Holomuzki J R
Department of Zoology, Arizona State University, 85287, Tempe, AZ, USA.
Oecologia. 1986 Dec;71(1):142-148. doi: 10.1007/BF00377334.
Survivorship and growth of larval tiger salamanders, Ambystoma tigrinum nebulosum, in the White Mountains of east-central Arizona were compared in six microhabitats using field enclosures during summers, 1983-85. Microhabitats were vegetated and nonvegetated shallows, surface, middle, and bottom horizontal layers of limnetic areas, and the vertical limnetic water column. Initial enclosure densities (0.025 larvae per 1) were identical among microhabitats. Three enclosures were placed in each microhabitat in two ponds. Larval survivorship and growth were usually greatest in vegetated shallows in lowest in middle and bottom limnetic enclosures, despite several population dieoffs. Lower fitness, as reflected in survivorship and growth, in these latter enclosures was correlated with lower food levels, temperatures, and oxygen concentrations in deeper limnetic areas. Relative fitness varied greatly between years while food levels, temperatures, and oxygen concentrations within microhabitats remained relatively constant indicating additional factors affected fitness. Disparities in fitness between microhabitats apparently affect habitat use patterns of larvae.
1983 - 1985年夏季，利用野外围栏在亚利桑那州中东部白山的六个微生境中，对虎纹钝口螈（Ambystoma tigrinum nebulosum）幼体的存活和生长情况进行了比较。微生境包括有植被和无植被的浅水区、湖泊区域的表层、中层和底层水平层以及湖泊垂直水柱。各微生境的初始围栏密度（每1个围栏中有0.025只幼体）相同。在两个池塘的每个微生境中放置了三个围栏。尽管有几次种群死亡，但幼体的存活和生长通常在有植被的浅水区最高，在湖泊中层和底层围栏中最低。在这些较深的湖泊围栏中，较低的适合度（以存活和生长来反映）与较深湖泊区域较低的食物水平、温度和氧气浓度相关。各年份之间相对适合度差异很大，而微生境内的食物水平、温度和氧气浓度保持相对恒定，这表明还有其他因素影响适合度。微生境之间适合度的差异显然会影响幼体的栖息地利用模式。
