CAJ | 학술논문

基于24 hm~2古田山中亚热带常绿阔叶林长期监测样地调查资料,采用Ripley的K函数点格局分析等方法,具体分析了古田山常绿阔叶林优势树种甜槠(Castanopsis eyrei与木荷(Schima superba)不同年龄阶段的空间分布格局以及它们之间的空间关联性.结果表明:两种优势物种在总体上及不同年龄阶段主要呈聚集分布,且随年龄阶段的增加,聚集程度有降低的趋势.两物种在大尺度直观上有明显的生境偏好.两种优势物种的幼树、小树与大树和老树主要呈空间负相关或无空间关联性,与中树呈空间正相关.甜槠中树与大树、大树与老树主要呈空间正相关,而甜槠的中树与老树呈空间负相关.木荷中树与大树和老树、大树与老树均呈现空间负相关或无关联.我们发现古田山优势物种通过密度制约和Janzen.Connell效应释放空间,为其他物种共存提供了条件,密度制约和Janzen-Connell效应可能是古田山样地甜槠和木荷空间格局形成的重要原因.
기우24 hm~2고전산중아열대상록활협림장기감측양지조사자료,채용Ripley적K함수점격국분석등방법,구체분석료고전산상록활협림우세수충첨저(Castanopsis eyrei여목하(Schima superba)불동년령계단적공간분포격국이급타문지간적공간관련성.결과표명:량충우세물충재총체상급불동년령계단주요정취집분포,차수년령계단적증가,취집정도유강저적추세.량물충재대척도직관상유명현적생경편호.량충우세물충적유수、소수여대수화로수주요정공간부상관혹무공간관련성,여중수정공간정상관.첨저중수여대수、대수여로수주요정공간정상관,이첨저적중수여로수정공간부상관.목하중수여대수화로수、대수여로수균정현공간부상관혹무관련.아문발현고전산우세물충통과밀도제약화Janzen.Connell효응석방공간,위기타물충공존제공료조건,밀도제약화Janzen-Connell효응가능시고전산양지첨저화목하공간격국형성적중요원인.
Aims Many mechanisms of forest pattems have been examined in tropical rain forest; however, there are only a handful of similar studies on subtropical broad-leaved evergreen forest. Our objective is to analyze the main mechanisms of distribution pattern of Castanopsis eyrei and Schima superba in GTS (Gutianshan) forest plot. Methods Based on a stem map of a 24 hm~2 permanent plot in the middle subtropical broad-leaved evergreen forest at Gutianshan National Reserve, we analyzed the distribution pattern of the dominant species C. eyrei and S. superba in saplings, juvenile trees, adult trees, large trees and old trees using spatial point pattern analysis. We also examined spatial associations among different growth stages.Important findings Castanopsis eyrei and S. superba had a clustered distribution across a range of scales (0-100 m). Saplings, juvenile trees and adult trees tended to be more clumped than big trees. Old trees tended to be somewhat more clumped than big trees. Our results suggested that the two species have obvious habitat prefer-ences at larger scales. For C. eyrei, saplings Were significantly positively associated with juvenile trees at scales ≤100 m, as were saplings and adult trees, juvenile trees and adult trees, adult trees and big trees. Generally there was no correlation between big trees and old trees at scales ≤10 m, whereas their association tended to be posi-tive at larger scales (10-100 m). Generally there were negative or no correlations between other size classes. For S. superba, the saplings Were significantly positively associated With juvenile trees at scales ≤100 m, as were saplings and adult trees, juvenile trees and adult trees. Generally there were negative or no correlations between juvenile trees and old trees, adult trees and old trees, big trees and old trees, saplings and big trees, juvenile trees and big trees, adult trees and big trees. Generally there was negative correlation between saplings and old trees at scales ≤ 20 m, Whereas their association tended to be positively at larger scales (25-100 m). These results sug-gested that dominant species facilitated coexistence of other species through emptying space for colonization of other species, which is probably attributed to density dependence or the Janzen-Connell effect. Both processes depended on species in intensity and acting time.