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261.
Systematic marine conservation planning in data-poor regions: Socioeconomic data is essential 总被引:1,自引:0,他引:1
Natalie C. Ban Gretchen J.A. Hansen Michael Jones Amanda C.J. Vincent 《Marine Policy》2009,33(5):794-800
Systematic planning for conservation is highly regarded but relies on spatially explicit data that are lacking in many areas of conservation concern. The decision support tool Marxan is applied to a reef system in the central Philippines where 30 marine protected areas (MPAs) have been established in communities without much use of biophysical data. The intent was to explore how Marxan might assist with the legally required expansion to protect 15% of marine waters, and how existing MPAs might affect that process. Results show that biophysical information alone did not provide much guidance in identifying patterns of conservation importance in areas where the data are poor. Socioeconomic data were needed to distinguish among possible areas for protection; but here, as elsewhere in marine environments, the availability of such data was very limited. In the final analysis, local knowledge and integrated understanding of socioeconomic realities may offer the best spatially explicit information. The 30 existing MPAs, which encompassed a small proportion of the reef system, did not limit future options in developing a suite of MPAs on a broader scale. Rather, they appeared to generate the support for MPAs that is obligatory for any larger zoning effort. In summary, establishing MPAs based on community-driven criteria has biological and social value, but efforts should be made to collect ecological and socioeconomic data to guide the continued creation of MPAs. 相似文献
262.
In Belgium a long process (1999–2005) led to the designation of several marine protected areas (MPAs). In order to analyse the designation process, the ‘policy arrangement approach’ was used as an analytical tool. Attention was given to four dimensions (actors and coalitions, arguments, rules and resources). Particular attention was paid to the switch from an authoritative to a more deliberated policy style in reaction to conflicts with stakeholders. This switch in policy style contributed to a successful legal designation, but does not guarantee the best protection of marine biodiversity. This case study linked science (setting ecological goals) to policy (analysis of a policy process) and led to some more general conclusions on the designation of MPAs and the role of participation in this process. 相似文献
263.
Community-based coastal resource management (CBCRM) is a major conservation and fisheries management strategy in the tropics. In this study, the performance of 16 CBCRM programs in the Philippines was assessed using a meta-analysis of eight indicators that represented the perceptions of local resource users. Overall, the CBCRM programs in the Philippines were perceived to have a significant positive impact. However, the performance of each of the indicators was mixed. Although the CBCRM programs were perceived to be effective in empowering the local fishing communities, their perceived impact on improving the state of the local fisheries resources remained limited. This highlights the importance of incorporating ecological and socio-economic considerations in setting fisheries management regimes. 相似文献
264.
Since the 1980s, there have been continuous increases in the coverage of marine protected areas (MPAs) in China, and a total of 158 MPAs have been declared. The MPA system in China is characterized by (1) decentralised designation and management with reduced control from the central government; (2) a dominance of de jure fully protected MPAs that are often implemented as de facto multiple-use areas; and (3) a lack of objective evaluation processes. To improve China's MPA system requires an appropriate integration of fully protected and multiple-use MPAs, and an approach that balances the advantages of top-down and bottom-up approaches. 相似文献
265.
太湖和洪泽湖大银鱼(Protosalanx hyalocranius)体内元素的积累特征及产地判别 总被引:2,自引:0,他引:2
应用电感耦合等离子质谱仪分析技术分别研究了江苏太湖和洪泽湖水域大银鱼体内12种元素的生物积累特征.结果表明,两水域大银鱼体内元素含量的总体范围为:钙(Ca)9443-22150、钠(Na)1107-2418、镁(Mg)876.8-1231、钾(K)4662-9472、锌(Zn)74-135.8、锰(Mn)6.80-21.08、硒(Se)2.082-6.261、铜(Cu)0.489-2.704、铁(Fe)未检出-24.19、钻(Co)未检出-4.84、砷(As)0.123-0.587 mg,kg干重;镉(cd)未检出;必需元素丰富.太湖水域大银鱼中的Na、K、Cu、As、Se 的含量显著地高于洪泽湖水域大银鱼.而后者体内Ca、Mg、Zn的含量显著地高于前者.主成分分析显示出两水域鱼体多元素生物积累的整体"指纹"地理差异非常明显.在此基础上推导出了通过元素"指纹"来区分两地大银鱼个体的判别函数,正确率达100%.两水域大银鱼中毒性元素As和Cd的含量都远低于国家相应的限量标准. 相似文献
266.
通过对海南岛海岸带野外考察,在文昌市铜鼓岭石头公园观察到高程为30m的海平面遗迹,在东方市黄流镇观察到高程为25~35m的海平面遗迹,在三亚市鹿回头观察到高程为2.5m的海平面遗迹。综合研究前人在该区关于海平面变化的研究成果,得出如下几点初步认识:(1)南海及其周缘地区中全新世以来海平面呈下降趋势,海平面最高位置出现在7000a左右、高于现代海平面3m左右的位置;(2)南海中全新世以来海平面遗迹所揭示的古海平面高程的差异性是古海平面本身持续下降和该区地壳差异性垂直运动共同作用的结果;(3)南海及其周缘地区中全新世期间中央海盆及其西缘的珠江口、红河、湄公河和昭披耶河4个河流三角洲地区为构造沉降区,而南海周缘的台湾岛、雷州半岛、印支半岛、南马来半岛、爪哇岛和苏拉威西岛6个地区为构造抬升区,抬升幅度最大的地方在台湾岛。 相似文献
267.
The occurrence percentage and abundance of General Aerobic Hetero- trophic Bacteria (GAB) were determined by using the method of MPN for 182 sub- samples from 10 sediment cores taken from the Canadian basin and the Chukchi Sea at two different culturing temperatures. The results showed that the general occurrence percentage of GAB was quite high, average abundanees of GAB at cultured temperatares of 4℃ and 25℃ were 4.46 ×10^7 and 5.47×10^7 cells·g^-1(wt), respectively. The highest abundance of GAB occurred at 20 -22 cm section in the sediment. GAB abundances changed among the section of sediments, but there is a trend : the a-bundances at the middle or lower sections were lower than those at upper section. Cultivation at 25℃ could improve the occurrence percentage and abundances of GAB, which suggests that the increasing of temperature may change the living circum-stances of GAB. The differences of GAB among the latitudes areas indicated that occurrence percentage and abundances of GAB in middle latitude areas were higher than those in the higher or lower latitude areas, and were more obvious at 4℃ than those at 25℃. The GAB abundances in sediment under the shallower water seemed to be low- er than those in sediments under the deeper water and this status was more obvious at 25℃ than that at 4℃. 相似文献
268.
269.
利用湘东南东江流域1959~2006年共48年的历史资料,采用统计分析方法,对东江流域历年雨水集中期的气候规律以及2006年雨水集中期的特征及成因进行了分析。分析结果表明:东江流域历年的雨水集中期多出现在6月和8月;东江流域雨水集中期的出现,受台风的影响较大。2006年由于04号台风"碧利斯"的影响导致了本年的雨水集中期出现在7月中旬,其特征是降水强度强、强降水范围广、过程降雨量大,而大尺度引导气流、南海季风对"碧利斯"的西行路径及降水强度影响较大。 相似文献
270.
Formation of saddle dolomites in Upper Cambrian carbonates, western Tarim Basin (northwest China): Implications for fault-related fluid flow 总被引:1,自引:0,他引:1
Juntao Zhang Wenxuan Hu Yixiong Qian Xiaolin Wang Jian Cao Jingquan Zhu Qing Li Xiaomin Xie 《Marine and Petroleum Geology》2009,26(8):1428-1440
The saddle dolomites occur more intensely in cores closely to fault than that in cores far away from the fault in Upper Cambrian carbonate of western Tarim basin, suggesting that formation of the saddle dolomites is likely related to fault-controlled fluid flow. They partially fill in fractures and vugs of replacement dolomite. The saddle dolomites exhibit complex internal textures, commonly consisting of core and cortex. In comparison with the matrix dolomites, the saddle dolomites show lower Sr-content and 87Sr/86Sr ratios, higher Fe- and Mn-content, and more negative δ18O values. Combined with high Th (100–130 °C) of primary fluid inclusions, it is suggested that the saddle dolomites precipitated from hydrothermal fluid derived from the deep evaporite-bearing Middle Cambrian strata, and the magnesium source may be due to dissolution of host dolomite during hydrothermal fluid migration. Fault activity resulted in petrographic and geochemical difference of the core and cortex of the saddle dolomites. The cores precipitated from the formation water mixed by deep brines at the early stage of fault activity, and the cortexes precipitated from the deep fluid with higher temperatures through the Middle Cambrian later. In summary, the formation of the saddle dolomites implies a hydrothermal fluid event related to fault activity, which also resulted in high porosity in Upper Cambrian carbonate in western Tarim Basin. 相似文献