基于STICS模型的黄土高原苹果园生态系统服务评估

Abstract

苹果园在确保最大生产力的同时应适当考虑环境和自然资源，如何权衡其生态系统服务是苹果园可持续发展面临的重要问题之一。利用大田试验和STICS模型相结合的方法研究农业管理措施和气候对黄土高原苹果园生态系统服务的影响，并在此基础上对黄土高原南部半湿润区和北部半干旱区土壤氮可利用性、气候调节、水循环调节和果实生产四种苹果园生态系统服务进行了系统的评估。结果表明：（1）STICS模型均能较好模拟白水和子洲试验果园的产量、单果重、土壤含水量和蒸散发等生态系统服务指标；（2）除固碳与产量、单果重及果树相关指标是协同关系以外，其他生态系统服务之间都是权衡关系；（3）对于各管理措施下的果园平均服务标准值，秸秆覆盖（0.67） > 地布覆盖（0.52） > 清耕（0.30），充分灌溉（0.56） > 轻度亏缺灌溉（0.44） > 重度亏缺灌溉（0.30），其中秸秆覆盖和充分灌溉的果园服务概况最佳，地布覆盖和轻度亏缺灌溉的果园服务概况较相似且最平衡；（4）地布覆盖和轻度亏缺灌溉管理措施缓和权衡作用的效果优于其他管理措施。综上所述，STICS模型能够较好的量化果园生态系统服务概况，农业管理措施是果园生态系统服务强有力的驱动因子。;Apple orchards face the major challenge of ensuring maximal productivity with due consideration for the environment and natural resource. How to balance its ecosystem services is one of the important issues facing the sustainable development of apple orchards. The field experiment and the STICS model were used to study the impacts of agricultural management and climate on the ecosystem services of apple orchards in the Loess Plateau of China. And on this basis, four apple orchard ecosystem services including soil nitrogen availability, climate regulation, water circulation regulation,and fruit production were systematically evaluated in the south semi-humid and north semi-arid regions of the Loess Plateau of China. This model was parameterized by using data collected on two experimental apple orchard sites under irrigating and mulching management in the Loess Plateau. The results showed that: (1) the STICS models could well simulate the ecosystem service indicators such as yield, fruit mass, soil water content, and evapotranspiration of the Baishui and Zizhou experimental orchards. (2) Except for the synergies between carbon sequestration and yield, fruit mass and fruit-related indicators, there is a trade-off relationship among other ecosystem services. The contribution of carbon allocaton to fruit in sequestrated carbon was considerable. Nitrogen absorption, impacted by mulch and irrigation, was a major driver of these ecosystem service relationships. (3) For the average service standard value of the orchard under various management measures, straw mulching (0.67) > film mulching (0.52) > clearing cultivation (0.30), comfort irrigation (0.56) > low water stress irrigation (0.44) > high water stress irrigation (0.30). The service profile of the orchard with straw mulching and comfort irrigation were the best. And the service profile of the orchard with film mulching and low water stress irrigation were similar and the most balanced, showing higher yield, fruit mass and soil water content but lower N₂O emission. (4) The effect of mitigating trade-offs of straw mulching and low water stress irrigation are better than other management measures, and these two apple orchards are the most ideal orchards. In summary, the STICS model can quantify orchard ecosystem services profiles well, and agricultural management is a powerful driving factor of orchard ecosystem services.