安徽菜子湖大型底栖动物的群落结构特征

近年来,长江中下游迅速发展的淡水渔业对湖泊湿地产生严重扰动,湖泊生态系统的结构和功能受到影响。为揭示大型底栖动物群落对湖泊扰动的响应,对安徽菜子湖群不同养殖程度的白兔湖、嬉子湖和菜子湖3个湖区进行了大型底栖动物周年定量调查。全湖设置49个样点,调查7次。共采集到大型底栖动物34属39种,优势种为摇蚊(Tendipes sp.)、苏氏尾鳃蚓(Branchiura sowerbyi)、长角涵螺(Alocinma longicornis)。大型底栖动物密度为(55.20±76.25) 个/m²,生物量为(19.56±65.37) g/m²,其中白兔湖、菜子湖、嬉子湖密度分别为(63.43±52.76)、(36.44±34.49)和(79.77±118.90) 个/m²,生物量分别为(17.48±28.24)、(21.70±39.44)和(4.94±18.46) g/m²。嬉子湖的节肢动物密度和生物量均显著大于白兔湖和菜子湖(P＜0.01),而白兔湖和菜子湖的软体动物密度和生物量均显著大于嬉子湖(P＜0.01)。聚类分析表明,白兔湖和菜子湖的大型底栖动物的群落结构相似性较高,但与嬉子湖养殖区的相似性较低。白兔湖和菜子湖大型底栖动物的Shannon-Wiener指数分别为2.25、1.71,嬉子湖仅为1.44。与2001年的资料相比,大型底栖动物的优势种发生了改变,群落多样性显著降低。水产养殖、修建堤坝等人为干扰已经对菜子湖群大型底栖动物群落结构产生了较大的影响,发展可持续渔业将是湖泊生态系统保护的重要途径。     

洋山港潮间带大型底栖动物群落结构及多样性

2009-2010年在洋山港海域大洋山岛和圣姑礁进行四个季度潮间带大型底栖动物生态学研究。共采集到大型底栖动物61种,以广布种为主,部分为河口低盐种,其中软体动物22种,环节动物16种,节肢动物12种,苔藓动物5种,腔肠动物4种,星虫动物和棘皮动物各1种。优势种为短滨螺(Littorina brevicula)、多齿围沙蚕(Perinereis nuntia)、日本笠藤壶(Tetraclita japonica)、齿纹蜒螺(Nerita yoldii)和特异大权蟹(Macromedaeus distinguendus)。丰度和生物量在不同季节明显不同(P<0.05):丰度的最高值出现在春季,为(3204.9±837.84)个/m²,最低值出现在秋季,仅为(2213.2±731.27)个/m²;生物量的最高值则出现在夏季(2233.2±1493.42)g/m²,冬季最少,仅为(819.95±484.80) g/m²。大洋山岛和圣姑礁的丰度和生物量具有较大差异(P<0.05):年均丰度以大洋山断面较高,为(3090±742.74)个/m²,圣姑礁断面较低,为(2133±372.51)个/m²;而年均生物量则以圣姑礁断面较高,为(1711.1±1180.76) g/m²,大洋山断面较低,仅为(1028.5±627.61) g/m²。运用ABC曲线、等级聚类和MDS对大型底栖动物群落结构分析发现:大洋山潮带间大型底栖动物群落尚未受到干扰或干扰较轻,群落结构相对稳定;而圣姑礁断面的潮间带大型底栖动物群落受到了中度的干扰,群落结构稳定性下降。与15年前的研究相比,圣姑礁大型底栖动物的密度和生物量均有大幅度的降低,这与洋山港海域盐度的升高、生态环境变化和人为干扰强度增加等有关。     

乐清湾潮间带大型底栖动物群落分布格局及其对人类活动的响应

于2006年9月和2007年5月对乐清湾5条潮间带断面进行了大型底栖动物调查。 共鉴定出大型底栖动物113种, 其中软体动物40种, 多毛类25种, 甲壳动物24种, 棘皮动物9种, 其它动物15种。从季节来看, 物种数秋季(81种)高于春季(68种),但平均生物量和平均栖息密度春季(分别为(91.90±59.14) g/m²和(1541±1261.41)个/m²)明显高于秋季(29.20±22.20)g/m²和(201±52.97)个/m²);春季以焦河蓝蛤 幼体、彩虹明樱蛤 、婆罗囊螺 、绯拟沼螺 为主要优势种,而秋季以短拟沼螺 、彩虹明樱蛤、淡水泥蟹 、巢沙蚕 为主要优势种,说明乐清湾大型底栖动物群落特征随着季节有着较大的变化。各断面的Shannon-Winner指数(H')为2.34-3.31,平均为2.85±0.35;Margalef's species richness 指数(d)为3.02-6.42,平均为4.29±1.10;Pielou's evenness 指数(J')为0.46-0.73,平均为0.62±0.09。运用ABC曲线、等级聚类和MDS对大型底栖动物群落结构分析发现,群落结构已受到中度干扰,稳定性差。与以往历史资料相比,乐清湾大型底栖动物向次生型群落转化,原因可能与过度采捕、生境恶化、海岸工程以及围塘养殖等人类活动的影响有关。     

长江口互花米草生长区大型底栖动物的群落特征

2005年对长江口潮滩湿地互花米草（Spartina alterniflora）生长区不同季节大型底栖动物群落特征的研究表明：长江口互花米草生长区的大型底栖动物有21种，其中甲壳纲10种、多毛纲5种、腹足纲5种、辨鳃纲1种。主要种类有拟沼螺（Assiminea sp.）、背蚓虫（Notomastus latericeus）、尖锥拟蟹守螺（Cerithidea largillierli）、中国绿螂（Glauconome chinensis）、钩虾（Gammaridae sp.）等。食性功能群均以碎屑食者和植食者为主。大型底栖动物平均栖息密度为(650.5±719.2)个/m²，标准误主要是由于北湖的拟沼螺密度很大。栖息密度从大到小的顺序为沿河口梯度从内到外分布的北湖边滩、崇明东滩、金山卫边滩。大型底栖动物群落分布不均匀，沿河口梯度变化存在明显的空间差异。栖息密度和物种多样性在夏季最高，冬季最低。大型底栖动物平均生物量为(20.8±6.1)g/m²，季相变化为夏季>秋季>春季>冬季。BIO-ENV分析表明沉积物粒径和盐沼高度是大型底栖动物群落特征的主要影响因素。不同研究结果的差异除了时空因素外可能与互花米草的种群动态有关。加强不同时间尺度的研究有助于正确评价互花米草对大型底栖动物的影响。     

山地河流浅滩深潭生境大型底栖动物群落比较研究——以重庆开县东河为例

浅滩和深潭是山地河流中常见的河流生境结构。2011年7月,在重庆开县东河上游双河口-杉木桥河段,选择21个浅滩和深潭,调查大型底栖动物,研究影响不同生境中底栖动物组成、分布和多样性的生态机理。结果表明:调查河段浅滩和深潭中大型底栖动物分别为31种和24种,密度分别为450.62 个/m²和86.24 个/m²,生物量分别为2.88 g/m²和0.55 g/m²。浅滩有指示种11种,即纹石蛾(Hydropsyche sp.)、假蜉(Iron sp.)、假二翅蜉(Pseudocloeon sp.)、舌石蛾(Glossosoma sp.)、高翔蜉(Epeorus sp.1)、背刺蜉(Notacanthurus sp.)、Heterocloeon sp、锯形蜉(Serratella sp.)、朝大蚊(Antocha sp.)、等蜉(Isonychia sp.)、溪颏蜉(Rhithrogena sp.)。深潭指示种仅蜉蝣(Ephemera sp.)和黑大蚊(Hexatoma sp.)两种。刮食者为两类生境的优势功能摄食类群。浅滩中滤食者和刮食者比例显著高于深潭,而收集者和捕食者显著低于深潭。两类生境中大型底栖动物群落结构差异显著。浅滩中大型底栖动物的密度、生物量、丰富度指数、Shannon-Wiener 指数、改进的Shannon-Wiener指数均明显高于深潭。受地貌形态、水力特征和冲淤变化规律影响的生境稳定性和异质性差异是导致大型底栖动物群落差异的主要原因。     

泉州湾蟳埔潮间带大型底栖动物群落的时空分布

为了比较泉州湾蟳埔潮间带沙滩、互花米草滩和牡蛎石泥滩3种生境(3个潮层)的大型底栖动物群落,2011年4月至2012年1月对3种生境的大型底栖动物进行了季度定量取样。在3种生境共获得85种大型底栖动物,其中环节动物39种,软体动物20种,节肢动物21种,刺胞动物、扁形动物、纽虫动物、星虫动物和脊索动物各1种。多维标度排序(MDS)分析表明,春季和冬季泉州湾蟳埔潮间带3种生境的大型底栖动物群落相似性较低;夏季和秋季互花米草滩与牡蛎石泥滩的大型底栖动物群落相似性较高,而与沙滩的大型底栖动物群落相似性较低。沙滩大型底栖动物群落的季节变化较明显,其次是牡蛎石泥滩,而互花米草滩大型底栖动物群落的季节变化较不明显。大型底栖动物栖息密度和生物量随着潮层降低而增加。单变量双因素方差分析(Two-way ANOVA)表明,不同生境之间的大型底栖动物物种数、栖息密度、多样性指数、均匀度指数和丰度指数有显著差异,但生物量无显著差异,这是因为沙滩的物种数较少,栖息密度较低,但优势种弧边招潮蟹(Uca arcuata)个体较大,互花米草滩和牡蛎石泥滩的优势种为加州中蚓虫(Mediomastus californiensis),个体相对弧边招潮蟹小。不同季节之间大型底栖动物物种数、栖息密度、生物量和丰度指数有显著差异,但多样性指数和均匀度指数元显著差异,这是因为沙滩物种数少,但个体分布比较均匀,而互花米草滩和牡蛎石泥滩物种数较多,个体分布较不均匀。以上结果表明,潮汐、沉积物粒径和生境是影响潮间带大型底栖动物群落的主要因素。潮汐导致潮间带的空间异质性,空间异质性导致大型底栖动物群落的差异。     

瓯江口海域大型底栖动物分布及其与环境的关系

对瓯江口及邻近海域大型底栖动物进行了春（2006年5月）、冬（2007年1月）两季的调查,分析了研究区大型底栖动物的季节分布及其与环境的关系.结果表明：共鉴定出大型底栖动物65种,多毛类和软体动物是该海域大型底栖动物的主要类群;春季,小头虫的优势度最高,冬季,红带织纹螺的优势度最高;研究区大型底栖动物的种类分布为河口区＜邻近海域、冬季＜春季;该区大型底栖动物两季平均生物量和栖息密度分别为19.66 g·m^-2和131 ind·m^-2,春、冬季的密度差异显著,但生物量差异不显著;春冬两季研究区大型底栖动物的Shannon-Weiner指数差异显著,Pielou均匀度指数、Margalef种类丰富度指数和Simpson优势度指数的差异不显著.春季,温度和浮游植物是影响研究区大型底栖动物类群的主要环境因子,冬季的主要影响因子为总有机碳和溶解氧.     

椒江口滩涂大型底栖动物群落格局与多样性

为了解椒江口滩涂大型底栖动物群落格局与多样性, 揭示其对环境变化的响应规律, 作者于2007年10月、2008年1月、4月和7月在椒江口南岸和北岸潮间带, 沿河流到海洋方向共布设6条采样断面进行大型底栖动物调查。分析了大型底栖动物种类组成、栖息密度和生物量的时空变化特征, 在此基础上运用α, β和γ多样性测度方法对大型底栖动物多样性进行分析, 同时探讨了大型底栖动物群落结构对环境变化的响应方向及程度, 结果显示: (1) 6条断面共记录到大型底栖动物78种, 总种数随季节变化显著, 在空间上沿河流到海洋方向呈升高趋势; (2) 栖息密度的季节变化不显著(P=0.145>0.05), 但空间变化显著(P=0.017<0.05), 生物量的季节变化显著(P=0.012<0.05), 空间变化极显著(P=0.004<0.01); (3) β和γ多样性指数定量显示了椒江河口区域滩涂环境的多变性和大型底栖动物群落的多样性和更替性。     

洋山港海域码头人工潮间带大型底栖无脊椎动物群落变化

洋山港是世界第一大集装箱港，自2002年开始至2017年共完成四期工程建设，期间港口建设中形成了8 000余米的码头人工岸线，受港区一至四期工程的顺序建设、岛礁连接、围海造地和港口运营的远洋船舶停靠等影响，港口海域生态环境也逐步出现相应变化，导致包括潮间带大型底栖无脊椎动物在内的海洋生物群落均受到相应影响。本研究于2021和2022年(第四期工程建设后)在洋山港港区二号码头与港区海域大洋山码头人工潮间带采集了大型底栖无脊椎动物，并对其群落结构与特征进行分析，同时与2009和2010年(第四期工程建设初)的历史调查资料对比，分析了第四期工程建设以来洋山港海域码头人工潮间带大型底栖无脊椎动物的群落变化。结果显示，洋山港海域码头人工潮间带大型底栖无脊椎动物种类数量由第四期工程建设前的17种增加至第四期工程建设后的28种，其中软体动物由8种增加至15种，节肢动物由7种增加至9种，腔肠动物增加至3种，环节动物增加至1种；跨海区入侵种东方小藤壶(Chthamalus challengeri)消失，而纹藤壶(Amphibalanus amphitrite)重新出现并成为优势种；洋山港人工码头潮间带大型底栖无脊椎动物群落密度最高值由第四期工程建设初的(6 333.30 ± 1 495.49)ind/m²增加至(6 517.33 ± 119.67)ind/m²，生物量最高值由第四期工程建设初的(1 977.04 ± 281.87)g/m²增加至(3 724.69 ± 940.94)g/m²；洋山港人工码头潮间带群落生物多样性指数有所上升而大洋山人工码头下降显著。与洋山港第四期工程建设初相比，洋山港海域码头人工潮间带大型底栖无脊椎动物群落种类组成已经发生变化，群落生物多样性指数与丰度-生物量曲线(ABC曲线)分析结果均表明，目前洋山港海域生态环境处于中等污染水平。受港区运营影响，码头人工潮间带大型底栖无脊椎动物群落仍受到中等程度的干扰，群落结构不稳定。     

考洲洋人工种植红树林湿地大型底栖动物群落环境响应

2017年以来,广东省惠州市在考洲洋潮间带开展了大规模人工种植红树林生态修复工程,但考洲洋人工种植红树林湿地大型底栖动物群落的环境响应未见报道。根据2018-2019年四个季节在考洲洋盐洲大桥附近红树种植1-2年（X断面）和5-6年（Y断面）的两处湿地的大型底栖动物定量取样数据,分析了人工红树林湿地大型底栖动物的时空格局及其环境响应。方差分析表明,Y断面冬季的大型底栖动物群落的物种数、栖息密度、生物量、多样性指数（H''）和丰富度指数（d）,以及夏季的栖息密度均随潮高（海平面高程）降低而增加;而Y断面冬季的均匀度指数（J）、夏季的H''和J则是随潮高降低而减少。聚类（Cluster）和非度量多维尺度（nMDS）分析表明冬季和夏季X断面和Y断面大型底栖动物群落相似性较低,而春季和秋季X断面和Y断面大型底栖动物群落相似性较高。冬季和夏季最大潮高、潮差、大型底栖动物物种数、栖息密度、H''和d较春季和秋季的高。红树种植1-2年的X断面大型底栖动物物种数、H''和J低于种植5-6年的Y断面。上述结果证实潮汐和红树种植年限影响考洲洋红树林湿地大型底栖动物的群落结构,研究结果可为大型底栖动物多样性保护和生态修复提供基础资料。     

The composite trophic status index (TRIX) as a potential tool for the regulation of Turkish marine aquaculture as applied to the eastern Aegean coast (Izmir Bay)

This research examines the current water quality status of Izmir Bay, using the trophic index (TRIX) as a tool for the regulation of Turkish marine finfish aquaculture. In 2007, new legislation was enacted in Turkey related to the protection of coastal waters, especially those of enclosed bays and gulfs, from pollution by fish farming. However, the legislation does not apply to any other coastal zone stakeholders; for this reason the entire Izmir Bay was examined. Use of the composite trophic status index (TRIX) produced mean TRIX values of 3.6 for the aquaculture area (AA) and 2.5 for areas of the outer bay where no aquaculture takes place; this indicates ‘no risk of eutrophication’ as defined by Turkish law. In the inner Izmir Bay, there is a mean TRIX value of 4.3, which is above the threshold of four and typical for ‘high eutrophication risk’ areas, as expected because of heavy urbanization. The study then applied the UNTRIX indices adjusted to local conditions, revealing that both the inner bay and the aquaculture area (AA) can be classified as of ‘poor’ status whereas the outer bay can be defined as ‘good’. The UNTRIX‐based trophic classification is in good agreement with TRIX for both the outer and inner parts of the bay; however, there is no agreement regarding the classification of the aquaculture area.     

Bivalve aquaculture‐environment interactions in the context of climate change

Coastal embayments are at risk of impacts by climate change drivers such as ocean warming, sea level rise and alteration in precipitation regimes. The response of the ecosystem to these drivers is highly dependent on their magnitude of change, but also on physical characteristics such as bay morphology and river discharge, which play key roles in water residence time and hence estuarine functioning. These considerations are especially relevant for bivalve aquaculture sites, where the cultured biomass can alter ecosystem dynamics. The combination of climate change, physical and aquaculture drivers can result in synergistic/antagonistic and nonlinear processes. A spatially explicit model was constructed to explore effects of the physical environment (bay geomorphic type, freshwater inputs), climate change drivers (sea level, temperature, precipitation) and aquaculture (bivalve species, stock) on ecosystem functioning. A factorial design led to 336 scenarios (48 hydrodynamic × 7 management). Model outcomes suggest that the physical environment controls estuarine functioning given its influence on primary productivity (bottom‐up control dominated by riverine nutrients) and horizontal advection with the open ocean (dominated by bay geomorphic type). The intensity of bivalve aquaculture ultimately determines the bivalve–phytoplankton trophic interaction, which can range from a bottom‐up control triggered by ammonia excretion to a top‐down control via feeding. Results also suggest that temperature is the strongest climate change driver due to its influence on the metabolism of poikilothermic organisms (e.g. zooplankton and bivalves), which ultimately causes a concomitant increase of top‐down pressure on phytoplankton. Given the different thermal tolerance of cultured species, temperature is also critical to sort winners from losers, benefiting Crassostrea virginica over Mytilus edulis under the specific conditions tested in this numerical exercise. In general, it is predicted that bays with large rivers and high exchange with the open ocean will be more resilient under climate change when bivalve aquaculture is present.     

A Box Model for Ecosystem-Level Management of Mussel Culture Carrying Capacity in a Coastal Bay

The carrying capacity of shellfish aquaculture is determined by the interaction of cultured species with the ecosystem, particularly food availability to suspension feeders. A multiple box dynamic ecosystem model was constructed to examine the carrying capacity for mussel (Mytilus edulis) aquaculture in Tracadie Bay, Prince of Edward Island, Canada. Criteria for carrying capacity were based on chlorophyll concentration. The model was run in two different years (1998 and 1999) in which time series for three points inside the bay and a point outside the bay were available. This data set allows spatial validation of the ecosystem model and assessment of its sensitivity to changes in boundary conditions. The model validation process indicated that the differential equations and parameters used in the simulation provided robust prediction of the ecological dynamics within the bay. Results verified that mussel biomass exerts top-down control of phytoplankton populations. The model indicates that conditions observed during 1999 are more sensitive to grazing pressure from aquaculture than was observed during 1998, highlighting the importance of inter-annual variability in carrying capacity of the bay. This result is important from a management perspective because it emphasizes application of a precautionary policy and prediction in regulation of aquaculture activity in the bay. Retrospective scenarios showed that although the bay could yield greater mussel biomass production, stress on the environment would lead the ecosystem outside of its natural range of variation. Despite the spatial simplicity employed in the present model, it provides substantial management capability as well as an ecosystem-oriented approach to shellfish aquaculture.     

广州海域环境质量评价

根据2003年8月至2004年8月的水质调查数据,运用水质质量单项标准指数法、综合指数WQI法和富营养化评价法,对广州海域环境质量进行评价.结果表明,广州海域主要污染物质为DIN、PO₄^3--P、油类、Cu和Pb,其年平均浓度分别为1.87 mg·L^-1、0.049 mg·L^-1、0.107 mg·L^-1、6.07 μg·L^-1和1.43 μg·L^-1.其中,DIN的污染情况最严重,所有监测站位DIN含量均超过四类海水水质标准,其平面分布呈现从湾内向湾外递减的特征.受珠江径流和陆源排污等的影响,广州海域大部分处于重度污染,且严重富营养化,其单项污染指数、综合污染指数和富营养化指数的平均值分别为2.22、6.80和48.44,表现为从湾内向湾外递减的趋势,高值区均出现在黄埔港至狮子洋海域.     

基于GIS的虾夷扇贝养殖适宜性综合评价——以北黄海大小长山岛为例

由于水产养殖缺乏科学空间规划,近年来中国最大的虾夷扇贝(Patinopecten yessoensis)养殖基地长山群岛发生了扇贝大规模死亡现象。当地渔业主管部门急需水产养殖空间格局优化的技术手段和科学依据。采用叶绿素a浓度、海水表面温度、水深、透明度以及评价单元到渔港、城镇、旅游区和自然保护区的距离等指标,构建了虾夷扇贝养殖适宜性评价模型,并以大小长山岛海域为示范区,对该海域的虾夷扇贝的养殖适宜性进行了空间分析。结果表明:大小长山岛海域虾夷扇贝养殖适宜性较高且具有较大的空间变异,在不考虑海域使用冲突情形下,养殖适宜性指数在6.0—7.0以及7.0以上的海域占示范区的面积比例分别为26.04%(167.75 km2)和4.73%(44.06 km2),且高适宜性(SSI7.0)区主要分布在大长山岛西北和西南海域;而由于航道和水产养殖存在海域使用冲突,高适宜区面积大幅下降为19.56 km2。在此基础上对大小长山岛海域虾夷扇贝养殖空间格局优化提出了建议。利用一些简单的距离指标反映了陆地基础设施因素对水产养殖选址的影响,体现了海陆统筹的理念并可为海陆统筹技术方法研究提供重要借鉴。     

基于遥感分析的锦州湾海域填海造地变化

利用Landsat TM和高精度ALOS影像数据,在比较不同水体指数提取海域面积精度的基础上,利用改进的归一化差异水体指数(MNDWI),研究了1988、1995和2006年锦州湾海域填海造地情况.结果表明:1988-2006年间,锦州湾海域填海造地面积达23.63 km2,其中,12.38 km2被用作开发区建设,5.48 km2用于工业用地,3.47 km2用于码头建设,1.37 km2被用作养殖用地,0.93 km2被用为滨海浴场.大面积填海造地反映了锦州湾沿海城市建设和经济发展对土地的强烈需求,同时也必然会对该区域的生态环境造成较大影响,需要进一步加强监测和评价.     

我国主要海域海水养殖碳汇能力评估及其影响效应——基于我国9个沿海省份面板数据

随着海水养殖业的碳汇功能逐渐被认识和肯定,海水养殖不再单是一项经济活动,而是对环境具有正向影响的碳汇生态活动。以我国沿海9个省份为例,选取海水养殖业碳汇主要贡献的贝类和藻类海产品,并按照各自的碳汇方式对我国沿海地区2008—2015年海水养殖碳汇能力测算,进一步将9个沿海省份按照主要海域划分为渤海、黄海、东海、南海,利用LMDI模型从海水养殖的结构效应和规模效应角度分析碳汇能力的区域差异和主要影响因素。研究结果显示,黄海沿岸海水养殖碳汇能力最强,南海沿岸海水养殖的碳汇转化比例最高,规模效应与我国沿海地区海水养殖碳汇能力始终呈正相关,结构效应的作用显著但不稳定。基于上述结论,我国沿海地区碳汇养殖业应首先提升碳汇养殖技术、稳定海水养殖产量,其次注重优化养殖结构,对碳汇潜力巨大的贝类多加关注。     

Impact of Aquaculture on Commercial Fisheries: Fishermen’s Local Ecological Knowledge

The Bay of Fundy along the southwest coast of New Brunswick, Canada is one of the most densely stocked finfish aquaculture areas in the world. An inshore multi-species fishery that dates back to the earliest European settlement shares these waters, and has been the economic mainstay of coastal communities. These inshore fishermen are increasingly displaced by the expanding aquaculture industry. A recent study conducted among fishermen in Southwest New Brunswick recorded their observations about the environmental impact of finfish aquaculture and the consequences for their commercial fishery. Fishermen all reported significant environmental degradation around aquaculture sites. Within 2 years of an operation being established, fishermen reported that gravid female lobsters as well as herring avoid the area, scallop and sea urchin shells become brittle, scallop meat and sea urchin roe becomes discolored. The use of chemicals to control sea lice on farmed salmon has also caused lobster, crab and shrimp kills. These and other concerns suggest that more comprehensive and detailed studies are required to establish the environmental and economic interactions of aquaculture and the inshore fishery, as well as on the stocks on which that fishery rely. The study also points to the need for more effective use of fishermen’s knowledge in designing such studies.     

Adaptive genetic variation distinguishes Chilean blue mussels (Mytilus chilensis) from different marine environments

Chilean mussel populations have been thought to be panmictic with limited genetic structure. Genotyping‐by‐sequencing approaches have enabled investigation of genomewide variation that may better distinguish populations that have evolved in different environments. We investigated neutral and adaptive genetic variation in Mytilus from six locations in southern Chile with 1240 SNPs obtained with RAD‐seq. Differentiation among locations with 891 neutral SNPs was low (F_ST = 0.005). Higher differentiation was obtained with a panel of 58 putative outlier SNPs (F_ST = 0.114) indicating the potential for local adaptation. This panel identified clusters of genetically related individuals and demonstrated that much of the differentiation (~92%) could be attributed to the three major regions and environments: extreme conditions in Patagonia, inner bay influenced by aquaculture (Reloncaví), and outer bay (Chiloé Island). Patagonia samples were most distinct, but additional analysis carried out excluding this collection also revealed adaptive divergence between inner and outer bay samples. The four locations within Reloncaví area were most similar with all panels of markers, likely due to similar environments, high gene flow by aquaculture practices, and low geographical distance. Our results and the SNP markers developed will be a powerful tool supporting management and programs of this harvested species.     

外伶仃岛特大死鱼事件的水动力成因分析

外伶仃岛特大死鱼事件的水动力成因分析蔡瑜萱（广东省环境保护监测中心站）１９９２年１０月１６～１８日,珠海市伶仃岛石冲湾发生了网箱养殖鱼类大批死亡的严重事件。珠海市担杆镇人民政府向国家环保部门递交了“关于要调查外伶仃岛石冲湾养殖区海水严重受污的申诉书...