Litter Decomposition Processes Research Articles

Effects on Biomass of Cubaris murina Brandt (Crustacea: Isopoda) Exposed to Soil Contaminated With Glyphosate in Laboratory Studies

Terrestrial isopods play an important role in the cycling of nutrients, contributing to the first processes of litter decomposition. In this work, organisms of Cubaris murina from laboratory cultures were used in ecotoxicity tests, to assess their sensibility to glyphosate how it affects their biomass. The contaminant solutions were prepared by herbicide Roundup®. The initial nominal concentrations were 4.8, 9.6, 14.4 and 19.2 mg glyphosate/g soil. Ten offspring of 2 to 4 days old were exposed in each treatment and in one control. All the treatments, in quadruplicate, received regularly sprays of distilled water. After five weeks, the isopods were weighed, and the mean weight of the isopods of each treatment was compared to the control, using ANOVA. Significant differences in relation to control (p < 0.001) were encountered on 14.4 and 19.2 mg gli/g soil in two repetitions of the experiment. Effects on biomass showed more sensibility than 7-d-LC50 of glyphosate to C. murina (35.5 mg gli/g soil).

The freezer defrosting: global warming and litter decomposition rates in cold biomes

Summary Decomposition of plant litter, a key component of the global carbon budget, is hierarchically controlled by the triad: climate > litter quality > soil organisms. Given the sensitivity of decomposition to temperature, especially in cold biomes, it has been hypothesized that global warming will lead to increased litter decomposition rates, both through direct temperature effects and through indirect effects on litter quality and soil organisms. A meta‐analysis of experimental warming studies in cold biomes (34 site‐species combinations) showed that warming resulted in slightly increased decomposition rates. However, this response was strongly dependent on the method used: open top chambers reduced decomposition rates, whereas heating lamps stimulated decomposition rates. The low responsiveness was mainly due to moisture‐limited decomposition rates in the warming treatments, especially at mesic and xeric sites. This control of litter decomposition by both temperature and moisture was corroborated by natural gradient studies. Interspecific differences in litter quality and decomposability are substantially larger than warming‐induced phenotypic responses. Thus, the changes in the species composition and structure of plant communities that have been observed in medium‐term warming studies in cold biomes will have a considerably greater impact on ecosystem litter decomposition than phenotypic responses. Soil fauna communities in cold biomes are responsive to climate warming. Moreover, temperature‐driven migration of the, hitherto absent, large comminuters to high‐latitude sites may significantly increase decomposition rates. However, we do not know how far‐reaching the consequences of changes in the species composition and structure of the soil community are for litter decomposition, as there is a lack of data on functional species redundancy and the species’ dispersal ability. Global warming will lead to increased litter decomposition rates only if there is sufficient soil moisture. Hence, climate scenario and experimental studies should focus more on both factors and their interaction. As interspecific differences in potential decomposability and litter chemistry are substantially larger than phenotypic responses to warming, the focus of future research should be on the former. In addition, more light should be shed on the below‐ground ‘darkness’ to evaluate the ecological significance of warming‐induced soil fauna community changes for litter decomposition processes in cold biomes.

Comparison of Leaf Litter Decomposition Rates in Restored and Mature Riparian Forests on the Sacramento River, California

Abstract One of the largest riparian restoration projects in the United States is currently taking place in California on the Sacramento River. Nearly 2,000 ha of land adjacent to the river channel have been revegetated with native riparian species in an effort to reestablish riparian forests. The objective of this study was to compare leaf litter decomposition rates in restored riparian forests to those in mature, naturally established riparian forests, in order to monitor the development of this ecosystem function in restored forests. Leaf litter decomposition rates were measured over 1 year in six restored riparian forests (4, 7, and 9 years old) and two mature remnant riparian forests (>50 years old), in order to test two hypotheses: (1) decomposition rates of restored and mature forests are significantly different and (2) decomposition rates in the chronosequence of restored forests are moving along a trajectory, approaching the decomposition rates characteristic of mature forests as they age. Statistical analyses revealed no significant differences in annual decay rates among the four different forest ages and no trajectory among leaf litter decomposition rates in restored forests. These results suggest that a functionally equivalent process of leaf litter decomposition occurs in both restored and naturally established forests and show promise for the efficiency of nutrient cycling processes in these restored forests.

Involvement of Lignocellulolytic Enzymes in the Decomposition of Leaf Litter in a Subtropical Forest

The involvement of ligninolytic and cellulolytic enzymes, such as laccase, lignin peroxidase, manganese peroxidase, carboxymethylcellulase (CMCase), and filter paper activity (FPA), in the decomposition process of leaf litter driven by 6 soil-inhabiting fungi imperfecti was studied under solid-state fermentations. All the tested fungi exhibited varied production profiles of lignocellulolytic enzymes and each caused different losses in total organic matter (TOM) during decomposition. Based on the results, the 6 fungi could be divided into 2 functional groups: Group 1 includes Alternaria sp., Penicillium sp., Acremonium sp., and Trichoderma sp., and Group 2 includes Pestalotiopsis sp. and Aspergillus fumigatus. Group 1, with higher CMCase and FPA activities, showed a higher decomposition rate than the fungi of Group 2 over the first 16 d, and thereafter the cellulolytic activities and decomposition rate slowed down. Group 2 showed the maximum and significantly higher CMCase and FPA activities than those of the Group 1 fungi during the later days. This, combined with the much higher laccase activity, produced a synergistic reaction that led to a much faster average mass loss rate. These results suggest that the fungi of Group 1 are efficient decomposers of cellulose and that the fungi of Group 2 are efficient decomposers of lignocellulose. During cultivation, Pestalotiopsis sp. produced an appreciable amount of laccase activity (0.56+/-0.09 U/ml) without the addition of inducers and caused a loss in TOM of 38.2%+/-3.0%, suggesting that it has high potential to be a new efficient laccase-producing fungus.

Effects on Biomass of Cubaris murina Brandt (Crustacea: Isopoda) Exposed to Soil Contaminated With Glyphosate in Laboratory Studies

Terrestrial isopods play an important role in the cycling of nutrients, contributing to the first processes of litter decomposition. In this work, organisms of Cubaris murina from laboratory cultures were used in ecotoxicity tests, to assess their sensibility to glyphosate how it affects their biomass. The contaminant solutions were prepared by herbicide Roundup®. The initial nominal concentrations were 4.8, 9.6, 14.4 and 19.2 mg glyphosate/g soil. Ten offspring of 2 to 4 days old were exposed in each treatment and in one control. All the treatments, in quadruplicate, received regularly sprays of distilled water. After five weeks, the isopods were weighed, and the mean weight of the isopods of each treatment was compared to the control, using ANOVA. Significant differences in relation to control (p < 0.001) were encountered on 14.4 and 19.2 mg gli/g soil in two repetitions of the experiment. Effects on biomass showed more sensibility than 7-d-LC50 of glyphosate to C. murina (35.5 mg gli/g soil).

The Analysis of Collembolan Species' Abundance Distribution in Beech and Spruce Forests Habitats in Jastrebac Mountain (Serbia)

ABSTRACTCollembola were sampled over a period of five consecutive years in beech and spruce forest on mountain Jastrebac (Serbia). The two identified Collembola communities were thought to respond to resource dynamics represented by litter supply and decomposition processes. The collembolan communities were dominated by two species: Folsomia quadrioculata and F. penicula. In both habitats phenological changes occur by a decrease in abundance of the dominant species followed by an increase in the abundance of accessory species. In the beech stands a large decrease in abundance of the dominant species with a moderate replacement was noted, whereas species replacement is greater relative to the decrease in abundance of the dominant species in spruce. In the analysis of community structure the ranked abundance curves were compared with corresponding theoretical curves of several S/N distributions, in order to identify the underlying models of community structure. The analysis of species' abundance curves showed a marked difference in summer compared to the spring and autumn periods. Comparing the observed distributions with different S/N models the “niche preemption” model and MacArthur's “broken stick” model were found to explain adequately the observed distributions.

Effects of environmental factors and leaf chemistry on leaf litter colonization by fungi in a Mediterranean shrubland

Estimation of litter colonization by fungi, using ergosterol, an indicator of fungal biomass, is a reliable way to describe the process of leaf litter decomposition. This litter colonization by fungi is regulated both by exogenous or environmental factors, and endogenous factors, i.e. litter chemistry. In this work, we have examined the effects of some of these factors on litter fungal colonization in a Mediterranean ecosystem, by determining ergosterol content of Quercus coccifera leaf litter. Environmental factors have been studied through the fertility of the soil, by comparing plots amended with two rates of compost and plots without amendment. Results indicated that (i) compost had a significant effect on soil fertility but did not increase ergosterol content of leaf litter and (ii) soil humidity improved leaf litter colonization by fungi. Endogenous factors have been studied through measurements of total phenolic and ergosterol concentrations of seven shrub species leaf litter. We have shown (i) a negative significant correlation between total phenolic compounds and ergosterol concentrations of leaf litter and (ii) a positive significant correlation between total phenolic compound concentrations in green leaves and in leaf litter. We conclude that, in this Mediterranean shrub ecosystem, leaf litter colonization by fungi is controlled by soil moisture and plant leaf litter quality.

Food web properties in aquatic microcosms with litter mixtures are predictable from component species

Many aquatic systems depend on allochthonous organic matter. Quality of litter differs between plant species. Therefore, the composition of the surrounding veg- etation may influence litter decomposition and other processes in aquatic food webs. We recorded the abundance of insect larvae, as well as the diversity of cultivable fungi and bacteria, the metabolic diversity of the microflora, and leaf litter decomposition rates in aquatic outdoor microcosms, using litter from four broad-leaved tree species and a mixture of the four litter types. Diversity of fungi, abundance of bacteria and functional diversity of the microflora and decomposition differed between microcosms with litter from each of the four tree species. For microcosms with the mixture of litter, observed values of all measured variables did not differ from the expectations derived from microcosms with litter from only one tree species. We conclude that specific traits of the component litter species (e. g. C/N ratio) outweigh possible non-additive effects in mixtures. Our results contrast with findings in terrestrial systems where de- composition rates of mixtures are not always predictable from the rates measured for the component species.

Seasonal variation in CO2 production of leaf litter from different deciduous forests at the early decomposition stage

We collected leaf litter from a deciduous broadleaf forest and a larch forest in Hokkaido, Japan naturally without using litter traps or litter bags. The litter collection was conducted every month from October 2001 through October 2002 except in the snowy season. We measured the CO2 production rate of the litter samples through microbial respiration using the chamber method in a laboratory under different temperature and moisture conditions to investigate the seasonal pattern and temperature and moisture responses of CO2 production at the early stage of litter decomposition. Seasonal variation was found in the CO2 production rate per unit of litter dry weight (Pdw), or the litter decomposition rate, for both broadleaf and larch litters. Although seasonal patterns differed somewhat according to temperatures and species, Pdw reached the minimum in June. The moisture sensitivity of Pdw decreased with time and reached the minimum in summer for both broadleaf and larch litters, whereas the seasonal pattern of the temperature sensitivity (Q10) was not clear. The seasonal pattern of Pdw was explained by its C:N ratio for broadleaf litter. For larch litter, however, the relationship between Pdw and the C:N ratio was complicated because of fresh litterfall supplied gradually before defoliation. The temperature and moisture sensitivities of Pdw changed in parallel with the C:N ratio for both broadleaf and larch litters, respectively. These facts suggest the importance of litter chemical quality in the early decomposition process of fresh litter and the validity of the C:N ratio as an index of litter quality.

Carbon sequestration following afforestation of agricultural soils: comparing oak/beech forest to short‐rotation poplar coppice combining a process and a carbon accounting model

AbstractTo compare the benefits for carbon (C) sequestration of afforestation with a multifunctional oak–beech forest vs. a poplar short‐rotation coppice (SRC), model simulations were run through a serial linkage of a mechanistic model and an accounting model. The process model SECRETS (Stand to Ecosystem CaRbon and EvapoTranspiration Simulator) was used to predict growth, C allocation and soil C. The output from SECRETS was used as an input for the C accounting model GORCAM (Graz Oak Ridge Carbon Accounting Model) yielding data on C sequestration in wood products, substitution of wood fuel for fossil fuel and total CO2 emission reduction. Such C accounting based on a process model enables a more realistic calculation of forest growth, litter decomposition and soil processes. Moreover, it allows simulating the influence of climate change on the C budget.Net primary production of an oak–beech forest is low, a stable 2.5 t C ha−1 yr−1 after 150 years, compared to 6.2 t C ha−1 yr−1 for a SRC plantation. But while the yield from the SRC poplar is used as fuel and thus returns quickly to the atmosphere, the yield from the oak‐beech forest is used in long‐lasting wood products. The total C pool in the mixed forest (living biomass, wood products and soil) after 150 years amounts to 324 t C ha−1 compared to 162 in the poplar coppice. However, when account is taken of the energy substitution, coppice culture reduces emissions with 24.3–29.3 t CO2 ha−1 yr−1 while the mixed forest reduces only 6.2–7.1 t CO2 ha−1 yr−1.These results demonstrate the added value of combining detailed process models with C‐accounting models to improve the predictive capacity of model simulations.

HS-SPME analysis of volatile organic compounds of coniferous needle litter

The composition of volatile emission of Scots pine (Pinus sylvestris) and spruce (Picea exelsa) litter was studied by gas chromatography-mass spectrometry (GC-MS) and samples were collected by solid-phase microextraction (SPME) method. The list of identified compounds includes over 60 organic substances of different classes. It was established that volatile emission contain not only components of essential oils of pine and spruce needles but also a large number of organic compounds which are probably secondary metabolites of litter-decomposing fungi. They include lower carbonyl compounds and alcohols as well as products of terpene dehydration and oxidation. These data show that the processes of litter decomposition are an important source of reactive organic compounds under canopy of coniferous forests.

Decomposition of secondary compounds from needle litter of Scots pine grown under elevated CO2 and O3

AbstractElevated atmospheric carbon dioxide (CO2) and ozone (O3) concentrations have both been shown to affect plant tissue quality, which in turn could affect litter decomposition and carbon (C) and nutrient cycling. In order to evaluate effects of climate change on litter chemistry, needle litter was collected from Scots pine (Pinus sylvestris L.) saplings exposed to elevated CO2 or O3 concentration and their combination over three growing seasons in open‐top chambers. The decomposition of needle litter was followed for 19 months in a pine forest. During decomposition, needle samples for secondary compound analysis were collected and the mass loss of needles was followed. Main nutrients and total phenolics were analysed from litter in the beginning and at the end of the experiment. After 19‐month decomposition, the accumulated mass loss was about 34%; however, no significant differences were found in decomposition rates of needle litter between various treatments. Concentrations of total monoterpenes were about 4%, total resin acids 21% and total phenolics 14% of the initial concentrations in litter after 19‐month decomposition. In the beginning of litter decomposition, concentrations of individual monoterpenes –α‐pinene and β‐pinene – were significantly higher in needle litter grown under elevated CO2. However, concentrations of total monoterpenes during the whole decomposition period were not significantly affected by CO2 or O3 treatments. Concentrations of some individual and total resin acids were higher in needle litter grown under elevated CO2 or O3 than under ambient air. There were no significant differences in concentrations of total phenolics as well as nitrogen (N) and the main nutrient concentrations between treatments during decomposition. High concentrations of monoterpenes and resin acids in needles might slightly delay C recycling in forest soils. It is concluded that elevated CO2 and O3 concentrations do not have remarkable impacts on litter decomposition processes in Scots pine forests.

Species control variation in litter decomposition in a pine forest exposed to elevated CO2

AbstractNet primary production and the flux of dry matter and nutrients from vegetation to soils has increased following four years of exposure to elevated CO2 in a southern pine forest in NC, USA. This has increased the demand for nutrients to support enhanced rates of NPP and altered the conditions for litter decomposition on the forest floor. We quantified the chemistry and decomposition dynamics of leaf litter produced by five of the most abundant tree species in this ecosystem during the third and fourth growing seasons under elevated CO2. The objectives of this study were to determine (i) if there were systemic or species‐specific changes in leaf litter chemistry associated with a sustained enhancement of plant growth under elevated CO2; and (ii) whether the process of litter decomposition was altered by increased inputs of energy and nutrients to the forest floor in the plots under elevated CO2. Leaf litter chemistry, including various C fractions and N concentration, was virtually unchanged by elevated CO2. With few exceptions, plant litter produced under elevated CO2 lost mass or N at the same relative rate as that produced under ambient CO2. The relationship between initial litter chemistry and decomposition was not altered by elevated CO2. The greater forest floor mass and nutrient content in the plots under elevated CO2 had no consistent or long‐term effect on litter decomposition. Thus, we found no evidence that plant and microbial processes under elevated CO2 resulted in systemic changes in mass loss or N dynamics during decomposition. In contrast to the limited effects of elevated CO2 on litter chemistry and decomposition, there were large differences among species in initial litter chemistry, mass loss and N dynamics during decomposition. If the species composition of this forest community is altered by elevated CO2, the indirect effect of a change in species composition will exert greater control over the long‐term rate of nutrient cycling than the direct effect of elevated CO2 on litter chemistry and decomposition dynamics alone.

Comparison of litter decomposing ability among diverse fungi in a cool temperate deciduous forest in Japan

The litter decomposing ability of 79 fungal isolates (41 genera, 60 species) was assessed with the pure culture decomposition test. The isolates were collected qualitatively in a cool temperate deciduous forest in Japan during a 21-mo period. Loss of original weight of sterilized litter ranged from 0.1% to 57.6%. Six isolates in the Basidiomycota caused high weight losses ranging from 15.1% to 57.6%. Fourteen isolates in Xylaria and Geniculosporium (the Xylariaceae and its anamorph) also caused high weight losses ranging from 4.0% to 14.4%. Other isolates in the Ascomycota and associated anamorphs and in the Zygomycota caused low weight losses on mean. Six fungi in the Basidiomycota, and all in the Xylariaceae showed a bleaching activity of the litter and caused lignin and carbohydrate decomposition. Mean lignin/weight loss ratios (L/W) and lignin/carbohydrate loss ratios (L/C), were 0.9 and 0.7 for the Basidiomycota and 0.7 and 0.4 for the Xylariaceae, respectively. Significant differences were found in L/W and L/C between the two groups when the result of Xylaria sp. that showed marked delignification was excluded. These differences in lignin and carbohydrate utilization patterns are discussed in relation to the structural and the chemical properties of the decomposed litter and to the implications for organic chemical changes during litter decomposition processes.

Volatile organic compounds from leaves litter.

Qualitative composition of volatile emissions of litter of five species of deciduous trees was investigated by GC-MS. The list of identified substances contains more than 70 organic compounds of various classes. It was established that the composition of components emitted by the litter into the gas phase greatly differs from that of essential oils extracted by hydrodistillation from turned leaves collected from trees during fall. It is suggested that most compounds found in litter emissions are products of vital activity of microorganisms decomposing it. The reported data indicate that after the vegetative period is over the decomposition processes of litter are important seasonal sources of reactive organic compounds under the forest canopy.

Role of litter decomposition for the increased primary production in areas heavily grazed by reindeer: a litterbag experiment

Heavy grazing and trampling by reindeer increase nutrient cycling and primary production in areas where grasslands have replaced shrub and moss tundra. One way in which herbivores can affect nutrient cycling is through changing the litter decomposition processes. We studied the effect of herbivory on litter decomposition rate by reciprocal transplantation of litter between lightly grazed and heavily grazed areas, using the litterbag technique. We used litter from two of the most common species on the lightly grazed side, Betula nana and Empetrum nigrum, and two of the most common species on the heavily grazed side, Carex bigelowii and Deschampsia flexuosa. We found that herbivory improved litter quality by favouring species with easily decomposed litter. However, herbivory also improved litter quality by increasing the nitrogen content and lowering the C/N ratio of each species. Decomposition rates even correlated with the abundance of the plant category in question. Shrub litter decomposed faster in the lightly grazed area where shrubs were common, and graminoid litter decomposed faster in the heavily grazed area where graminoids were common. These results indicate that the decomposer micro‐organisms are adapted to the most common litter types. This study shows that detailed information about the effect of herbivory on litter quality is important to understand differences between the short‐term and long‐term effects of herbivory on nutrient cycling and primary production.

Organic chemical and nutrient dynamics in decomposing beech leaf litter in relation to fungal ingrowth and succession during 3‐year decomposition processes in a cool temperate deciduous forest in Japan

Decomposition processes of beech leaf litter were studied over a 3‐year period in a cool temperate deciduous forest in Japan. Organic chemical and nutrient dynamics, fungal biomass and succession were followed on upper (Moder) and lower (Mull) of a forest slope. Litter decomposition rates were similar between the sites. Nutrient dynamics of the decomposing litter was categorized into two types: weight changes in nitrogen and phosphorus showed two phases, the immobilization (0–21 months) and the mobilization phase (21–35 months), while those in potassium, calcium and magnesium showed only the mobilization phase. The rate of loss of organic chemical constituents was lignin < holocellulose < soluble carbohydrate < polyphenol in order. The changes in lignocellulose index (LCI), the ratio of holocellulose in lignin and holocellulose, were significantly correlated to the changes in nitrogen and phosphorus concentrations during the decomposition. During the immobilization phase, increase in total fungal biomass contributed to the immobilization of nitrogen and phosphorus. The percentage of clamp‐bearing fungal biomass (biomass of the Basidiomycota) to total fungal biomass increased as the decomposition proceeded and was significantly correlated to LCI. Two species in the xylariaceous Ascomycota were dominantly isolated by the surface sterilization method from decomposing litter collected in the 11th month. The organic chemical, nitrogen and phosphorus dynamics during the decomposition were suggested to be related to the ingrowth, substrate utilization and succession of the Xylariaceae and the Basidiomycota. Twenty‐one species in the other Ascomycota and the Zygomycota isolated by the washing method were classified into three groups based on their occurrence patterns: primary saprophytes, litter inhabitants and secondary sugar fungi. These species showed different responses to LCI and soluble carbohydrate concentration of the litter between the groups.

Templates of food–habitat resources for the organization of soil animals in temperate and tropical forests

The functioning and structure of terrestrial ecosystems are shaped and maintained by plant–decomposer interactions. The food and habitat of animal populations are biogenic and are mainly of plant origin (plant litter) in terrestrial ecosystems. Primary resources of the food‐habitat template for the organization of soil animals are provided by the primary production of plants, and are then modified through decomposition processes by microbial populations. In the microbial decomposition system, the efficiency of carbon utilization by microbial decomposers characterizes the decomposition processes between tropical and temperate forest ecosystems. Tropical forests show poor development of soil reservoir systems because of the high efficiency of lignin decomposition by microbial populations. The decomposition processes of leaf litter are described briefly for the understanding of organization of soil animal communities in tropical and temperate forests. A comparison of decomposition processes shows qualitative differences in decomposition between temperate and tropical forests. The composition of functional groups of soil animals is well explained by the decomposition processes in both forests.

Effects of fungal inocula on the decomposition of lignin and structural polysaccharides in Pinus sylvestris litter

Litter bags containing sterile Scots pine (Pinus sylvestris) needles (19.8% lignin, 26.5% cellulose and 0.34% N) were inoculated with two species of fungi in the laboratory and then placed in the litter layer of a pine plantation. Marasmius androsaceus, which can degrade lignocellulose, was initially displaced by other fungal colonisers and was not detected in the litter after 2–3 months; but was re-isolated from the needles after 12 months. Trichoderma viride, which is a cellulolytic species and also antagonistic to other fungi, dominated the litter throughout the experiment. The control litter was naturally colonised by litter fungi. After 12 months, mass losses were similar at 52% for M. androsaceus and 48% for T. viride, compared with 36% for the control litter colonised by a more complex fungal community. Lignin concentrations increased with time in control litter and with T. viride because mass losses of carbohydrates were greater than those of lignin. Litter inoculated with M. androsaceus showed significant lignin decomposition throughout the experiment but cellulose concentrations showed a proportional increase in the first 6 months, suggesting that the fungus was preferentially exploiting hemicellulose and non-structural carbohydrates. Analysis of TFA-extractable sugars (mainly from hemicellulose) and CuO-derived phenylpropanoid moieties from lignin confirmed the differential patterns of resource decomposition which were not evident from total mass losses. During the initial stages of decomposition, T. viride was as effective in utilising structural polysaccharides as the complex fungal community in the control litter. Furthermore, M. androsaceus not only exhibited unexpectedly low cellulolytic activity but also facilitated lignin depolymerisation after the fungus was no longer detectable in the litter. The pre-inoculation of litter with these two fungal species therefore affected the overall dynamics of decomposition at a biochemical level. This study illustrates the importance of understanding the effects and interactions of specific fungi, rather than assumptions about the functional competence of diverse communities, on the processes of litter decomposition.

Land cover change in eastern Kansas: litter dynamics of closed-canopy eastern redcedar forests in tallgrass prairie

In the Great Plains region, eastern redcedar (Juniperus virginiana L.) abundance has increased dramatically in areas historically occupied by tallgrass prairie. This shift in dominant vegetation is likely to be accompanied by changes in ecosystem structure and function, including quantity, quality, and location (above- vs. below-ground) of litter inputs and subsequent effects on decomposition dynamics. The purpose of this study was to quantify and compare patterns of litterfall and decomposition in mature redcedar forests and adjacent prairie. Annual redcedar litterfall was 500 g·m-2·year-1, a large increase in foliar litter inputs compared with annually burned grassland (52 g·m-2·year-1). Using a reciprocal transplant decomposition study with four substrates, redcedar leaves and roots, and big bluestem (Andropogon gerardii Vitman) foliage and roots, we found marginal habitat effects, but greater differences between species, presumably owing to litter quality (including both C:N and lignin content). Decay rates were significantly higher in the prairie relative to the forest for each substrate. Additionally, within any particular habitat, grass litter had significantly faster decay rates than forest litter. These results suggest a shift in patterns of litter input and decomposition processes with afforestation of tallgrass prairie, which may result in long-term changes in C sequestration and storage.Key words: litter dynamics, eastern redcedar (Juniperus virginiana), big bluestem (Andropogon gerardii), decomposition, tallgrass prairie, nitrogen immobilization.