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61.
62.
A marked decline in the contribution by Marovo Lagoon to the annual total bêche-de-mer production of the Solomon Islands from
58% in 1989 to 17% in 2003 prompted investigation of their current biomass and diversity. We also assessed changes to critical
ecological services and the prospects for population recovery following a fisheries closure. Day time and nocturnal transects
revealed a mean abundance of 32.4 (SD = 5.3) low value species per ha (e.g. Holothuria atra, H. edulis, H. coluber and Thelenota anax) and 15.2 (SD = 2.7) high value species per ha (e.g. H. fuscogilva, Actinopyga lecanora, Stichopus hermanni and Thelenota ananas). Following a 17 month closure of the fishery (2005–2007), the abundance of bêche-de-mer was reported by local fisherman
to have increased; however, no scientific studies were conducted that can substantiate this community held belief. The current
study aimed to document the impact of re-opening the fishery in 2007 and documented a decline in high value species of 9%
over a 5 month period following the opening of the fishery, while low value species continued to increase in abundance by
11%, over the same period based on nocturnal surveys. Continued observation of the recovery, post closure, and any subsequent
harvest in Marovo will be required to properly understand population dynamics and provide a sustainable harvest plan for bêche-de-mer
in the future. 相似文献
63.
A regional climate change impact assessment was conducted which investigated the timing of the first appearance of furunculosis
caused by the bacterium, Aeromonas
salmonicida, in fish of the Ouje-Bougoumou region of northern Quebec, Canada. Historical data were used to assess whether there was a
temporal relationship between increased temperatures (observed climate data) and the appearance of furunculosis (traditional
environmental knowledge was used to provide context). To project future impacts of climate change, climate models and lake
models were used. Regression analysis revealed a significant, positive temporal trend in mean air temperature. The temperature
range conducive to A. salmoncida survival coincided with the first appearance of furunculosis. In addition, it is predicted that lake temperatures will remain
suitable for the presence of A. salmonicida into the future; it is likely that the disease will persist throughout the twenty-first century. Climate change appears to
be a factor explaining the onset of furunculosis; however, other factors/stressors cannot be discounted, such as, the effects
past mining activities near the lakes of the Ouje-Bougoumou region have had on the body burden of contaminants in the fish
(and the potential effects on the fish immune system). 相似文献
64.
65.
Anne Christine Knag Marion Sebire Ian Mayer Sonnich Meier Patrick Renner Ioanna Katsiadaki 《Chemosphere》2013
Oil pollution from various sources, including exploration, production and transportation, is a growing global concern. The highest toxicity of hydrocarbon pollutants is associated with the water-soluble phase compounds, including naphthenic acids, a known component found in all hydrocarbon deposits. Recently, naphthenic acids (NAs) have shown estrogenic and anti-androgenic effects in vitro. For this reason we investigated the potential effects of two commercial mixtures of naphthenic acids on fish in vivo, using the three-spined stickleback (Gasterosteus aculeatus) as a model species. 相似文献
66.
Ian C. Gilby Lauren J. N. Brent Emily E. Wroblewski Rebecca S. Rudicell Beatrice H. Hahn Jane Goodall Anne E. Pusey 《Behavioral ecology and sociobiology》2013,67(3):373-381
Coalitionary aggression occurs when at least two individuals jointly direct aggression at one or more conspecific targets. Scientists have long argued that this common form of cooperation has positive fitness consequences. Nevertheless, despite evidence that social bond strength (which is thought to promote coalition formation) is correlated with fitness in primates, cetaceans, and ungulates, few studies have directly examined whether coalitionary aggression improves reproductive success. We tested the hypothesis that among free-ranging chimpanzees (Pan troglodytes schweinfurthii), participation in coalitionary aggression increases reproductive output. Using 14 years of genetic and behavioral data from Gombe National Park, Tanzania, we found that coalitionary aggression increased a male’s chances of (A) siring offspring, compared to other males of similar dominance rank, and (B) ascending in rank, a correlate of future reproductive output. Because male chimpanzees form coalitions with many others within a complex network, we used social network analysis to identify the types of connections correlated with these fitness benefits. The beneficiaries of coalitionary aggression were males with the highest “betweenness”—that is, those who tended to have coalition partners who themselves did not form coalitions with each other. This suggests that beyond simply recognizing third-party relationships, chimpanzees may use this knowledge to choose coalition partners. If so, this is a significant step forward in our knowledge of the adaptive value of social intelligence. Regardless of mechanism, however, this is the first evidence of genetic benefits of coalitionary aggression in this species, and therefore has important implications for understanding the evolution of cooperation. 相似文献
67.
Ed Gidman Royston Goodacre Bridget Emmett Lucy J. Sheppard Ian D. Leith Dylan Gwynn-Jones 《Water, Air, & Soil Pollution: Focus》2005,4(6):251-258
The potential for metabolic fingerprinting via Fourier-transform infrared (FT-IR) spectroscopy to provide a novel approach for the detection of plant biochemical responses to N deposition is examined. An example of spectral analysis using shoot samples taken from an open top chamber (OTC) experiment simulating wet ammonium deposition is given. Sample preparation involved oven drying and homogenisation via mill grinding. Slurries of a consistent dilution were then prepared prior to FT-IR analysis. Spectra from control, 8 and 16 kg N ha?1 yr?1 treatments were then subjected to cross-validated discriminant function analysis. Ordination diagrams showed clear separation between the three N treatments examined. The potential for using Calluna vulgaris (L.) Hull as a bioindicator of N deposition is further evident from these results. The results also clearly demonstrate the power of FT-IR in discriminating between subtle phenotypic alterations in overall plant biochemistry as affected by ammonium pollution. 相似文献
68.
69.
长江中游历来是长江流域水灾最严重的地区,研究历史时期这一地区水灾发生的变化波动并找出其与厄尔尼诺事件的遥相关,将有助于对长江中游水灾发生的预测。对这二个时间序列自1525年以来的数据进行了统计学分析。结果表明,水灾发生的主要周期比厄尔尼诺事件发生的周期要长:后者主要表现为2年和3~4年的振动,而前者的主要周期为2年、8年和40年,其显著性也没有后者明显(但都超过了0.03的置信度)。通过进一步分析历史时期长江中游水灾与厄尔尼诺事件的耦合振动,发现它们之间存在显著的遥相关。结果表明,长江中游水灾对厄尔尼诺现象的响应不仅存在着如许多中国学者相信的短期滞后(如:1年),而且还存在着比较长时间的滞后(最长可达8年)。研究结果同时表明,如果厄尔尼诺事件发生的相距时间愈短,这一时期长江中游水灾响应的滞后时间也愈短,反之亦然。 相似文献
70.
Ian J. Bateman 《Journal of Environmental Planning and Management》1996,39(1):21-44
The UK Forestry Commission's recently implemented Community Woodland scheme sets out to provide new recreational woodland facilities near to towns and cities where such resources are in short supply. This study examines household willingness to pay (WTP) for such a proposed woodland by means of the contingent valuation (CV) method. A stratified sample of 325 households in Wantage, Oxfordshire, was interviewed and asked to state both their annual and per-visit WTP. Analysis of a number of recognized potential biases suggested that the results obtained must be treated with caution although we argue that the CV provides a useful ballpark indication of preferences. A simultaneous CV survey of farmers' willingness to accept compensation for converting agricultural land into woodland proved to be far more robust, despite a small sample size. We conclude that farmers are more familiar with the concept of assessing potential compensation than are households with estimating hypothetical payments for increased provision of public goods. 相似文献