摘要
对采自青岛近岸海域的马粪海胆从其对各种饵料的选择和摄食吸收、温度与自身湿重对其摄食率的影响以及摄食活动特征等方面进行实验生态学研究。结果表明 ,马粪海胆在多种海藻并存的情况下 ,对海带及裙带菜等褐藻具明显的选择性 ,对石花菜及孔石莼等藻类的喜好性较差 ,但在食物匮乏条件下 ,马粪海胆的食谱则变得相当广泛。马粪海胆对裙带菜及海带的摄食率均明显高于孔石莼 ,但其对孔石莼的饵料吸收率则高于海带及裙带菜。马粪海胆的摄食受温度条件及自身湿重的影响 ,温度偏离适宜范围对摄食有抑制作用 ,日摄食率与湿重呈显著的指数下降关系 ,摄食率与湿重、温度因子可建立具较高可靠性的指数回归模型。马粪海胆对食物的口面吸附与对其摄食密切相关 ,其摄食活动与湿重呈显著的指数下降关系 ,而与排便活动呈显著的正相关 ,随湿重增加排便活动虽呈下降趋势 ,但未达显著水平。自然光照条件下马粪海胆的夜间摄食强度通常高于日间 ,但在全遮盖的无光照条件下这种昼夜摄食差异则变得不显著 ;对摄食活动的连续观测表明马粪海胆的摄食活动受光强变化的影响 ,其摄食活动的高峰出现在光强减弱的早间及傍晚 。
The sea urchin,Hemicentrotus pulcherrimus,an economically important species in Northern Chinese littoral benthic systems, has been heavily exploited by local fisheries in recent decades. Despite this fact, basic knowledge of the urchin's feeding biology is still scarce. Experimental feeding ecology studies of H. pulcherrimus focused on food preference, food consumption and assimilation, feeding activity in this paper. The sea urchins used in the studies were sampled by diving from the shallow subtidal zone of Qingdao beach,north of China. The algae used in the experiments were also collected from the littoral zone. The algae assemblage includes: Laminana japanica, Undaria pinnatifida, Sargassum sp., Gelidium amansis,Ulva pertus and Grateloupia filicina. Results of a food preference experiment showed that H. pulcherrimus had an obvious preference for brown algae (Laminariales) such as Laminana japanica and Undaria pinnatifida over the other seaweeds. In addition, preference indexes for Und.and Lam. exceeded indices for other seaweeds; in part because their habitats were more similar to that of H. pulcherrimus than others. At low food levels H. pulcherrimus becomes omnivorous, feeding on any food encountered such as remnants of dead animals or plants. In starving conditions, H. pulcherrimus cannibalize one another. Measured consumption rates and assimilation efficiency of three algae Laminana japanica,Undaria pinnatifida and Ulva pertus indicate that the consumption rate of Ulv. was the lowest, but had the highest assimilation efficiency. This may be due in part to a longer residential time in sea urchin's intestines. Food consumption rate of H. pulcherrimus varied with the temperature conditions, falling off if the temperature deviated from a temperature optimum. The consumption rate at 14℃ was higher than that at 9℃ or 19℃. Food consumption rate also changed with the body weight of H. pulcherrimus.The Food consumption rate(F_c) had a significant negative correlation with body weight(W)(α<0.01), the regression equation was F_c=64.89W^(-1.1641). Based on the experimental results, a multiple regression model of food consumption rate relative to body weight and water temperature(T) was: F_c=63.10W^(-1.131)(0.995)~V, where V=(T-13.8)~2. Significance tests of multiple correlation coefficient and partial regression coefficient of the model show that they were significant(α<0.05). Feeding frequency(F_f) of H. pulcherrimus had a significant negative correlation with body weight(α<0.01); the regression equation was F_f=158.36W^(-0.8001). The sea urchin adsorbed fragments of sand and algae on its body surface to shade itself. The sea urchin almost adsorbed nothing but food chips on its ventral surface; and the rate of adsorption of fragments on its ventral surface had a close correlation with its feeding. The formula for the relationship between feeding frequency and food adsorption frequency of ventral surface(A_d) was F_f=5.0122 A^(0.3936)_d.We also found that defecation frequency(D_f) of (H. pulcherrimus) decreased with the increasing body weight. Feeding activity(A_c) (including food feeding and food adsorption)of H. pulcherrimus had a significant correlation with defecation frequency(α<0.05), The regression formula was as follows: D_f=5.4271 A^(0.6194)_c. In natural light conditions the food consumption of H. pulcherrimus in the daytime was higher than that of night, but in conditions of constant darkness, food consumption was unaffected by time of day. Feeding activity of H. pulcherrimus varied with the light intensity, high light intensity restrained the urchin's feeding activity in the daytime, while in suitable weak light intensity(5～30lx) condition at dawn and dusk, the sea urchin would have a higher feeding activity than those of other time periods.
出处
《生态学报》
CAS
CSCD
北大核心
2004年第5期1006-1014,共9页
Acta Ecologica Sinica
基金
国家自然科学基金资助项目 ( 3 0 0 70 5 93)~~
关键词
马粪海胆
海胆
摄食习性
摄食生态
实验生态
Hemicentrotus pulcherrimus
sea urchin
feeding features
feeding ecology
experimental ecology
