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21.
Since the 1940s, some sectors of the sand dune barriers of Buenos Aires Province have been forested to fix the sand in the neighborhoods of resort villages. Man took advantage of the maritime climate and the shallow groundwater to introduce pine forests. Today, these forests reach more than 20 m in height and have developed soils of more than 0.05 m in thickness on former arid sands. Field data were referred to Landsat (TM) composite and Normalized Difference of Vegetation Index, NDVI, images to calculate forest density and covered area. Considering published tables of wood density for each species, the amount of total carbon storage was estimated on 318 t C ha-1 (Mg=106 g) in biomass and 86 t C ha-1 in soils. The three areas analyzed at Miramar, Necochea and Claromecó have captured 658,868 t of carbon in the last 50 years. It is estimated that 150,000,000 t C could be sequestered within temperate dune barriers of Argentina, Uruguay and Brazil. Besides this ecological point of view, there is an important socio-economic factor that cannot be excluded.Presented at and revised subsequent to the 4th LOICZ Open Science Meeting, Bahía Blanca, Argentina. October 1999.  相似文献   
22.
The paper calculates the implications of including monetary measurements of environmental emission changes for the welfare impacts of ecological tax reforms in Italy and Sweden. Taxes on emissions of SO2, NOx and CO2 are investigated. Country-specific computable equilibrium models are used for estimating net welfare changes of the introduction of these taxes, the incomes of which are used for reducing distorting labour taxes. The results indicate that the inclusion of environmental benefits reduces the costs of ecological tax reforms considerably for both countries, and may even turn into net welfare gains.  相似文献   
23.
Benefits-based management seeks to provide recreation benefits for recreation participants by managing the physical environments in which recreation occurs. This study investigates the relationship between benefits desired by visitors and the physical, social, and managerial characteristics of settings that facilitate realization of recreation benefits. Data such as perceived benefits from recreation experiences, setting attributes that significantly influenced perceived benefits, and sociodemographic variables were collected from 376 visitors to Sorak-san National Park in the eastern part of the Korean peninsula. Cluster analysis was used to group visitors' desired benefits into 12 domains: relationship with nature/scenery, escaping pressure, learning about nature, family togetherness, introspection, exploration, autonomy/achievement, being with friends, leading others, skills/learning, risk taking, and meeting/observing new people. Multiple regression was used to link benefit domains with the characteristics of settings. The social attribute of recreation settings was linked to eight of the ten benefit domains. There were two statistically strong multiple regression correlations: (1) between domain of “relationship with nature /scenery” and the attributes “forest/water,”“attractive nature,” and “facility/maintenance” and (2) between the domain of “escaping pressure” and the attributes “attractive nature” and “social.” The results of this study are useful to managers in their efforts to provide recreation opportunities for visitors to achieve beneficial outcomes.  相似文献   
24.
: Substantial reductions in municipal water use are feasible without reducing the quality of life. If conservation measures are preplanned, properly engineered, and coordinated, reductions in utility bills for water, waste water, and energy are estimated at $30+per person per year. Installation of devices to reduce water use, engineering plans to prevent malfunctioning of collecting sewers, and engineered process modifications of treatment facilities must be coordinated to achieve full benefits of water conservation. Pollutant discharges to the aquatic environment are reduced in direct proportion to the reduction in water use.  相似文献   
25.
This study estimates efficient nitrogen load reductions to the Stockholm archipelago, a Swedish coastal zone in the Baltic Sea, and compares these with politically determined and implemented nitrogen abatement programs. The region is relatively well equipped with necessary data, and a simple programming model is constructed. The results show a large divergence in efficient nitrogen reductions, mainly due to the divergences in benefit estimates from water quality improvements in the archipelago. However, the results need to be interpreted with caution due to all uncertainties related to predicting net values from changes in nitrogen load to a coastal zone. In spite of this, it is still of policy relevance to infer results which show that the politically determined target coincides with an efficient nitrogen reduction at relatively low benefit estimate, but that actual net benefits could be increased from a reallocation of abatement measures towards more low cost measures.  相似文献   
26.
发展林业碳汇是应对全球气候变化及实现中国2060年碳中和的重要举措。基于改进的Faustmann-Hartman模型,以中国南方浙江、福建和江西三个省份杉木人工林为研究对象,使用时间序列模型拟合并预测中国碳排放权交易市场的碳汇价格,通过蒙特卡洛模拟确定最优轮伐期及碳汇收益。研究结果表明:(1)依次纳入木材收益、地上生物量碳汇收益和死亡有机质碳汇收益时,杉木人工林的最优轮伐期分别为21.85年、22.98年和22.88年;(2)上述三种情景下,林地期望价值的净现值分别为20408.20元/hm2、24587.29元/hm2和28101.11元/hm2;(3)全面考虑包含死亡有机质碳库在内的林业碳汇效益,能够稳定提高林地所有者收益约7.02%~21.61%。此外,应进一步考虑多轮伐期下税收政策及自然风险等因素对碳汇营林的影响,这是确定最优轮伐期和碳汇收益后续研究值得重视的问题。  相似文献   
27.
胡东滨  林媚  陈晓红 《中国环境科学》2022,42(11):5447-5456
基于2000~2019年浙江和安徽26个地级市的面板数据,使用合成控制法定量分析新安江3轮横向生态补偿试点政策对其水环境效益的总体性和结构性影响结果表明:政策效果在时间上存在异质性。第1、2轮政策试点显著的提升了新安江流域整体的水环境,但第3轮试点对上游水环境的影响是负的。政策效果在空间上存在异质性。流域横向生态补偿政策使下游的生物多样性价值平均提高了0.068亿元,但使上游生物多样性价值平均降低了0.015亿元。政策效果在结构上存在异质性。通过对水环境效益的结构性分解,发现横向生态补偿政策使新安江流域的水质净化能力价值平均提高了31.874亿元,但使其产品供给价值平均下降了13.402亿元。政策效果存在预期效益。流域横向生态补偿的政策效果在政策正式实施前2年已经出现。  相似文献   
28.
在综述煤层气对于煤矿安全生产以及环境危害的基础上,从保护环境、缓解能源紧张、延长煤层气的产业链、减少瓦斯危害等多个角度综合分析了煤层气开发所带来的巨大效益,并以黔西北煤矿为例,叙述了煤层气的资源量现状及其地质特征等基本情况。简述了目前我国煤层气的开发现状,并提出了四条增产措施,这些措施必将对推动贵州省经济与环境的可持续发展,加快贵州省工业强省步伐起到积极作用。  相似文献   
29.
Achieving Integrative, Collaborative Ecosystem Management   总被引:3,自引:0,他引:3  
Abstract:  Although numerous principles have been identified as being important for successfully integrating social and ecological factors in collaborative management, few authors have illustrated how these principles are used and why they are effective. On the basis of a review of the ecosystem management and collaboration literature, we identified eight factors important for integrative, collaborative ecosystem management—integrated and balanced goals, inclusive public involvement, stakeholder influence, consensus group approach, collaborative stewardship, monitoring and adaptive management, multidisciplinary data, and economic incentives.We examined four cases of successful ecosystem management to illustrate how the factors were incorporated and discuss the role they played in each case's success. The cases illustrate that balancing social and ecosystem sustainability goals is possible. Collaborative efforts resulted in part from factors aimed at making plans economically feasible and from meaningful stakeholder participation in ongoing management. It also required participation in monitoring programs to ensure stakeholder interests were protected and management efforts were focused on agreed-upon goals. Data collection efforts were not all-inclusive and systematic; rather, they addressed the ecological, economic, and social aspects of key issues as they emerged over time. Economic considerations appear to be broader than simply providing economic incentives; stakeholders seem willing to trade some economic value for recreational or environmental benefits. The cases demonstrate that it is not idealistic to believe integrative, collaborative ecosystem management is possible in field applications.  相似文献   
30.
Allocating water to different uses implies trading off the benefits perceived by different sectors. This paper demonstrates how visualising the trade-offs implied by the best performing water management options helps balance water use benefits and find sustainable solutions. The approach consists of linking a water resources model that can simulate many management policies and track diverse measures of system performance, to a many-objective evolutionary optimisation algorithm. This generates the set of Pareto-optimal management alternatives for several simultaneous objectives. The relative performance of these efficient management alternatives is then visualised as trade-off curves or surfaces using visual analytic plots. Visually assessing trade-offs between benefits helps select policies that achieve a decision-maker-selected balance between different metrics of system performance. We apply this approach to a multi-reservoir water resource system in Brazil's semi-arid Jaguaribe basin where current water allocation procedures favour sectors with greater political power and technical knowledge. The case study identifies promising reservoir operating policies by exploring trade-offs between economic, ecological and livelihood benefits as well as traditional hydropower generation, irrigation and water supply. Results show optimised policies can increase allocations to downstream uses while increasing median land availability for the poorest farmers by 25%.  相似文献   
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