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Fine root traits span two independent axes of variation, the conservation and collaboration axes, which define the root economic space (RES). However, whether early‐stage fine root decomposition rates (quantified as proportion mass loss, i.e. pml) are more strongly related to collaboration or conservation traits remains unclear. We studied 63 tree species in New Zealand's temperate rain forest. We determined the phylogenetic signal in pml and fine root traits, conducted phylogenetic principal component analysis and used phylogenetic generalized least squares to determine which traits are most strongly related to pml. Root decomposition exhibited a high phylogenetic signal and was more strongly related to the conservation than the collaboration axis. Root tissue density (RTD) was negatively correlated and root nitrogen (RN) was positively correlated with pml. Root diameter was positively yet weakly correlated with pml, but specific root length was uncorrelated with pml. The lignin‐to‐N ratio and root cellulose were the strongest predictors of pml. Synthesis: Early‐stage fine root decomposition is most strongly driven by tissue quality traits, such as root nitrogen, tissue density and lignin‐to‐N ratio, which all align with the conservation axis of the root economics space. However, root diameter plays a weak yet undeniable role in early‐stage fine root decomposition. Some thick‐rooted species decomposed faster, possibly due to the higher quality cortical tissue. Thin‐rooted species decomposed slower, possibly because of their higher cellulose concentration that maintains the structural integrity of small diameter roots. Relationships between decomposition and other traits that align with the collaboration gradient deserve further study across the phylogeny of vascular plants. [ABSTRACT FROM AUTHOR]

We investigated how microbial decomposition in headwater streams is influenced by environmental factors and litter quality, including the potential adaptation of microbes to decompose more efficiently leaf‐litter species from their native range (HFA, ‘home‐field advantage’ hypothesis). We conducted a leaf‐litter decomposition experiment in streams from four subregions contrasting in water chemistry and temperature regime, using cross‐subregion reciprocal incubations of the dominant riparian plant species in each subregion. Low‐quality litters decomposed faster at their native site, supporting the HFA hypothesis for low‐quality litter species. Moreover, temperature sensitivity of decomposition of low‐, but not high‐, quality litters was close to that predicted by the metabolic theory of ecology. Among litter traits, nitrogen content and toughness were the major predictors of decomposition. Temperature and nitrate concentration in stream water enhanced decomposition but, these two extrinsic factors did not act synergistically. Together our results indicated that leaf‐litter traits have a leading role as drivers of the decomposition process in headwater streams. However, this role is indirect, and occurs because low‐quality litters modulate the decomposition effects of environmental drivers (temperature and N in water). Consistently with the above finding, HFA occurred only in low‐quality litter. Thus, if climate change leads to minor local changes in litter quality, microbial decomposition would be accelerated additively by warming and stream‐water nitrate enrichment, with more pronounced effects on low‐quality litters. [ABSTRACT FROM AUTHOR]

Termites—one of the most abundant animal groups in tropical ecosystems—are vital in nutrient recycling, contributing significantly to maintaining ecosystem functioning. However, how selective they are in their litter food choice, and whether they prefer nutritious or less nutritious litter substrates, are still important unresolved questions.Here, we test the effect of litter traits on the removal of litter by fungus‐growing termites, a dominant group of macrodetritivores in the Serengeti‐Mara ecosystem. We used metal‐mesh litterbags to measure the mass loss of stem and leaf litter from 23 grass species after an incubation period of 61 days.Sheeting—soil deposits indicating termite presence—strongly increased with tannin and phenolic compounds, especially in leaf litter (R2 = 0.54), where highly aromatic species like Cymbopogon caesius and Bothriochloa insculpta exhibited the highest sheeting rates. Litterbags with sheeting displayed 66% higher mass loss on average compared to those without. Once termites had selected the substrate, mass loss increased consistently irrespective of litter traits.Quantifying the combined effects of sheeting frequency and differential mass loss, we found that fungus‐growing termites predominantly increased the mass loss of high‐nutrient litter. This was mainly due to additional mass loss in leaf litter, not stem litter, with tannin concentration being the primary predictor of enhanced overall decomposition by termites. This suggests termites ameliorate the otherwise adverse influence of plant secondary compounds on litter decomposition.Synthesis: Our results support the idea that fungus‐growing termites are generalists, as termites collected organic substrates with varying quality. The strong effect of phenolic compounds on sheeting rate implies that secondary compounds play an important role in termite substrate selection. The selective removal of substrates high in secondary compounds suggests fungus‐growing termites lift important constraints to microbial breakdown, potentially enhancing ecosystem‐level carbon and nutrient recycling rates. Termites play crucial roles in recycling organic matter across tropical biomes and our study highlights that the role of secondary compounds in their selection and detection in decomposition studies needs more attention [ABSTRACT FROM AUTHOR]

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Effects of dietary non-starch polysaccharides-degrading enzymes (NSPase) and phytase complex on performance, carcass, bone minerals, litter, and gene expression (IGF, IL-1β, IL-10, TLR-4, CPT1A) were determined in broilers fed corn-soybean nutrient-reduced diets. Totally, 1200 Ross-308 one-day-old broiler chicks were randomly assigned into 4 treatments, with 6 replicates of 50 birds each; (G1) Control group received nutrient- adequate diet without enzymes supplementation; (G2) received energy-reduced diet (-100 kcal/kg) with NSPase (100 g/ton Econase®) + phytase enzymes (100 g/ton Quantum Blue®; 5,000 FTU/g); (G3) received energy-reduced diet (-80 kcal/kg) with NSPase (250 g/ton Enziver®) + phytase enzymes (100 g/ton Phytonex®; 5,000 FTU/g); (G4) received as G3 diet with a 0.5% decrease in crude protein (CP). For all energy-reduced diets, the nutritional matrix of phytase with reductions of phosphorus (P) (0.15%), and calcium (Ca) (0.165%) was considered. Dietary NSPase and phytase supplementation to a low-energy diet significantly (P<0.05) enhanced body weights, weight gain, feed conversion ratio, and litter quality (lowered nitrogen, phosphorous, and calcium excretion in broiler manure), with constant bone mineralization. No significant effects (P>0.05) on carcass or blood biochemistry. Energy and CP-reduced diet showed better feed intake, immune organ weights, and mineral bioavailability by decreasing Alkaline phosphatase activity. Moreover, upregulated gene expression of IGF-1 in muscles, inflammatory cytokines (IL-1B and IL-10), immune-related genes (TLR-4) in the liver, and (CPT1A) responsible for energy production. Conclusively, dietary NSPase with phytase enzymes compensated for up to 0.5% CP, 100 kcal ME/kg, and 0.15% and 0.165% units of Av.P and total Ca, with improving broiler performance and environmental impacts. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effect of different levels of alkaline hydrolyzed feather meal (AHFM) on the performance, intestinal morphology, and meat oxidation of Arian broiler chickens from d 15 to 42. A total of 480 one-day-old chickens of two sexes (equal ratio) were randomly distributed among 24 pens (20 chicks per experimental unit). The four experimental diets contained different levels of feather meal (0, 2, 4, and 5 %), which were replicated six times. During the grower period, daily weight gain decreased and the feed conversion ratio increased at 4 and 5 % AHFM levels (P<0.05), also feed intake increased in birds fed on a 5 % AHFM diet (P<0.05). In the overall experimental period feeding 4 % AHFM decreased the body weight gain compared to control (P<0.05) and the feed intake was reduced in birds fed on 2 % AHFM (P<0.05). The feed conversion ratio has not been influenced by the level of AHFM 15-42 d. Diets with AHFM decreased the jejunum villi height, while this reduction in the ileum was observed at 4 and 5 % AHFM, and goblet cell density increased at 5 % AHFM (P<0.05). With the increase in the level of AHFM, the concentration of malondialdehyde in fresh breast, and thigh meat decreased so that the group receiving five percent of AHFM had the lowest concentration of malondialdehyde (P<0.01). The level of 5 % AHFM reduced the litter moisture (P<0.05) and the levels of AHFM did not affect the concentration of the litter ammonia. None of the mortality, production efficiency index, and feed cost per kilogram of live weight were significantly affected by experimental treatments. As a general conclusion, the use of AHFM reduced the body weight and increased the feed conversion ratio of Arian broilers without affecting the mortality rate and production efficiency index, although meat oxidative stability improved. [ABSTRACT FROM AUTHOR]

Litter enzyme dynamics are strongly shaped by litter, soil and microbial attributes during decomposition; however, the enzyme dynamics of leaf and root litter remain unresolved due to contrasting differences in rates and controls on leaf and root litter decomposition.Herein, we conducted a 784‐day field experiment to evaluate the relative importance of litter, alkaline soil and microbial attributes to enzyme activities and their C:N:P stoichiometry of leaf and root litter during decomposition under subtropical land use change in China.We found that only the C‐ and N‐acquiring enzyme activities of shrub leaves were greater than those of wood and crop, and there was no significant difference in P‐acquiring enzyme activity among the three species of leaves. Both the C‐ and P‐acquiring enzyme activities of crop roots were significantly lower than those of afforested lands (i.e. woodland and shrubland). The N‐acquiring activities of wood roots were significantly lower than those of shrub and crop. At the temporal dynamics, the C‐, N‐ and P‐acquiring enzyme activities of the leaves decreased with mass loss, which was affected by the shift in litter nutrients (e.g. N and P) and soil moisture during decomposition. In contrast, the three enzyme activities of roots increased with mass loss, largely due to the increase in microbial biomass of bacteria regulated by litter stoichiometry. The enzymatic C:nutrient (N and P) ratios declined with mass loss, but the enzymatic P:N ratios remained relatively constant with mass loss during the leaf litter decomposition. Whereas, both of the enzymatic C:nutrient ratios and enzymatic P:N ratios decreased with mass during the root litter decomposition. Our results showed that the enzymatic C:N:P stoichiometry of decaying leaves and roots was predominantly predicted by microbial biomass and bacterial biomass, respectively.Overall, we outlined the pattern of contrasting contributions of litter, soil and microbial attributes to enzyme dynamics during decomposition, which provided a framework for better understanding litter C, N and P dynamics in relation to microbial resource allocation strategy during decomposition. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

The increasingly significant adverse effects of climate change on broiler production require the use of suitable feeding strategies. This study was carried out to evaluate the effect of low-protein diets supplemented with different levels of dietary lysine on growth performance and welfare of broilers raised in tropical climates for 28 days. A total of 500 15-day-old Cobb 500 broiler chicks were randomly divided into 5 treatments with 5 replicates of 20 chickens each using a completely randomized design: chickens fed a standard lysine-free diet with high crude protein (CP) content (18.25%) (T+) or low CP content (15%) (T-) or low CP diet (15%) supplemented with lysine at rates of 0.1% (L1), 0.2% (L2), and 0.3% (L3). Growth performance, blood profile, and carcass composition were evaluated and analyzed. Gait abnormalities and litter quality were assessed at 38 and 45 days of age, respectively. Birds in the L2 and L3 treatments showed an improved body weight, weight gain, and feed conversion ratio (p < 0.05) compared to those in the other treatments. The thyroid hormone concentrations were higher (p < 0.05) in L2 and L3 treatments, and litter quality was better in all birds fed the low-protein diets supplemented with lysine. Conclusively, lysine supplementation at levels of 0.2 and 0.3% in a low-protein diet (15%) improved the growth performance and welfare of broilers in tropical climates. [ABSTRACT FROM AUTHOR]

Exploring how interactions between species evenness and dominant species identity affect litter decomposition processes is vital to understanding the relationship between biodiversity and ecosystem functioning in the context of global changes. We carried out a 127‐day litter decomposition experiment under controlled conditions, with interactions of four species evenness types (high, medium, low and single species) and three dominant species identity (Leymus chinensis, Serratula centauroides, Artemisia capillaris). After collecting the remaining litter, we estimated how evenness and dominant species identity affected litter mass loss rate, carbon (C) loss rate, nitrogen (N) loss rate and remaining litter C/N directly or indirectly, and assessed relative mixture effects (RMEs) on litter mass loss. The main results are shown as follows. (1) By generalized linear models, litter mass loss rate was significantly affected by evenness after 69‐day decomposition; N loss rate was affected by dominant species identity after 69‐day decomposition, with treatment dominated by Serratula centauroides being at least 9.26% higher than that dominated by any of other species; and remaining litter C/N was affected by the interactions between evenness and dominant species identity after 30‐, 69‐ and 127‐day decomposition. (2) Twenty‐three out of 27 RMEs were additive, and dominant species identity showed a significant effect on RMEs after 127‐day decomposition. (3) By confirmatory path analyses, litter mass loss rate was affected by dominant species identity directly after 127‐day decomposition, and by both species evenness and dominant species identity indirectly which was mediated by initial litter functional dispersion (FDis) after 30‐ and 69‐day decomposition; remaining litter C/N was affected by evenness indirectly which was mediated by initial litter FDis after 127‐day decomposition. These findings highlight the importance of evenness and dominant species identity on litter decomposition. The study provides insights into communities during retrogressive successions in semi‐arid grasslands in the context of global changes. [ABSTRACT FROM AUTHOR]

Below‐ground litter decomposition represents an important source of the limiting nutrients nitrogen (N) and phosphorus (P) to forest soils, but roots also immobilize these nutrients during the decomposition process.Despite clear implications for soil fertility, the rates and drivers of nutrient immobilization and release (as the percent of increase and decrease of the initial pool) from root litter remain poorly understood, especially in coarse roots (>2 mm diameter).To address this gap, we conducted a 7‐year field decomposition experiment using roots from three species, across five diameter classes (<1, 1–2, 2–5, 5–10 and 10–20 mm) in a temperate forest.Nitrogen dynamics were largely decoupled with P and carbon (C) over the course of the experiment, and both varied by species and root diameter. Roots released P to the surrounding soil within the first year of decomposition. In contrast, roots immobilized N for much longer, with the coarsest roots remaining a net N sink after 7 years. Long‐term N release was jointly controlled by initial nutrient and C quality, whereas P release and decomposition rate were better predicted by initial C quality. Initial root nutrients well predicted the difference between long‐term N versus P release.Synthesis. Our results highlight the fact that N and P dynamics should be considered separately when modelling nutrient release during root decomposition, and suggest that the functional diversity of below‐ground biomass may have considerable afterlife effects on the relative availability of N and P in soil. We conclude that root litter, especially coarse root litter, represents an underappreciated N sink in forest soils. [ABSTRACT FROM AUTHOR]

In riparian forests, litter decay provides essential energy and nutrients for both terrestrial and fluvial ecosystems. Litter mixing effects (LMEs) are crucial in regulating litter decay and nutrient dynamics, yet how LMEs change over time is unclear in riparian forests. In this study, leaf litter of three common species (Alnus sibirica Fisch. ex Turcz, Betula platyphylla Sukaczev, and Betula fruticosa Pall.) were mixed in an equal mass ratio and LMEs were measured for mass and nitrogen (N) remaining in whole litter mixtures over a 3-year period in a boreal riparian forest, northeastern China. LMEs were also assessed for component litter mass and N remaining by separating litter mixtures by species. During the decay of litter mixtures, antagonistic effects on mass and N remaining were dominant after one and two years of decay, whereas only additive effects were observed after three years. LMEs correlated negatively with functional diversity after the first and two years of decay but disappeared after three years. When sorting litter mixtures by species, non-additive LMEs on mass and N remaining decreased over incubation time. Moreover, non-additive LMEs were more frequent for litter of both B. platyphylla and B. fruticosa with lower N concentration than for A. sibirica litter with higher N concentration. These results indicate that incubation time is a key determinant of litter mixing effects during decay and highlight that late-stage litter mixture decay may be predicted from single litter decay dynamics in boreal riparian forests. [ABSTRACT FROM AUTHOR]

ABSTRACT: Between 3 and 20 wk of age (WOA), the effects of water access time and access to alfalfa during the rearing phase on the litter conditions, performance, and behavior of broiler breeder pullets was studied. A total of 480 female one-day-old chicks (Ross 308) were randomly assigned to 24 floor pens (20 pullets/pen) within a 3 × 2 factorial completely randomized block design. Between 3 and 20 WOA, pullets received water 1) between 07:30 am and 10:30 pm h (3HR), 2) in 2 periods between 07:30 am and 11:00 pm h and between 14:00 pm and 15:30 pm h (5HR), or 3) during the entire light period (8HR). Half of the pens had unlimited access to alfalfa straw (ALF+) or not (ALF-). Higher water use and water-to-feed ratios were observed in the 5HR and 8HR pullets compared to the 3HR pullets (P < 0.001), with no effect observed from unlimited alfalfa. Clear differences in water use throughout the day were observed for the different water strategies. The dry matter (DM) content in the litter was lower, and the litter friability and moisture scores were higher in the 5HR and 8HR than the 3HR pens (P < 0.001), with no differences in fresh feces DM. Alfalfa straw had no effect on litter DM content, fresh feces DM content, litter friability score, or litter moisture score. Feather cover score and feather and footpad contamination score were higher in 5HR and 8HR pullets than in 3HR pullets (P < 0.05), with no differences between the ALF+ and ALF- pullets. The 5HR and 8HR pullets showed increased pecking at alfalfa straw and drinking nipples, along with decreased foraging and perching than the 3HR pullets (P < 0.05). Additionally, ALF+ pullets showed a tendency for less object pecking behavior (P = 0.066) than ALF- pullets. In conclusion, the study demonstrated that extended access to water in breeder pullets increased water use, resulting in inferior litter quality, decreased feather cover, and decreased feather cover and footpad contamination. Moreover, unlimited access to alfalfa straw decreased object pecking behavior.

Individual tree species might affect underground soil properties to favor the decomposition of their own litter. However, in some studies, monospecific litter decomposed faster underneath multispecific canopies than under canopies of the same species as the litter, suggesting that plant diversity in the overstorey creates a more favorable decomposition microenvironment. We compared the decomposition rate of monospecific litter from eight temperate tree species under the crown of the same species as the litter (conspecific canopy), and a multispecific canopy formed by eight species. Using model selection, we determined the influence of the microenvironments, species, and litter chemistry on decomposition rates. The most robust model included the species and canopy type, but it differed only slightly from the model including only the species. Decomposition rates were significantly different among species and higher in conspecific canopy than multispecific canopy in all species. Models including specific leaf area and different combinations of chemical traits of the litter were less robust than the null model. These results show that the species origin of the litter was significantly more important than the microenvironment to explain litter decomposition rates. [ABSTRACT FROM AUTHOR]

Cage-free (CF) layer houses tend to have high particulate matter (PM) levels because of bedding/litter floor and the birds' activities, such as perching, dustbathing, and foraging on it. It has been reported that optimizing bedding management can potentially suppress PM levels in CF houses. The objectives of this study were to (1) test the effect of the top application of new bedding materials (BMs) on PM levels and (2) compare different BM PM reduction efficiencies. Small flake shavings (SFS), large flake shavings (LFS), and aspen wood chips (AWC) were top-dressed on the surface of the original litter (33-week-old litter) evenly in each of the BM treatment rooms at 20% volume of the original litter floor. The initial litter depths in the control, SFS, LFS, and AWC rooms were 4.6 ± 0.6, 4.8 ± 0.8 cm, 4.8 ± 0.8 cm, and 4.6 ± 0.9 cm, respectively. One room was used as a control without adding new BM. The results indicate that the top application of new bedding suppressed PM levels in all treatment rooms (p < 0.01). The PM2.5 reductions in the SFS, AWC, and LFS treatment rooms were 36.5%, 34.6%, and 28.9% greater than in the control room, respectively. The mitigation efficiencies were different between PM sizes. For instance, PM2.5, PM10, and TSP in the SFS room were lower than in the control room by 36.5%, 39.4%, and 38.7%, respectively. For litter quality, the moisture content was 18.0 ± 2.8, 20.0 ± 3.1, 20.6 ± 2.4, and 19.7 ± 4.2% in the control, SFS, LFS, and AWC rooms, respectively. Treatment rooms with 20% new BM had 10% higher litter moisture than the control room. The findings of this study reveal that the top application of new bedding on old litter is a potential strategy for reducing PM generation in CF houses. Further studies are warranted, such as regarding the effect of different ratios of new bedding on PM reduction, cost analysis, and verification tests in commercial CF houses. [ABSTRACT FROM AUTHOR]

Understanding the relative importance of climates at coarse scales and nitrogen (N) availability at fine scales in driving litter decomposition is crucial for ecosystem functioning. In this study, we explored the relative importance of coarse-scale climatic contrast (China vs. France) and local soil fertility contrast related to N availability in determining 'home-field advantage (HFA)' effects. Four tree-species litters from four forest types with contrasting chemical properties from China and France were reciprocally transplanted in a litterbag decomposition experiment. The Decomposer Ability Regression Test showed highly significant HFA effects for the Chinese litter (Castanopsis eyrei), that is, the most recalcitrant litter with low P and N contents, and marginally significant HFA effects for the French litter (Carpinus betulus), that is, the most labile litter with high P and N contents. The climatic contrast was more important in determining HFA effects than the N availability contrast. Our findings highlight the importance of climate in determining the occurrence of HFA effects that likely can be attributed to differences in soil weathering intensity driving soil P legacy, an important coarse-scale component of soil fertility. [ABSTRACT FROM AUTHOR]

Aims: Litter decomposition affects soil organic carbon storage, and nutrient addition alters exogenous nutrient availability in soil, thereby affecting the endogenous nutrient concentration and extracellular enzyme activity in litter. However, how above- and belowground litter decomposition responds to nutrient addition is not fully understood. Methods: We conducted a 7-yr field experiment with 5 levels (0, 1, 2.5, 5, and 12.5 g P m−2 yr−1) of phosphorus fertilization (P). Starting in the 6th year, we determine litter decomposition, nutrient elements, and enzyme activity to explore the response mechanisms of above- and belowground litter decomposition to P addition. Results: All levels of P addition increased the rate of aboveground litter decomposition, but only 2.5 g P m−2 yr−1 increased that of belowground litter. P addition increased the litter initial P and Mn contents, while decreased the C/P and N/P ratios of aboveground litter, which stimulated the activities of β-1,4-glucosidase and β-1,4-N-acetylglucosaminidase, thereby increasing the aboveground litter decomposition rate. The belowground litter decomposition was mainly inhibited by lignin content, and 2.5 g P m−2 yr−1 addition significantly decreased lignin content and increased the phenol oxidase activity, thereby accelerating the decomposition. P addition promoted the accumulation of P and the release of cellulose from aboveground litter and promoted the accumulation of calcium and the release of carbon from belowground litter. Conclusions: Different mechanisms of above- and belowground litter decomposition under P addition were driven by litter quality and enzyme activity, but moderate P addition increased semiarid grassland litter decomposition, which may contribute to low soil C sequestration. [ABSTRACT FROM AUTHOR]

Litter decomposition is a fundamental ecosystem process controlling the biogeochemical cycling of energy and nutrients. Using a 360-day lab incubation experiment to control for environmental factors, we tested how litter quality (low C/N deciduous vs. high C/N coniferous litter) governed the assembly and taxonomic composition of bacterial communities and rates of litter decomposition. Overall, litter mass loss was significantly faster in soils amended with deciduous (DL) rather than coniferous (CL) litter. Communities degrading DL were also more taxonomically diverse and exhibited stochastic assembly throughout the experiment. By contrast, alpha-diversity rapidly declined in communities exposed to CL. Strong environmental selection and competitive biological interactions induced by molecularly complex, nutrient poor CL were reflected in a transition from stochastic to deterministic assembly after 180 days. Constraining how the diversity and assembly of microbial populations modulates core ecosystem processes, such as litter decomposition, will become increasingly important under novel climate conditions, and as policymakers and land managers emphasize soil carbon sequestration as a key natural climate solution. [ABSTRACT FROM AUTHOR]

Abstract Exploring how interactions between species evenness and dominant species identity affect litter decomposition processes is vital to understanding the relationship between biodiversity and ecosystem functioning in the context of global changes. We carried out a 127‐day litter decomposition experiment under controlled conditions, with interactions of four species evenness types (high, medium, low and single species) and three dominant species identity (Leymus chinensis, Serratula centauroides, Artemisia capillaris). After collecting the remaining litter, we estimated how evenness and dominant species identity affected litter mass loss rate, carbon (C) loss rate, nitrogen (N) loss rate and remaining litter C/N directly or indirectly, and assessed relative mixture effects (RMEs) on litter mass loss. The main results are shown as follows. (1) By generalized linear models, litter mass loss rate was significantly affected by evenness after 69‐day decomposition; N loss rate was affected by dominant species identity after 69‐day decomposition, with treatment dominated by Serratula centauroides being at least 9.26% higher than that dominated by any of other species; and remaining litter C/N was affected by the interactions between evenness and dominant species identity after 30‐, 69‐ and 127‐day decomposition. (2) Twenty‐three out of 27 RMEs were additive, and dominant species identity showed a significant effect on RMEs after 127‐day decomposition. (3) By confirmatory path analyses, litter mass loss rate was affected by dominant species identity directly after 127‐day decomposition, and by both species evenness and dominant species identity indirectly which was mediated by initial litter functional dispersion (FDis) after 30‐ and 69‐day decomposition; remaining litter C/N was affected by evenness indirectly which was mediated by initial litter FDis after 127‐day decomposition. These findings highlight the importance of evenness and dominant species identity on litter decomposition. The study provides insights into communities during retrogressive successions in semi‐arid grasslands in the context of global changes.

Abstract Background The study aimed to evaluate the influence of wheat straw and different coffee husk (CHs) levels in pellet bedding on its quality, broiler chickens’ performance, meat quality, and welfare indicators. In total, 200 Ross 308 chickens were divided into 4 groups: C – control with wheat straw pellet; CH10 – pellet with 10% CHs, CH25 – pellet with 25% CHs, and CH50 – pellet with 50% CHs. During 42 days of rearing, each bedding's physicochemical features were analyzed. The production results were controlled, and the footpad dermatitis, hock burns, and feather quality were assessed. From chosen birds, carcass composition was analyzed, as well as the qualitative features (color, water-holding capacity, drip loss) and breaking bone strength. Results The bedding material and rearing days influenced the content of dry matter, crude fiber, nitrogen, phosphorus, potassium, NDF, ADF, and pH. The results were inconclusive. The increasing trends in nitrogen, phosphorus, and potassium content were noticed at the end of rearing. Strong coefficient determination in bedding features was found (0.580 – 0.986). The pellet with CHs had no adverse effect on the growth performance of broilers. In the CH50 group, a lower fat percentage was found. A beneficial effect on water-holding capacity was noticed in leg muscles from CH10 and pectoral muscles from CH25. A significant decrease was found in footpad dermatitis incidence in groups CH25 and CH50. Conclusions It can be concluded that CHs reuse in broilers as the pellet bedding material is possible due to the beneficial effect on some meat quality features and no adverse effect on the performance of broiler chickens. The positive impact on lower foot pad dermatitis incidence indicated the possibility of using CHs in pellet bedding.

Cage-free (CF) layer houses tend to have high particulate matter (PM) levels because of bedding/litter floor and the birds’ activities, such as perching, dustbathing, and foraging on it. It has been reported that optimizing bedding management can potentially suppress PM levels in CF houses. The objectives of this study were to (1) test the effect of the top application of new bedding materials (BMs) on PM levels and (2) compare different BM PM reduction efficiencies. Small flake shavings (SFS), large flake shavings (LFS), and aspen wood chips (AWC) were top-dressed on the surface of the original litter (33-week-old litter) evenly in each of the BM treatment rooms at 20% volume of the original litter floor. The initial litter depths in the control, SFS, LFS, and AWC rooms were 4.6 ± 0.6, 4.8 ± 0.8 cm, 4.8 ± 0.8 cm, and 4.6 ± 0.9 cm, respectively. One room was used as a control without adding new BM. The results indicate that the top application of new bedding suppressed PM levels in all treatment rooms (p < 0.01). The PM2.5 reductions in the SFS, AWC, and LFS treatment rooms were 36.5%, 34.6%, and 28.9% greater than in the control room, respectively. The mitigation efficiencies were different between PM sizes. For instance, PM2.5, PM10, and TSP in the SFS room were lower than in the control room by 36.5%, 39.4%, and 38.7%, respectively. For litter quality, the moisture content was 18.0 ± 2.8, 20.0 ± 3.1, 20.6 ± 2.4, and 19.7 ± 4.2% in the control, SFS, LFS, and AWC rooms, respectively. Treatment rooms with 20% new BM had 10% higher litter moisture than the control room. The findings of this study reveal that the top application of new bedding on old litter is a potential strategy for reducing PM generation in CF houses. Further studies are warranted, such as regarding the effect of different ratios of new bedding on PM reduction, cost analysis, and verification tests in commercial CF houses.

Leaf litter decomposition is a significant ecosystem process for streams' energy provisioning, while species‐specific decomposition rates often form a continuum from slow to fast decomposing species allowing for resources' availability to stream consumers over a longer time period after leaf fall. Leaf litter mixtures in streams typically comprise leaf species varying in their traits, allowing for litter diversity effects on decomposition. At the same time, agricultural land use, habitat characteristics, water quality and invertebrate composition modulate leaf litter decomposition. To identify leaf litter diversity effects and disentangle the roles of agricultural intensity, habitat characteristics, water quality and invertebrate composition for leaf litter processing in streams, we quantified leaf litter decomposition of three leaf species covering a gradient from slow to fast decomposing species, tested either individually or as a three‐species mixture. The study was conducted over 21 days across 18 streams with a gradient of agricultural intensity (percent agricultural land use) in their catchments. We found leaf litter diversity effects in terms of complementarity under low to intermediate agricultural intensity, given that slow decomposing leaf species decomposed almost twice as fast in the three‐species mixture compared to the observations on individual leaf species. This leaf litter diversity effect decreased with increasing agricultural intensity, suggesting that agriculture weakens the biodiversity–ecosystem functioning relationship. However, pathways by which agriculture affected decomposition differed between single‐species and mixed‐species scenarios. For the single‐species scenario, negative effects of agriculture appeared to be mediated through effects on the proportion of sensitive detritivore species and altered habitat characteristics. For the mixed‐species scenario, altered water quality negatively affected the proportion of sensitive detritivore species, in turn reducing the diversity effect on functioning. Our results suggest that the weakened biodiversity–ecosystem functioning relationship under increasing agricultural intensity might be a significant factor threatening carbon cycling and food web integrity in streams. [ABSTRACT FROM AUTHOR]

Species‐rich forests can produce litter of varying carbon (C) and nitrogen (N) composition (i.e. quality), which can affect decomposition and play a central role in long‐term soil organic carbon (SOC) accumulation. However, how differences in litter quality affect SOC decomposition and formation remains unclear over the full litter decomposition trajectory.We followed the in situ complete decomposition of added 13C‐labelled high‐ (low C:N) and low‐quality (high C:N) leaf‐litter and its effect on particulate organic matter (POM) and mineral‐associated organic matter (MAOM) fractions over 2 years in a natural subtropical forest.We found that during early stages of decomposition, low‐quality litter inputs decreased SOC via a positive priming effect (i.e. new C inputs favoured decomposition of native SOC), but these SOC losses were offset by SOC gains observed via a negative priming effect during decomposition of high‐quality litter. In contrast, this pattern reversed during late stages of decomposition—SOC losses via a positive priming effect induced by high‐quality litter were offset by SOC gains via a negative priming effect induced by low‐quality litter. Over the full decomposition of litter, both high‐ and low‐quality litter stimulated microbial breakdown of SOC tied to POM, but also replenished more persistent SOC that associated with soil minerals (MAOM). Altogether, we observed that low‐quality litter formed twice as much new SOC as high‐quality litter (24% vs. 12% of added litter‐C). We extend the notion of the priming effect from primarily a negative role promoting losses of native SOC, to a functional role that can replenish persistent SOC.Synthesis. Our measurements raise the possibility that, in species‐rich forests, high‐ and low‐quality litter decomposition play opposite but dynamically complementary roles in renewing POM—both by inducing its decomposition and formation—while exclusively favouring MAOM formation, which can help explain how differences in litter quality favour SOC accumulation and persistence. Global change factors that shift plant community composition may ultimately affect the fate of soil C, as changes in litter quality may force soil transitions from sinks to sources or sources to sinks of atmospheric CO2. [ABSTRACT FROM AUTHOR]

Background: The study aimed to evaluate the influence of wheat straw and different coffee husk (CHs) levels in pellet bedding on its quality, broiler chickens' performance, meat quality, and welfare indicators. In total, 200 Ross 308 chickens were divided into 4 groups: C – control with wheat straw pellet; CH10 – pellet with 10% CHs, CH25 – pellet with 25% CHs, and CH50 – pellet with 50% CHs. During 42 days of rearing, each bedding's physicochemical features were analyzed. The production results were controlled, and the footpad dermatitis, hock burns, and feather quality were assessed. From chosen birds, carcass composition was analyzed, as well as the qualitative features (color, water-holding capacity, drip loss) and breaking bone strength. Results: The bedding material and rearing days influenced the content of dry matter, crude fiber, nitrogen, phosphorus, potassium, NDF, ADF, and pH. The results were inconclusive. The increasing trends in nitrogen, phosphorus, and potassium content were noticed at the end of rearing. Strong coefficient determination in bedding features was found (0.580 – 0.986). The pellet with CHs had no adverse effect on the growth performance of broilers. In the CH50 group, a lower fat percentage was found. A beneficial effect on water-holding capacity was noticed in leg muscles from CH10 and pectoral muscles from CH25. A significant decrease was found in footpad dermatitis incidence in groups CH25 and CH50. Conclusions: It can be concluded that CHs reuse in broilers as the pellet bedding material is possible due to the beneficial effect on some meat quality features and no adverse effect on the performance of broiler chickens. The positive impact on lower foot pad dermatitis incidence indicated the possibility of using CHs in pellet bedding. [ABSTRACT FROM AUTHOR]

Standing litter decomposition generally plays important roles in biogeochemical cycling in wetlands. By contrast with dew, the role of solar radiation receives less attention in humid ecosystems. Here, we determined aerial decomposition dynamics of five litters in a freshwater wetland in the Yangtze-Huaihe basin. Moreover, we analyzed the role of dew and sunlight in the decomposition of Phragmites australis culm and leaf based on a simulation experiment. After 360 days of field decomposition, the mass loss ranged from 31.1% to 80.7%, significantly relating to litter nutrient, cellulose, and lignin concentrations. In the simulation experiment, the sunlight treatment rather than the dew treatment facilitated mass loss of culm, and the mass loss in the dew + sunlight treatment was greater than the sunlight treatment. For the leaf, both sunlight and dew treatments increased mass loss, and the mass loss in the dew + sunlight treatment was greater relative to that in the dew and the sunlight treatments. In addition, the mass loss was not significantly different between the sterilization and the control treatments, irrespective of tissue. However, the sterilization + sunlight treatment increased the mass loss of culm, despite no significant effects on the leaf. These findings confirm the importance of standing litter in biogeochemical cycling of freshwater wetlands in the Yangtze-Huaihe basin. Moreover, this study highlights the important role of sunlight and its combined action with dew in regulating litter decomposition in humid ecosystems, where the specific role varies with litter quality. [ABSTRACT FROM AUTHOR]

The aim of this study was to reveal the decomposition differences of kiwifruit litters with different qualities and verify the "Initial Litter Quality Hypothesis". This study took litters of 'Jinkui' and 'Hort-16A' kiwifruit as the research objects, and carried out in situ decomposition experiments. The decomposition rate, nutrients release process, and soil enzyme activities were analyzed. In this study, the litter of 'Hort-16A' kiwifruit decomposed faster than the litter of 'Jinkui' kiwifruit. The decomposition time was positively correlated with the initial concentration of C of the litters, but negatively correlated with the concentrations of N and P. Except for P and Mn, the dynamic trends of the nutrient concentrations were similar during the litter decomposition of 'Jinkui' and 'Hort-16A' kiwifruit. After 180 days of decomposition, about 85%~95% of the initial concentrations of the macro-elements of the 'Hort-16A' kiwifruit litter were released. The dynamic trends of protease activities were similar, but that of sucrase, β-1,4-glucosidase, polyphenol oxidase, and phosphatase were different. In conclusion, the litter quality of kiwifruit affects the decomposition rate, and the difference in decomposition rate in turn affects the dynamic processes of nutrient release and soil enzyme activity. This study provides evidence for the "Initial Litter Quality Hypothesis" in the orchard ecosystem. [ABSTRACT FROM AUTHOR]

Land-use changes affect terrestrial ecosystem carbon (C), nitrogen (N), and phosphorus (P) dynamics directly by altering above- and belowground litter inputs and decomposition, although the determining factors and their linkage to soil C, N, and P pools remain limited. Here, we investigated litter, soil, and microbial attributes during leaf and fine-root decomposition linked with soil C, N, and P pools under subtropical land-use change (that is, cropland, shrubland, and woodland). We found that leaf litter decomposed faster in shrubland than in woodland and cropland, while the fine root of cropland decomposed more than those of shrubland and woodland. Leaf and fine-root decomposition was not correlated, whereas leaf and fine-root litter quality was positively correlated. Leaf litter decomposition was considerably dependent on litter quality and soil moisture, whereas fine-root decomposition was predominantly predicted by bacterial biomass. Litter C quality in afforested lands (woodland and shrubland) substantially stimulated soil organic C accumulation primarily by the input of new fine-root-derived soil organic C. Soil total N accumulation in woodland was tightly associated with litter quality of fine root and microbial attributes, but soil total P formation in shrubland was strongly correlated with leaf litter quality and microbial attributes. These findings indicated that the variations in decomposition of leaf and fine root were mediated by different combinations of litter, soil, and microbial traits, which caused the difference in the soil C, N, and P accumulation following land-use change. Overall, our results revealed contrasting dynamics of above- and belowground litter decomposition, uncovered diverse influences on soil C, N, and P pools, and provided novel insights into accurately predicting soil C, N, and P dynamics after afforestation. [ABSTRACT FROM AUTHOR]

Litter decomposition plays a pivotal role in carbon (C) and nutrient cycling in terrestrial ecosystems. However, little is known about the litter decomposition processes and nutrient dynamics in urban green space. In this study, the decomposition and nutrient dynamics of leaf litter and fine roots from Cinnamomum officinarum Nee ex Wall. and Elaeocarpus decipiens Hemsl. were studied in an urban forest in subtropical China. The results showed that the leaf litter mass loss, and nitrogen (N) and phosphorus (P) mineralization of E. decipiens were faster than that of C. officinarum in the first 180 days, but in the whole decomposition period, the leaf litter decomposition constant of C. officinarum was higher than that of E. decipiens. There was no difference in fine root decomposition constant and P mineralization, although the fine root N immobilization was higher relative to C. officinarum during the 90th to 270th days. Additionally, both the leaf litter mass loss, decomposition rate, and nutrient mineralization were faster than fine roots for these two tree species. The soil microbial biomass showed positive effects on leaf litter decomposition and negative effects on fine root decomposition. The correlation analysis indicated that initial litter quality, soil physicochemical properties, and microbial activity mainly affected early-stage litter decomposition and nutrient mineralization. Also, the leaf litter production and N and P storages of E. decipiens were higher than that of C. officinarum, suggesting faster decomposition rate and nutrient return for E. decipiens leaf litter. Consequently, we propose that tree species with fast nutrient return, such as E. decipiens, could be introduced to urban green space with pervious surfaces in respect of the nutrient balance. This work improves the understanding of litter decomposition and nutrient cycling and promotes the management for urban green space. [ABSTRACT FROM AUTHOR]

Litter quality has long been associated with demographic parameters of Collembola populations. However, little is known about the capacity of Collembola to perceive and seek better litter quality. To address this gap, three complementary laboratory experiments were carried out with the Collembola Folsomia candida. First, populations were fed on three different types of leaf litters (Quercus pubescens, Acer opalus and Prunus avium) and a control (agar‐agar‐brewer's yeast mixture) for 6 weeks to assess their impacts on demography (reproduction rate and population size). Second, the body length of individuals differentially fed with the same four types of resources was measured to assess a functional trait that can potentially affect movement parameters such as prospected area or foraging speed. Third, F. candida single individuals were exposed to the same litter quality gradient and placed at an increasing distance from the litter (from 1 to 5 cm). For 10 min, their foraging behaviour was recorded which included prospected area, foraging speed, perception distance and success in reaching the litter (foraging success). As expected, low‐quality litter (i.e. Q. pubescens) contributed to low population growth compared to the control treatment and the high‐quality litters (P. avium and A. opalus). In the third experiment, the probability of finding the resource was negatively correlated to the distance, but was unrelated to the litter quality and the Collembola body length. When resource was perceived, F. candida was able to switch from non‐directional to directional movements, with a large variability in the perception distance from a few millimetres to several centimetres. Taken together, our results indicate that litter quality plays a relevant role in Collembola demographic parameters once the population settles on litter patch, but not on foraging behaviour to select high‐quality resources. [ABSTRACT FROM AUTHOR]

Changes in nitrogen (N) deposition and litter mixtures have been shown to influence ecosystem processes such as litter decomposition. However, the interactive effects of litter mixing and N‐deposition on decomposition process in desert regions remain poorly identified. We assessed the simultaneous effects of both N addition and litter mixture on mass loss in a litterbag decomposition experiment using six native plants in single‐species samples with diverse quality and 14‐species combinations in the Gurbantunggut Desert under two N addition treatments (control and N addition). The N addition had no significant effect on decomposition rate of single‐species litter (expect Haloxylon ammodendron), whereas litter mass loss and decomposition rate differed significantly among species, with variations positively correlated with initial phosphorus concentration and negatively correlated with initial lignin concentration. After 18 months, the average mass loss across litter mixtures did not overall differ from those predicted from single species either in control or N addition treatments, that is, mixing of different species had no non‐additive effects on decomposition. The N addition, however, did modify the direction of mixture effects and interacted with incubation time. Added N transformed synergistic effects of litter mixtures to antagonistic effects on mass loss after 1 month of decomposition, while transforming neutral effects of litter mixture to synergistic effects after 6 months of decomposition. Our results demonstrated that initial chemical properties played an important role in litter decomposition, while no effects of litter mixture on decomposition process in this desert region. The N addition altered the litter mixture effects on mass loss with incubation time, implying that increased N deposition in the future may have profound effects on carbon turnover to a greater extent than previously thought in desert ecosystems. [ABSTRACT FROM AUTHOR]

Research has indicated that introducing Aralia elata into larch plantations forms an agroforestry system which could provide economic benefits for local farmers and improve degraded soils. However, the impact of litter mixtures on soil chemical and microbial properties in this agroforestry system are unclear, which limits efficient management of the agroforestry system. A 365-d incubation experiment examined the effect of litter mixtures of different proportions of larch (L) and A. elata (A) on soil chemical and microbial properties. The results show that levels of mineral N, available P, microbial biomass carbon and nitrogen, cumulative C mineralization, and activities of hydrolases and oxidases increased with an increase of A. elata in the litter mixtures. Concentration of total soil carbon, nitrogen, and phosphorous did not change (except for total nitrogen). Compared with larch litter alone, levels of mineral N, available P, microbial biomass carbon and nitrogen, cumulative C mineralization, and the activities of hydrolases and oxidases increased by 7.6–433.5%. Most chemical and microbial properties were positively correlated with mixed litter proportions and the initial levels of N, P, K, Ca, Mg, Mn, Zn and Cu in the litter, while negatively correlated with the initial concentrations of C, Fe and lignin, C/N and lignin/N ratios. The results indicate that A. elata litter can improve degraded larch soil and the degree depends on the proportion of A. elata litter in the litter mixtures. [ABSTRACT FROM AUTHOR]

Abstract Litter quality has long been associated with demographic parameters of Collembola populations. However, little is known about the capacity of Collembola to perceive and seek better litter quality. To address this gap, three complementary laboratory experiments were carried out with the Collembola Folsomia candida. First, populations were fed on three different types of leaf litters (Quercus pubescens, Acer opalus and Prunus avium) and a control (agar‐agar‐brewer's yeast mixture) for 6 weeks to assess their impacts on demography (reproduction rate and population size). Second, the body length of individuals differentially fed with the same four types of resources was measured to assess a functional trait that can potentially affect movement parameters such as prospected area or foraging speed. Third, F. candida single individuals were exposed to the same litter quality gradient and placed at an increasing distance from the litter (from 1 to 5 cm). For 10 min, their foraging behaviour was recorded which included prospected area, foraging speed, perception distance and success in reaching the litter (foraging success). As expected, low‐quality litter (i.e. Q. pubescens) contributed to low population growth compared to the control treatment and the high‐quality litters (P. avium and A. opalus). In the third experiment, the probability of finding the resource was negatively correlated to the distance, but was unrelated to the litter quality and the Collembola body length. When resource was perceived, F. candida was able to switch from non‐directional to directional movements, with a large variability in the perception distance from a few millimetres to several centimetres. Taken together, our results indicate that litter quality plays a relevant role in Collembola demographic parameters once the population settles on litter patch, but not on foraging behaviour to select high‐quality resources.

Abstract Changes in nitrogen (N) deposition and litter mixtures have been shown to influence ecosystem processes such as litter decomposition. However, the interactive effects of litter mixing and N‐deposition on decomposition process in desert regions remain poorly identified. We assessed the simultaneous effects of both N addition and litter mixture on mass loss in a litterbag decomposition experiment using six native plants in single‐species samples with diverse quality and 14‐species combinations in the Gurbantunggut Desert under two N addition treatments (control and N addition). The N addition had no significant effect on decomposition rate of single‐species litter (expect Haloxylon ammodendron), whereas litter mass loss and decomposition rate differed significantly among species, with variations positively correlated with initial phosphorus concentration and negatively correlated with initial lignin concentration. After 18 months, the average mass loss across litter mixtures did not overall differ from those predicted from single species either in control or N addition treatments, that is, mixing of different species had no non‐additive effects on decomposition. The N addition, however, did modify the direction of mixture effects and interacted with incubation time. Added N transformed synergistic effects of litter mixtures to antagonistic effects on mass loss after 1 month of decomposition, while transforming neutral effects of litter mixture to synergistic effects after 6 months of decomposition. Our results demonstrated that initial chemical properties played an important role in litter decomposition, while no effects of litter mixture on decomposition process in this desert region. The N addition altered the litter mixture effects on mass loss with incubation time, implying that increased N deposition in the future may have profound effects on carbon turnover to a greater extent than previously thought in desert ecosystems.

A few studies indicated a possible role of arbuscular mycorrhizal fungi (AMF) in leaf litter decomposition. Information about these fungi in leaf litter is limited by the availability of techniques to recover them from such substrates. In the present study we aimed to (i) test an alternative approach for AMF recovery from litter; (ii) investigate if the AMF community structure in leaf litter differs between plant species; (iii) assess whether glomoid spore type might be more abundant in litter and (iv) determine whether litter quality and soil chemical parameters influence AMF communities. Leaves and soil were collected in three areas in the Brazilian Atlantic Forest. AMF were obtained from the leaves using a moist chamber approach. AMF communities were evaluated for their species richness, abundance, and diversity. In addition, the influence of soil chemical properties and litter quality on the structure of AMF communities was evaluated. Thirteen AMF species representing the genera Acaulospora, Entrophospora, Diversispora, Gigaspora, and Glomus, were recovered from leaves. The highest richness was observed in Ziziphus joazeiro leaves at Fazenda Sapé, whereas the highest diversity was found in the leaves of Hymenaea courbaril at Flona. AMF communities were influenced by litter quality and the P content of the soil. Our data show that this alternative approach for recovering AMF from the litter was successful in detecting communities inhabiting tropical conditions. This pilot research is an essential attempt to address the gap of knowledge about the occurrence of AMF in leaf litter and delimit future strategies to assess their function in this substrate. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the use of sunflower hull, a food industry residue, as a litter material in broiler meat production. In the study, the effects of sunflower hull on growth performance, litter quality and animal welfare were compared with large particle wood shaving, fine sawdust, rice hull and straw, which are commonly used in chicken meat production. In total, 5000 day-old broiler chicks were used in the experiment, 1000 day-old chicks in each group. Birds in all experimental groups were kept in same poultry house under standard conditions for broiler chickens, except for litter. All birds were fed with commercial broiler feed throughout the experiment. The effect of different litter materials on live weight was found to be no significant, and no difference was detected between groups in terms of mortality rate (P>0.05). In general, number of animals having foot pad lesions were found to be greater than animals having hock joint lesions in all birds. No animals were found with score levels of 7 and 8, which are the most severe (worst) breast and abdomen dirtiness levels. Litter pH and humidity values of sun flower hulls were found to be significantly lowest while it was found to be greatest in straw litter material (P<0.001). In conclusion; it can be said that the sunflower hull could be used as a litter material in broiler meat production without negatively affected the performance. [ABSTRACT FROM AUTHOR]

Plant litter is not only the major component of terrestrial ecosystem net productivity, the decomposition of which is also an important process for the returns of elements, including sodium (Na) and aluminum (Al), which can be beneficial or toxic for plant growth. However, to date, the global characteristics and driving factors of Na and Al concentrations in freshly fallen litter still remain elusive. Here, we evaluated the concentrations and drivers of litter Na and Al with 491 observations extracted from 116 publications across the globe. Results showed that (1) the average concentrations of Na in leaf, branch, root, stem, bark, and reproductive tissue (flowers and fruits) litter were 0.989, 0.891, 1.820, 0.500, 1.390, and 0.500 g/kg, respectively, and the concentrations of Al in leaf, branch, and root were 0.424, 0.200 and 1.540 g/kg, respectively. (2) mycorrhizal association significantly affected litter Na and Al concentration. The highest concentration of Na was found in litter from trees associated with both arbuscular mycorrhizal fungi (AM) and ectomycorrhizal fungi (ECM), followed by litter from trees with AM and ECM. Lifeform, taxonomic, and leaf form had significant impacts on the concentration of Na and Al in plant litter of different tissues. (3) leaf litter Na concentration was mainly driven by mycorrhizal association, leaf form and soil phosphorus concentration, while leaf litter Al concentration was mainly controlled by mycorrhizal association, leaf form, and precipitation in the wettest month. Overall, our study clearly assessed the global patterns and influencing factors of litter Na and Al concentrations, which may help us to better understand their roles in the associated biogeochemical cycles in forest ecosystem. [ABSTRACT FROM AUTHOR]

Purpose: Plant domestication altered leaf litter quality. Since litter traits relate to soil functions and organisms (i.e., litter decomposition and soil decomposer communities), in this study we explore if domestication-induced changes in litter quality have affected their decomposability, and bacterial, fungal, and nematode communities in the soil. Methods: We collected leaf litter from herbaceous crops and their wild progenitors, and measured litter chemical and physical traits. Then, we performed a litter decomposition assay on a common soil. After three months of litter incubation, we measured mass loss, nematode richness and community composition in ten crops. We also measured soil bacterial and fungal richness and community composition in six crops. Results: Domesticated litters had less carbon (C) and leaf dry matter content (LDMC), which accelerated decomposition in comparison to wild litters. Fungal richness was higher in microcosms incubated with domesticated litters, while the effects of domestication on bacterial richness differed among crops. Domestication did not affect nematode richness. The effects of domestication on bacterial and fungal community compositions differed among crops. Soils with domesticated litters tended to have nematode communities with a higher abundance of bacterial feeding nematodes, in comparison to soils fed with wild litters. Conclusion: Domestication altered decomposition at different levels. Leaf litter decomposability increased with domestication, which might alter resource inputs into the soil. Feeding soils with domesticated litters had idiosyncratic effects on soil microbes, but consistent effects on soil nematodes. Overall, domestication altered the linkages between crop residues and soil communities differently for bacteria, fungi, and nematodes. [ABSTRACT FROM AUTHOR]

Background and aims: Decomposition of leaf and root litter contributes large amounts of phosphorus (P) to soil and is strongly determined by litter quality, morphology, and microbial activity, but the individual and interactive roles of these factors remain underexplored. Methods: To fill this gap, field litter decomposition experiment was conducted by collecting leaf and fine root litters (< 2 mm) of crop (from cropland), shrub (from shrubland) and wood (from woodland) and placing the litters into woodland soil for 2 years in subtropical China, in order to evaluate effects of the above factors on leaf and fine root litter P loss of three species among different decomposition stages. Results: Leaf litter P loss was positively correlated with root P loss, and both were primarily controlled by microbes. Leaf litter P loss was more affected by litter quality, while root litter P loss was more affected by morphology during whole decomposition. However, morphology and litter quality were also important controls of leaf P loss at mid-to-late stages and of root P loss at early-to-mid stages. Conclusion: Our results highlighted that microbes exerted dominant controls with different importance of litter morphology and litter quality during different decomposition, which weakened the coordination between leaf and root decomposition. Overall, different regulation processes of leaf and root litter P loss and associated drivers at different decomposition stages provided novel insight into accurately predicting litter decomposition related to nutrient cycling under future afforestation. [ABSTRACT FROM AUTHOR]

Litter decomposition rates are determined by the interplay of climate, decomposer organisms and litter quality. It has been suggested that the decomposer community may be locally adapted to litter quality, providing a home‐field advantage (HFA) resulting in accelerated decomposition of local compared to non‐local litter, after accounting for decomposition differences due to litter quality and the functional capacity of microorganisms. Although widely tested in forests, this hypothesis remains controversial and lacks support of its generality across climates.We therefore tested the HFA hypothesis for litter decomposition in four contrasting ecosystems along an extensive climatic gradient in Chile, using a translocation experiment involving litter from 20 species. In addition to comparing mass loss, we adopted a novel way to disentangle decomposer effects from climate effects, based on loss rates of elements that are actively released from the litter by decomposers during its breakdown versus elements that are simply leached by precipitation. We used the ratios of nitrogen and potassium losses (N/K loss) and phosphorus and potassium losses (P/K loss) to unravel the relative role of microbial breakdown (N and P loss) versus physical leaching (K loss) along the climate gradient. Thus, at each site, we tested whether litter mass loss, N/K loss and P/K loss presented an additional loss due to a HFA for local compared to non‐local litter.Across a wide range of environments and litter types, our findings unequivocally contradicted the HFA hypothesis. We observed no significantly positive HFA along the gradient; however, litter quality and the general ability of the decomposer community influenced litter decomposition much more strongly than origin or location of the litter.Our study questions the applicability of the HFA for litter decomposition and calls for more studies that include a large range of climatic conditions to understand the context‐dependency of HFA. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Decomposition rates are an important component of carbon sequestration rates in soils, potentially mitigating future climate change. Here we aim to better understand decomposition's relationship with temperature in natural conditions.In snow‐tussock grassland dominated by Chionochloa rubra on Mount Tongariro, Tongariro National Park, New Zealand, we measured decomposition of Chionochloa leaf litter along an ≈ 700 m altitudinal gradient, as a space‐for‐temperature experiment, representing 4.2°C of warming. We examined decomposition rates in a full reciprocal translocation of litter bags between eight plots as both the origin of eight litter types and the eight destinations of plating out of litter bags, over 4 years using six replicates, and modelled their relationships to environmental variates.Litter decomposed progressively over time, but at the same rate along the altitudinal gradient. There was no home‐field advantage. In terms of litter quality, decomposition rates were related only to litter lignin, or fibre or litter N. Only decomposition at Year 4, and that only when organised by litter destination, showed a relationship to mean annual temperature jointly with soil C, and this was only weak and implausible. When studied across the full reciprocal transplant, there were no significant interactions between Origin and Destination data with or without Years. Therefore litter from each plot decomposed at the same rate as other plots' litter at all altitudes, allowing for small, often irregular differences in litter quality and micro‐environment.Despite the few modelled differences, decomposition rates show no plausible trends in our altitude‐for‐temperature substitution. We suggest this may be a universal finding, except perhaps under different moisture regimes. Thus, under projected climate warming scenarios, changes in temperature will not directly affect decomposition rates, and cannot influence C sequestration in nature. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

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The mechanical resistance of plant leaves to herbivores and physical disturbances have a lasting legacy impact on leaf-litter decomposition rates and nutrient leaching. However, in the past, leaf mechanics were seldom considered as key factors in regulating ecological processes related to leaf-litter decomposition. In this paper, we explored the physical strength traits of leaves, which are essential components of plant functional traits. These traits are primarily manifested through three mechanical properties: force to punch, force to tear, and work to shear. We discuss their potential applications in order to better understand trait-based factors influencing leaf-litter decomposition as well as other ecological processes. Their ecological connections and distinctions from other widely discussed plant functional traits relevant to decomposition processes were also addressed. By conducting an extensive literature survey, we further showed the importance and irreplaceability of leaf physical strength traits as potential predictors of leaf-litter decomposability compared with commonly measured plant chemical traits (e.g., carbon, nitrogen, and lignin). Recognizing leaf mechanics as vital yet previously overlooked determinants of ecological processes governing leaf-litter decomposition, we propose incorporating this set of traits into existing predictive models to improve the explanatory capability of plant species traits in regulating leaf-litter decomposition processes.

The decomposition of plant litter and animal dung is the key processes of nutrient cycling and has been studied in a wide range of grassland ecosystems. However, most studies focus on the separate processes of either plant litter or animal dung decomposition, while the interactions between these two processes, which occur in grazed grassland ecosystems, are rarely studied. We conducted an experiment in a semi-arid grassland in Central Inner Mongolia, to examine the mass loss rates and chemical composition changes of two plant litter species and three herbivore dung types separately or in combination over a 2-year period. Twenty litterbag treatments were used to represent 2 treatments of plant litter only, 6 treatments of herbivore dung only at two addition levels, and 12 treatments of litter and dung combinations. We found that horse dung had the biggest mass loss rate, followed by cattle dung and sheep dung, either separately or mixed with plant litter. Dung addition promoted the mass loss, nitrogen release and fiber fraction (hemicellulose, cellulose and lignin) loss of plant litter, and the promotion was strongest for cattle dung, weakest for sheep dung, and stronger at high dung addition levels and in the early stages. However, the effect of litter addition on dung decomposition, a negative effect, was significant only when the dung proportion was low in the litter and dung mixture (that is, in the treatment of 10 g litter + 6 g dung). Furthermore, a significant positive non-additive effect of mixing litter and dung on their total mass loss was detected for the mixture at a litter:dung ratio of 10:6, the ratio in the major grazing area of the grassland. Our findings suggest that mixture of herbivore dung with plant litter, as in actual grassland ecosystems, promotes litter decomposition, and the composition of the litter and dung in mixture, though it may inhibit dung decomposition, due to the changes in chemical stoichiometry of decomposing materials and biophysical microenvironment by the mixing. It is necessary to incorporate the non-additive effect of litter and dung mixture in modeling carbon and nutrient cycling of grassland ecosystems. [ABSTRACT FROM AUTHOR]