A hybrid land-water-environment model for identification of ecological effect and risk under uncertain meteorological precipitation in an agroforestry ecosystem

• Published in: The Science of the total environment 2018-08, Vol.633, p.1613-1628
• Main Authors: Zeng, Xueting, Li, Tienan, Chen, Cong, Si, Zhenjiang, Huang, Guohe, Guo, Ping, Zhuang, Xiaowen
• Format: Article
• Language: English
• Subjects: Agriculture-forest; Ecological function; Fuzzy-stochastic programming with risk analysis; GR3 simulation technique; Sustainable land-water-environment plan; Uncertainty
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2018.03.224

In this study, a hybrid land-water-environment (LWE) model is developed for identifying ecological effect and risk under uncertain precipitation in an agroforestry ecosystem. A simulation-based fuzzy-stochastic programming with risk analysis (SFSR) method is used into LWE model to reflect the meteorological impacts; meanwhile, it also can quantify artificial fuzziness (e.g., risk attitude of policymaker) and natural vagueness (e.g., ecological function) in decision-making. The developed LWE model with SFSR method is applied to a practical agroforestry ecosystem in China. Results of optimized planting scale, irrigative water schedule, pollution mitigation scheme, and system benefit under changed rainfall, precise risk-adoption and vague ecological function are obtained; meanwhile their corresponding ecological effects and risks are analyzed. It found that current LWE plans could generate massive water deficits (e.g., 23.22×106m3 in crop irrigation and 26.32×106m3 in forest protection at highest) due to over-cultivation and excessive pollution discharges (e.g., the highest excessive TP and TN discharges would reach 460.64 and 15.30×103 ton) due to irrational fertilization, which would increase regional ecological risks. In addition, fifteen scenarios associated with withdrawing cultivation and recovering forest based on regional environment heterogeneity (such as soil types) have been discussed to adjust current agriculture-environment policies. It found that, the excessive pollution discharges (TN and TP) could be reduced 12.95% and 18.32% at highest through ecological expansions, which would generate higher system benefits than that without withdrawing farmland and recovering forest. All above can facilitate local policymakers to modulate a comprehensive LWE with more sustainable and robust manners, achieving regional harmony between socio-economy and eco-environment. [Display omitted] •A land-water-environment (LWE) model is built to identify ecological effect and risk.•A SFSR method is developed to handle uncertainties in an agroforest ecosystem.•The results can reflect tradeoff between irrigative development and forest protection.•The reforestation results under varied cases can avail to adjust current LWE polices.•The detections can help to produce sustainable strategies for regional sustainability.