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313.
三峡工程与三峡库区环境保护 总被引:1,自引:0,他引:1
三峡工程是一项改善长江生态环境的工程。它一方面对库区乃至全国的经济发展有着重大的牵动作用,另一方面也将对三峡库区直至长江领域的生态环境产生广泛而深远的影响,从可持续发展思想的高度提出了实施三峡库区生态环境保护对策方略。 相似文献
314.
对沈阳市农田(水田、旱田、菜田)土壤中农药残留调查表明,禾大壮、丁草胺、敌百虫、辛硫磷、阿特拉津、乐果、氧化乐果、溴氰菊酯、1605残留量测定结果均低于检出限。六六六残留几何平均水平为0.011mg/kg.DDT为0.039mg/kg;旱田、水田六六六异构体的残留主要是β-BHC,DDT异构体的残留主要是p,p'-DDE. 相似文献
315.
316.
沈阳市冬季一次典型大气污染过程特征和成因分析 总被引:1,自引:1,他引:0
2013年11月18日~25日沈阳地区出现一次典型空气污染过程。采用单颗粒气溶胶质谱仪(SPAMS),并结合气象条件分析了该次污染的成因和细颗粒物的污染特征。结果表明,不利于污染物扩散的气象条件是重污染发生的主要原因,低空排放的积累可能是造成这次污染的又一重要原因。从细颗粒物成分上看,污染过程中有机碳颗粒占比明显增加,有机物污染较为严重,颗粒物间混合加剧;从来源上看,机动车尾气、工业排放和燃煤的占比较高。 相似文献
317.
Bradley K. Woodworth Richard A. Fuller Graham Hemson Andrew McDougall Bradley C. Congdon Matthew Low 《Conservation biology》2021,35(3):846-858
The Great Barrier Reef is an iconic ecosystem, known globally for its rich marine biodiversity that includes many thousands of tropical breeding seabirds. Despite indications of localized declines in some seabird species from as early as the mid-1990s, trends in seabird populations across the reef have never been quantified. With a long history of human impact and ongoing environmental change, seabirds are likely sentinels in this important ecosystem. Using 4 decades of monitoring data, we estimated site-specific trends for 9 seabird species from 32 islands and cays across the reef. Trends varied markedly among species and sites, but probable declines occurred at 45% of the 86 species-by-site combinations analyzed compared with increases at 14%. For 5 species, we combined site-specific trends into a multisite trend in scaled abundance, which revealed probable declines of Common Noddy (Anous stolidus), Sooty Tern (Onychoprion fuscatus), and Masked Booby (Sula dactylatra), but no long-term changes in the 2 most widely distributed species, Greater Crested Tern (Thalasseus bergii) and Brown Booby (Sula leucogaster). For Brown Booby, long-term stability largely resulted from increases at a single large colony on East Fairfax Island that offset declines at most other sites. Although growth of the Brown Booby population on East Fairfax points to the likely success of habitat restoration on the island, it also highlights a general vulnerability wherein large numbers of some species are concentrated at a small number of key sites. Identifying drivers of variation in population change across species and sites while ensuring long-term protection of key sites will be essential to securing the future of seabirds on the reef. 相似文献
318.
Assessing the effectiveness of specially protected areas for conservation of Antarctica's botanical diversity
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Vegetation is sparsely distributed over Antarctica's ice‐free ground, and distinct plant communities are present in each of the continent's 15 recently identified Antarctic Conservation Biogeographic Regions (ACBRs). With rapidly increasing human activity in Antarctica, terrestrial plant communities are at risk of damage or destruction by trampling, overland transport, and infrastructure construction and from the impacts of anthropogenically introduced species, as well as uncontrollable pressures such as fur seal (Arctocephalus gazella) activity and climate change. Under the Protocol on Environmental Protection to the Antarctic Treaty, the conservation of plant communities can be enacted and facilitated through the designation of Antarctic Specially Protected Areas (ASPAs). We examined the distribution within the 15 ACBRs of the 33 ASPAs whose explicit purpose includes protecting macroscopic terrestrial flora. We completed the first survey using normalized difference vegetation index (NDVI) satellite remote sensing to provide baseline data on the extent of vegetation cover in all ASPAs designated for plant protection in Antarctica. Large omissions in the protection of Antarctic botanical diversity were found. There was no protection of plant communities in 6 ACBRs, and in another 6, <0.4% of the ACBR area was included in an ASPA that protected vegetation. Protected vegetation cover within the 33 ASPAs totaled 16.1 km2 for the entire Antarctic continent; over half was within a single protected area. Over 96% of the protected vegetation was contained in 2 ACBRs, which together contributed only 7.8% of the continent's ice‐free ground. We conclude that Antarctic botanical diversity is clearly inadequately protected and call for systematic designation of ASPAs protecting plant communities by the Antarctic Treaty Consultative Parties, the members of the governing body of the continent. 相似文献
319.
沈阳市土壤铅对儿童血铅的影响 总被引:4,自引:1,他引:3
研究了沈阳市土壤铅和儿童血铅的动态关系,鉴于今后土壤是儿童最重要的铅暴露源,通过土壤铅预测儿童血铅,并计算当土壤铅含量削减到土壤质量二级标准时,儿童血铅恢复到安全阈值(10μg·dL-1需要的时间,从而为土壤修复提供理论依据.研究表明,土壤铅和儿童血铅的相关系数在地理区水平上最高,为0.9200,地理区客观地代表了儿童铅暴露的真实范围.西部工业区有约90%的儿童血铅水平都高于安全阈值;东部儿童血铅水平最低,几乎没有超标现象;其它地理区儿童血铅的超标范围在3.48%~31.81%.西部工业区儿童血铅恢复到安全阈值以下所需的时间最长,平均为26.68月,其次为北部、东北部、西南部、西北部和中部,东部儿童已在安全水平.无论各地理区儿童血铅水平,还是平均恢复时间和最长恢复时间都受土壤铅含量控制. 相似文献
320.
针对福田保税区的敏感地理位置 ,阐述了在该区域建设污水处理厂所采用工艺的确定过程和选择依据 ,并对第二阶段的比选工艺作了较为详细的比较 ,最终选出满足要求的SBR处理工艺 相似文献