Soil invertebrate and microbial communities, and decomposition as indicators of polycyclic aromatic hydrocarbon contamination

Abstract

Soil organisms are useful for quantification of ecological impact of chemical contamination of soils. This study examined the effects of creosote (complex mixture of polycyclic aromatic hydrocarbons) on composition and abundance of soil invertebrates (nematodes, collembolans and mites) and decomposition processes. Thirty intact soil cores and adjacent litter samples were collected each of three times during the 1998 growing season from soil contaminated with creosote for 50 years. Each core was divided evenly into two subsamples. Abundance of nematodes (by family), Collembola (by family), mites (by Oribatida and others), total bacterial biomass, and active fungal biomass were quantified in the first subsample; soil properties including polycyclic aromatic hydrocarbon (PAH) concentration, organic carbon, pH, electrical conductivity (EC), bulk density, soil moisture and soil texture were measured in the second subsample. Creosote affected soil food webs and decomposition more by altering habitat of microinvertebrates and their prey, fungi and bacteria, than by direct toxicity. We hypothesize that nematodes were affected directly by PAH, more than collembolans or mites, because of their intimate contact with contaminated soil particles and permeable cuticles. Collembola and mites explained decomposition of 100% cellulose and mixed cellulose/lignin substrates better than nematodes because of their co-location in the litter layer. This is the first study to examine effects of PAH contamination on soil food webs and ecological processes.

Importance of soil physical characteristics for petroleum hydrocarbons phytoremediation: A review

“…However, the petroleum compounds may also interact with some other ambient abiotic factors (including soil bulk density, nutrient, moisture and oxygen concentration, temperature, EC, and pH of the soil) when determining organic matter decomposition (Blakely et al, 2002). According to Galitskaya et al (2014), in testing several techniques, adding compost to the petroleum contaminated soil, significantly promote bioremediation in most cases.…”

Nematoides: bioindicadores de sustentabilidade e mudanças edafoclimáticas

“…A umidade do solo, a umidade relativa e os fatores ambientais afetam diretamente a sobrevivência dos nematoides. Os nematoides possuem variadas formas de adaptação a mudanças que ocorrem no ambiente causadas por diversos fatores, entre os quais o manejo dos cultivos, estresse climático, época de plantio, fisiologia das plantas e melhoramento genético (BLAKELY et al 2002).…”

Residues and source identification of persistent organic pollutants in farmland soils irrigated by effluents from biological treatment plants

“…There were plenty of research work focused on heavy metal accumulation and transfer between soil and water in farmlands that using wastewater or effluents from SPT for irrigation (Karvelas et al, 2003;Zheng et al, 2001;Zhu, 2001). Less has been known on persistent organic contaminants, which could also be accumulated in soils and transferred through food chains and consequently cause adverse health effects on human or biological effects on soil fauna and flora after long-term application (Blakely et al, 2002;Tang et al, 2002;Wang et al, 2003a,b;Migaszewski et al, 2002). In the past, few studies have been done on the potential accumulation of persistent organic contaminants in soils after long-term application of the effluents from SWTP.…”