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551.
The post-Rio environmental accord has offered new opportunities for landscape planning linking global concerns with Local Agenda 21 through concepts of sustainable development. This paper analyses the potential for integrated landscape planning by linking the aims of global sustainability with a major initiative of the UK Government, the National Forest located in the English Midlands. A common commitment to concepts of partnership and participation facilitated by local authorities can be found in the National Forest Strategy and in the principles of Local Agenda 21. Using case studies comparing local fora created to implement parts of the National Forest Strategy with focus groups formed to prepare Local Agenda 21 Action Plans, it is argued that a common consensus between these endeavours has not so far been achieved. Problems associated with the interpretation of national government policy guidance following the Earth Summit coupled with the constitution, membership and goals of specific groups are viewed as the primary reasons for conflict. These have implications for achieving compatibility between the Forest ideals and those enshrined in Local Agenda 21, particularly in localities where mineral exploitation and landfill are contentious planning concerns. 相似文献
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Rosalind Aughwane Emma Ingram Edward D. Johnstone Laurent J. Salomon Anna L. David Andrew Melbourne 《黑龙江环境通报》2020,40(1):38-48
Objective
Magnetic resonance imaging (MRI) of placental invasion has been part of clinical practice for many years. The possibility of being better able to assess placental vascularization and function using MRI has multiple potential applications. This review summarises up-to-date research on placental function using different MRI modalities.Method
We discuss how combinations of these MRI techniques have much to contribute to fetal conditions amenable for therapy such as singletons at high risk for fetal growth restriction (FGR) and monochorionic twin pregnancies for planning surgery and counselling for selective growth restriction and transfusion conditions.Results
The whole placenta can easily be visualized on MRI, with a clear boundary against the amniotic fluid, and a less clear placental-uterine boundary. Contrasts such as diffusion weighted imaging, relaxometry, blood oxygenation level dependent MRI and flow and metabolite measurement by dynamic contrast enhanced MRI, arterial spin labeling, or spectroscopic techniques are contributing to our wider understanding of placental function.Conclusion
The future of placental MRI is exciting, with the increasing availability of multiple contrasts and new models that will boost the capability of MRI to measure oxygen saturation and placental exchange, enabling examination of placental function in complicated pregnancies. 相似文献556.
Costas A. Velis David C. Wilson Christopher R. Cheeseman 《Waste management (New York, N.Y.)》2009,29(4):1282-1290
The material recovery methods used by dust-yards in early 19th century London, England and the conditions that led to their development, success and decline are reported. The overall system developed in response to the market value of constituents of municipal waste, and particularly the high coal ash content of household ‘dust’. The emergence of lucrative markets for ‘soil’ and ‘breeze’ products encouraged dust-contractors to recover effectively 100% of the residual wastes remaining after readily saleable items and materials had been removed by the thriving informal sector. Contracting dust collection to the private sector allowed parishes to keep the streets relatively clean, without the need to develop institutional capacity, and for a period this also generated useful income. The dust-yard system is, therefore, an early example of organised, municipal-wide solid waste management, and also of public–private sector participation. The dust-yard system had been working successfully for more than 50 years before the Public Health Acts of 1848 and 1875, and was thus important in facilitating a relatively smooth transition to an institutionalised, municipally-run solid waste management system in England. The dust-yards can be seen as early precursors of modern materials recycling facilities (MRFs) and mechanical–biological treatment (MBT) plants; however, it must be emphasised that dust-yards operated without any of the environmental and occupational health considerations that are indispensable today. In addition, there are analogies between dust-yards and informal sector recycling systems currently operating in many developing countries. 相似文献
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This article discusses some of the demonstrated and potential uses of data from satellites with large fields of view and high frequency of coverage, such as NOAA AVHRR data and Nimbus-7 CZCS data. The use of such data is discussed for three types of applications: (a) stratification, (b) change detection, and (c) area estimation. It is concluded that such data have considerable promise as an aid to a variety of large-area inventory and monitoring tasks. 相似文献
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At a fixed Cd2+ concentration water hyacinth () plants with greater root mass (dry weight) take up more metal ions as a function of time, and more metal ions are taken up by a plant as the solution volume is increased. Experiments in which several different metal ion complexers were present suggest that (1) the roots possess sites which initially reversibly bind free Cd2+, (2) some added complexers can compete with these root sites for free Cd2+, and (3) with time Cd2+ bound to the roots is translocated into into the root tissues effectively removing it from the equilibrium processes in solution. Many metal ions are taken up by the plant but only the micronutrient Zn2+ competes well with Cd2+ for uptake. Thus, there may be binding sites on the roots for specific metal ions. 相似文献
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