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1.
《Marine Policy》2017
Due to rapid declines of shark populations across many species and regions of the world, the need for large-scale conservation measures has become widely recognized. Some coastal states have opted to implement ‘Shark Sanctuaries’, which prohibit commercial shark fishing and the export of shark products across large areas, typically their entire Exclusive Economic Zones. Although shark sanctuaries cover almost as much area globally as marine protected areas (MPAs), their success has yet to be evaluated. Here, key features and regulatory details for eleven shark sanctuaries (covering 3% of global ocean area) are summarized, highlighting their commonalities and differences. Catch data are then used to shed light on the impact current shark sanctuaries could have on shark catch, foreign fleets, trade and abundance. Based on this comparative analysis, recommendations are made to implement program evaluation measures within existing and future shark sanctuaries that would explicitly outline goals and measures of success or failure. In summary, although shark sanctuaries may have the intended effect of reducing shark mortality, there appears a need to address bycatch within shark sanctuary regulations, and to collect baseline data that can be used to monitor sanctuary effectiveness. 相似文献
2.
T Sancelme J Goetze S Jaquemet MG Meekan A Flam AM Watts 《African Journal of Marine Science》2020,42(1):95-107
Coastal populations of maritime countries in eastern Africa rely on fish as a primary source of protein, but baseline information on the abundance of fish communities on these coastlines is often lacking. We used baited remote underwater video stations to compare the abundance and diversity of reef fishes targeted by fishing at two sites in southern Mozambique, one at Lighthouse Reef within the Bazaruto Archipelago National Park and the other to the south at San Sebastian Reef on the San Sebastian Peninsula. Fish that are known targets of fisheries (mostly small-scale and artisanal) had an abundance that was almost three-times greater at San Sebastian Reef (80.22 ind. h–1 [SE 18.00]) than at Lighthouse Reef (29.70 ind. h–1 [SE 8.91]). Similarly, there was greater mean species richness at San Sebastian Reef (38.74 species h–1 [SE 2.79]) than at Lighthouse Reef (25.37 species h–1 [SE 3.66]). The main drivers of targeted fish abundance were habitat and depth, with shallow (<15 m) and mixed reef areas having the greatest abundance and richness. More sampling was done over sand habitat at Lighthouse Reef, which likely led to the lower abundance and species richness observed at this site; however, that finding could also be attributable to the fact that protection is provided to only a section of available coral reef habitat in a small area. Nevertheless, fish community structure was comparable between the sites, with similar proportions of carnivores (78–81%), herbivores (12–14%) and omnivores (7–8%). Our findings highlight the variation in species abundance and assemblages of coral-reef fish targeted by fishing in Mozambique and emphasise the importance of localised environmental variables as a driver of these patterns. To ensure maximum protection of Lighthouse Reef fish communities, we recommend an extension of the no-take zone to include the entire reef complex. 相似文献
3.
Habitat degradation and fishing are major drivers of temporal and spatial changes in fish communities. The independent effects of these drivers are well documented, but the relative importance and interaction between fishing and habitat shifts is poorly understood, particularly in complex systems such as coral reefs. To assess the combined and relative effects of fishing and habitat we examined the composition of fish communities on patch reefs across a gradient of high to low structural complexity in fished and unfished areas of the Ningaloo Marine Park, Western Australia. Biomass and species richness of fish were positively correlated with structural complexity of reefs and negatively related to macroalgal cover. Total abundance of fish was also positively related to structural complexity, however this relationship was stronger on fished reefs than those where fishing is prohibited. The interaction between habitat condition and fishing pressure is primarily due to the high abundance of small bodied planktivorous fish on fished reefs. However, the influence of management zones on the abundance and biomass of predators and target species is small, implying spatial differences in fishing pressure are low and unlikely to be driving this interaction. Our results emphasise the importance of habitat in structuring reef fish communities on coral reefs especially when gradients in fishing pressure are low. The influence of fishing effort on this relationship may however become more important as fishing pressure increases. 相似文献
4.
The purpose of this paper is to describe the status and general faunal composition of sponge reefs in the Georgia Basin (GB), British Columbia, Canada. Fourteen distinct deep-water glass sponge (Hexactinellid) reefs have been mapped using multibeam bathymetry and sidescan sonar in the GB. Seven of these have been surveyed visually using video from remotely operated vehicles (ROVs). Analysis of video data indicated that three reefs were undamaged, two were damaged and the other two were damaged but potentially recovering. The nature of the damaged reefs, with large areas of scattered dead sponge skeleton fragments and few live reef-building sponges (Aphrocallistes vastus and Heterochone calyx), as well as video evidence of tracks suggest they were damaged mechanically by mobile fishing gear.Relative abundance of the megafauna associated with the reefs is discussed in the context of oceanographic conditions, such as sediment accumulation and organic flux, as well as overall reef status. Of particular interest for fisheries conservation efforts in the area was the fact that one undamaged reef in the southern GB showed higher taxonomic richness and abundance of rockfish (Sebastes spp.), both adult and juvenile, compared to an adjacent damaged reef. This result suggests that undamaged reefs may act as refugia for these endangered stocks. 相似文献
5.
《Marine Policy》2017
Coral reefs provide important ecological services such as biodiversity, climate regulation, and cultural benefits through recreation and tourism. However, many of the world's reefs are declining, with Caribbean reefs suffering a significant decline in living corals over the past half century. This situation emphasizes the need to assess and monitor reef conditions using a variety of methods. In this study, a new method for assessing reef conditions to inform management using participatory mapping by coral reef “experts” in the U.S. Virgin Islands (USVI) is described. Occupational SCUBA divers were recruited (n=87) to map coral reef conditions, uses, and threats (stressors) using an internet-based mapping website. The data reveal an uneven geographic distribution of reef conditions in the USVI with the most frequently mapped perceived healthy reef characteristics being: large amount of physical reef structure (n=872 markers); endangered or threatened species present (n=721); and large amount of live coral cover (n=615). The greatest perceived threats were: invasive species (n=606); water pollution (n=234); and unsustainable fishing (n=200). Areas of important reef characteristics, perceived threats to reefs, and perceived recovery potential were plotted to identify areas requiring critical management attention. The authors found that perceptions of healthy reef conditions outnumbered perceptions of reef threats for nine of the ten most familiar coral reefs; the most frequent activity type within the coral reefs was tourism diving; and for the most familiar coral reefs, the divers perceived a high recovery potential. Given the novelty of participatory mapping methods to assess coral reefs, the strengths and weaknesses of the method is evaluated. The authors further propose a management typology for categorizing reef areas to inform their future management. In the absence of primary data, or, as a supplement to underwater surveys and remotely-sensed data on reef condition, participatory mapping can provide a cost-effective means for assessing coral reef conditions while identifying place-specific reef locations requiring management attention. 相似文献
6.
P Thoya S Pérez-Jorge GM Okemwa H Mwamlavya A Tuda N Wambiji 《African Journal of Marine Science》2020,42(1):23-33
Ringnet fishing began in the early 20th century and is practised worldwide, mainly to target nearshore pelagic species. The method was introduced to Kenya’s coastal waters by migrant fishers from Tanzania. However, the impacts of this fishing gear remain poorly assessed. We assessed the spatial distribution of ringnet fishing effort and its possible effects on ecosystem components, such as coral reefs, marine megafauna and marine protected areas, on the south coast of Kenya. We tracked 89 ringnet fishing trips made from December 2015 to January 2016 and used spatial multicriteria analysis to determine hotspots of possible environmental risks. The results showed that habitat type and bathymetric profile influenced the spatial distribution of ringnet fishing effort. Mixed seagrass and coral habitats had the highest concentration of the effort. Most of the habitats in the study area were moderately exposed to the impacts of the ringnet fishery. The study identifies high-risk areas that require spatial measures to minimise possible environmental risks of the gear both to habitats and to endangered sea turtles. 相似文献
7.
SA Mwachireya M Carreiro-Silva BE Hartwick TR McClanahan 《African Journal of Marine Science》2018,40(1):25-42
Microbioerosion rates and microbioeroder community structure were studied in four Kenyan protected coral-reef lagoons using shell fragments of Tridacna giant clams to determine their response to the influence of terrestrial run-off. Fourteen different microbioeroder traces from seven cyanobacteria, three green algae and four fungi species were identified. The river discharge-impacted reef and ‘pristine’ reef showed similar composition but higher microbioeroder abundance and total cyanobacteria- and chlorophyte-bioeroded areas when compared with the other study reefs. Cyanobacteria dominated during the north-east monsoon (NEM) relative to the south-east monsoon (SEM) season, with algae and cyanobacteria being major microbioeroders in the river-impacted and pristine reefs. The rate of microbioerosion varied between 4.3 g CaCO3 m?2 y?1 (SEM) and 134.7 g CaCO3 m?2 y?1 (NEM), and was highest in the river-impacted reef (127.6 g CaCO3 m?2 y?1), which was almost double that in the pristine reef (69.5 g CaCO3 m?2 y?1) and the mangrove-fringed reef (56.2 g CaCO3 m?2 y?1). The microbioerosion rates measured in this study may not be high enough to cause concern with regard to the health and net carbonate production of Kenya’s coral reefs. Nevertheless, predicted increases in the frequency and severity of stresses related to global climate change (e.g. increased sea surface temperature, acidification), as well as interactions with local disturbances and their influence on bioerosion, may be increasingly important in the future. 相似文献
8.
为了解西沙群岛珊瑚礁海域浮游动物的群落特征, 于2015年5月末至7月初在西沙群岛8个岛礁(七连屿、永兴岛和东岛3个岛屿以及浪花礁、盘石屿、玉琢礁、华光礁和北礁5个环礁)进行了浮游动物采样, 分析了浮游动物的多样性、丰度和群落结构特征, 并比较了5个环礁潟湖内和向海礁坡区浮游动物群落组成的差异。调查海域共鉴定浮游动物180种(包括浮游幼虫13个类群), 其中桡足类最多, 达83种, 其次是水母类(38种)、浮游软体类(14种)、毛颚类(11种)和浮游被囊类(7种); 浮游动物平均丰度为256.4±117.8个·m-3, 桡足类占总丰度的51.08%, 其次是浮游幼虫(16.30%)、浮游被囊类(13.22%)和毛颚类(7.70%)。浮游动物种数、多样性和均匀度指数、丰度在岛屿和环礁之间以及环礁的潟湖区和向海礁坡区均存在差异; 浮游动物多样性和丰度在东岛、玉琢礁和华光礁较高, 而在七连屿和北礁较低; 5个环礁向海礁坡区的浮游动物多样性和丰度皆高于潟湖区的。多元统计分析结果表明调查岛礁的浮游动物可划分两个聚群(相似水平85%); 岛屿近岸及环礁的潟湖群落(Ⅰ)和岛屿远岸及环礁的向海礁坡群落(Ⅱ); 两个聚群浮游动物组成差异较显著(r=0.832, p<0.001); 前者的种数、多样性指数、总丰度和主要浮游动物类群如桡足类、毛颚类和浮游幼虫的丰度显著低于后者。环礁潟湖区和向海礁坡区的空间异质性和生态环境差异可能是导致浮游动物群落结构呈现不同特征的主要因素。 相似文献
9.
Effective conservation requires knowledge of the effects of habitat on distribution and abundance of organisms. Although the structure of coral reef fish assemblages is strongly correlated with attributes of reef structure, data relating reef types to fish assemblages are scarce. In this study we describe the influence of gross habitat characteristics and seasonality on coral reef fish assemblages of fringing and patch reefs in Kenya. Results showed that total fish abundance was not significantly different between the reefs; however, the fringing reef had higher species diversity during both the northeast (42 spp.) and southeast (36 spp.) monsoon seasons when compared to the patch reef. The more fished species (e.g. Siganus sutor and Lethrinus mahsena) were more abundant on the patch reef in both seasons. Statistical analysis indicated common species between the reefs were more abundant on the fringing reef. Seasons affected abundance of the more vagile species (S. sutor), whereas the reef‐attached sky emperor, L. mahsena was affected more by reef type than by seasons. No significant interaction effects of habitat and seasons were found, indicating independence of habitat and environmental variability in affecting fish assemblages on the reefs. Smaller sized fish dominated the fringing reef more than the patch reef, whereas the skewness index (Sk) indicated a normal‐sized frequency distribution on the patch reef. Trophic structure of the fishes varied more within than between reefs, whereas fish assemblage structure was affected more by seasons on the fringing reef. These results suggest that conservation measures such as marine protected area (MPA) design and setting should consider effects of reef morphology and environmental variability on coral‐reef fish assemblage structure. 相似文献
10.
《Marine Policy》2017
Marine management has typically prioritised natural science methodological traditions as an evidence base for decision-making; yet better integration of social science methods are increasingly shown to provide a more comprehensive picture to base management decisions. Specifically, perceptions-based assessments are gaining support, as they can provide efficient and holistic evaluation regarding management issues. This study focuses on coral reefs because they are particularly threatened ecosystems, due to their ecological complexity, socio-economic importance, and the range of environmental drivers that impact them. Research has largely concentrated on assessing proximate threats to coral reefs. Less attention has been given to distal drivers, such as socio-economic and governance factors. A common understanding of threats related to coral reef degradation is critical for integrated management that takes account of peoples’ concerns. This study compares perceptions of drivers of reef health among stakeholders (n = 110) across different sectors and governance levels, in four Caribbean countries. Interview data identified 37 proximate and 136 distal drivers, categorised into 27 themes. Five sub-groups of themes connecting proximate and distal drivers were identified. Perceptions of two of these narratives, relating to ‘fishing and socioeconomic issues’ and ‘reef management and coastal development’, differed among respondents from different countries and sectors respectively. However, the findings highlight a shared perception of many themes, with 18 of the 27 (67%) mentioned by > 25% of respondents. This paper highlights the application of perceptions data for marine management, demonstrating how knowledge of proximate and distal drivers can be applied to identify important issues at different context-specific scales. 相似文献
11.
南海珊瑚礁地貌模型研究 总被引：8，自引：1，他引：7
近200a前Darwin于1832-1836年间环球考察热带海洋珊瑚礁后,首次建立了珊瑚礁地貌模型并论述其形成机制,该模型总体形态呈全部或部分被上截了顶部的锥形,本文简称为"上截锥型"。此后历经几代学者的研究,都继承了他的珊瑚礁地貌模型。对南海珊瑚礁地貌模型的研究,近年有研究描绘为另外一种模型,该模型的特点是礁外坡为内凹形,礁体形态呈蘑菇状,本文称为"蘑菇型"。本文根据许多南海珊瑚礁地形实测资料和地貌学研究文献,确认南海珊瑚礁地貌模型应为上截锥型,"蘑菇型"珊瑚礁地貌模型并不符合珊瑚礁形成演化规律,在自然界内不存在。 相似文献
12.
《Marine Policy》2013
Conflict surrounding commercial fisheries is a common phenomenon when diverse stakeholders are involved. Harvesting reef fish for the global ornamental fish trade has provoked conflict since the late 1970s in the State of Hawaii. Two decades later the state of Hawaii established a network of marine protected areas (MPAs) on the west coast of the island of Hawaii (“West Hawaii”) to protect and enhance the fish resources and alleviate conflict between stakeholders, principally between commercial dive tour operators and aquarium fishers. The perceptions held by these stakeholders on West Hawaii and Maui were evaluated to understand how MPAs influenced conflict dimensions, as the former location had a well-established MPA network designed to alleviate conflict, while the latter did not. This was accomplished by analyzing the following questions: (1) perceptions about the effectiveness of MPAs to alleviate conflict and enhance reef fish; (2) perceived group encounters and threats to coral reefs; (3) willingness to encourage fishing; and (4) value orientations toward the aquarium fish trade. The results indicate the MPAs in West Hawaii were moderately effective for alleviating conflict, encounters between stakeholders occurred on both islands, dive operators strongly opposed commercial fishing and perceived aquarium fishing as a serious threat to the coral reef ecosystem, and polarized value orientations toward the aquarium fish trade confirms pervasive social values conflict. The conflict between these groups was also asymmetrical. MPAs are inadequate for resolving long term conflict between groups who hold highly dissimilar value orientations toward the use of marine resources. Future marine spatial planning and MPA setting processes should include stakeholder value and conflict assessments to avoid and manage tensions between competing user groups. 相似文献
13.
Networks of no-take marine reserves (NTMRs) are widely used for managing marine resources. Because they restrict fishing, managers need to monitor reserves to reassure stakeholders that they are achieving the intended results. In 2004, the Great Barrier Reef (GBR) Marine Park was rezoned and the area of NTMRs was greatly increased. Using manta tow we assessed the effectiveness of the new NTMRs in conserving coral trout (Plectropomus and Variola spp.), the principle targets of the GBR reef line fishery. Over a six year period, we sampled regional groups of matched pairs of similar reefs, ones closed to fishing under the rezoning and ones that remained open. Coral trout populations were significantly higher in NTMRs. While coral trout populations declined on reefs open to fishing, stocks were maintained in NTMRs, highlighting the ongoing benefits of marine reserves. 相似文献
14.
为研究方型人工鱼礁体水动力特性受礁体布设间距变化的影响,通过物模实验实测了开口比为0.3的方形开口双礁体在布设间距为1.0L、2.0L时周围特征点的流速及礁体受力,并利用Fluent软件模拟了双礁体在布设间距为0.5L、1.0L、2.0L、4.0L时的水动力场,通过分析得到了礁体上升流特性参数、阻力系数随布设间距的变化情况。研究结果表明:数值模拟结果与实验结果吻合较好,本文数值模拟方法是可行的;模拟工况下,随着布设间距的增加,双礁体产生的上升流区体积逐渐减小,阻力系数逐渐增大,流场效应较好的布设间距为0.5L、1.0L、2.0L。研究结果可为礁区布局方案的确定提供参考。 相似文献
15.
Coral reefs are vital to the livelihood of coastal communities in Quintana Roo, México and the preservation of these ecosystems relies on the establishment of protected areas. Education should be one of the most important management tools in coral reef preservation. Surveys were made among primary and secondary school students of Quintana Roo to determine the level of education regarding coral reefs and their importance. Students had little awareness about reefs. Coverage of coral reef issues is insufficient in school curricula and information media. Many students will leave school and become users of the reef with little understanding of it and of the consequences of exploitation of the reef. Creation of marine parks has not increased education and public awareness. There is an immediate need to establish appropriate and continuously available educational programs in order to preserve coral reefs. Education should encourage codes of behavior and community support to management issues. 相似文献
16.
This work aims to compile knowledge on ecologically rich habitats that deserve special protection in the Mediterranean high seas. Many marine ecosystems are currently threatened by fishing activities, such as bottom trawling, gillnets and demersal and pelagic long-lines. Especially vulnerable are areas described as either sensitive habitats or essential fish habitats. Among these we highlight the associations of sessile organisms, such as cold coral reefs, mostly detected on continental slopes, seamounts and on the walls of submarine canyons, and those areas considered as hot spots of diversity and habitat of vulnerable fauna, like cold seeps, hydrothermal vents and submarine canyons. Essential habitats for pelagic species are defined by oceanographic features like productive areas associated with upwelling, and in the Mediterranean the spawning areas and migratory routes of bluefin tuna, swordfish, and albacore are of high conservation interest. We propose that in a context of difficult fisheries management in Mediterranean international waters, or high seas, these vulnerable habitats should be protected through the establishment of a web of Marine Protected Areas coordinated by all the involved countries and controlled by strict surveillance. 相似文献
17.
Limiting accessibility to a fishing area can reduce fishing effort effectively and may therefore promote local recovery of depleted stocks. In January 2002, beach driving was banned in South Africa, thereby reducing angler access to large areas of the coastline, particularly in less-developed areas. In November 2001 a project had been established in the St Lucia Marine Reserve, on the east coast of South Africa, to compare surf-zone fish populations inside a no-take sanctuary zone with those in an adjacent exploited area. Subsequent to the ban, the aim of the project was adapted such that surf-zone fish populations were monitored for potential recovery in what had been the exploited area, located to the north of Cape Vidal, which anglers could no longer access easily, because of the prohibition on beach driving. Standardised research fishing was conducted at two sites in the previously exploited area and two sites in the no-take sanctuary. Conventional stock-status indicators showed evidence of recovery in the four most common species caught in the previously exploited area, in terms of both abundance and biomass. Generalised additive mixed models were used to account for the influence of targeting specific species; however, subtle differences in habitat between the sampling sites, improved angling skill over time, variability in recruitment, and differential species-specific responses complicated interpretation of results. The implications of the findings are discussed in terms of the future monitoring and management of marine protected areas both within the St Lucia Marine Reserve and farther afield. 相似文献
18.
珊瑚藻是珊瑚礁生态系统中重要的功能性群体。2010年通过水肺潜水分析了三亚珊瑚礁区的珊瑚藻种类组成和丰度, 以及群落空间特征与环境因子的关系。共鉴定出3科10属25种珊瑚藻, 其中珊瑚藻科占优势地位。三亚珊瑚礁区的珊瑚藻优势种分别为叉节藻Amphiroa ephedraea、拟中叶藻Mesophyllum simulans、串胞新角石藻Neogoniolithon fosliei、中叶藻M. mesomorphum、圆锥呼叶藻Pneophyllum conicum、孔石藻Porolithon onkodes和布氏水石藻Hydrolithon boergesenii。基于多元统计的分析结果, 将调查采样站位分为近岸型和离岸型2个主要集群, 其中近岸型的珊瑚藻种类以浊度、沉积速率(0~63μm)和悬浮物耐受种类为主, 离岸型则以光依赖-沉积物敏感种类为主。以珊瑚藻种类组成和丰度为基础的群落相似性分析结果表明, 其空间变异处于显著性水平。生物与非生物变量的相关分析结果表明, 最佳两变量组合(浊度和盐度)显著影响三亚珊瑚礁区2种类型调查站位中的珊瑚藻集合。在同一个研究站位, 因受干扰程度不同, 深水处的珊瑚藻的覆盖率比浅水处高。分析结果表明, 在三亚独特的珊瑚礁区中, 自然或人为的物理干扰因素都对调节珊瑚藻群落结构非常重要。 相似文献
19.
《Marine Policy》2014
In any given region, there are multiple options for terrestrial protected area networks that achieve goals for conservation of terrestrial biodiversity and ecosystem values. When deciding on the location of terrestrial protected areas, planners typically focus only on terrestrial conservation goals, ignoring potential linked benefits to marine ecosystems. These benefits include maintenance of downstream water quality, as forest protection can prevent changes in amount and composition of river runoff that negatively impacts coral reefs. This study aims to determine the benefit of different terrestrial reserve networks to the condition of coral reefs adjacent to the main islands of Fiji to support the work of Fiji's Protected Area Committee in expanding the national protected area estate through integrated land–sea planning. Options for terrestrial protected area networks were designed using six approaches, where the primary objective of each approach was to either achieve terrestrial conservation goals (e.g., represent 40% of each vegetation type) or maximize benefits to coral reefs by minimizing potential for land-based runoff. When achieving terrestrial conservation goals was the primary objective, the potential benefits to coral reef condition were 7.7–10.4% greater than benefits from the existing network of protected areas. When benefiting reefs was the primary objective, benefits to coral reefs were 1.1–2.8 times greater per unit area than networks designed to only achieve terrestrial conservation goals, but 31–44% of the terrestrial conservation goals were not achieved. These results are already being used by Fiji's Protected Area Committee to modify the boundaries of existing priority places to deliver outcomes that better meet terrestrial conservation goals while offering greater benefits to coral reef condition through prevention of run-off. 相似文献
20.
《Ocean & Coastal Management》2007,50(1-2):67-83
The 1992 Convention on Biological Diversity has set ambitious targets for the establishment and management of protected areas. For the oceans, the overall aim is to establish, by 2012, an effectively managed, representative, global system of marine protected areas (MPAs) covering 10% of all marine ecological regions, comprising both multiple use areas and strictly protected areas. An analysis of data for three countries in Eastern Africa, where considerable efforts to promote MPAs by many agencies have been made over the past decade, shows that rapid progress has been made towards achieving this target. Since the first MPAs were established in the 1960s and 1970s, 8.7% of the continental shelf in Kenya, 8.1% in Tanzania and 4.0% in Mozambique has been designated, with the size of recently protected sites markedly larger than earlier sites. Commitments to expand the MPA networks in these countries would, if implemented, largely achieve the 10% coverage target. The location of existing marine protected areas shows good correlation with known sites of high species diversity; and coral reefs and Important Bird Areas are well represented. Management effectiveness of MPAs is also improving. However, there are major constraints to meeting the MPA target in these countries. Many habitats and species are not yet fully represented, the area closed to fishing is less than the recommended 20–30%, and capacity building is needed to improve many aspects of management. Furthermore, despite considerable investment in monitoring of coral reefs and other coastal habitats, the data available do not show clearly whether biodiversity and socio-economic objectives are being met. Although East African countries need to be congratulated for their vision, the results thus far indicate the urgency of both improving monitoring systems for measuring progress towards the targets, and also taking further steps to expand and improve management of existing MPAs. 相似文献