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11.
Gisela M. Figueiredo Hermógenes F. Leitão-Filho Alpina Begossi 《Human ecology: an interdisciplinary journal》1993,21(4):419-430
Local plants are a very important resource for the community of Gamboa, located at Itacuruçá Island, Sepetiba Bay, State of Rio de Janeiro, Brazil Ninety species of plants, belonging to 40 families, are used for a variety of purposes, such as food, construction, handicraft, and medicine. In a survey medicinal uses for plants were the most quoted by the community. Uses of medicinal plants within Gamboa and with other coastal communities are analyzed using diversity indices. Use by different categories of people based on sex, age, and economic activity was compared and significant differences were found among the groups compared, except for economic categories (fishermen and non-fishermen). The theory of island biogeography is shown to be useful for analyzing different levels of resource uses on different islands. 相似文献
12.
Test fishing with multimesh gillnets was performed in 103 acidified Swedish lakes before and 2–4 years after liming. In a subset of 39 lakes additional test fishing was carried out 5–9 years after liming. Taking into account the sampling biases due to differences between water temperature and number of nets used on different sampling occasions, an increase of the total CPUE, the number of species caught and recruitment of dominating species was evident after liming. Decreased recruitment was found for perch (Perca fluviatilis) at a pH below 5.2 and for roach (Rutilus rutilus) at a pH below 6.1. During the acidification phase and 2–4 years after liming acid-tolerant perch dominated the lakes, but when a longer time had elapsed after liming species dominance shifted and acid-sensitive planktivorous species increased in CPUE while perch decreased. 相似文献
13.
The variety of life-history patterns exhibited by the five species of wrasse common in Northern Europe are reviewed. The two larger wrasse species, the ballan, Labrus bergylta Ascanius, and cuckoo, Labrus mixtus (L.), are exploited through sport angling. The three smaller species, the corkwing, Symphodus (Crenilabrus) melops (L.), rock cook, Centrolabrus exoletus (L.) and goldsinny, Ctenolabrus rupestris (L.), are being exploited by a new fishery for use as parasite cleaners of farmed salmon.
The nature of salmon farming limits the wrasse fishery to a minimum size, restricted areas and the warmer months of the year. The fishery may be expected to alter population structure through selective removal of larger fish. Removal of dominant territorial males may affect social structures and removal of nest-guarding males would reduce egg survival. Quantitative models incorporating stock size and fishery requirements are now required. 相似文献
The nature of salmon farming limits the wrasse fishery to a minimum size, restricted areas and the warmer months of the year. The fishery may be expected to alter population structure through selective removal of larger fish. Removal of dominant territorial males may affect social structures and removal of nest-guarding males would reduce egg survival. Quantitative models incorporating stock size and fishery requirements are now required. 相似文献
14.
Patrick V. Kirch 《Human ecology: an interdisciplinary journal》1982,10(4):455-476
Archaeological evidence for prehistoric strategies of marine exploitation in Oceania may be profitably analyzed from an ecological perspective, in which individual sites and assemblages are viewed in the context of adaptation to local environmental constraints. This perspective is illustrated through the contrastive analysis of environment, technology, and faunal remains at three prehistoric Hawaiian sites. Differing strategies of marine exploitation evidenced for each site are shown to reflect local marine environmental conditions. An ecological approach shows greater promise for an understanding of prehistoric adaptation to marine environment than the typological analyses current in much archaeological work on fishing. 相似文献
15.
再议中国近海小黄鱼种群的划分问题 总被引:5,自引:1,他引:5
以往认为,中国近海小黄鱼可划分为3个种群.本研究从地理隔离、数量动态、形态解剖,分子遗传学和海洋水文等不同方面,重新审视了我国近海小黄鱼(Larimichthys polyactis Bleeker)种群的划分问题.研究表明:中国近海小黄鱼仅仅存在两个种群,即黄海南部和东海小黄鱼种群及渤海和黄海北部小黄鱼种群.主要证据有三:其一,分析1965年至今小黄鱼不同种群形态解剖学和分子遗传学重要文献,发现这些文献的结果仅仅支持黄海南部和东海小黄鱼是一个种群的结论;其二,依据1971-1982年我国10多个主要渔业公司小黄鱼捕捞统计资料,黄海南部和东海的小黄鱼在地理分布上几乎不存在隔离的现象.在冬季外海,黄海南部和东海小黄鱼栖息于同一个越冬场.进入春季后,它们从该越冬场分别向舟山渔场、鱼山渔场和吕泗渔场产卵洄游.同时,东海南部近海越冬场的小黄鱼向北作产卵洄游,在舟山渔场汇入外海来的小黄鱼鱼群中.从5-8月,黄海南部至东海仅存在一个小黄鱼索饵群体.而黄海北部和渤海小黄鱼群体与上述群体存在明显的地理隔离;其三,黄海南部和东海,近年来小黄鱼产量增长趋势一致,而同期的渤海和黄海北部小黄鱼资源量恢复不大. 相似文献
16.
基于表面等离子共振技术的配体垂钓技术能在蛋白质组水平上研究蛋白质的相互作用与功能,提供控制细胞功能的新靶标.其通过将受体固定在芯片表面,当被检测样品流过芯片表面时,配体与受体相结合, 实现俘获未知的相互作用的伙伴蛋白或复合体,并结合质谱技术鉴定出未知蛋白及其序列. 相似文献
17.
根据鄂霍茨克公海区狭鳕资源声学评估调查资料,研究了狭鳕分布状况及渔场环境特征,并分析了狭鳕行动分布与环境的关系.结果表明,8月公海区狭鳕密集群位于55°N以北、水深小于500m的海域,其主要分布水层在150~300m之间;调查期间狭鳕只为索饵群体,主要摄食太平洋磷虾,狭鳕密集区一般也为太平洋磷虾高密度分布区;8月公海区水温跃层大致在0~50m之间,强度为0.25℃ 相似文献
18.
Neville S. Barrett Graham J. Edgar Colin D. Buxton Malcolm Haddon 《Journal of experimental marine biology and ecology》2007,345(2):141-157
Most studies examining effects of marine protected areas (MPAs) on fish assemblages are potentially confounded, either because they are once off comparisons between fished and unfished locations, or because they are snapshot studies over a fixed period. Here we compare long-term changes within fully protected Tasmanian marine reserves with changes at external reference sites on an annual basis over the first ten years of protection. The results highlight the importance of long-term datasets for differentiating changes occurring over differing time scales. Notable results include a statistically significant increase in abundance of Latridopsis forsteri and large fish (> 300 mm) when examined across all reserves relative to controls, and a 10-fold increase in the abundance of large fish and a doubling of per site species richness of large fish within the Tinderbox Marine Reserve relative to controls. Short-term resident species that recruit sporadically show very different patterns in reserves compared to those that recruit regularly and have long-term age-class storage. While several recent reviews have suggested size of MPAs and duration of protection has little influence on the extent of recovery, our results suggest this is not the case and that responses can be slow, complex and species-specific. The extent of localised fishing pressure appeared to have a substantial influence on the degree of change detected, potentially confounding meta-analyses of recovery rates in MPAs if overlooked as a relevant parameter. 相似文献
19.
气候环境因子和捕捞压力对南海北部带鱼渔获量变动的影响 总被引:3,自引:0,他引:3
带鱼(Trichiurus japonicas)是南海北部的重要经济鱼类,其渔获量的变化不仅与捕捞压力有关,还与气候环境变化有关.为了研究气候变化和捕捞对南海北部带鱼渔获量变动的影响,使用长时间序列渔业统计资料和气候变化数据对1956-2006年的南海北部带鱼渔获量变动进行了分析.南海北部的带鱼渔获量变化可划分成因捕捞效应所产生的趋势变化和因气候环境变化所导致的渔获量变动.捕捞效应所产生的趋势变化可用Fox模型拟合,Fox模型拟合结果显示南海北部带鱼渔获量与捕捞努力量关系显著(P<0.01),说明捕捞压力的增长显著影响到南海北部带鱼渔获量的变化.移除捕捞效应所产生的趋势变化后,渔获量变动与中国南方降雨、南海北部海表水温、南海北部夏季季风以及南海北部冬季季风等气候因子呈显著正偏相关(P<0.04),与热带气旋影响指数呈显著负偏相关(P<0.03),这种相关说明南海北部带鱼渔获量变动还受气候环境因子的影响.南海北部带鱼渔获量可用捕捞努力量和气候变量来拟合,且拟合效果显著(R2=0.958,P<0.01),表明南海北部带鱼渔获量的变动归因于捕捞压力的单调增长和气候环境的变化.在南海北部的捕捞压力维持在现有水平下,未来的气候变化和人类活动引起营养盐的增加都可能有利于南海北部带鱼渔业产量的增加,且由于未来极端天气事件的频繁发生,可能还会引起带鱼渔获量的变动幅度加剧. 相似文献
20.
Laurne Mrillet Dorothe Kopp Marianne Robert Maud Mouchet Sandrine Pavoine 《Global Change Biology》2020,26(4):2106-2119
Global climate change has already caused bottom temperatures of coastal marine ecosystems to increase worldwide. These ecosystems face many pressures, of which fishing is one of the most important. While consequences of global warming on commercial species are studied extensively, the importance of the increase in bottom temperature and of variation in fishing effort is more rarely considered together in these exploited ecosystems. Using a 17 year time series from an international bottom trawl survey, we investigated covariations of an entire demersal ecosystem (101 taxa) with the environment in the Celtic Sea. Our results showed that over the past two decades, biotic communities in the Celtic Sea were likely controlled more by environmental variables than fisheries, probably due to its long history of exploitation. At the scale of the entire zone, relations between taxa and the environment remained stable over the years, but at a local scale, in the center of the Celtic Sea, dynamics were probably driven by interannual variation in temperature. Fishing was an important factor structuring species assemblages at the beginning of the time series (2000) but decreased in importance after 2009. This was most likely caused by a change in spatial distribution of fishing effort, following a change in targeted taxa from nephrops to deeper water anglerfish that did not covary with fishing effort. Increasing bottom temperatures could induce additional changes in the coming years, notably in the cold‐water commercial species cod, hake, nephrops, and American plaice. We showed that analyzing covariation is an effective way to screen a large number of taxa and highlight those that may be most susceptible to future simultaneous increases in temperature and changes in exploitation pattern by fisheries. This information can be particularly relevant for ecosystem assessments. 相似文献