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Closely related species often conserve similar niches despite interacting negatively. We suggest that close relatives may interact positively via ecosystem feedbacks: leaf litter produced or exposed in a closely related neighbourhood (low phylogenetic isolation) may decompose more quickly, leading to more rapid nutrient recycling. We studied decomposition of leaf litter of oaks Quercus petraea across 8 and 14 months, reciprocally transplanting leaf litters between low and high phylogenetic isolation to distinguish between effects mediated by leaf litter quality and by decomposition environment. We found that, by affecting litter quality, phylogenetic isolation reduced decomposition across 14 months (loss of litter mass and C). Moreover, by affecting litter quality and decomposition environment, phylogenetic isolation reduced microbial biomass and extensively altered relationships between C and N losses and abundances/diversities of different soil organisms across 8 and 14 months. Phylogenetic isolation was to a large extant driven by percentage of gymnosperms, explaining the decomposition‐environment mediated effects. Such environment‐mediated effects reflected decreasing soil humidity and pH with phylogenetic isolation, while litter‐quality mediated effects reflected decreasing leaf phytophagy or increasing leaf phenolics. Tree‐species richness, in contrast, did not explain effects of phylogenetic isolation, and had little effect overall. To conclude, coexistence of oaks with distant relatives partly impedes recycling of leaf litter and re‐organizes the trajectories of this recycling. In contrast, oaks coexisting with close relatives may profit from a positive ecosystem feedback through increased nutrient recycling, possibly contributing to the conservation of the oak's niches. We suggest that such a positive ecosystem feedback among close relatives might exist in other late successional tree species. [ABSTRACT FROM AUTHOR]

Indicators of variations in soil carbon stock of coniferous–broadleaf forest are of high predictive value. This article provides an assessment of the contribution of environmental factors to the variation of carbon stock in forest soils. The study was performed in the Bryansk Forest Reserve on 45 test plots located in different landscapes. Five groups of factors, characterizing vegetation, macrofauna, landscape, topography, and history of management, were analyzed. Statistical relationships between the parameters of carbon stock and environmental factors were assessed, using machine learning methods. The quality of litter formed by dominants of tree, herbaceous, and of the moss layers is the main factor, determining the carbon stock in it. Position in the landscape and the topographic characteristics are less informative. The carbon stock of the OL litter subhorizon is the highest in forests with a great proportion of pine. The mosses cover is the most informative indicator of variation in carbon stock in the OFH litter subhorizon. The results of regression analysis of carbon stock in the A horizon and in the upper 30-cm-thick layer reflect a significant contribution of parameters of increased hydromorphism, as well as of characteristics of functional organization of forest ecosystems, the ecological-cenotic structure of plant communities (the proportion of nemoral species in the undergrowth and shrub layers), and the functional diversity of earthworms. [ABSTRACT FROM AUTHOR]

Background and aims: The decomposition of shoot and root litter has been extensively studied in natural ecosystems. Our understanding of the decomposition of plant litter including carbon (C) and nitrogen (N) release from root residues is still limited in intercropping. We addressed how C and N release from straw and root decomposition might be affected in maize/legume intercrops. Methods: A decomposition experiment was conducted within a field experiment including two N rates (i.e. no-N and N-addition), three monocultures (maize, soybean, and peanut), and two intercrops (maize/soybean and maize/peanut). Following five retrievals of polyethylene litterbag in 341 days, we assessed the C and N loss (i.e. release) and the mixing effects of both straw and root residues. Results: Straws released 38.32% more C and 43.59% more N than root residues across all crop species. Maize/peanut residues showed faster C and N release than maize/soybean residues. The release of C and N was asynchronous in both straw and root decomposition in maize/peanut intercropping. Straw mixtures of maize and legume released C faster than expected from monoculture straw. Litter functional (i.e. initial chemical traits) dissimilarity between maize and legume accelerated C and N release from the decomposition of straw, but not root, in maize/legume intercropping. Conclusions: These results suggest that C and N release from maize/legume residues can be explained by both residue quality and litter functional dissimilarity. Our findings have important implications for the management of straw and root residues to reduce reliance on chemical fertilizers in intercropping. [ABSTRACT FROM AUTHOR]

The impact of plant litter on soil carbon (C) cycling is influenced by external nitrogen (N) deposition and plant litter chemistry. While previous research has mainly focused on inorganic N deposition and its effect on plant litter decomposition and soil C cycling, the influence of organic N remains poorly understood. In this study, we conducted a 180-day incubation experiment to investigate how different N forms (NH4NO3, Urea 50% + Glycine 50%) and litter chemistry (varying lignin/N ratios) affect CO2 emissions from an acidic Moso bamboo (Phyllostachys edulis) forest soil. Our findings indicate that litter addition increased soil CO2 emissions and the proportion of CO2-C to Total C (considering added litter-C as a part of total C). Specifically, Moso bamboo leaf litter with a lower lignin/N ratio led to higher soil CO2 emissions and CO2-C/Total C ratios. The combined addition of litter and N exhibited an antagonistic effect on soil CO2 emissions, with inorganic N having a more pronounced effect compared to organic N. This antagonistic effect was attributed to the N addition-induced soil acidification, thereby inhibiting microbial activities and reducing soil respiration promoted by litter input. This effect was confirmed by random forest analysis and partial least squares path modeling, which further identified soil dissolved organic C and pH as critical factors positively influencing soil CO2 emissions. Overall, our study suggests that atmospheric N deposition can mitigate litter-induced soil CO2 emissions, particularly under inorganic N forms and when leaf litters with high lignin/N ratios are introduced. [ABSTRACT FROM AUTHOR]

Soil fertility is often evaluated under various forest land cover types to determine the capacity of each area to support plant productivity. Therefore, this study aimed to (1) assess the current soil fertility status of six land cover types in the Alas Bromo educational forest of Universitas Sebelas Maret using the Soil Fertility Index method and (2) identify the factors influencing the status. The six different land cover types investigated in this descriptive-exploratory study using a survey method included (1) pine, (2) pine-mahogany, (3) mahogany, (4) mixed trees, (5) annual crops, and (6) pine replanting, with four repetitions. Furthermore, the composite soil sample represented each repetitive area, and the assessment results showed that the soil fertility status was categorized as low to moderate. The categorization order was mahogany>mixed trees>pine replanting>annual crops>pine>pine-mahogany which had fertility indices of 0.57, 0.56, 0.53, 0.51, 0.49, and 0.45, respectively. Soil fertility determinants across the six land cover types comprised litterfall, breast height diameter, and tree density. Future investigations should evaluate the relationship between litter quality, soil biota, and decomposition rate with fertility to identify the appropriate strategy for fertility enhancement on each land cover.

This study aimed to evaluate the effects of floor position in a multitier closed house on microcli-matic air quality and litter conditions. Fourteen thousand and five hundred unsexed Ross broiler chick-ens with a DOC body weight of 45.84 ± 2.40 g were placed on each floor of a three-tier closed house and allocated to a randomized block design consisted of 3 treatments and 18 replications. Each floor measured 12x78x2 m3. The maintenance procedure was applied according to the integrated partnership company guidelines PT Tumbuh Optimal Prima, with an observation period of 28 days. The treatments applied were as follows: T1= placement of broiler chickens on the 1st floor, T2= placement of broiler chickens on the 2nd floor, and T3= placement of broiler chickens on the 3rd floor. Microclimate condi-tions (temperature, RH, wind speed, temperature humidity index, wind chill effect, and calculated real feel temperature) and air quality parameters (NH3, CO2, O2, TVOC, and HCHO) were measured daily on each floor. Litter conditions, included water content, litter temperature, NH3 content, pH, and caking were measured weekly. The results revealed that during the starter phase (weeks 1–2), the microclimat-ic conditions and air quality of the 3rd floor were significantly better (P0.05). In conclusion, the microclimatic conditions and air quali-ty of the 3rd floor were generally superior to those of the lower floors over the 4-week rearing period, whereas the litter quality was inferior.

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]

The variation within and across species has afterlife effects on carbon and nutrient cycling through the alteration of litter decomposability. However, the focus on leaves may not reflect a whole-plant economic spectrum of strategies. Here, we assessed the patterns and predictors of flower and leaf-litter decomposition at the intra- (i.e., flowers and leaves of the same species) and inter-specific (i.e., flowers and leaves from different species) levels for 29 tropical woody species in northeast Brazil. We evaluated nine functional litter traits, including structural and chemical traits. Flower litter decomposed, on average, three times faster than leaf litter (11.9% and 39.4% mass remaining, respectively) and exhibited higher water-holding capacity (WHC), leaching (LEA), and N, P, and K content. Otherwise, leaf litter showed higher density (DEN) and Ca, Mg, and Na content. The average relative differences in decomposition rate and functional traits between flower and leaf litter did not differ at both intra- and inter-specific levels. The predictors of decomposition were mostly similar, explaining 39% and 37% of flower and leaf litter, respectively. Leaching, P, Ca, Mg, and Na predict both flower and leaf-litter decomposition. However, WHC exclusively predicted flower-litter decomposition, and DEN, N, and K exclusively predicted leaf-litter decomposition. The observed differences in decomposition rate and functional traits between flower and leaf litter indicate that the afterlife effects differ between these plant organs and leverage the role of flower litter and its secondary consequences to nutrient and carbon cycling on ecosystems. [ABSTRACT FROM AUTHOR]

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]

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 aimed to evaluate the effects of floor position in a multitier closed house on microclimatic air quality and litter conditions. Fourteen thousand and five hundred unsexed Ross broiler chickens with a DOC body weight of 45.84 ± 2.40 g were placed on each floor of a three-tier closed house and allocated to a randomized block design consisted of 3 treatments and 18 replications. Each floor measured 12x78x2 m³. The maintenance procedure was applied according to the integrated partnership company guidelines PT Tumbuh Optimal Prima, with an observation period of 28 days. The treatments applied were as follows: T1= placement of broiler chickens on the 1st floor, T2= placement of broiler chickens on the 2nd floor, and T3= placement of broiler chickens on the 3rd floor. Microclimate conditions (temperature, RH, wind speed, temperature humidity index, wind chill effect, and calculated real feel temperature) and air quality parameters (NH3, CO2, O2, TVOC, and HCHO) were measured daily on each floor. Litter conditions, included water content, litter temperature, NH3 content, pH, and caking were measured weekly. The results revealed that during the starter phase (weeks 1–2), the microclimatic conditions and air quality of the 3rd floor were significantly better (P<0.05) than those of the 1st floor and 2nd floor, a trend was continued during weeks 3–4. Notably, the results obtained on the 1st and 2nd floors were still within the normal range for the broiler thermoneutral zone. Conversely, the 3rd floor litter was generally poorer, with significantly higher (P<0.05) moisture content, temperature, and caking than the lower floors, particularly in weeks 3–4. However, broiler placement on different floors did not significantly affect the litter pH (P>0.05). In conclusion, the microclimatic conditions and air quality of the 3rd floor were generally superior to those of the lower floors over the 4-week rearing period, whereas the litter quality was inferior. [ABSTRACT FROM AUTHOR]

We previously reported that high levels (≥50%) of black soldier fly larvae meal (BSFLM) reduced growth and altered organs morphology in broiler chickens. Herein we further examined gastrointestinal, breast, bone, plasma, and litter attributes in broiler chickens fed partial to complete replacement of soybean meal (SBM) with BSFLM. A total of 1152 day-old Ross × Ross 708 male chicks (n = 8) were allocated to 48 pens and assigned one of six diets: a basal corn-SBM diet (0BSFLM), four diets in which SBM in 0BSFLM was replaced with BSFLM at 12.5%, 25%, 50%, and 100% (12.5BSFLM, 25BSFLM, 50BSFLM, and 100BSFLM) and a final diet (0 + AGP) in which 0BSFLM was fed with coccidiostat and antibiotic. Birds were bled for plasma and necropsied for samples. Litter samples were collected on days 45 to 47. Breast weight, woody breast, and hardness scores and tibia morphometry reduced linearly in response to BSFLM inclusion (P < 0.001). BSFLM linearly increased plasma Lys, Met, Thr, uric acid, creatine kinase and decreased Arg and potassium (P < 0.05). Litter ammonium nitrogen and potassium decreased linearly in response to BSFLM (P < 0.001). In conclusion, the data suggested physiological and metabolic inefficiencies in broiler chickens fed isocaloric and isonitrogenous diets with ≥50% BSFLM replacement of SBM. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigated the effects of perch provision on the productivity and welfare of broilers in two commercial farms. Broiler houses from each farm were provided with or without perches. The results showed that perches did not consistently affect productivity measures such as weight or uniformity. However, corticosterone levels, as the stress indicator, were lower in the group with perches. While there were no significant differences in some animal welfare indicators, gait scores were affected by perches in one of the farms employed. In conclusion, perches did not significantly improve broiler productivity or welfare, but they did have a positive effect on reducing stress. These findings provide important insights for improving broiler farming environments. This study explored the impact of perches on the productivity and welfare of broilers raised on two animal welfare-certified farms (designated as Farm A and B) in South Korea. Broiler houses in each farm were provided with or without wooden square-shaped perches (2 × 2 cm) at a rate of 2 m per 1000 birds. The study aimed to assess whether perches could influence productivity measures, such as weight and uniformity, and animal welfare indicators, including corticosterone levels and physical health markers. The findings showed that the effects on productivity were inconsistent, varying by farm and period. Corticosterone levels, as an indicator of stress, were significantly lower in the perch group on farm B, but not on farm A. There were no significant differences in welfare indicators such as footpad dermatitis or feather cleanliness, although gait scores improved in farm B with perch provision. Litter moisture was higher in the perch group of farm A, but showed no difference in farm B. The study concluded that while perches did not consistently improve productivity or welfare, they did help reduce stress in broilers, as indicated by lower corticosterone levels. [ABSTRACT FROM AUTHOR]

Litterfall, decomposition, and nutrient release to the soil are important biogeochemical cycling processes in agroecosystems. The objective of this study was to evaluate the patterns of decomposition and nutrient release of the leaves of four tree legumes with agroforestry potential: Piscidia piscipula, Gliricidia sepium, Leucaena leucocephala, and Lysiloma latisiliquum, common in the areas with natural regeneration after the abandonment of agriculture in south-eastern Mexico. We employed 112 litterbags with 40 g of dry leaf litter on ground surface for decomposition and recollected seven bags per species at 30, 60, 90, and 120 days. The initial and recollected samples were oven-dried, and weighed to determine the remaining dry mass (DM), organic matter (OM), carbon (C), nitrogen (N) content, and the C:N ratio. The initial OM and N contents of L. leucocephala leaves were greater, compared to the rest of the legumes. P. piscidia and G. sepium showed the highest C content. P. piscidia, G. sepium, and L. latisiliquum had the highest C:N ratio, compared to L. leucocephala. The relative decomposition rate k values of DM, OM, C, and N were greater for L. leucocephala. The remaining DM, OM, C, and N were affected by the interaction between species and decomposition time. G. sepium and L. latisiliquum showed greater remaining mass from 30 to 60 days of decomposition. However, after 60 days L. latisiliquum showed the greatest remaining DM and OM until the end of the incubation period (120 days). We conclude that L. leucocephala had the highest rate of decomposition and the fastest release of nitrogen, however, the asynchronous pattern of litter decomposition among the tree legumes showed the potential to supply OM and nutrients to the soil for a prolonged period if planted in combination in agroforestry systems. [ABSTRACT FROM AUTHOR]

There are differences in the litter quality and decomposition rate of kiwifruit varieties, but it is not clear whether these differences are related to microbial communities. The leaf litters of two kiwifruit varieties (A. chinensis cv 'Hongyang' and A. chinensis cv 'Jinyan') were taken as objects, and the structure, diversity, and succession of the soil microbial communities were analyzed using an in situ decomposition experiment. Moreover, the contents of C, N, P, and K in the litters during decomposition were analyzed. The results show that there were variety differences in community structure at the generic level. Lophotrichus, Acaulium, and Fusarium were relatively more abundant in the microbial community of the 'Hongyang' kiwifruit litter, and Humicola and Tausonia were relatively more abundant in the microbial community of the 'Jinyan' kiwifruit litter. Subgroup_6 and Sphingomonas were the dominant bacteria. The bacterial community diversity of 'Jinyan' kiwifruit was higher than that of the 'Hongyang' kiwifruit litter. The community diversity was higher in the middle and later periods. The contents of C and N in the litters were the main factors affecting microbial communities. The abundances of Humicola and Apiotrichum were negatively correlated with the contents of C and N, and the abundances of Sphingomonas and SC-I-84 were positively correlated with the content of C. There were variety differences in the microbial communities corresponding to the decomposition processes of the 'Hongyang' and 'Jinyan' kiwifruit litters. The mechanisms of the variety differences were related to litter quality and the initial soil microbial community. [ABSTRACT FROM AUTHOR]

With global warming, understanding the effect of elevated temperature on the decomposition of Chinese fir needle litter has significant implications for nutrient cycling, yield, and management of economically important Chinese fir plantations. We conducted simulated warming decomposition experiments in incubators at 25 °C, 30 °C, and 35 °C on Chinese fir needle litter from middle-aged, mature, and overmature stands. Changes in litter mass and concentrations of some metallic elements and recalcitrant components were measured in litter sampled at different decomposition time-steps up to 264 days (d). Warming to 35 °C significantly increased the mass loss rate of needle litter from overmature stands throughout the experiment (except at 72 d). The effect of warming on litter mass loss rate for middle-aged and mature stands was lower and is attributed to higher litter quality in these stands. Compared to 25 °C, warming to 30 °C and 35 °C increased the needle litter decomposition rate across all developmental stages by 17.3% and 48.3%, respectively. Potassium (K), calcium (Ca), and magnesium (Mg) were mostly released during needle litter decomposition in all Chinese fir developmental stages. Lignin, condensed tannins, total phenols, and cellulose were enriched in needle litter, while the release of hemicellulose from near the start of the decomposition experiment was attributed to its lower molecular weight compared with other carbohydrates in litter. Compared with 25 °C, warming to 35 °C increased the release rates from litter of K, Ca, and Mg by 14.7%, 24.6%, and 21.5%, and the release rates of lignin, total phenols, cellulose, and hemicellulose by 7.5%, 8.8%, 10.4%, and 13.7%. Needle litter iron (Fe), aluminum (Al), and sodium (Na) in different development stages and manganese (Mn) in the overmature stands were mostly enriched during the experiment. Warming significantly promoted the enrichment of Fe, Al (except for mature stands), and Na, and reduced the enrichment of Mn. In summary, the sensitivity of needle litter to temperature in overmature stands is higher than that in middle-aged and mature stands, suggesting that forest managers can extend the rotation length of Chinese fir plantations to increase the yield of large-diameter timber, litter decomposition, and ecosystem nutrient return. [ABSTRACT FROM AUTHOR]

1. This study evaluated the validity, inter-assessor reliability and intra-assessor repeatability of three visual scoring systems for litter quality, one known as the Welfare Quality Assessment Protocol© and two complementary systems for friability and humidity developed by the ClassyFarm initiative.2. In 6 rooms of an experimental barn, 2450 medium-growing broiler chickens were reared on coarse sawdust litter until they reached a body weight of 2.2 kg at 43 days of age, with a stocking density of 33 kg/m2.3. Sixty-six litter samples were analysed for litter moisture at two different time points during the broiler chickens’ production cycle, and were visually scored using the three systems, two consecutive times, by 7 assessors to analyse their validity, inter-reliability and intra-repeatability according to the litter moisture level.4. The three resulting scores were correlated with the litter moisture (p < 0.001) and correlations were stronger when the litter moisture was above 35%. Similarly, inter-assessor reliability and intra-assessor repeatability were better for all three scoring systems when litter moisture was above 35% than when it was below 35%.5. The ClassyFarm Friability system was the most reliable regardless of litter moisture level. The ClassyFarm Humidity system was the least reliable and repeatable when the litter moisture was below 35%. The Welfare Quality scoring system lay between the two ClassyFarm systems considering inter-assessor reliability, but was as repeatable as the ClassyFarm Friability system. [ABSTRACT FROM AUTHOR]

Background and aims: Plant litter decomposition is a crucial pathway of the global carbon (C) cycle, and controls the net primary productivity in terrestrial ecosystems. Our understanding of litter decomposition is primarily based on decay patterns observed for leaf litter tissues. The distal shoot systems (leaves and the first few orders of twigs) vary vastly in function and tissue chemistry and both decomposition patterns and controlling factors of these multi-type litter complexes are poorly understood. Methods: We followed decomposition of leaf litter and the first three orders of twigs across 10 temperate tree species over 2 years in Northeast China. Results: Eight species showed slower decomposition rates in twigs than leaf litter, and almost all species showed that decomposition rates decrease from first- to third-order twigs. The decomposition of twigs and leaf litter in 10 tree species were not coordinated. Most importantly, in contrast to leaf litter, the variation in twigs decomposition cannot be predicted by the commonly used parameters like N contents, but is predicted by initial concentrations of Mg and cellulose plus lignin/P ratio in twig tissues. Conclusions: We conclude that there were significant differences in decomposition rates among the tree distal shoot systems. Leaf litter decomposition does not mirror twigs decomposition, and variation in their decomposition rates was driven by two different subset of litter traits, at least in the ten species we studied. Additionally, the heterogeneity within the tree distal shoot systems could lead to differences in their contribution to soil in term of carbon dynamics. [ABSTRACT FROM AUTHOR]

ABSTRACT Photodegradation—photochemical mineralization of standing litters—often exerts a legacy effect aiding biodegradation in soil (PLE), which is overlooked in deciduous forests containing marcescent leaves. Meanwhile, increasing anthropogenic microplastics have deposited in forests, how they would affect the PLE on subsequent litter bio‐decomposition is currently unknown. Here, we employed an ultraviolet‐accelerated aging chamber to replicate the abiotic photodegradation process of a naturally marcescent tree, Lindera glauca, then manipulated mesocosm bio‐incubations to quantify how decomposers (microbial alone or with soil animals) and microplastic contamination would interactively affect the PLE. We found abiotic photodegradation significantly decreased litter lignin content before and after the bio‐incubation. During an early phase decomposition, lignin lost greatly and displayed a crucial role in determining the ways that soil animal and photodegradation affect the bio‐decomposition. Microbial decomposer alone led to a positive PLE universally. Soil animals depressed microbial biomass and inhibited the microbial‐mediated PLE in unpolluted mesocosms but intensified the PLE in contaminated soils. We conclude that decomposer interactions can attenuate PLE, but microplastics will disrupt the established equilibrium, making contaminated soil more susceptible to photodegradation‐induced litter chemical changes. This promotes integration of radiation and emerging pollution to further our understanding of biogeochemical cycle in forest ecology.

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]

There are differences in the litter quality and decomposition rate of kiwifruit varieties, but it is not clear whether these differences are related to microbial communities. The leaf litters of two kiwifruit varieties (A. chinensis cv ‘Hongyang’ and A. chinensis cv ‘Jinyan’) were taken as objects, and the structure, diversity, and succession of the soil microbial communities were analyzed using an in situ decomposition experiment. Moreover, the contents of C, N, P, and K in the litters during decomposition were analyzed. The results show that there were variety differences in community structure at the generic level. Lophotrichus, Acaulium, and Fusarium were relatively more abundant in the microbial community of the ‘Hongyang’ kiwifruit litter, and Humicola and Tausonia were relatively more abundant in the microbial community of the ‘Jinyan’ kiwifruit litter. Subgroup_6 and Sphingomonas were the dominant bacteria. The bacterial community diversity of ‘Jinyan’ kiwifruit was higher than that of the ‘Hongyang’ kiwifruit litter. The community diversity was higher in the middle and later periods. The contents of C and N in the litters were the main factors affecting microbial communities. The abundances of Humicola and Apiotrichum were negatively correlated with the contents of C and N, and the abundances of Sphingomonas and SC-I-84 were positively correlated with the content of C. There were variety differences in the microbial communities corresponding to the decomposition processes of the ‘Hongyang’ and ‘Jinyan’ kiwifruit litters. The mechanisms of the variety differences were related to litter quality and the initial soil microbial community.

This study explored the impact of perches on the productivity and welfare of broilers raised on two animal welfare-certified farms (designated as Farm A and B) in South Korea. Broiler houses in each farm were provided with or without wooden square-shaped perches (2 × 2 cm) at a rate of 2 m per 1000 birds. The study aimed to assess whether perches could influence productivity measures, such as weight and uniformity, and animal welfare indicators, including corticosterone levels and physical health markers. The findings showed that the effects on productivity were inconsistent, varying by farm and period. Corticosterone levels, as an indicator of stress, were significantly lower in the perch group on farm B, but not on farm A. There were no significant differences in welfare indicators such as footpad dermatitis or feather cleanliness, although gait scores improved in farm B with perch provision. Litter moisture was higher in the perch group of farm A, but showed no difference in farm B. The study concluded that while perches did not consistently improve productivity or welfare, they did help reduce stress in broilers, as indicated by lower corticosterone levels.

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.

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.

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]

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]

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]

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]

Although the litter deposition and decomposition dynamics of the Pinus genus is relatively well known, the effects of the mixture of needles from different species and the influence of the microenvironmental condition of the forest system have rarely been investigated. The objective of this work was to evaluate the decomposition of needles of two Pinus species (Pinus caribaea and Pinus oocarpa) and the needle-mixing of these species when exposed to a planted forest condition (one pure and one mixed of these two species) and a natural tropical forest condition. Senescent needles were collected from the base of the treetops. Next, 10 g samples of the dry needles were placed in litterbags: for the pure plantation, 100% samples of P. caribaea were used, while the samples for the mixed plantation were composed of 50% P. caribaea +50% P. oocarpa. The litterbags were placed in the planted forest environment and in the natural forest environment. Litterbag collections were performed after 60, 120, 180, 240, 300 and 360 days after installation. The dry needle material (before and after decomposition) was chemically characterized. The litter composition and the microenvironment influenced the decomposition dynamics. The decomposition rate of mixed needle litter was higher than the rate of pure litter, being even more expressive when in the native forest condition. [ABSTRACT FROM AUTHOR]

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]

The estimation of leaf litter turnover is often limited to early-stage decomposition using unrepresentative models and litter types. In tropical secondary forests, particularly exotic-dominated novel forests, the characterisation of litter turnover remains poor. This study estimated the annual turnover of in-situ leaf litter across four forest successional types in Singapore using a Weibull residence time model. Litter turnover and nutrient dynamics diverged between young secondary and old-growth forests. In particular, within novel forests, annual phosphorus return via leaf litterfall was three times that of primary forests, while the mass loss of in-situ leaf litter was highest among all forest successional types, estimated at 92.8% annually with a mean residence time of 176 days, resulting in a litter pool size a third that of primary forests. Our findings suggest that tree species composition and species-specific effects shaped the observed variations in litter turnover and nutrient dynamics across forest successional types and forest stands, whereas tree species richness, canopy structure, soil nutrient levels, and microclimate were found to be non-predictors. Taken together, our study provides an insight into litter turnover in human-modified tropical landscapes increasingly characterised by novel forests, potentially leading to a reduction in surface litter and soil organic carbon pools. [ABSTRACT FROM AUTHOR]