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   6篇
  免费   2篇
环保管理   1篇
综合类   1篇
基础理论   4篇
污染及防治   2篇
  2021年   1篇
  2017年   2篇
  2013年   1篇
  2012年   1篇
  2010年   1篇
  2008年   1篇
  1999年   1篇
排序方式: 共有8条查询结果,搜索用时 33 毫秒
1
1.
Why social values cannot be changed for the sake of conservation   总被引:1,自引:0,他引:1       下载免费PDF全文
The hope for creating widespread change in social values has endured among conservation professionals since early calls by Aldo Leopold for a “land ethic.” However, there has been little serious attention in conservation to the fields of investigation that address values, how they are formed, and how they change. We introduce a social–ecological systems conceptual approach in which values are seen not only as motivational goals people hold but also as ideas that are deeply embedded in society's material culture, collective behaviors, traditions, and institutions. Values define and bind groups, organizations, and societies; serve an adaptive role; and are typically stable across generations. When abrupt value changes occur, they are in response to substantial alterations in the social–ecological context. Such changes build on prior value structures and do not result in complete replacement. Given this understanding of values, we conclude that deliberate efforts to orchestrate value shifts for conservation are unlikely to be effective. Instead, there is an urgent need for research on values with a multilevel and dynamic view that can inform innovative conservation strategies for working within existing value structures. New directions facilitated by a systems approach will enhance understanding of the role values play in shaping conservation challenges and improve management of the human component of conservation.  相似文献   
2.
Oishi K  Toyao K  Kawano Y 《Chemosphere》2008,73(11):1788-1792
The suppressive effects of cyclodextrins (CDs) on the strong estrogenic activity of 17β-estradiol (E2) in water environments were investigated in this study. Cyclodextrins are doughnut-shaped molecules that possess a hydrophobic cavity and a hydrophilic exterior. The cavity can incorporate nonpolar molecules as guests to form inclusion complexes. β-CD and 2-hydroxypropyl-β-CD (HP-β-CD) were the most successful in forming a complex with E2 and improving its low aqueous solubility. The E2/CDs complexes bound to the estrogen receptor in a cell-free system as determined by ELISA and suppressed the hormone activities as measured by a yeast two-hybrid assay. These results indicate that hydrophobic E2 is easily transported through the lipid zone of the plasma membrane into the target cell and can bind to the nuclear receptor. However, the hydrophilic E2/β-CD and E2/HP-β-CD complexes do not penetrate the membrane. Therefore, these CDs are able to suppress the hormone activity of E2 through complex formation.  相似文献   
3.
Food and Environmental Virology - This study investigated the influence of viral interference on the detection of enteric viruses using the integrated cell culture (ICC)-PCR with a BGM cell line....  相似文献   
4.
K. Oishi  M. Saigusa 《Marine Biology》1999,133(2):237-247
Temporal fluctuations of abundance (or emergence) in small benthic and planktonic crustaceans were studied in shallow subtidal waters (1.5 to 3.5 m in tide height). The abundances were more or less rhythmic, and showed wide diversity ranging from very clear nocturnal patterns to patterns in sychrony with the tidal cycle alone. These abundance patterns were classified into categories relating to the degree of synchrony with day/night and tidal cycles. Nocturnal patterns were especially strong in benthic crustaceans, which would be inactive during the daytime, being attached to algae and stones or disappearing into rock crevices, and actively swim in the water at night. Mysis larvae also showed a clear nocturnal pattern. Their lifestyle might be similar to that of many benthic animals. Other planktonic crustaceans drifting in the water showed weak nocturnal patterns. In some planktonic crustaceans (e.g., Calanoida), the ratio of abundance in the surface and bottom samples was reversed between day and night. Their pattern might be a manifestation of weak diel vertical movement between day and night. Furthermore, most patterns of zooplankton and benthos were modified in synchrony with tides to various degrees. Small crustaceans may respond to changes of hydrologic variables fluctuating with the tides, which may exogenously produce a weak tidal component in their emergence patterns. Received: 12 January 1998 / Accepted: 29 August 1998  相似文献   
5.
6.
Trail settings in national parks are essential management tools for improving both ecological conservation efforts and the quality of visitor experiences. This study proposes a plan for the appropriate maintenance of trails in Chubusangaku National Park, Japan, based on the recreation opportunity spectrum (ROS) approach. First, we distributed 452 questionnaires to determine park visitors’ preferences for setting a trail (response rate = 68 %). Respondents’ preferences were then evaluated according to the following seven parameters: access, remoteness, naturalness, facilities and site management, social encounters, visitor impact, and visitor management. Using nonmetric multidimensional scaling and cluster analysis, the visitors were classified into seven groups. Last, we classified the actual trails according to the visitor questionnaire criteria to examine the discrepancy between visitors’ preferences and actual trail settings. The actual trail classification indicated that while most developed trails were located in accessible places, primitive trails were located in remote areas. However, interestingly, two visitor groups seemed to prefer a well-conserved natural environment and, simultaneously, easily accessible trails. This finding does not correspond to a premise of the ROS approach, which supposes that primitive trails should be located in remote areas without ready access. Based on this study’s results, we propose that creating trails, which afford visitors the opportunity to experience a well-conserved natural environment in accessible areas is a useful means to provide visitors with diverse recreation opportunities. The process of data collection and analysis in this study can be one approach to produce ROS maps for providing visitors with recreational opportunities of greater diversity and higher quality.  相似文献   
7.
We found a significant geographic gradient (longitudinal and latitudinal) in the sulfate (SO42?) concentrations measured at multiple sites over the East Asian Pacific Rim region. Furthermore, the observed gradient was well reproduced by a regional chemical transport model. The observed and modeled SO42? concentrations were higher at the sites closer to the Asian continent. The concentrations of SO42? from China as calculated by the model also showed the fundamental features of the longitudinal/latitudinal gradient. The proportional contribution of Chinese SO42? to the total in Japan throughout the year was above 50–70% in the control case, using data for Chinese sulfur dioxide (SO2) emission from the Regional Emission Inventory in Asia (40–60% in the low Chinese emissions case, using Chinese SO2 emissions data from the State Environmental Protection Administration of China), with a winter maximum of approximately 65–80%, although the actual concentrations of SO42? from China were highest in summer. The multiple-site measurements and the model analysis strongly suggest that the SO42? concentrations in Japan were influenced by the outflow from the Asian continent, and this influence was greatest in the areas closer to the Asian continent. In contrast, we found no longitudinal/latitudinal gradient in SO2 concentrations; instead SO2 concentrations were significantly correlated with local SO2 emissions. Our results show that large amounts of particulate sulfate are transported over long distances from the East Asian Pacific Rim region, and consequently the SO42? concentrations in Japan are controlled by the transboundary outflow from the Asian continent.  相似文献   
8.
1
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