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A) Correlation between remaining mass of tea litter of different qualities (green and rooibos tea) after 3 month of incubation during the growing season. Symbols are arithmetic means for each biome and error bars indicate ± standard deviation. B) The average remaining mass aggregated by biome of Green tea (dashed line) and Rooibos tea (solid line) plotted against the mean annual precipitation for each biome (Table 1). The regression line is from a simple linear model showing significant effects for Green (R 2 = 0.40) and Rooibos (R 2 = 0.64).
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Through litter decomposition enormous amounts of carbon is emitted to the atmosphere. Numerous large-scale decomposition experiments have been conducted focusing on this fundamental soil process in order to under-stand the controls on the terrestrial carbon transfer to the atmosphere. However, previous studies were mostly based on site-specific litt...
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Context 1
... analyzed the across-site variation in initial litter mass loss at the site and biome scales. In this study, investigated sites are spread across large temperature and moisture gradi- ents. We observed an effect of precipitation on early stage lit- ter mass loss, while temperature did not show any significant effects (Fig. 3). Mean annual temperatures of b10 °C and mois- ture contents of b30% or N80% have been suggested as inhibiting thresholds for litter decay (Prescott, 2010). The ab- sence of any significant effect of temperature on litter mass loss in our study may be a consequence of the fact that all sites incubated the tea bags during the "summer" under rela- tively favorable conditions where temperature values were gen- erally within the "optimal" decay range. Furthermore, large variation in litter mass loss was observed for both litter types within any given biome (Fig. 5a, Table 2) suggesting that local-scale factors (e.g. soil properties, soil water content, dis- turbances) other than climate had strong controls on regional litter mass loss dynamics ( Cornwell et al., 2008). Similarly, Ise and Moorcroft (2006) reported a low temperature sensitivity of decomposition (Q 10 = 1.37) at the global scale. On the other hand, when examined separately, climate explained 40% Table 1). The regression line is from a simple linear model showing significant effects for Green (R 2 = 0.40) and Rooibos (R 2 = 0.64). of the variation for Green tea and 64% for Rooibos tea when the mean litter mass loss values were used for the given biome ( Fig. 5b, Table 3). A similar finding was reported by Bradford et al. (2014), where the explanatory power of climate was increased to 84% when analyses were conducted on aggre- gated data. Interestingly, early-stage litter mass loss of both litter types were comparable across all biomes (Fig. 3). The relative mass losses observed in the arctic sites may seem surprisingly high relative to the other warmer biomes. However, the study was carried out in the "summer season" where climatic conditions, even at the arctic sites are rather mild and warm and therefore favorable for decomposition (Couteaux et al., 1995). On the contrary, sites in the warmer biomes received less precipitation in the summer often being below potential evapotranspiration and leading to soil moisture deficit which again may result in lower mass losses. However, it has to be kept in mind that the results for arctic and arid-temperate biomes are based on a lower number of sites and should be interpreted with ...
Context 2
... analyzed the across-site variation in initial litter mass loss at the site and biome scales. In this study, investigated sites are spread across large temperature and moisture gradi- ents. We observed an effect of precipitation on early stage lit- ter mass loss, while temperature did not show any significant effects (Fig. 3). Mean annual temperatures of b10 °C and mois- ture contents of b30% or N80% have been suggested as inhibiting thresholds for litter decay (Prescott, 2010). The ab- sence of any significant effect of temperature on litter mass loss in our study may be a consequence of the fact that all sites incubated the tea bags during the "summer" under rela- tively favorable conditions where temperature values were gen- erally within the "optimal" decay range. Furthermore, large variation in litter mass loss was observed for both litter types within any given biome (Fig. 5a, Table 2) suggesting that local-scale factors (e.g. soil properties, soil water content, dis- turbances) other than climate had strong controls on regional litter mass loss dynamics ( Cornwell et al., 2008). Similarly, Ise and Moorcroft (2006) reported a low temperature sensitivity of decomposition (Q 10 = 1.37) at the global scale. On the other hand, when examined separately, climate explained 40% Table 1). The regression line is from a simple linear model showing significant effects for Green (R 2 = 0.40) and Rooibos (R 2 = 0.64). of the variation for Green tea and 64% for Rooibos tea when the mean litter mass loss values were used for the given biome ( Fig. 5b, Table 3). A similar finding was reported by Bradford et al. (2014), where the explanatory power of climate was increased to 84% when analyses were conducted on aggre- gated data. Interestingly, early-stage litter mass loss of both litter types were comparable across all biomes (Fig. 3). The relative mass losses observed in the arctic sites may seem surprisingly high relative to the other warmer biomes. However, the study was carried out in the "summer season" where climatic conditions, even at the arctic sites are rather mild and warm and therefore favorable for decomposition (Couteaux et al., 1995). On the contrary, sites in the warmer biomes received less precipitation in the summer often being below potential evapotranspiration and leading to soil moisture deficit which again may result in lower mass losses. However, it has to be kept in mind that the results for arctic and arid-temperate biomes are based on a lower number of sites and should be interpreted with ...
Context 3
... contrast, the biome-scale analyses focusing on the mean values for the given biome revealed some variation in remaining litter mass loss from low (equatorial humid climate) to high (arid subtropical and Mediterranean climates) mass losses (Fig. 5a). In the linear models, we found a non-significant interaction between tea type and MAP (F = 0.20, P = .66); and between tea types and MAT (F = 0.39, P = .54). Whereas MAT had no effect (F = 0.64, P = .43), re- maining mass decreased with increasing MAP for both tea types (Table ...
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Citations
... Ecosystem type and climate were important factors in previous shorterterm tea litter decay studies (3−12 months). 43,51 Therefore, the first model included the following terms: precipitation, temperature, temperature variability (as standard deviation), ecosystem type, and two-way interactions between ecosystem type and each of the three local climate terms to compare the sensitivity of the ecosystem types to the climatic factors. The macroalgal ecosystems were represented by only two sites each, so they were removed for this analysis. ...
Patchy global data on belowground litter decomposition dynamics limit our capacity to discern the drivers of carbon preservation and storage across inland and coastal wetlands. We performed a global, multiyear study in over 180 wetlands across 28 countries and 8 macroclimates using standardized litter as measures of “recalcitrant” (rooibos tea) and “labile” (green tea) organic matter (OM) decomposition. Freshwater wetlands and tidal marshes had the highest tea mass remaining, indicating a greater potential for carbon preservation in these ecosystems. Recalcitrant OM decomposition increased with elevated temperatures throughout the decay period, e.g., increase from 10 to 20 °C corresponded to a 1.46-fold increase in the recalcitrant OM decay rate constant. The effect of elevated temperature on labile OM breakdown was ecosystem-dependent, with tidally influenced wetlands showing limited effects of temperature compared with freshwater wetlands. Based on climatic projections, by 2050 wetland decay constants will increase by 1.8% for labile and 3.1% for recalcitrant OM. Our study highlights the potential for reduction in belowground OM in coastal and inland wetlands under increased warming, but the extent and direction of this effect at a large scale is dependent on ecosystem and OM characteristics. Understanding local versus global drivers is necessary to resolve ecosystem influences on carbon preservation in wetlands.
... Two kinds of tea bags representing fast (green tea) and slow (rooibos tea) decomposition substrates as standard materials are used. Studies on tea bag experiments confirm that the main drivers of litter decomposition are litter quality, soil characteristics, climate, incubation time and tree age and species (Djukic et al. 2018;Duddigan et al. 2020;Desie et al. 2023). Processes such as litter decomposition have been investigated less intensively in temperate AC while it may be an integrative indicator for estimating changes on overall biological activity following tree establishment. ...
... Tea mass loss variation at different depths are multifactorial but fine roots contribute Regardless of soil depth, the mass loss of tea mostly varied according to the type of tea with a slower decomposition for rooibos than for green tea (Fig. 4). These results were consistent with the conclusions of other studies examining the decomposition of both tea types in agroecosystems (Djukic et al. 2018;Mac-Donald et al. 2018;Duddigan et al. 2020;Fanin et al. 2020;Desie et al. 2023). They explained this difference by the higher lability (Keuskamp et al. 2013) and lower C/N ratio (Duddigan et al. 2020) of green tea compared to rooibos, as we also observed ( Table 2). ...
Background and Aims
Litter decomposition is poorly investigated in young temperate alley cropping (AC) systems but may be an integrative indicator to explore the early effect of trees on overall biological activity throughout soil profile. We evaluated the effect of four-year-old trees on recalcitrant-rooibos and labile-green tea mass loss at different soil depths at the Ramecourt AC experimental site.
Methods
In May 2021, tea bags were inserted within aluminum ingrowth bags and incubated at three depths 1.5 m from a reference tree for 6 months. The tea mass loss variability was analyzed according to factors: type of tea, type of system (AC, sole-crop control or CC and forest plantation control or FC), soil incubation depth, tree species and was correlated with fine roots and soil parameters.
Results
At 30 cm depth, the mass loss was significantly lower for rooibos than green tea regardless of the type of system, whereas at 50 cm and 100 cm depth, this difference was observed only in AC and FC. We observed a lower rooibos mass loss in AC than in CC at 100 cm depth. At 30 cm depth, soil mineral nitrogen content explained 23% of the rooibos tea mass loss variability whereas, soil organic matter content and fine root biomass within tea bags accounted for 50% of green tea mass loss variability.
Conclusion
We highlighted the ability of AC to slow recalcitrant litter decomposition in depth, however further works are needed to elucidate the processes leading to retarded decomposition.
... tea or wooden dowels) can be decomposed in different climates (e.g. Pérez-Harguindeguy et al., 2007;Djukic et al., 2018). However, this method only addresses short-term climate effects without considering the role of litter quality. ...
... For evergreen species, green leaves were collected. In addition, Lipton® green tea (Camellia sinensis, EAN Nr.: 8 722700 055525, from here on "tea") was used as a standard litter (Keuskamp et al., 2013;Djukic et al., 2018) to help separating litter origin and climate effects. The collected litter and tea bags were dried to a stable weight for 72 hours at 40°C, and depending on leaf size, leaf weight and availability of dry litter 1, 2 or 2.5 g (± 0.005 g the exact initial weight was recorded) were bagged in 2 mm polyester mesh. ...
... teabags, cellulose disks, wooden dowels or litter from the same species) is quicker on wetter ends of a climate gradient (e.g. Berg et al., 1993;Gallardo and Merino, 1993;Pérez-Harguindeguy et al., 2007;Powers et al., 2009;Jentsch et al., 2011;Djukic et al., 2018). Interestingly, the litter mass loss observed at our arid and semi-arid sites was almost twice as high as in Israeli (semi-)arid climates which receive similar mounts of precipitation (Steinberger, Shmida and Whitford, 1990), or a Mexican (semi-)arid site that receives five times more precipitation than our sites (Vanderbilt et al., 2008). ...
Climate change is likely to alter plant composition, productivity and litter decomposition. As
ecosystems are shaped by specific small-scale climatic environments, the responses of plants to
climate changes are likely system specific. Inter-annual precipitation is expected to become more
variable with longer dry spells and sporadic but intense precipitation events. It is therefore
important to understand the responses of plant communities to climate change in both directions
(drought and sporadic but intense precipitation). Litter decomposition, a key component of the
global carbon cycle, is greatly affected by the interplay of climate, decomposers and litter quality.
Unfortunately, our current understanding of climate-change effects on plant composition and
litter decomposition stems mainly from space-for-time studies along climate gradients, where
biotic and climatic effects on litter decomposition are confounded. Experimental studies
separating indirect from direct climate effects are needed that test the validity of the space-for-
time approach.
In order to assess the influence of the magnitude of climate change on biomass production and
community composition (richness, diversity and evenness) I translocated soil from two climates
at a micro-climatic (opposite slopes) and a macro-climatic scale (among climates) in chapter 2. I
found that plant communities do not respond to micro-climatic changes, except for biomass
production, which was unexpectedly consistently higher on the drier slopes than on the wetter
slopes. Macro-climatic changes triggered several responses: species richness had a consistent
response to climate change and was higher in the semi-arid climate in both translocations, but
diversity and evenness had contradicting, non-opposite responses. The non-generality of
responses might be an indication that changes that occur during drier years are not easily
recuperated during wetter years.
In the third chapter, I test the hypothesis 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. Although widely tested in temperate forests, this hypothesis remains controversial and
lacks a deep understanding of its generality across climates. I therefore tested the HFA hypothesis
for litter decomposition in four ecosystems along an extensive climatic gradient in Chile, using a
translocation experiment involving litter from 20 species. In addition to comparing mass loss, I
adopted a novel way to disentangle decomposer effects from climate effects, based on loss rates
of decomposable vs. leachable nutrient fractions. I used the ratios of N and K losses and P and K
losses to unravel the relative role of biotic mineralization (N and P loss) vs. physical leaching (K
loss, driven by precipitation) along the climate gradient. My findings unequivocally contradicted
the HFA hypothesis across a wide range of environments and 20 different litter types. A HFA
effect was not found, and litter quality 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 the HFA.
In the fourth chapter I combined large- and small scale reciprocal litter translocations, in situ
precipitation manipulation, and a prominent climate gradient to study climate effects on litter
decomposition. Interestingly, all experiments indicated clear positive effects of precipitation on
decomposition, but the decomposition of local litter at their home site indicated the opposite,
due to indirect climate effects on litter quality. This indicates that space cannot substitute for
time and highlights the need for experimental evidence in litter decomposition studies. Such
evidence would improve predictions of models of the global carbon cycle that include
interactions between climate and vegetation.
Even though plant communities and soil properties seem relatively robust to cope with inter-
annual precipitation variability, the predicted precipitation variability for the next decades will
most likely alter decomposition rates, which will affect carbon and nutrient cycling. To better
predict the influence of climate change on the nutrient cycle, future studies should quantify litter
production and plant community changes. A combination of a detailed quantification of plant
community litter production with observations, translocations and manipulations of litter
decomposition, will make it possible to correctly estimate the effect of future climate change on
the nutrient cycle.
... In previous studies using the TBI approach, it has been shown that climate plays a significant role on decomposition in a temperate biome (Djukic et al., 2018); however, when comparing several different biomes, climatic conditions were of relatively low importance (Fanin et al., 2020). In boreal soils, Althuizen et al. (2018) found that increased temperatures enhanced k, whereas increased precipitation decreased k across years. ...
... Our results revealed that a large number of management practices significantly affected both the decomposition rate (k) and stabilization factor (S), according to the TBI approach, in several LTEs in Austria and Sweden (Figs. 2,3,5). This is in contrast with studies by Djukic et al. (2018) and Saint-Laurent and Arsenault-Boucher (2020), who did not find any significant effect of land use or management practice on early-stage litter decomposition in a temperate biome. ...
Litter decomposition is an important factor affecting local and global C cycles. It is known that decomposition through soil microbial activity in ecosystems is mainly influenced by soil type and climatic conditions. However, for agroecosystems, there remains a need for a better understanding of how management practices influence litter decomposition. This study examined the effect of different management practices on decomposition at 29 sites with long-term (mean duration of 38 years) field experiments (LTEs) using the Tea Bag Index (TBI) protocol with standard litter (rooibos and green tea) developed by Keuskamp et al. (2013). The objective was to determine if the TBI decomposition rate (k) and stabilization factor (S) are sensitive enough to detect differences in litter decomposition between management practices as well as how they interact with edaphic factors, crop type and local climatic conditions. Tea bags were buried and collected after ∼90 d at 16 Austrian and 13 Swedish sites. The treatments in the Austrian LTEs focused on mineral and organic fertilizer application, tillage systems and crop residue management, whereas those in Sweden addressed cropping systems, mineral fertilizer application and tillage systems. The results for Austria showed that the incorporation of crop residue and high-N fertilizer application increased k, compared with crop residue removal and low or no N application, respectively. Minimum tillage had significantly higher k compared with reduced and conventional tillage. In Sweden, fertilized plots showed higher S than non-fertilized plots and high-N fertilizer had the highest k. Growing spring cereal led to higher k than forage crops. Random forest regressions for Austria and Sweden jointly showed that k and S were mainly governed by climatic conditions, which explained more than 70 % of their variation. However, under similar climatic conditions, management practices strongly influenced decomposition dynamics. It would be appropriate to apply the TBI approach to a more large-scale network using LTEs for agroecosystems, in order to improve the index's usefulness as an indicator of the effect of management practices on litter decomposition dynamics, particularly linking it with the potential for C storage.
... This creates uncertainties in model outcomes and large, uniform datasets are crucial to impart hitherto poorly understood interactions between environmental factors, litter quality and decomposition (Heimann & Reichstein, 2008;Le Noë et al., 2023). These limitations in our current understanding of litter decomposition are reflected in the large range (50%-71%) of variation in mass loss explained by either litter type, climate or their combination across existing global studies (Berg et al., 1993;Djukic et al., 2018;Kwon et al., 2021;Parton et al., 2007;Trofymow et al., 2002). ...
The breakdown of plant material fuels soil functioning and biodiversity. Currently, process understanding of global decomposition patterns and the drivers of such patterns are hampered by the lack of coherent large-scale datasets. We buried 36,000 individual litterbags (tea bags) worldwide and found an overall negative correlation between initial mass-loss rates and stabilization factors of plant-derived carbon, using the Tea Bag Index (TBI). The stabilization factor quantifies the degree to which easy-to-degrade components accumulate during early-stage decomposition (e.g. by environmental limitations). However, agriculture and an interaction between moisture and temperature led to a decoupling between initial mass-loss rates and stabilization, notably in colder locations. Using TBI improved mass-loss estimates of natural litter compared to models that ignored stabilization. Ignoring the transformation of dead plant material to more recalcitrant substances during early-stage decomposition, and the environmental control of this transformation, could overestimate carbon losses during early decomposition in carbon cycle models.
... This creates uncertainties in model outcomes and large, uniform datasets are crucial to impart hitherto poorly understood interactions between environmental factors, litter quality and decomposition (Heimann & Reichstein, 2008;Le Noë et al., 2023). These limitations in our current understanding of litter decomposition are reflected in the large range (50%-71%) of variation in mass loss explained by either litter type, climate or their combination across existing global studies (Berg et al., 1993;Djukic et al., 2018;Kwon et al., 2021;Parton et al., 2007;Trofymow et al., 2002). ...
The breakdown of plant material fuels soil functioning and biodiversity. Currently, process understanding of global decomposition patterns and the drivers of such patterns are hampered by the lack of coherent large‐scale datasets. We buried 36,000 individual litterbags (tea bags) worldwide and found an overall negative correlation between initial mass‐loss rates and stabilization factors of plant‐derived carbon, using the Tea Bag Index (TBI). The stabilization factor quantifies the degree to which easy‐to‐degrade components accumulate during early‐stage decomposition (e.g. by environmental limitations). However, agriculture and an interaction between moisture and temperature led to a decoupling between initial mass‐loss rates and stabilization, notably in colder locations. Using TBI improved mass‐loss estimates of natural litter compared to models that ignored stabilization. Ignoring the transformation of dead plant material to more recalcitrant substances during early‐stage decomposition, and the environmental control of this transformation, could overestimate carbon losses during early decomposition in carbon cycle models.
... This creates uncertainties in model outcomes and large, uniform datasets are crucial to impart hitherto poorly understood interactions between environmental factors, litter quality and decomposition (Heimann & Reichstein, 2008;Le Noë et al., 2023). These limitations in our current understanding of litter decomposition are reflected in the large range (50%-71%) of variation in mass loss explained by either litter type, climate or their combination across existing global studies (Berg et al., 1993;Djukic et al., 2018;Kwon et al., 2021;Parton et al., 2007;Trofymow et al., 2002). ...
The breakdown of plant material fuels soil functioning and biodiversity. Currently, process understanding of global decomposition patterns and the drivers of such patterns are hampered by the lack of coherent large-scale datasets. We buried 36,000 individual litterbags (tea bags) worldwide and found an overall negative correlation between initial mass-loss rates and stabilization factors of plant-derived carbon, using the Tea Bag Index (TBI). The stabilization factor quantifies the degree to which easy-to-degrade components accumulate during early-stage decomposition (e.g. by environmental limitations). However, agriculture and an interaction between moisture and temperature led to a decoupling between initial mass-loss rates and stabilization, notably in colder locations. Using TBI improved mass-loss estimates of natural litter compared to models that ignored stabilization. Ignoring the transformation of dead plant material to more recalcitrant substances during early-stage decomposition, and the environmental control of this transformation, could overestimate carbon losses during early decomposition in carbon cycle models.
... As such, the rate of litter carbon release partly determines the terrestrial carbon balance and its feedback to climate change. The observation and prediction of litter mass and nutrient loss have been enduring topics (Djukic et al., 2018;Lajtha et al., 2018;Parton et al., 2007), with many conceptual and mechanistic models being proposed and applied (Olson, 1963;Parton et al., 1993;Rovira & Rovira, 2010;Tuomi et al., 2009). However, a notable gap persists in obtaining accurate estimates of the global-scale litter carbon release rate and its covariation with climate, leading to significant uncertainty in the future climate forecasts using Earth system models. ...
With over one‐third of terrestrial net primary productivity transferring to the litter layer annually, the carbon release from litter serves as a crucial valve in atmospheric carbon dioxide concentrations. However, few quantitative global projections of litter carbon release rate in response to climate change exist. Here, we combined a global foliar litter carbon release dataset (8973 samples) to generate spatially explicitly estimates of the response of their residence time ( τ ) to climate change. Results show a global mean litter carbon release rate () of 0.69 year ⁻¹ (ranging from 0.09–5.6 year ⁻¹ ). Under future climate scenarios, global mean τ is projected to decrease by a mean of 2.7% (SSP 1–2.6) and 5.9% (SSP 5–8.5) during 2071–2100 period. Locally, the alleviation of temperature and moisture restrictions corresponded to obvious decreases in τ in cold and arid regions, respectively. In contract, τ in tropical humid broadleaf forests increased by 4.6% under SSP 5–8.5. Our findings highlight the vegetation type as a powerful proxy for explaining global patterns in foliar litter carbon release rates and the role of climate conditions in predicting responses of carbon release to climate change. Our observation‐based estimates could refine carbon cycle parameterization, improving projections of carbon cycle–climate feedbacks.
... We used the tea bag index (TBI) to investigate litter decomposition processes along the elevation of each mountain by following the protocol from Keuskamp et al. (2013). In this approach, two types of teabags (green tea: EAN8722700055525 and rooibos tea: EAN8722700188438) were used as standard leaf litter bags, which can be used globally and across biomes to generate comparable results (Keuskamp et al. 2013, Djukic et al. 2018. The material of the teabag is made of polypropylene and has a mesh size of 0.25 mm allowing the access of microfauna, microbes, and very fine roots (Fig 1c, d). ...
Forest litter decomposition is considered as an essential ecosystem process affecting carbon and nutrient cycling in mountains. However, there exists high uncertainty in accurately estimating the contribution of litter decomposition to terrestrial ecosystems, largely due to the incomparability of different studies and the data limitation in microclimate and non-climatic factors at spatially matched scales. Here we used the tea bag index (TBI) as a standardized protocol to evaluate spatial variations in forest litter decomposition rate (k) and stabilization factor (S) across 10 mountains spanning a wide range of subtropical and tropical forests. Based on the coordinated experiment of 6,864 teabags in 568 sampling sites along elevations, we evaluated the importance of 10 environmental factors covering soil microclimate, edaphic properties, plant diversity, and topography on k and S by using model averaging and linear-mixed effects models. Of the 10 mountains, we found a consistently decreasing pattern of k and an increasing pattern for S along elevations. And the significant effect of k with elevation was mainly found in the western and northmost mountains, while the effect of S occurred in the western and southernmost mountains. For microclimate, there was a general importance of soil temperature (coef. = 0.48) and temperature variation in the growing season (coef. = 0.36) in k, and soil temperature (coef. = -0.46) and moisture variation on S (coef. = -0.36). The dominant role of soil microclimate was mainly found in western mountains with relatively cold environments. For non-climatic drivers, a significant effect of tree diversity on k and a negative correlation of edaphic and topography with S in the western and southern mountains were detected. These findings provide a general understanding of spatial variations of driving factors in forest litter decomposition and highlight a dominant control of soil microclimate in cold forests in high elevations and latitudes.
... The use of litter decomposition and the Tea Bag Index (TBI) (Keuskamp et al., 2013) as a soil health assessment tool is increasingly popular in both academic and citizen science applications (Djukic et al., 2018;Dossou-Yovo et al., 2021;Daebeler et al., 2022). The TBI protocol posits that soil health positively covaries with the decomposition rate of litter material. ...
... Between 65 and 77 % of decomposition rate variance has been attributed to climate and the chemical composition of organic matter (Moorhead et al., 1999;Djukic et al., 2018;Petraglia et al., 2019), but significant variance can occur at the microsite level (Aguilar-Cruz et al., 2020;Lo Cascio et al., 2021). For example, litter decomposition associated with changes in livestock grazing is site dependent. ...
