Responses of soil microbial and nematode communities to aluminum toxicity in vegetated oil-shale-waste lands

Abstract

Both soil nematodes and microorganisms have been shown to be sensitive bioindicators of soil recovery in metal-contaminated habitats; however, the underlying processes are poorly understood. We investigated the relationship among soil microbial community composition, nematode community structure and soil aluminum (Al) content in different vegetated aluminum-rich ecosystems. Our results demonstrated that there were greater soil bacterial, fungal and arbuscular mycorrhizal fungal biomass in Syzygium cumini plantation, greater abundance of soil nematodes in Acacia auriculiformis plantation, and greater abundance of soil predatory and herbivorous nematodes in Schima wallichii plantation. The concentration of watersoluble Al was normally greater in vegetated than nonvegetated soil. The residual Al and total Al concentrations showed a significant decrease after planting S. cumini plantation onto the shale dump. Acid extractable, reducible and oxidisable Al concentrations were greater in S. wallichii plantation. Stepwise linear regression analysis suggests the concentrations of water-soluble Al and total Al content explain the most variance associated with nematode assembly; whereas, the abundance of early-successional nematode taxa was explained mostly by soil moisture, soil organic C and total N rather than the concentrations of different forms of Al. In contrast, no significant main effects of either Al or soil physico-chemical characteristics on soil microbial biomass were observed. Our study suggests that vegetation was the primary driver on soil nematodes and microorganisms and it also could regulate the sensitivity of bio-indicator role mainly through the alteration of soil Al and physico-chemical characteristics, and S. cumini is effective for amending the Al contaminated soils.

Evidence that acidification‐induced declines in plant diversity and productivity are mediated by changes in below‐ground communities and soil properties in a semi‐arid steppe

“…Hence, the decrease might be explained by a direct detrimental effect of H + ions on omnivorous + carnivorous nematodes (Hyv€ onen & Persson 1990;Kuperman & Edwards 1997). The abundance of soil nematodes is less affected by Al 3+ concentration than by H + concentration (Nagy 1999;Shao et al 2012), although the abundance of omnivorous + carnivorous nematodes was also associated with Al 3+ concentrations in present study.…”

Nutrient-induced acidification modulates soil biodiversity-function relationships

“…N-induced soil acidification has likely increased the concentration of ions in soil pore water, which in turn may constrain the ability of nematodes to adjust water state 59 , 61 . In particular, increases of both Al 3+ and H + concentration have been proposed to have direct detrimental effects on soil nematode, particularly for those at high trophic levels, such as omnivorous and predaceous nematodes 62 , 63 . Nutrient enrichment can also indirectly affect the diversity and the relative composition of different nematode guilds through cascading up its effects on plants 61 , 64 , and bacteria and fungi 65 (Fig.…”

Διερεύνηση Της Ρύπανσης Με Βαρέα Μέταλλα Και Ραδιενέργεια, Της Λεκάνης Κοζάνης - Πτολεμαΐδας Με Τη Χρήση Βιολογικών Δεικτών, Νερού Και Μικροοργανισμών

“…Οι προκαρυώτες είναι παρόντες σε όλα τα περιβαλλοντικά επίπεδα και διαδραµατίζουν βασικό ρόλο στους κύκλους των στοιχείων όπως π.χ. του αζώτου, του άνθρακα, του θείου, και του φωσφόρου (Shao et al, 2012 Rhodococcus, Microbacterium, Desulfovibrio, Enterobacter, Escherichia, Shewanella, Vibrio, Providencia, Alcaligenes and Bacillus (Camargo et al, 2003;Fulladosa et al, 2006;Pattanapipitpaisal et al, 2001;Thacker et al, 2006). Η αναγωγή του Cr(VI)…”