کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4393686 1305498 2009 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Rainfall variability may modify the effects of long-term exclosure on vegetation in Mandalgobi, Mongolia
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فرآیندهای سطح زمین
پیش نمایش صفحه اول مقاله
Rainfall variability may modify the effects of long-term exclosure on vegetation in Mandalgobi, Mongolia
چکیده انگلیسی

Starting in 2005, we examined differences in vegetation for three consecutive years across an airport fence that separated heavily grazed areas from areas in which grazing had been excluded for 24 years in Mandalgobi, Mongolia. We performed repeated-measures analysis separately on two community types (dominated by Allium polyrrhizum and Achnatherum splendens, respectively) to compare the effects of fencing and year on the cover of different plant functional types. There was a significant fence × year interaction for grass cover in the Allium type (but not the Achnatherum type), due to greater cover of grasses inside the fence only when rainfall was sufficient during the growing season. The effect of grazing exclusion on perennial forb cover was confounded by a significant fence × year interaction in both types. In 2007, perennial forbs were found outside the fence, but had almost disappeared inside the fence, resulting in this interaction. Annual forbs only had much greater cover values inside the fence than outside in 2006, also resulting in a significant fence × year interaction in both community types. This study thus suggests that the high rainfall variability in arid and semi-arid rangelands may modify the effects of long-term exclosure on vegetation.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Arid Environments - Volume 73, Issue 10, October 2009, Pages 949–954
نویسندگان
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