scholarly journals Microplastic effects on carbon cycling processes in soils

PLoS Biology ◽  
2021 ◽  
Vol 19 (3) ◽  
pp. e3001130 ◽  
Author(s):  
Matthias C. Rillig ◽  
Eva Leifheit ◽  
Johannes Lehmann
Keyword(s):  
Global Change ◽  
Plant Growth ◽  
Carbon Cycle ◽  
Carbon Cycling ◽  
Litter Decomposition ◽  
Terrestrial Ecosystems ◽  
Biogeochemical Cycles ◽  
Research Needs ◽  
Concerted Effort ◽  
Soil Microbial

Microplastics (MPs), plastic particles <5 mm, are found in environments, including terrestrial ecosystems, planetwide. Most research so far has focused on ecotoxicology, examining effects on performance of soil biota in controlled settings. As research pivots to a more ecosystem and global change perspective, questions about soil-borne biogeochemical cycles become important. MPs can affect the carbon cycle in numerous ways, for example, by being carbon themselves and by influencing soil microbial processes, plant growth, or litter decomposition. Great uncertainty surrounds nano-sized plastic particles, an expected by-product of further fragmentation of MPs. A major concerted effort is required to understand the pervasive effects of MPs on the functioning of soils and terrestrial ecosystems; importantly, such research needs to capture the immense diversity of these particles in terms of chemistry, aging, size, and shape.

scholarly journals Soil microbial diversity and litter decomposition increase along a forest recovery gradient in tropical montane forests of Malaysian Borneo

2020 ◽  
Author(s):  
Renee Sniegocki ◽  
Jessica B. Moon ◽  
Abigail L. Rutrough ◽  
Jude Gireneus ◽  
Jaya Seelan S. Seelan ◽  
...  
Keyword(s):  
Microbial Diversity ◽  
Carbon Cycling ◽  
Litter Decomposition ◽  
Forest Recovery ◽  
Forest Conversion ◽  
Soil Microbial Diversity ◽  
Montane Forests ◽  
Soil Microbial ◽  
Tropical Montane Forests ◽  
Malaysian Borneo

AbstractLogging and forest conversion are occurring at alarming rates in the tropical forests. These disturbances alter soil chemistry and microbial diversity, and disrupt carbon cycling through shifts in litter decomposition. Direct links between microbial diversity and soil properties such as pH are well established; however, the indirect impacts of logging and forest conversion on microbial diversity and litter decomposition are poorly understood. We investigated how soil properties and soil functions change across a forest recovery gradient in the tropical montane forests of Malaysian Borneo. We used surface (top 5 cm) soil to assess soil physicochemical properties, next-generation DNA sequencing to assess soil microbial diversity, and standardized litterbags to assess litter decomposition and stabilization. Our results show that soils of the older forests harbored significantly greater microbial diversity, decomposed litter faster, and stabilized greater amounts of litter than soils of the younger forests and converted sites. These results suggest that logging and forest conversion significantly affect soil microbial diversity and can have lasting effects on carbon cycling in tropical montane forests.

scholarly journals Biotic interactions mediate soil microbial feedbacks to climate change

2015 ◽  
Vol 112 (22) ◽  
pp. 7033-7038 ◽  
Author(s):  
Thomas W. Crowther ◽  
Stephen M. Thomas ◽  
Daniel S. Maynard ◽  
Petr Baldrian ◽  
Kristofer Covey ◽  
...  
Keyword(s):  
Global Change ◽  
Carbon Cycle ◽  
Microbial Activity ◽  
Climate Feedback ◽  
Climate Feedbacks ◽  
Top Down ◽  
Soil Animals ◽  
Bottom Up ◽  
Soil Microbial ◽  
Change Factors

Decomposition of organic material by soil microbes generates an annual global release of 50–75 Pg carbon to the atmosphere, ∼7.5–9 times that of anthropogenic emissions worldwide. This process is sensitive to global change factors, which can drive carbon cycle–climate feedbacks with the potential to enhance atmospheric warming. Although the effects of interacting global change factors on soil microbial activity have been a widespread ecological focus, the regulatory effects of interspecific interactions are rarely considered in climate feedback studies. We explore the potential of soil animals to mediate microbial responses to warming and nitrogen enrichment within a long-term, field-based global change study. The combination of global change factors alleviated the bottom-up limitations on fungal growth, stimulating enzyme production and decomposition rates in the absence of soil animals. However, increased fungal biomass also stimulated consumption rates by soil invertebrates, restoring microbial process rates to levels observed under ambient conditions. Our results support the contemporary theory that top-down control in soil food webs is apparent only in the absence of bottom-up limitation. As such, when global change factors alleviate the bottom-up limitations on microbial activity, top-down control becomes an increasingly important regulatory force with the capacity to dampen the strength of positive carbon cycle–climate feedbacks.

scholarly journals Tire abrasion particles negatively affect plant growth even at low concentrations and alter soil biogeochemical cycling

2021 ◽  
Author(s):  
Eva F Leifheit ◽  
Hanna L Kissener ◽  
Erik Faltin ◽  
Masahiro Ryo ◽  
Matthias C Rillig
Keyword(s):  
Plant Growth ◽  
Soil Respiration ◽  
Litter Decomposition ◽  
Soil Ph ◽  
Terrestrial Ecosystems ◽  
Plant Performance ◽  
Soil Parameters ◽  
Potential Hazard ◽  
Terrestrial Environment ◽  
Low Concentrations

Tire particles (TPs) are a major source of microplastic on land, and considering their chemical composition, they represent a potential hazard for the terrestrial environment. We studied the effects of TPs at environmentally relevant concentrations along a wide concentration gradient (0 - 160 mg g-1) and tested the effects on plant growth, soil pH and the key ecosystem process of litter decomposition and soil respiration. The addition of TPs negatively affected shoot and root growth already at low concentrations. Tea litter decomposition slightly increased with lower additions of TPs but decreased later on. Soil pH increased until a TP concentration of 80 mg kg-1 and leveled off afterwards. Soil respiration clearly increased with increasing concentration of added TPs. Plant growth was likely reduced with starting contamination and stopped when contamination reached a certain level in the soil. The presence of TPs altered a number of biogeochemical soil parameters that can have further effects on plant performance. Considering the quantities of yearly produced TPs, their persistence, and toxic potential, we assume that these particles will eventually have a significant impact on terrestrial ecosystems.

scholarly journals Tire abrasion particles negatively affect plant growth even at low concentrations and alter soil biogeochemical cycling

2021 ◽  
Author(s):  
Eva F. Leifheit ◽  
Hanna L. Kissener ◽  
Erik Faltin ◽  
Masahiro Ryo ◽  
Matthias C. Rillig
Keyword(s):  
Plant Growth ◽  
Soil Respiration ◽  
Litter Decomposition ◽  
Soil Ph ◽  
Terrestrial Ecosystems ◽  
Plant Performance ◽  
Soil Parameters ◽  
Potential Hazard ◽  
Terrestrial Environment ◽  
Low Concentrations

AbstractTire particles (TPs) are a major source of microplastic on land, and considering their chemical composition, they represent a potential hazard for the terrestrial environment. We studied the effects of TPs at environmentally relevant concentrations along a wide concentration gradient (0–160 mg g−1) and tested the effects on plant growth, soil pH and the key ecosystem process of litter decomposition and soil respiration. The addition of TPs negatively affected shoot and root growth already at low concentrations. Tea litter decomposition slightly increased with lower additions of TPs but decreased later on. Soil pH increased until a TP concentration of 80 mg g−1 and leveled off afterwards. Soil respiration clearly increased with increasing concentration of added TPs. Plant growth was likely reduced with starting contamination and stopped when contamination reached a certain level in the soil. The presence of TPs altered a number of biogeochemical soil parameters that can have further effects on plant performance. Considering the quantities of yearly produced TPs, their persistence, and toxic potential, we assume that these particles will eventually have a significant impact on terrestrial ecosystems.

Can repeated soil amendment with biogas digestates increase soil suppressiveness toward non-specific soil-borne pathogens in agricultural lands?

2020 ◽  
pp. 1-12
Author(s):  
L. M. Manici ◽  
F. Caputo ◽  
G. A. Cappelli ◽  
E. Ceotto
Keyword(s):  
Plant Growth ◽  
Biomass Production ◽  
Soil Amendment ◽  
Plant Biomass ◽  
Amended Soils ◽  
Soil Suppressiveness ◽  
Soil Microbial ◽  
Soil Borne Pathogens ◽  
The Impact ◽  
Plant Biomass Production

Abstract Soil suppressiveness which is the natural ability of soil to support optimal plant growth and health is the resultant of multiple soil microbial components; which implies many difficulties when estimating this soil condition. Microbial benefits for plant health from repeated digestate applications were assessed in three experimental sites surrounding anaerobic biogas plants in an intensively cultivated area of northern Italy. A 2-yr trial was performed in 2017 and 2018 by performing an in-pot plant growth assay, using soil samples taken from two fields for each experimental site, of which one had been repeatedly amended with anaerobic biogas digestate and the other had not. These fields were similar in management and crop sequences (maize was the recurrent crop) for the last 10 yr. Plant growth response in the bioassay was expressed as plant biomass production, root colonization frequency by soil-borne fungi were estimated to evaluate the impact of soil-borne pathogens on plant growth, abundance of Pseudomonas and actinomycetes populations in rhizosphere were estimated as beneficial soil microbial indicators. Repeated soil amendment with digestate increased significantly soil capacity to support plant biomass production as compared to unamended control in both the years. Findings supported evidence that this increase was principally attributable to a higher natural ability of digestate-amended soils to reduce root infection by saprophytic soil-borne pathogens whose inoculum was increased by the recurrent maize cultivation. Pseudomonas and actinomycetes were always more abundant in digestate-amended soils suggesting that both these large bacterial groups were involved in the increase of their natural capacity to control soil-borne pathogens (soil suppressiveness).

scholarly journals Historical climate controls soil respiration responses to current soil moisture

2017 ◽  
Vol 114 (24) ◽  
pp. 6322-6327 ◽  
Author(s):  
Christine V. Hawkes ◽  
Bonnie G. Waring ◽  
Jennifer D. Rocca ◽  
Stephanie N. Kivlin
Keyword(s):  
Climate Change ◽  
Soil Moisture ◽  
Soil Respiration ◽  
Carbon Cycling ◽  
Large Scale ◽  
Microbial Respiration ◽  
Rainfall Gradient ◽  
Soil Microbial ◽  
Historical Climate ◽  
Moisture Dependence

Ecosystem carbon losses from soil microbial respiration are a key component of global carbon cycling, resulting in the transfer of 40–70 Pg carbon from soil to the atmosphere each year. Because these microbial processes can feed back to climate change, understanding respiration responses to environmental factors is necessary for improved projections. We focus on respiration responses to soil moisture, which remain unresolved in ecosystem models. A common assumption of large-scale models is that soil microorganisms respond to moisture in the same way, regardless of location or climate. Here, we show that soil respiration is constrained by historical climate. We find that historical rainfall controls both the moisture dependence and sensitivity of respiration. Moisture sensitivity, defined as the slope of respiration vs. moisture, increased fourfold across a 480-mm rainfall gradient, resulting in twofold greater carbon loss on average in historically wetter soils compared with historically drier soils. The respiration–moisture relationship was resistant to environmental change in field common gardens and field rainfall manipulations, supporting a persistent effect of historical climate on microbial respiration. Based on these results, predicting future carbon cycling with climate change will require an understanding of the spatial variation and temporal lags in microbial responses created by historical rainfall.

Sign in / Sign up

Export Citation Format

Share Document