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191.
192.
The Green Climate Fund (GCF) is a significant and potentially innovative addition to UNFCCC frameworks for mobilizing increased finance for climate change mitigation and adaptation. Yet the GCF faces challenges of operationalization not only as a relatively new international fund but also as a result of US President Trump’s announcement that the United States would withdraw from the Paris Agreement. Consequently the GCF faces a major reduction in actual funding contributions and also governance challenges at the levels of its Board and the UNFCCC Conference of the Parties (COP), to which it is ultimately accountable. This article analyzes these challenges with reference to the GCF’s internal regulations and its agreements with third parties to demonstrate how exploiting design features of the GCF could strengthen its resilience in the face of such challenges. These features include linkages with UNFCCC constituted bodies, particularly the Technology Mechanism, and enhanced engagement with non-Party stakeholders, especially through its Private Sector Facility. The article posits that deepening GCF interlinkages would increase both the coherence of climate finance governance and the GCF’s ability to contribute to ambitious climate action in uncertain times.

Key policy insights

  • The Trump Administration’s purported withdrawal from the Paris Agreement creates challenges for the GCF operating model in three key domains: capitalization, governance and guidance.

  • Two emerging innovations could prove crucial in GCF resilience to fulfil its role in Paris Agreement implementation: (1) interlinkages with other UNFCCC bodies, especially the Technology Mechanism; and (2) engagement with non-Party stakeholders, especially private sector actors such as large US investors and financiers.

  • There is also an emerging soft role for the GCF as interlocutor between policy-makers and non-Party actors to help bridge the communication divide that often plagues cross-sectoral interactions.

  • This role could develop through: (a) the GCF tripartite interface between the Private Sector Facility, Accredited Entities and National Designated Authorities; and (b) strengthened collaborations between the UNFCCC Technical and Financial Mechanisms.

  相似文献   
193.
Landslides - A World Tsunami Awareness Day Special Event was held in hybrid mode on 5 November 2021, during the Fifth World Landslide Forum, in Kyoto, Japan. In this context, a panel discussion was...  相似文献   
194.
195.
Swimming with humpback whales in the Kingdom of Tonga is a growing industry that provides important revenue for a small Pacific Island economy. However the sustainability of this industry has been questioned due to its potential impact on the animals involved. The activity focuses on an ‘endangered’ subpopulation of humpback whales, with swimming occurring in the breeding area primarily with groups of animals containing young calves. This paper examines the relationship between the existing Tongan Government draft regulations and Tonga Whale Watching Operator Association guidelines that control the industry and visitor expectations about the management of the activity. There is significant support from visitors for strong, easy to understand and enforceable regulations governing the swim with whales industry. There is a clear correlation between current moves to strengthen Government regulations and the expectation from visitors that their activity is, and will be, conducted in a sustainable manner. The study recommends that to ensure compliance with regulations, appropriate management fees should be charged, visitors should be engaged in environmental education activities and further research should be conducted on the impacts of swimming with humpback whales.  相似文献   
196.
We estimate the unregulated catch and fisher income of the Kabui Bay migrant anchovy fishery operating in the Raja Ampat regency, Papua, Indonesia. Interviews with migrant fishers were conducted in April and November 2006, and estimates were generated through Monte Carlo simulations. Anchovy fisher income averaged US $1835 per year, about twice the average fisher income in the area. The income levels estimated by this study suggests that there is potential for the Raja Ampat Fisheries Bureau to capture some economic rent from the fishery to help fund a fisheries management program, from which Raja Ampat could benefit.  相似文献   
197.
Radium isotopes (223Ra, 224Ra, 226Ra, and 228Ra) and water chemistry were used to identify two chemically distinct sources of submarine groundwater discharge (SGD) in Celestún Lagoon, Yucatán, Mexico. Low salinity groundwater discharging from springs within the lagoon has previously been identified and extensively sampled for nutrient concentrations. However, a second type of groundwater discharging into the lagoon was detected during this study using radium isotope activity measurements. This second type of groundwater is characterized by moderate salinities (within the range of lagoon salinities) and very elevated radium activities in comparison to the low salinity groundwater, mixed lagoon water, and seawater. Further analysis showed that the two types of groundwater also have distinct chloride, strontium, and sulfate ratios, along with slightly different nutrient concentrations. Groundwater discharge occurs through large and small springs scattered throughout the lagoon, and both types of groundwater were detected discharging from one of the larger springs. The relative proportions of low salinity groundwater and brackish high radium groundwater varied over the tidal cycle. In order to better understand the relative contributions of each type of groundwater to the lagoon, a three end-member mixing model based on the distinct chemical and isotopic compositions of both types of groundwater and of seawater was used to estimate the distribution of each water type throughout the lagoon in different seasons. This study suggests that substantial groundwater discharge to the lagoon can occur during both dry and rainy seasons. The presence of two groundwater sources has implications for monitoring and protection of the Celestún Lagoon Biosphere Reserve, since the two sources may have different susceptibilities to anthropogenic contamination depending on their respective recharge area and recharge rates.  相似文献   
198.

Gold production in South Africa is projected to continue its decline in future, and prospects for discovery of new high-grade deposits are limited. Many of the mining companies have resorted to mining and processing low-grade and complex gold ores. Such ores are technically challenging to process, which results in low recovery rates, excessive reagent consumption and high operating costs when compared to free-milling gold ores. In the Witwatersrand mines, options of blending low-grade gold ores with high-grade ores exist. Although it is well known that most of the Witwatersrand gold ores are highly amenable to gold cyanidation, not much is known on the leachability of blended ores, especially the effects of mineralogical and metallurgical variability between different gold ores. In this study, we apply a geometallurgical approach to investigate mineralogical and metallurgical factors that influence the leaching of blended ores in a set of bottle shaker and reactor column tests. Three gold-bearing conglomerate units, so-called reefs, i.e., Carbon Leader Reef, Ventersdorp Contact Reef and the Black Reef, all in the Carletonville goldfield, were sampled. The ores were prepared using a terminator jaw crusher followed by vertical spindle pulverizer (20 kg aliquot) and high-pressure grinding rolls (80 kg aliquot). Mineralogical analysis was conducted using a range of complementary tools such as optical microscopy, QEMSCAN and micro–XCT. The results show that Witwatersrand gold ores are amenable to the process of ore blending. Some of the ores, however, contain impervious inert gangue and reactive ore minerals. Leach solution can only access gold locked in impervious gangue minerals through HPGR-induced pores and/or cracks. The optimum ore blending ratio of the bottle shaker experiments (p80?=???75 μm) comprises 60% Carbon Leader Reef, 20% Ventersdorp Contact Reef and 20% Black Reef and yields 92% recovered Au over a leach period of 40 h. Blended ores with high carbonaceous material (>?1 wt% carbonaceous material, (Black Reef?=?36–60%) yield lower recoveries of 60–69% Au). Ore leaching at the mixed-bed reactor column (??75 μm and ??5.6/+?4 mm) yields about 70% over a leach period of two weeks. We therefore suggest that the feasibility of ore blending is strongly controlled by the mineralogy of the constituent ores and that a mixed-bed reactor may be a viable alternative method for leaching of the low-grade Witwatersrand gold ores. Material from certain reefs, such as the Black Reef, has synergistic/antagonistic (nonadditive) blending effects. The overall implication of this study is that ore blending ratios, effects of comminution on mineral liberation, an association of gold with other minerals, and gold adsorption behavior will greatly inform future technology choices in the area of geometallurgy.

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199.
Lime softening produces an estimated 10,000 metric tons of dry drinking water treatment wastes (DWTW) per year, costing an estimated one billion dollars annually for disposal worldwide. Lime softening wastes have been investigated for reuse as internal curing agents or supplementary cementitious materials in concrete as well as a high-capacity sorbent for heavy metal removal. Lead, cadmium, and zinc are common heavy metals in groundwater contaminated by mine tailings. Cement-based filter media (CBFM) are a novel material-class for heavy metal remediation in groundwater. This study investigated the incorporation of DWTW as a recycled, low-cost additive to CBFM for the removal of lead, cadmium, and zinc. Jar testing at three different metal concentrations and breakthrough column testing using synthetic groundwater were performed to measure removal capacity and reaction kinetics. Jar testing results show as DWTW content increases at low concentrations, removal approaches 100% but at high metal concentrations removal decreases due to saturation or exhaustion of the removal mechanisms. Removal occurs through the formation of metal carbonate precipitates, surface sorption, and ion exchange with calcium according to the preferential series Pb+2 > Zn+2 > Cd2+. Removal kinetics were also measured through column testing and exceeded estimated calculations derived from batch jar testing isotherms due to the large formation of oolitic metal carbonates. Lead, cadmium, and zinc was concentrated in the column precipitates from 0.29, 0.23, and 20.0 μg/g in the influent solution to approximately 200, 130, 14,000 μg/g in the reacted DWTW-CBFM. The control and DWTW-CBFM columns had statically similar removal for zinc and lead. In the DWTW-CBFM, cadmium had decreased removal of approximately 25% due to proportionately decreased hydroxide content from cement replacement with 25% DWTW. This study shows the potential for DWTW as an enhancement to CBFM, thereby valorizing an otherwise waste material. Furthermore, the concentrative abilities of CBFM through precipitate and oolitic mineral formation could provide a minable waste product and close the waste-product cycle for DWTW.  相似文献   
200.
Submersed macrophytes are important in nutrient cycling in marine and lacustrine systems, although their in nutrient exchange in tidally-influenced riverine systems is not well studied. In the laboratory, plants significantly lowered porewater nutrient pools of riverine sediments compared with bare controls. Deep-rootedVallisneria americana lowered the porewater nutrients to a greater extent than the shallow-rootedPotamogeton pectinatus. V. americana showed significantly higher tissue nutrient content (N in roots, P in leaves) thanP. pectinatus. porewater nutrients in the river increased from spring to summer (1995) when vegetation was at its peak (for porewater PO4-P, p<0.05). In 1996, porewater nutrients were higher during peak plant biomass in the summer than in the fall (for porewater PO4-P, p<0.05). In the summer (1995) vegetated patches had significantly greater porewater PO4-P than bare patches. We hypothesize that the concentrating of particulates in riverine grassbeds and subsequent microbial processing may provide an indirect source of nutrients for submersed macrophytes. In tidally-influenced riverine systems, biological mechanisms such as root uptake of nutrients and lateral oxygen release may be masked by the interaction of physical forces (i.e., tides, currents) with the structure of the grassbeds.  相似文献   
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