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51.
Hu  Dunxin  Wang  Fan  Sprintall  Janet  Wu  Lixin  Riser  Stephen  Cravatte  Sophie  Gordon  Arnold  Zhang  Linlin  Chen  Dake  Zhou  Hui  Ando  Kentaro  Wang  Jianing  Lee  Jae-Hak  Hu  Shijian  Wang  Jing  Zhang  Dongxiao  Feng  Junqiao  Liu  Lingling  Villanoy  Cesar  Kaluwin  Chalapan  Qu  Tangdong  Ma  Yixin 《中国海洋湖沼学报》2020,38(4):906-929
The Western Tropical Pacific(WTP) Ocean holds the largest area of warm water(28℃) in the world ocean referred to as the Western Pacific Warm Pool(WPWP),which modulates the regional and global climate through strong atmospheric convection and its variability.The WTP is unique in terms of its complex 3-D ocean circulation system and intensive multiscale variability,making it crucial in the water and energy cycle of the global ocean.Great advances have been made in understanding the complexity of the WTP ocean circulation and associated climate impact by the international scientific community since the 1960 s through field experiments.In this study,we review the evolving insight to the 3-D structure and multi-scale variability of the ocean circulation in the WTP and their climatic impacts based on in-situ ocean observations in the past decades,with emphasis on the achievements since 2000.The challenges and open que stions remaining are reviewed as well as future plan for international study of the WTP ocean circulation and climate.  相似文献   
52.
In low-lying areas of urban and suburban regions in Asia, the use of landfill has allowed urban land use to encroach onto watery landforms, such as back marshes, which were formerly used as rice fields. To improve understanding of the associations between land-use patterns and landfill development, we carried out a case study in the urban fringe of Metro Manila in the Philippines. We examined landfill volume derived from land-use change using GIS, and field surveyed qualitative aspects of the landfill used. We calculated the rate of application of landfill in low-lying housing development areas to be 5.0 × 10m3 km?2 year?1, most of which consisted of offsite disposal of construction waste or crushed rock produced by urban development and renewal on the adjoining uplands. The flow of fill material from offsite sources to onsite landfill development areas was on the basis of individual agreements between suppliers and developers.  相似文献   
53.
Aqueous Surfactant Washing of Residual Oil Contamination from Sandy Soil   总被引:2,自引:0,他引:2  
A laboratory study was conducted to determine the efficiency of different aqueous concentrations of an alcohol ethoxylate surfactant in washing residual levels of an oil [automatic transmission fluid (ATF)] from sandy soil. Five glass columns packed with the soil were prepared in a manner that simulated conditions leading to residual saturation in an actual oil leak. Each of four columns was washed continuously with 28 pore volumes of solution by pumping either 0.0 percent (water), 0.5 percent, 1.0 percent, or 2.0 percent aqueous surfactant solutions through the columns. The fifth column was washed intermittently with 28 pore volumes of a 1.0 percent surfactant solution. Water washed only 25.5 percent of the ATF from the column soil, while the 0.5 percent, 1 percent, and 2 percent surfactant solutions washed 55 percent, 60 percent, and 72.8 percent of the ATF, respectively. The distribution of the ATF remaining in the column after washing showed that the ATF removed by water was mainly from the outlet side of the column, while the ATF removed by the 2.0 percent surfactant solution was mainly from the inlet side of the column. This observation indicated that different mechanisms were involved; namely, the displacement of oil through the soil-pore space, the dispersion of oil due to reduced surface tension, and the solubilization of oil by surfactant micelles. In the case of water, the displacement of oil was the main washing mechanism, while all three mechanisms were operative during surfactant washing. ATF dispersion and solubilization were improved at higher surfactant concentrations. The column that was washed intermittently to pulse ATF from dead end pores did not show a significant improvement over the column that was continuously washed with the same 1.0 percent surfactant solution. The results show promising potential for application in the field and will be further investigated in a two-dimensional model aquifer.  相似文献   
54.
The Batang Group in the Zhaokalong area not only hosts an important Fe-Cu polymetallic deposit but also reveal important insights for the Late Triassic tectonism in the northern Sanjiang region. In order to delineate the tectonic setting and evolutionary process of the paleo arc-basin system, geochemical studies on the Batang Group strata have been carried out. The results suggest that andesite in the Zhaokalong area mainly belongs to the tholeiite series and is characterized by obvious fractionation of LREE and HREE, enrichment in LILE and depletion in HFSE, and a distinctly elevated δ~(34)SCDT average of 10.5‰. The sandstone is classified as lithic sandstone, which is also characterized by obvious fractionation of LREE and HREE, as well as weak negative Ce and Eu anomalies. The limestone displays positive Eu anomalies, with δ~(13)CPDB ranging from-1.3‰ to 4.4‰ and δ~(18) OSMOW ranging from 14.6‰ to 22.5‰. These results indicate that the andesite has a dual signature of both arc andesite and rift volcanic rocks, whereas the sandstone may be formed in an active continental margin, and the limestone could be deposited in a weak oxidizing shallow sea. The sandstone in the Zhaokalong area represents sedimentation in a platform slope facies, corresponding to the main stage of the Jinshajing oceanic basin subduction during the middle period of Late Triassic. The continental arc volcanic activity resulted from subsequent strengthened subduction, forming the andesite in the North Qiangtang backarc basin. Afterwards, the limestone was formed after the cessation of magmatic activity. The information gleaned from the Batang Group strata helped constrain the evolution of the paleo-Jomda island arc and Jinshajiang oceanic subduction in the Late Triassic.  相似文献   
55.
Participatory diagnosis is an approach to identify, prioritize and mobilise around factors that constrain or enable effective governance and management in small-scale fisheries. Diagnostic frameworks are mostly designed and used for systematic scientific analysis or impact evaluation. Through participation they also have potential to guide contextually informed improvements to management in practice, including transitions to contemporary forms of governance like the ecosystem approach to fisheries (EAF)—the focus of our study. We document and critically reflect on participatory diagnosis processes and outcomes at sites in Indonesia, Philippines, Solomon Islands and Tanzania. These sites were part of an international project on the implementation of the EAF and differed widely in institutional and operational contexts. The Participatory Diagnosis and Adaptive Management framework and the “issue radar” diagnosis map were used to identify, evaluate and address factors associated with navigating management transitions towards the EAF. We found that many challenges and priority actions identified by participants were similar across the four study countries. Participants emphasized habitat restoration, particularly mangrove rehabilitation, and livelihood enhancement. The importance of strengthening governance entities, networks and processes (e.g., harmonization of policies, education and awareness of policies) was also a prominent outcome of the diagnosis. Site-specific factors were also explored together with the differing views among stakeholders. We conclude that diagnosis frameworks are indeed useful tools for guiding management transitions in fisheries, particularly where they enable flexibility in approaches to diagnosing problems and applying solutions to local contexts.  相似文献   
56.
Research on vulnerability and adaptation in social-ecological systems (SES) has largely centered on climate change and associated biophysical stressors. Key implications of this are twofold. First, there has been limited engagement with the impacts of social drivers of change on communities and linked SES. Second, the focus on climate effects often assumes slower drivers of change and fails to differentiate the implications of change occurring at different timescales. This has resulted in a body of SES scholarship that is under-theorized in terms of how communities experience and respond to fast versus slow change. Yet, social and economic processes at global scales increasingly emerge as ‘shocks’ for local systems, driving rapid and often surprising forms of change distinct from and yet interacting with the impacts of slow, ongoing ‘trends’. This research seeks to understand the nature and impacts of social shocks as opposed to or in concert with trends through the lens of a qualitative case study of a coastal community in Mexico, where demand from international seafood markets has spurred rapid development of a sea cucumber fishery. Specifically, we examined what different social-ecological changes are being experienced by the community, how the impacts of the sea cucumber fishery are distinct from and interacting with slower ongoing trends and how these processes are affecting system vulnerability, adaptations and adaptive capacity. We begin by proposing a novel framework for conceptualizing impacts on social systems, as comprised of structures, functions, and feedbacks. Our results illustrate how the rapid-onset of this fishery has driven dramatic changes in the community. New challenges such as the ‘gold-rush-style’ arrival of new actors, money, and livelihoods, the rapid over-exploitation of fish stocks, and increases in poaching and armed violence have emerged, exacerbating pressures from ongoing trends in immigration, overfishing and tourism development. We argue that there is a need to better understand and differentiate the social and ecological implications of shocks, which present novel challenges for the vulnerability and adaptive capacity of communities and the sustainability of marine ecosystems.  相似文献   
57.
In countries like Sierra Leone, where stock assessments based on fisheries-independent data and complex population models are financially and technically challenging, catch statistics may be used to infer fluctuations in fish stocks where more precise data are not available. However, FAO FishStat, the most widely-used time-series data on global fisheries ‘catches’ (actually ‘landings’), does not account for Illegal, Unreported, and Unregulated (IUU) catches and relies on statistics provided by the national agencies of each member country. As such, reported FishStat data is vulnerable to changes in monitoring capacity, governmental transitions, and budgetary constraints, and may substantially underestimate the measure of extracted marine resources. In this report, Sierra Leone's total catches by all marine fishing sectors were estimated for the period 1950–2015, using a catch reconstruction approach incorporating national data, expert knowledge, and both peer-reviewed and grey literature. Results demonstrate that a substantial amount of marine resource exploitation is not represented in official statistics, and reconstructed catches represent more than 2.25 times the recorded FAO Fishstat values. Notably, foreign fleets take the vast majority of industrial catch in Sierra Leone's EEZ, indicating that most of the resource catch and revenue is diverted to foreign companies and export markets. While foreign actors dominate the industrial sector, the small-scale sector represents the majority of domestic catch. Illegal fishing is also a substantial challenge in Sierra Leone, and extracts a large amount of the country's marine fish resources. Reconstructing catches in Sierra Leone also highlights the impacts of various historical events such as Sierra Leone's civil war and post-war reconstruction on the development of the fisheries sector. The results found in the reconstruction present a large discrepancy from FishStat data, with considerable implications for assessment of stocks and management of Sierra Leone's marine resources.  相似文献   
58.
《Quaternary Science Reviews》2007,26(19-21):2685-2686
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