首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Loess Plateau, an arid and semi-arid region in Northwest China, is well-known for its most serious soil erosion in terms of sediment yield each year. Soil erosion, which is intensified by agricultural activities, is the major factor influencing sustainable agriculture development in this region. It reduces productivity by removing nutrients and especially reducing water availability that is essential for crop production in the area. It also brings about off-site costs by demanding more efforts for maintenance of banks and dams along Yellow River through raising the riverbed with sediment. Climate is capricious and extreme weather conditions occur frequently, which impairs normal agricultural production with erosion and also decrease of water availability. Extensive way of farming still dominates on the Loess Plateau, which cannot produce satisfying economic results and needs to be improved or altered. Conventional agricultural production pattern needs to be reconsidered for husbandry has not been granted its due position. Agriculture is the backbone of economy. Poor agricultural production impedes economic development and vice versa, backward economy also influences the advancement of agriculture. Besides a large population, education status of farmers is another threshold that requires being resolved for a sustainable agriculture.Although conventional agriculture has been practiced there for more than 5000 years, now it cannot meet the demand for food and fiber by the increasing population and some of its farming practices are contributing to environmental degradation directly or indirectly and can sustain no longer. Agriculture on Loess Plateau needs to find its own way of sustainability. To work toward a sustainable agriculture, chances and challenges both indwell on Loess Plateau.  相似文献   

2.
Loess Plateau,an arid and semi-arid region in Northwest China,is well-known for its most serious soil erosion in terms of sediment yield each year.Soil erosion,which is intensified by agricultural activities,is the major factor influencing sustainable agriculture development in this region.It reduces productivity by removing nutrients and especially reducing water availability that is essential for crop production in the area.It also brings about off-site costs by demanding more efforts for maintenance of banks and dame along Yellow River through raising the riverbed with sediment.Climate is capricious and extreme weather conditions occur frequently,which impairs normal agricultural production with erosion and also decrease of water availability.Extensive way of farming still dominates on the Loess Plateau,which canot produce satisfying economic results and needs to be improved or altered.Conventional agricultural production pattern needs to be reconsidered for husbandry has not been granted its due position.Agriculture is the backbone of economy.Poor agricultural production impedes economic development and vice versa,backward economy also influences the advancement of agriculture.Besides a large population,education status of farmers is another threshold that requires being resolved for a sustainable agriculture.Although conventional agriculture has been practiced there for more than 5000years,now it cannot meet the demand for food and fiber by the increasing population and some of its farming practices are contributing to environmental degradation directly or indirectly and can sustain no longer.Agriculture on Loess Plateau needs to find its own way of sustainability.To work toward a sustainable agriculture,chances and challenges both indwell on Loess Plateau.  相似文献   

3.
During the last decade, Sustainability Reporting (SR) has been increasingly adopted by corporations worldwide. This is evidenced by the adoption of several guidelines, such as the ISO 14000 series, the Social Accountability 8000 standard, and the GRI Sustainability Guidelines. SR shows promise to help corporate leaders and their employees to contribute towards achieving sustainable societies. However, most of the guidelines and standards address sustainability issues through comparmentalisation, thereby, leading to the separation of the economic, environmental, and social dimensions. Due to these divisive approaches, holistic assessments of the effects of their efforts are seldom properly integrated into coporate decisions and procedures to make improvements for example through Cleaner Production, Worker Health and Safety, Consumer Safety, and reductions in the negative short and long-term Social and Environmental Impacts.This paper analyses SR reports from three companies with the help of Grounded Theory's constant comparative analysis. This analytical framework helped the authors to systematically assess the degree to which the companies addressed economic, ecological and social issues separately or in an integrated and inter-linked manner. From the inter-linkages found, a new category is proposed to be added to future SR. This new category can help corporate SR planners and researchers on sustainability reports to better understand how the company leaders understand their responsibilities with regard to SD. These inter-connectednesses are highly relevant in many short and long-term dimensions of supply chain management, global warming, ecological disruption and societal equity issues, especially with regard to the local, national and global energy issues of fuels and oils, the central themes of the conference at which this paper was originally presented. It also plays a key role in real, long-term changes towards Sustainability, where the time dimension plays a key role in human survival on Planet Earth.  相似文献   

4.
The proliferation of sustainability assessment principles, strategies, actions, and tools has created confusion about pathways forward for companies. It is unclear how existing approaches are complementary or distinct. How does a company assess current products and materials? How could designers create more sustainable products? What criteria, principles, approaches, and tools should be applied? Why? Is there a practical “road map” to guide product designers and product development managers in integrating sustainability issues into their decision-making processes?This article builds on previous frameworks for understanding the interconnections between various assessment principles, strategies, actions, and tools related to industrial ecology, human and labor rights, and corporate social responsibility [Waage S, Geiser K, Irwin F, Weissman A, Bertolucci M, Fisk P, et al. Fitting together the building blocks for sustainability: a revised model for integrating ecological, social, and financial factors into business decision-making. Journal of Cleaner Production 2005;13(12):1117–206; Robèrt K-H, Schmidt-Bleek B, Aloisi de Larderel J, Basile G, Jansen JL, Kuehr R, et al. Strategic sustainable development—selection, design and synergies of applied tools. Journal of Cleaner Production 2002;10(3):197–214; Robèrt K-H. Tools and concepts for sustainable development, how do they relate to a framework for sustainable development, and to each other? Journal of Cleaner Production 2000;8(3):243–54]. Expanding on past work, this piece suggests a “road map” for application by product designers and product development managers. A four-phase process is offered for integrating systems and sustainability perspectives into product design, manufacturing, and delivery decisions.  相似文献   

5.
选择合适的地下水质量评价方法是保证评价结果科学合理的关键。以典型西南岩溶区地苏地下河系为研究对象,运用水质指数法和模糊综合指数法对该地下河系具有代表性的采样点水质进行评价。结果表明:地苏地下河系水质总体较好,2种方法评价得到的水质劣于GB/T 14848—2017《地下水质量标准》Ⅲ类水质的点位分别占全部水样的21.43%和32.14%,主要超标指标为 NO 3 - ,其最高检出浓度是Ⅲ类水质限值的2.3倍,超标点位主要集中于人类活动较强烈的地苏乡。在28个点位中,2种方法评价结果一致的点位有15个,存在差异点位的评价结果仅相差一个水质级别。水质指数法能够满足水质类别划分及水质定量评价的要求,但是对于超标指标不同的水样可比性较差;模糊综合指数法可精确地反映指标实际浓度与水质分级界限的接近程度,量化了所有评价指标对地下水水质的影响权重,使结果更精确,但是计算比较复杂,可操作性较差,且不能识别主要超标指标,在量化所有参评指标时有可能掩盖对人体健康和生态环境威胁较大的指标的影响。因此在实际应用中,应根据监测数据和评价目的选择合适的评价方法,使评价结果既能反映水体的实际情况,又能满足管理需要。  相似文献   

6.
Sustainability impact assessment tools aim at optimising the development of policy measures. Here, we present an approach to designing policies for multifunctional land use with application to Europe and its regions. After the 35 environmental, social and economic impact issues of the European Impact Assessment Guidelines were reviewed on the basis of spatiotemporal indicators at both the top-down Europe-wide and bottom-up intra-regional resolution level, cluster analysis identified classes with specific sustainability characteristics and thus regions most likely facing similar sustainability problems. Sensitive region types such as post-industrial zones, mountains, coasts and islands were analysed separately. The results of the cluster analysis were tested against evidence-based information such as UNEP priorities and regional stakeholder evidence. Stakeholder evidence was specifically explored for the land use policy ‘bioenergy promotion’ in Lusatia, Germany. We concluded that these top-down and bottom-up spatiotemporal data classifications with cluster analysis represent useful ex-ante impact assessment tools and need to be supplemented by participatory assessments. This procedure with top-down and bottom-up data analysis, and also participatory evidence, provide a valuable three-step sustainability impact assessment approach in policy making.  相似文献   

7.
忻州市土地利用现状的环境敏感区分析   总被引:1,自引:2,他引:1       下载免费PDF全文
王瑾  钱新  洪坚平  钱瑜 《中国环境科学》2010,30(12):1702-1707
随着新一轮土地利用规划修编展开,针对忻州市土地利用存在的环境问题,利用调查资料和相关研究成果,有效管理土地利用空间向环境敏感地区伸展,减缓环境敏感地区的环境压力和生态胁迫,为市域土地利用方式和分区方案制定提供环境敏感性依据.从规划方案与面临的土地生态问题入手,划分生态环境、水源保护、污染影响、优质农田以及煤矿塌陷五类环境敏感区,并进行忻州市环境敏感地综合评价,明确其空间分布范围.研究结果表明,极高敏感、高敏感区占全市总面积的4%,较高敏感区和一般敏感区分别占10.5%和7.5%,低敏感区和非敏感区分别占40%和38%.通过分析规划土地利用功能分区方案与环境的协调性, 在土地利用规划过程中,提出土地利用方式和空间布局优化对策.  相似文献   

8.
This study presents a quantitative and ecological benefit evaluation of the Baiyangdian wetland in China between the years 2000 and 2006. Methods of EMERGY analysis were applied to illustrate the wetland ecosystem, to evaluate the economic and environmental inputs and consequent yields, and to assess the sustainability of the Baiyangdian wetland. The indicators for the integrated ecological and economic system, such as EMERGY yield ratio (EYR) (7.51), EMERGY investment ratio (EIR) (4.52), environmental loading ratio (ELR) (2.92), EMERGY exchange ratio (0.41), and EMERGY sustainable indicator (ESI) (2.57) were calculated, compared, analyzed, and discussed. The non-renewable investment in Baiyangdian was greater than renewable investment, leading to the unsustainable development of the system. High EYR indicated that the Baiyangdian integrated system had created huge profits for its people, while ELR and ESI revealed that human behavior has been a heavy burden on the environment, and countermeasures should be taken by the Chinese government to relieve and resolve these problems. Potential management methods were also proposed in this paper.  相似文献   

9.
近年来,我国海洋保护区生态环境监测工作逐年加强,监测技术标准稳步发展,监测能力建设逐步推进,已在海洋保护区监管工作中发挥了重要作用。当前一些发达国家在海洋生态环境监测方面更加注重监测的制度建设,在形式上已步入“天-空-海、水面-水体-海底”立体监测时代。我国应借鉴国外的先进经验,着力构建和完善“天空地一体化”海洋保护区生态环境监测体系,加快推进海洋保护区生态环境监测标准化进程,加强海洋保护区信息共享机制建设,为我国海洋保护区生态环境监测工作的开展及海洋保护区监管工作提供有力支撑。  相似文献   

10.
Efficiency and sustainability of grain production has now been an important issue in China. Aiming at analyzing such efficiency and sustainability in different parts of China, the grain production system of Jiangsu and Shaanxi Provinces was analyzed and compared by means of using emergy method in this study. The results showed that deterioration of emergy input structure (inorganic assistant emergy inputs increased drastically while organic ones decreased or increased little) affected the grain production system's efficiency and sustainability of both provinces, and the situation of Jiangsu Province is more serious than that of Shaanxi Province. According to the results of efficiency and sustainability analysis, this paper suggests that we should utilize environmental resources abstemiously and dramatically to reduce the assistant emergy input structure into the grain production system.  相似文献   

11.
On Peak Namjagbarwa (Tibet Plateau), Lushan Mountain (Province Jiangxi), Flower Mountain and Shangdianzi (Beijing, near Great Wall) aerosol samples have been collected by cascade samplers. For comparison aerosol samples from Beijing City, Pacific Ocean and South Pole also have been collected. Samples were analyzed with PIXE or XFA instruments. Factor analysis and enrichment factor calculation were performed to process the data.  相似文献   

12.
The sustainability performance of five potential UK biodiesel feedstocks is reviewed and their greenhouse gas performance investigated using the carbon and sustainability reporting methods of the UK Renewable Transport Fuel Obligation (RTFO). Of the feedstocks examined, and for which the RTFO supplies default carbon intensity values, only used cooking oil has guaranteed sustainability benefits. The other feedstocks have CO2e payback periods of 25–5503 years if grown on converted forest or grassland, yet the RTFO currently requires no guarantee that this conversion has not taken place and requires no avoidance of indirect effects. As currently designed, the RTFO risks substantial, adverse environmental effects.  相似文献   

13.
14.
IntroductionAsanewbranchofecologyandaninterdisciplinaryfield,theecologicalengineeringwasinitiallyformulatedintheearly1960s.Durin...  相似文献   

15.
The geochemistry of natural waters in the Changtang Nature Reserve,northern Tibet,can help us understand the geology of catchments,and provide additional insight in surface processes that influence water chemistry such as rock weathering on the Qinghai–Tibet Plateau.However,severe natural conditions are responsible for a lack of scientific data for this area.This study represents the first investigation of the chemical composition of surface waters and weathering effects in two lake basins in the reserve(Lake Dogaicoring Qiangco and Lake Longwei Co).The results indicate that total dissolved solids(TDS)in the two lakes are significantly higher than in other gauged lakes on the Qinghai–Tibet Plateau,reaching 20–40 g/L,and that TDS of the tectonic lake(Lake Dogaicoring Qiangco)is significantly higher than that of the barrier lake(Lake Longwei Co).Na+and Cl-are the dominant ions in the lake waters as well as in the glacier-fed lake inflows,with chemical compositions mainly affected by halite weathering.In contrast,ion contents of inflowing rivers fed by nearby runoff are lower and concentrations of dominant ions are not significant.Evaporite,silicate,and carbonate weathering has relatively equal effects on these rivers.Due to their limited scope,small streams near the lakes are less affected by carbonate than by silicate weathering.  相似文献   

16.
西部地区植被恢复重建中几个问题的思考   总被引:44,自引:2,他引:44  
以退耕还林还草为主体的西部地区植被恢复重建是一项复杂的生态-经济复合系统工程,必须以水热等气候因子所决定的植被生物地带性为科学依据,以国家调控下的区域间互补的市场经济机制为运作体系,必须在建立长期稳定的经济补偿机制的同时,建立长期稳定的政策和法律保障体系。为此,该文讨论了西部地区自然植被的地理格局、适度的退耕规模和退耕后的植被恢复重建、植被恢复工程的环境服务功能产出、生态产业与经济补偿机制、天然植被的保护和改良等科学问题,指出了退耕还林还草试点工程中所存在的一些错误认识和不良倾向。  相似文献   

17.
Arable land soils generally have lower organic carbon (C) levels than soils under native vegetation; increasing the C stocks through improved management is suggested as an effective means to sequester CO2 from the atmosphere. China's arable lands, accounting for 13% of the world's total, play an important role in soil C sequestration, but their potential to enhance C sequestration has not yet been quantitatively assessed. The C sequestration by agricultural soils is affected by many environmental factors (such as climate and soil conditions), biological processes (crop C fixation, decomposition and transformation), and crop and soil management (e.g. tillage and manure application). Estimation of the C sequestration potential requires the quantification of the combined effects of these factors and processes. In this study, we used a coupled remote sensing- and process-based ecosystem model to estimate the potential for C sequestration in agricultural soils of China and evaluated the sustainability of soil C uptake under different soil management options. The results show that practicing no-tillage on 50% of the arable lands and returning 50% of the crop residue to soils would lead to an annual soil C sequestration of 32.5 Tg C, which accounts for about 4% of China's current annual C emission. Soil C sequestration with improved soil management is highly time-dependent; the effect lasted for only 20–80 years. Generally, practicing no-tillage causes higher rate and longer sustainability of soil C sequestration than only increasing crop residue into soils. The potential for soil C sequestration varied greatly among different regions due to the differences in climate, soil conditions and crop productivity.  相似文献   

18.
沙尘天气会危害人体健康并直接影响城市运行,当沙尘天气发生后,针对其清除过程及动力学机制鲜有研究.本文利用北京地区地面观测资料、风廓线雷达数据、四维变分多普勒雷达分析系统(Variational Doppler Radar Analysis System,VDRAS)数据、气溶胶激光雷达监测资料等,对比分析了2018年3月27—28日明显浮尘和2021年3月15日强沙尘暴天气的沙尘清除过程,研究了不同大气环流背景下的沙尘减弱消散动力机制.结果表明,在3月27—28日偏东风天气背景下:(1)北京地区沙尘浓度垂直分布及变化与高空槽及偏东风的强度垂直分布有紧密关系;(2)浮尘天气中,偏东风在1~1.5 km之上随高度减弱形成上升气流,与短波槽耦合,将高浓度气溶胶向高空输送;而1 km以下偏东风向地面风速减小,有利于下沉运动,不利于气溶胶向高层扩散,造成中层浓度降低;(3)随着2.5 km以下偏东风加强至低空急流,并随高度增加,上升运动显著增大,高浓度气溶胶被抬至高层并向下游输送,配合气团更迭,完成浮尘清除.而在3月15日强沙尘暴过程中:(4)沙尘浓度垂直分布变化与上游传输及低层强下沉运动有关,...  相似文献   

19.
Arsenic contamination is of great environmental concern due to its toxic effects as a carcinogen. Knowledge of arsenic background concentrations is important for land application of wastes and for making remediation decisions. The soil clean-up target level for arsenic in Florida (0.8 and 3.7 mg kg−1 for residential and commercial areas, respectively) lies within the range of both background and analytical quantification limits. The objective of this study was to compare arsenic distribution in urban and non-urban areas of Florida. Approximately 440 urban and 448 non-urban Florida soil samples were compared. For urban areas, soil samples were collected from three land-use classes (residential, commercial and public land) in two cities, Gainesville and Miami. For the non-urban areas, samples were collected from relatively undisturbed non-inhabited areas. Arsenic concentrations varied greatly in Gainesville, ranging from 0.21 to approximately 660 mg kg−1 with a geometric mean (GM) of 0.40 mg kg−1, which were lower than Miami samples (ranging from 0.32 to 112 mg kg−1; GM=2.81 mg kg−1). Arsenic background concentrations in urban soils were significantly greater and showed greater variation than those from relatively undisturbed non-urban soils (GM=0.27 mg kg−1) in general.  相似文献   

20.
Arsenic contamination is of great environmental concern due to its toxic effects as a carcinogen. Knowledge of arsenic background concentrations is important for land application of wastes and for making remediation decisions. The soil clean-up target level for arsenic in Florida (0.8 and 3.7 mg kg−1 for residential and commercial areas, respectively) lies within the range of both background and analytical quantification limits. The objective of this study was to compare arsenic distribution in urban and non-urban areas of Florida. Approximately 440 urban and 448 non-urban Florida soil samples were compared. For urban areas, soil samples were collected from three land-use classes (residential, commercial and public land) in two cities, Gainesville and Miami. For the non-urban areas, samples were collected from relatively undisturbed non-inhabited areas. Arsenic concentrations varied greatly in Gainesville, ranging from 0.21 to approximately 660 mg kg−1 with a geometric mean (GM) of 0.40 mg kg−1, which were lower than Miami samples (ranging from 0.32 to 112 mg kg−1; GM=2.81 mg kg−1). Arsenic background concentrations in urban soils were significantly greater and showed greater variation than those from relatively undisturbed non-urban soils (GM=0.27 mg kg−1) in general.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号