研究了天津厚蟹 Helice tientsinensis对盐度和温度的耐受性。天津厚蟹对盐度的耐受能力极强，在温度9～34℃盐度为0的淡水介质中均能存活96 h以上；在10℃、20℃及30℃的高渗介质中暴露96 h后，天津厚蟹全部存活的盐度分别是65、56和50，全部死亡的盐度分别为83、74和68。天津厚蟹对低温的耐受力较强，在0、30和50盐度水平下，耐受低温的能力差别较大，能耐受96 h的最低温度分别是9℃、2℃和6℃。天津厚蟹对高温也有较强的耐受能力，在0、30和50盐度水平下，分别在34℃、36℃和35℃下能耐受96h；盐度50温度38℃时，在开始的24h内无死亡，但48h后死亡率急剧上升，同样规律也出现在30和0溶液中，前者温度是39℃，后者为35℃。研究结果还表明盐度和温度的交互效应显著，二者的交互作用对天津厚蟹的存活亦有显著性影响（ P＜0.05），温度升高（从10℃到20℃再到30℃）致使其耐盐能力显著下降，而盐度的剧烈变化（从30到50或从30到0）也致使其耐温能力显著下降。%Helice tientsinensis burrow in the intertidal mudflats and estuaries especially in the high intertidal and su-pralittoral zones along the coast of northern China . The mature specimens were collected from Rongcheng , Weihai ,China .The salinity and temperature tolerance of the mud-flat crab ,Helice tientsinensis ,were investigated in the laboratory .The salinity tolerance experiment was conducted at 10℃ ,20℃ and 30℃ .Ten salinity gradients including 65 ,68 ,71 ,74 ,77 ,80 ,83 ,86 ,89 and 92 at 10℃ ,and 56 ,59 ,62 ,65 ,68 ,71 ,74 ,77 ,80 and 83 at 20℃ ,and 50 ,53 ,56 ,59 ,62 ,65 ,68 ,71 ,74 and 77 at 30℃ were respectively designed according to the results of pretests .The temperature tolerance experiment was conducted at salinities of 0 ,30 and 50 .In the low tempera-ture tolerance test ,6℃ ,7℃ ,8℃ and 9℃ at 0 salinity ,and 0℃ ,1℃ ,2℃ and 3℃ at 30 salinity ,and 3℃ ,4℃ , 5℃ and 6℃ at 50 salinity respectively designed according to the results of pretests .In the high temperature toler-ance test ,34℃ ,35℃ ,36℃ ,37℃ and 38℃ at 0 salinity ,and 36℃ ,37℃ ,38℃ ,39℃ and 40℃ at 30 salinity , and 35℃ ,36℃ ,37℃ ,38℃ and 39℃ at 50 salinity respectively designed according to the results of pretests .All treatments were triplicated with ten crabs (16 ± 2)g assigned for each replicate .The results demonstrated that He-lice tientsinensis is very tolerant of extreme salinities ,and is more tolerant of salinity than several other euryhaline crab species .The mud-flat crabs could survive 96 h in 0 solution at a temperature range of 9~34℃ .In hyper-media ,values of 96 h LS50 ,96 h survival rates of 100% and mortalities of 100% were 72.3 ,63.2 and 57.8 ,and 65 ,56 and 50 ,and 83 ,74 and 68 at 10℃ ,20℃ and 30℃ ,respectively . H elice tientsinensis tolerate a broad range of temperature condition .The minimum and maximum temperatures that the crabs survived 96 h were 9℃ ,2℃and 6℃ ,and 34℃ ,36℃ and 35℃ in solutions of 0 ,30 and 50 ,respectively .In thermal tolerance experiments , the crabs survived 24 h in solutions of 50 ,30 and 0 at 38℃ ,39℃ and 35℃ ,respectively ,but a sharp rise in mor-tality of the crabs occurred after 48h of the tolerance experiments .The results showed that the interaction of salini-ty and temperature significantly affected the survival of Helice tientsinensis ( P< 0.05 ) . Elevated temperature (range 10-30) decreased the crab's solute tolerance ,and sharp changes of the salinity (range 30-50 or 30-0) decreased the crab's temperature tolerance .
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