论文部分内容阅读
四、资源变动的主要因素通常,亲鱼与所产生的后代数量在一定水平之下呈正相关,如果资源急激持续地增加或减少,其正常的亲子关系就不复存在,而把握其关系的关键在于成活条件。也就是说当某一年份成活率特别好或特别坏,或者年成活力持续恶化的情况下应推倒这种关系。因此,当资源呈现到某一水平以后的正常的亲子数量的正相关就会变为负相关。同时,由于成活率恶化而资源量转入减少趋势。这大概与资源的长期变动有关系。但是认
Main Factors of Resource Change Normally, the number of pro-offspring and the number of progeny produced is positively related to a certain level. If the resources are continually increased or decreased, the normal parent-child relationship ceases to exist, and the key to grasping the relationship lies in Survival conditions. That is to say, the relationship should be overturned when the survival rate is particularly good or particularly bad in a particular year, or the deteriorating annual viability. Therefore, the positive correlation between the number of normal parents after the resource has been rendered to a certain level becomes negative. At the same time, the amount of resources transferred into a declining trend due to the deteriorating survival rate. This is probably related to long-term changes in resources. But recognize