建设人工藻礁的意义

从人工藻礁在藻场修复中的作用以及其建设过程可以利用陆地上废弃物2个方面论述了建设人工藻礁的意义。     

Population density estimation of southern stingrays Dasyatis americana on a Caribbean atoll using distance sampling

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Impacts of a Hawaiian marine protected area network on the abundance and fishery sustainability of the yellow tang, Zebrasoma flavescens

Marine protected areas can enhance fish stocks within their boundaries, but the circumstances in which they might also supplement stocks or enhance fisheries outside their boundaries are less clear. Using visual survey and fishery data, we assess the impacts of increasing fishing effort, and of the establishment in Hawaii of a network of areas closed to aquarium fishing, on the prime-target species, yellow tang (Zebrasoma flavescens), and draw conclusions about MPA impacts on long-term fishery sustainability. Between 1999, when 27.8% of the coastline was closed to collecting, and 2007, the number of active fishers and total catch of yellow tang doubled. Prior to MPA establishment, yellow tang densities were similar at sites open to fishing and those slated for closure. By 2007, closed areas had five times the density of prime targeted sized fish (5-10 cm), and 48% higher density of adults than open areas. Densities of adults in ‘boundary’ areas (open areas <1 km from nearest MPA boundary) were significantly higher than in open areas far from MPA boundaries, which was indicative of spillover at that scale. Given the long life-span of yellow tang (>40 years) relative to the duration of protection and the increasing intensity of fishing, the likelihood is that protected areas will become increasingly important sources for the adult fishes which will sustain stocks and the fishery over the longer term.     

Thresholds and multiple scale interaction of environment, resource use, and market proximity on reef fishery resources in the Solomon Islands

Reef fish are critical in maintaining the ecological function of coral reefs and providing food security for coastal communities in developing countries. Reef fishery stocks are under increasing threat from factors such as climate-related habitat degradation, land use practices, and resource extraction related to human population growth, direct consumption and increasing connectivity between the in situ fishery and fish markets. This study investigates how reef fish stocks are related to environmental, localised resource use and market proximity indicators across 51 sites in the Solomon Islands. Hard coral cover is the best indicator of total target fishery biomass, with cover of less than around 31% associated with significantly less biomass than sites with higher coral cover. Direct resource use indicators such as fish consumption and fish sale pressure were poor predictors of target fish biomass. Distance of the fishery resource from community, provincial sub-station, provincial capital and national capital are all significantly and positively correlated with biomass for four key fishery families: Acanthuridae (surgeonfish), Scaridae (parrotfish), Lethrinidae (emperor), Lutjanidae (snapper). Multiple spatial scale relationships are evident between market proximity indicators and Lutjanidae and Scaridae families. Thus, while pooled target fishery biomass is constrained by environment, analysis at fishery family resolution reveals the effects of anthropogenic impact through market proximity on constraining fishery biomass distribution in the Solomon Islands. This study highlights the need for reef fishery managers and conservation practitioners to focus attention on proximity of resources to markets to sustain the ecological health of reef dominated ecosystems.     

天津大神堂海洋特别保护区海域浮游植物多样性研究

通过2012年4月和9月及2013年5月和9月天津大神堂海洋特别保护区海域9个站位定点采样调查,分析了其浮游植物的种类多样性和种群动态.结果表明,该海域共鉴定浮游植物4门20属49种,主要为近岸低盐性种类并伴有少量外海高盐性种类.其中,硅藻门44种,占90％;金藻门1种,占2％;蓝藻门1种,占2％;甲藻门3种,占6％.优势种类有硅藻门的威氏角毛藻（Chaetoceros weissflogii）、星脐圆筛藻（Coscinodiscus asteromphalus）、虹彩圆筛藻（Cos.oculus-iridis）、苏氏圆筛藻（Cos.thorii）、尖刺菱形藻（Nitzschia pungens）、美丽曲舟藻（Pleurosigma formosum）、柔弱根管藻（Rhizosolenia delicatula）、中肋骨条藻（Skeletonema costatum）和甲藻门的夜光藻（Noctiluca scintillans）,其中赤潮种类中肋骨条藻一直居于优势地位.该海域浮游植物物种丰度、多样性指数、均匀度指数均较低,说明种群结构不稳定,总体呈现中度污染状态.     

Latitudinal shifts in coral reef fishes: why some species do and others do not shift

Climate change is resulting in rapid poleward shifts in the geographical distribution of many tropical fish species, but it is equally apparent that some fishes are failing to exhibit expected shifts in their geographical distribution. There is still little understanding of the species‐specific traits that may constrain or promote successful establishment of populations in temperate regions. We review the factors likely to affect population establishment, including larval supply, settlement and post‐settlement processes. In addition, we conduct meta‐analyses on existing and new data to examine relationships between species‐specific traits and vagrancy. We show that tropical vagrant species are more likely to originate from high‐latitude populations, while at the demographic level, tropical fish species with large body size, high swimming ability, large size at settlement and pelagic spawning behaviour are more likely to show successful settlement into temperate habitats. We also show that both habitat and food limitation at settlement and within juvenile stages may constrain tropical vagrant communities to those species with medium to low reliance on coral resources.     

浙江中北部沿海人工渔礁拟投放区夏季近底层水生游泳动物组成分析

通过对浙江中北部海区13个人工渔礁拟投放点的拖网调查,从而获得了各拟投放点的水生游泳动物组成数据并进行分析,研究结果表明：在浙江中北部人工渔礁拟投放区海域共捕获水生游泳动物50种,分别隶属于3门,3纲,14目,34科。其中,鱼类26种,虾蟹类20种,头足类3种,其他甲壳类1种。各类群的资源重量密度指数和资源尾数密度指数的最大值分别出现在P1号站和P7号站。水生游泳动物的优势种为中国毛虾Acetes chinensis、中华管鞭虾Solenocera crassicor-nis、矛尾鰕虎鱼Chaeturichthys stigmatias、口虾蛄Oratosquilla oratoria、须赤虾Metapenaeopsis barbata、葛氏长臂虾Palaemon gravieri,常见种为双斑蟳Charybdis bimaculata、鹰爪虾Trachypenaeus curvirostris、狼牙鳗鰕虎鱼Taenioides rubicundus、哈氏仿对虾Parapenaeopsis hardwickii、长蛸Octopus variabilis、日本蟳Charybdis japonica、皮氏叫姑鱼Johnius belengerii、带鱼Trichiurus japonicus、前肛鳗Dysomma anguillare、剑尖枪乌贼Loligo edulis、刺鲳Psenopsis anomala、小黄鱼Larimichthys poly-actis、细巧仿对虾Parapenaeopsis tenella等。     

长江口滩涂电杆礁生态修复区栖息地含水量分析

近年来长江口浦东机场外进行了滩涂围垦,根据浦东机场围垦区外侧滩涂的特殊性,选用电杆礁生态修复技术进行滩涂生态修复。结果显示在电杆礁修复实施后,其基部可形成小水体,小水体体积与电杆礁地上高度具有相关性(P=0. 035),且修复区内电杆礁基部沉积物的含水量为45. 62%。通过对修复区内外沉积土样含水量的比较分析,显示修复时间影响沉积土样的含水量,修复时间长(180 d)的区域0 m处的含水量(48. 41%)高于修复时间短(90 d)的区域0 m处的含水量(40. 73%);位于修复区近岸侧的含水量(50. 56%)高于远岸侧含水量(38. 22%);垂直于海岸线向修复区外延伸的样点(纵向样点)的含水量(48. 24%)高于平行海岸线向修复区外延伸的样点(横向样点)的含水量(37. 29%)。综上所述,电杆礁生态修复技术能够提升修复区滩涂栖息地含水量。     

Behaviour of recreational spearfishers and its impacts on corals

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Community biomass and life history benchmarks for coral reef fisheries

The status of fisheries requires establishing and evaluating benchmarks derived from unfished ecosystems. Habitats, environmental conditions, properties of the fish communities and management systems could potentially influence the variability surrounding benchmarks. Consequently, eighteen variables including habitat, number of species, life histories, thermal and productivity environments were tested for influences on reef fish biomass in 62 reefs within old high compliance closures along the east African coastline. Biomass and weighted life history characteristics were classified and described for total, fishable, target and non‐target groups. Benchmark biomass fell within a 95% confidence interval of ~1,030–1,250 kg/ha and equally distributed among target and non‐target groups. While some relationships were statistically significant, most were weak, poorly sampled (ocean exposed reefs), had uncertain relationships with biomass (number of species), or the explained variation was bounded within the above confidence intervals (habitat and environment). Therefore, a regional unfished biomass benchmark (B₀) of 1,150 and 560 kg/ha is recommended for total and target biomasses, respectively. Weighted life history metrics indicate that the target had slower life histories than the non‐target fish communities. Consequently, they will be fished unsustainably if yield recommendations are derived from the total, resilient or non‐target fish life history metrics. The intrinsic rates of increase (r) and target categorization of biomass were the most influential metrics in estimating yields.