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81.
Halting forest loss and achieving sustainable development in an equitable manner require state, non-state actors, and entire societies in the Global North and South to tackle deeply established patterns of inequality and power relations embedded in forest frontiers. Forest and climate governance in the Global South can provide an avenue for the transformational change needed—yet, does it? We analyse the politics and power in four cases of mitigation, adaptation, and development arenas. We use a political economy lens to explore the transformations taking place when climate policy meets specific forest frontiers in the Global South, where international, national and local institutions, interests, ideas, and information are at play. We argue that lasting and equitable outcomes will require a strong discursive shift within dominant institutions and among policy actors to redress policies that place responsibilities and burdens on local people in the Global South, while benefits from deforestation and maladaptation are taken elsewhere. What is missing is a shared transformational objective and priority to keep forests standing among all those involved from afar in the major forest frontiers in the tropics.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01602-1.  相似文献   
82.
Mercury contamination in Canada's Bay of Fundy is a priority concern because of elevated levels observed in fish, birds and wildlife. Salt marshes constitute an important part of the Bay's coastline and are potential stores of mercury for the region. We measured the amount of mercury accumulated over a 5-yr period from 1997 to 2002 in surface sediments of seven salt marshes along the New Brunswick coast of the Bay. The seven study sites extended from outer to inner Bay, spanning a gradient in tidal range (6-12 m) and sediment characteristics such as %LOI (4-29%) and sediment deposition rate (0.27-1.76 cm yr(-1)). In each study site, mercury was measured in low and high marsh areas. Sediment mercury concentrations ranged from 7 to 79 ng g(-1) and loading rates ranged from 0.1 to 1.1 mg m(-2). Total estimated 5-yr storage of mercury in salt marsh sediments of the Bay is 854+/-465 kg. We also compared sediment mercury loading to atmospheric inputs measured at a deposition monitoring station operating in New Brunswick from 1997 to 2002 and found that direct atmospheric deposition appears to be a minor input of mercury to these sediments. We are unaware of documentation of mercury loading in salt marshes on a bay-wide scale and over a constrained (5-yr) time period elsewhere.  相似文献   
83.
The "Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS)" is underway to determine if infants who are exposed to diesel engine exhaust particles are at an increased risk for atopy and atopic respiratory disorders, and to determine if this effect is magnified in a genetically at risk population. In support of this study, a methodology has been developed to allocate local traffic source contributions to ambient PM(2.5) in the Cincinnati airshed. As a first step towards this allocation, UNMIX was used to generate factors for ambient PM(2.5) at two sites near at interstate highway. Procedures adopted to collect, analyze and prepare the data sets to run UNMIX are described. The factors attributed to traffic sources were similar for the two sites. These factors were also similar to locally measured truck engine-exhaust enriched ambient profiles. The temporal variation of the factors was analyzed with clear differences observed between factors attributed to traffic sources and combustion-related regional secondary sources.  相似文献   
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86.
Column Flotation Deinking: State-of-the-art and opportunities   总被引:1,自引:0,他引:1  
Flotation is a critical process step for ink removal from recycled paper. Column flotation is a specific form of flotation that has grown in popularity recently. Extensive efforts during the past four decades to improve the flotation deinking operation sought an optimum blend of technological parameters, physico-chemical aspects and economical process conditions. With increasing demand to recover and recycle waste paper due to ecological and economical concerns, there is a need for an improved process and therefore for in-depth understanding of the mechanism and fundamental factors involved in the efficiency and economics of the deinking process. This paper reviews the progress made in the last decade (2000–2010) in deinking hydrodynamics, various measurement techniques, scale-up and design criterion.  相似文献   
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88.
Globally, 6.4 million tons of fishing gear are lost in the oceans annually. This gear (i.e., ghost nets), whether accidently lost, abandoned, or deliberately discarded, threatens marine wildlife as it drifts with prevailing currents and continues to entangle marine organisms indiscriminately. Northern Australia has some of the highest densities of ghost nets in the world, with up to 3 tons washing ashore per kilometer of shoreline annually. This region supports globally significant populations of internationally threatened marine fauna, including 6 of the 7 extant marine turtles. We examined the threat ghost nets pose to marine turtles and assessed whether nets associated with particular fisheries are linked with turtle entanglement by analyzing the capture rates of turtles and potential source fisheries from nearly 9000 nets found on Australia's northern coast. Nets with relatively larger mesh and smaller twine sizes (e.g., pelagic drift nets) had the highest probability of entanglement for marine turtles. Net size was important; larger nets appeared to attract turtles, which further increased their catch rates. Our results point to issues with trawl and drift‐net fisheries, the former due to the large number of nets and fragments found and the latter due to the very high catch rates resulting from the net design. Catch rates for fine‐mesh gill nets can reach as high as 4 turtles/100 m of net length. We estimated that the total number of turtles caught by the 8690 ghost nets we sampled was between 4866 and 14,600, assuming nets drift for 1 year. Ghost nets continue to accumulate on Australia's northern shore due to both legal and illegal fishing; over 13,000 nets have been removed since 2005. This is an important and ongoing transboundary threat to biodiversity in the region that requires attention from the countries surrounding the Arafura and Timor Seas. Entender las Fuentes y Efectos de Equipo de Pesca Abandonado, Perdido y Desechado sobre las Tortugas Marinas del Atlántico Norte  相似文献   
89.
Abstract

Nowadays, the heating, ventilation, and air conditioning (HVAC) system has been an important facility for maintaining indoor air quality. However, the primary function of typical HVAC systems is to control the temperature and humidity of the supply air. Most indoor air pollutants, such as volatile organic compounds (VOCs), cannot be removed by typical HVAC systems. Thus, some air handling units for removing VOCs should be added in typical HVAC systems. Among all of the air cleaning techniques used to remove indoor VOCs, photocatalytic oxidation is an attractive alternative technique for indoor air purification and deodorization. The objective of this research is to investigate the VOC removal efficiency of the photocatalytic filter in a HVAC system. Toluene and formaldehyde were chosen as the target pollutants. The experiments were conducted in a stainless steel chamber equipped with a simplified HVAC system. A mechanical filter coated with Degussa P25 titania photocatalyst and two commercial photocatalytic filters were used as the photo-catalytic filters in this simplified HVAC system. The total air change rates were controlled at 0.5, 0.75, 1, 1.25, and 1.5 hr?1, and the relative humidity (RH) was controlled at 30%, 50%, and 70%. The ultraviolet lamp used was a 4-W, ultraviolet-C (central wavelength at 254 nm) strip light bulb. The first-order decay constant of toluene and form-aldehyde found in this study ranged from 0.381 to 1.01 hr?1 under different total air change rates, from 0.34 to 0.433 hr?1 under different RH, and from 0.381 to 0.433 hr?1 for different photocatalytic filters.  相似文献   
90.
Scleractinian corals experience a wide range of flow regimes which, coupled with colony morphology, can affect the ability of corals to capture zooplankton and other particulate materials. We used a field enclosure oriented parallel to prevailing oscillatory flow on the forereef at Discovery Bay, Jamaica, to investigate rates of zooplankton capture by corals of varying morphology and polyp size under realistic flow speeds. Experiments were carried out from 1989 to 1992. Particles (Artemia salina cysts) and naturally occurring zooplankton attracted into the enclosures were used as prey for the corals Madracis mirabilis (Duchassaing and Michelotti) (narrow branches, small polyps), Montastrea cavernosa (Linnaeus) (mounding, large polyps), and Porites porites (Pallas) (wide branches, small polyps). This design allowed corals to be used without removing them or their prey from the reef environment, and avoided contact of zooplankton with net surfaces. Flow speed had significant effects on capture rate for cysts (M. mirabilis), total zooplankton (M. mirabilis, M. cavernosa), and non-copepod zooplankton (M. mirabilis). Zooplankton prey capture increased with prey concentration for M. mirabilis and M. cavernosa, over a broad range of concentrations, indicating that saturation of the feeding response had not occurred until prey density was over 104 items m−3, a concentration at least an order of magnitude greater than the normal range of reef zooplankton concentrations. Location of cyst capture on coral surfaces was not uniform; for M. cavernosa, sides and tops of mounds captured most particles, and for P. porites, capture was greatest near branch tops, but was close to uniform for M. mirabilis branches in all flow conditions. The present study confirms laboratory flume results, and field results for other species, suggesting that many coral species experience particle flux and encounter rate limitations at low flow speeds, decreasing potential zooplankton capture rates. Received: 17 September 1996 / Accepted: 22 November 1997  相似文献   
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