宁南山区少免耕条件下马铃薯-蚕豆间作体系温室气体排放的影响机制

It is very important to reveal the influence mechanism of greenhouse gas emissions in specific farmland ecosystems for the implementation of emission mitigation measures. Based on the potato-broad bean intercropping system in the south Ningxia loess hilly region of Northwest China, the field experiment will be conducted to study the seasonal variation of greenhouse gas emissions, net global warming potential, soil physical and chemical properties, the abundance and diversity of soil microbial, the crop growth and its nutrient content under different tillage (conventional moldboard plowing tillage, sub-soiling tillage, no tillage) and intercropping systems (potato-faba bean intercropping system, potato, faba bean) by using some technologies such as life cycle assessment, molecular biotechnique, static box-gas chromatography. Accordingly, the project is objective to (i) study the seasonal variation of greenhouse gas emissions, total emission and net greenhouse warming potential under different tillage treatments and intercropping systems, (ii) classify the influence mechanism of greenhouse gas emissions by measuring the variation of soil properties such as soil physical and chemical properties, the abundance and diversity of soil microbial, and (iii) understand preliminary the impact mechanism of crop growth on greenhouse gas emissions by studying the effect of different tillage and intercropping systems on the crop growth and its nutrient content. Eventually, these results will provide the theoretical basis and scientific guidance for achieving the sustainable production of potato in the south Ningxia loess hilly region of Northwest China.

揭示特定区域农田生态系统温室气体（CO2、N2O、CH4）排放过程的影响因素和调控机制，对于该区域正确实施气候变暖减缓应对措施具有重要意义。本项目针对宁南山区少免耕条件下马铃薯-蚕豆间作体系，拟通过大田定位试验，利用生命周期评价法、分子生物学、静态箱-气相色谱等方法系统研究土壤温室气体季节排放规律、农田净温室效应、土壤理化和生物性状、土壤微生物多样性、作物生长及养分含量对不同耕作（传统翻耕、深松耕、免耕）和间作模式（马铃薯-蚕豆间作、马铃薯单作、蚕豆单作）的响应：（1）明确耕作和间作模式下土壤温室气体季节排放及农田净温室效应的差异；（2）揭示耕作和间作模式下土壤性状对土壤温室气体排放的调控机制；（3）明确耕作和间作模式下作物地上、地下部生长及养分含量的差异，初步阐明作物生长对土壤温室气体排放的影响机制。研究结果为构建宁南山区马铃薯高产、生态、可持续的耕作方式和间作模式提供科学依据。

通过大田定位试验，系统研究土壤呼吸速率、土壤酶活性季节变化规律、作物产量对三种不同耕作措施（传统耕作（CT）、旋耕（RT）、免耕（NT））和间作模式（马铃薯单作（P）、马铃薯蚕豆间作（PB）和蚕豆单作（B））的响应。结果表明：耕作措施和间作模式显著影响马铃薯生育期土壤呼吸速率；耕作措施和间作模式显著影响土壤酶活性（尿酶、蔗糖酶、磷酸酶和过氧化氢酶）、土壤全氮含量和有机碳含量；作物产量在RTP和NTP处理下马铃薯产量最高。该结果为构建黄土高原马铃薯高产、生态、可持续的耕作方式和间作模式提供科学依据。