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601.
环境与生态系统资本价值评估的若干问题 总被引:17,自引:0,他引:17
近年来,环境与生态系统资本价值评估中的概念界定、系统价值认定及评价模式选择等之类的问题成为相关研究中有争议的议题.鉴于此,对环境与生态系统资本价值评估中的一些问题进行了探讨.①在肯定环境与生态系统资本价值评估意义的基础上,指出对于环境与生态系统的整体价值要予以充分估价;②针对目前评价模式单一的现状,提出了整合类型与区域评估的新模式;③在分析了环境与生态系统的资本价值在空间上流动之后,认为应对价值的积累和流动过程给予充分关注;最后,提出了几条具体的建议. 相似文献
602.
针对高锰酸盐指数(CODMn)和氨氮(NH3-N)标准溶液(以下简称液标)制造商、浓度水平和使用情况进行调研,根据调研结果选择常用的7个品牌CODMn液标和9个常用NH3-N液标品牌开展量值比对和质量评价研究,匿名采购129支液标经盲样编码后采用《地表水环境质量标准》(GB 3838—2002)推荐标准进行分析测定,计算和评定测定结果的不确定度,以En法进行量值比对评价。研究表明,NH3-N液标量值均满意,CODMn测试中的加盖操作会使测定结果偏高,按照证书要求操作时CODMn液标量值合格,未按照液标证书中要求进行液标样品前处理测定会造成测定结果的偏离,影响评价结果。建议监测人员合理选用和规范使用环境用液标,加强环境用液标的选购和管理,确保检测过程得到有效控制。 相似文献
603.
Sydney T. Bacchus 《Journal of the American Water Resources Association》2000,36(3):457-481
ABSTRACT: Unsustainable withdrawals from regional aquifers have resulted in adverse impacts considerable distances from the point locations of supply wells. In one area of the southeastern (SE) Coastal Plain, conservative estimates for repair/replacement of some residential wells damaged or destroyed by unsustainable yield from the Floridan aquifer system exceeded $4 million. However, a comprehensive assessment of damage/economic loss to private property and public resources due to unsustainable yield from that regional karst aquifer has not been made. Uncalculated direct costs to home‐owners from damage attributed to those withdrawals are associated with destruction of homes from increased sinkhole formation, devalued waterfront property, and removal of diseased and dead trees. Examples of other uncalculated economic burdens resulting from unsustainable aquifer yield in the SE Coastal Plain include: (1) irreversible damage to the aquifer matrix and concomitant increased potential for groundwater contamination, (2) large‐scale wildfires with subsequent degradation of air quality, debilitation of transportation corridors, and destruction of timber, wildlife habitat and property, and (3) destruction of “protected” natural areas. This paper provides a general background of the regional Floridan aquifer system's karst characteristics, examples of known impacts resulting from ground water mining in the SE Coastal Plain, and examples of additional damage that may be related to unsustainable yield from the Upper Floridan aquifer. Costs of these impacts have not been calculated and are not reflected in the price users pay for ground water. Evidence suggests that the classic watershed management approach must be revised in areas with mined regional karst aquifers to include impacts of induced recharge from the surficial aquifer, and subsurface inter‐basin flow. Likewise, associated impacts to surface water and interrelated systems must be calculated. The true cost of groundwater mining to this and future generations should be determined using a multidisciplinary approach. 相似文献
604.
Philipp Balzer Klaus Peter Rippe Peter Schaber 《Journal of Agricultural and Environmental Ethics》2000,13(1-2):7-27
The 1992 incorporation of an article by referendum in the Swiss Constitution mandating that the federal government issue regulations
on the use of genetic material that take into account the dignity of nonhuman organism raises philosophical questions about
how we should understand what is meant by “the dignity of nonhuman animals,” and about what sort of moral demands arise from
recognizing this dignity with respect to their genetic engineering. The first step in determining what is meant is to clarify
the difference between dignity when applied to humans and when applied to nonhumans. Several conceptions of human dignity
should be rejected in favor of a fourth conception: the right not to be degraded. This right implies that those who have it
have the cognitive capacities that are prerequisite for self-respect. In the case of nonhuman organisms that lack this capacity,
respecting their dignity requires the recognition that their inherent value, which is tied to their abilities to pursue their
own good, be respected. This value is not absolute, as it is in the case of humans, so it does not prohibit breeding manipulations
that make organisms more useful to humans. But it does restrict morally how sentient animals can be used. In regard to genetic
engineering, this conception requires that animals be allowed the uninhibited development of species specific functions, a
position shared by Holland and Attfield, as opposed to the Original Purpose conception proposed by Fox and the Integrity of
the Genetic Make-up position proposed by Rolston. The inherent value conception of dignity, as here defended, is what is meant
in the Swiss Constitution article.
This paper is a slightly revised version of a paper that had been published in German in 1998 (“Menschenwürde vs. Würde der
Kreatur,” Freiburg i.Br.). 相似文献
605.
环保产业对人类社会的持续协调发展具有巨大的价值贡献 ,是战略性产业。人们应借鉴国际经验并结合国情 ,建立我国环保产业有效的调控激励机制 :从加强环保产业的驱动因素入手 ,制定有效的产业扶植政策 ,加强技术创新 ,构筑环保产业大市场格局 ,促进环保产业向深层次快速发展。 更多还原 相似文献
606.
皂素工业废水CODCr排放限值的研究 总被引:1,自引:1,他引:0
皂素工业是近几年来迅速发展的一个重要生物医药化工行业,我国皂素主产区位于南水北调中线工程水源汉江上游,其排放的大量高浓度含酸有机废水给水源保护带来严重威胁,急需制定我国的皂素工业水污染物排放标准.采用三段式两相厌氧为核心的二级生化组合工艺技术从实验室试验、现场工业性试验和示范工程三方面对皂素工业废水CODCr排放限值进行了研究,皂素废水二级生化处理出水中残留CODCr总量(以质量浓度计)约为400~500 mg/L,其中溶解性微生物代谢产物(SMP)质量浓度约为240~280 mg/L.综合考虑技术可达性和经济可行性,将现有企业CODCr排放限值规定为400 mg/L;为引导企业对废液综合利用,推进皂素行业清洁生产,规定新建企业和现有企业的第二时段的限值为300 mg/L.提出了丹江库区相应的CODCr总量指标及皂素规模限额.执行该标准后,全国每年可削减CODCr 71 400 t,其中南水北调中线工程水源汉江上游至少可削减60 690 t,可以满足中线调水水源区的环境保护要求. 相似文献
607.
In Finland, a new Government Decree on the Assessment of Soil Contamination and Remediation Needs (214/2007) came into force
on 1 June 2007. According to the Decree, natural baseline concentration levels should be taken into account when assessing
potential soil contamination and the need for remediation. This applies particularly in the case of toxic metallic elements,
since baseline concentrations may naturally be rather high. The new decree prescribes soil screening values for 52 substances
or groups of substances. The natural baseline concentrations have been taken into account in the definition of the screening
values for inorganic pollutants. The Geological Survey of Finland (GTK) carried out a nation-wide geochemical mapping of till
on a reconnaissance scale in 1983 and on a regional scale during 1984–1992. These surveys have provided information on natural
elemental distribution in subsoils of the glacial till. However, some important trace elements in regional mapping such as
arsenic are missing from the analysis, and subsoil samples do not reflect the diffuse anthropogenic input. Thus, GTK has continued
the survey work by determining geochemical baselines around suburban areas. Samples have been taken from humus, topsoil and
subsoil layers, and the soil parent material has covered sandy soils, glacial tills and fine-grained sediments. According
to the studies, a regional difference in the levels of arsenic and some other trace elements can be clearly seen, especially
in minerogenic soils. The results illustrate the importance of information on regional baseline concentrations while assessing
potential soil contamination. 相似文献
608.
北京市25种公路绿化植物及配置模式的绿量 总被引:1,自引:0,他引:1
计量研究公路绿地的生态服务功能有助于科学评估公路绿化的无形价值。以北京市顺义区顺平路(S305)的绿化植物群落为研究对象,运用WinScanopy For Canopy Analysis冠层分析仪采集数据,研究了公路绿化常见植物及配置模式的绿量率,并建立了25种公路绿化常见植物的绿量率模型,以期为公路绿化树种选择和群落配置提供基础分析与参考。结果表明:阔叶乔木的绿量率在3.02~4.80之间,针叶乔木的绿量率集中在4~6之间,灌木植物的绿量率较小,种植紧凑的绿篱绿量率达到3.94;不同配置模式的群落绿量率大小顺序依次为:针阔混交林>阔叶林>针叶林>灌木群落。其研究结果为公路绿化建设和绿地生态效益的计量提供了科学依据。 相似文献
609.
高寒草地土壤保持功能的风洞模拟及其定量评估 总被引:2,自引:0,他引:2
青藏高原高寒草地的土壤保持功能对于保护生态环境具有重要的作用。为了研究人类活动不同干扰方式对高寒草地土壤保持功能的影响,利用大型风洞,对不同干扰方式下高寒草甸、草原化草甸和高寒草原3个类型的土壤保持功能定量评估,以侵蚀率作为土壤保持功能的测度指标。实验结果表明,随着风速的增大,3个样品的土壤侵蚀率均呈现增大趋势,但不同处理下侵蚀率的增幅不同。当植被根系破坏后,土壤侵蚀率大小为高寒草甸<草原化草甸<高寒草原,说明,高寒草甸土壤的可蚀性低,高寒草原土壤的可蚀性高,极易遭到破坏。从总体来看,土壤保持功能的强弱依次为高寒草甸>草原化草甸>高寒草原。风蚀前后土壤中有机质和养分含量的变化分析表明,土壤有机质和养分含量显著下降,其中速效K2O的养分含量下降幅度最大。对3个草地类型单位面积土壤保持经济价值进行计算,计算主要包括保持有机碳、保持养分和减少土壤流失对河流湖泊淤积3个方面的价值。结果表明,高寒草原化草甸单位面积的土壤保持价值最高,其次为高寒草甸,高寒草原单位面积土壤保持价值最低。 相似文献
610.