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This document is a correction notice for an article titled "The roles of microorganisms in litter decomposition and soil formation" published in the journal Biogeochemistry. The correction addresses errors in Table 1 of the original article, specifically the "DI" values for various soil types and vegetation. The corrected values are provided for each entry. The correction notice also includes a statement from the publisher, Springer Nature, emphasizing their neutrality and lack of affiliation with any specific jurisdiction or institution. The authors of the original article are listed as Satoru Hobara, Takashi Osono, Dai Hirose, Kenta Noro, Mitsuru Hirota, and Ronald Benner. [Extracted from the article]

Selective removal of lignin and other recalcitrant compounds, collectively registered as acid-unhyrolyzable residue (AUR), results in bleaching of leaf litter, but the importance of bleaching in decomposition processes on forest soil has not been fully evaluated. The aims of this study were to elucidate the occurrence of bleached area in decomposing leaf litter and to compare chemical composition between bleached and nonbleached portions in a subtropical forest in Japan. Field incubation of leaf litter was performed over an 18-month period with the litterbag method. The decomposition processes during the first 9 month were characterized by the relatively rapid mass loss and increase of bleached area, whereas the mass loss was slowed down and the bleached area decreased thereafter. Mass loss of leaf tissues was faster and AUR content was lower in bleached than in nonbleached portions, indicating the acceleration of mass loss in bleached leaf tissues by the selective decomposition of recalcitrant compounds. The decrease in carbonyl-C in the bleached portions was associated with the increase of extractable nitrogen. The results suggest that the bleaching plays a dominant role in the transformation and turnover of organic compounds and nitrogen in decomposing leaf litter. [ABSTRACT FROM AUTHOR]

Effects of applying composted aquatic plants on soil chemistry, soil microbes (fungi and bacteria), and the growth of cultivated plant were demonstrated. To identify drivers promoting cultivated plant growth on soil amended with composted aquatic plant, empirical data of pot experiments were incorporated into structural equation models by hypothesizing causal relationships between the application of composted aquatic plants, soil chemistry, soil microbes, and cultivated plant growth. Cultivated plant growth, total carbon content, and bacterial and fungal richness in soil increased on soil applied with composted aquatic plants, and the composition of bacterial and fungal assemblages in soil were significantly different among the application treatments. Structural equation models explicitly demonstrated the relative importance of bacterial assemblages compared to soil chemistry as a promoter of cultivated plant growth in response to the application of composted aquatic plants. The present study is the first to demonstrate that the positive effects of composted aquatic plants on terrestrial plant growth are mediated by soil microbial processes. Our results could provide basic insights into the transfer and cycling of nutrients from aquatic to terrestrial systems through human activities. [ABSTRACT FROM AUTHOR]

The present study aimed to examine the effects of applying composted aquatic plants (CAP) on richness and composition of soil bacterial assemblages responsible for alkaline phosphatase production by pot experiments, as compared to the corresponding effects of inorganic chemical fertilizers (ICF). Soil bacterial assemblages were studied by metabarcoding the 16S region of ribosomal DNA as a universal genetic marker and the phoD alkaline phosphatase gene as a functional marker. The compositions of 16S and phoD assemblages were significantly different among soils applied with CAP, ICF, their mixture (MIX), and control (no application). Furthermore, the richness of phoD assemblages in soils was greater in CAP or MIX application than in ICF or control, although significant difference only existed between MIX and ICF. In conclusion, the present study illustrated that the application of composted aquatic plants affected the richness and composition of soil bacterial assemblages responsible for the production of alkaline phosphatase. [ABSTRACT FROM AUTHOR]

Little is known in continental Antarctic about patterns of abundance, diversity, and succession of microfungi within moss profiles consisting of live, senescent, and dead tissues in different stages of decomposition. In the present study, vertical patterns of the abundance and diversity of microfungi and their relationship with chemical compositions were examined within moss colonies collected from coastal outcrops in the Lützow-Holm Bay area (Queen Maud Land), East continental Antarctica. Total and darkly pigmented hyphal length, the richness of molecular operational taxonomic units (MOTUs) of microfungi, and the occurrence of Phoma herbarum and Pseudogymnoascus pannorum increased with the depth of moss profiles. The content of organic chemical components and nitrogen in moss tissues decreased, whereas ash content increased with the depth of moss profiles. Relative amount of recalcitrant compounds and total carbohydrates did not significantly differ among the vertical layers. The downward increase of the microfungal richness and occurrence in the Antarctic moss profiles without MOTU replacement was consistent with the directional-nonreplacement model of succession, indicative of the high environmental resistance, which represents the sum of the adverse factors hindering the success of species establishment. This contrasted with the fungal succession in arctic moss profiles, which accorded with the directional-replacement model, in which species replacement took place due to modification of habitat and competition. More hostile environmental conditions than those in the Arctic characterized the fungal succession and limited the fungal decomposition of moss in continental Antarctica. [ABSTRACT FROM AUTHOR]

Tundra and boreal forests in northern high latitudes contain significant amounts of carbon (C) in the soil, indicating the importance of clarifying controls on soil C dynamics in the region and their feedback effects on climate systems. In northern Alaska, variations in soil C processes are closely associated with variations in soil acidity within ecosystems; however, the reason for this association remains unclear. In this study, we demonstrate that it results from weathering and subsequent changes in soil geochemical characteristics, including minerals and adsorptive organic C. We sampled soils from 12 sites in Alaska along a 600-km transect from the Arctic Ocean to interior Alaska, spanning the biomes of tundra, tundra-boreal forest ecotone, and boreal forest. Mineral soil analyses revealed that soils with low pH have fewer base cations, more aluminum/iron minerals, and lower base saturation, indicating that weathering is a major function of these geochemical characteristics in the broad area over northern Alaska. Adsorbed organic C in soil presented strong correlations with Al and Fe minerals, soil pH, and soil total C and represented approximately 30-55% of total soil C, suggesting that soil C accumulation in the Alaskan ecosystems is strongly controlled by weathering-related changes in geochemical characteristics. An adsorption test supported these observations and illustrated a greater capacity for acidic soil to adsorb organic C. These findings demonstrate that variations in weathering-associated characteristics have a strong influence on the regional variation in C dynamics and biogeochemical consequences in the Alaskan ecosystems. [ABSTRACT FROM AUTHOR]

Much has been learned about the microbial decomposition of plant litter, but relatively little is known about microbial contributions to litter and soil chemistry. We conducted a 3-year litterbag experiment and measured hydrolyzable amino acids (AA) and amino sugars (AS) to gain insights about microbial contributions to the chemical characteristics of decomposing litter and soil. Microscopic observations of hyphae were used to estimate fungal contributions to litter. The carbon (C)-normalized yields of AA and AS increased during decomposition along with nitrogen (N), indicating a shift in chemical characteristics from C-rich plant-derived biopolymers to N-rich, microbially-derived biochemicals. The contributions of fungal biomass to C and N were minor, but necromass of fungi as melanized and clamp-bearing hyphae increased during litter decomposition. Yields of glucosamine and galactosamine in litter approached those in microorganisms, particularly bacteria, suggesting major contributions of bacterial residues to litter during decomposition. The microbial contributions to decomposing litter were consistent with those observed in organic and mineral soils. Microorganisms play important roles in the organization and stabilization of soil organic matter as well as N immobilization and organic C preservation. [ABSTRACT FROM AUTHOR]

Waterbirds are one of the most important groups of organisms inhabiting the land–water interface, especially with regard to mediating the transport of materials from the aquatic to the terrestrial environment. The great cormorant ( Phalacrocorax carbo) is a colonial piscivorous bird that transports nutrients from fresh water to forest. We measured cormorant-derived nitrogen at two nesting colonies on the Isaki Peninsula and Chikubu Island at Lake Biwa, Japan, and analyzed the long-term effects of cormorant colonization on the forest nitrogen cycle, and the mechanisms of nitrogen retention. Three sites were examined in each colony: a currently occupied area, a previously occupied but now abandoned area, and a control area never colonized by cormorants. High nitrogen stable isotope ratios of cormorant excreta, the forest floor, mineral soil, and living plants showed cormorant-derived nitrogen in both occupied and abandoned areas. The relationship between δ15N and N content showed that the high δ15N of the excreta and N turnover in the soil were important at the occupied sites, whereas high δ15N of litter was important at the abandoned sites. Physiological changes of various organisms are also important for the N decomposition process. In conclusion, cormorant-derived nitrogen remains in the forest ecosystem as a result of two cormorant activities: heavy deposition of excreta and collection of nitrogen-rich nest material. Colony stage (occupied, abandoned, or never inhabited) and historical change of N decomposition process of an area can be identified from the relationship between δ15N and N content. [ABSTRACT FROM AUTHOR]

Although much concern has been directed at nitrogen (N) cycling in terrestrial ecosystems with bird colonies, little has been clarified on the processes of phosphorus (P) cycling itself, and few comparisons between P and N cycling in bird colonies have been made. On the Isaki Headland and Chikubu Island, which are located on or near the shore of Lake Biwa, Central Japan, a dramatic increase in the population of cormorants has occurred since the 1980s. There has been a concomitant increase in the transport of nutrients from the lake to the waterside ecosystems. We compared the pools and dynamics of N and P in the cormorant-colony forests in order to clarify the effects of differences in soil N and P dynamics on the N-P balance of these colony forests. The total N concentration in the forest floor at excrement-influenced sites was not significantly different from that at sites without such influence, in spite of the heavy load of cormorant-derived N. In contrast to N, forest floor P concentration at the sites with excrement influence was significantly higher compared to sites without such influence, resulting in the lower forest floor N/P ratio at the excrement-influenced sites even after colony abandonment. The site pattern of total N and P concentrations and N/P ratio for mineral soil was similar to that for the forest floor. It seems that the leaky character for N and the accumulative character for P are due to the high mobility of nitrate in soils and the tight absorption of inorganic P to clay minerals, respectively. The site pattern of N/P ratios observed forChamaecyparis obtusaSieb. et Zucc. leaves is consistent with that for the forest floor and/or mineral soil, suggesting that the soil geochemical property was reflected in the foliar N/P ratio. The chemistry of throughfall and soil solution was also changed due to deposition of cormorant excrement, and the changes continued for a few years after abandonment of the colony. The quantitative analyses for N and P suggested that the major part of N and P transported by cormorants was not retained in plant matter and the surface soil beneath the colony but instead leached into deeper soil layers. The influence of cormorant excrement on nutrient balance of the whole colony ecosystem is also discussed. [ABSTRACT FROM AUTHOR]

To evaluate the effects of avian-derived N deposition on forest C and N status, we investigated quantity and quality of litterfall, and chemical quality and N transformations in the forest floor from five sites that had been exposed to waterbird breeding colonies to differing degrees. The highest litterfall input of 2.6 t ha-1 month-1 was observed in the forest stand (Site 2) where intense bird breeding activity had been observed. Litterfall C/N was highest at the control site (no breeding activity) and decreased as the colonization stages advanced. Nitrogen concentration in litterfall and the forest floor was higher at those sites (Sites 3 and 4) where bird breeding had ceased and which represented the 'post-colony' situation, and consequently C/N and lignin/N of forest floor decreased. NH4-N pool size in the forest floor was higher at Site 2, probably due to ongoing input and mineralization of bird excreta. Nitrification rate and percent nitrification were highest at Sites 3 and 4. From these results we conclude that study sites exposed to bird colonies show signs of N excess even after colonies are abandoned. [ABSTRACT FROM AUTHOR]