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561.
Linda A. Joyce Curtis H. Flather Patricia A. Flebbe Thomas W. Hoekstra Stan J. Ursic 《Environmental management》1990,14(4):489-500
The impact of timber management and land-use change on forage production, turkey and deer abundance, red-cockaded woodpecker
colonies, water yield, and trout abundance was projected as part of a policy study focusing on the southern United States.
The multiresource modeling framework used in this study linked extant timber management and land-area policy models with newly
developed models for forage, wildlife, fish, and water. Resource production was integrated through a commonly defined land
base that could be geographically partitioned according to individual resource needs. Resources were responsive to changes
in land use, particularly human-related, and timber management, particularly the harvest of older stands, and the conversion
to planted pine. 相似文献
562.
实施“新昆明”规划与建设,滇池盆地土地利用状况将有较大的改变,无疑会产生一系列生态后果。为此,需加强恢复天然湿地,大幅减少人工湿地以保护滇池,尽早开展关于昆明原有高原湖泊景观保护的研究。采取措施克服“水泥化”带来的负面影响并解决好城市原有水系的问题。 相似文献
563.
环境补偿制度——解决环境问题的经济手段之一 总被引:4,自引:0,他引:4
为了保护环境,使环境资源可持续利用,应该建立环境补偿制度。环境补偿制度是解决环境问题的有效手段之一。本文从环境补偿的概念出发,对环境补偿制度的理论基础,建立目的、征收原则及对象等内容进行了探讨。 相似文献
564.
周慧晶 《辽宁城乡环境科技》2007,27(2):47-49
介绍了用石墨炉(无火焰)原子吸收光谱法直接测定饮用水、地表水及废水中痕量钼的原理、过程,讨论了实验条件的优化、线性范围的选择,并对检出限、精密度和准确度做出评估。对钼标准物质(编号GBW199041)进行测定,测定结果与标准值相吻合。该方法测定的线性范围为0.0047mg/L-0.1000mg/L,检测限为0.0001mg/L,相对标准差为0.8%~1.6%,回收率为101%~107%,具有线性范围宽,简单,快速,准确等特点,在饮用水、地表水及废水中痕量钼的检测中具有很好的适用性。 相似文献
565.
EcologicalplanningforlanduseandruraldevelopmentofTaojiangCountyOuyangZhiyun;WangRusong;JasonWeisman(ResearchCenterforEco-Envi... 相似文献
566.
567.
568.
Optimizing carbon sequestration in commercial forests by integrating carbon management objectives in wood supply modeling 总被引:2,自引:0,他引:2
Charles P.-A. Bourque Eric T. Neilson Chris Gruenwald Samantha F. Perrin Jason C. Hiltz Yvon A. Blin Geoffrey V. Horsman Matthew S. Parker Christie B. Thorburn Michael M. Corey Fan-rui Meng D. Edwin Swift 《Mitigation and Adaptation Strategies for Global Change》2007,12(7):1253-1275
This paper provides a methodology for generating forest management plans, which explicitly maximize carbon (C) sequestration at the forest-landscape level. This paper takes advantage of concepts first presented in a paper
by Meng et al. (2003; Mitigation Adaptation Strategies Global Change 8:371–403) by integrating C-sequestration objective functions in existing
wood supply models. Carbon-stock calculations performed in WoodstockTM (RemSoft Inc.) are based on C yields generated from volume table data obtained from local Forest Development Survey plots
and a series of wood volume-to-C content conversion factors specified in von Mirbach (2000). The approach is used to investigate the impact of three demonstration forest-management scenarios on the C budget in a
110,000 ha forest in south-central New Brunswick, Canada. Explicit demonstration scenarios addressed include (1) maximizing
timber extraction either by clearcut or selection harvesting for greatest revenue generation, (2) maximizing total C storage
in the forest landscape and in wood products generated from harvesting, and (3) maximizing C storage together with revenue
generation. The level of clearcut harvesting was greatest for scenario 1 (≥15 × 104 m3 of wood and ≥943 ha of land per harvesting period), and least for scenario 2 (=0 m3 per harvesting period) where selection harvesting dominated. Because softwood saw logs were worth more than pulpwood ($60 m−3 vs. $40 m−3) and were strategic to the long-term storage of C, the production of softwood saw logs exceeded the production of pulpwood
in all scenarios. Selection harvesting was generally the preferred harvesting method across scenarios. Only in scenario 1 did levels of clearcut harvesting occasionally exceed those of selection harvesting, mainly in the removal of old, dilapidated
stands early in the simulation (i.e., during periods 1 through 3). Scenario 2 provided the greatest total C-storage increase over 80 years (i.e., 14 × 106 Mg C, or roughly 264 Mg ha−1) at a cost of $111 per Mg C due to lost revenues. Scenarios 3 and 1 produced reduced storage rates of roughly 9 × 106 Mg C and 3 × 106 Mg C, respectively; about 64% and 22% of the total, 80-year C storage calculated in scenario 2. The bulk of the C in scenario 2 was stored in the forest, amounting to about 76% of the total C sequestered. 相似文献
569.
570.
近年来,随着我国经济建设的进程不断加快,城市生态破坏问题逐渐显现,人们赖以生存的自然生态环境遭到了非常严重的破坏。保护好生态环境,是保证经济稳定、健康和可持续发展的重要前提。由于城市人口密集,生态系统脆弱,受到破坏后很难恢复,而且城市系统的生态恢复工作只能建立在现有的城市规模和城市特征的基础之上,很难有较大的改变。因此,研究和探讨城市生态功能区的规划,对于城市环境和经济建设环境的改善都具有很重要的意义。 相似文献