全球农作物对大气CO2及其倍增的吸收量估算

THE ESTIMATION ON CROP ABSORBING CO2 UNDER CURRENT AND DOUBLE CO2 CONDITIONS IN THE WORLD

中文关键词:  作物  CO₂倍增  CO₂吸收量  估算

英文关键词:Crop  CO₂ double  Absorbing CO₂  Estimation

中文摘要:

      根据农作物产量资料(FAO1992年),计算出中国和全球各种作物对CO₂的吸收总量分别为5.5×10⁸t/aC和28.9×10⁸t/aC.同时以不同CO₂浓度下小麦、玉米、大豆等全生育期光合速率实验数据直接计算的C吸收量为对照,与相应的中国产量资料计算结果比较,两者相差2.6%.从而进一步依据作物对CO₂倍增反应诊断实验结果,推算出大气CO₂浓度比目前倍增(700ppm)条件下,中国和全球农作物吸收CO₂总量将增长21%-26%,分别为6.6×10⁸t/a-6.9×10⁸t/a和34.1×10⁸t/a-36.2×10⁸t/aC.研究还表明,单位面积作物年吸C量全球(3.2t/(hm²·8))比中国(4.2t/(hm²·a))低25.4%,而且C₄作物普遍高于同类C₃作物.

英文摘要:

      The CO₂ obsorption from crops have been estimated on the basis of crops production data (FAO 1992).It is about 550 million t/aC in China and 2890 million t/aC in the world.And making use of photosynthetic experimental data for wheat,corn and soybean in all growing seasons to calculate absorption of C directly.It shows that there is 2.6% error between estimation and calculation.Thereby according to experimental resups of crop response to doubling CO₂,crops absorb CO₂ will increase 21%-26% under doulbing CO₂ concentration condition(700ppm compared with 350ppm),that is,the total CO₂ absorption from crops will be 660-690 million t/aC in China and 3410-3620 million t/a C in global world.Additionally,this study presents crops absorb C per planting area is 4.2t/(hm²·a) in China.It is 25.4% more than mean level of the world (3.2t/hm²·a),and crop species C₄,is more than C₃ generally.