Microbial community structure and nutrient dynamics in forest soils colonized by bracken fern (Pteridium aquilinum)

Soil Microorganisms ◽

Nutrient Dynamics ◽

Pteridium Aquilinum ◽

Bracken Fern ◽

Soil Microbial

Bracken fern (Pteridium aquilinum) is one of the most successful plant colonizers of soils in temperate regions; however, its effects on microbial community structure and activity and nutrient dynamics remain poorly understood. We studied whether colonization of forest soil by bracken fern modifies the structure and function of the soil microbial communities and considered the implications for ecosystem functioning. For this purpose, we analyzed microbial community structure (PLFAs) and activity (basal respiration, metabolic quotient), litter decomposition and nutrient dynamics (C, N and P) in monospecific oak (Quercus robur L.), eucalyptus (Eucalyptus globulus Labill.) and maritime pine forests (Pinus pinaster Aiton) colonized by bracken fern. Colonization of forest soil by bracken fern led to a reduction in differences in microbial community structure, as revealed by principal component and cluster analysis, although samples from oak forests were grouped separately. According to this, bracken litter decomposed to a greater extent than native tree litter in pine forest soils, whereas the opposite was found in oak forest soils. Such differences were not observed in eucalyptus forest soils. Colonization by bracken fern affected C mineralization, with no difference between the different types of forest; however, both N and P mineralization were higher in oak than in the other types of forest. In conclusion, colonization by bracken fern homogenizes soil microbial community structure. Differences in the decomposability of bracken litter in the different forest systems suggest a high degree of metabolic specialization of soil microorganisms. Thus, the soil microorganisms associated with bracken are continuously driven to decompose the bracken litter. In the long-term this will alter nutrient cycling, slowing decomposition and enhancing sequestering of nutrients by bracken ferns.

Soil Microbial Community Structure and Target Organisms under Different Fumigation Treatments

Applied and Environmental Soil Science ◽

10.1155/2015/673264 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 9

Author(s):

Sadikshya R. Dangi ◽

James S. Gerik ◽

Rebecca Tirado-Corbalá ◽

Husein Ajwa

Keyword(s):

Community Structure ◽

Microbial Community ◽

Methyl Bromide ◽

Soil Microorganisms ◽

Phospholipid Fatty Acid ◽

Natural Soil ◽

Soil Microbial ◽

Field Samples

Producers of several high-value crops in California rely heavily on soil fumigants to control key diseases, nematodes, and weeds. Fumigants with broad biocidal activity can affect both target and nontarget soil microorganisms. The ability of nontarget soil microorganisms to recover after fumigation treatment is critical because they play an important role in sustaining the health of agricultural and natural soil systems. Fumigation trial was conducted in Parlier, CA, and the study focuses on the effects of different rates of Telone C35 and also methyl bromide fumigation with polyethylene (PE) and totally impermeable film (TIF) tarps on target and nontarget soil microorganisms using field samples. Results indicated that the populations of target organisms, such asFusarium oxysporumandPythiumspp., were reduced at all rates of fumigants. Phospholipid fatty acid (PLFA) analysis indicated that all major nontarget soil microbial groups such as Gram positive bacteria, Gram negative bacteria, fungi, and arbuscular mycorrhizal fungi (AMF) were affected by methyl bromide (MeBr) fumigation treatment. In general, the effects of Telone C35 (299 L/ha) under PE tarp had the least impact on microbial community structure and better effect on controlling target microorganisms and, therefore, indicated the better option among fumigation treatments.

Root controls on soil microbial community structure in forest soils

Oecologia ◽

10.1007/s00442-006-0402-7 ◽

2006 ◽

Vol 148 (4) ◽

pp. 650-659 ◽

Cited By ~ 124

Author(s):

Justin B. Brant ◽

David D. Myrold ◽

Elizabeth W. Sulzman

Keyword(s):

Community Structure ◽

Microbial Community ◽

Forest Soils ◽

Soil Microbial Community ◽

Soil Microbial

Effects of microplastic and microglass particles on soil microbial community structure in an arable soil (Chernozem)

10.5194/soil-2019-38 ◽

2019 ◽

Cited By ~ 1

Author(s):

Katja Wiedner ◽

Steven Polifka

Keyword(s):

Community Structure ◽

Microbial Community ◽

Soil Microbial Community ◽

Soil Microorganisms ◽

Soil Microbiology ◽

Treated Soil ◽

Soil Microbial ◽

Terrestrial Environments

Abstract. Since decades, microplastics and microglass enter aquatic and terrestrial environments. The complexity of the environmental impact is difficult to capture and consequences on ecosystem components e.g. such as soil microorganisms are virtually unknown. Addressing this issue, we performed an incubation experiment by adding 1 % of five different types of impurities (≤ 100 µm) to an agricultural used soil (Chernozem). Four microplastic types (polypropylene (PP), low density polyethylene (LD-PE), polystyrene (PS) and polyamide12 (PA12)) and microglass were used as treatment variants. After 80 days of incubation at 20 °C, we examined soil microbial community structure by using phospholipid fatty acids (PLFA) as markers for bacteria, fungi and protozoa. The results showed that soil microorganisms were not significantly affected by the presence of microplastic and microglass. However, PLFAs tend to increase in LD-PE (27 %), PP (18 %) and microglass (11 %) treated soil in comparison with untreated soil, whereas PLFAs in PA12 (32 %) and PS (11 %) treated soil decreased. Interestingly, the comparison of PLFA contents between microplastic types revealed significant differences of PA12 (−87 %) and PS (−42 %) compared to LD-PE. Furthermore, bacterial PLFAs showed a much higher variability after microplastic incubation whereby fungi seem to be more unaffected after 80 days of incubation. Same for protozoa, which were more or less unaffected by microplastic treatment showing only minor reduction of the PLFA contents compared to control. In contrast, microglass has obviously an inhibiting effect on protozoa because PLFAs were under the limit of determination. Our study provides hints, that microplastics have, depending on type, contrary effects on soil microbiology and microglass seems to be highly toxic for protozoa.

Effects of microplastic and microglass particles on soil microbial community structure in an arable soil (Chernozem)

SOIL ◽

10.5194/soil-6-315-2020 ◽

2020 ◽

Vol 6 (2) ◽

pp. 315-324

Author(s):

Katja Wiedner ◽

Steven Polifka

Keyword(s):

Community Structure ◽

Microbial Community ◽

Soil Microbial Community ◽

Soil Microorganisms ◽

Soil Microbiology ◽

Worst Case ◽

Treated Soil ◽

Soil Microbial

Abstract. Microplastic and microglass particles from different sources enter aquatic and terrestrial environments. The complexity of their environmental impact is difficult to capture, and the consequences for ecosystem components, for example, the soil microorganisms, are virtually unknown. To address this issue, we performed an incubation experiment by adding 1 % of five different types of impurities (≤100 µm) to an agriculturally used soil (Chernozem) and simulating a worst-case scenario of contamination. The impurities were made of polypropylene (PP), low-density polyethylene (LDPE), polystyrene (PS), polyamide 12 (PA12) and microglass. After 80 d of incubation at 20 ∘C, we examined the soil microbial community structure by using phospholipid fatty acids (PLFAs) as markers for bacteria, fungi and protozoa. The results showed that soil microorganisms were not significantly affected by the presence of microplastic and microglass. However, PLFAs tend to increase with LDPE (28 %), PP (19 %) and microglass (11 %) in treated soil in comparison with untreated soil, whereas PLFAs in PA12 (32 %) and PS (11 %) in treated soil decreased. Interestingly, PLFAs revealed significant differences in PA12 (−89 %) and PS (−43 %) in comparison with LDPE. Furthermore, variability of bacterial PLFAs was much higher after microplastic incubation, while fungi seemed to be unaffected from different impurities after 80 d of incubation. Similar results were shown for protozoa, which were also more or less unaffected by microplastic treatment as indicated by the minor reduction in PLFA contents compared to the control group. In contrast, microglass seems to have an inhibiting effect on protozoa because PLFAs were under the limit of determination. Our study indicated that high amounts of different microplastics may have contrary effects on soil microbiology. Microglass might have a toxic effect for protozoa.