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231.
Ä.P. Lino Grima Susan Horton Shashi Kant 《Environment, Development and Sustainability》2003,5(3-4):297-314
Can development occur without running down natural resources in an unsustainable way? The concept of natural capital offers a way for those with divergent views (ecologists and economists for example) to discuss this difficult question. Four aspects are examined in detail. First, the role of institutions in facilitating sustainable development is discussed, with examples from forestry. Then examples from (eco)tourism illustrate the potential – and limits – of applicability of the concept. Measurement issues for natural capital are then considered in detail. Finally, the concept is applied to agricultural strategy in fragile lands, where the tradeoff between the environment and development is likely to be most severe. Some implications for future research and policy are developed. 相似文献
232.
中国有机食品的生产和认证 总被引:9,自引:0,他引:9
中国的有机食品开发和认证工作起步于上个世纪末。经过近十年的发展,有机食品的开发行为已基本得到了社会各界的认可,更多的基地、企业、高校、科研单位以及政府部门都参与到这一新兴产业中,有机食品产业蓄势待发。目前,如何正确分析和处理有机食品开发过程中的一些问题以引导和促进该项事业的健康发展,已显得尤为重要。本文在总结近年来工作的基础上,提出了中国有机食品开发工作中存在的一些不足之处,希望能够起到抛砖引玉的作用,使更多的人参与到有机食品认证管理的讨论之中。 相似文献
233.
In recent years, churches across the world have become involved in dialogue on the theory and practice of sustainable development. A number of Western churches have expressed their concern about climate change and destructive living patterns, stressing the need for human beings to exercise the care for all creation based on a life of sharing and sacrifice. Some Orthodox churches, however, quite recently included the environmental issues in their agendas. While the Bases of Social Concept, a major doctrine of the Russian Orthodox Church adopted in 2000, for the first time emphasises the Churchs position in overcoming environmental crisis and presents a solid basis on which to build the future environmental strategy of the Church, the Ethiopian Orthodox Church has not yet drawn up a programme document that might serve as a framework for the Churchs current extensive activities in the field of biodiversity conservation and sustainable forestry practices. Hence, despite certain closeness of both institutions, there is the potential for strengthening their roles in promoting sustainable development, based on the Biblical concept that the Earth belongs to the Lord and humans are responsible stewards assigned the duty to work for creation and care for it. This paper seeks to demonstrate by means of comparable analysis between the two Churches, Orthodox in nature but different in rites and religious practices, that traditional, highly conservative faiths may serve as powerful instruments of spreading out the ideas of sustainable development as the basis of spiritual revival in the situation of the two concurrent and interrelated crises – spiritual and ecological.Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
234.
Concentrations of heavy metals (Pb, Zn, Cd, Cu) were determined in soils and vegetables (chrysanthemum, spinach and four cultivars of Chinese cabbage from the area adjacent to a Pb/Zn mine in Shaoxing, Zhejiang province, China, and compared with the Chinese National Standards for Soil Environmental Quality. The accumulation of heavy metals in cabbage cv. Siyuegreen was investigated at different distances from the center of the mine. The vegetable plantation soils were polluted with Pb, Cd, Cu and Zn, especially by Pb and Cd. The levels of Pb and Cd were 20 and 30 times higher than the permitted standards, indicating that this Pb/Zn mining area is unsuitable for agricultural use. Chinese cabbage, chrysanthemum and spinach had different enrichment coefficients. The enrichment coefficient of Cd from soil to roots of chrysanthemum was >80% and from roots to leaves of cabbage cv. Shanghaigreen was >120%. These vegetables were polluted by heavy metals and could not be regarded as safe for human consumption. Environmental accumulation of heavy metals in the vegetable plantation soils was proportional to heavy metal accumulation in vegetables and both were inversely proportional to the distance from the lead/zinc mine. 相似文献
235.
Bettinetti R Croce V Galassi S Volta P 《Environmental science and pollution research international》2006,13(1):59-66
- DOI: http://dx.doi.org/10.1065/espr2006.01.010
Background, Aims and Scope Although pp'DDT usage was strongly limited or banned in most parts of the world during the last three or four decades, the
parent compound, its homologues and their metabolites still occur at levels which might pose a risk for many ecosystem components.
A case of DDT pollution of industrial origin was discovered in 1996 in Lake Maggiore, the second largest (212 km2) and deepest
(370 m) lake in Italy, causing concern for wildlife and human health. The extensive monitoring of many biotic and abiotic
compartments which followed from 1998 in order to assess the pollution level and its trend in time, provided a great availability
of data referring to DDT contamination of the different fish species of the lake. In this study, the recent contamination
levels in selected fish species were compared to those measured in 1998 to evaluate the temporal pollution trend of the lake
and its natural recovery, given that no remediation measures were carried out on the contaminated soils and sediments in this
time span. Moreover, a modelling approach to test the equilibrium condition between water and pelagic fish species was used.
Analytical results of pp'DDT and pp'DDE concentrations in lake water were used as input data in the bioenergetic model by
Connolly & Pedersen (1988) to calculate concentrations in two fish species and to compare the predicted and the measured contamination.
Methods Sampling and analytical determination of DDT homologues in lake water: Five water sampling campaigns were carried out from
May 2002 to February 2004 in three sampling sites of Lake Maggiore. Suspended and dissolved pollutants were determined separately.
Quantitative DDT homologue analyses were performed by HRGC coupled with ECD detection by the external standard method. Single
water extracts were put together in correspondence with the stratification zones of the water column inferred on the basis
of the temperature profile to improve analytical sensitivity. Selection of fish data: Concentrations of DDT and DDE in fishes
were selected from recent literature (CIPAIS 2003, 2004). Bioaccumulation model: The bioenergetic model proposed by Connolly
& Pedersen (1988) was used to assess the bioaccumulation of pp'DDT and pp'DDE of Alosa fallax (landlocked shad) and Coregonus
spp. (whitefish), selected among the different species as representative of a secondary consumer level.
Results and Discussion The average concentrations of pp'DDT and pp'DDE in water to be used as input data in the bioenergetic model were obtained
considering all the concentrations measured at the three sampling stations in the epylimnion where the fish species considered
in this study spend most of their life. The resulting values were 0.05 and 0.16 ng/L for pp'DDT and pp'DDE, respectively.
Average measured pp'DDT and pp'DDE concentrations in landlocked shad were 0.81 +/- 0.39 and 1.69 +/- 0.71 mg/kg lipids, respectively,
and were 0.29 +/- 0.12 and 1.06 +/- 0.41 mg/kg lipids for the whitefish. Calculated and measured values turned out to be
in quite good agreement for pp'DDT, while measured pp'DDE concentrations were higher than expected on the basis of the bioenergetic
model in both species. Probably metabolic transformations of pp'DDT accumulated in fish tissues in the past are responsible
for the observed differences between calculated and expected pp'DDE concentrations in fish.
Conclusions Pelagic fishes of Lake Maggiore seem to maintain the DDT accumulated during their life time and the most efficient mechanism
responsible for the fish population recoveries is probably their generation changes; for this reason, equilibrium models cannot
be used until negligible pp'DDT concentrations are reached in fish tissues.
Recommendations and Outlook The limit proposed for pp'DDT in water by the EU Directive 2000/60, which will come in force in 2008, is 0.2 ng/L, four times
higher than the average concentration measured in Lake Maggiore waters. Nevertheless, concentrations measured in Lake Maggiore
fish were very close and sometimes exceeded the Maximum residue limits (MRLs) settled by the Italian legislation for foods
(0.1 mg/kg w.w. for fish containing 5–20% lipid). It seems, therefore, that the 'environmental quality standard' of 0.2 ng/L
cannot guarantee the suitability of fish for human consumption. 相似文献
236.
现行的林业行政执法体制有许多弊端,组建综合林业行政执法机构,成立综合执法队伍,统一林业执法权有其理论根据、法律依据和现实依据,这样整合了林业执法力量,加大了打击破坏森林资源违法犯罪活动的力度,还便于林业绿色事业的管理与发展,并对综合林业执法提出了一些具体设想. 相似文献
237.
云南个旧多金属矿区农田土壤-作物系统重金属污染现状——以乍甸镇为例 总被引:7,自引:0,他引:7
对云南个旧市乍甸镇农田土壤和农作物重金属污染现状进行了野外调查及评价。结果表明:农田土壤Pb、Zn、Cu、Cd、As质量比均超出GB 15618—1995《土壤环境质量标准》二级标准,Hg未检出,该地区农田呈现以As、Cd为主多种重金属复合污染。Pb、Zn、Cu、Cd、As土壤有效态质量比与土壤全量呈极显著正相关(p<0.01)。农作物中Cu、As质量比与土壤有效态Cu、As质量比无显著相关,Zn质量比与土壤有效态Zn呈极显著负相关(p<0.01),Cd、Pb质量比与土壤有效态Cd、Pb呈显著正相关(p<0.05)。89%的农作物As超标,油菜籽(Brassica napusL.)As质量比最高,均值达(23.04±14.33)mg/kg(鲜重,下同)。Pb超标率达72%,油菜籽Pb质量比最高,平均为(5.55±2.53)mg/kg。Zn、Cd超标率均为11.11%,超标最严重的油菜籽Zn质量比为(46.65±13.61)mg/kg,Cd质量比为(0.24±0.10)mg/kg。Cu超标率为5.55%,油菜籽Cu质量比最高,达(16.02±2.75)mg/kg。油菜籽对As、Pb、Zn、Cu、Cd的转移系数(农作物可食部分重金属质量比(鲜重)与土壤重金属质量比的比值)远高于其他作物。农作物对Pb、Zn、Cd、As的转移顺序依次为果实类、叶菜类、根茎类,对Cu的转移顺序为果实类、根茎类、叶菜类。农作物以As、Pb污染为主,总体属重度污染。聚类分析得出:油菜籽、青蒜(Allium ampeloprasumL.)和生菜(Lactuca sativaL.var.ramosaHort.)重金属污染严重,不适合在该地区继续种植和食用。 相似文献
238.
Perceived changes in well-being and happiness with gardening in urban organic allotments in Portugal
Urban allotment gardens (AG) in Portugal have increased in recent years, as in many other European countries and worldwide. The contribution of these gardens to the happiness and well-being of urban populations has been recognized, but evaluations of their benefits are still very scarce. The objective of this study was to evaluate this contribution, based on the urban organic AG of the Devesa Park in Vila Nova de Famalicão, Portugal. The sample included 65 gardeners who completed the self-administered questionnaires of Bem-Estar Pessoal (personal well-being scale), Felicidade Subjetiva (subjective happiness scale) and sociodemographic characteristics. Respondents were mainly adults under 65 years, married and academically well qualified and about half of them had a professional activity, with nearly one third being retired. They considered themselves happy with their life (Personal Well-being Index = 74.5%) and revealed an optimistic and positive attitude towards life, regardless of economic or social difficulties. The increased frequency of visits for gardening was positively related to a greater perception of subjective happiness. The gardeners who visited the AG more frequently considered themselves happier from a self-perspective and in comparison with peers. It can be suggested that urban organic AG represent a means for enhancing citizen well-being, contributing positively to their feelings of happiness and life satisfaction, changing behaviours and developing personal capacities. Beyond economic measures, urban AG can be recommended to capture the well-being of societies. 相似文献
239.
食物波动与效率是食物安全的重要研究内容。1993~2003年江西省平均食物生产全要素相对生产率为0.974,其规模效益基本上呈现常数规模效益与规模效益递增交替波动现象。灰色关联分析表明,粮食产量、油料产量、肉类产量、糖料产量等与食物总量具有显著关联性,其灰色关联序为:粮食产量>油料产量>肉类产量>糖料产量>禽蛋产量>水果产量>牛奶产量,所以要保证食物总量安全,必须首先保障粮食、油料、肉类等的生产。 相似文献
240.
为评估食品企业氨制冷系统所处的风险状态,文章在HAZOP方法和LOPA方法理论研究的基础上,将其组合应用于食品企业氨制冷系统的风险评估中,以提前识别可能导致事故的原因和后果,确定现有防控措施是否足够、有效,并将风险控制在可接受水平。通过对氨制冷系统中低压循环桶液位过高场景的实例分析,得出该场景下的剩余风险基本在企业可接受范围内,不需要增加独立安全仪表系统的结论,为食品企业安全管理决策提供了科学依据。 相似文献