Changes to land management over the last 150 years, primarily the conversion of perennial grasslands to agricultural production dominated by annual row crops, have greatly changed soil properties and reduced the soil's ability to infiltrate and store water in the soil profile. Direct near-term response at the time of conversion of an uncultivated remnant prairie to row crops is rare, especially responses that include repeated measurements on the same parcel of land and resampling of soils to a depth of 1 m to document rapid changes in soil organic carbon, nitrogen, and selected soil physical properties related to hydraulic properties. The objective of this research was to measure changes in soil chemical and physical properties after the conversion of perennial grassland to annual row-crop production. A before-and-after approach was used to compare soil properties from a 0.31-ha field in southwest Minnesota. Cultivation resulted in a negative shift in soil properties. Two years postcultivation, there was an overall reduction in soil organic carbon of 18.6 Mg ha⁻¹ for the 0–1.0 m soil profile. Infiltration rates and soil sorptivity exhibited significant decreases following cultivation. The average decrease in the mean postcultivation infiltration and sorptivity rates were 0.30 mm s⁻¹ and 0.12 mm s^−0.5, respectively. Bulk density increased on average by 0.10 Mg m⁻³ between 0–0.2 m and 0.14 Mg m⁻³ between 0.2–1.0 m. This work provided a rare glimpse of the vast shift in soil properties, which occurred when the plow ripped through virgin prairie decades ago during the massive expansion of agriculture.

中文翻译：

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草地转为作物生产后土壤性质的快速变化

过去 150 年来土地管理的变化，主要是将多年生草地转变为以一年生行作物为主的农业生产，极大地改变了土壤性质，降低了土壤渗透和储存土壤剖面中水分的能力。将未开垦的残余草原转变为行作物时的直接近期响应很少见，尤其是包括在同一块土地上重复测量和重新采样土壤至 1 m 深度以记录土壤有机质的快速变化的响应碳、氮和选定的与水力特性相关的土壤物理特性。本研究的目的是测量多年生草地转化为一年生中耕作物后土壤化学和物理性质的变化。使用前后方法比较明尼苏达州西南部 0.31 公顷土地的土壤特性。耕作导致土壤性质发生负变化。种植两年后，土壤有机碳总量减少了 18.6 毫克/公顷^-1用于 0–1.0 m 土壤剖面。栽培后入渗率和土壤吸着性显着下降。平均培养后渗透率和吸附率的平均下降分别为 0.30 mm s ^-1和 0.12 mm s ^-0.5。体积密度在 0-0.2 m 之间平均增加 0.10 Mg m ^-3 ，在 0.2-1.0 m之间平均增加0.14 Mg m ^{-3 。}这项工作提供了一个难得一见的土壤特性巨大变化的一瞥，这种变化发生在几十年前农业大规模扩张期间犁穿过原始草原时。