แจ้งเอกสารไม่ครบถ้วน, ไม่ตรงกับชื่อเรื่อง หรือมีข้อผิดพลาดเกี่ยวกับเอกสาร ติดต่อที่นี่ ==>
หากไม่มีอีเมลผู้รับให้กรอก thailis-noc@uni.net.th
หากไม่มีอีเมลผู้รับให้กรอก thailis-noc@uni.net.th
Supika Vanitchung. Estimating Methane Oxidation and Nitrous Oxide Emission Potential in Forest Soils in Thailand. Master's Degree(Energy Technology). King Mongkut's University of Technology Thonburi. KMUTT Library. : King Mongkut's University of Technology Thonburi, 2008.
Estimating Methane Oxidation and Nitrous Oxide Emission Potential in Forest Soils in Thailand
Name: Supika Vanitchung
keyword:
methane oxidation
Abstract:
In situ CH4 and N2O fluxes were studied in soils of a dry evergreen (DEF), hill
evergreen (HEF), mixed deciduous (MDF), and moist evergreen (MEF) forests, as well as
acacia plantation (ARF) and com cultivation (AG) during 2003-2005. Laboratory studies
were also carried out to include kinetics of methane oxidation, diversity of methanotrophic
community and pathways of N2O productions. Results reveal that CH4 oxidation occurred
in all land use types but oxidation rate varied according to season, land use types, and
sampling spots. On one-year average basis, both DEF and ARF soils were the net CH4 sink
and the oxidation rates were significantly different from AG soil (-1.45+-0.88 and -1.17
+-0.48 mg CH4 m-2 day-1 for DEF and ARF, respectively). However, the AG soil was a net
CRt source (14.48+-48.65 mg CH4 m-2 day-1), The net methane emission in agricultural
soil was possible due to the combined effects of soil compaction and fertilizer application
(16-20-0). In forest soils, a clear zonation for active methane oxidation layer was detected
along the soil depth. Stratification of active oxidation zones coincides with the trends of
inorganic nitrogen content profile, while there was no clear distribution trend found in AG
soil. Examining kinetic coefficients of these active layers revealed that soil at DEF site had
high affinity for methane (Km of 52 ppmv) but rather low methanotrophic capacity (Vmax of
0.82 nmol-g soil-1.h-1). Soil at ARF and AG sites, on the other hand, showed low affinity
for methane (Km of 724 ppmvand 1454-2362 ppmv, respectively). Soils at AG sites were
capable of oxidizing high concentration of methane (Vmax about 10 nmol g soil-1 hr-1).
Analysis of methanotrophic community reveals that higher similarity between DEF and
ARF than between DEF and ARF to AG was found. Among forest soils, net CH4 oxidation
was observed in all forests but highest in HEF, although the differences among these soils
were not significant.
The monthly average emissions of N2O from DEF, HEF and MEF were
0.42+-0.321, 0.315+-0.656 and 0.077+-O.749 mg N2O m-2 day-1, respectively. Pathways of
N2O production in these soils were investigated by using C2H2 as a specific nitrification
inhibitor. Production rates at 30%WHC in these soils were 3.9+-0.2, 0.5+-0.06 and
0.87+-0.01 ng N2O-N gdw-1 day-1 in DEF, HEF and MEF, respectively. When increased
moisture content to 60%WHC, N2O production rate in DEF, HEF and MEF soils increased
68, 9 and 502 times to be 266+-62, 4.7+-2.5 and 437+-19 ng N2O-N gdw-1 day-1,
respectively. It is interesting that increasing soil moisture from 30 to 60%WHC only
slightly stimulated N2O production in HEF soil, 6 times higher or 4.2 N2O-N gdw-1 day-1
increasing. Prolonged incubation to 12 days revealed that N2O production in HEF soil
increased significantly, 200 times higher or 199 N2O-N gdw-1 day-1 increasing. In this soil
the rate of mineralization was highest. Therefore, the limiting step for N2O production in
this case was probably not the limited substrates but rather the activity of nitrifying
bacteria. The main production pathway of DEF and HEF is denitrification,; however in
MEF coupling of nitrification and denitrification occurred. Using the data from the native
forest sites (DEF, MEF, MDF, HEF) it was found that N2O emission rates were
significantly higher (p<0.01) during the wet season from May to October than during the
dry season from November to April. This was in contrast to methane oxidation that was
highest during dry season.
King Mongkut's University of Technology Thonburi. KMUTT Library
Address:
BANGKOK
Email:
info.lib@mail.kmutt.ac.th
Name: Amnat Chidthaisong
Role:
Advisor
Created:
2008
Modified:
2012-01-07
Issued:
2555-01-03
วิทยานิพนธ์/Thesis
application/pdf
CallNumber:
JGSEE268
eng
DegreeName: Master of Science
Level: Master's Degree
Descipline: Energy Technology
©copyrights King Mongkut's University of Technology Thonburi
RightsAccess:
ใช้เวลา
0.023415 วินาที
Supika Vanitchung
| Title | Contributor | Type |
|---|---|---|
| Estimating Methane Oxidation and Nitrous Oxide Emission Potential in Forest Soils in Thailand
มหาวิทยาลัยเทคโนโลยีพระจอมเกล้าธนบุรี Supika Vanitchung | Amnat Chidthaisong | วิทยานิพนธ์/Thesis |
| Methane uptakes and emissions in upland tropical forest and agricultural soils
มหาวิทยาลัยเทคโนโลยีพระจอมเกล้าธนบุรี Supika Vanitchung;Amnat Chidtaisong;Conrad, Ralf | บทความ/Article | |
| The method and data requirement of critical load calculation of sulphur in surface water in Thailand
มหาวิทยาลัยเทคโนโลยีพระจอมเกล้าธนบุรี Supika Vanitchung;Sirintornthep Towprayoon;Harvey, N.W | บทความ/Article |
Amnat Chidthaisong