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1.
Ocean Science Journal - Biological monitoring has become one of the most widely used approaches in aquatic monitoring. As a result, the effect of the xenobiotics entrained by the organic and...  相似文献   
2.
Kahramanmaras and its surroundings are under the influence of East Anatolian and Dead Sea fault zones which have significance in the tectonics of Turkey. The long-term energy accumulation in these zones creates a very high risk level in terms of seismic hazard. In this study, the seismic hazard of Kahramanmaras Province and its vicinity was tried to be determined by using the probabilistic seismic hazard method approach. The earthquake catalog used in the study comprises 424 earthquakes equal or greater than M w ?=?4.0, covering a time period between 1 January 1900 and 1 January 2015. The earthquake data have been compiled from the catalogs of the International Seismological Center (ISC), Republic of Turkey Prime Ministry Disaster and Emergency Management Precidency (RTPMDEMP), Bogazici University Kandilli Observatory and Earthquake Research Institute. Seismic sources that could affect the study area have been identified according to the Earthquake Model of the Middle East (EMME). Seismic hazard parameters and peak horizontal acceleration values were obtained by using the selected attenuation relationships, and the results were given with iso-acceleration maps corresponding to a recurrence period of 475 years. The calculated peak horizontal acceleration values are generally varying between 0.21 and 0.41 in the study area. The result of this study shows that the southeastern parts of the study area have a greater seismic hazard compared with other parts.  相似文献   
3.
Herero communities in northern Namibia recently formed the Ehi-rovipuka Conservancy under a national Community-Based Natural Resource Management Programme (CBNRM) that has received international acclaim for wildlife conservation and poverty alleviation. Nearly a century ago ancestors of the Herero were ousted from Etosha National Park, contiguous to the Ehi-rovipuka Conservancy. The communities have been denied access ever since. Participatory Rural Appraisal (PRA) methods were employed to elucidate relationships of the Herero and their communal conservancy with the Etosha National Park. Memory mapping and villager interviews revealed a profound sense of lost traditional territory inside Etosha and a strong desire to return to the Park, not to harvest wildlife but to restore cultural practices and reap certain benefits from the Park. We term the separation of the communities from their traditional territory as a ‘decoupling’ of people from their local environment. We further suggest that the potential benefits that villagers identify from the Park represent mechanisms for ‘recoupling’ local social-ecological systems, requiring the literal and figurative breakdown of the Park fence. We describe a model to illustrate decoupling and recoupling mechanisms, and argue that recoupled social-ecological systems are necessary for long-term conservation of biodiversity. We further suggest a collaborative landscape model for biodiversity conservation featuring institutional linkages and integration between community-conserved areas, integrated conservation corridors for connectivity, and dynamic, mobile reserves collaboratively integrated with national parks management. This model may have applicability in Namibia and similar regions elsewhere with low population densities, high species endemism and prevailing or emerging threats to biodiversity.  相似文献   
4.
Co-management institutional arrangements have an important role in creating conditions for social learning and adaptation in a rapidly changing Arctic environment, although how that works in practice has not been clearly articulated. This paper draws on three co-management cases from the Canadian Arctic to examine the role of knowledge co-production as an institutional trigger or mechanism to enable learning and adapting. Experience with knowledge co-production across the three cases is variable but outcomes illustrate how co-management actors are learning to learn through uncertainty and environmental change, or learning to be adaptive. Policy implications of this analysis are highlighted and include the importance of a long-term commitment to institution building, an enabling policy environment to sustain difficult social processes associated with knowledge co-production, and the value of diverse modes of communication, deliberation and social interaction.  相似文献   
5.
A palaeomagnetic study is reported from the lavas of Eocene, Miocene and Pliocene age cropping out immediately to the north of the North Anatolian Fault Zone (NAFZ) in the Re?adiye–Mesudiye region of central-eastern Anatolia. Rock magnetic investigations identify a high percentage of multi-domained magnetite as the dominant ferromagnet in these rocks and this probably accounts for a relatively poor response to alternating field and thermal demagnetisation. Thirty of 37 units yielded acceptable groupings of characteristic magnetisation directions. An earlier study indicated small anticlockwise crustal block rotation in this region since Upper Cretaceous times (D/I?=?347/50°), and our study indicates that this was overtaken by clockwise rotation in Eocene times (D/I?=?40/47°), although sample size control from the Palaeogene is poor. Results from later Miocene (D/I?=?2/62°) and Pliocene (D/I?=?0/53°) volcanic rocks indicate that no significant tectonic rotation has occurred in the north of the NAFZ in Neogene times. This contrasts with rotations in the weaker crust comprising the Anatolian collage south of the NAFZ, where differential and sometimes large anticlockwise rotations occurred during the latter part of the Neogene.  相似文献   
6.
This study defines the Late Cenozoic stress regimes acting around the Bolu Basin along the North Anatolian Fault in northwestern Turkey. The inferred regional stress regime, obtained from the inversion of measured fault-slip vectors as well as focal mechanism solutions, is significant and induces the right-lateral displacement of the North Anatolian Fault. The field observations have also revealed extensional structures in and around the Bolu Basin. These extensional structures can be interpreted as either a local effect of the regional transtensional stress regime or as the result of the interaction of the fault geometries of the dextral Duzce Fault and the southern escarpment of the North Anatolian Fault, bordering the Bolu Basin in the north and in the south, respectively.The inversion of slip vectors measured on fault planes indicates that a strike-slip stress regime with consistent NW- and NE-trending σHmax(σ1) and σHmin(σ3) axes is dominant. Stress ratio (R) values provided by inversion of slip vectors measured on both major and minor faults and field observations show significant variations of principal stress magnitudes within the strike-slip stress regime resulting in older transpression to younger transtension. These two stress states, producing dextral displacement along NAF, are coaxial with a consistent NE-trending σ3 axis. The earthquake focal mechanism inversions confirm that the transtensional stress regime has continued into recent times, having identical horizontal stress axis directions, characterized by NW and NE-trending σ1 and σ3 axes, respectively. A locally consistent NE-trending extensional, normal faulting regime is also seen in the Bolu Basin. The stress-tensor change within the strike-slip stress regime can be explained by variations in horizontal stress magnitudes that probably occurred in Quaternary times as a result of the westward extrusion of the Anatolian block.  相似文献   
7.
The study area is located between Çorum and Amasya along the Ezinepazar?–Sungurlu Fault Zone (ESFZ) which is regarded as the splay of the North Anatolian Fault Zone (NAFZ). By this study, the 1/25,000 scaled geological map of the study area was prepared, and its stratigraphic and tectonic characteristics were unraveled as a result of palaeontological and petrographical analyses of the samples collected from different rock units. Particularly, geologic ages of the Late Jurassic–Early Cretaceous Ferhatkaya and Carcurum and Middle Eocene Çekerek formations were provided from palaeontological determinations. Using Landsat TM and Shuttle Radar Topography Mission 3 (SRTM 3) data of the region, the borders between the rock units and the tectonic characteristics in the study area were clarified by spectral and spatial enhancement methods. Kinematic characteristics of ESFZ obtained from the young sedimentary rocks along both sides of the fault zone were also inferred in this study. Understanding the kinematic and geometrical characteristics of the faults is important in terms of the seismotectonics of the region. In the statistical study conducted on the basis of the directions of the lineaments indicates the highest concentrations in general between N 50° - 60° E and N 60° - 70° E. Band 7 of the study area was enlightened in SE direction taking into consideration the relation of the geologic structures in the region with NAFZ and ESFZ and their general strike directions. Along with the formation of NAFZ, the region has undergone a counterclockwise rotation of approximately 20°–30°, which has developed between the “splay” faults in the south block of that fault. These faults are strike-slip faults formed under the compressional regime roughly in a NW–SE direction. It is noted that this tectonic regime has developed under compression in NW–SE direction, which was dominant in similar kinematic analysis studies conducted on NAFZ.  相似文献   
8.
The growing interest in the understanding of community resilience suggests a need for improving research approaches. This article reviews methods used to date, and suggests opportunities for expanding the range and efficacy of approaches used to understand, improve, and monitor the coupled social and ecological aspects of community resilience. We explore three potential foci: research approaches that enhance understanding of community resilience; those that help to improve community resilience through the research process; and the further development of methods to guide monitoring. Most studies have relied on mixed and multistaged methods, including in-depth interviews and case studies. We comment on the wide range of approaches used, and suggest others that could be valuable. There is particular scope for greater use of cumulative studies, historical or retrospective studies, participatory methods, and systems approaches, and a need for more methods that explore the coupling of social and ecological dimensions.  相似文献   
9.
Recent studies have focused on the study of social networks among local resource users, but few have attempted to study co-management networks. The objective of the research was to assess the Chilean shellfish co-management system from an organizational network perspective. Starting with one detailed case study, representatives of 38 small-scale fisher associations from two administrative regions were interviewed to investigate: (1) networks of actors in each co-management case, (2) the functions of these actors in co-management, and (3) fisher perceptions about Chile's co-management arrangement. Results indicate that decision-making is highly centralized and power is concentrated in government, with little horizontal exchange and cooperation among fisher associations. However, the network approach indicates the presence of a rich set of players, some seven sets of actors by function. Grassroots management innovations are hampered by the existing co-management structure, suggesting that the system may benefit from a modification of the policy to allow greater learning-by-doing and flexibility.  相似文献   
10.
This paper reports on the outcomes of a project that engaged researchers and fishers together in adapting participatory social science approaches to the purposes and the constraints of community-based fisher organizations. The work was carried out in the Scotia-Fundy Region of Atlantic Canada (the Bay of Fundy and Scotian Shelf) between 1999 and 2003. After a period of reflection on what was collectively learned from our experiences in this project, the academics went back to the community partners in a recent workshop for further discussion and refinement of the lessons. We conclude that true participatory fishery research, utilized in support of community-based management, can be a particularly powerful tool. However, it has few effective shortcuts, it must deal early in the research process with power imbalances, and it should involve significant political engagement and empowerment through co-learning. This assessment of participatory research in coastal fisheries also has significant implications for how we think of social capital and on how we may develop community-based resource management for a sustainable future.  相似文献   
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