Monitoring fish movement patterns in a reservoir using horizontally scanning split-beam techniques     

Steig  Tracey W.; Johnston  Samuel V. 《ICES Journal of Marine Science》1996,53(2):435-441

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Species composition and biomasses of fishes in tropical seagrasses at Groote Eylandt, northern Australia     

S.J.M. Blaber  D.T. Brewer  J.P. Salini  J.D. Kerr  C. Conacher 《Estuarine, Coastal and Shelf Science》1992,35(6)

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Upstream dams and downstream clams: growth rates of bivalve mollusks unveil impact of river management on estuarine ecosystems (Colorado River Delta, Mexico)     

B. R. Schne  K. W. Flessa  D. L. Dettman  D. H. Goodwin 《Estuarine, Coastal and Shelf Science》2003,58(4):715-726

We studied how the extensive diversion of Colorado River water, induced by dams and agricultural activities of the last 70 years, affected the growth rates of two abundant bivalve mollusk species (Chione cortezi and Chione fluctifraga) in the northern Gulf of California. Shells alive on the delta today (‘Post-dam’ shells) grow 5.8–27.9% faster than shells alive prior to the construction of dams (‘Pre-dam’ shells). This increase in annual shell production is linked to the currently sharply reduced freshwater influx to the Colorado River estuary. Before the upstream river management, lower salinity retarded growth rates in these bivalves. Intra-annual growth rates were 50% lower during spring and early summer, when river flow was at its maximum. Growth rates in Chione today are largely controlled by temperature and nutrients; prior to the construction of dams and the diversion of the Colorado River flow, seasonal changes in salinity played an important role in regulating calcification rates.Our study employs sclerochronological (growth increment analysis) and geochemical techniques to assess the impact of reduced freshwater influx on bivalve growth rates in the Colorado River estuary. A combination of both techniques provides an excellent tool to evaluate the impact of river management in areas where no pre-impact studies were made.  相似文献   

海水仔稚鱼脂类营养研究进展   总被引：3，自引：1，他引：3  

刘镜恪  周利  雷霁霖 《海洋与湖沼》2002,33(4):446-452

近年来国外海水仔稚鱼脂类营养研究取得了重要进展。作者从海鱼鱼卵和早期仔稚鱼阶段的脂肪酸成分、海水仔稚鱼饥饿时脂肪酸的保存、海水仔稚鱼脂类的消化、吸收和运输、饲料中磷脂的作用和影响、饲料磷脂与甘油三酯的效率、饲料的必需脂肪酸、必需脂肪酸的定量需要、高度不饱和脂肪酸以及EPA和DHA比例的重要性等方面综述脂类营养对海水仔稚鱼生长的影响  相似文献   

Seasonality and interannual variability of freshwater inflow to a large oligohaline estuary in the Northern Gulf of Mexico     

Y. Jun Xu  Kangsheng Wu 《Estuarine, Coastal and Shelf Science》2006,68(3-4):619

Quantity, timing, duration, and fluctuation of freshwater inflow are important factors affecting the development and health of aquatic and adjacent wetland ecosystems in coastal estuaries. This study assessed six decades of freshwater inflow from the Amite River, Tickfaw River, and Tangipahoa River watersheds to Lake Pontchartrain, a large oligohaline estuary in the Northern Gulf of Mexico, whose flood waters caused recent damage to the city of New Orleans in the aftermath of Hurricane Katrina. By utilizing the long-term (1940–2002) river discharge and climatic data from the three major tributary watersheds, monthly and annual freshwater inflows have been quantified and their spatial and temporal variations have been analyzed. On average, the three rivers discharged (±standard error) 0.27 ± 0.04 km³ freshwater monthly and 3.29 ± 0.15 km³ freshwater annually into the lake estuarine system, with the highest inflow from the Amite River (0.16 ± 0.03 m³ mon⁻¹, and 1.91 ± 0.09 km³ yr⁻¹) and the lowest inflow from the Tickfaw River (0.03 ± 0.00 km³ mon⁻¹, and 0.34 ± 0.02 km³ yr⁻¹). A distinct seasonality was evident with over 69% of the total annual inflow occurring during December and May (wet months) and with a low flow period from August to November (dry months). The monthly inflow during the wet months was positively correlated with the monthly precipitation (r² = 0.64), while the monthly inflow during the dry months was subject to evapotranspiration. Furthermore, the study found a 20-year low flow period from 1954–1973 (2.76 ± 0.24 km³ yr⁻¹) and a 24-year high flow period from 1975–1998 (3.84 ± 0.24 km³ yr⁻¹), coinciding with both the climate variation and population growth in the watersheds.  相似文献   

Multi-scale spatial variability in fish assemblages associated with Posidonia oceanica meadows in the Western Mediterranean Sea     

Joan Moranta  Miquel Palmer  Gabriel Morey  Ana Ruiz  Beatriz Morales-Nin 《Estuarine, Coastal and Shelf Science》2006,68(3-4):579

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秋季黄海中南部鱼类群落对饵料生物的摄食量   总被引：8，自引：0，他引：8  

薛莹  金显仕  赵宪勇  梁振林  李显森 《中国海洋大学学报(自然科学版)》2007,37(1):75-82

研究鱼类与饵料生物之间食物定量关系进而为多鱼种资源评估提供依据,2000~2002年秋季(10~11月)在黄海中南部海域进行了定点底拖网调查,应用Eggers模型,计算了带鱼(Trichiurus lepturus)、小黄鱼(Pseudosciaena polyactis)、黄(Lophius litulon)、细纹狮子鱼(Liparis tanakae)等23种鱼类在秋季对饵料生物的摄食量。结果表明:黄海中南部23种鱼类在秋季对饵料生物的总摄食量约为309万t,其中,鱼(Engraulis japonicus)的摄食量最高(在250万t以上),占总摄食量的80.9%。中上层和底层鱼类对饵料生物的摄食量分别为262万t和47万t左右,占总摄食量的84.7%和15.3%,鱼和细纹狮子鱼分别是中上层和底层鱼类中最主要的捕食者。磷虾类是中上层鱼类最主要的食物来源,其次是桡足类、端足类和毛颚类;虾类和鱼类是底层鱼类最主要的食物来源,其次是磷虾类。太平洋磷虾(Euphausia pacifica)、中华哲水蚤(Calanus sinicus)、细长脚虫戎(Themisto gracilipes)、脊腹褐虾(Crangon affinis)和鱼同时是黄海中南部被摄食量最高的5种饵料生物,它们被摄食的生物量之和约为233万t,占总摄食量的75.5%。  相似文献   

A meta-analysis of the status of ICES fish stocks during the past half century   总被引：2，自引：0，他引：2  

Sparholt  Henrik; Bertelsen  Mette; Lassen  Hans 《ICES Journal of Marine Science》2007,64(4):707-713

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A requiem for the use of 20 log10 Length for acoustic target strength with special reference to deep-sea fishes     

McClatchie  S; Macaulay  G.J; Coombs  R.F 《ICES Journal of Marine Science》2003,60(2):419-428

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Salmon lice, Lepeophtheirus salmonis (Kroyer), infestation in sympatric populations of Arctic char, Salvelinus alpinus (L.), and sea trout, Salmo trutta (L.), in areas near and distant from salmon farms     

Bjorn  Pal Arne; Finstad  Bengt 《ICES Journal of Marine Science》2002,59(1):131-139

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