This study aimed at the evaluation of the change in the effectiveness of Best Management Practices (BMPs) for agricultural pollution control in terms of reduction of nutrient loads to surface water bodies in Lithuania in the context of climate change (CC). The SWAT model was used by applying two CC representative concentration pathways (RCP4.5 and RCP8.5), three time horizons (historical – 2000–2019, mid-century – 2040–2059, and end-century – 2080–2099), and five BMPs (arable land conversion to grasslands, reduced fertilization, no-till farming, catch-crops, and stubble fields throughout winter). The most effective (with the greatest nutrient reduction) BMPs include grasslands, stubble fields, and winter cover crops. No-plough farming and reduced fertilization BMPs appear to be the least effective ones. CC would increase the potential of reduced fertilization and conversion to grasslands BMPs up to 179% and 17%, respectively for total nitrogen (TN) reduction. Regarding total phosphorus (TP), the reduction potential would increase 226% for fertilization reduction, and remain approximate for grasslands (at median −4%). Due to winter reduction of loads, no-plough stubble fields, and winter cover crops would decrease by as much as − 50%, − 12% and − 26%, respectively for TN, and − 30%, − 11%, and − 17%, respectively for TP, compared to the historical period. The greatest change would be recorded for the most extreme CC scenario (RCP8.5) and the longest time horizon (end-century). The effectiveness of BMPs (except for no-plough) for TN load reduction would increase more, and on average would become greater in agriculture dominated areas (of central-northern Lithuania) than elsewhere, although the maximum reduction values would occur in western (and in some cases eastern) Lithuania (except for reduced fertilization). This suggests the importance of the application of the measures in both areas. BMPs (except for grasslands) are expected to have relatively little effect on the overall crop yield.

本研究旨在评估在气候变化 (CC) 的背景下减少立陶宛地表水体养分负荷方面农业污染控制最佳管理实践 (BMP) 的有效性变化。特警模型通过应用两个 CC 代表性浓度路径（RCP4.5 和 RCP8.5）、三个时间范围（历史 - 2000-2019、世纪中叶 - 2040-2059 和世纪末 - 2080-2099）和五个 BMP 来使用（耕地转为草地、减少施肥、免耕耕作、收获作物和整个冬季的发茬地）。最有效（养分减少最多）的 BMP 包括草地、留茬地和冬季覆盖作物。免耕耕作和减少施肥的 BMP 似乎是最不有效的。CC 将减少施肥和转化为草地 BMP 的潜力分别提高 179% 和 17%，以减少总氮 (TN)。关于总磷（TP），减少施肥的潜力将增加 226%，并且在草地上保持近似值（中位数为 -4%）。由于冬季负荷减少，免耕留茬地和冬季覆盖作物将分别减少多达 - 50%、 - 12% 和 - 26%，TN 和 - 30%、 - 11% 和 -与历史时期相比，TP 分别为 17%。对于最极端的 CC 情景（RCP8.5）和最长的时间范围（世纪末），将记录最大的变化。BMPs（除了免耕）减少 TN 负荷的效果将增加更多，平均而言，在农业主导地区（立陶宛中北部）比其他地方更大，尽管最大减少值将出现在西部（和在某些情况下东部）立陶宛（减少施肥除外）。这表明在这两个领域应用这些措施的重要性。