天津市农村可再生能源管理障碍分析与政策选择

开展天津市农村可再生能源管理障碍分析与政策研究,可为全市加强农村可再生能源管理、保护和改善农村生态环境提供参考。文章阐述了天津市农村可再生能源管理的基本架构,结合生态文明、能源安全、依法治国等战略形势强调了全市农村可再生能源管理面临的挑战,从思想认识、管理体制、法规政策、宏观规划、后续管理等多个维度全面分析了存在的管理障碍,并针对性地提出了相关政策建议。研究认为,全市加强农村可再生能源管理必须优化政策路径,进一步健全管理体制机制、完善法律政策体系、加强科学规划、完善市场机制、强化后续监管服务、健全宣传教育体系等。     

Comparative assessment of stream acidity using diatoms and macroinvertebrates: implications for river management and conservation

• 1. Macroinvertebrates and phytobenthic organisms (e.g. diatoms) are frequently used as bioindicators of water quality, yet few studies compare their effectiveness despite both being emphasized in the EC Water Framework Directive.
• 2. Here, as a case study, the efficacy of each group in assessing acid–base status in the catchment of the Welsh River Wye was evaluated from surveys in 2 years.
• 3. Ordination showed that both diatom and macroinvertebrate assemblages varied highly significantly with pH, alkalinity and calcium concentrations. Moreover, ordination scores were highly inter‐correlated between these groups in both study years.
• 4. There were also contrasts, with diatoms and macroinvertebrates changing in differing ways with catchment land‐use and channel hydromorphology. These differing responses suggest complementary indicator value, while variation in generation times between diatoms and macroinvertebrates suggests potentially contrasting speeds of response to variations over different timescales.
• 5. These data reveal that significant water quality problems in the River Wye, a proposed Special Area of Conservation, are generated from the continued acidification of low‐order, headwater streams and this has considerable significance for the objectives of the Water Framework Directive, and the EC Habitats Directive.

Copyright © 2006 John Wiley & Sons, Ltd.     

Notes on coastal lagoon typology in the light of the EU Water Framework Directive: Italy as a case study

• 1. The European Water Framework Directive (WFD) requires that Member States differentiate the transitional water bodies into types.
• 2. WFD assigns coastal lagoons to two different water categories, ‘transitional waters’ and ‘coastal waters’ on the basis of freshwater influence.
• 3. The main physical factors that contribute to the genesis and characterization of coastal lagoons are coastal typology, tidal range and climate.
• 4. Italian lagoons are presented as an example of how these physical factors can be used in coastal lagoon characterization and typology. On this basis, a clear distinction of Italian lagoons into two main groups is possible: Northern Adriatic and Mediterranean.
• 5. Large lagoons can be profitably subdivided into a hierarchical system of sub‐basins facilitating both the comparison of parts of the same lagoon and the comparison between different lagoons.
• 6. The basins are consistent water bodies that can be used as managerial units for environmental conservation, species protection and wise use of resources.

Copyright © 2006 John Wiley & Sons, Ltd.     

Assessment of the ecological status of north‐eastern Adriatic coastal waters (Istria,Croatia) using macroalgal assemblages for the European Union Water Framework Directive

• 1. Based on the inclusion of macroalgae in the European Union Water Framework Directive as quality elements for the evaluation of the ecological status of coastal waters, the suitability of one (Ecological Evaluation Index, EEI) of several previously proposed evaluation methods in the particular ecological conditions of the northern Adriatic Sea was tested.
• 2. The EEI was assessed for 10 locations (polluted and putatively pristine) scattered along 60 km of the western Istrian coast. The sampling was performed seasonally at 1 and 3 m depth by destructive (determination of species cover and biomass) and non‐destructive (determination of species coverage using digital photography) methods.
• 3. When assessed at 1 m depth the spatial scale weighted EEI for the west Istrian coast was 8.1, corresponding to an ecological status class (ESC) value of high. However, data for 3 m depth gave a spatial EEI of 6.72 which corresponds to an ESC value of good. Regressions of the ratio of ecological state group I (ESG I, i.e. thick leathery, calcareous and crustose species) over total algal abundance with the pollution gradient (obtained using principal components analysis (PCA) ordination of environmental variables) were significant at 3 m but not at 1 m depth. This was due to the high abundance of ESG I macroalgae Corallina elongata and Cystoseira compressa at 1 m depth at polluted stations. Similar regressions were obtained using cover, biomass and coverage.
• 4. It is concluded that the EEI method may be suitable for the classification of coastal waters in the northern Adriatic only in certain cases. A better assessment of ecological status using this method would require more realistic estimations based on the inclusion of data from several sampling depths. As all three abundance measures (cover, biomass, coverage) gave similar results, coverage (using digital photography) is suggested as being a preferred measure owing to the rapidity of sampling at several depths and less time‐consuming laboratory work.

Copyright © 2008 John Wiley & Sons, Ltd.     

Historical distribution of freshwater fishes and the reference conditions concept in a large Mediterranean basin

1. The European Water Framework Directive 2000/60/EC (WFD) defines the ecological status of aquatic systems as the deviation between their present biological state and that which would be expected in the absence of any major human disturbance, referred to by the WFD as the ‘reference condition’ (RC). It assumes that their biotic composition should remain balanced and constant over time. This study tested both assumptions against an analysis of the historical distribution of the fish fauna in a large and highly disturbed Mediterranean basin. If fish communities change substantially over time, it will mean that the validity of the RC concept comes into question.
2. Using presence/absence data for historical native fish fauna from the Guadalquivir Basin, distribution changes among sub-basins were quantified by mapping between the nineteenth century and today.
3. The range of two native species (Anguilla anguilla and Salmo trutta) has changed significantly. In addition, the diadromous species assemblage has almost become locally extinct, with the exception of the eel. Finally, most Guadalquivir sub-basins (94.7%) have suffered major changes in the composition of their fish communities, either by losing native species or by adding new non-native species.
4. These results render the definition of any RC unlikely. In Mediterranean areas, the WFD objective of ‘good ecological status’ recovery based on the integrity of aquatic communities is a theoretical rather than a real goal. Nonetheless, the WFD provides an ecological guiding principle that can also be transferred to the conservation of freshwater ecosystems.
5. As an alternative to the RC concept in Mediterranean lotic ecosystems, specific multimetric indices can be used, based on expert criteria, the metrics of which can also relate to the conservation value of water bodies, and not only to their ecological status.

     

SOIL QUALITY AND SPATIAL VARIABILITY ASSESSMENT OF LAND USE EFFECTS IN A TYPIC HAPLUSTOLL

Soil management practices can have negative or positive effects on soil quality. Our objective was to assess the effect of long‐term agricultural practices by evaluating selected soil physical and chemical properties. Soil samples were collected from two depths (0 to 15 and 15 to 30 cm) within a native pasture and an adjacent agricultural field that was being used for three different crop rotations. Soil quality was quantified using aggregate stability, bulk density, soil texture and available water content as physical properties and pH, electrical conductivity, organic matter and available phosphorus as chemical properties. The farmland soils were functioning at 71 and 70 per cent of their full potential at the 0‐ to 15‐ and 15 to 30‐cm‐depth increments, respectively, whereas those from the pasture were functioning at 73 and 69 per cent, respectively. The assessment showed substantial loss in soil organic carbon following 50 years of farmland cultivation. Tillage and fertilizer applications were presumably the primary reasons for weaker spatial dependence within farmland at the 0‐ to 15‐cm depth. Grazing was postulated as the main reason for weaker spatial dependence within the pasture soils at the 15‐ to 30‐cm depth. Overall, we conclude that 50 years of cultivation has not caused soil quality to decline to a point that threatens sustainability of the agricultural fields. Copyright © 2011 John Wiley & Sons, Ltd.     

Fish‐based assessment of ecological status of Finnish lakes loaded by diffuse nutrient pollution from agriculture

Abstract The European Union Water Framework Directive stipulates that pressures on surface waters due to diffuse loading of nutrients have to be taken into account in determination of their ecological status. A Finnish data set of fish communities in 178 lakes was used to assess the effects of agriculture‐induced nutrient loads on the ecological status of lakes. The lakes were divided to reference (n = 100) and impacted sites (n = 78) based on water quality, land use and nutrient load data. Fish sampling was conducted by standardised gill net test fishing. A fish‐based classification tool of the four parameters (EQR4) was applied to assess the ecological status of lakes. The parameters included were: mean total biomass of fish per gill net night, number of fish individuals per gill net night, biomass proportion of cyprinid fishes and the presence of indicator species. The analysis resulted in a median EQR4 value of 0.78 (good status) for reference lakes and 0.56 (moderate status) for affected lakes. Thus, the classification tool gave an acceptable output for different nutrient‐loaded lakes.     

基于海峡两岸经济合作框架协议的两岸渔业经济合作

归纳总结了《海峡两岸经济合作框架协议》(ECFA)和几个附件的内容,分析了ECFA生效之后,货物贸易早期收获产品清单对渔业动物产品进口的影响。研究认为,从台湾进口水产动物产品税率的降低和趋于零,无疑将大大提升台湾水产动物产品在大陆的竞争力;早期收获计划实施后,台湾出口到大陆的水产动物产品数量将会大幅度提高。这种状况无疑是对大陆水产企业的一种挑战和冲击。只有在不断提高产品质量和安全、不断降低生产成本的情况下,大陆的水产企业才能应对这种挑战,承受这种冲击。在服务贸易方面,如果台湾能够在大陆设立这些方面的企业,提供有关远洋渔业、水产养殖和水产品加工方面的科学研究和开发服务,必将推动我国大陆渔业技术的快速提升,促进渔业经济的健康、快速发展。在投资与经济合作方面,如果在ECFA的框架下,逐步减小双方投资的限制,从目前的侧重第一、第二产业的投资扩展到全方位的投资,涵盖水产苗种繁育、水产品加工、水产饲料、远洋渔业、休闲渔业、科技合作等领域,则必定促进大陆水产产业的整体提升,提高渔业经济的效益。作者对在ECFA框架下的渔业经济合作,从渔业资源养护与管理、休闲渔业等几个方面提出了建议。     

基于系统动力学的生态工业系统模型构建——以南通经济技术开发区为例

以南通经济技术开发区为研究层面,利用系统动力学方法的反馈作用机制,构建以经济产出、物质消耗、污染排放、综合集成为子系统的系统动力学模型。模型应用Vensim-DSS软件,模拟2002年后生态化发展情景,历史模拟值与实际值拟合较好,模型具有较强的应用性。结果说明开发区系统输入输出增长趋势速度减缓;系统生态效率持续增加,但污染排放指数增幅最大,环境压力很大。通过微调决策变量仿真发展情景,决策者可选择提高系统效率的综合管理情景。