CAJ | 학술논문

为了验证对阿拉斯加东南部温带雨林中有关栖息地关系的预测,我们于1999年和2000年8-9月以及1999年和2000年4-5月研究了亚历山大群岛加氏(鼠平)(Clethrionomys gapperi)和肯氏鹿鼠(Peromyscus keeni)种群.我们测量了26个植被和结构特征以检验林隙老龄生长林、多时代老龄生长林、采伐前壮龄(23岁)生长林和泥炭混交针叶林的丰富度与微栖息地利用的相关性.微栖息地利用随季节和栖息地而变化,但加氏(鼠平)与林下落叶灌木覆盖度的正相关最显著.肯氏鹿鼠利用的微环境的林地有较少的苔藓,但是林隙与抓获加氏(鼠平)的概率有直接关系.两种鼠在两个季节的密度与林下腐朽的倒木直接相关.春季的肯氏鹿鼠密度说明加氏(鼠平)密度变化的62%,说明肯氏鹿鼠密度变化的89%.我们的结果印证了早期对阿拉斯加东南部肯氏鹿鼠在各种栖息地尤其早期的演替林中兴旺时的研究;但偏离了西部地貌中肯氏鹿鼠种群在晚期演替针叶林中达到最高密度的普遍结论.与北美西北部其它地区的种群不同,加氏(鼠平)能持久生活在上层被砍伐的雨林板块中.泥炭针叶混交林对两种鼠的繁殖种群几乎没有贡献,因而不可能减轻对多产的老龄生长雨林大规模皆伐所造成的影响.
위료험증대아랍사가동남부온대우림중유관서식지관계적예측,아문우1999년화2000년8-9월이급1999년화2000년4-5월연구료아력산대군도가씨(서평)(Clethrionomys gapperi)화긍씨록서(Peromyscus keeni)충군.아문측량료26개식피화결구특정이검험림극노령생장림、다시대노령생장림、채벌전장령(23세)생장림화니탄혼교침협림적봉부도여미서식지이용적상관성.미서식지이용수계절화서식지이변화,단가씨(서평)여림하락협관목복개도적정상관최현저.긍씨록서이용적미배경적임지유교소적태선,단시림극여조획가씨(서평)적개솔유직접관계.량충서재량개계절적밀도여림하부후적도목직접상관.춘계적긍씨록서밀도설명가씨(서평)밀도변화적62%,설명긍씨록서밀도변화적89%.아문적결과인증료조기대아랍사가동남부긍씨록서재각충서식지우기조기적연체림중흥왕시적연구;단편리료서부지모중긍씨록서충군재만기연체침협림중체도최고밀도적보편결론.여북미서북부기타지구적충군불동,가씨(서평)능지구생활재상층피감벌적우림판괴중.니탄침협혼교림대량충서적번식충군궤호몰유공헌,인이불가능감경대다산적노령생장우림대규모개벌소조성적영향.
We studied red-backed vole Clethrionomys gapperi and Keen's mouse Peromyscus keeni populations in the Alexander Archipelago to test predictions regarding habitat relations in temperate rain forest of southeastern Alaska during August-September 1998 and 2000 and April-May 1999 and 2000. We measured 26 vegetative and structural features to correlate abundance among and microhabitat use within gap-phase old growth, multi-cohort old growth, pre-commercially thinned young (23-yr-old) growth, and peatland mixed-conifer forests. Populations of both species were higher in 1998 than 1999 and 2000. Both species used microhabitats randomly in 1998, but were highly selective in 1999-2000. Correlates of microhabitat use varied between seasons and among habitats, but C.gapperi captures were most often positively correlated with the percent cover of deciduous shrubs in the understory. Microhabitats used by P.keeni had less moss cover on the forest floor, but in gap-phase were directly related to the probability of capturing a C.gapperi. Density of both species during both seasons was directly correlated with decayed downed wood in the understory. Density of P.keeni in spring explained 62% of the variation in C.gapperi density, which in turn explained 89% of the variation in P.keeni density. Our results corroborate the findings of earlier studies that P.keeni in southeastern Alaska flourishes in a variety of habitats, especially early seral forests; but, departed from the general conclusion that C.gapperi populations in western landscapes achieve their highest densities in late-seral coniferous forests. Unlike populations elsewhere in northwestern North America, C.gapperi may be able to persist in rain forest patches where the overstory has been removed. Peatland mixed-conifer forest contributed little to breeding populations of C.gapperi or P.keeni and thus is unlikely to mitigate any impacts of broad-scale clearcut logging of productive old-growth rainforests.