Context Albedo can be used to quantify ecosystem and landscape contributions to local and global climate. Such contributions are conventionally expressed as radiative forcing (RF) and global warming impact (GWI). We contextualize our results within landscape carbon production and storage to highlight the importance of changes in albedo for landscape GWI from multiple causes, including net ecosystem production (NEP) and greenhouse gas (GHG) emissions. Objective To examine the spatiotemporal changes in albedo (Δα) in contrasting managed landscapes through calculations of albedo-induced RF (RF Δα ) and GWI (GWI Δα ) under different climatic conditions. Methods We selected five contrasting landscapes within the Kalamazoo River watershed in southern Michigan USA as proof of concept. The daily MCD43A3 MODIS (V006) product was used to analyze the inter- and intra-annual variations of growing season albedo. In addition, the variations of RF Δα and GWI Δα were computed based on landscape composition and climate. Results The RF Δα (− 5.6 W m −2 ) and GWI Δα (− 1.3 CO 2eq ha −1 year −1 ) were high in forest-dominated landscapes, indicating cooling effects and CO 2eq mitigation impacts similar to crops. The CO 2eq mitigation of cropland-dominated landscapes was on average 52% stronger than forest-dominated landscapes. In the landscape with the highest proportion of forest, under dry and wet conditions CO 2eq mitigation was reduced by up to 24% and ~ 30%, respectively; in one cropland-dominated landscape wet conditions reduced CO 2eq mitigation by 23%. Conclusions Findings demonstrate that quantifying spatiotemporal changes in albedo in managed landscapes and under different climatic conditions is essential to understand how landscape modification affects RF Δα and GWI Δα and thereby contributes to ecosystem-level GWI.

中文翻译：

---

管理农业景观中反照率的时空变化：对全球变暖影响 (GWI) 的推论

上下文反照率可用于量化生态系统和景观对当地和全球气候的贡献。这种贡献通常表示为辐射强迫 (RF) 和全球变暖影响 (GWI)。我们将景观碳生产和储存中的结果置于背景下，以强调反照率变化对景观 GWI 来自多种原因的重要性，包括净生态系统生产 (NEP) 和温室气体 (GHG) 排放。目的通过计算不同气候条件下反照率诱导的RF（RF Δα ）和GWI（GWI Δα ），研究对比管理景观中反照率（Δα）的时空变化。方法 我们在美国密歇根州南部的卡拉马祖河流域内选择了五个对比鲜明的景观作为概念证明。每日 MCD43A3 MODIS (V006) 产品用于分析生长季节反照率的年际和年内变化。此外，RF Δα 和 GWI Δα 的变化是根据景观组成和气候计算的。结果 RF Δα (- 5.6 W m -2 ) 和 GWI Δα (- 1.3 CO 2eq ha -1 year -1 ) 在森林主导的景观中很高，表明冷却效果和 CO 2eq 减缓影响类似于作物。以农田为主的景观的 CO 2eq 减缓平均比以森林为主的景观强 52%。在森林比例最高的景观中，在干燥和潮湿条件下，CO 2eq 减排量分别减少了 24% 和 ~ 30%；在一个以农田为主的景观潮湿条件下，CO 2eq 减排量减少了 23%。