کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6537873 | 158348 | 2013 | 11 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
High-precision measurements of the methane flux over a larch forest based on a hyperbolic relaxed eddy accumulation method using a laser spectrometer
ترجمه فارسی عنوان
اندازه گیری دقیق از شار متان در یک جنگل کاشته شده بر اساس یک روش تجمع چرخشی هیپربولیک آرام با استفاده از طیف سنج لیزر
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کلمات کلیدی
شار متان، سایبان جنگل، روش تجمع چرخشی آرام آرام، آنالیز گاز مبتنی بر لیزر، دقت
موضوعات مرتبط
مهندسی و علوم پایه
علوم زمین و سیارات
علم هواشناسی
چکیده انگلیسی
The precision of current micrometeorological techniques has restricted their applications in measuring small methane (CH4) fluxes in forest ecosystems. In this study, we continuously measured CH4 fluxes using a state of the art laser-based gas analyzer and a hyperbolic relaxed eddy accumulation (HREA) method. The precision of the half-hourly fluxes was estimated at 2.93 nmol mâ2 sâ1. The HREA method also contained uncertainties associated with scalar dissimilarity of 1.26 nmol mâ2 sâ1. The precision was higher than those obtained in previous eddy covariance studies, because the HREA system did not require density fluctuation and high-frequency attenuation corrections. The observed CH4 uptake decreased with increases in soil water content during the summer months. The estimated annual methane sink was 673 mg CH4 mâ2 yrâ1 with uncertainties of ±231 mg CH4 mâ2 yrâ1. This annual methane sink increased to 868 mg CH4 mâ2 yrâ1 with the application of friction velocity (u*) filtering. The uncertainties in gap-filling, storage correction, and scalar dissimilarity were less important than the uncertainties in the u* filtering. Our technique using the HREA method is a suitable tool for measuring small CH4 fluxes in forest ecosystems, especially in remote sites where frequent maintenance is not practical.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Agricultural and Forest Meteorology - Volumes 178â179, 15 September 2013, Pages 183-193
Journal: Agricultural and Forest Meteorology - Volumes 178â179, 15 September 2013, Pages 183-193
نویسندگان
Masahito Ueyama, Yuriko Takai, Yoshiyuki Takahashi, Reiko Ide, Ken Hamotani, Yoshiko Kosugi, Kenshi Takahashi, Nobuko Saigusa,