Carbon dioxide capture and storage(CCS) has been recognized as an effective way to mitigate emission of CO2 to the atmosphere and may become a critical technology for global CO2 mitigation,however,the risk of CO2 leaking from its geologic storage will pose a potential threat to the terrestrial ecosystem,especially the near-surface terrestrial ecosystem.From the aspects of the three major components(ground water,soil and vegetation) of the near-surface terrestrial ecosystem,a review is presented of the potential impact of the leakage on the ecosystem and its process,and progresses and shortcomings of the researches,abroad and at home,in this field are summarized.On such a basis,it is indicated that the study on impacts of CO2 leakage from its geologic storage should be focused on evaluation of its impacts on farmland ecosystems,determination of threshold of tolerance of the ecosystems to the leakage,construction of an early warning system for CO2 leakage,and proposition of a system of countermeasures for the terrestrial ecosystem to avoid or mitigate disasters CO2 leakage may cause.

A field experiment was conducted in double rice area to figure out the influence of different rice straw treatments(rice straw removing +NPK,rice straw incorporated into the soil(RS)+NPK,rice straw burned in situ(BIS)+NPK) on the greenhouse gases emission from paddy fields.The results showed that RS+NPK treatment increased the CH4 emission and decreased the N2O emission significantly compared with NPK treatment,while BIS+NPK treatment reduced CH4 and N2O emission during the double rice growing season.N2O emission of RS+NPK and BIS+NPK treatments had no significant difference.CH4 emission from burning activity was equivalent to that from rice field,while N2O emission accounted for a great proportion of total N2O emission during the growing period,90.1% and 53.4%,respectively.The total GHG emission of different treatment is RS+NPKNPKBIS+NPK.A similar order was found for emission intensity(CO2 e/t grain yield).