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991.
Morani A Nowak DJ Hirabayashi S Calfapietra C 《Environmental pollution (Barking, Essex : 1987)》2011,159(5):1040-1047
Highest priority zones for tree planting within New York City were selected by using a planting priority index developed combining three main indicators: pollution concentration, population density and low canopy cover. This new tree population was projected through time to estimate potential air quality and carbon benefits. Those trees will likely remove more than 10 000 tons of air pollutants and a maximum of 1500 tons of carbon over the next 100 years given a 4% annual mortality rate. Cumulative carbon storage will be reduced through time as carbon loss through tree mortality outweighs carbon accumulation through tree growth. Model projections are strongly affected by mortality rate whose uncertainties limit estimations accuracy. Increasing mortality rate from 4 to 8% per year produce a significant decrease in the total pollution removal over a 100 year period from 11 000 tons to 3000 tons. 相似文献
992.
Coastal deforestation in the Ayeyarwady Delta, Myanmar (formerly Burma) is addressed through the promotion of native-species
mangrove plantations on cleared land formerly sustaining natural mangrove forests. To date there are no attempts to determine
the optimal mangrove plantation strategy to maximize economic returns for private or communal plantation owners. We integrated
empirical biological and economic data to suggest optimal mangrove plantation strategies in the region. We censused 4-yr oldAvicennia officinalis mangrove plantations in two townships to calculate survival and growth rates of mangroves planted using different techniques
across an inundation gradient. We used the calculated rates to forecast the production of fuelwood, poles and posts at 10,
13 and 15 yr after establishment. We calculated the compound rate of growth for the three commodities over a 7-yr period,
and then forecast commodity price for the same harvestintervals. Integration of those parameters in our model led us to conclude
that both profit and the internal rate of return would be greatest for plantations of seedlings raised in polyethylene bags
as opposed to bare-root or direct propagule planting. Therefore, the use of potted seedlings should be promoted, despite higher
initial costs. The optimal rotation period varies according to ground level and planting technique. Optimizing economic returns
for coastal plantations does not necessarily require a sacrifice of ecological benefits.
Due to a discrepancy between official conversion quotes and local real value no conversion estimate in USD is given. 相似文献
993.
Coastal deforestation in the Ayeyarwady Delta, Myanmar (formerly Burma) is addressed through the promotion of native-species
mangrove plantations on cleared land formerly sustaining natural mangrove forests. To date there are no attempts to determine
the optimal mangrove plantation strategy to maximize economic returns for private or communal plantation owners. We integrated
empirical biological and economic data to suggest optimal mangrove plantation strategies in the region. We censused 4-yr oldAvicennia officinalis mangrove plantations in two townships to calculate survival and growth rates of mangroves planted using different techniques
across an inundation gradient. We used the calculated rates to forecast the production of fuelwood, poles and posts at 10,
13 and 15 yr after establishment. We calculated the compound rate of growth for the three commodities over a 7-yr period,
and then forecast commodity price for the same harvest intervals. Integration of those parameters in our model led us to conclude
that both profit and the internal rate of return would be greatest for plantations of seedlings raised in polyethylene bags
as opposed to bare-root or direct propagule planting. Therefore, the use of potted seedlings should be promoted, despite higher
initial costs. The optimal rotation period varies according to ground level and planting technique. Optimizing economic returns
for coastal plantations does not necessarily require a sacrifice of ecological benefits.
Due to a discrepancy between official conversion quotes and local real value no conversion estimate in USD is given. 相似文献
994.
论述了林业生态环境评价的概念、特点、原则、内容、指标和标准等,构建出林业生态环境评价的基本框架,并提出了存在问题和建议。着重指出,林业生态环境的价值多重性决定了林业生态环境评价的特殊性和复杂性。 相似文献
995.
Are Life Patents Ethical? Conflict between Catholic Social Teaching and Agricultural Biotechnology's Patent Regime 总被引:1,自引:1,他引:0
Keith Douglass Warner 《Journal of Agricultural and Environmental Ethics》2001,14(3):301-319
Patents for genetic material in theindustrialized North have expandedsignificantly over the past twenty years,playing a crucial role in the currentconfiguration of the agricultural biotechnologyindustries, and raising significant ethicalissues. Patents have been claimed for genes,gene sequences, engineered crop species, andthe technical processes to engineer them. Mostcritics have addressed the human and ecosystemhealth implications of genetically engineeredcrops, but these broad patents raise economicissues as well. The Catholic social teachingtradition offers guidelines for critiquing theeconomic implications of this new patentregime. The Catholic principle of the universaldestination of goods implies that genes, genesequences, and engineered crop varieties areineligible for patent protection, although theprocesses to engineer these should be eligible.Religious leaders are likely to make a moresubstantive contribution to debates aboutagricultural biotechnology by addressing theselife patents than by speculating that geneticengineering is ``playing God.' 相似文献
996.
中国西部贫困地区可持续发展研究 总被引:22,自引:2,他引:20
赵曦 《中国人口.资源与环境》2001,11(1):82-86
本文探讨了贫困与可持续发展的相互关系。在系统阐释中国西部贫困地区可持续发展面临的现实问题、困难和障碍的基础上,着重围绕西部贫困地区可持续发展的基本内容和实施途径进行了综合性的分析和研究。 相似文献
997.
Effects of Land Use Changes on the Landscape Composition: A Comparison Between Finnish and Russian Karelia 总被引:1,自引:0,他引:1
Kimmo Saarinen Juha Jantunen Sanna Saarnio Karri Kuitunen Olli Marttila 《Environment, Development and Sustainability》2001,3(4):265-274
During the last 50 years the practising and intensity of agriculture and forestry have differed considerably between Finnish and Russian Karelia. We studied the effects of different land use practices on the landscape composition in the two countries using the road transect sampling along four study routes (99-121 km) between 1997 and 1999. Effective environmental management in Finland has resulted in more distinct agricultural land types, more even distribution of the different age classes of forests, and the higher abundance of coniferous forests. Fields (mean percentage of the landscape: Finland 28%, Russia 13%), clearcuts and sapling stands (15%, 6%), and young forests (23%, 9%) were more typical elements of the Finnish landscape, whereas settlements (9%, 13%), semi-natural grasslands (3%, 7%), and mature forests (20%, 49%) were more characteristic of the Russian landscape. Landscape-level differences between the two countries may have various effects on the diversity of fauna and flora inhabiting Finnish and Russian Karelia. 相似文献
998.
油品储罐区风险评价技术研究 总被引:5,自引:3,他引:2
本文通过分析影响储罐安全的五大因素18项指标,系统建立了单个油品储罐的安全评价指标体系,采用层次分析-模糊综合评价方法,实现单个油品储罐的安全状况分级。并结合区域定量风险评价方法,实现对油品储罐区的整体风险评价。以某油品储罐区为例,利用建立的指标体系与区域风险评价方法,给出了单个储罐安全等级以及储罐区个人风险等值线分布图和社会风险曲线。更全面的给出了储罐区单个储罐与罐区整体不同层次的风险状况,为油品储罐区规划,管理及事故预防和应急救援提供依据。 相似文献
999.
Studies of coordination in human networks have typically presented models that require stable working relationships. These models cannot be applied to emergency response management, which demands distributed coordination in volatile situations. This paper argues that changes to interconnectedness of nodes in a network may have implications for the potential to coordinate. A social network‐based coordination model is proposed to explore an organizational actor's state of readiness in extreme conditions. To test this hypothesis, the study investigates survey data from state law enforcement, state emergency services and local law enforcement, presenting agency‐based (macro) and cross‐agency (micro) analysis on 224 completed questionnaires. The main findings are: (i) there is a positive correlation between network connectedness and the potential to coordinate; (ii) the concept of tiers within an emergency response network may exist and be characterized by the sub‐network with which an organization associates; (iii) a range or threshold characterizes how interconnected an organization at a given tier should be. 相似文献
1000.