Finnish Environment Institute, Latokartanonkaari 11, 00790 Helsinki, Finland.
Department of Economics and Management, University of Helsinki, P.O. Box 27, 00014, Finland.
Sci Total Environ. 2021 Aug 20;783:146871. doi: 10.1016/j.scitotenv.2021.146871. Epub 2021 Mar 31.
This paper introduces a framework for extending global climate and socioeconomic scenarios in order to study agricultural nutrient pollution on an individual catchment scale. Our framework builds on and extends Representative Concentration Pathways (RCPs) and Shared Socioeconomic Pathways (SSPs) at the spatial and temporal scales that are relevant for the drivers of animal husbandry, manure recycling and the application of inorganic fertilisers in crop production. Our case study area is the Aura river catchment in South-West Finland, which discharges into the heavily eutrophic Baltic Sea. The Aura river catchment has intensive agriculture - both livestock and crop production. Locally adjusted and interpreted climate and socioeconomic scenarios were used as inputs to a field-level economic optimisation in order to study how farmers might react to the changing markets and climate conditions under different SSPs. The results on economically optimal fertilisation levels were then used as inputs to the spatially and temporally explicit nutrient loading model (VEMALA). Alternative manure recycling strategies that matched with SSP narratives were studied as means to reduce the phosphorus (P) overfertilisation in areas with high livestock density. According to our simulations, on average the P loads increased by 18% during 2071-2100 from the current level and the variation in P loads between scenarios was large (from -14% to +50%). By contrast, the nitrogen (N) loads had decreased on average by -9% (with variation from -20% to +3%) by the end of the current century. Phosphorus loading was most sensitive to manure recycling strategies and the speed of climate change. Nitrogen loading was less sensitive to changes in climate and socioeconomic drivers.
本文提出了一个扩展全球气候和社会经济情景的框架，以便在单个流域尺度上研究农业营养物污染。我们的框架建立在代表性浓度路径（RCP）和共享社会经济路径（SSP）的基础上，并扩展了它们在与畜牧业、粪便再循环以及在作物生产中应用无机肥料的驱动力相关的时空尺度上的应用。我们的案例研究区域是芬兰西南部的 Aura 河流域，该流域排入富营养化严重的波罗的海。Aura 河流域的农业集约化程度高，包括畜牧业和作物生产。当地调整和解释的气候和社会经济情景被用作田间经济优化的输入，以研究在不同 SSP 下，农民如何应对不断变化的市场和气候条件。然后，将经济上最佳施肥水平的结果用作空间和时间明确的养分负荷模型（VEMALA）的输入。研究了与 SSP 叙述相匹配的替代粪便再循环策略，作为减少高牲畜密度地区磷（P）过度施肥的一种手段。根据我们的模拟结果，与当前水平相比，2071-2100 年期间 P 负荷平均增加了 18%，情景之间的 P 负荷变化很大（从-14%到+50%）。相比之下，到本世纪末，氮（N）负荷平均减少了-9%（变化范围为-20%至+3%）。磷负荷对粪便再循环策略和气候变化速度最为敏感。氮负荷对气候和社会经济驱动因素的变化不太敏感。
