کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4374201 1303165 2010 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Understory cover and biomass indices predictions for forest ecosystems of the Northwestern United States
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک بوم شناسی، تکامل، رفتار و سامانه شناسی
پیش نمایش صفحه اول مقاله
Understory cover and biomass indices predictions for forest ecosystems of the Northwestern United States
چکیده انگلیسی

The understory community is a critical component of many processes of forest ecosystems. Cover and biomass indices of shrubs and herbs of forested ecosystems of Northwestern United States are presented. Various forest data were recorded for 10,895 plots during a Current Vegetation Survey, over the National Forest lands of entire Pacific Northwest. No significant relationships between the percent canopy cover and understory percent cover and biomass indices were found for the 129 ecoclasses analyzed. Disturbance time and type, and the soil characteristics significantly influenced the shrub biomass indices (p-values of <0.001, <0.001, and 0.01, respectively). Only disturbance time and type significantly influenced the shrub percent cover (p-values <0.001). There were no significant interactions between these variables. No significant differences were found for herb biomass indices and cover. Climate variables are reasonable predictors of understory cover and biomass indices. Elevation and slope are also influential: understory cover decreases with altitude, while understory biomass increases with slope. Most models showed weak predictive power (adjusted R-squared ≤ 0.27). However, robust models for the maximum/potential understory biomass indices for the forested areas in the Northwestern United States are reported (adjusted R-squared of 0.76 and 0.51 for shrubs and herbs, respectively). Overall, our study provides conceptual and statistical models for the understory of the National Forest lands of the Pacific Northwest. The results are comparable with other models for the area, suggesting that the predictions regarding understory vegetation are inherently difficult.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Ecological Indicators - Volume 10, Issue 3, May 2010, Pages 602–609
نویسندگان
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