2,4-Dichlorophenoxy Acetic Acid Mineralization in Amended Soil

Abstract

The application of municipal biosolid or liquid hog manure to agricultural soils under laboratory conditions at 20 degrees C influenced the fate of the herbicide 2,4-D [2,4-(dichlorophenoxy)acetic acid] in soil. When 2,4-D was added to soil at agronomic rates immediately after the addition of manure or biosolids to a coarse-textured soil, the percentage of 2,4-D mineralized at 100 days was about 47% for both treatments, compared to only 31% for control soils without amendments. The enhanced 2,4-D mineralization as a result of amendment addition was due to an increased heterotrophic microbial activity, with the greatest increases in soil respiration occurring for soils amended with biosolids. When additions of 2,4-D were delayed for one, two, or four weeks after the amendments were applied, the additions of amendments generally reduced 2,4-D mineralization in soil, particularly for manure, indicating that the effect of amendments on enhancing soil microbial activities diminished over time. In contrast, the mineralization of 2,4-D in control soils was less dependent on when 2,4-D was applied in relation to pre-incubations of soil for zero, one, two, or four weeks. The effect of manure on decreasing 2,4-D mineralization in specific soils was as large as the effect of soil texture on differences in 2,4-D mineralization across soils. Because manure was not found to impact 2,4-D sorption by soil, it is possible that 2,4-D mineralization decreased because 2,4-D transformation products were strongly sorbed onto organic carbon constituents in manure-amended soils and were therefore less accessible to microorganisms. Alternatively, microorganisms were less likely to metabolize the herbicide because they preferentially consumed the type of organic carbon in manure that is a weak sorbent for 2,4-D.

Availability of Triazine Herbicides in Aged Soils Amended with Olive Oil Mill Waste

“…However, after 30 d of incubation, simazine dissipation was faster in the unamended soil than in the amended soil, as shown in part by the decrease in simazine mineralization in the alperujo amended soil. Similarly, Farenhorst et al reported that there was less mineralization of 2,4-D (2,4-dichlorophenoxy acetic acid) in soils amended with biosolids or with manure as compared to the original soils.…”

Sorption and mobility of dimethenamid in a volcanic soil amended with liquid cow manure

“…A significant number of works have been conducted to assess the effect of applying animal amendments to soils (Balemi, 2012;Dolaptsoglou et al, 2007;Malik et al, 2013). They mainly investigate soils with a low OM content, in which the high OM content of the amendment results in an increase in adsorption capacity and consequently a reduction in leaching (Moorman et al, 2001;Albarrán et al, 2004;Wanner et al, 2005;Farenhorst et al, 2006;Si et al, 2006;López-Piñeiro, et al, 2010). Moreover, the application of animal amendments also greatly increases the amount of DOM in the soil, modifying the herbicide adsorption process and consequently the volume of leaching.…”