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Growth of the red gurnard, Chelidonichthys kumu (Lesson and Garnot), from Pegasus Bay, Canterbury, was measured during 1966–67. Otoliths were used as an indicator of fish growth; mean length‐at‐age data were obtained from back‐calculated fish lengths at the time of formation of successive annual rings in the otoliths. Growth in length was found to be adequately expressed by the von Bertalanffy growth equation :

lt = 52.0 [1 ‐ e0.406 (t‐o.291)]

(where lt is the fork length in cm at age t). The length: weight relationship was:

w = 78.56 × 10‐4 l 3.072

(where w is the weight in grams). From this relationship, growth in weight was described by the equation:

wt = 1469 [1 ‐ e‐0.406 (t‐0.291)]3.  相似文献   
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The food and feeding habits of hoki (Macruronus novaezelandiae), southern blue whiting (Micromesistius australis), javelin fish (Lepi‐dorhynchus denticulatus), ling (Genypterus blacodes), smooth rattail (Coelorinchus aspercephalus), silverside (Argentina elongata), and small‐scaled notothenid (Notothenia microlepidota) sampled from the Campbell Plateau in 1979 were examined. The importance of prey items in the diet has been assessed by an ‘index of relative importance’, which combines measurements of frequency of occurrence, number, and weight of prey. Hoki, southern blue whiting, and javelin fish are pelagic feeders. Hoki preyed largely on natant decapod crustaceans, amphipods, and myctophid and photichthyid fishes. The main prey of southern blue whiting were amphipods, natant decapods, and euphausiids. Javelin fish fed on natant decapods, amphipods, and small squid. Seasonal and regional differences in feeding, and dietary changes with length of fish were evident. Ling, smooth rattail, silverside, and small‐scaled notothenid are predominantly benthic feeders. Ling preyed on natant decapods, macrourid fishes, and small hoki. The diet of rattail comprised natant decapod crustaceans, opal fishes (Hemerocoetes spp.), and poly‐chaetes. Silverside fed almost solely on salps. Salps, amphipods, brachyuran crustaceans, and opal fishes were the main prey of small‐scaled notothenid.  相似文献   
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珠江口水域鳓鱼生长和死亡参数估算   总被引:7,自引:0,他引:7  
根据1996—1998年期间在珠江口及邻近海域采集的鳓鱼(Ilisha elongata Bennett)生物学资料,应用FiSATⅡ软件进行鳓鱼的生长和死亡参数估算。用ELEFANI技术拟合的von Bertalanffy生长方程参数分别为L∞=53.13cm(叉长)、κ=0.37a^-1及t∞=-0.62a,用Pauly经验公式计算的自然死亡系数为M=0.74,以长度变换渔获曲线法估算的总死亡系数为Z=2.53。运用Beverton-Holt模型分析该群体的最适捕捞死亡系数为F=2.5,最适开捕年龄和叉长分别为1.6龄和29.8cm,目前该群体已处于捕捞过度状态,尤其以捕捞幼鱼的问题较为突出。建议南海北部鳓鱼的最小可捕规格应为叉长30cm。  相似文献   
5.
香蒲、灯心草人工湿地的研究─Ⅱ.净化污水的空间   总被引:26,自引:0,他引:26  
应用测定流水中溶氧量的方法,测定了长薄鳅的耗氧率,耗氧量及窒息点.试验表明:长薄鳅的耗氧率(Y’)随鱼体重(W,g)的增加而增大,其关系式分别为:Y’=186.576W(-0.2043),Y=0.186W(0.7962).温度对长薄鳅的耗氧率有影响,在13-30C范围内,耗氧率随水温升高而逐渐增大.耗氧率的温度敏感区域是13-23C和28-30C,而在23-28C范围内变化幅度较小,标准代谢量变化  相似文献   
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Tamarix elongata Ledeb is a desert shrub found in the desert region of Northwest China and is commonly cultivated as a sand‐holding plant in this region. To understand its water requirement and the effects of climate conditions on its growth, trunk xylem sap flows of irrigated 8‐year‐old Tamarix elongata Ledeb plants were monitored continuously with heat‐pulse sap flow meters for the entire season. Soil moisture contents at 0–300 cm layer depth were also measured with a tube type time domain reflectometry (Tube‐TDR). Meteorological factors, i.e. solar radiation, air temperature, relative humidity and wind speed were simultaneously monitored by an automatic weather station at the site. Daily and seasonal variations of the trunk sap fluxes and their correlations with the meteorological factors, reference evapotranspiration and soil moisture contents in the root‐zone were analysed. The results indicated that frost influenced the trunk sap flux greatly under irrigated conditions, although the flux generally fluctuated with the variation of environmental factors and showed a mean trunk sap flux of 4·18 l d?1. There was a significantly exponential relationship between sap flux and the reference value of crop evapotranspiration, with a correlation coefficient of R2 = 0·7172. The sap flux also had a significant correlation with the soil water contents at a depth of 150–300 cm from soil surface (R2 = 0·5014). The order of the main meteorological factors affecting the sap flux of Tamarix elongata Ledeb trees was solar radiation > air temperature > vapour pressure deficit > relative humidity > wind speed. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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