Determining And Estimating Perturbation Effects Of Farmland Consolidation Projects On The Carbon Cycle Of Farmland Ecosystem

Global warming brought about by greenhouse-gas emissions,has garnered attention on a global scale.Research on the carbon cycle of terrestrial ecosystem has become an important part of the research on global climate change.As an important component of the terrestrial ecosystem,farmland ecosystem widely distributed,is not only a carbon source,but also an important carbon sink.Farmland ecosystem is a complex ecosystem include natural and social factors,the carbon cycle of farmland ecosystem is significantly affected by land-use activities of land patterns,so research on perturbation by human activities to farmland ecosystem carbon cycle is in hotspot.Currently,land consolidation has become an important platform for regional land use structure adjustment and the way of improving the level of land use.Farmland consolidations as the main types of land remediation,had promoted the increase of arable land,improved the regional agricultural infrastructure and enhanced the agricultural production capacity by the implementation of engineering and ecological measures.Agricultural land improvement project is often carried out as a carrier.On the other hand,farmland consolidation projects a significant disturbance to the carbon cycle of farmland ecosystem.Firstly,adjustment of land use structure such as plots merge and leveling cause changes in regional carbon stocks.Secondly,engineering technology brings the increase of carbon emissions owe to the material inputs and energy consumption.Thirdly,agricultural production capacity and production changes affect the strength of carbon sources and carbon sinks.However,the current study around the insufficient of farmland consolidation to the carbon cycle of farmland ecosystem,limiting the further development of low-carbon consolidation projects.Therefore,the paper attempt from different angle analyses the disturbance mechanism,include about the implementation of engineering,adjustment of land use structure and the change of agricultural productivity based on the theory of carbon cycle of farmland ecological and low-carbon agriculture.On this basis,building a carbon effect accounting methodology,the content includes the engineering carbon perturbation effects,the carbon perturbation effects of structural adjustment,and the carbon perturbation effects of Enhance efficiency.Finally,based on partition of agricultural consolidation projects,selecting the typical agricultural consolidation projects,the paper empirical the analysis results for Accounting,and propose measures to build the regional low-carbon agricultural consolidation projects.Results showed that:(1)Carbon emissions per unit area was about 0?2 t/hm2 owe to the implementation of the project,carbon sinks per unit was about 0?1 t/hm2,overall,carbon emissions per unit is greater than the carbon sinks per unit quantity;Irrigation projects is the largest carbon emissions engineering,carbon emissions of project was significantly affected by regional climate,topography,hydrology and other natural and geographical conditions;some materials or energy,such as steel,cement and diesel fuel is a major source of carbon emissions,the effect of Shelterbelts reducing carbon emissions is remarkable.(2)Carbon stocks in the project area were small changes in the short term.After the third year of implementation of the project,carbon stocks per unit area appeared significant increase,the growth rate is about 16%-23%growths.After fifth year of implementation of the projects,the growth rate is about 0%-3%growths,carbon stocks tend to be stable;the growth of Arable land and soil carbon density of arable land in the project area is the main reason for the increase in carbon stocks.(3)The project have an impact on carbon sinks significantly,the annual net carbon sinks reduce sharply,the reduce rate of is about 45%-55%in project implementation period.After the implementation of the project,the annual net carbon sinks increased rapidly,the rate of is about 110%-150%,but in the long-term after implementation of the project,project annual net carbon sinks growth slowed,the rate is about 5%-11%;crop harvests have a significant impact on the annual crop yields in the project area,showing a significant geographic differentiation on the annual net carbon sinks,crop carbon sink level showed significant regional differences,improvement of agricultural infrastructure and crop yields growth is the important factor affecting the carbon sinks.