Leaf Litter Production Research Articles

Drought effects on litter fraction and recovery in a subtropical forest

Litter input is a critical link between the circulation and flows of energy and matter in forest ecosystems. Drought events impact litter inputs, affecting forest ecosystems’ nutrient and energy cycles. To investigate the response of litter production to extreme drought, explore their recovery mechanism, and the difference between whole year, concurrent drought, non-drought period, rainy season, and dry season. We studied an extreme drought event in a subtropical evergreen broadleaved forest in the Ailao Mountain in 2009–2010. We used 10 years (2005–2014) of monthly litter production and climate data, including monthly average precipitation (MAP), soil water content (SWC), and monthly average temperature (MAT). The observation period was separated into pre-drought (2005–2008), during-drought (2009–2010), and post-drought (2011–2014) periods. We found that annual total litter production decreased by 12 % during the drought (p < 0. 05), similar to that in the drought period. Leaf litter production increased by 1 % during drought time, and other fraction decreased obviously. The contribution of water environmental factors to litter production was more evident after drought events. MAT, MAP, and SWC jointly affect litter input under extreme drought conditions, and the dominant factor is related to litter fraction and drought periods. Water environmental factors (MAP & SWC) contributed to litter input after drought events, while MAT mainly affected litter input during the non-drought and rainy seasons. Due to the growth and nutritional strategies of each fraction, the recovery time is branch < leaf < flower & fruit < moss < bark. The results further reveal litter production response to drought events and the importance of water factors in recovery.

Response of tropical forest productivity to seasonal drought mediated by potassium and phosphorus availability

Tropical forest productivity is increasingly reported to be nutrient limited, which may affect its response to seasonal droughts. Yet experimental evidence on nutrient limitation from Afrotropical forests remains rare. We conducted an ecosystem-scale, full factorial nitrogen (N)–phosphorus (P)–potassium (K) addition experiment in a moist forest in Uganda to investigate nutrient controls on fine litter production and foliar chemistry. The eight factorial treatments were replicated four times in 32 plots of 40 × 40 m each. During the three-year nutrient additions, we found K and P limitations on leaf litter production, exhibiting strong links to ecosystem responses to seasonal drought. Specifically, leaf litterfall consistently decreased in dry seasons with K additions, whereas P additions caused a reduction only during prolonged drought in the first year. Leaf litterfall was not significantly affected by N additions. Furthermore, K additions delayed the timing of leaf litterfall peak, underscoring the crucial role of K in regulating stomatal aperture and signalling during water-stress conditions and suggesting a prolonged leaf lifespan. Foliar N increased with N and P additions whereas K was the most resorbed nutrient. We conclude that the productivity and resilience of tropical forests, particularly under drier conditions, may depend on terrestrial K and P availability.

Analysis of Mangrove Leaf Litter Decomposition Rate in Mangrove Ecosystem of Muara Pagatan, South Kalimantan

Mangroves are the dominant ecosystem in coastal areas and estuaries and one of the most productive ecosystems in the world. Mangroves are an essential component in a complex food chain and have the potential for the life of various marine and terrestrial biotas, microorganisms, and macroorganisms. The decomposition of mangrove leaf litter by fungal bacteria produces nutrient source that is beneficial for fish, shrimps, and crabs. This study discusses the production and decomposition rate of mangrove leaf litter in the mangrove ecosystem of Muara Pagatan, South Kalimantan. With transect and litter trap methods, litter production during the observation ranged from 218.51 - 858.28 g/m2/45day. Of the four types of mangroves found, the highest litter production was found in Rhizophora mucronata mangrove species at 858.28 g/m2/45day, followed by Bruguiera gymnorrhiza species at 268.52 g/m2/45day, and the lowest litter production was Avicennia marina mangrove species at 222.9 g/m2/45day and Sonneratia alba at 218.51 g/m2/45day. The remaining dry weight during observation ranged from 1.06 g - 2.46 g. In sum, the highest litter productivition and decomposition rate was found in Rhizophora species and litter was not completely decomposed after 45 days.

Production and Decomposition of Mangrove Species Rhizophora apiculata Blume in Surabaya East Coast Indonesia

The mangrove ecosystem is supported by the production and decomposition of leaf litter, as well as the release of nutrients into the environment and the neighbouring coastal seas. The release of phosphorus and nitrogen contributes significantly to the improvement of the nutritional values, which benefits marine species and the neighbourhood. In the current study, nutrient release, leaf decomposition rate, litter generation, and mangrove habitat at Surabaya East Coast, Java, Indonesia were all examined. Three transects and three plots in each transect were established. The percentage of initial dry mass remaining in the litter bags were determined by using two sample t-test in Statistica 6.0 software. The decomposition of Rhizophora apiculata leaves was studied by using litter bag technique. They were made of synthetic nylon with the dimension of 15×15×25 cm and mesh size of 1×1.25 mm2. Senescent leaves were used because they present major leaves on the forest floor. According to the findings, daily mangrove litter production (dry weight) varied between 2.15 and 3.28 g/m2. Branch litter (9.43 – 13.27%), reproductive parts (8.20 – 14, 31%), and leaf litter (76.26 – 78.53%) were the other major contributors. The 345.6 ha of mangrove forests along the east coast of Surabaya are the results of reforestation, which has the potential to produce nitrogen and phosphorus at the rates of 109.43 to 173.549 kg/ha/year and 5.467 to 8.12 kg/h/year, respectively. These results imply that decomposition breakdown rates differ across the research area due to the variation in the nutrients availability. Changes in the breakdown of detritus point to variations in nutrient intake, which is crucial for mangrove ecosystems.

Analysis of mangrove litter production and carbon stock in Sukamandi Village, Belitung Timur Regency

This study examined the litter production and carbon stock in the mangrove forest of Sukamandi Village in Belitung Timur Regency. The research identified 10 mangrove species in the area and found that the highest litter biomass was recorded at 6x10-8 ton/ha in station III. The organic material content varied across stations, with the highest value observed in station III. The carbon content of mangrove litter was relatively low due to its composition. The study emphasizes the significance of mangrove ecosystems in carbon sequestration and underscores the need for conservation efforts in Sukamandi Village. The variations in leaf litter production in the mangrove forest are influenced by factors such as mangrove density, plant age, and fertility. Leaf litter production is higher in areas with greater tree density and varies among different mangrove species. Natural factors like weather conditions, wind direction and speed, and movements of living organisms can also impact leaf litter production. The average leaf litter production rate in Sukamandi Village is 258.81 gr/m2/month or 8.62 gr/m2/day. The carbon content in mangrove leaf litter is relatively low due to its composition, which primarily consists of water and mineral nutrients.

Impacts of land use history on leaf litter input, chemical composition, decomposition and related nutrient cycling in young and old secondary tropical lowland rainforests (Sumatra, Indonesia)

BackgroundNutrient cycle in tropical forests is mainly driven by litter fall amounts and by litter decay due to litter physical and chemical properties. Apart from differences in site conditions, different successional stages of tropical rainforests may influence nutrient inputs to the soil via differences in litter fall and decay.MethodsWe studied leaf litter fall, decomposition and related nutrient input to the soil in two secondary tropical rainforest types differing in land-use intensity and history in the lowlands of Sumatra (Indonesia).ResultsMean annual litter fall was by 29.5% higher in the old than in the young secondary forests. In contrast, annual litter decomposition differed only marginally (54.9% vs. 52.1%) in young vs. old secondary forests. Litter chemical composition (C, N, P, K contents) did not differ between the forest types. Litter decomposition was also not different between the forest types (4.6% vs. 4.3% loss of initial weight per month). Consequently, annual nutrient input to the soil was primarily affected by differences in leaf litter production, thus, old secondary forests exceeded that of young secondary forests by 30% and 24% for C and N, but was not different regaring P and K among the two forest types.ConclusionsThe results indicate that litter nutrient inputs to the soil in the two types of secondary tropical lowland forests are most strongly influenced by aboveground litter production rather than litter chemical quality or litter decay. We conclude that the restoration status of secondary tropical lowland forests is crucial for the nutrient status of these forest ecosystems.

La descomposición de la hojarasca de Ochroma pyramidale (Malvaceae)

The tree Ochroma pyramidale is used to recover jungle areas that have been cultivated. This native species generates a thick layer of leaf litter that remains for several years. The objectives of this study were: 1) to know how much leaf litter is produced, 2) to estimate how long it persists in the soil, and 3) to identify the role of soil fauna in its decomposition. Leaf litter production was estimated at 11 Mg/ha/year, while over the course of 13 years the biomass and depth of the leaf litter layer measured in three sites previously planted with Ochroma showed a decrease of over 60%. In a leaf litter decomposition experiment, 37% of biomass was lost in 180 days. Soil mesofauna reduced the concentration of cellulose in leaf litter, while lignin decreased due to the time of permanence of the leaf litter in the soil. The high C:N proportion of the leaves, together with high lignin concentrations, could explain the low levels of loss and accumulation of biomass.

Leaf litter production and decomposition in a Riverine Mangrove forest in India

Leaf litter production and decomposition in a Riverine Mangrove forest in India

Long Term Seasonal Variability on Litterfall in Tropical Dry Forests, Western Thailand

Nutrient recycling is one of the most important services that supports other processes in ecosystems. Changing litterfall patterns induced by climate change can cause imbalances in nutrient availability. In this study, we reported the long-term (28-year) interplay between environmental factors and variability among litterfall fractions (leaves, flowers, and fruit) in a tropical dry forest located in Kanchanaburi, Thailand. A long-term litter trap dataset was collected and analyzed by lagged generalized additive models. Strong seasonality was observed among the litter fractions. The greatest leaf and flower litterfall accumulated mostly during the cool, dry season, while fruit litterfall occurred mostly during the rainy season. For leaf litter, significant deviations in maximum temperature (Tmax), volumetric soil moisture content (SM), and evapotranspiration (ET) during the months prior to the current litterfall month were the most plausible factors affecting leaf litter production. Vapor pressure deficit (VPD) and ET were isolated as the most significant factors affecting flower litterfall. Interestingly, light, mean temperature (Tmean), and the southern oscillation index (SOI) were the most significant factors affecting fruit litterfall, and wetter years proved to be highly correlated with elevated fruit litterfall. Such environmental variability affects both the triggering of litterfall and its quantity. Shifting environmental conditions can therefore alter nutrient recycling rates through the changing characteristics and quantity of litter.

The transition of sokshing (leaf litter forest) property rights and management: A case study of Punakha and Wangdue district, Bhutan

Prior to the government's involvement, the local communities had customary rights over the forest including access to, use of, and management of forest resources in Bhutan. However, the fate of customary rights changed with the provision of new governance. A case of sokshing (leaflitter forest) and its management under new regulations are discussed in this study. The sokshing which was de facto independent and owned by private households and communities, was nationalized under the provision of the Forest Act of 1969. Subsequently, the Land Act of 1978 permitted the use of sokshing for the collection of leaf litter and fodder, restraining the use of standing trees and land. However, with the Land Act of 2007, the user right was abolished and sokshing was completely nationalized and deregistered from lagthram (private land registration record), infringing the people's customary rights. This study examined how an individuals responded to changes in the legal ownership of sokshing and its effect on the sustainability, management, and preservation of sokshing land. To achieve this, 61 households comprising both sokshing and non-sokshing owners were interviewed using a semi-structured questionnaire. Ostrom and Schlager's bundles of rights framework were used to examine the changes in the forest property rights of local people. The results revealed that despite the enactment of the 2007 land act, the majority of respondents continued to manage and use sokshing for the production of leaf litter. However, there were concerns among local people about the ownership of their sokshing land due to poor implementation of the land act and lack of clarity on land property rights. Therefore, to address the concerns and ensure the sustainable management and utilization of sokshing land, it is recommended that the Land Act of 2007 be amended to include provisions for thorough consultation and participation, the development of a comprehensive management plan, and the promotion of equity in the use and management of sokshing resources.

Salinity exposure affects lower-canopy specific leaf area of upland trees in a coastal deciduous forest

Sea level rise and increasing storm surges are likely to affect the canopy physiology, ecology, and structure of coastal forests, even well in advance of tree mortality. Laboratory and greenhouse studies have documented that saltwater exposure can trigger changes in leaf-level physiology and morphology, but few in situ studies have examined how tree-specific leaf area (SLA), the ratio of leaf area to mass and a crucial trait and model parameter, is affected by saline soils. We conducted an observational study of SLA in a mid-Atlantic (USA) coastal deciduous forest, taking advantage of a natural gradient in salinity along a tidal creek. Measured SLA of the 239 trees and seven species sampled ranged from Carya glabra (N = 6 trees, mean SLA = 277.9 ± 36.3 cm2/g) to Fagus grandifolia (N = 60, 321.9 ± 62.9 cm2/g); as expected, trees species and canopy position (sun versus shade) significantly affected SLA. For trees (N = 100) directly exposed to the tidal creek, salinity was highly significant after accounting for species (P < 0.001), with trees in the lower reaches of the creek having lower SLA. Leaf area index (LAI), computed from SLA and litter traps, ranged from 4.8 to 15.8 and was inversely related to salinity exposure; the spatial variability in leaf litter production contributed much more to LAI uncertainty than did SLA variability. These in situ results are correlative but consistent with the hypothesis, based on previous greenhouse studies, that the stress of chronic salinity exposure changes species’ leaf morphology. Our findings are useful for understanding the growing effects of saltwater intrusion into upland forests, as well as parameterizing and testing ecosystem-scale models simulating forest stressors and disturbances at the terrestrial-aquatic interface.

Divergent Decomposition Patterns of Leaf Litter and Fine Roots from an Urban Forest in Mid-Subtropical China

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

Pattern of Litterfall Production Throughout a Tropical Humid Forest Chronosequence

Neotropical landscapes are often characterized as mosaics of actively grazed pastures and forest fragments at various stages of succession. Restoring abandoned pastures requires intervening with actions informed by local ecological succession. Here we evaluate how litter production, a key component of nutrient cycling in forests, varies between physiographic landscapes (hill and lowland mountain), among stand age groups (early-secondary: 0–20 year, intermediate-secondary: 20–40 year, and old-growth forests: > 40 year), and in response to climatic (precipitation and irradiation) and forest structure and biodiversity variables (stand density, basal area, species density, diversity), in a tropical humid forest chronosequence. Total and leaf litter production was higher in the lower elevation hill landscape. Leaf litter production increased with stand age in both landscapes but only correlated positively with forest structure and biodiversity in the hill landscape. Lack of correlation in the mountain landscape is attributed to greater variance in structure and species composition in the subset of plots selected from this landscape for this study. Both landscapes exhibited an asynchronous, bimodal regime of leaf fall in response to precipitation. Leaf litter peaks prior to the wet season likely occur in response to water stress, while peaks after the wet season that coincided with increasing solar irradiation are likely the result of a leaf turnover strategy to optimize photosynthesis. Ecological succession in these landscapes does not appear limited in leaf litter production, but further research on the drivers of leaf litter production recovery is necessary to adequately guide intervention efforts.

Tree height, canopy cover, and leaf litter production of Rhizophora apiculata in Baganga, Davao Oriental, Philippines

Tree height, canopy cover, and leaf litter production of Rhizophora apiculata in Baganga, Davao Oriental, Philippines

Herbivory in southeastern Brazilian mangroves: An analysis of 11 years of litterfall monitoring

Severe defoliation of mangrove species is reported in several parts of the world. We analyzed the effect of a severe defoliation event resulting from the attack of a lepidopteran caterpillar (an insect outbreak) on the litterfall production. The attack occurred between 2009 and 2010 in a mangrove in southeastern Brazil. Leaf litter production by different mangrove species between 2008 and 2019, was considered in the analysis. The infestation directly affected the species Avicennia schaueriana Stapf & Leechm in all physiographic types assessed, with a decrease in leaf litter production between 43% and 86% since the monitoring began (2009) until the year when defoliation reached the maximum (2011). A decrease in the impact of defoliation was observed along the tidal flooding gradient, with more pronounced effects in forests located in the transition zone with the salt-flat, and progressive decrease towards fringe forests. In fringe and basin forests, leaf litter production by Laguncularia racemosa (L.) decreased between 52% and 67% between 2009 and 2011, respectively, and increased 30% in transition forests. Contrarily, the contribution of Rhizophora mangle (L.) increased 7% in basin, became noticeable in transition, and decreased by 25% in the fringe forests. The time required for A. schaueriana to recover the level of debris production was 8 years, and still reflect the effect of the severe, selective defoliation process on the dynamics and ecological succession of mangrove forests. A model that determines the stages of defoliation and their direct and indirect impacts on litter was developed.

Perceptions of landlords to trees in built-up Urban areas in Ghana

ABSTRACT For effective deployment of trees as green infrastructure in major cities, it is imperative to understand landlords’ perceptions of trees in built-up ecosystems. Six hundred landlords were systematically sampled from three major cities in Ghana. A questionnaire was used to elicit information about landlords’ perceptions of trees in built-up urban areas. The data generated were analysed using descriptive statistics, Cronbach Alpha, and Kendall Coefficient of Concordance. The results indicated that the most important ecosystem services perceived with the highest positive relevance to the landlords are the provision of edible fruits and nuts, improved health conditions, shade, oxygen production, and wind protection by trees in urban areas. Whilst perceived negative functions of trees include structural damage of roots to buildings and pavements, and hosts to insects and pests. The production of leaf litter and slippery fruits are considered to be a nuisance by the landlords.

Effects of Two Management Practices on Monthly Litterfall in a Cypress Plantation

Optimizing stand structure can enhance plantation forest ecosystem service functions by regulating litterfall patterns; however, the effects of close-to-nature management on litterfall production remain unclear. Here, we selected three cypress (Cupressus funebris) plantations, including one using the practice of strip filling (SF), one using the practice of ecological thinning (ET), and one pure cypress plantation without any artificial interference. The production of total litterfall and its components (leaf, twig, reproductive organ and miscellaneous litterfall) were investigated monthly over one year from September 2019 to August 2020. Compared with that of the pure plantation, the total annual litterfall production of the SF and ET plantations decreased significantly by 10.8% and 36.44%, respectively. The annual production of leaf and reproductive organ litter was similar to that of total litterfall, but that of twig and miscellaneous litter was higher in the SF and ET plantations than in the pure plantation. Moreover, total, leaf and reproductive organ litterfall production displayed unimodal dynamics regardless of plantation, although the peaks of reproductive organ litter production occurred in different months. In contrast, the production of twig litter showed bimodal dynamics in the pure plantation, while unimodal and irregular dynamics were observed in the plantations with ET and SF, respectively. Additionally, insignificant differences in the isometric growth index of leaf litter and total litterfall were observed. The allometric indices of twig litterfall versus total litterfall, reproductive organ litterfall versus total litterfall, and leaf litterfall versus twig litterfall were higher in the plantations with SF and ET than in the pure plantation. Redundancy analysis (RDA) revealed that diameter at breast height and air temperature were the most important factors shaping the annual and monthly production of litterfall, respectively. These results provide efficient data to support the rectification of the material circulation of cypress plantations and their future management.

Litter quality and decomposition responses to drought in a northeastern US deciduous forest

Even though drought impacts on tree physiology have been identified, whether drought affects leaf litter chemistry that, in turn, influences litter decay rates is still poorly understood. We compared litter quality and decomposition for two cohorts of leaves from five co-occurring seasonally deciduous tree species: Acer saccharum, Tilia americana, Quercus rubra, Quercus alba, and Ostrya virginiana. One cohort experienced a growing-season drought, and the other cohortcame from the same trees in the ensuing, post-drought growing season. Leaf litter production was greater for drought litter than post-drought litter for all five species. Specific leaf area and nitrogen concentrations were 20% greater for the drought cohort than the post-drought cohort. Concentrations of non-structural carbohydrates were about 14% greater for the drought cohort, except for greater values for post-drought A. saccharum litter. Pectin in the middle lamella of leaf litter was 31% lower for the drought cohort compared to post-drought cohort. We found few differences in litter decay rates between drought and post-drought cohorts, although Q. rubra litter had more decomposition for the post-drought cohort than the drought cohort, whereas A. saccharum litter had more decomposition for the drought cohort than the post-drought cohort. Leaf litter decay rates for the drought cohort were related to litter nitrogen and lignin concentrations, whereas decay rates for the post-drought cohort were related to litter carbohydrate concentrations. Our findings suggest that the role of drought events on seasonally deciduous forest ecosystems must recognize species-specific, idiosyncratic responses in leaf litter quality and decomposition.

NUTRIENT DYNAMICS IN SOIL ASSOCIATED WITH LEAF LITTER OF Shorea robusta Gaertn. f. IN MADHUPUR SAL FOREST OF BANGLADESH

Litter plays an important role in nutrient cycling in forest ecosystem. Nutrients are released from litter through leaching, and decomposition process and readily available nutrients are obtained through leaching process. Shorea robusta forest is a tropical deciduous forest and shed their leaves during the dry season. In the vicinity, poor people usually collect this litter from the forest to meet household demand for fuel. Thus, a considerable amount of nutrients is lost from this system.However, some nutrients from those leaves is possible to harvest through leaching technique before use as fuel. Therefore, to quantify this nutrient Leaf litter production and leaf litter standing crop were estimated in the Modhupur Sal forest. In addition, mass loss and nutrients (nitrogen, potassium and phosphorus) release through leaching were observed over 192 hours through leaching process in the laboratory. Mean leaf litter production was found 12.94 ± 0.65 g/m2/day during the litter shedding period was estimated to and the mean leaf litter standing crop was found 89.20 ± 9.77g/m2. About 10% of initial mass was lost after 48 hours of leaching process. Moreover, initial concentration of nitrogen and phosphorus was sharply decreased to 65 µg/g and 42 µg/g respectively after 24 hours and initial concentration (38 µg/g) of potassium was sharply decreased to 5 µg/g after 12 hours. About 25%, 45% and 92% of initial N, P and K content, respectively can be extracted through leaching process.

Fine Litter Dynamics in Tropical Dry Forests Located in Two Contrasting Landscapes of the Colombian Caribbean

Tropical dry forests (TDFs) represent 42% of all tropical forests; they are extensive, but little is known of their structure and function. The fine litterfall represents the main route of circulation of organic materials and nutrients in these ecosystems. The objective of this study was to compare several remnants of TDFs located in contrasting landscape units—Mountain and Lomerio—and with different precipitation, in terms of the fluxes of organic materials to the soil, derived from the production of fine litterfall from the canopy. The fine litterfall (including woody material up to 2 cm in diameter) was collected monthly from April 2020 to March 2021, in 29 circular plots of 500 m2 randomly established. High rates of litterfall were recorded in the Lomerio landscape (4.9 Mg ha−1) than in the Mountain landscape (4.5 Mg ha−1). The monthly leaf litter production showed clear seasonal patterns, which were largely driven by the importance of the species in the landscape and the effect of precipitation during the study. Annual fine litter production observed in this study in comparison with other TDFs indicates relevant productivity levels, which contribute to the activation of biogeochemical cycles and improved ecosystem functionality.