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51.
Mi-Kyung Yoon Mikhail Baykulov Stefan Dümmong Heinz-Jürgen Brink Dirk Gajewski 《International Journal of Earth Sciences》2008,97(5):887-898
The influence of deep crustal processes on basin formation and evolution and its relation to current morphology is not well
understood yet. A key feature to unravel these issues is a detailed seismic image of the crust. A part of the data recorded
by the hydrocarbon industry in the late 1970s and 1980s in the North German Basin were released to the public recently. The
seismic reflection data were recorded down to 15 s two-way travel time. The mean Common Midpoint fold of about 20 is relatively
low compared to contemporary seismic acquisitions. The processing of the 1980s focussed on the sedimentary structures to explore
the hydrocarbon potential of this area. We applied the Common Reflection Surface stack technique to the data sets, which is
well suited for low-fold data. The reprocessing was focussed on the imaging of the subsedimentary crustal range. The reprocessed
images show enhanced reflections, especially in the mid and lower crustal part. Also, the image of the salt structures in
the graben area was improved. Furthermore, the reprocessed images indicate an almost flat Moho topography in the area of the
Glückstadt Graben and an additional lower crustal structure, which can be correlated with a high-density body found in recent
gravity modeling studies. 相似文献
52.
Stacy D. Jupiter Graham Epstein Natalie C. Ban Sangeeta Mangubhai Margaret Fox Michael Cox 《社会与自然资源》2017,30(9):1096-1111
Locally managed marine areas (LMMAs) are often recommended as a strategy to achieve conservation and fisheries management, though few studies have evaluated their performance against these objectives. We assessed the effectiveness of eight periodically harvested closures (PHCs), the most common form of management within Fijian LMMAs, focusing on two outcomes: protection of resource units and biodiversity conservation. Of the eight PHCs, only one provided biodiversity benefits, whereas three were moderately successful in protecting resource units (targeted fish biomass). Protection of resource units was more likely when PHCs were harvested less frequently, less recently, and when total fish biomass in open areas was lower. Our findings further suggest that monitoring, enforcement, and clearly defined boundaries are critical, less frequent harvesting regimes are advised, and culturally appropriate management incentives are needed. Although PHCs have some potential to protect resource units, they are not recommended as a single strategy for broad-scale biodiversity conservation. 相似文献
53.
54.
《Geoforum》2016
Common property resources (CPRs) have provided a basis for sustenance to countless households, especially those that lack access to private assets. Several factors have eroded the access of CPR dependent communities, such as, conscious policy decisions of the state, elite domination, the process of land consolidation and commercialization. In the period of neo-liberal reforms in India, after 1991, the nature of threats to the commons has changed. Emerging factors such as urbanization, land acquisition and real estate development have played a more significant role in depleting the CPRs. The commons have increasingly come to bear the ecological foot-print of urbanization as they got acquired or encroached upon for urban expansion and required infrastructure. This compromises the livelihood security of those who depend on them for sustenance. There is a need for debate on alternative and more sustainable models of urbanization. 相似文献
55.
《Marine Policy》2016
The conservation of marine biological diversity has been identified as a crucial issue in need of legal regulation. The UNCLOS does not sufficiently address all issues relevant to viably conserve biological diversity. Legal developments concerning marine genetic resources, area-based management tools such as marine protected areas, environmental impact assessment and capacity building are being discussed as elements of a new implementing agreement. In particular, more precise legal rules concerning marine protected areas beyond national jurisdiction are needed to supplement the frame left by UNCLOS. As concerns the issue of access to genetic resources and the sharing of benefits the UNCLOS regime has gaps because the relevant activities had not been foreseen at the time of the convention's adoption. Divergent views exist as to whether the concept of the common heritage of mankind should be extended to genetic resources. 相似文献
56.
《Marine Policy》2016
The 1982 United Nations Convention on the Law of the Sea declares the seabed beyond national jurisdiction and its mineral resources as the “common heritage of mankind” (CHM). This article examines the operationalisation of the CHM principle in the international seabed mining regime, with focus placed on the sharing of benefits derived from mining. The article begins by providing an overview of the CHM principle, before examining four modalities provided for in the Convention, both institutional and substantial, and their role in giving effect to the CHM principle: (1) financial benefits; (2) the “Enterprise”; (3) the parallel system of reserved areas; and, (4) marine scientific research. Finally, overarching issues are discussed and some suggestions on ways forward are presented. The article considers that the deep seabed mining regime is not yet ready to effectively share the benefits derived from the common heritage of mankind. In particular, the future of the Enterprise is uncertain and changes to the so-called parallel system that affect the CHM have received minimal discussion. Moreover, a lack of publicly available research data related to seabed mining is hindering current benefits for humankind. However, work is underway at the International Seabed Authority to establish rules and policies with respect to the sharing of financial benefits. While the CHM principle remains largely untested, approaches that are transparent, inclusive, accountable, and equitable are more likely to be successful. 相似文献
57.
Towards a better understanding of hydrological interactions between the land surface and atmosphere, land surface models are routinely used to simulate hydro-meteorological fluxes. However, there is a lack of observations available for model forcing, to estimate the hydro-meteorological fluxes in East Asia. In this study, Common Land Model (CLM) was used in offline-mode during the summer monsoon period of 2006 in East Asia, with different forcings from Asiaflux, Korea Land Data Assimilation System (KLDAS), and Global Land Data Assimilation System (GLDAS), at point and regional scales, separately. The CLM results were compared with observations from Asiaflux sites. The estimated net radiation showed good agreement, with r =0.99 for the point scale and 0.85 for the regional scale. The estimated sensible and latent heat fluxes using Asiaflux and KLDAS data indicated reasonable agreement, with r = 0.70. The estimated soil moisture and soil temperature showed similar patterns to observations, although the estimated water fluxes using KLDAS showed larger discrepancies than those of Asiaflux because of scale mismatch. The spatial distribution of hydro-meteorological fluxes according to KLDAS for East Asia were compared to the CLM results with GLDAS, and the GLDAS provided online. The spatial distributions of CLM with KLDAS were analogous to CLM with GLDAS, and the standalone GLDAS data. The results indicate that KLDAS is a good potential source of high spatial resolution forcing data. Therefore, the KLDAS is a promising alternative product, capable of compensating for the lack of observations and low resolution grid data for East Asia. 相似文献
58.
The toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and its related planar halogenated aromatic hydrocarbons (PHAHs) are mediated by the aryl hydrocarbon receptor (AHR). To investigate the potential sensitivity to PHAHs and the evolutional diversity of AHR in aquatic birds, AHR cDNAs were initially cloned and sequenced from the livers of a black-footed albatross (Diomedea nigripes) and a common cormorant (Phalacrocorax carbo). In this study, we report the identification of two distinct AHR paralog genes in these species. The two full-length AHR cDNAs from albatross were highly divergent (33% overall amino acid identity, and 60% identity in the N-terminal half). Phylogenetic analysis showed that one of them belongs to the AHR1 clade and the other one to the AHR2 clade, which has been identified only from fishes, but not yet from mammals and birds. Albatross AHR1 encoded a 861-residue protein with a predicted molecular mass of 96.7 kDa, and in the case of albatross AHR2, 925 amino acids and 100.7 kDa. From cormorant liver, the full-length AHR1 cDNA and the partial AHR2 cDNA were cloned. This result strongly suggests that bird species also possess two distinct AHR genes (AHR1 and AHR2). To our knowledge, this is the first report on the presence of an AHR2-like isoform in bird species as well as in fish. 相似文献
59.
Juan C. Surís-Regueiro Manuel M. Varela-Lafuente Carlos Iglesias-Malvido 《Marine Policy》2003,27(6):535-544
This paper presents an analysis of the effectiveness of the community structural policy in the fisheries sector by comparing the relative level of compliance with objectives (reduction of fleets and economic viability) with the mechanisms that have been implemented (structural funds and allocation of quotas). On the one hand, this analysis shows that there is a positive correlation between the level of structural funds and the attainment of goals. On the other hand, it was found that the greater the relative availability of quotas, the poorer the countries performed in complying with the objective of reducing the fishing capacity, and the higher the expectations of achieving acceptable yields. These correlations, however, were not very strong. 相似文献
60.