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We investigated the spatio-temporal and environmental factors that affect the distribution and abundance of wintering anchovy and quantifi es the infl uences of these factors. Generalized additive models(GAMs) were developed to examine the variation in species distribution and abundance with a set of spatiotemporal and oceanographic factors, using data collected by bottom trawl surveys and remote sensing in the central and southern Yellow Sea during 2000–2011. The fi nal model accounted for 28.21% and 41.03% of the variance in anchovy distribution and abundance, respectively. The results of a two-step GAM showed that hour, longitude, latitude, temperature gradient(TGR), and chlorophyll a(Chl- a) concentration best explained the anchovy distribution(presence/absence) and that a model including year, longitude, latitude, depth, sea surface temperature(SST), and TGR best described anchovy abundance(given presence). Longitude and latitude were the most important factors affecting both distribution and abundance, but the area of high abundance tended to be east and south of the area where anchovy were most likely to be present. Hour had a signifi cant effect on distribution, but year was more important for anchovy abundance, indicating that the anchovy catch ratio varied across the day but abundance had an apparent interannual variation. With respect to environmental factors, TGR and Chl- a concentration had effects on distribution, while depth, SST, and TGR affected abundance. Changes in SST between two successive years or between any year and the 2000–2011 mean were not associated with changes in anchovy distribution or abundance. This fi nding indicated that short- and long-term water temperature changes during 2000–2011 were not of suffi cient magnitude to give rise to variation in wintering anchovy distribution or abundance in the study area. The results of this study have important implications for fi sheries management. 相似文献
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《水文地质工程地质技术方法动态》2009,(1)
地学数据保管方案
地学数据保管包括几个步骤：（1）制定规程以评估哪些地质实物资料和数据应加以保存、获取、吸收或注销;（2）建立一个系统来编排实物样品、数据和元数据;（3）为这些资料提供适当的保管设施;（4）使用户知晓这些地学数据和标本并提供使用途径;（5）确保样品和数据始终有用和可靠。 相似文献
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太阳辐射观测仪器的维护是观测员日常工作中经常遇到的情况,对仪器的良好维护能够保证辐射观测仪器的寿命及资料的准确性,提高观测资料质量,保证资料能够正常使用并发挥较高效益。 相似文献
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