کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6536852 1420852 2018 13 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Extremely dry environment down-regulates nighttime respiration of a black spruce forest in Interior Alaska
ترجمه فارسی عنوان
محیط بسیار خشکی تنظیم تنفس شبانه یک جنگل سیاه در سیاه آلاسکا را تنظیم می کند
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علم هواشناسی
چکیده انگلیسی
In the face of increasing temperature at high latitudes, ecosystem respiration (RE) is a key to determining sink and source dynamics of a boreal forest. In this paper, we analyzed four-year RE data obtained in an open black spruce forest-a typical boreal forest ecosystem with permafrost in Interior Alaska. RE measured as nighttime CO2 effluxes for both the ecosystem and the forest floor were clearly situated along the exponential temperature-dependent curve, except for the data obtained in extremely dry conditions in mid-summer. More than 93 % of RE data measured at nighttime with high vapor pressure deficit (VPD > 400 Pa) were lower than the values predicted from the temperature-dependent curve. Consequently, the year 2013 (with an unusually dry summer) had a 15 % lower amount of annual RE than that could be expected from the temperature-dependent curve without considering the effect of high VPD. The suppression of RE under dry conditions was also related to decreases in soil moisture and net ecosystem productivity. Finally, assuming daytime RE could be extrapolated from the temperature-dependent curves, annual daytime RE estimated with the effect of high VPD was decreased by up to 62% from RE estimated without the VPD effect. The down-regulation of RE presented in this study postulates a possible negative feedback for the carbon budget of boreal forests in response to climate warming.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Agricultural and Forest Meteorology - Volume 249, 15 February 2018, Pages 297-309
نویسندگان
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