首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   283篇
  免费   29篇
  2023年   3篇
  2022年   1篇
  2021年   2篇
  2020年   7篇
  2019年   14篇
  2018年   11篇
  2017年   14篇
  2016年   27篇
  2015年   14篇
  2014年   10篇
  2013年   71篇
  2012年   8篇
  2011年   9篇
  2010年   8篇
  2009年   9篇
  2008年   6篇
  2007年   8篇
  2006年   9篇
  2005年   7篇
  2004年   10篇
  2003年   6篇
  2002年   5篇
  2001年   1篇
  2000年   11篇
  1999年   6篇
  1998年   3篇
  1997年   3篇
  1996年   5篇
  1995年   3篇
  1994年   4篇
  1993年   3篇
  1991年   2篇
  1990年   1篇
  1989年   1篇
  1987年   1篇
  1985年   1篇
  1984年   2篇
  1983年   2篇
  1981年   2篇
  1980年   1篇
  1978年   1篇
排序方式: 共有312条查询结果,搜索用时 46 毫秒
21.
Harvesting different species as foods or raw materials calls for differing skills depending on the species being harvested and the circumstances under which they are being taken. In some situations and for some species, the tactics used are mainly behavioral—that is, people adjust, or adapt, their own actions to fit the behavior and circumstances of the species they are taking. Under other circumstances and for other species, the skills and tactics used may call for greater environmental preparation or manipulation. Therefore, instead of trying to distinguish people today and in the past as either foragers or farmers, it makes sense to define human subsistence behavior as an interactive matrix of species and harvesting tactics, that is, as a provisions spreadsheet.  相似文献   
22.
Ecosystem services are part of a growing trend within environment and development to analyse environmental change within the context of socially valued outcomes. Yet, ecosystem services‐based policies and analyses are increasingly criticized for failing to connect with, or even for restricting, development outcomes. This article seeks to connect environmental analysis with development outcomes better by applying the capability approach of Amartya Sen and others. It demonstrates how scientific analysis of ecosystem services sometimes conflates pathways of ecosystem management with development outcomes, but that it can be reconfigured to include more diverse values and objectives. The article argues that ecosystem services should be identified more as ‘functionings’ (in the Senian sense of valued development outcomes) rather than ‘functions’ (in the sense of biophysical, apolitical ecosystem properties) in order to indicate that ‘services’ always reflect social values, and that values and scientific explanations of underlying biophysical properties evolve together. Environmental science for socially valued outcomes such as ecosystem services is therefore an important site of political inclusion and exclusion. The article illustrates this analysis with examples of ecosystem‐based adaptation to climate change from the World Bank and government of Bangladesh, and in contrast to differing approaches from the field of sustainability science.  相似文献   
23.
24.
25.
26.
27.
28.
29.
30.
We model the relationship between coronary heart disease and smoking prevalence and deprivation at the small area level using the Poisson log-linear model with and without random effects. Extra-Poisson variability (overdispersion) is handled through the addition of spatially structured and unstructured random effects in a Bayesian framework. In addition, four different measures of smoking prevalence are assessed because the smoking data are obtained from a survey that resulted in quite large differences in the size of the sample across the census tracts. Two of the methods use Bayes adjustments of standardized smoking ratios (local and global adjustments), and one uses a nonparametric spatial averaging technique. A preferred model is identified based on the deviance information criterion. Both smoking and deprivation are found to be statistically significant risk factors, but the effect of the smoking variable is reduced once the confounding effects of deprivation are taken into account. Maps of the spatial variability in relative risk, and the importance of the underlying covariates and random effects terms, are produced. We also identify areas with excess relative risk.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号