ABSTRACT In humid climates, the risk of nitrate leaching and topsoil loss due to erosion is high on bare soil in the fall after potato (Solanum tuberosum L.) harvest and in the spring with snowmelt. This 2-year study (2016–2017) compared three winter cover crops. Two of these are used as cash crops (winter rye [Secale cereale L.], winter wheat [Triticum aestivum L.]), and one is a winter-killed cover crop (spring barley, Hordeum vulgare L.). They were all seeded on two dates after potato harvest (end of September or first week of October) in Prince Edward Island, Canada. The measured parameters included soil nitrate measured at different times in fall and in the following spring and summer, splash detachment, C and N contents in splashed sediments, cereal straw dry matter yield, and cereal grain yield. In both years, all winter cover crops decreased splash detachment compared with the no winter cover control, with winter rye having the greatest reduction. A similar trend was observed for C and N contents in splashed sediments. There was a trend toward lower soil nitrate following winter cover crops in comparison with bare soil, but the trend was not consistent across trials and sampling dates. Winter wheat grain yield ranged from 4.5 to 7.6 Mg ha−1, while that associated with winter rye ranged from 3.2 to 5.1 Mg ha−1. Therefore, winter cereal seeded after potato harvest can constitute a good source of revenue while mitigating the risk of soil erosion and reducing nitrate leaching in some cases.

中文翻译：

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在加拿大东部马铃薯收获后通过冬季覆盖作物提高环境绩效

摘要 在潮湿气候下，在秋季马铃薯（Solanum tuberosum L.）收获后和春季融雪后，裸土上的硝酸盐浸出和表土流失的风险很高。这项为期两年的研究（2016-2017）比较了三种冬季覆盖作物。其中两种用作经济作物（冬黑麦 [Secale creame L.]、冬小麦 [Triticum aestivum L.]），一种是冬死的覆盖作物（春大麦、Hordeum vulgare L.）。它们都在加拿大爱德华王子岛马铃薯收获后的两个日期（9 月底或 10 月的第一周）播种。实测参数包括秋季及次年春夏不同时期土壤硝酸盐含量、飞溅脱离、飞溅沉积物中C、N含量、谷物秸秆干物质产量和谷物产量。这两年，与没有冬季覆盖的对照相比，所有冬季覆盖作物都减少了飞溅脱离，其中冬季黑麦的减少幅度最大。飞溅沉积物中的 C 和 N 含量也观察到类似的趋势。与裸土相比，冬季覆盖作物后土壤硝酸盐含量有降低的趋势，但这种趋势在试验和采样日期之间并不一致。冬小麦籽粒产量范围为 4.5 至 7.6 Mg ha-1，而与冬黑麦相关的产量范围为 3.2 至 5.1 Mg ha-1。因此，在某些情况下，马铃薯收获后播种的冬季谷物可以构成良好的收入来源，同时减轻水土流失的风险并减少硝酸盐浸出。飞溅沉积物中的 C 和 N 含量也观察到类似的趋势。与裸土相比，冬季覆盖作物后土壤硝酸盐含量有降低的趋势，但这种趋势在试验和采样日期之间并不一致。冬小麦籽粒产量范围为 4.5 至 7.6 Mg ha-1，而与冬黑麦相关的产量范围为 3.2 至 5.1 Mg ha-1。因此，在某些情况下，马铃薯收获后播种的冬季谷物可以构成良好的收入来源，同时减轻水土流失的风险并减少硝酸盐浸出。飞溅沉积物中的 C 和 N 含量也观察到类似的趋势。与裸土相比，冬季覆盖作物后土壤硝酸盐含量有降低的趋势，但这种趋势在试验和采样日期之间并不一致。冬小麦籽粒产量范围为 4.5 至 7.6 Mg ha-1，而与冬黑麦相关的产量范围为 3.2 至 5.1 Mg ha-1。因此，在某些情况下，马铃薯收获后播种的冬季谷物可以构成良好的收入来源，同时减轻水土流失的风险并减少硝酸盐浸出。