Although the importance of forest margins in ecology is recognized, no study has been carried out in the Slătioara Secular Forest Reserve with reference to the variability of abiotic parameters along forest margins. W...Although the importance of forest margins in ecology is recognized, no study has been carried out in the Slătioara Secular Forest Reserve with reference to the variability of abiotic parameters along forest margins. With this study, we investigate to what extent microclimatic variables (air temperature—T_air, air humidity—H_air, soil temperature—T_soil, soil humidity—H_soil wind intensity (WIND) and photosynthetically active radiation intensity (PAR)) are correlated with the distance from the edge to the forest interior and the habitat type (forest interior, inner and outer edge and meadow) in the Slătioara Secular Forest Reserve. In order to measure these microenvironment variables we used the strip transect method, positioned perpendicular to the forest edge. Differences in the microenvironment variables considered in the analysis between the four habitat types were assessed using one-way ANOVA followed by Tukey-test post-hoc. To assess differences along transects, each of the six measurements went through a one-way ANOVA against distance to edge, followed by a Levene’s test for variances and finally a Tukey-test post-hoc. The results indicate that the values of microclimatic variables were significantly different in relation to the gradient of distance from the edge and to the habitat type (interior-exterior forest) and that edge habitats are significantly more susceptible to lower humidity, high winds, lower light and higher air temperatures than forest interior habitats. The ecological study of the edge areas in this reserve provides the basis for future research on forest dynamics and can guide conservation efforts to maintain the diversity and endemism of species in the Slătioara Secular Forest.展开更多
Three types of landscape boundary (forest/pepper field, forest/cabbage field,and forest/grassland) were selected in the arid valley of upper reaches of Minjiang River,southwestern China. On the basis of vegetation div...Three types of landscape boundary (forest/pepper field, forest/cabbage field,and forest/grassland) were selected in the arid valley of upper reaches of Minjiang River,southwestern China. On the basis of vegetation diversity, the depth of edge influence (DEI) ondifferent types of landscape boundaries was estimated using principal components analysis (PCA)method and moving split-window techniques (MSWT). The results showed that in the 5 transects, PCAmethod was able to detect the edge influence depth with 3 transects, while MSWT could explain 4transects. It is concluded that PCA and MSWT both can be used to detect the depth of edge influencewithin 50 m from the edge to the interior. Similar conclusions were drawn in the forest of eachtransect with the two methods, but no similar conclusions were drawn in the pepper field of eachtransect. Although the two methods have advantages and disadvantages respectively, they are usefultools for characterizing edge dynamics. Comparing the two methods, MSWT is more successful.展开更多
文摘Although the importance of forest margins in ecology is recognized, no study has been carried out in the Slătioara Secular Forest Reserve with reference to the variability of abiotic parameters along forest margins. With this study, we investigate to what extent microclimatic variables (air temperature—T_air, air humidity—H_air, soil temperature—T_soil, soil humidity—H_soil wind intensity (WIND) and photosynthetically active radiation intensity (PAR)) are correlated with the distance from the edge to the forest interior and the habitat type (forest interior, inner and outer edge and meadow) in the Slătioara Secular Forest Reserve. In order to measure these microenvironment variables we used the strip transect method, positioned perpendicular to the forest edge. Differences in the microenvironment variables considered in the analysis between the four habitat types were assessed using one-way ANOVA followed by Tukey-test post-hoc. To assess differences along transects, each of the six measurements went through a one-way ANOVA against distance to edge, followed by a Levene’s test for variances and finally a Tukey-test post-hoc. The results indicate that the values of microclimatic variables were significantly different in relation to the gradient of distance from the edge and to the habitat type (interior-exterior forest) and that edge habitats are significantly more susceptible to lower humidity, high winds, lower light and higher air temperatures than forest interior habitats. The ecological study of the edge areas in this reserve provides the basis for future research on forest dynamics and can guide conservation efforts to maintain the diversity and endemism of species in the Slătioara Secular Forest.
基金This work was financially supported by the Major State Basic Research Program of China (973 Program: 2002CB111506).
文摘Three types of landscape boundary (forest/pepper field, forest/cabbage field,and forest/grassland) were selected in the arid valley of upper reaches of Minjiang River,southwestern China. On the basis of vegetation diversity, the depth of edge influence (DEI) ondifferent types of landscape boundaries was estimated using principal components analysis (PCA)method and moving split-window techniques (MSWT). The results showed that in the 5 transects, PCAmethod was able to detect the edge influence depth with 3 transects, while MSWT could explain 4transects. It is concluded that PCA and MSWT both can be used to detect the depth of edge influencewithin 50 m from the edge to the interior. Similar conclusions were drawn in the forest of eachtransect with the two methods, but no similar conclusions were drawn in the pepper field of eachtransect. Although the two methods have advantages and disadvantages respectively, they are usefultools for characterizing edge dynamics. Comparing the two methods, MSWT is more successful.