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1.
Land degradation is a global problem that seriously threatens human society. However, in China and elsewhere, ecological restoration still largely relies on a traditional approach that focuses only on ecological factors and ignores socioeconomic factors. To improve the effectiveness of ecological restoration and maximize its economic and ecological benefits, a more efficient approach is needed that provides support for policy development and land management and thereby promotes environmental conservation. We devised a framework for assessing the value of ecosystem services that remain after subtracting costs, such as the opportunity costs, costs of forest protection, and costs for the people who are affected by the program; that is, the net value of ecosystem services (NVES). To understand the difference between the value of a resource and the net value of the ecosystem service it provides, we used data on VES, timber sales, and afforestation costs from China's massive national afforestation programs to calculate the net value of forest ecosystem services in China. Accounting for the abovementioned costs revealed an NVES of ¥6.1 × 1012 for forests in 2014, which was 35.9% less than the value calculated without accounting for costs. As a result, the NVES associated with afforestation was 55.9% less than the NVES of natural forests. In some regions, NVES was negative because of the huge costs of human-made plantations, high evapotranspiration rates (thus, high water opportunity costs), and low forest survival rates. To maximize the ecological benefits of conservation, it is necessary to account for as many costs as possible so that management decisions can be based on NVES, thereby helping managers choose projects that maximize both economic and ecological benefits. 相似文献
2.
为了研究近断层地震作用下桥梁合理的最小搭接长度,防止落梁破坏,基于有限元软件 ANSYS 建立了连续刚构桥三维有限元模型;考虑了近断层和断层处地震动以及结构弹塑性特征对高墩连续梁桥最小搭接长度的影响;基于国内外抗震设计规范,分析了远场、近断层和断层处地震动下结构的最小搭接长度需求。针对该桥分析, 研究结果表明：根据各国抗震规范要求,中国和日本规范相对较保守,其搭接长度约为美国规范计算结果 2 倍和 1.5 倍;考虑近断层地震的最小搭接长度满足《公路桥梁抗震设计规范》要求,而地表破裂的跨断层地震作用下最小搭接长度需求超出规范要求,跨断层桥梁应采用防落梁措施;搭接长度与桥梁结构设计参数(跨径,墩高和材料等)和地震动强度指标(PGA,断层错位,PGV 和 PGV/PGA 等)有关。 相似文献
3.
Yang Guo Muhammad Javed Xiaoyan Li Shixiong Zhai Zaisheng Cai Bi Xu 《Advanced Sustainable Systems》2021,5(1)
Solar‐driven interfacial water evaporation is a promising strategy to produce clean water by effectively converting abundant solar energy into localized heat. However, many previously reported interfacial evaporation systems are separate and costly. In this work, an all‐in‐one interfacial water evaporator with flexibility, low‐cost, and large‐scale production based on electrostatic flocking technology is proposed. Hydrophilic microfibers (flocks) are vertically planted on the upper side of the textile substrate to enhance the light trapping for photothermal conversion and lower the latent heat for more efficient evaporation. On the other side of the textile, a highly dense and vertically aligned array of hydrophobic flocks are prepared to form a continuous air layer, reducing heat conduction from absorber to bulk water. Taking advantage of those features, the all‐in‐one evaporator achieves a good evaporation rate of 1.32 kg m−2 h−1 for pure water and 1.10 kg m−2 h−1 for seawater. Simultaneously, the evaporator demonstrates resistance to salt accumulation, resulting in its stability in brine. This all‐in‐one evaporator represents an innovative way for designing interfacial evaporators and a convenient approach to mitigate the global freshwater scarcity. 相似文献
4.
WANG Xiangrong YONG Yi ZHANG Hao WANG Pingjian WANG Shoubing CHEN Weizhen WANG Shixiong HO Hing Hon 《Frontiers of Environmental Science & Engineering》2008,2(2):178
The background, concept, connotation, principles, and methods of eco-planning for an Eco-Demonstration Park (EDP) and sustainability were examined based on a case study of the Luhua EDP in the Chongming Island of Shanghai, China, which is an important part of Shanghai Eco-city planning and construction in the 21st century. By analyzing natural, social and economic conditions, calculating population using the land capacity eco-model, eco-function zoning, and eco-construction, an innovative eco-industrial structure and technical chain were formulated. A comprehensive eco-planning scheme for the EDP was proposed, including planning and management strategies for subsystems of efficient industry, good quality human settlement, high standard eco-construction and eco-tourism as well as effective environmental protection and attractive landscape. The EDP should be an area with coordinated and sustainable economic, social and environmental subsystems. Eco-planning for the EDP should be a very important part of eco-city planning and sustainability. The paper aims to set up a theoretical framework and practical basis for eco-planning and promoting harmony between human and nature. 相似文献
5.
轮胎产业作为传统制造行业,在创造巨大经济效益的同时,也带来了巨大的环境问题。为了分析轮胎产业的潜在环境影响,寻找轮胎的减排减能潜力,基于全生命周期理论,以半钢子午线轮胎为研究对象,考虑轮胎生产、运输、使用直至废轮胎利用的生命周期闭环全过程,建立碳排放模型和能量消耗模型,并构建回收利用阶段的碳减排—削减清单和能量排放—削减清单,对比分析废轮胎连续低温热解、间歇低温热解和催化裂解的碳减排量、碳减排率、净碳盈余指标和能量削减量、能量削减率、净能量盈余指标。结果表明：1 t轮胎在整个生命周期中,共计消耗了3.52×105 MJ一次能源,排放了1.01×104 kg二氧化碳;在轮胎整个生命周期中,运输和使用阶段的碳排放量以及能量消耗最大。针对轮胎各阶段环境影响分析,可知轮胎生产阶段关键碳排放元素包括炭黑、电、合成橡胶以及钢丝帘线等;关键能源消耗元素包括合成橡胶、炭黑以及蒸汽等;3种资源利用方式中连续低温热解的碳回收效果最好,催化裂解的能量回收效果最好;再生回收物是废轮胎碳削减和能量削减的最主要的贡献来源。 相似文献
6.
Xia Xianwang Jiao Chentai Song Shixiong Zhang Ling Feng Xingyun Huang Qingxu 《Environmental science and pollution research international》2022,29(38):57437-57452
Environmental sustainability is the foundation and of great significance for the sustainable development of urban agglomerations. Taking the Beijing-Tianjin-Hebei urban agglomeration as an example, we developed a method to effectively assess long-term regional environmental sustainability based on the Google Earth Engine (GEE) platform. We used the GEE to obtain 5206 Landsat remote sensing images in the region from 1983 to 2016 and developed the comprehensive environmental index (CEI) to assess regional environmental sustainability based on the theme-oriented framework proposed by the United Nations Commission on Sustainable Development. We found that the environmental sustainability of the urban agglomeration showed a trend of first rising, then falling, and then rising again in the past 30 years. The average CEI increased from 0.621 to 0.631 from 1985 to 1990, dropped to the lowest value of 0.618 in 2000, and then rose to the highest value of 0.672 in 2015. In particular, the extent of areas in which environmental sustainability improved (56% of the region) was greater than the extent of areas in which environmental deterioration occurred. The environmental sustainability of Hengshui, Xingtai, and Cangzhou in the southeast of the region has been significantly improved. The method proposed in this study provides an automatic, rapid, and extensible way to assess regional environmental sustainability and provides a scientific reference for improving the sustainability of the regional environment.
相似文献7.
Xiangrong Wang Yi Yong Shixiong Wang Hao Zhang Hing Hon Ho Pingjian Wang Shoubing Wang Weizhen Chen 《Frontiers of Environmental Science & Engineering in China》2008,2(2):178-186
The background, concept, connotation, principles, and methods of eco-planning for an Eco-Demonstration Park (EDP) and sustainability
were examined based on a case study of the Luhua EDP in the Chongming Island of Shanghai, China, which is an important part
of Shanghai Eco-city planning and construction in the 21st century. By analyzing natural, social and economic conditions,
calculating population using the land capacity eco-model, eco-function zoning, and eco-construction, an innovative eco-industrial
structure and technical chain were formulated. A comprehensive eco-planning scheme for the EDP was proposed, including planning
and management strategies for subsystems of efficient industry, good quality human settlement, high standard eco-construction
and eco-tourism as well as effective environmental protection and attractive landscape. The EDP should be an area with coordinated
and sustainable economic, social and environmental subsystems. Eco-planning for the EDP should be a very important part of
eco-city planning and sustainability. The paper aims to set up a theoretical framework and practical basis for eco-planning
and promoting harmony between human and nature. 相似文献
8.
China has among the highest biodiversities in the world, but faces extreme biodiversity losses due to the country’s huge population and its recent explosive socioeconomic development. Despite huge efforts and investments by the government and Chinese society to conserve biodiversity, especially in recent decades, biodiversity losses may not have been reversed, and may even have been exacerbated by unintended consequences resulting from these projects. China’s centralized approach to biodiversity conservation, with limited local participation, creates an inflexible and inefficient approach because of conflicts between local communities and national administrators over the benefits. Although community-based conservation may be an imperfect approach, it is an essential component of a successful future national conservation plan. Biodiversity conservation should be considered from the perspective of systems engineering and a governance structure that combines centralization with community-level conservation. In this paper, we describe China’s complex challenge: how to manage interactions between humans and nature to find win–win solutions that can ensure long-term biodiversity conservation without sacrificing human concerns. 相似文献
9.
微塑料是目前环境领域备受瞩目的新兴污染物,其污染监测基础数据仍存在许多空白亟待填补。本研究选择典型城市湖泊岳阳南湖为研究区域,对其表层水体微塑料污染进行研究。本研究在14个遍布南湖各个区域的采样点采集表层水体样品,基于湿式消解和密度分离方法对样品进行处理,并采用体视显微镜和显微红外光谱仪进行鉴定,对该区域45 μm—5 mm范围的微塑料污染水平、分布特征、潜在来源及风险进行探讨。研究结果表明,南湖表层水体微塑料丰度在3050—7100 n·m−3之间,平均值为（4664±1742）n·m−3,其污染水平高于大多数自然湖泊,与武汉、长沙等城市湖泊相当; 南湖表层水体中的微塑料更容易集中于湖泊中央区域,微塑料在南湖表层水体中的分布呈现“中高边低”的特点;南湖中检测到的微塑料以纤维状为主,其化学成分主要为聚乙烯、聚酰胺和聚对苯二甲酸乙二醇脂。由此可知,居民日常生活、旅游业、渔业是南湖微塑料的潜在来源;南湖表层水体微塑料的分布受到水动力条件影响显著;同时,研究区域对于碎片和微球微塑料的管控措施较为有效,而纤维微塑料仍大量赋存于南湖之中,这种情况需要得到重视,微塑料污染防控措施在未来需要进一步完善。 相似文献
10.
Disharmony between society and environmental carrying capacity: a historical review, with an emphasis on China 总被引：4，自引：0，他引：4
Nature can survive without humans, but humans cannot survive without nature. Despite a clear understanding of this dependency, humans continue to exist in disharmony with nature, and our current environmental and human dilemmas reflect old problems with a long history. Societies have historically experienced many transitions from harmony between nature and society to a crisis of disharmony, followed by a subsequent transition from crisis to harmony. Such ecological crises arise when society no longer practices sustainable consumption of resources within the limits imposed by the environmental carrying capacity. Over the long term, the growth in human desires has always exceeded the growth in the environmental carrying capacity. Science, technology, and social institutions must all be improved to resolve the ecological crises that arise from this imbalance. This paper discusses how increasing understanding of the problem by the public and by decision makers is the key to minimizing the undesirable impacts of the coming bottleneck for sustainable development. Furthermore, we emphasize how this awareness must be translated into fundamental political and economic changes. 相似文献