Área de Edafología y Química Agrícola, Facultad de Ciencias - IACYS, Universidad de Extremadura, Avda de Elvas s/n, 06071 Badajoz, Spain.
Área de Producción Vegetal, Escuela de Ingenierías Agrarias - IACYS, Universidad de Extremadura, Ctra de Cáceres, 06071 Badajoz, Spain.
Sci Total Environ. 2022 Nov 15;847:157651. doi: 10.1016/j.scitotenv.2022.157651. Epub 2022 Jul 27.
Irrigation and tillage practice alternatives to conventional flooding production, with or without organic amendments, are attracting great interest to adapt rice cultivation to climate change. However, they can alter the behaviour of pesticides and their efficiency against weeds. A two-year field experiment was conducted to investigate how the environmental fate and the weed control efficiency (WCE) of bispyribac‑sodium (BS) were influenced by biochar produced from holm oak prunings (BHO) testing both the fresh and the aged effects. The treatments were: flooding irrigation and tillage (FT), sprinkler irrigation and tillage (ST), sprinkler irrigation and no-tillage (SNT), and the corresponding homologues with BHO addition (FT-BHO, ST-BHO, and SNT-BHO, respectively). Fresh BHO amendment decreased the sorption of BS onto the soil in all treatments, while, after aging, it also decreased sorption in FT-BHO (1.3-fold) but increased it in SNT-BHO and ST-BHO (1.1-fold). BHO addition reduced BS persistence under non-flooding and flooding incubation conditions, except for FT under the former condition for which t increased ≈1.5-fold in both years. The addition of BHO led to a decrease in BS leaching from 58.3 % and 44.6 % and from 70.4 % and 58.1 % in ST and FT to 50.1 % and 38.3 % and 63.6 % and 50.3 % in the homologue amended soils for the fresh and aged years, respectively. While fresh BHO addition decreased the WCE of BS in SNT-BHO, ST-BHO, and FT-BHO on average by a factor of 1.5, with aged BHO there was only such a decrease (by a factor of 1.4) in FT-BHO. The use of BHO could be effective for reducing water contamination by BS in flooding or sprinkler irrigation rice farming as long as conventional tillage is used. But it may also contribute to greatly reducing the herbicide's efficiency, although with time to allow aging, this reduction would only persist under conventional flooding production.
与常规淹水生产相比，具有或不具有有机改良剂的灌溉和耕作替代方法引起了人们极大的兴趣，以适应气候变化下的水稻种植。然而，它们可以改变农药的行为及其对杂草的防治效果。本研究进行了为期两年的田间试验，以调查生物炭（BHO）对吡嘧磺隆钠（BS）的环境行为和杂草防治效果（WCE）的影响，同时测试了新鲜和老化的效果。处理方式为：淹水灌溉和耕作（FT）、喷灌和耕作（ST）、喷灌和免耕（SNT），以及相应的添加 BHO 的同源物（FT-BHO、ST-BHO 和 SNT-BHO）。新鲜 BHO 添加剂降低了 BS 在所有处理中的土壤吸附，而老化后，它也降低了 FT-BHO 中的吸附（1.3 倍），但增加了 SNT-BHO 和 ST-BHO 中的吸附（1.1 倍）。BHO 的添加减少了非淹水和淹水培养条件下 BS 的持久性，除了在第一年 FT 条件下，BS 的半衰期增加了约 1.5 倍。BHO 的添加导致 BS 从 ST 和 FT 中的淋溶率分别降低了 58.3%和 44.6%和 70.4%和 58.1%至 50.1%和 38.3%和 63.6%和 50.3%，而在新鲜和老化的土壤中，添加 BHO 的同源物。在新鲜 BHO 处理中，SNT-BHO、ST-BHO 和 FT-BHO 中的 BS 的 WCE 平均降低了 1.5 倍，而在老化 BHO 中，仅在 FT-BHO 中降低了 1.4 倍。只要使用常规耕作，BHO 的使用就可以有效减少淹水或喷灌水稻种植中 BS 对水的污染。但是，它也可能极大地降低除草剂的效率，尽管随着时间的推移允许老化，这种减少只会在常规淹水生产下持续。
