Litter Biomass Research Articles

Impact of Management Practices on Coffee-Pine Agroforestry: Coffee Yield and Soil Respiration

The coffee-pine agroforestry system offers a promising solution to enhance coffee yields and maintain soil health on degraded lands. This study aims to evaluate the impact of various agroforestry management practices on coffee yield and soil respiration. The experiment was conducted using a complete randomized block design across five management treatments: without management, without fertilization, organic fertilization, mixed fertilization, and recommended management by Perhutani. The observed parameters included coffee yield, soil respiration, soil moisture, soil temperature, litter biomass, canopy cover, and soil organic carbon (SOC) content. Results indicated that the recommended management (RM) plot achieved the highest coffee yield (834 kg ha⁻¹), attributed to wider planting spacing, which reduced resource competition between coffee and pine trees. The RM plot also displayed stable soil moisture and temperature, supporting coffee growth. Meanwhile, soil respiration showed no significant differences across treatments, though the mixed fertilization (MF) plot exhibited the highest respiration rate, indicating higher microbial activity due to combined fertilizer use. In conclusion, optimal management in agroforestry systems can enhance coffee productivity while preserving soil health. Keywords: Agroforestry, Coffee Yield, Soil Management, Soil Moisture, Soil Respiration.

High-rate nitrogen loading accelerates organic phosphorus loss through enzymatic and non-enzymatic processes in a semi-arid grassland

High-rate nitrogen loading accelerates organic phosphorus loss through enzymatic and non-enzymatic processes in a semi-arid grassland

Chemical Composition and Decomposition of Litter in Signal Grass Pastures Fertilized with Increasing Nitrogen Doses or Intercropped with Calopo

Knowledge about the decomposition of litter in signal grass pastures is still limited, especially in pastures managed under deferred grazing. Thus, we aimed to evaluate the chemical composition, carbon/nitrogen (C/N) ratio, and decomposition rate of litter in signal grass (Urochloa decumbens cv. Basilisk) pastures not fertilized with N (U0), fertilized with 50 kg·N·ha−1 (U50), fertilized with 100 kg·N·ha−1 (U100), and intercropped with calopo (Calopogonium mucunoides Desv.) (UC), managed under deferred grazing at different incubation times for two experimental periods (2017–2018 and 2018–2019). Data were analyzed using a randomized block experimental design with four management systems and two blocks, each containing two replicates per treatment. Nitrogen sources increased the N concentrations in the litter before incubation. Nitrogen concentrations in the incubated litter were affected by the incubation times and periods, increasing over time, mainly for U50 and U100. U100 litter samples exhibited higher acid detergent insoluble nitrogen (ADIN) levels than the U0 litter samples only in period 2. Notably, the C/N ratio did not differ with the different management systems; however, it decreased with increasing incubation times and periods, with final values of 24:1 and 26:1 in periods 1 and 2, respectively. Overall, litter samples from pastures fertilized with chemical or biological N sources exhibited higher N concentrations, but their incubated litter samples exhibited higher ADIN concentrations. However, management systems did not affect C/N ratios and no differences in litter biomass decomposition were observed among the systems, possibly due to the grazing period occurring prior to litter sampling.

Forest Development Determines the Compositions and Structures of Soil Invertebrate Communities in Reclaimed Coastal Lands

Soil fauna is integral to facilitating material cycles, energy flows, and the conservation of biodiversity in terrestrial ecosystems. However, the impacts of forest development on the compositions and structures of soil invertebrates remain uncertain. Here, we assessed the dynamics in abundance and diversity of soil invertebrates across eight successional age stages of Metasequoia glyptostroboides tree plantations (7-, 16-, 21-, 26-, 31-, 36-, 41-, 46-year-old stands) in a reclaimed coastal land in China. We used pitfall traps to collect soil invertebrates and analyzed key soil and litter properties to understand their relationships with the faunal communities. The results revealed that the total abundance of soil invertebrates initially decreased during the young to near-mature stand period (7- to 31-year-old stands), whereas it increased along the age series, from the near-mature to overmature stand period (31- to 46-year-old stands). Specifically, the dynamics showed a U-shaped curve with stand development. Further, there was a significantly negative correlation between the Shannon–Wiener diversity index and the total abundance of soil invertebrates across this plantation chronosequence. The variations in abundance of detritivores were consistent with the total abundance of soil invertebrates during stand development. The abundance and diversity of the soil invertebrates were strongly correlated with the soil environment (e.g., soil organic carbon, litter biomass, and microbial biomass nitrogen). These findings highlight that the compositions and structures of soil invertebrates were significantly altered with M. glyptostroboides stand development. Thus, the management of plantations should consider the abundance and diversity of soil invertebrates and functional groups for improving soil structure and fertility. This provides important insights for studying the interconnection of above- and below-ground plantation ecosystems toward their optimal management.

Plant Diversity, Productivity, and Soil Nutrient Responses to Different Grassland Degradation Levels in Hulunbuir, China

Grassland degradation could affect the composition, structure, and ecological function of plant communities and threaten the stability of their ecosystems. It is essential to accurately evaluate grassland degradation and elucidate its impacts on the vegetation–soil relationship. In this study, remote sensing data based on vegetation coverage were used to assess the degradation status of Hulunbuir grassland, and five different grassland degradation degrees were classified. Vegetation community composition, diversity, biomass, soil nutrient status, and their relationships in different degraded grasslands were investigated using field survey data. The results showed that grassland degradation significantly affected the species composition of the vegetation community. As degradation intensified, species richness declined, with the proportion of Gramineae and Legume species decreasing and Asteraceae species increasing. Additionally, the proportion of annual species initially increased and then decreased. Degradation also markedly reduced aboveground, belowground, and litter biomass within the communities. Soil moisture, electrical conductivity, organic carbon, total carbon, total potassium, and hydrolyzable nitrogen contents in non-degraded areas were higher than those in severely degraded areas. Conversely, soil total phosphorus content and bulk density gradually increased with degradation. Nitrate nitrogen and ammonium nitrogen levels in severely degraded soils were significantly higher than those in non-degraded soils. Plant diversity in the study area was significantly positively correlated with aboveground biomass and belowground biomass, and it positively correlated with soil nutrient total carbon and available carbon but negatively correlated with soil bulk density. Results of the partial least squares path model showed that grassland degradation had significant negative effects on plant diversity, soil nutrients, and biomass. Soil nutrients were the main factors affecting ecosystem productivity. The direct effect of plant diversity on biomass was not significant, suggesting that soil nutrients may play a more important role than plant diversity in determining biomass during grassland degradation. The results illustrated the relationships among soil nutrients, plant diversity, and biomass in degraded grasslands and emphasized the importance of an integrated approach in the effective management and restoration of degraded grasslands.

Aliphatic carbon regulates soil water repellency in a chronosequence of grassland enclosure in the Loess Hilly Region

Aliphatic carbon regulates soil water repellency in a chronosequence of grassland enclosure in the Loess Hilly Region

Multiple element coupling and molecular-chemical diversity of organic matter control how much energy is retained in soils in mountain ecosystems

Multiple element coupling and molecular-chemical diversity of organic matter control how much energy is retained in soils in mountain ecosystems

Managing fires in a woody encroachment context: Fine fuel load does not change across fire seasons in a Guinean savanna (West Africa)

Fine surface fuels play a key role in driving fire spread, and therefore play an important role in wildfire management in savannas. In protected areas of the Guinean savannas (humid savannas of West Africa), despite prescribed early-dry season (EDS) or mid-dry season fire (MDS), woody encroachment is increasingly occurring. Recently, N'Dri et al. (2022) showed that late-dry season (LDS) fire applied at least three successive years alternating with a maximum of two successives EDS or MDS fires could reduce woody encroachment in protected areas of the regions. However, the relationship between time of burning (TOB) and fine fuel load (standing grass and fallen leaves of grasses and trees) remains uncertain. In a 10-year experimental field study (2013-2023), we monitored fine fuel load under annual fires set in three different TOB within the dry season: EDS, MDS and LDS. We also explored how fuel loads were influenced by fireline intensity and vice-versa, in addition to grass growth dynamic during one year after each fire. Results showed that grass grows faster in height after fires, reaching the highest peak (∼2m) in November regardless of the TOB. Overall, the TOB within the dry season did not affect significantly the total fine fuel load even after 10 years (1.22±0.12, 1±0.09 and 0.96±0.09kgm-2 respectively for EDS, MDS and LDS fires). Nevertheless, in EDS plots, the greatest biomass of grass and litter was generally observed in alternate years. This is most likely due to a high decomposition rate and termite activity which played a rôle in maintaining basic levels. Overall, fireline intensity did not influence the subsequent fine fuel load recorded in November and fine fuel load recorded just before fires did not influence fireline intensity. Given the results of the current study, the best procedure in setting successive fires to reduce woody encroachment in Guinean savannas, remains that of N'Dri et al. (2022).

The role of Acacia crassicarpa plantation forest in Peatland in reducing CO2 emissions

Abstract Acacia crassicarpa is a fast-growing plant on peatlands that is capable of binding atmospheric CO2 and storing it in carbon. The study aims to calculate carbon stocks in Acacia crassicarpa plantations and their potential to absorb atmospheric CO2. The research was performed in an industrial plantation forest in Siak Regency, Riau Province. The observation plots employed stratified random sampling by measuring the height and diameter of Acacia crassicarpa aged 12, 24, 36 and 42 months, as well as the biomass of undergrowth and litter. Stored carbon was estimated by calculating tree biomass through the approach of specific gravity and trees volume, while for understory plants and litter was based on their dry weight. The results exhibited that Acacia crassicarpa aged 12, 24, 36 and 42 months had carbon stocks of 4.14 tons/ha, 18.55 tons/ha, 43.82 tons/ha and 69.39 tons/ha. The ability of the stand to absorb CO2 in the atmosphere is 15.23 tons/ha, 68.08 tons/ha, 160.81 tons/ha, and 254.67 tons/ha. The potential carbon stored in the understory stands at 0.64 tons/ha, 0.79 tons/ha, 0.85 tons/ha, and 0.86 tons/ha. The carbon stored in litter is 0.80 tons/ha, 1.27 tons/ha, 1.49 tons/ha, and 1.5 tons/ha.

A rough calculation of the litter carbon in agarwood small scale forest in Asahan Regency, North Sumatra, Indonesia

Abstract One of the sources of forest carbon is the forest floor, such as dead organic material and litter. The aim of this research is to analyze estimates of litter and soil carbon stocks in small-scale forest agarwood in Asahan, North Sumatra. Laboratory analysis was carried out at the Agricultural Laboratory of the Universitas Sumatera Utara. The analysis of litter biomass is carried out in the laboratory. The average litter carbon on land in Hessa Perlompongan Village is 0.36 tons/ha, which is greater than the average litter carbon on land in Bunut Village, which is 0.19 tons/ha. There is a significant difference between the average carbon biomass of litter carbon in Hessa Perlompongan Village and Bunut Village.

Carbon Reservoirs in the Biomass and Soil in Livestock Systems with Scattered Trees in Pastures in the Humid Tropics of Mexico

Maintaining trees in grassland areas is an option for enhancing carbon stocks, yet the contribution of dispersed trees in pastures has been little studied in livestock systems in the humid tropics of Mexico, despite being one of the region’s most widely employed silvopastoral modalities. We conducted a study to assess biomass and soil carbon storage in a silvopastoral system, consisting of Brachiaria brizantha grass with native trees dispersed in paddocks (STP) and compared the findings with a pastureland consisting of Brachiaria decumbens grass without trees (WT). Five sampling plots of 1000 m2 size, were randomly selected for each livestock system (STP and WT). At each site, tree biomass was estimated by allometric equations, and herbaceous, litter biomass, and soil organic carbon at four dif ferent depths were quantified by direct sampling method. Of the total biomass in the STP, above-ground biomass contributed 57.3%, below-ground biomass 20%, and ground litter 22.7%. In the case of WT, above-ground biomass represented 40.9% of the total biomass, below-ground biomass 6.4%, and litter 52.7%. The STP system stored a total of 162.3 Mg C ha-1, of which 149.7 Mg C ha-1 in the soil to 70 cm depth and 12.7 Mg C ha-1 in the biomass. WT system stored a total of 116.6 Mg C ha-1, of which 110.7 Mg C ha-1 in the soil and 5.5 Mg C ha-1 in the biomass. It is concluded that the STP livestock system increased 28% of the total carbon storage compared to the WT. However, more studies with greater species diversity and at dif ferent densities are needed to understand better the contribution of trees to carbon accumulation in livestock systems.

Estimating vegetation and litter biomass fractions in rangelands using structure-from-motion and LiDAR datasets from unmanned aerial vehicles

ContextThe invasion of annual grasses in western U.S. rangelands promotes high litter accumulation throughout the landscape that perpetuates a grass-fire cycle threatening biodiversity.ObjectivesTo provide novel evidence on the potential of fine spatial and structural resolution remote sensing data derived from Unmanned Aerial Vehicles (UAVs) to separately estimate the biomass of vegetation and litter fractions in sagebrush ecosystems.MethodsWe calculated several plot-level metrics with ecological relevance and representative of the biomass fraction distribution by strata from UAV Light Detection and Ranging (LiDAR) and Structure-from-Motion (SfM) datasets and regressed those predictors against vegetation, litter, and total biomass fractions harvested in the field. We also tested a hybrid approach in which we used digital terrain models (DTMs) computed from UAV LiDAR data to height-normalize SfM-derived point clouds (UAV SfM-LiDAR).ResultsThe metrics derived from UAV LiDAR data had the highest predictive ability in terms of total (R2 = 0.74) and litter (R2 = 0.59) biomass, while those from the UAV SfM-LiDAR provided the highest predictive performance for vegetation biomass (R2 = 0.77 versus R2 = 0.72 for UAV LiDAR). In turn, SfM and SfM-LiDAR point clouds indicated a pronounced decrease in the estimation performance of litter and total biomass.ConclusionsOur results demonstrate that high-density UAV LiDAR datasets are essential for consistently estimating all biomass fractions through more accurate characterization of (i) the vertical structure of the plant community beneath top-of-canopy surface and (ii) the terrain microtopography through thick and dense litter layers than achieved with SfM-derived products.

Regional and local patterns of soil arthropod diversity are explained by different processes in southwest China

Regional and local patterns of soil arthropod diversity are explained by different processes in southwest China

Natural grassland restoration exhibits enhanced carbon sequestration and soil improvement potential in northern sandy grasslands of China: An empirical study

Natural grassland restoration exhibits enhanced carbon sequestration and soil improvement potential in northern sandy grasslands of China: An empirical study

Potential Benefits of Forest Litter Biomass in Agriculture

Potential Benefits of Forest Litter Biomass in Agriculture

Contribution of Litter and Root to Soil Nutrients in Different Rocky Desertification Grasslands in a Karst Area.

Litter and root decomposition is an important source of soil organic matter and nutrients. To ascertain the contribution of litter and root to natural grassland nutrients in rocky desertification areas, from March 2017 to January 2018, the continuous soil column method, collector method, and litter decomposition method were used to study the soil nutrients, litter and root biomass, decomposition, and nutrient release of potential, moderate, and severe rocky desertification grasslands, as well as their responses to rocky desertification. The results showed that the litter and root decomposition rate showed a trend of being first fast and then slow, and the decomposition rate of litter and root was greater than 50% after 300 days. The annual litter decomposition rates of potential, moderate, and severe rocky desertification grasslands were 69.98%, 62.14%, and 49.79%, respectively, and the annual decomposition rates of root were 73.64%, 67.61%, and 64.09%, respectively. With a deepening degree of rocky desertification, the litter and root decomposition rate decreased. The decomposition coefficients, k, of litter in potential, moderate, and severe rocky desertification grasslands were 1.128, 0.896, and 0.668, respectively, and the decomposition coefficients, k, of root were 1.152, 1.018, and 0.987, respectively. The nutrient release processes of litter and root were different, and the release mode ultimately manifests as "release". In rocky desertification grasslands, the organic carbon (OC), total nitrogen (TN), total phosphorus (TP), and total potassium (TK) released by litter and root decomposition were 18.93-263.03 g·m-2·yr-1, 1.79-5.59 g·m-2·yr-1, 0.18-0.47 g·m-2·yr-1, and 0.66-3.70 g·m-2·yr-1, respectively. The contribution of root to soil nutrients was greater than that of litter. The degree of rocky desertification was negatively correlated with the biomass, decomposition rate, and nutrient return amount of litter and root. The results of this study provide direct field evidence and illustrate the contribution of litter and root decomposition in rocky desertification grasslands to soil nutrients.

Grazing period management affects the accumulation of plant functional groups, and soil nutrient pools and regulates stoichiometry in the desert steppe of Northwest China

To understand how nutrient cycling and sequestration are influenced by different grazing periods, the C:N:P stoichiometry features of the plant-soil interface in the desert steppe were measured and evaluated. The 5-year seasonal grazing experiment employed four grazing period treatments: traditional time of grazing (TG), early termination of grazing (EG), delayed start of grazing (DG), and delayed start and early termination of grazing (DEG). Additionally, fenced off desert steppe served as the control. The grazing periods each had a differing impact on the C:N:P stoichiometry in both plant functional group and soil depth comparisons. Compared to the EG, DG, and DEG treatments, the TG treatment had a more significant impact on the C, N, and P pools of grass, as well as the C:P and N:P ratios of forbs, but had a reduced effect on the C:P and N:P ratios of legumes. In contrast to plants, the DG treatment exhibited greater advantages in increasing C pools within the 0-40cm soil layer. Furthermore, in the 10-20cm soil layer, the C:P and N:P ratios under the EG treatment were significantly higher, ranging from 8.88% to 53.41% and 72.34%-121.79%, respectively, compared to the other treatments (TG, DG, and DGE). The primary drivers of the C, N, and P pools during different grazing periods were above-ground biomass (AGB) and litter biomass (LB). Both lowering the plant C:P and N:P ratios and considerably raising the plant P pool during different grazing periods greatly weakened the P limitation of the desert steppe environment. It is predicted that delayed start grazing might be a management strategy for long-term ecosystem sustainability, as it regulates above-ground nutrient allocation and has a positive effect on soil C and N pools.

Fire exclusion alters forest evapotranspiration: A comprehensive water budget analysis in longleaf pine woodlands

AbstractForests are critical to water resources, but high evapotranspiration (ET) can reduce water yield. Thinning and prescribed fire reduce forest density and often reduce ET, promoting higher water yield. However, results from such treatments have been inconsistent, possibly because of unknown interactions among individual ET components. We compare water budget components of longleaf pine (Pinus palustris Mill.) woodlands with frequent prescribed fire to the water budget components of fire‐excluded stands. We hypothesized that fire exclusion would result in higher ET due to increased midstory transpiration (Et) and interception (Ei), and higher evaporation from litter (Ilitter). Reference plots were burned every two years while treatment plots had fire excluded for 15–20 years. Fire treatments were repeated in two sites representing a soil moisture gradient, noted as mesic and xeric. We measured woody Et using sap flux, and we modeled groundcover Et using physiological models. We measured Ei of canopy and groundcover layers, modeled Es litter biomass, and constructed a total component‐based water budget for each site and treatment. Compared with reference plots, midstory Et was 300%–800% higher in fire exclusion plots. Groundcover Et was ~80% less than reference treatments, countering the effects of midstory growth on total ET. Stand Ei followed similar trends, with groundcover Ei in reference plots countering the effects of midstory and litter Ei in fire exclusion plots. As expected, total ET in the xeric site was 18% higher in fire exclusion plots. However, ET in the mesic site was 16% lower in the fire exclusion plots due to high groundcover Et and Ei in reference plots. Thus, our results show that fire exclusion changes total forest ET, but the size and direction of the effect vary depending on the balance between midstory and groundcover transpiration and interception. These results highlight the importance of groundcover in ecosystem function in low‐density forests and may help explain inconsistent results from studies of water yields following thinning and fire. While prescribed fire is a valuable tool in forest management, we suggest that the effects of fire on ET are complex and require careful accounting of all water fluxes within a forest ecosystem.

Association of Carbon Pool with Vegetation Composition along the Elevation Gradients in Subtropical Forests in Pakistan

As the most important way to mitigate climate change, forest carbon storage has been the subject of extensive research. A comprehensive study was carried out to investigate the influence of elevation gradients and diameter classes on the forest growth, composition, diversity, and carbon pools of the Bagh Drush Khel Forest area. Research revealed that elevation gradients significantly influenced the composition, diversity, and carbon pools in forests. At lower elevations, Eucalyptus camaldulensis was the dominant species, with Olea ferruginea as a co-dominant species, whereas at higher elevations, Pinus roxburghii was the dominant species with Quercus incana as a co-dominant species. Regeneration was higher at higher elevations with the maximum number of saplings and seedlings of P. roxburghii. Species diversity association with elevation was negative (R2 = −0.44; p < 0.05—Shannon Index). Soil organic carbon (SOC association with elevation was non-significant while positive with DBH classes (R2 = 0.37; p < 0.05). Overall, carbon pool association with elevation and diameter at breast height (DBH) were negative (R2 = −0.73; p < 0.05) and (R2 = −0.45; p < 0.05). Litter biomass correlated positively with elevation (R2 = 0.25; p < 0.05) and DBH (R2 = 0.11; p < 0.05), while deadwood biomass correlated negatively with elevation gradients (R2 = −0.25; p < 0.05), and no effect was observed for DBH classes. The highest carbon stock (845.89 t C/ha) was calculated at low elevations, which decreased to (516.27 t C/ha) at high elevations. The overall carbon stock calculated was (2016.41 t C/ha) respectively. A total of six tree species were found at the study site. Future research is essential for forest health monitoring and understanding fine-scale impacts. This study offers a methodological framework for similar investigations in unexplored yet potentially significant forest regions worldwide.

Biomass and Carbon Stock Capacity of Robinia pseudoacacia Plantations at Different Densities on the Loess Plateau

Forests make an important contribution to the global carbon cycle and climate regulation. Caijiachuan watershed false acacia (Robinia pseudoacacia Linn.) plantation forests have been created for 30 years, but a series of problems have arisen due to the irrationality of the density involved at that time. To precisely assess the contribution of R. pseudoacacia plantations with different densities to this cycle, we measured the diameter at breast height (DBH), tree height (H), biomass, and carbon stocks in trees, shrubs, herbs, litter, and soil across different density ranges, denoted as D1 = 900–1400, D2 = 1401–1900, D3 = 1901–2400, D4 = 2401–2900, and D5 = 2901–3400 trees ha−1. In order to achieve the purpose of accurately estimating the biomass, carbon stocks and the contribution rate of each part in different densities of R. pseudoacacia plantations were measured. The results are as follows: (1) Both DBH and H decreased with increasing density, and field surveys were much more difficult and less accurate for H than DBH. Based on the two allometric growth models, it was found that the determination coefficient of the biomass model that incorporated both H and DBH (0.90) closely resembled that of the model using only DBH (0.89), with an error margin of only 0.04%. (2) At the sample scale, stand density significantly affected R. pseudoacacia stem biomass and total biomass. At the individual plant scale, stand density significantly affected R. pseudoacacia organ biomass. Increasing stand densities promoted the accumulation of vegetation biomass within the sample plot but did not improve the growth of individual R. pseudoacacia trees. The stem biomass constituted the majority of the total R. pseudoacacia biomass (58.25%–60.62%); the total R. pseudoacacia biomass represented a significant portion of the vegetation biomass (93.02%–97.37%). (3) The total carbon stock in the sample plots tended to increase with increasing stand density, indicating a positive correlation between density and the carbon stock of the whole plantation forest ecosystem. Hence, in future R. pseudoacacia plantations, appropriate densities should be selected based on specific objectives. For wood utilization, a planting density of 900–1400 trees ha−1 should be controlled. For carbon fixation, an initial planting density of 2900–3400 trees ha−1 should be selected for R. pseudoacacia. This study provides theoretical support for local forest management and how to better sequester carbon.