨矿的成功勘查是我国地质找矿工作的重大发现。矿化类型划分为细脉浸染型、隐爆角砾岩型和石英大脉型。前者占总储量的74%,该类型以晋宁晚期黑云母花岗闪长岩为容矿围岩,以燕山中期酸性深成至浅成花岗岩为成矿母岩。矿体厚大且产状平缓,大致平行于黑云母花岗闪长岩与似斑状黑云母花岗岩株顶部的接触面分布,以外接触带为主(Ⅰ1矿体),水平投影面积1.50km2,单工程最大厚度389.33m,平均厚度143.67m,平均品位0.193%,厚度变化系数63.7%,品位变化系数115.8%。工业矿物主要为白钨矿、黑钨矿、黄铜矿、辉钼矿。矿石组构类型主要有结晶结构、交代结构、细脉状构造、浸染状构造,常见近矿围岩蚀变为黑鳞云母化、云英岩化、绿泥石化,成因类型属岩浆期后高中温热液矿床,工业类型可划归为细脉浸染型白钨矿。石门寺矿区以黑云母花岗闪长岩为容矿围岩的细脉浸染状白钨的发现,改变了以往只专注评价石英大脉型黑钨矿的找矿思路,为矿区及九岭矿集区实现钨多金属找矿突破指明了新的方向。 相似文献
216.
北武夷梨子坑火山盆地流纹斑岩与铅锌矿的成因关系 总被引:2,自引:0,他引:2
梨子坑火山盆地位于北武夷中生代月凤山—梨子坑火山岩带东段,已知铅锌(铜、银)矿体或矿化呈细脉-浸染型、脉状,产于流纹斑岩脉的内外接触带及其外侧围岩中,发育钾化、绿泥石化、硅化、绿帘石化等围岩蚀变。地球化学特征显示流纹斑岩为钙碱性系列,岩石具有高SiO2、富碱、高K2O、高钙铁、低镁、K2O/Na2O值偏高的特点,为强过铝质岩石。w(ΣREE)值为76.28×10-6~222.54×10-6,ω(ΣLREE/ΣHREE)比值较大,为4.08~12.30,属于轻稀土元素富集型。成矿流纹斑岩形成于137±2.1Ma(SHRIMP锆石U-Pb法)~138.8±1.4Ma(LA-MC-ICPMS锆石U-Pb法),属早白垩世。铅锌矿属于次火山斑岩脉型铅锌(银铜)成矿系列,划分为次火山斑岩脉型和次火山热液破碎带型两种矿床成因类型。 相似文献
217.
生计风险作为移民社会整合的标尺,已成为研究生态移民生计及可持续发展的重要视角。以祁连山北麓的武威市为例,利用Binary Logistic模型分析了移民生计风险对其应对策略的影响机制,以期为制定有效的生计风险防范体系提供科学支撑。结果表明:(1)武威市生态移民的生计类型以非农户为主,纯农户比例不足10%,生计多样化指数仅为1.74且存在显著的区域差异。(2)67.44%的移民面临着多重风险,以经济风险为主,生活开支大、新分棚圈耕地质量差、返贫是主要的风险要素。(3)应对策略主要为向亲朋借钱、银行贷款、外出打工和减少开支,后顾生计则多选择扩大养殖、长期打工和维持现状,不同县区移民的策略选择略有不同。(4)政策、福利和经济风险会显著影响移民对“向银行贷款”“减少开支”及“外出打工”等应对策略的选择,而后顾生计的选择更多受制于生计资本储量,而政策及经济风险的影响较低。移民户的类型对策略选择影响显著,非农型兼业户更倾向于选择“向银行贷款”和“扩大养殖”。 相似文献
218.
While a strong relationship has been established between social capital and food security in the research literature, it is uncertain whether this holds in post-conflict situations. This study examines associations between social capital and food security in post-conflict Lira District, northern Uganda. Since factors affecting food security are complex, we explored the roles of households' characteristics in food security outcomes. Data were collected from March to July 2011 through face-to-face interviews with 221 heads of household in rural Lira. Using multinomial logistic regression, a strong positive association was identified between social capital and household food security. The study also found significant associations of food security with sex, education of household head, amount of cultivated land, and farm and home possessions. The results of this analysis can aid the design of food security programmes that empower poor people while targeting the most vulnerable groups, thereby promoting sustainable development in post-conflict communities. 相似文献
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