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生态浮床原位修复对海水养殖池塘底栖动物群落结构的影响 总被引：2，自引：0，他引：2
选取广东阳江面积为33.33 hm2的海水养殖池塘,混合粗养黄鳍鲷(Sparus latus)、鲻(Mugil cephalus)、凡纳滨对虾(Litopenaeus vannamei)和锯缘青蟹(Scylla serrata),养殖密度为鱼类750 kg/hm2、虾类2 250 kg/hm2、蟹7.5 kg/hm2,投喂罗氏沼虾配合饲料2号和3号,每天2次,每次约280 kg,每周投放1次光滑河蓝蛤(Potamocorbula laevis)250 kg作为蟹类活饵料。通过铺设近2 000个由塑料管和普通渔网构成的浮床单体栽种海马齿(Sesuvium portulacastrum),研究生态浮床原位修复技术对海水养殖池塘底栖动物群落结构的影响,探讨底栖动物群落结构变化特征与海水养殖池塘水质的关系。结果显示,试验区底栖动物的种类相比对照区的7种增加到10种,出现了一些耐污能力较差的甲壳类(中华蜾蠃蜚Corophium sinensis和齿掌细身钩虾Maera serratipalma)以及腹足类(珠带拟蟹守螺Cerithidea cingulata)。各次采样中试验区底栖动物个体丰度均高于对照区,平均由2 725个/m2增加到2 764个/m2。试验区的Shannon-Wiener多样性指数(H')和Margalef丰富度指数(D)较对照区均有显著提高(P0.05),分别由初始的0.68和0.67提高到0.81和0.85。试验区表现出比对照区更强的底栖动物多样性恢复能力,表明生态浮床原位修复技术能较好地改善海水养殖环境。 相似文献
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Feeding strategy of the non‐native rainbow trout,Oncorhynchus mykiss,in low‐order Patagonian streams
The dietary composition and feeding strategy of rainbow trout, Oncorhynchus mykiss (Walbaum), in two low‐order Patagonian streams were studied. Benthic macroinvertebrate availability was estimated in both riffles and pools. Fish stomach contents were examined to determine prey richness and diversity, prey electivity, food‐niche width, and the feeding strategy employed by trout throughout the year. Availability of benthos varied seasonally with Ephemeroptera, Trichoptera, Plecoptera and Diptera species dominating. Rainbow trout diet was composed mainly of benthic macroinvertebrates, followed by terrestrial insects, fish, algae and plants. Different trout size classes segregated the use of food resources to reduce predation pressure. Elected prey included organisms displaying no to high mobility. A high feeding plasticity allows trout to buffer changes in food availability by switching from a specialised to a generalised feeding behaviour. Consequently, trout may exploit abundant but temporary food resources opportunistically, which would explain their marked expansion in Patagonian environments. 相似文献
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Abstract— We used two densities of eggs (low=900 eggs/m2 ; high=5100 eggs/m2 ) in laboratory experiments to estimate the recovery efficiency of the Brown benthos sampler for collecting fish eggs from gravel substrate and to determine if differences (e. g., 5-fold) in egg density in the substratum could be detected with the sampler. The mean egg recovery efficiency of the sampler in the low and high density treatments was 30% (SE=8.7) and 35% (SE=3.8), respectively. The difference between the treatment means was not significant. Therefore, data from the two treatments were pooled and used to estimate the recovery efficiency of the sampler (32.7%, SE=4.4). However, we were able to detect a 5× difference in the number of eggs collected with the sampler between the two treatments. Our estimate of the recovery efficiency of the sampler for collecting fish eggs was less than those reported for the sampler's efficiency for collecting benthic macroinvertebrates. The low recovery efficiency of the sampler for collecting fish eggs does not lessen the utility of the device. Rather, ecologists planning to use the sampler must estimate the recovery efficiency of target fauna, especially if density estimates are to be calculated, because recovery efficiency probably is less than 100%. 相似文献
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Linlin Chen Konstantin A. Lutaenko Xiaojing Li Xinzheng Li Zhengquan Zhou Baoquan Li Olga N. Pavlyuk Tatyana S. Tarasova 《水产资源保护:海洋与淡水生态系统》2020,30(7):1451-1475
- A review of the long‐term changes and variations in benthic communities and the current status of the marine invasive species (MIS) in shallow waters of the Yellow Sea (Chinese sector) and the Sea of Japan (Russian and partly Korean sectors) is presented. This paper reflects on the progress and lessons learned, recommending actions for the future about the conservation of biodiversity.
- In the Bohai Sea, the benthic ecosystem has been degenerating due to anthropogenic activities such as overfishing and pollution since the 1950s. The dominant position of K‐strategy species is gradually being lost and replaced by R‐strategy species. In the Yellow Sea, the macrobenthic community is different from other areas due to the Yellow Sea Cold Water Mass. Many economic species have been destroyed, and the biotic structure has changed significantly due to overfishing and climate change.
- In the Russian sector of the Sea of Japan, the macrobenthic communities in the shallow‐water soft bottom have generally been in a stable condition for the last decades, except for some heavily polluted or disturbed areas due to dredging operations. The abundance of select large invertebrate species has changed considerably due to commercial fishing and poaching. Variations in macro? and meiobenthic communities under aquaculture conditions have occurred on a local scale during the last five decades.
- MIS show obvious differences between China and Russia in the following aspects: introduction pathways of MIS, composition and number of non‐native species, threats and impacts of MIS to native communities and ecosystems, and economic and public health impacts.
- Long‐term monitoring programmes should be developed to reveal future biotic changes and to separate the effects of cyclic variations of benthic communities from the impacts of pollution and eutrophication. Standardization of sampling procedures is required to compare changes/alternations in benthos across various regions worldwide.
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Robyn E. Jones Richard K.F. Unsworth Jon Hawes Ross A. Griffin 《水产资源保护:海洋与淡水生态系统》2021,31(6):1379-1391
- Biodiversity in turbid aquatic environments is commonly assessed using extractive sampling methods that damage the seabed. Underwater cameras equipped with clear liquid optical chambers (CLOCs) for the assessment of seabed habitats and species are a non-extractive alternative and have been applied in turbid environments globally. A CLOC is a body of clear liquid positioned in front of a camera to reduce the scattering of light that would otherwise occur when passing through the turbid water it displaces. Here, we test and quantify the effectiveness of a CLOC for marine benthic biodiversity assessments over gradients of increasing turbidity.
- The addition of a CLOC to a conventional benthic camera system significantly enhanced the quality of information gathered. Images acquired using the CLOC system consistently recorded statistically higher values of image quality (49% increase, based on the clarity of the image), seabed visible within the drop-down frame (34% increase), and European Nature Information System habitat level identification (49% increase). Furthermore, it was found that the ‘annotation success’ of taxa (classification of a specimen to family level or higher) was found to increase between individual experts in the presence of a CLOC. A reduced sampling effort was also identified when using a CLOC. Taxonomic richness increased by 27% when comparing the same number of image stills collected with and without the CLOC.
- By reducing the limitations of underwater visibility previously attributed to underwater cameras, this concept extends the potential for use of non-destructive survey techniques and allows for future users to collect robust information of an area, making better informed management decisions.
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Cataixa López María Bas-Silvestre Adriana Rodríguez Alberto Brito Sabrina Clemente 《水产资源保护:海洋与淡水生态系统》2021,31(4):748-763
- In the current context of climate change, benthic cnidarians of the genus Palythoa have been suggested to be resistant owing to their intrinsic biological characteristics. In tropical regions, some species are currently proliferating in areas where environmental conditions are less suitable for other organisms, even replacing hard coral ecosystems.
- Considering their tropical affinities, phase-shifts towards Palythoa-dominated areas could become more frequent in future climate change scenarios, leading to changes in ecosystem organization. The aim of this study was to evaluate the effect of climate change stressors in two common Palythoa spp. with different habitat affinities within a subtropical region, and the effect upon their predator–prey interactions.
- The results of this experimental study demonstrated that colonies of P. aff. clavata and P. caribaeorum were significantly affected by exposure to temperature and pH conditions predicted for 2100 in the Canary Islands, during 62 days.
- Despite zoantharians’ lack of carbonate in their body wall, Palythoa spp. were most affected in their growth rates by lowered pH, and colonies significantly decreased in weight and size. Although all colonies exhibited symptoms of bleaching at high temperature, a reduction in chlorophyll content was also observed at low pH.
- Predation by Platypodiella picta crabs decreased on P. aff. clavata exposed to acidic conditions, which may compensate for the lowered ecological performance of the species in these climate change conditions. In contrast, P. picta was able to actively feed on P. caribaeorum colonies regardless of the experimental conditions.
- Despite being suggested as winner species in a climate change scenario, our study demonstrated that low pH negatively impacted Palythoa spp. survival. If the species are not able to acclimatize to the new conditions, changes in their populations may be expected, although their magnitude could be ameliorated by means of a decrease in predation rates.
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Maria Paola Ferranti Javier Guallart Virginia Cortella Giacomo Terenziani Mariachiara Chiantore 《水产资源保护:海洋与淡水生态系统》2021,31(7):1912-1917
- Effectiveness of restoration/repopulation measures may be strongly hindered by the ability of the target species to cope with the environmental conditions of the receiving area.
- Although a species has been reported previously for a given area, the environmental conditions and human pressures may have changed, potentially making any restoration attempt ineffective. Evidence is provided showing that the endangered ferruginous limpet Patella ferruginea can complete its reproductive cycle in the northernmost sector of the western Mediterranean.
- This supports the idea that the reintroduction and the strict protection of P. ferruginea in the extreme north of its historical geographic range could be effective for the recovery of the species in this area and ultimately the establishment of reproductively viable and stable populations.
- Verification of gonadal maturation of specimens experimentally established on the Gulf of Genoa (Ligurian Sea) coastline, as well as evidence of sex change in one individual (the first outside the Alboran Sea), provides further support of the potential for individuals to complete their reproductive cycle in this area.
- The results support the potential of actions for the restoration of viable populations of the species along the Ligurian coasts through the introduction of juveniles obtained exclusively by aquaculture techniques, in order to mitigate any impact on donor sites.