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201.
中国的环境政策、能源政策和西部大开发 总被引:6,自引:0,他引:6
概述了中国环境政策的演变与近年来的重点,分析了中国能源消费的特点与能源政策的走向,讨论了西部大开发的重要性及其两个重点。 相似文献
202.
在北京十三陵地震台建设了一个高度集成的地震观测监控系统,将原来分散的观测项目(如测震、GPS、气氡、气汞、电磁波、地电场等测项),改造为集中到一台服务器管理,在一个监控平台上统一实现了对台站数据的收集、入库、管理、处理、监控等业务;对这些观测项目可以在控制台上直接取数并将数据入库;初步实现了观测数据的收集、数据处理、数据管理、数据监控的软件管理系统,减少了系统维护工作量,方便台站工作人员操控。监控系统的地震前兆数据监管软件系统DataMonitor可准实时监视数据,检查数据的异常和到达情况,并向台站数据管理人员告警;可对数据库数据进行统计,包括数据到达情况统计、缺数统计、数据连续率统计等。该系统还提供多种前兆数据处理方法,实现对前兆数据的各种常规分析处理。 相似文献
203.
论述了修订后的《刑法》第338条规定的重大环境污染事故罪的概念、构成、特征及刑罚处罚、比较了重大环境事故罪与相关犯罪的异同,如与非法进口固体废物罪,重大责任事故罪、违反危险物品管理规定肇事罪以及因失职导致发生重大环境污染事故犯罪的区别。 相似文献
204.
Abstract: Concentrating tourism activities can be an effective way to closely manage high‐use parks and minimize the extent of the effects of visitors on plants and animals, although considerable investment in permanent tourism facilities may be required. On coral reefs, a variety of human‐related disturbances have been associated with elevated levels of coral disease, but the effects of reef‐based tourist facilities (e.g., permanent offshore visitor platforms) on coral health have not been assessed. In partnership with reef managers and the tourism industry, we tested the effectiveness of concentrating tourism activities as a strategy for managing tourism on coral reefs. We compared prevalence of brown band disease, white syndromes, black band disease, skeletal eroding band, and growth anomalies among reefs with and without permanent tourism platforms within the Great Barrier Reef Marine Park. Coral diseases were 15 times more prevalent at reefs with offshore tourism platforms than at nearby reefs without platforms. The maximum prevalence and maximum number of cases of each disease type were recorded at reefs with permanently moored tourism platforms. Diseases affected 10 coral genera from 7 families at reefs with platforms and 4 coral genera from 3 families at reefs without platforms. The greatest number of disease cases occurred within the spatially dominant acroporid corals, which exhibited 18‐fold greater disease prevalence at reefs with platforms than at reefs without platforms. Neither the percent cover of acroporids nor overall coral cover differed significantly between reefs with and without platforms, which suggests that neither factor was responsible for the elevated levels of disease. Identifying how tourism activities and platforms facilitate coral disease in marine parks will help ensure ongoing conservation of coral assemblages and tourism. 相似文献
205.
中国南极长城站室内空气微生物状况 总被引:3,自引:0,他引:3
空气微生物是空气洁净程度的重要指标、环境污染状况的真实反映[1] .十年来 ,位于南极半岛的中国长城站常年有考察队员居住和工作 ,尤其在南极之夏 ,不时有各国考察、旅游、观光者出入 .这些都给长城站空气微生物的变化带入了外来因素[2 ] .我们于 1994年 2月 ,随机对站上 19个室内测点作空气微生物考察 ,以监测和比较室内空气微生物含量状况 ,为进一步了解空气微生物的卫生学意义 ,并服务于提高南极考察队员的身体素质 ,加深对南极生态系统的理解而提供一些资料 .1 材料与方法1 .1 测点1994年 2月份分 6天对 19个室内空间作了 2 0次测定 … 相似文献
206.
Brood sex ratio is dependent on female mating status in polygynous great reed warblers 总被引:2,自引:0,他引:2
Isao Nishiumi 《Behavioral ecology and sociobiology》1998,44(1):9-14
Females capable of adjusting the sex ratio of their offspring should be more fit than females lacking such an ability. In
polygynous birds where breeding success in males is more strongly influenced by body size and/or attractiveness than in females,
females might produce more sons when predicting good conditions or when mating with attractive males. Polygynous great reed
warbler, Acrocephalusarundinaceus, males direct most of their feeding effort to the primary (first-hatching) nest and in these nests increase their feeding
effort in relation to the brood sex ratio (proportion of sons). Therefore, with the expectation of well-nourished sons, we
would predict that females which start breeding first within harems might produce more sons than those which start breeding
later, and in anticipation of sons with good genes, that females mated to polygynous males might produce more sons than females
mated to monogamous males. I took blood samples from hatchlings and determined the sex using DNA markers. The sex ratio of
primary (monogamous and polygynous primary) broods is more male-biased (mean 0.58 males, n = 50) than that of secondary (polygynous secondary and tertiary) broods (mean 0.46, n = 25). Moreover, in the secondary broods with the largest clutch (five eggs), in which offspring are most likely to suffer
food shortage, the sex ratio was distinctively female biased (mean 0.33, n = 10). In the primary broods, sex ratio was correlated to harem size. The results suggest that great reed warbler females
modify the brood sex ratio to produce both well-nourished sons and sons with good genes, but the former effect is probably
stronger than the latter factor.
Received: 11 March 1998 / Accepted after revision: 23 May 1998 相似文献
207.
The Great Lakes Hydrography Dataset: Consistent,Binational Watersheds for the Laurentian Great Lakes Basin
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Danielle K. Forsyth Catherine M. Riseng Kevin E. Wehrly Lacey A. Mason John Gaiot Tom Hollenhorst Craig M. Johnston Conrad Wyrzykowski Gust Annis Chris Castiglione Kent Todd Mike Robertson Dana M. Infante Lizhu Wang James E. McKenna Gary Whelan 《Journal of the American Water Resources Association》2016,52(5):1068-1088
Ecosystem‐based management of the Laurentian Great Lakes, which spans both the United States and Canada, is hampered by the lack of consistent binational watersheds for the entire Basin. Using comparable data sources and consistent methods, we developed spatially equivalent watershed boundaries for the binational extent of the Basin to create the Great Lakes Hydrography Dataset (GLHD). The GLHD consists of 5,589 watersheds for the entire Basin, covering a total area of approximately 547,967 km2, or about twice the 247,003 km2 surface water area of the Great Lakes. The GLHD improves upon existing watershed efforts by delineating watersheds for the entire Basin using consistent methods; enhancing the precision of watershed delineation using recently developed flow direction grids that have been hydrologically enforced and vetted by provincial and federal water resource agencies; and increasing the accuracy of watershed boundaries by enforcing embayments, delineating watersheds on islands, and delineating watersheds for all tributaries draining to connecting channels. In addition, the GLHD is packaged in a publically available geodatabase that includes synthetic stream networks, reach catchments, watershed boundaries, a broad set of attribute data for each tributary, and metadata documenting methodology. The GLHD provides a common set of watersheds and associated hydrography data for the Basin that will enhance binational efforts to protect and restore the Great Lakes. 相似文献
208.
After the Great East Japan Earthquake and Tsunami, volunteers participated in the recovery of lost photographs. This effort—which we call the Picturescue Movement—subsequently began to organise photograph restoration gatherings. We conducted field research during the gatherings in Noda, one of the tsunami-stricken areas. We have also carried out research on restoration gatherings in the city of Rikuzentakata. A comparison of findings across these two localities identifies two approaches to photograph restoration gatherings: ‘aiming’ and ‘staying'. The aiming approach, employed in Rikuzentakata, emphasises returning photographs to their owners quickly, whereas the latter approach, used in Noda, is one in which volunteers stay with survivors for some time and encourage them to recall the past at their own pace. We conclude that the staying approach is more likely than the aiming approach to promote disaster recovery among survivors. 相似文献
209.
210.
我国铁路危险货物办理站安全分析与对策 总被引:3,自引:1,他引:2
危险货物运输的源头是危险货物办理站 ,研究危险货物办理站的安全管理及存在的问题 ,具有现实意义和社会影响 ,对铁路行车安全和危货安全承运及保管至关重要。笔者通过实践和调查 ,阐述了目前我国铁路危险货物办理站安全运输中存在的主要问题 ,指出了危险货物办理站现有问题产生的原因 ,并提出了我国危险货物办理站问题解决的对策。 相似文献