Centre de Recherche Et D'innovation Sur Les Végétaux, Département De Phytologie, Université Laval, 2425 Rue de l'Agriculture, Québec, QC G1V 0A6, Canada.
Département Des Sols Et De Génie Agroalimentaire, Université Laval, 2425 Rue de l'Agriculture, Québec, QC G1V 0A6, Canada.
Sci Total Environ. 2022 Sep 1;837:155765. doi: 10.1016/j.scitotenv.2022.155765. Epub 2022 May 6.
Returning turfgrass clippings to soil (i.e., mulching) has been shown to yield many benefits, such as reducing fertilizer requirements. However, previous reports on the contribution of clippings to turfgrass fertilization varies widely, making it difficult for turfgrass managers to adjust their fertilization practices. Other potential benefits of this practice, such as soil water conservation, still need to be quantified. The objectives of this project were to measure the contribution of Kentucky bluegrass clippings to N, P and K fertilization under four different N levels and to measure the impact of clippings management on turfgrass color (NDVI), soil nutrient and water content as well as thatch accumulation. A field experiment was conducted over three years, with treatments consisting of two clipping management strategies (returned or removed) and four nitrogen levels (0, 48, 96 and 144 kg N ha -1 yr -1). Clippings were collected on every mowing date and were analyzed for N, P and K foliar content. Soil volumetric water content and NDVI were measured weekly, while thatch accumulation and soil chemical content (Mehlich-3) were assessed twice per year. Increasing N fertilization resulted in an increase in both clippings dry matter yield (DMY) and foliar N concentration. Returning grass clippings was equivalent to doubling the amount of N applied through the fertilizer and resulted in an increase in turfgrass color and soil P and K levels. For P and K, clippings contribution was more affected by their DMY than by foliar concentrations. Grass clippings did not contribute to thatch accumulation, but resulted in a consistent increase (3.9% on average) in soil volumetric water content.
将草坪草修剪物归还土壤（即覆盖）已被证明具有许多益处，例如减少肥料需求。然而，先前关于修剪物对草坪施肥贡献的报告差异很大，这使得草坪管理者难以调整他们的施肥实践。这种做法的其他潜在益处，如土壤保水，仍需要量化。本项目的目的是在四个不同氮水平下测量肯塔基蓝草修剪物对 N、P 和 K 施肥的贡献，并测量修剪物管理对草坪颜色（NDVI）、土壤养分和水分含量以及枯草层积累的影响。进行了为期三年的田间试验，处理包括两种修剪管理策略（归还或移除）和四种氮水平（0、48、96 和 144 kg N ha -1 yr -1）。每次修剪时收集修剪物，并分析叶片的 N、P 和 K 含量。每周测量土壤体积含水量和 NDVI，每年两次评估枯草层积累和土壤化学含量（ Mehlich-3）。增加氮施肥导致修剪物干物质产量（DMY）和叶片 N 浓度增加。归还草坪草修剪物相当于通过肥料施用量增加一倍，从而增加了草坪颜色和土壤 P 和 K 水平。对于 P 和 K，修剪物的贡献更多地受到其 DMY 的影响，而不是叶片浓度的影响。草坪草修剪物不会导致枯草层积累，但会导致土壤体积含水量持续增加（平均增加 3.9%）。
