Broadbalk mean long-term yields of winter wheat 1852-2022

The Broadbalk experiment started in autumn 1843, and for the first eight years, the fertilizer treatments were varied, to test specific questions. From 1852 a scheme of fertilizer treatments was established, which remained largely unaltered until 1967. The mean yields are taken from this period since 1852. The yield values are means of every 10 years from 1852-1964, except for 1922-1934 during a transition period. After 1968, when modern short straw varieties were introduced, the means represent data for each variety grown, except for Hereward which has been split into two periods when the FYM treatment receiving fertiliser N in spring received either 96 kg N ha-1 (1996-2004) or 144 kg N ha-1 (2005-2012). Data for 2015 and 2020 are not included as spring wheat varieties were grown in these years as wet weather conditions in autumn and winter delaying seed sowing.

布罗德巴尔克（Broadbalk）长期肥料试验于1843年秋季启动，试验前八年通过调整肥料处理方案以验证特定科学问题。1852年起确立了一套标准化肥料处理方案，该方案在1967年前基本未作改动。本次研究的平均产量数据取自1852年起的试验周期。1852至1964年间的产量值为每10年的平均值，但1922至1934年的转型过渡期数据除外。1968年引入现代短秆作物品种后，平均产量统计对应各栽培品种的单独数据，唯有赫里沃德（Hereward）品种需分为两个统计阶段：其春季施加氮肥的农家肥（FYM, Farmyard Manure）处理组，在1996-2004年与2005-2012年分别施入96千克氮·公顷⁻¹与144千克氮·公顷⁻¹的氮肥。2015年与2020年的数据未被纳入分析，因该两年受秋冬阴雨天气影响推迟了播种，故而种植了春小麦品种。