Laboratory of Ecotoxicology, Institute of Environmental Sciences, University of Castilla-La Mancha, 45071 Toledo, Spain.
Coastal Plains Soil, Water & Plant Research Center, Agricultural Research Service, US Department of Agriculture, 2611 West Lucas Street, Florence, SC 29501, USA.
J Hazard Mater. 2021 Apr 15;408:124405. doi: 10.1016/j.jhazmat.2020.124405. Epub 2020 Oct 29.
We assessed the enzymatic activation of four different biochars produced from pyrolyzing swine manure and poultry litter, and by co-pyrolyzing these livestock residues with agricultural spent mulch plastic film wastes (plastichars). Enzymatic activation consisted of incubating biochars in soil inoculated with earthworms (Lumbricus terrestris), which acted as biological vectors to facilitate retention of extracellular enzymes onto biochar surface. The activity of carboxylesterase ‒a pesticide-detoxifying enzyme‒ was measured in non-bioturbed soils (reference), linings of the burrows created by earthworms, casts (feces) and biochar particles recovered from the soil. Our results revealed that: 1) biochar increased soil carboxylesterase activity respect to biochar-free (control) soils, which was more prominent in the presence of earthworms. 2) The maximum enzyme activity was found in soils amended with plastichars. 3) The plastichars showed higher enzyme binding capacities than that of the biochars produced from animal manure alone, corroborating the pattern of enzyme distribution found in soil. 4) The presence of earthworms in soil significantly increased the potential of the plastichars for enzymatic activation. These findings suggest that the plastichars are suitable for increasing and stabilizing soil enzyme activities with no toxicity on earthworms.
我们评估了由猪粪和家禽粪便热解产生的四种不同生物炭，以及通过共热解这些牲畜残渣和农业废弃的覆盖塑料薄膜废物（塑料炭）的酶促活化作用。酶促活化包括将生物炭在接种有蚯蚓（Lumbricus terrestris）的土壤中孵育，蚯蚓作为生物载体，有利于将细胞外酶保留在生物炭表面。在未受干扰的土壤（对照）、蚯蚓在土壤中产生的洞穴衬里、蚯蚓粪便和从土壤中回收的生物炭颗粒中，测量了羧酸酯酶的活性——一种农药解毒酶。我们的结果表明：1）生物炭提高了土壤羧酸酯酶的活性，相对于无生物炭（对照）土壤，而在存在蚯蚓的情况下更为显著。2）在添加了塑料炭的土壤中发现了最大的酶活性。3）塑料炭的酶结合能力高于单独由动物粪便生产的生物炭，这与在土壤中发现的酶分布模式相符。4）土壤中蚯蚓的存在显著增加了塑料炭对酶促活化的潜力。这些发现表明，塑料炭适合于提高和稳定土壤酶活性，对蚯蚓没有毒性。
