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221.
Economic growth is frequently touted as a cure for environmental ills, particularly for those in Third World countries. Here we examine that paradigm in a case study of Alberta, Canada, a wealthy, resource-rich province within a wealthy nation. Through provincial-scale datasets, we examine the increasing pressures of the forest, petroleum, and agricultural industries upon the ecosystems of Alberta within management, economic, and political contexts. We advance the thesis that economic activity leads to environmental degradation unless ecosystem-based management is integrated into economic decision making. Agricultural lands cover 31.7%, and forest management areas leased to industry cover 33.4% of Alberta; both continue to increase in extent. The rate of logging (focused on old-growth by government policy) continues a decades-long exponential rise. Current Alberta annual petroleum production is 52.5 million m3 crude oil and 117 billion m3 of gas. As of early 1999, there were approximately 199,025 oil and gas wells and a conservative total of approximately 1.5-1.8 million km of seismic lines in Alberta. Fire occurrence data indicate no downward trends in annual area burned by wildfire, which may be characterized as driven by climate and inherently variable. When logging and wildfire are combined, the annual allowable cut in Alberta is unsustainable, even when only timber supply is considered and the effects of expanding agriculture and oil and gas activities are ignored. Ecosystem degradation in Alberta is pervasive and contrasts prominently with a high standard of living. A wealth of ecological data exists that indicates current resource-based economic activities are non-sustainable and destructive of ecosystem health yet these data are not considered within the economic decision making process. Given the complex, compounded, and increasing ecosystem perturbations, a future of unpleasant ecological surprises is likely. We conclude with tentative predictions as to where current trends in Alberta may lead if decisions biased against ecosystems continue. 相似文献
222.
徐礼煜 《长江流域资源与环境》1993,2(4):374-378
由于人口的增长,人们对粮食、烧柴的需求与日俱增,致使森林面积减少,土壤等自然资源退化,生态环境恶化。对此于20世纪70年代提出了“复合农林业(Agroforestry)”,并发展成一门新兴的学科。它有意识地将多年生木本植物与农作物或家畜结合起来,在为农村提供烧柴、木材、饲料、粮食的同时,又可保持土壤肥力,达到持久农业的目的。它对我国大面积山丘地区自然资源的综合利用与保护有着重要的意义。 相似文献
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225.
Cecilia Akselsson Olle Westling Harald Sverdrup Johan Holmqvist Gunnar Thelin Eva Uggla Gunnar Malm 《Water, Air, & Soil Pollution: Focus》2007,7(1-3):201-210
The effects of harvesting on the long-term mass balances of calcium (Ca), magnesium (Mg) and potassium (K) were evaluated
on a regional level in Sweden. A new high-resolution weathering database was used together with estimates of total deposition,
losses through harvest and leaching. Estimates were made for pine and spruce separately and for two harvesting intensity scenarios:
stem harvesting and whole-tree harvesting. The mass balance calculations showed net losses of Ca and Mg in almost the whole
country for both scenarios. The losses were smaller for pine than for spruce. The K balances were mainly positive for pine
but negative for spruce. Leaching was a main factor in the mass balances, especially for Ca and Mg. Whole-tree harvesting
in spruce forests led to substantially higher net losses of K and Ca than stem harvesting, according to the calculations.
In the whole-tree harvesting scenario in spruce forests the estimated yearly net losses of Ca, Mg and K corresponded to at
least 5%, 8% and 3% of the pools of exchangeable base cations, respectively, at 25% of the analysed sites. If losses of this
magnitude continue the depletion of the pools of Ca, Mg and K may lead to very low base saturation of the soils, possibly
accompanied by negative effects on soil fertility, runoff water quality, tree vitality and tree growth within a forest rotation
in parts of Sweden. Avoiding whole-tree harvesting can improve the situation substantially for K, but the losses of Ca and
Mg will still be significant. 相似文献
226.
本文选取小山口村、魏城村和南垛庄铺三个林权改革试点村作为调查对象,通过描述统计、交叉列联表分析和Ridit分析,就林权改革的方式、林改对经济和环境产生的影响及林权流转三个方面的问题对山东临沂市的集体林权制度改革现状展开调查研究。分析发现,在历经3年的林改中,临沂市始终坚持尊重实际、区别对待,灵活选择林权改革的方式,使当地的林权制度改革受到村民的欢迎。此外,林权改革后,当地的经济收入和生态环境及对林业的投入均有不同程度的提高和改善,村民的营林、护林积极性也大大增加。但是在涉及到林权流转方面的问题时,大部分的村民不能清楚认识到林权的价值,从而使落实处置权的目标短期内难以实现。 相似文献
227.
林业碳汇项目基准线和监测方法学及应用分析——以贵州省贞丰县林业碳汇项目为例 总被引:1,自引:0,他引:1
气候变化给全球社会经济发展带来了重大影响,林业碳汇在适应和减缓气候变化、促进可持续发展三方面的重要作用日益被世界各国所认可。林业碳汇项目实施的难点在于准确掌握林业碳汇项目设计的规则、标准体系,重点在于基准线判别、碳汇计量、监测的方法学和工具。本文系统介绍了国际清洁发展机制造林再造林(CDM A/R)项目方法学和国内碳汇造林项目方法学、标准体系等最新成果,并以贵州省贞丰县林业碳汇项目为例,分析了基准线和监测方法学在林业碳汇项目开发设计中的实际应用。 相似文献
228.
葫芦岛市水土流失防控体系建设研究 总被引:1,自引:0,他引:1
杨卓 《中国环境管理干部学院学报》2011,(5):33-35
分析了葫芦岛市水土流失现状及水土保持方面存在的问题,提出水土流失防控体系建设策略。建议采取水土流失分区治理、工程措施、林业措施、管理措施等建设葫芦岛市水土流失防控体系。 相似文献
229.
Application of optimal harvesting decision model to the analysis of Chinese forestry economic policy
This paper firstly extends the single period forest optimal harvesting decision model to infinite periods,in order to indicate how to determine the optimal rotation period aimed at maximizing forest revenue in all directions when repeat planting and harvesting trees on the same plot of earth till infinite future.The study also analyzes the influence of discounted rates,timber price,harvesting costs,planting costs,and tax on the determination of optimal rotation period;and how the optimal rotation period will change when we introduce the factors of continuously rising timber price and ecological revenue.Secondly,the authors introduce the intergenerational equity principle into the above model to design a resource-exploiting mode which satisfies bom the dynamic efficiency principle and the intergenerational equity principle.Last but not least,the research applies the above model to the analysis of Chinese forestry economic policy and explains the economic theory of institutions such as Government Purchasing Ecological Forest,Tree Compensation,and Forestry Subsidization,which provides a necessary theoretical foundation for future application of these new institutions.Besides,in regard to mis theoretical framework,the authors analyze the necessity of the Natural Forest Protection and Grain for Green projects which are currently being implemented in China.We also point out the emphasis of work to insure the project sustainable and successful.Finally,the research discusses the enterprise’s incentive to over-the-quota harvesting and the government’s means of restricting such behavior,which highlights the fact mat improved supervision and higher penalties are helpful in restricting over-the-quota harvesting. 相似文献