Seed R
Wellcome Marine Laboratory, (University of Leeds), Robin Hood's Bay, N.Yorkshire, UK.
Oecologia. 1969 Sep;3(3-4):317-350. doi: 10.1007/BF00390381.
Growth studies in M. edulis L. have shown that rates vary considerably according to age, size and environmental conditions. This may in part be attributed to its sessile habit, being unable to move away from the variable external conditions.The use of modal length frequency distributions is somewhat limited, since with three or more year groups represented, the growth of the majority of the population is so slow that individual year classes lose their identity. Growth boxes, containing marked animals of different ages, and set out in a variety of habitats gave information regarding local and seasonal growth rates. Disturbance rings were shown to be annual, and from them growth curves have been constructed.Growth is particularly seasonal, little or none occurring during the winter. Growth rates varied considerably with a variety of environmental factors (both biotic and physical) and some of these are discussed. Variable individual growth rates, together with slow growth of the majority of animals in mixed populations, are perhaps the major factors in producing population structures typical of this species on open shores.Survivorship curves for mussels in a variety of habitats have been constructed by following the survival of groups of marked animals. Whilst high mortalities occurred in the mid and low shore, survival in the upper shore in the absence of major predators, was greatly enhanced, resulting in established populations of considerable age. Periods of maximum mortality during spring and summer could be correlated with the abundance of major predators.The almost cosmopolitan distribution of M. edulis in the N. hemisphere has been made possible by virtue of its high reproductive capacity, successful larval dispersion and wide tolerance of environmental conditions, Its patchy and apparently erratic distribution both from one shore to annother and even on the same shore, is greatly influenced by the local and seasonal abundance of major predators. Whilst the upward extension of mussels is prevented, ultimately, by physical factors (e.g. temperature, dessication), its lower limits (and absence from the shallow sub littoral on many shores) are governed essentially by predators. The upward extension of many predators such as crabs or starfish, resulting in locally intense predation, may in turn be partly influenced by the actual topography of the shore itself.
对紫贻贝的生长研究表明，其生长速率会因年龄、大小和环境条件而有很大差异。这在一定程度上可能归因于其固着习性，使其无法远离多变的外部条件。模态长度频率分布的应用存在一定局限性，因为当有三个或更多年龄组时，大多数群体的生长非常缓慢，以至于各个年龄组难以区分。在各种栖息地设置装有不同年龄标记动物的生长箱，可获取有关当地和季节性生长速率的信息。已证明干扰环是每年形成的，并据此构建了生长曲线。生长具有明显的季节性，冬季生长很少或几乎不生长。生长速率会因多种环境因素（包括生物和物理因素）而有很大变化，本文将对其中一些因素进行讨论。个体生长速率的差异，以及混合群体中大多数动物生长缓慢，可能是在开阔海岸形成该物种典型种群结构的主要因素。通过追踪标记动物群体的存活情况，构建了各种栖息地贻贝的存活曲线。虽然中潮带和低潮带出现了高死亡率，但在没有主要捕食者的高潮带，存活率大大提高，从而形成了年龄相当大的稳定种群。春季和夏季的最高死亡率时期与主要捕食者的数量相关。紫贻贝在北半球几乎遍布各地，这得益于其高繁殖能力、成功的幼体扩散以及对环境条件的广泛耐受性。其从一个海岸到另一个海岸，甚至在同一海岸的分布零散且明显不规则，这在很大程度上受到主要捕食者的局部和季节性数量的影响。虽然贻贝向上扩展最终会受到物理因素（如温度、干燥）的限制，但其下限（以及许多海岸浅海沿岸没有贻贝）基本上由捕食者控制。许多捕食者（如螃蟹或海星）向上扩展导致局部捕食压力增大，这反过来可能部分受到海岸本身实际地形的影响。
