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Biodegradable plastics applied to soil stimulate the production of greenhouse gases and inhibit plant growth under aerobic conditions. This study aimed to examine the effects of biodegradable plastics on paddy rice growth and greenhouse gas emission under flooding conditions in pot experiments and also on greenhouse gas production under flooding conditions in an incubation experiment. Two series of pot experiments were conducted with rice (Oryza sativa). First series as immediate flooded and 2nd series as 2 weeks nonflooding before flooded, and both kept flooded until harvest. The following four kinds of materials were added to the sandy paddy soil, (1) nonwoven fabric sheets made of polylactic acid and polybutylene-succinate, (2) laminate sheets made of polybutylene adipate terephthalate and pulp, (3) cellulose filter paper, and (4) rice straw. Only soil was used as control. Methane (CH4) emission, measured by chamber method followed by gas chromatography, was significantly larger only in the cellulose treatment than the laminate treatment in the immediate flooded series, indicating that biodegradable plastics had no significant impact on CH4 emission from paddy rice soil. Rice growth and yield did not show significant difference among treatments in both series. Incubation experiment showed the largest CH4 production in cellulose-amended soil, followed by straw-amended and laminate amended soils, and least in fabric-amended soil, while CO2 did not show significant differences among treatments. We need further examination with different biodegradable plastics for a longer period that test used in this study. [ABSTRACT FROM AUTHOR]

Civilian and military activities are sources of water and soil contamination by inorganic and organic contaminants caused by shooting practices, warfare, and/or mechanized military training. Lead poisoning and contaminant bioaccumulation due to spent shots or other related military contaminants have been widely studied for mammals, birds, and plants. Although there are different papers on the impact on earthworms, information on micro and mesofauna (i.e., collembola, nematodes, etc.) is still scarce. Here, we review the published data regarding the impact of civilian and military shooting activities, including war-impacted areas, focusing on soil organisms, from microbial communities to the ecotoxicological effects on terrestrial organisms. One hundred eleven studies were considered where earthworms and enchytraeids were widely studied, especially under ecotoxicological assays with Pb and energetic-related compounds from military explosives. There is a lack of information on soil organism groups, such as mites, ants, or gastropods, which play important roles in soil function. Data from combined exposures (e.g., PTEs + TNT and PTEs + PAHs) is scarce since several studies focused on a single contaminant, usually Pb, when combined contaminants would be more realistic. Ecotoxicological assays should also cover other understudied ammunition elements, such as Bi, Cu, or W. [ABSTRACT FROM AUTHOR]

Essential soil functions such as plant productivity, C storage, nutrient cycling and the storage and purification of water all depend on soil biological processes. Given this insight, it is remarkable that in modeling of these soil functions, the various biological actors usually do not play an explicit role. In this review and perspective paper we analyze the state of the art in modeling these soil functions and how biological processes could more adequately be accounted for. We do this for six different biologically driven processes clusters that are key for understanding soil functions, namely i) turnover of soil organic matter, ii) N cycling, iii) P dynamics, iv) biodegradation of contaminants v) plant disease control and vi) soil structure formation. A major conclusion is that the development of models to predict changes in soil functions at the scale of soil profiles (i.e. pedons) should be better rooted in the underlying biological processes that are known to a large extent. This is prerequisite to arrive at the predictive models that we urgently need under current conditions of Global Change. [ABSTRACT FROM AUTHOR]

This document is an editorial from the journal "Biology & Fertility of Soils" discussing recent advances in the study of biology and fertility in paddy field soil. Paddy fields are flooded during rice cultivation, which affects the activities of microorganisms and microbial community structures. The editorial highlights the importance of understanding the biology and fertility of paddy field soil for sustainable rice production. The special issue of the journal includes research papers on topics such as nutrient cycles, decomposition of organic matter, greenhouse gas production, and interactions between microbes and rice plants. The authors express gratitude to the contributors and hope that the contents of the special issue provide new insights into this field of study. [Extracted from the article]

This article discusses the role of soil microorganisms in the dynamics of soil organic matter (SOM) and how it is affected by land use and climate change. The authors highlight recent research that has shifted the understanding of SOM dynamics, emphasizing the importance of microbially derived SOM, microbial necromass, and root biomass and exudates. The article also presents five papers that investigate microbial control of SOM dynamics under different land uses and management practices. The findings suggest that microbial carbon use efficiency (CUE) is a key factor in balancing SOC accumulation and loss. The article concludes by emphasizing the need for a deeper understanding of microbial control of SOM dynamics in order to develop effective strategies for climate change adaptation and mitigation. [Extracted from the article]