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Concerns over water scarcity, climate change, and environmental health risks have prompted some Asian cities to invest in river rehabilitation, but deciding on the end goals of rehabilitation is a complex undertaking. We propose a multidisciplinary framework linking riparian landscape change to human well‐being, providing information relevant to decision makers, in a format that facilitates stakeholder involvement. We illustrate this through a case study of the densely settled, environmentally degraded, and flood prone Ciliwung River flowing through metropolitan Jakarta, Indonesia. Our methodology attempts to respond to this complexity through an iterative approach, strongly based on conceptualization and mathematical modeling. Nested hydrologic, hydrodynamic, and water quality models provide outputs at catchment‐, corridor‐, and localized site‐scales. Advanced 3‐D landscape modeling is used for procedural design and precise visualization of proposed changes and their impacts, as predicted by the mathematical models. Finally, participatory planning and design methods allow us to obtain critical stakeholder feedback in shaping a socially acceptable approach. Our framework aims at demonstrating that a change in paradigm in river rehabilitation is possible, and providing future scenarios that balance concerns over flooding, water quality, and ecology, with the realities of a rapidly growing megacity.  相似文献   
43.
We describe successful prenatal diagnosis in four pregnancies at risk for non-ketotic hyperglycinemia, two affected and two unaffected, using the glycine level and the glycine/ serine ratio in amniotic fluid obtained at 16 weeks gestational age. Although this method of prenatal diagnosis for non-ketotic hyperglycinemia has been effective in our hands the narrow differences between affected and unaffected pregnancies indicate the need for caution concerning its reliability.  相似文献   
44.
To understand contaminant transport in aquatic systems, it is essential to define the physical characteristics of the primary particulate carriers. The distribution of organic pollutants with particle-size class and particle morphology in a freshwater embayment (Hamilton Harbor, western Lake Ontario) was studied using a sequence of novel sample preparation and characterization techniques. Water samples (24 L) were fractionated according to particle-size distribution using differential cascade sedimentation and centrifugation methods. These size fractions were subsequently subjected to a physicochemical characterization using scanning transmission electron microscopy and energy-dispersive spectroscopy to identify flocs and individual colloidal particles in the size range of 1 nm to 1 mm in diameter. Analytical chemical analyses were performed to identify organic contaminants in extracts prepared from particle-size classes, including polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). The contaminant distribution trends were very similar for all compound classes studied; contaminants were primarily associated with fractions containing particles less than 2 mum in diameter. Morphological characterization of these fractions showed the majority of the particulates to be humic fractals. The results of this study show that contaminants in aquatic systems can be preferentially associated with specific types of particle carriers, the characteristics of which can be clearly defined in terms of size and morphology.  相似文献   
45.
ABSTRACT

Forest frontiers worldwide reveal trade-offs that are key in mitigating global change. In the forest frontiers of northeast Madagascar, land-use changes result from decisions made by smallholder farmers. In the past, subsistence needs led to increasing shifting cultivation, resulting in forest degradation and deforestation. This study focuses on investigating the role of locally determined factors in land-use change decisions in the forest frontier context. Therefore, we developed a Bayesian network-based land-use decision model that represents the causalities between factors influencing land-use decisions and takes into account local decision-makers’ knowledge. The approach is applied in two comparative case studies in northeast Madagascar. Results show that farmers mostly aim at extending the cultivation of cash crops. These results and the causal mechanisms disentangled for the forest frontier of northeast Madagascar help understand change mechanisms and hence, support decision-making to attain the Sustainable Development Goals.  相似文献   
46.
Factors concerning NO2 uptake by the absorbent triethanolamine (TEA) in NO2 diffusion tubes are examined. Although the nominal freezing point of TEA is 17.9-21.2 degrees C, we show that, for a range of aqueous TEA solutions (0-20%, H2O), no freezing occurs even at -10 degrees C. Therefore NO2 collection efficiency is unlikely to be impaired by low temperature exposure. The recovery of TEA from the meshes of exposed samplers is determined as approximately 98%, even after 42 days, showing that the stability in situ of TEA is unaffected by long-term exposure. A model of a diffusion tube sampling array for simultaneous exposures, with a 0.1 m sampler spacing, shows that NO2 uptake by individual samplers is not affected by the presence of neighbouring tubes in the array. This is confirmed by sampler precision at two Cambridge sites. Four sampler preparation methods are compared for differences in NO2 uptake of exposed samplers. All methods employ TEA as absorbent, transferred by either dipping meshes in a TEA-acetone solution or pipetting aliquots of a TEA-H2O solution onto the meshes. For samplers prepared by three of the methods, no difference in NO2 uptake is found, but for samplers prepared using a 50% v/v TEA-H2O solution, a mean reduction of 18% is found. Student's t-tests show that the difference is highly significant (P < or = 0.001). Reasons for the difference are discussed.  相似文献   
47.
Regional Environmental Change - Ecosystem services (ES) management has to cope with a high degree of uncertainty related to changes in socio-economic and climatic conditions as well as in societal...  相似文献   
48.
Mountain landscapes are undergoing rapid land-use changes. Settlement expansion, the intensification of agricultural land-use practices, and farmland abandonment result in a decline of natural and semi-natural habitats and the related ecosystem services (ES). In this context, spatial planning has emerged as a key instrument for the management of ES provision. To better understand trade-offs and interactions between settlement growth and ES provision in a spatially explicit manner, we present a new modeling framework coupling an agent-based, agro-economic optimization model and a cellular-automata-based settlement growth model. The framework is applied in an inner alpine valley in the Valais, Switzerland, which experienced rapid settlement growth in recent years. Results demonstrate how the model framework allows support of local planning processes. Particularly cooperation among municipalities and an explicit consideration of ES can inform spatially explicit ES trade-off decisions under increasing demand for land. We conclude that better informed spatial planning processes support ES provision.  相似文献   
49.
Irshad H  Mumtaz Z  Levay A 《Disasters》2012,36(3):452-464
This study documents the long-term gendered impact of the 2005 Pakistan earthquake on women and men who were rendered paraplegic as a result of spinal cord injuries sustained during the disaster. Coping mechanisms are also mapped. The findings show that three years after the disaster, paraplegic women are socially, emotionally, and financially isolated. The small stipend they receive is a significant source of income, but it has also led to marital distrust, violence, and abuse. In contrast, men receive full social and emotional support. Their key concern is that the government is not providing them with opportunities to be economically productive. Contemporary discourse and post-disaster policies, while acknowledging the importance of incorporating a gender perspective in the immediate post-disaster period, have failed to acknowledge and address the longer-term gendered impact of disasters, in terms of the different types of impact and strategies adopted by women and men.  相似文献   
50.
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