| Terrestrial ecosystem carbon storage and it's changes play a very important role in the global carbon cycle and atmospheric CO2 concentration changes, so it is an important issue in global climate change research. It is becoming increasingly important to assess land use/cover Correctly in the terrestrial ecosystem for assessing regional and continental carbon balance. Land use changes, mainly through natural vegetation changing into farmland or grazing, may influence many natural phenomena and ecological processes, result in significant changes in soil properties. Accurately assessing soil organic carbon storage and it's changes caused by human activity in regional scale are necessary, especially research based on a large number of carbon density data of field measurement. This will provide us with a good understanding of the future terrestrial ecosystem-atmosphere carbon flow basis. Land degradation is a hot issue in carbon cycle study. Daqing is soil degradation typical area, thus this paper used the MSS multi-spectral data in 1978, TM data in 1988,1992,1996,2001, Chinese resources satellite data in 2008, the second soil general survey data and field soil experiment datas in 2009, studied on land use/cover dynamic changes, vegetation carbon storage dynamic changes, soil carbon and nitrogen storage dynamic changes, land cover soil carbon and nitrogen reserviors and their impact factors, vegetation and soil carbon/nitrogen storage dynamic changes forecast, respectively in Daqing. The results show:Arable having always occupied the first place in various land cover type areas, Daqing's woodland showed an increasing trend year by year during 1978-2008, arable and grassland were main land cover types which changed into woodland. Eco-environmental effects caused by land cover dynamic change in Daqing expressed as:grassland degradation, marshland retreat, desertification, salinification and basification. Grassland changing into saline and alkaline land and arable drived land cover changes, caused eco-environmental effects. Dramatic adjusting in grassland was the main line of land cover dynamic changes in the study area. Oilfield development process drived land cover structure changes in this region. The stable demand of agricultural production and management were the direct cause of continuous arable increasing. Blind land reclamation, overgrazing and the negative effect of a number of water conservancy projects intensified land cover transfer process.Vegetation carbon densities of arable, woodland, grassland and marshland in Daqing were 0.57 kg·m-2,5.70 kg·m-2,0.129 kg·m-2 and 0.41 kg·m-2, respectively. The average vegetation carbon densities in Daqing were 0.58 kg·m-2 in 1978 and 0.67 kg·m-2 in 2008. Vegetation carbon storages were 9.38×106t in 1979 and 10.40×106t in 2008, vegetation carbon storage increased 1.02×106 t in 30 years period, was "carbon sequestration". Daqing's average vegetation carbon density is lower than Chinese average level. The average soil carbon/nitrogen densities in Daqing were 9.26±1.73 kg·m-3 and 0.62±0.17 kg·m-3 in 1979,8.18±1.65 kg·m-3 and 0.37±0.11 kg·m-3 in 2009, respectively. Average soil carbon/nitrogen densities decreased 1.08 kg·m-3 and 0.25 kg·m-3 in 30 years period, respectively. Daqing's average soil carbon/nitrogen densities are lower than Chinese average levels. Total soil carbon/nitrogen in Daqing were 187.19±34.95×106 t and 125.78±33.61×105t in 1979,165.28±33.30×106t and 75.52±21.48×105t in 2009, respectively. Total soil carbon/nitrogen storages decreased 21.91×106t and 50.26×105t in 30 years period, respectively, were "carbon/nitrogen source".Average soil carbon/nitrogen densities under land cover in Daqing were 8.10±2.34 kg·m-3 and 0.50±0.11 kg·m-3 in 1979,7.53±2.16 kg·m-3 and 0.33±0.16 kg·m-3 in 2009, respectively. Average soil carbon/nitrogen densities under land cover decreased 0.57 kg·m-3 and 0.17 kg·m-3 in 30 years period, respectively. Daqing's average soil carbon/nitrogen densities under land cover are lower than Chinese average levels. Total soil carbon/nitrogen under land cover were 163.68±47.34×106t and 102.00±22.55×105t in 1979,152.19±43.74×106 t and 67.44±33.23×105t in 2009, respectively. Total soil carbon/nitrogen storages under land cover decreased 11.49×106t and 34.56×105t in 30 years period, respectively, were "carbon/nitrogen source" Arable, Woodland, Grassland, Sand, Saline and alkaline land and Marshland C reservoir impact factors in Daqing were 0.07,-0.24,0.70,0.89,3.67,0.77, and their N reservoir impact factors were-0.65,-0.18,1.41,0.23,0.35,0.89, respectively.According to Markov model prediction, to 2158, arable, woodland, grassland, waters, residents and industrial mining land, sand, saline and alkaline land and marshland area proportions in Daqing will be 56.48%,5.94%,10.91%,4.08%,5.48%,0.63%,13.60%and 2.88%, respectively. During 1978-2158 in Daqing, total vegetation carbon storages will increase 5.12×106 t, total soil carbon/nitrogen storages under land cover will decrease 21.64×106t and 28.10×105t respectively, total vegetation and soil carbon storages will decrease 16.52×106t.At last, gave some proposals for establishing fair and effective land use patterns in Daqing region.Vegetation and soil carbon/nitrogen storage changes in Daqing are the result of the combined action in land cover changes and soil degradation. This calculation of soil carbon/nitrogen reservior impact factor values need further validation based on measured soil data. Markov model prediction results can provide some references to the decision-making for government departments, such as Protecting grassland and wetland, preventing further land desertification, multi-afforestation,etc.
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