کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
88961 159328 2009 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Different response to environmental factors and spatial variables of two attributes (cover and diversity) of the understorey layers
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک بوم شناسی، تکامل، رفتار و سامانه شناسی
پیش نمایش صفحه اول مقاله
Different response to environmental factors and spatial variables of two attributes (cover and diversity) of the understorey layers
چکیده انگلیسی

We investigated the relationships among the vertical layers of a temperate forest and the power of environmental and spatial factors to explain the variation in two attributes of shrub and herbaceous layers: cover and diversity. In the study site, 102 square plots with sides of 20 m were established in a stratified random design. Among the environmental factors we studied overstorey related factors, soil attributes and topographic related variables. To use the space as an explanatory variable, we applied the Principal Coordinates of Neighbourhood Matrices method. Variation partitioning with regression analyses was used to discover which variables better explained variation in cover and diversity within the shrub and herbaceous layers. The spatial patterns displayed by cover and diversity in the shrub and herbaceous layer were more similar between both layers than within the same layer. Along the same lines, the amount of variance explained by all the environmental (overstorey, soil and topography) and spatial variables together was higher in the models of cover than in those of diversity. The differences in the explained variation were primarily due to the higher spatial fraction in the models of cover. In general, shrub and herbaceous cover was higher on southern slopes with a more diverse overstorey, high values of soil temperature and low values of litter cover. Otherwise, higher values of shrub and herbaceous diversity were found on steep slopes with low values of leaf litter cover. However, while higher values of shrub diversity were found on southern slopes, herbaceous values were more patchily distributed. The differences in the amount of variation explained by the spatial variables in both attributes (cover and diversity) indicate their different spatial arrangement at the scale which we considered. While values of cover were more continuous in space, those of diversity showed a patchy distribution of higher values. The presence of this spatial component could be interpreted as the importance of seed dispersal or unmeasured environmental variables. The results indicate that the lack of management in temperate forests allows species movement in a heterogeneous environment favouring higher values of cover and diversity in the understory layers.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Forest Ecology and Management - Volume 258, Issue 7, 15 September 2009, Pages 1267–1274
نویسندگان
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