An Estimate of Biogenic Emissions of Volatile Organic Compounds during Summertime in China (7 pp) |
| |
Authors: | Wang Qingeng Han Zhiwei Wang Tijian Higano Yoshiro |
| |
Institution: | (1) State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210093, China;(2) Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China;(3) Department of Atmospheric Science, Nanjing University, Nanjing, 210093, China;(4) Graduate School of Life and Environmental Science, University of Tsukuba, Ibaraki 305-8572, Japan |
| |
Abstract: | Background and Aim An accurate estimation of biogenic emissions of VOC (volatile organic compounds) is necessary for better understanding a series
of current environmental problems such as summertime smong and global climate change. However, very limited studies have been
reported on such emissions in China. The aim of this paper is to present an estimate of biogenic VOC emissions during summertime
in China, and discuss its uncertainties and potential areas for further investigations.
Materials and Methods This study was mainly based on field data and related research available so far in China and abroad, including distributions
of land use and vegetations, biomass densities and emission potentials. VOC were grouped into isoprene, monoterpenes and other
VOC (OVOC). Emission potentials of forests were determined for 22 genera or species, and then assigned to 33 forest ecosystems.
The NCEP/NCAR reanalysis database was used as standard environmental conditions. A typical summertime of July 1999 was chosen
for detailed calculations.
Results and Discussion The biogenic VOC emissions in China in July were estimated to be 2.3×1012gC, with 42% as isoprene, 19% as monoterpenes and 39% as OVOC. About 77.3% of the emissions are generated-from forests and
woodlands. The averaged emission intensity was 4.11 mgC m−2 hr−1 for forests and 1.12 mgC m−2 hr−1 for all types of vegetations in China during the summertime. The uncertainty in the results arose from both the data and
the assumptions used in the extrapolations. Generally, uncertainty in the field measurements is relatively small. A large
part of the uncertainty mainly comes from the taxonomic method to assign emission potentials to unmeasured species, while
the ARGR method serves to estimate leaf biomass and the emission algorithms to describe light and temperature dependence.
Conclusions This study describes a picture of the biogenic VOC emissions during summertime in China. Due to the uneven spatial and temporal
distributions, biogenic VOC emissions may play an important role in the tropospheric chemistry during summertime.
Recommendations and Perspectives Further investigations are needed to reduce uncertainties involved in the related factors such as emission potentials, leaf
biomass, species distribution as well as the mechanisms of the emission activities. Besides ground measurements, attention
should also be placed on other techniques such as remotesensing and dynamic modeling. These new approaches, combined with
ground measurements as basic database for calibration and evaluation, can hopefully provide more comprehensive information
in the research of this field.
Submission Editor: Prof. Dr. Gerhard Lammel (lammel@recetox.muni.cz) |
| |
Keywords: | Biogenic emissions emission inventory isoprene monoterpenes OVOC ozone precursors VOC |
本文献已被 SpringerLink 等数据库收录! |
|