| Wetland ecosystem is the important component of terrestrial ecosystems and wetlands not only play an important role in maintaining regulation of local climate water aspect, in the context of global climate change, arid area alpine wetland greenhouse gas emissions, for our country and alpine wetland ecology carbon flux observation data important supplement, while providing scientific reference for the role of alpine in the global climate change in the scientific management and evaluation of arid zone in China. In this paper, the central Tianshan Bayinbuluke Swan Lake Alpine region for research, Carex main constructive species of plots for the study, the use of Li-8100 open type of soil carbon flux measurement systems, static chamber method(Li- 840 CO2 / H2 O infrared analyzer) and a closed static chamber- gas chromatography of different surface water conditions on Swan Lake alpine soil CO2 land and elimination of ecosystem CO2 and CH4, and the simultaneous determination of CO2, CH4 emissions associated environmental factors, the following conclusions:(1) Bayinbuluke Swan Lake diurnal variation of soil CO2 emission and monthly variations under different water conditions and alpine wetland showed different patterns. Soil Respiration wetlands unimodal curve, peaking at 15: 00~17: 00, ranged from 0.21~7.68 μmol·m-2·s-1. Variation of soil respiration month wetland soil CO2 respiration highest perennial water area and seasonal water area are present in June,values ??were 71.51 mg·m-2·d-1 and 40.2 mg·m-2·d-1. Perennial soil respiration maximum in the dry zone in July, is 7.32 μmol·m-2·s-1. Comparison of three different water conditions in soil respiration values??derived perennial water area is generally higher than the other two regions, compared to four month can be seen up to the perennial water area in June the highest emissions, emissions seasonal water area in August perennial drying zone in October the highest emissions and October three regional variation margin is not large.(2) Bayinbuluke Swan Lake alpine wetland ecology CO2 emissions of different water conditions change daily and monthly changes in the system showed different patterns. Wetland Ecosystem CO2 emissions diurnal variation showed a single peak curve, peaking at 15:00, ranged from 15~155.96 mg·m-2·h-1.Wetland Ecosystem CO2 emissions are highest monthly variation occurs in July, values ??were 2070.52mg·m-2·d-1 and 1356.32 mg·m-2·d-1. Comparison of three different water conditions drawn eco respiration system appears highest perennial water area. Contrast can be seen in three four month study area in July ecosystem CO2 emissions are highest.(3) Bayinbuluke Swan Lake alpine wetland ecology CH4 emissions from different water conditions change daily and monthly changes in the system showed different patterns. Depending on the moisture contrast can be seen in the performance of perennial water area source of CH4, CH4 emissions peaked in June to 4.24 mg·m-2·h-1, occurred at about 11:00 am; seasonal water area in August showed the source of CH4, other months showed CH4 sinks, seasonal water area CH4 emission peak 4.24 mg·m-2·h-1, appeared in August 11:00 am; Perennial drying zone July and October performances from 11:00 am to about 17:00 for the CH4 emissions, the rest of the performance of the absorption of CH4 June and August diurnal variation of CH4 absorption. Total CH4 emissions perennial water area> Seasonal water district> perennial drying zone.(4) Different water conditions, seasonal water wetland soil CO2 emission and 5 cm, 10 cm ground temperature and soil water content there is a significant positive correlation; Wetland Ecosystem CO2 emissions and 5cm, 10 cm ground temperature and soil moisture are there significant positive correlation(P<0.01); In addition to year-round dry zone, seasonal and perennial water area water district CO2 emission and soil water content had significant positive correlation(P <0.01); ecosystem CO2 emissions and living organisms Correlation between the amount of litter than biomass, constitute a significant correlation. Under different moisture conditions, temperature is the dominant factor determine CO2 emissions, living biomass for CO2 emissions also has some influence on the impact of CO2 emissions result from the interaction of multiple factors.(5) Under different water conditions, CH4 emissions gentle significant positive correlation(P <0.01) in the 5cm ground, and water content in the drying zone showed a significant correlation. Perennial water area positively correlated with CH4 emissions presents living biomass, and the remaining two regions with the living biomass positively correlated with litter biomass negative correlation was not significant. Moisture conditions is to determine the sources and sinks of CH4 become the dominant factor, while CH4 emissions also affected by surface geothermal and biomass. |
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