Search Results (45)

Modern pollen deposition studies are essential to forestry and palaeoecological research, as they provide the key to understanding the relationship between the abundance of palynomorphs in natural (moss, litter, top core sediment) or artificial traps and the surrounding vegetation cover. In 1996, the EPMP (European Pollen Monitoring Programme) laid the foundations for pollen monitoring research in Europe, involving several countries and dozens of researchers in placing “Tauber-style” artificial traps across a wide range of ecosystems, and legitimising the collection of mosses for comparative studies. Here, we propose a straightforward, fast, and effective procedure—developed within the ALIVE “TrAcking Long-term declIne of forest biodiVErsity in Italy to support conservation actions” Project—for the collection of moss polsters and vegetation data, aimed at monitoring modern pollen deposition at the national scale. This protocol addresses a gap in existing literature, as no shared fieldwork guidelines are currently available. We demonstrate how the spatial pattern of modern pollen deposition can be investigated using two of the ALIVE Project’s target taxa (Fagus and evergreen Quercus) to explore the potential of microbotanical data in reflecting the current distribution of forest tree taxa at a national scale. The data collected within the ALIVE Project provide a synoptic picture of pollen deposition across Italy’s highly diversified landscapes and allow for preliminary considerations on the relationships between pollen deposition and modern vegetation cover of forest taxa. Full article

We studied differences in the decomposition rate between Pinus merkusii Jungh. et de Vriese (tusam) leaves, a representative of needle leaf litter, and Diospyros celebica Bakh. (ebony) leaves, a representative of broadleaf litter, in three forest communities (Karst, Lowland, Pine) on the island of Sulawesi, Indonesia, and identified their determinants. Twenty-four 1 m × 1 m quadrats were set up in each forest community to observe the in situ decomposition process. Near each quadrat, 1 m² litter traps were set to monitor litter production. In addition, 30 litter bags containing tusam leaves and 30 litter bags containing ebony leaves were spread in the three forest communities, in both the dry and wet seasons, to observe their decomposition rate during each season. The ANOVA test showed that the one-year in situ Decomposition Rate Constant (k) was significantly highest in the Karst forest (0.0921/year), followed by the Lowland forest (0.0700/year), and the lowest in the Pine forest (0.0277/year). During the dry season, the mean k-value of tusam leaves was significantly faster than ebony leaves in Karst (0.7162/6 months for tusam, 0.3840/6 months for ebony) and Lowland forests (0.3472/6 months for tusam, 0.1017/6 months for ebony), but on the contrary, it is slower in the Pine forest (0.0498/6 months for tusam, 0.0745/6 months for ebony). During the wet season, there was no significant difference between the mean k-value of tusam leaves compared to ebony leaves in the Karst (0.5217/4 months for tusam, 0.4859/4 months for ebony) and Lowland (0.2397/4 months for tusam, 0.2098/4 months for ebony) forests, but in the Pine forest, the mean k-value of ebony leaves was significantly higher than that of tusam leaves (0.0942/4 months for tusam, 0.1650/4 months for ebony). This study explains that the decomposition process of leaf litter is complex, species-specific, and is controlled by a combination of factors. Extrinsic factors play a more critical role than intrinsic factors in determining the k-value. The low rate of decomposition of tusam leaves under its mother tree stands is not caused by intrinsic factors, but rather by extrinsic factors that inhibit the growth of decomposing agents. Full article

Litter and pruning biomass are integral to nutrient cycling in the plant–soil ecosystem, contributing significantly to organic matter formation and humus development through decomposition and nutrient mineralization, which ultimately influence soil fertility and health. However, the litterfall dynamics in mango orchards are not well understood, and its contribution to nutrient cycling has seldom been measured. This study aimed to estimate litterfall and pruning biomass in mango orchards and assess the nutrient contents of various biomass components. Litter and pruning biomass samples were collected from four commercial mango orchards planted with Kensington Pride (‘KP’) and ‘B74’ (‘Calypso^®’) cultivars in the Darwin and Katherine regions, using litter traps placed on the orchard floors. Samples were sorted (leaves, flowers, panicles, fruits, and branches) and analyzed for nutrient contents. Results showed that most biomass abscissions occurred between late June and August, spanning approximately 100 days involving floral induction phase, fruit set, and maturity. Leaves made up most of the abscised litter biomass, while branches were the primary component of pruning biomass. The overall ranking of biomass across both regions and orchards is as follows: leaves > branches > panicles > flowers > fruits. The carbon–nitrogen (C:N) ratio of litter pruning material ranged from 30 (flowers) to 139 (branches). On a hectare basis, litter and biomass inputs contained 1.2 t carbon (C), 21.2 kg nitrogen (N), 0.80 kg phosphorus (P), 4.9 kg potassium (K), 8.7 kg calcium (Ca), 2.0 kg magnesium (Mg), 1.1 kg sulfur (S), 15 g boron (B), 13.6 g copper (Cu), 99.3 g iron (Fe), 78.6 g manganese (Mn), and 28.6 g zinc (Zn). The results indicate that annual litterfall may contribute substantially to plant nutrient supply and soil health when incorporated into the soil to undergo decomposition. This study contributes to a better understanding of litter biomass, nutrient sources, and nutrient cycling in tropical mango production systems, offering insights that support accurate nutrient budgeting and help prevent over-fertilization. However, further research is needed to examine biomass accumulation under different pruning regimes, decomposition dynamics, microbial interactions, and broader ecological effects to understand litterfall’s role in promoting plant growth, enhancing soil health, and supporting sustainable mango production. Full article

The transformation of the Cerrado biome into areas with different levels of activity and anthropic pressure negatively impacts biodiversity. This study evaluated the response of the dung beetle community to changes in land use systems: forests, rubber trees, pastures, and soybeans. Five areas were sampled in each system with a minimum distance of 2 km between them. Dung beetles were collected using pitfall traps, and both local (vegetation density, basal area of wooded vegetation, fractal dimension, litter height, electrical conductance (mV), water content in the soil (%), and soil resistance (kPa)) and landscape-related environmental variables (land use and overall composition and configuration of the landscape surrounding the sampling areas) were measured. In total, 2294 specimens were collected and distributed among 34 species and 18 genera. There was no significant difference in abundance between the systems, but differences in the number of species and biomass were observed between forest and soybean systems, as well as a separation of communities between the tree-covered (forest and rubber tree) and open (pasture and soybean) systems. Density and arboreal basal area were the main predictive variables for the diversity of the dung beetle community, reinforcing the importance of vegetation cover for maintaining diversity, whereas local and landscape-related variables influenced community composition. Full article

La Graciosa, a Natura 2000 site in the Canary Islands, faces substantial conservation challenges, including a large free-roaming cat population that threatens the island’s native biodiversity. In July 2024, a Trap–Neuter–Return (TNR) campaign achieved an 81.4% sterilization rate within urban areas, highlighting TNR’s short-term effectiveness in reducing reproductive potential and, consequently, mitigating predation pressures primarily through the prevention of new litters and reduced reproductive activity in cats. The campaign’s success relied heavily on the active involvement of the local community, who assisted with identifying, trapping, and monitoring free-roaming cats, thereby facilitating a high sterilization rate. However, administrative restrictions hindered access to peri-urban zones, leaving essential population clusters unsterilized and limiting the campaign’s overall scope. Additionally, strong opposition from conservation groups, amplified by extensive media coverage, halted the project prematurely, reducing the effective sterilization rate to 69.3% within three months. Population Viability Analysis (PVA) suggests that achieving high sterilization rates could lead to population reduction over time; however, the inability to access all population segments and to reach the ideal 93–95% sterilization threshold limits TNR’s potential as a long-term standalone solution. Our findings underscore the need for adaptive, context-specific management frameworks in ecologically sensitive areas that integrate TNR with complementary measures, consider regulatory barriers, and value community involvement. This case study provides crucial insights for policymakers and conservationists seeking to balance biodiversity conservation with humane management practices in protected areas. Full article

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. Full article

This study investigated the impact of thinning and felled logs (random- and contour-felled logs) on overland flow, soil erosion, and litter erosion in a Japanese cypress forest plantation (2400 tree ha⁻¹) with low ground cover, from 2018 to 2023 in central Japan. Monthly measurements of overland flow and soil and litter erosion were carried out using small-sized traps across three plots (two treatments and one control). In early 2020, a 40% thinning (tree ha⁻¹) was conducted in the two treatment plots. Overland flow increased in the plot with random-felled logs during the first year post-thinning (from 139.1 to 422.0 L m⁻¹), while it remained stable in the plot with contour-felled logs (from 341.8 to 337.1 L m⁻¹). A paired-plot analysis showed no change in overland flow in the contour-felled logs plot compared to the control plot from the pre- to post-thinning periods (pre-thinning Y = 0.41X − 0.69, post-thinning Y = 0.5X + 5.46, ANCOVA: p > 0.05). However, exposure to direct rainfall on uncovered ground areas post-thinning led to increased soil and litter erosion in both treatment plots. These findings suggest that thinning combined with contour-felled logs effectively stabilizes overland flow. Therefore, thinning with contour-felled logs can be considered a viable method for mitigating overland flow in monoculture plantations with low ground cover. Full article

Historical sheep farming in the Patagonian drylands has led to reduced grass cover, soil erosion, and shrub encroachment, compromising ecosystem function. Effective restoration requires managing shrub cover, bare soil, and patch connectivity through various strategies. This study evaluates rehabilitation interventions in a grass-steppe ecosystem, comparing grazed and ungrazed areas. Over three years, we tested the following: (a) mechanical shrub cutting with biomass redistribution, and (b) enhancing patch connectivity with Pinus spp. branch piles, alongside controls, in eighteen 5 m × 5 m plots invaded by Mulinum spinosum. Half of the plots were fenced to exclude grazing, resulting in six treatment combinations. We monitored soil properties, vegetation cover, and species composition. The treatments explained twice as much of the variation in community composition as the annual climatic variations (0.26 vs. 0.13). Livestock exclusion increased perennial grass cover more than the grazed plots did (2.14 vs. 1.42 times the initial measure). All treatments reduced the amount of bare soil except the grazed controls. Shrub cutting, especially with grazing, increased the lasting litter coverage by 5–10% and decreased the bare soil equivalently. Organic matter increased except in the non-intervened interpatches (0.95 times). The enclosures with cut shrubs trapped erodible particles, showing a 5% increase. Our study highlights that grazing destabilizes communities, while enclosures stabilize them, with interventions improving soil fertility and mitigating erosion. Full article

Soil erosion and hydrogeological risk are critical phenomena gaining increased recognition within the scientific community. Although these occurrences are naturally occurring, human activities can exacerbate their impacts. For example, deforestation consistently amplifies soil erosion. This study examines two distinct forest management strategies aimed at addressing soil erosion: the Banded Standards Method (BSM) and the Scattered Standards Method (SSM). We conducted a field experiment in two test areas located in central Italy, with one area employing the BSM and the other implementing the SSM. Two soil erosion plots were established, representing prototypes of a novel erosion monitoring apparatus called the Natural Erosion Trap (NET), or Diabrosimeter, specifically designed for forest environments. At regular intervals, particularly after significant storm events, sediment and leaf litter accumulated within the erosion plots were collected, dried, and weighed to quantify erosion rates and assess the efficacy of the silvicultural methods under investigation. The results revealed a 30.72% reduction in the eroded material with BSM compared to SSM, underscoring BSM’s ability to mitigate potential hazards and preserve environmental integrity. Full article

The Tisza River is the longest tributary of the Danube, draining the eastern part of the Carpathian Basin (Central Europe). Five countries share its catchment with different waste production and management practices. Large amounts of waste, including macroplastics (MaPs), are washed into the river. Some of the litter is trapped by the riparian vegetation forming litter accumulations. The study aimed to map the amount of litter by a citizen science program and remote sensing data and to compare the MaP data to the amount of microplastic fragments in sediments. Volunteers reported 3216 riverine litter accumulations from five countries along the entire length of the Tisza (2016–2022). The results suggest that low flow conditions (e.g., impoundment by dams) support litter and MaP trapping. The volume of large accumulations registered by the citizens showed a good correlation with the area of drifting litter revealed on Sentinel-2 images (2016–2022) using machine learning algorithms. Though the MaPs probably fragmentate during their fluvial transport, no clear connection was found between the volume of litter accumulations and the mean microplastic fragment content of sediments (2019–2022). The “Clean Tisza Map“ reveals the high degree of stranded pollutants along rivers and supports public cleanup activities. Full article

This study sought to investigate the vertical distribution pattern of the soil faunal community in a low-altitude mountain area. On 8 July 2022, a low hill was selected as the study area, and soil arthropods were collected through traps. The leaf litter, vegetation type, and distribution quantity of each sampling site were investigated while the soil faunae were collected. In addition, the soil’s physical and chemical parameters were measured. The results of a one-way ANOVA showed that there were significant differences (p < 0.05) in the soil properties, leaf litter, and plant quantities at different altitudes within the research area. A total of 1086 soil arthropods, belonging to five classes and ten orders, were collected during the study period. The dominant species of soil arthropods at different altitudes were significantly different. The dominant species in low-altitude areas were Armadillidium sp. and Aethus nigritus. However, Eupolyphaga sinensis and Philodromidae were the dominant species in high-altitude areas. The results of a non-metric multidimensional scaling (NMDS) analysis showed that the soil faunae at different altitudes were clustered into two communities: a high-altitude community and a low-altitude community. With the increase in altitude, the species richness of the soil arthropods gradually decreased, and their abundance showed a decreasing trend. A redundancy analysis (RDA) of the soil arthropods and environmental factors showed that soil moisture (p < 0.01), pH (p < 0.01) and defoliation (p < 0.05) had significant effects on the distribution of the soil fauna. The results of a Pearson correlation analysis indicated that different environmental factors had interactive effects on the distribution of the soil arthropods. The quantity and species richness of the soil arthropods in different sample lines were tested using a variance analysis. The results showed that there were significantly smaller quantities of soil arthropods in the sampling line closer to the trekking ladder. This indicates that human tourism, namely mountaineering activities, had a direct impact on the soil fauna. This study can provide a reference for and data support in the development of biodiversity conservation measures for forest parks in low mountain areas. Full article

This study presents results from an experimental campaign to explore how different riparian zone characteristics may facilitate the transport or capturing of plastics floating through the fluvial system. Specifically, following field observations for the transport of plastics through fluvial vectors, a substantial number of flume experiments has been designed to assess the effect of floating macro-plastics and riparian zone characteristics. The results from flume experiments were analyzed using particle tracking velocimetry techniques to derive transport metrics (such as transport velocities) of macro-plastics of different sizes and shapes, released at five locations across a wide channel with distinct distance from the vegetated riverbank. The findings are discussed while considering the trapping mechanisms along the vegetated riverbank, which include a range of vegetation densities and arrangements, aiming to identify and quantify the degree of impact of each of the control parameters on the transport of floating plastics. The flow velocimetry records obtained at locations near and within the riverbank correlate well with the transport velocities of the floating plastics. Macro-plastic litter carried downstream away from the riverbank can have up to nine times the transport velocity, compared to those found within the riverbank. The change from a low to a high average density can result in about three times decrease in the transport velocity of floating macro-plastic litter within the riparian zone. These outcomes can help inform better practices for the management of riparian vegetation to maximize the trapping efficiency of macro-plastics, adapted to different flow conditions and river morphologies. Full article

Every year, harbor and sailing festivals attract close to 20 million visitors in the Baltic Sea region, but their consequences on marine litter pollution are still unknown. We combine field studies with model simulations and literature reviews to quantify the annual emissions of floating macro-litter and to assess its retention in estuaries and role in Baltic Sea pollution. Results focusing on Hanse Sail in Rostock and Kiel Week are extrapolated to the entire Baltic Sea region. After the Hanse Sail 2018, the harbor pollution amounted to about 950 floating macro-litter particles/km²; 85–90% were plastics. We calculated an emission between 0.24 and 3 particles per 1000 visitors, depending on the year and the waste management system. About 0.02% of all waste generated during a festival ends up in the harbor water. The Hanse Sails contributes less than 1% to the total annual macro-litter emissions in the Warnow estuary. Model simulations indicate that over 99% of the emitted litter is trapped in the estuary. Therefore, Hanse Sails are not relevant to Baltic Sea pollution. The extrapolated Baltic-Sea-wide annual emissions are between 4466 and (more likely) 55,830 macro-litter particles. The over-30 harbor and sailing festivals contribute an estimated <0.05% to the total annual macro-litter emissions in the Baltic Sea region. Full article

Landscape complexity is a crucial factor for insect diversity in agricultural landscapes. Short-rotation coppices (SRCs) are characterised by high habitat heterogeneity. The impact of vegetation structure on the composition and diversity of ground beetle and arachnid communities was therefore investigated in four SRCs and six reference plots. The study site was located in Hesse, Germany. The invertebrates were surveyed from 2011 to 2014 using pitfall traps, and the vegetation structure was quantified by estimating the percentage cover of 10 structural variables. The impact of the selected structural variables on community composition was analysed during grove growth as well as after a timber harvest. We found correlations between the cover percentages of structural variables and the quantitative and qualitative species composition in both animal groups (p ≤ 0.05). The share of individuals of forest species increased with rising shading and litter cover, while those of open land decreased. The opposite trends were found the year after the timber harvest. The SRCs showed a higher structural diversity compared to the reference biotopes (p ≤ 0.05). This was positively correlated (p ≤ 0.001) with species diversity and the variety of habitat preference groups in both animal groups. The high diversity within the habitat preference groups indicated a functional redundancy among species for both animal groups and, consequently, a high level of resilience within these communities. Little is known about the functional aspects of ground beetles and spiders in ecosystems, and detailed studies are urgently needed. We conclude that SRCs can contribute to the diversification of agricultural landscapes as an alternative to traditional crop cultivation. Full article

Coast redwoods (Sequoia sempervirens) are long-lived trees that create deep shade and litter layers, and have limited recruitment from seedlings. Botrytis cinerea is an airborne fungal pathogen that attacks redwood seedlings. B. cinerea lives as a saprotroph in dead plant matter or as a necrotroph in live tissue. In the coast redwood forest, accumulated leaf litter may provide inoculum for subsequent infections, limiting redwood seedling recruitment. Here, we examine the response of B. cinerea to fire in the coast redwood forest. We measured the abundance of airborne B. cinerea spores in paired burned and unburned plots using a selective and diagnostic medium. In a greenhouse experiment, we grew seedlings in four different treatments: (1) burned soil with no leaf litter, (2) unburned soil with no leaf litter, (3) burned soil with leaf litter collected from the burn plot, (4) unburned soil with leaf litter collected from the unburned plot. Spore trapping showed no difference in the abundance of airborne spores in the paired plots. The seedling experiment showed that disease was greatest and survival lowest when grown in burned soil; leaf litter collected from burned plots reduced survival while leaf litter from not-burned plots increased survival. These results indicate that fire did not affect airborne B. cinerea and post-fire conditions did not provide favorable growth conditions for coast redwood seedlings. Full article