农用地整理对碳储量和粮食产能的影响

农用地整理对区域生态系统的空间格局和功能产生的影响需要持续不断的予以关注和调节。该文以福建省建溪流域为例,采用碳储量多源模型和耕地生产潜力模型估算了建溪流域的碳储量和粮食产能,分析了区域尺度农用地整理对碳储量和粮食产能的影响。研究表明:与2010年相比,2016年碳存储总量降低了38.28×10~6 t,为369.29×10~6 t;整理区以1.41%的土地贡献了整个建溪流域1.70%的碳储量减少量,农用地整理对建溪流域生态系统的固碳服务有负作用;2016年建溪流域的粮食产能提高了10.83×10~4t,为124.46×10~4t;农用地整理项目区占建溪流域耕地面积的14.61%,贡献了20.87%的粮食产能提高值,有效提高了建溪流域耕地的粮食产能。农用地整理所产生的碳效应不容忽视,在农用地整理中需要注重生态措施的运用。

Effects of agricultural land consolidation on carbon storage and grain productivity

Agricultural land consolidation is one of the largest human activities in China with lots of impacts on ecological environment. Ecosystem services are the basis for human survival and development. It is of great significance to explore the impacts of agricultural land consolidation on regional ecosystem services. This study would promote the balance, efficiency and stability of the ecosystem services in the agricultural land consolidation area. This research took Jianxi River Basin which in Fujian province as case study area. The data used in this paper were remote sensing data, the agricultural land consolidation project data, land use data, soil type map and so on. Carbon storage ecosystem services in the Jianxi River Basin were estimated by using the multi-source model of carbon storage. And crop production ecosystem services in the Jianxi River Basin were estimated by using the potential productivity model of cultivated land. Based on the comparative analysis, the effects of agricultural land consolidation on two ecosystem services were studied. The research showed that compared with 2010, total carbon storage decreased by 38.28×106t in 2016. The total carbon storage in 2016 was 369.29×106 t. The area of agricultural land consolidation project accounted for 1.41% of the area of the Jianxi River Basin. And the project area contributed 1.70% to the decrease in carbon storage. This indicated that agricultural land consolidation has negative effects on carbon storage services in the ecosystem of Jianxi River Basin. The carbon effect produced by agricultural land consolidation should not be neglected. Compared with 2010, the total crop production service in Jianxi River Basin increased by 10.83×104t in 2016, reached to 124.46 ×104t. The area of agricultural land consolidation project accounted for 14.61% of cultivated land area of the Jianxi River Basin. And the project area contributed 20.87% to the increase in crop output. This indicated that agricultural land consolidation has effectively improved the crop production services of cultivated land in the Jianxi River Basin. It is necessary to pay attention to the application of ecological measures in agricultural land consolidation. According to the research results that carbon storage services will be reduced by agricultural land consolidation, and three suggestions are put forward. 1) If the agricultural land consolidation measures would do great damage to the cultivated soil, measures such as topsoil stripping and backfill and guest soil should be adopted to protect the carbon sequestration capacity of the soil. Planting green manure and returning straw to field is also an effective biological measure to increase soil carbon sequestration. 2) Attention should be paid to the construction of ecotype ditches and field roads, and new environment friendly materials such as environment friendly field sand stone pavement additive, soft slope protection material, heavy metal passivating agent, water retaining and fertilizer agent and so on are used to reduce the loss of organic carbon storage caused by pavement hardening and excessive coagulation. 3) Strengthen the management and protection of agricultural land consolidation. Intercropping rotation system and farm manure should be used to increase the carbon storage of cultivated land through later management and protection.