Study on outside radiation flux of coniferous and broad-leaved mixed forest ecosystem at Dinghushan in south China

The characters of outside radiation fluxes of coniferous and broad-leaved mixed forest were studied, including the distribution of upwelling shortwave radiation (R<sub>Su</sub>), upwelling longwave radiation (R<sub>Lu</sub>), upwelling total radiation (R<sub>Tu</sub&...

Full description

Saved in:
Bibliographic Details
Main Authors: WANG Xu, ZHOU Guo-yi, SUN Ge, ZHOU Chuan-yan, WANG Chun-lin
Format: Article
Language:English
Published: Zhejiang University Press 2007-05-01
Series:浙江大学学报. 农业与生命科学版
Subjects:
Online Access:https://www.academax.com/doi/10.3785/1008-9209.2007.03.0328
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849706051670114304
author WANG Xu
ZHOU Guo-yi
SUN Ge
ZHOU Chuan-yan
WANG Chun-lin
author_facet WANG Xu
ZHOU Guo-yi
SUN Ge
ZHOU Chuan-yan
WANG Chun-lin
author_sort WANG Xu
collection DOAJ
description The characters of outside radiation fluxes of coniferous and broad-leaved mixed forest were studied, including the distribution of upwelling shortwave radiation (R<sub>Su</sub>), upwelling longwave radiation (R<sub>Lu</sub>), upwelling total radiation (R<sub>Tu</sub>), and the relationship between these components and the environmental factors. The major results were as follows: At middle and small temporal scales (≤1 month), the coefficient of variation (CV) of outside radiations fluxes were R<sub>Lu</sub>&lt;R<sub>Tu</sub>≪Rs<sub>u</sub>. In wet and dry season, the average diurnal processes of Rs<sub>u</sub> presented normal peak type curves, the processes of R<sub>Lu</sub> presented undee curve, however the R<sub>Tu</sub> presented anomalous peak type curves. Among the total energy input to the ecosystem, R<sub>Tu</sub> was the largest fraction (82.93%), which indicated that outside radiation fluxes were very important to the energy balance of ecosystem. In the total upside energy, R<sub>Lu</sub> was the largest fraction (97.36%), proving that R<sub>Lu</sub> was more important than R<sub>Su</sub> which was disagreed with the usually considering. The average daily reflect coefficient (η) was 8.3%. The regression equation between monthly η(y) and precipitation x was: y=-0.385lnx+9.3376, R<sup>2</sup>=0.6762. The main factor which influences daily η might be precipitation. The regression analysed between R<sub>Lu</sub> and temperatures, including air temperatures of different height and canopy infrared temperature of the forest ecosystem, indicated that the second layer air temperature (9 m high) had the most closely related to the true surface temperature. The being using Stefan-Boltzmann equation must be revised. In a longer temporal-scale (≥1 month), for example, there existed very obvious correlation between monthly R<sub>n</sub> and monthly R<sub>Lu</sub>, monthly R<sub>n</sub> and monthly R<sub>Tu</sub>. However, the correlation between R<sub>n</sub> and R<sub>Su</sub>, was not significant. In a shorter temporal-scale (≤1 d), this correlation is significant, it seems that the shorter the temporal-scale is, the better the correlation between R<sub>n</sub> and R<sub>Su</sub> is, indicating that the influence of temporal-scale can't be ignored in research of radiation balance.
format Article
id doaj-art-ba4361111c854488aa467c653c52f636
institution DOAJ
issn 1008-9209
2097-5155
language English
publishDate 2007-05-01
publisher Zhejiang University Press
record_format Article
series 浙江大学学报. 农业与生命科学版
spelling doaj-art-ba4361111c854488aa467c653c52f6362025-08-20T03:16:18ZengZhejiang University Press浙江大学学报. 农业与生命科学版1008-92092097-51552007-05-013332833710.3785/1008-9209.2007.03.032810089209Study on outside radiation flux of coniferous and broad-leaved mixed forest ecosystem at Dinghushan in south ChinaWANG XuZHOU Guo-yiSUN GeZHOU Chuan-yanWANG Chun-linThe characters of outside radiation fluxes of coniferous and broad-leaved mixed forest were studied, including the distribution of upwelling shortwave radiation (R<sub>Su</sub>), upwelling longwave radiation (R<sub>Lu</sub>), upwelling total radiation (R<sub>Tu</sub>), and the relationship between these components and the environmental factors. The major results were as follows: At middle and small temporal scales (≤1 month), the coefficient of variation (CV) of outside radiations fluxes were R<sub>Lu</sub>&lt;R<sub>Tu</sub>≪Rs<sub>u</sub>. In wet and dry season, the average diurnal processes of Rs<sub>u</sub> presented normal peak type curves, the processes of R<sub>Lu</sub> presented undee curve, however the R<sub>Tu</sub> presented anomalous peak type curves. Among the total energy input to the ecosystem, R<sub>Tu</sub> was the largest fraction (82.93%), which indicated that outside radiation fluxes were very important to the energy balance of ecosystem. In the total upside energy, R<sub>Lu</sub> was the largest fraction (97.36%), proving that R<sub>Lu</sub> was more important than R<sub>Su</sub> which was disagreed with the usually considering. The average daily reflect coefficient (η) was 8.3%. The regression equation between monthly η(y) and precipitation x was: y=-0.385lnx+9.3376, R<sup>2</sup>=0.6762. The main factor which influences daily η might be precipitation. The regression analysed between R<sub>Lu</sub> and temperatures, including air temperatures of different height and canopy infrared temperature of the forest ecosystem, indicated that the second layer air temperature (9 m high) had the most closely related to the true surface temperature. The being using Stefan-Boltzmann equation must be revised. In a longer temporal-scale (≥1 month), for example, there existed very obvious correlation between monthly R<sub>n</sub> and monthly R<sub>Lu</sub>, monthly R<sub>n</sub> and monthly R<sub>Tu</sub>. However, the correlation between R<sub>n</sub> and R<sub>Su</sub>, was not significant. In a shorter temporal-scale (≤1 d), this correlation is significant, it seems that the shorter the temporal-scale is, the better the correlation between R<sub>n</sub> and R<sub>Su</sub> is, indicating that the influence of temporal-scale can't be ignored in research of radiation balance.https://www.academax.com/doi/10.3785/1008-9209.2007.03.0328lower subtropical Chinabroad-leaved mixed forestoutside radiation fluxesscale effect
spellingShingle WANG Xu
ZHOU Guo-yi
SUN Ge
ZHOU Chuan-yan
WANG Chun-lin
Study on outside radiation flux of coniferous and broad-leaved mixed forest ecosystem at Dinghushan in south China
浙江大学学报. 农业与生命科学版
lower subtropical China
broad-leaved mixed forest
outside radiation fluxes
scale effect
title Study on outside radiation flux of coniferous and broad-leaved mixed forest ecosystem at Dinghushan in south China
title_full Study on outside radiation flux of coniferous and broad-leaved mixed forest ecosystem at Dinghushan in south China
title_fullStr Study on outside radiation flux of coniferous and broad-leaved mixed forest ecosystem at Dinghushan in south China
title_full_unstemmed Study on outside radiation flux of coniferous and broad-leaved mixed forest ecosystem at Dinghushan in south China
title_short Study on outside radiation flux of coniferous and broad-leaved mixed forest ecosystem at Dinghushan in south China
title_sort study on outside radiation flux of coniferous and broad leaved mixed forest ecosystem at dinghushan in south china
topic lower subtropical China
broad-leaved mixed forest
outside radiation fluxes
scale effect
url https://www.academax.com/doi/10.3785/1008-9209.2007.03.0328
work_keys_str_mv AT wangxu studyonoutsideradiationfluxofconiferousandbroadleavedmixedforestecosystematdinghushaninsouthchina
AT zhouguoyi studyonoutsideradiationfluxofconiferousandbroadleavedmixedforestecosystematdinghushaninsouthchina
AT sunge studyonoutsideradiationfluxofconiferousandbroadleavedmixedforestecosystematdinghushaninsouthchina
AT zhouchuanyan studyonoutsideradiationfluxofconiferousandbroadleavedmixedforestecosystematdinghushaninsouthchina
AT wangchunlin studyonoutsideradiationfluxofconiferousandbroadleavedmixedforestecosystematdinghushaninsouthchina