Inlfuence Analysis Of Soil Respiration Of Tree Planting On Desert Shrubs Forest Region

Arid region is more sensitive to climate change special and importantgeographical unit, the study of arid region of soil respiration and its influencingfactors for in-depth understanding of the global carbon cycle is extremely important.This paper using LI-8100automatic soil carbon flux measurement system, in April,May, July and October,2011, in the Karamay energy saving project area of populuscarbon sink forest, selected samples in Xinjiang Populus,Russia Populus and desertshrubs area for soil respiration rate and the monitoring of the main environmentalfactors, analyzed each plant communities soil respiration rate differences for airtemperature, soil temperature and humidity response, ultimately reveal the waterdeficit, the barren soil of the desert shrub forest temporal and spatial variation of soilrespiration,provide the basis of experimental data for global carbon cycle research.The main conclusions are as follows:(1) For desert shrubs, generally peak times during the day appear from10:00to17:00, valley times appear in20:00,1:00,7:00. For artificial forest region aboutXinjiang Populus and Russia Populus, generally peak times during the day appearfrom10:00to17:00, valley times appear from20:00¹:00. Basically showing a singlepeak curve.(2) Desert250meters,desert500meters, Xinjiang Populus and Russia Populus,daily average CO₂flux respectively for-0.08,-0.33,0.16,0.03μmol·m^-1s^-2,-0.14,-0.02,0.02,-0.003μmol·m^-1s^-2,1.43,2.4,0.45,0.4μmol·m^-1s^-2,1.02,0.22,0.55,0.34μmol·m^-1s^-2in April, May, July and October. Annual soil carbon emissions is98.7gC·m^-2·a^-1,88.38gC·m^-2·a^-1,446.82gC·m^-2·a^-1,202.2gC·m^-2·a^-1in turn. Artificialforest region soil CO₂flux peak, valley, daily average was greater than the desertshrubs area in April, May, July and October. Soil respiration in monthly carbonemissions and the estimated annual carbon emissions of artificial forest region weregreater than the desert shrubs. (3) The near-surface temperature in April, May, July and October of artificialforest region were less than the desert shrubs. The highest Q₁0value of artificial forestregion was greater than the desert shrubs. The soil respiration rate and thenear-surface temperature, soil temperature and humidity of artificial forest region isbetter than the correlation of the desert shrubs.(4) The soil respiration rate related most significantly with the soil temperatureand humidity of soil depths on desert shrubs. In artificial forest region soil respirationrate of Xinjiang Populus have relevance with each layer of soil temperature andhumidity; Soil respiration rate of Russia Populus related most significantly with thesoil temperature and humidity of soil shallow on desert shrubs. Comprehensiveconsideration of the relationship between soil temperature-humidity and soilrespiration rate were greater than consider alone of the relationship between soiltemperature or humidity and soil respiration rate.(5) The soil organic carbon content, soil organic carbon density and soil organiccarbon reserves of artificial forest region are greater than the desert shrubs. Andcarbon sequestration capacity of Russia Populus is greater than Xinjiang Populus。The conclusion shows that, reforestation in the desert will increase soil CO₂emission rate, than increasing the annual soil respiration, can significantly enhancesoil organic carbon storage, have a significant role to improve the soil environmentand quality of ecologically fragile areas.