Mixed Vegetation Research Articles

Land surface phenology for the characterization of Mediterranean permanent grasslands

The provision of ecosystem services from Mediterranean permanent grasslands is threatened due to shifting management practices and environmental pressures. This observational study tested the hypothesis that Land Surface Phenology (LSP) parameters from high-resolution satellite data can characterize various permanent grasslands to support conservation and improvement practices. The potential of LSP derived from Sentinel-2 data in identifying the multi-layer mixed vegetation of Mediterranean grasslands, including silvopastoral systems, that were well-characterized from an agronomic and ecological perspective through field surveys, was assessed. Forty-nine polygons, representing eleven sites characterized by different grassland vegetation, soil, climate and management, were identified in Sardinia (Italy). Sentinel-2 satellite images from 2017 to 2023 were processed to derive NDVI, and LSP parameters were calculated using TIMESAT 3.3 software. The Canonical Correspondence Analysis showed a significant association (p < 0.05) between a combination of LSP metrics used as proxies of a set of relevant agronomical indicators. It was then possible to differentiate managed vs. abandoned grasslands (e.g., start and peak of the season significantly later under unmanaged grasslands, p < 0.0001), wooded grasslands vs. open grasslands(e.g., base value significantly higher in woodlands and wooded grasslands, p < 0.0001) across environmental gradients (altitude) and management practices (green-down rate significantly higher under mown than unmown areas, p < 0.0001). The LSP parameters proved to be promising proxies to characterize agronomic features (e.g., length of the growing season, earliness, forage availability, mowing and grazing intensity, unpalatable species) of Mediterranean permanent grasslands. The characterization can support management design or monitoring to detect abandonment or environmental pressures early.

Features of Consistent Powassan Virus Lineage II Focus in Southern Maine, United States.

Powassan virus lineage II or deer tick virus (DTV) is a rare but increasingly reported human infection in the United States transmitted by Ixodes scapularis ticks. The virus is thought to be maintained in environmental foci that are optimal for tick and vertebrate reservoirs, but details on DTV ecology are poorly understood. We investigated DTV tick infection rates and reservoir host abundance in a focus of consistent DTV activity in Maine, USA. Host and tick abundance, vegetation, and microclimate conditions were measured in three forest sites representing increasing invasive understory infestation. Sites were selected representing native understory, mixed vegetation with some invasive Japanese barberry (Berberis thunbergii), and a highly invasive site dominated by Japanese barberry. Japanese barberry in the mixed vegetation site averaged 1 m in height with space between plants, whereas the highly invasive site had impenetrable Japanese barberry over 1.5 m. The DTV infection rate was greater in the highly invasive site. Density of I. scapularis ticks were significantly lower in the native forest site, and no DTV was found. Another feature of the DTV focus was more stable humid microclimate throughout the year compared with the other sites and a nearby continuous section of forest, consistent with reports from Connecticut, USA. We conclude that invasive Japanese barberry stands provide favorable and consistent microclimate conditions to maintain high DTV infection rates annually among questing I. scapularis ticks. Understanding environmental and landscape features that support high infection rates could lead to the identification of high-risk habitats for contracting DTV.

Impact of crop type on the greenhouse gas (GHG) emissions of a rewetted cultivated peatland

Abstract. Raising the water table is an effective way to abate greenhouse gas emissions from cultivated peat soils. We experimented a gradual water table rise at a highly degraded agricultural peat soil site with plots of willow, forage and mixed vegetation (set-aside) in southern Finland. We measured the emissions of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) for 4 years. The mean annual groundwater table depth was about 54, 40, 40 and 30 cm in 2019–2022, respectively. The results indicated that a 10 cm rise in the water table depth was able to slow down annual CO2 emissions from soil respiration by 0.87 Mg CO2-C ha−1. CH4 fluxes changed from uptake to emissions with a rise in the water table depth, and the maximum mean annual emission rate was 11 kg CH4-C ha−1. Nitrous oxide emissions ranged from 2 to 33 kg N2O-N ha−1 yr−1; they were high in bare soil at the beginning of the experiment but decreased towards the end of the experiment. Short rotation cropping of willow reached net sequestration of carbon before harvest, but all treatments and years showed a net loss of carbon based on the net ecosystem carbon balance. Overall, the short rotation coppice of willow had the most favourable carbon and greenhouse gas balance over the years (10 Mg CO2 eq. on average over 4 years). The total greenhouse gas balance of the forage and set-aside treatments did not go under 27 Mg CO2 eq. ha−1 yr−1, highlighting the challenge in curbing peat decomposition in highly degraded cultivated peatlands.

Soil Ecosystem Services in Urban Parks as a Basis for Better Urban Planning: The Case of Mexico City

Until now, the contribution of soils in urban spaces has been underestimated and, as a result, the services they provide have been severely undervalued in urban planning. This article aims to address this issue through a study of Chapultepec Park in Mexico City. We provide two methodological proposals for the analysis of soil ecosystem services characterized by the interaction of natural and anthropic processes: the morpho-pedological landscapes (MpL), in which we quantify soil carbon sequestration (SOC Mg ha−1) and the comparison of two methods for the analysis of hydraulic conductivity: Pedotransfer functions (PTF) and direct measurement with a double ring infiltrometer. Among the 12 MpL, we found the highest SOC content in slopes with mixed tree vegetation and Phaeozem soils. However, SOC retention decreased by 40%–50% due to sealing surfaces. For infiltration measures, despite the diversity of soils and vegetation, direct measurements values are highly homogeneous, while values calculated using PTFs better reflect the morphopedological landscape heterogeneity. In all the MpLs, the hydraulic conductivity was higher than the maximum rainfall intensity report, indicating that the soils in Chapultepec Park, despite the differences in soils and intensity of use, provide the ecosystem service of infiltration. These results would allow the establishment of a baseline for monitoring these services and provide information to decision makers and urban planners seeking to reduce the construction of gray infrastructure that seals soils and reduces their capacity to provide these ecosystem services.

Comparing Alternative Non-Selective Herbicides in Oregon and New Mexico

Abstract Municipalities are considering alternatives to traditional herbicides for suppressing weeds and vegetation in areas frequented by the public. Two field experiments were conducted to test the efficacy of alternative non-selective herbicides: one in Corvallis, Oregon, on a mixed lawn of perennial ryegrass, annual bluegrass, and broadleaf weeds, and another experiment in Las Cruces, New Mexico, on a predominantly bermudagrass lawn with broadleaf weeds. The experimental objective was to quantify and compare the effects of repeated applications of ten non-selective herbicides to terminate a lawn with mixed vegetation. Applications were made every two weeks for four applications starting on 15 April 2022 in Corvallis and 26 May 2022 in Las Cruces. Data collected included the percent green cover over time calculated using an area under the percent green cover progress curve (AUPGCPC), the percent green cover at the conclusion of the experiment, and the change in monocot and dicot density over the course of the experiment. All treatments resulted in a lower AUPGCPC compared to water only except for mint oil + sodium lauryl sulfate + potassium sorbate. The only treatments with an average percent green cover less than 50% was a combination of ammoniated soap of fatty acids + maleic hydrazide (47% green cover) in Corvallis and pelargonic acid (38%) in Las Cruces, suggesting that more applications would be needed to terminate the lawn under similar circumstances. At the conclusion of the experiment, the water only plots averaged 90% and 93% green cover in Corvallis and Las Cruces, respectively. The change of monocot and dicot densities over the course of the experiment indicated that some of the products tested may be more sensitive to dicots, or in some cases monocots, suggesting a potential for future selective herbicide research in certain locations and climates.

Olive Growing Farming System and Damage by Cicadas

Although cicadas have traditionally been considered pests of little or no importance, in recent decades, an increase in damages is being recorded in olive groves of southern Spain. New agricultural practices that affect soil management are behind it. During 2024, intensive sampling has been carried out in an organic grove with herbaceous cover (VC2), and in a second one with mixed vegetation cover (VC1, in which the crushed remains of the annual pruning are added). In both ecological groves, inventories of the vegetation have been carried out, as well as intensive sampling in the olive canopy, with the densities of oviposition injuries being recorded and compared with respect to conventional management (CONV). The objectives of this study are to compare the three managements based on the density of oviposition injuries, to determine the priority areas for cicadas’ oviposition within the trees; and to develop a sampling method to assess damage over large areas. The results show significant increases in the density of injuries in organic groves, with maximum values recorded in the olive grove with mixed cover. Oviposition injuries show an altitudinal gradient distribution, with maximum values in the lower zone of the trees. The factors involved are discussed.

The Combined Effect of Taproot and Fibrous Roots of Herbaceous Plants and Shrubs on the Distribution of Soil Water-Stable Aggregates

Soil aggregation, an important indicator of soil restoration in degraded ecosystems, is a fundamental unit of soil structure. However, research on the influence of grass–shrub composites on the distribution of &gt;0.25 mm soil water-stable aggregates (macroaggregates) is scarce. Therefore, this study focuses on the hill and gully region of the Loess Plateau, where vegetation has been well restored since the return of farmland to forests and grasslands. The study investigated the root and macroaggregate distribution characteristics and interrelationships of three widely distributed mixed vegetation types of Caragana korshinskii and Agropyron cristatum (C-AC), C. korshinskii and Bothriochloa ischaemum (C-BI), and C. korshinskii and Artemisia gmelinii (C-AG) in this area. The results indicate that soil macroaggregates decrease with increasing depth. Due to the spatial differences in the distribution of shrub root, the content of macroaggregates at 50 cm from the shrub base was higher than that at the shrub base, with an increase of 25.98%–34.27% in different vegetation associations. In this study, the root length density and root diameter better reflected the influence of roots on the distribution of macroaggregates, and the product of the two had a good power function relationship with the content of macroaggregates (R2 ≥ 0.82, p &lt; 0.01). Grey correlation analysis showed that the influence of root length density on the distribution of large aggregates was greater than that of root diameter. The content of macroaggregates in the vegetation association of taproot herbaceous plants and shrubs was higher than that of fibrous root herbaceous plants. The average soil macroaggregate content in the C-AG was 15.79%–248.6% higher than that in the C-BI and C-AC. In this study, the spatial distribution differences in root caused by shrub growth were the main reason for the spatial heterogeneity of soil macroaggregate content distribution. The improvement ability of soil macroaggregates was higher in the combination of taproot herbaceous plants and shrubs than in the combination of fibrous root herbaceous plants and shrubs. The results of this study can, to some extent, reveal the influence and mechanisms of plant roots on soil aggregates in grass–shrub vegetation association.

Non-typhoidal Salmonella among slaughterhouse workers and in the pork value chain in selected districts of Uganda.

Non-typhoidal Salmonella (NTS) is a major cause of gastroenteritis worldwide, often associated with meat consumption and meat processing. Research on NTS infection and circulating serovars in meat value chains in Uganda is limited. We aimed to establish NTS prevalence, antimicrobial resistance, and risk factors among slaughterhouse workers, and to identify potentially zoonotic serovars in the pork value chain. We conducted a nationwide cross-sectional survey, collecting 364 stool samples from livestock slaughterhouse workers and 1,535 samples from the pork value chain: mesenteric lymph nodes, fecal samples, swabs of carcass splitting floor, cleaning water, meat handlers hand swabs, carcass swabs, raw pork, cooked pork, and mixed raw vegetables. Samples were cultured for isolation of NTS, and subsequently serotyped according to White-Kauffmann-Le Minor scheme. Antimicrobial resistance profiles were determined using tube microdilution and Sensititre® EUVSEC3® plates. Semi- structured questionnaires with 35 questions were used to collect data on demographics, work related risk factors and activities outside the slaughterhouse. Overall NTS prevalence was 19.2% (365/1899). Proportions at slaughter were; 46.7% in floor swabs, 30.5% in carcass swabs, 20.5% in pig faeces,19.2% in mesenteric lymph nodes,18.4% in hand swabs, 9.5% in water and 5.2% in slaughterhouse workers. At retail, proportions were 33.8% in pork chopping surface, 33.1% in raw pork, 18.9% in hand swabs, 4.0% in cooked pork and 0.7% in vegetables. Sixty-one serovars were identified, with significant overlap between humans and the pork value chain. Overall, zoonotic S. Zanzibar, monophasic serovars of S. subspecies salamae (II) and subspecies enterica (I), S. Typhimurium and S. Newport, were the most prevalent. S. Typhimurium was predominant in humans and exhibited multi-drug resistance. NTS infection was significantly associated with eating, drinking, or smoking while working (OR = 1.95, 95% CI: 0.67-2.90%, p = 0.004). The detected NTS serovars in slaughterhouse workers could be a potential indicator of circulating serovars in the general population. The persistent presence of NTS along the pork value chain highlights occurrence of cross-contamination and the potential for transmission to consumers and slaughterhouse workers. This emphasizes the need to reduce Salmonella prevalence on pig farms and improve hygiene and pork handling practices at slaughter and retail points.

An analysis of the relationship between domestic trade costs and the dietary quality of Chinese residents

Abstract Domestic trade flow in China is an indispensable factor affecting food availability to the public. The aim of this study is to focus on the cost of domestic trade within China and the dietary health of Chinese residents. Based on the China-regional input-output tables and the CHNS micro-database, we calculated China’s domestic trade costs and Healthy Eating Index (HEI) of Chinese urban and rural residents. We find that domestic trade costs are negatively correlated with residents’ whole grain and mixed beans, vegetables, fruits, beef, mutton, poultry, and aquatic products consumption, having a significant negative influence on residents’ dietary quality score. Domestic trade costs can influence residents’ food consumption structure by affecting income and traditional market scores. Domestic trade costs have a greater negative influence on the dietary quality of rural residents, low-income residents, and elderly residents. The results suggest that reducing domestic trade costs increased residents’ food consumption and improved their dietary quality. Increasing the people’s income and stimulating traditional markets can alleviate the decline in dietary quality of the population caused by an increase in domestic trade costs.

Effect of different cooking oils and methods on physicochemical, nutritional, and microbial safety for mixed vegetables focusing on Bangladesh

SummaryCooking is an essential aspect of everyday life. Cooking oils and methods exert enormous effects on the nutritional, physicochemical, microbial qualities, and bioactive compounds of vegetables. Most of them are either directly or indirectly related to human health. Hence, the present investigation was undertaken to find out the effect of two cooking methods (traditional and steam cooking) and four selected culinary oils (soybean oil, mustard oil, extra virgin olive oil, and extra virgin coconut oil) on the cooked vegetables. The results indicated that steam‐cooked mixed vegetables retained more nutrients than traditional ones. The traditional cooking method of preparing mixed vegetables with soybean oil revealed higher amounts of crude fat, 26.90 ± 0.10%, whereas steam cooking and traditionally cooked vegetables without oils showed lower amounts of crude fat, 1.21 ± 0.04%, and 1.94 ± 0.04%, respectively. The highest crude fibre from 5.68 ± 0.20 to 6.48 ± 0.02% was recorded by the steam‐cooked vegetables in comparison with traditionally prepared mixed vegetables. Traditionally cooked vegetables with mustard oil showed a higher crude protein (13.30 ± 0.10%). The mixed vegetables that were steam‐cooked using extra virgin olive oil revealed a decreased percent of carbohydrates, 49.42 ± 0.03%. Most of the essential minerals especially for the human body like Ca, Mg, Fe, Cu, and Zn were found notable in both traditional and steam‐cooking processes using extra virgin olive oil, and mustard oil. The leading bioactive compound ß‐carotene 67.04 ± 0.04 mg/100 g was noted by the steam‐cooked vegetables with mustard oil. The highest anthocyanin 32.69 ± 0.02 mg/100 g and ascorbic acid 42.31 ± 0.01 mg/100 g were recorded in the steam‐cooked vegetables without culinary oils. Steam‐cooking with extra virgin coconut and olive oil resulted in high total carotenoid and phenolic content (31.60 ± 0.05 and 3.11 ± 0.04 mg/100 g, respectively). However, the findings suggest that culinary oils used in the present study retained more essential minerals and bioactive compounds than soybean oil. Only sufficient amount of edible oil may be used for vegetables cooking and proper functioning of fat‐soluble vitamins.

Quantifying heterogeneity of hominin environments in and out of Africa using herbivore dental traits

Our own species, Homo sapiens, has been able to invade near-all global ecosystems through a unique form of ecological plasticity. To understand how Homo sapiens have been able to disperse to such a wide range of environments, we need to understand the origins of the characteristic which enabled this, plasticity. Growing evidence indicates that Homo species were already able to occupy a diverse set of environments in the Early Pleistocene, suggesting that the origins of human ecological plasticity have deeper roots than previously anticipated. We analysed the distribution of two dental traits, mean ordinated hypsodonty of large herbivores and proboscidean mesowear, across the mammalian communities at Early Pleistocene hominin sites, to infer the vegetation and climate contexts of these locations. The global distribution of community-level dental traits suggests that, while open grassy vegetation made up a large proportion of the sites, mixed and wooded vegetation was also represented. From our analysis we conclude that Early Pleistocene Homo species were able to exploit habitats with different vegetation types and occupied a range of different environments. In addition to this we found that the distribution of dental traits of mammalian communities in the Eurasian sample was notably different from that of the African sample, suggesting that Homo's dispersal into Eurasia resulted in a niche expansion. Together these findings suggest that Homo in the Early Pleistocene was ecologically plastic and occupied a wide environmental niche space.

Investigating Methane, Carbon Dioxide, Ammonia, and Hydrogen Sulphide Content in Agricultural Waste during Biogas Production

The agricultural industry produces a substantial quantity of organic waste, and finding a suitable method for disposing of this highly biodegradable solid waste is a difficult task. The utilisation of anaerobic digestion for agricultural waste is a viable technological solution for both renewable energy production (biogas) and waste treatment. The primary objective of the study was to assess the composition of biogas, namely the percentages of methane, carbon dioxide, ammonia, and hydrogen sulphide. Additionally, the study aimed to quantify the amount of biogas produced and determine the methane yield (measured in NmL/g VS) from different agricultural substrates. The biochemical methane potential (BMP) measurements were conducted in triplicate using the BPC Instruments AMPTS II instrument. The substrates utilised in the investigation were chosen based on their accessibility. The substrates used in this study comprise cattle manure, chicken manure, pig manure, tomato plants, tomatoes, cabbage, mixed fruits, mixed vegetables, dog food, and a co-digestion of mixed vegetables, fruits, and dog food (MVMFDF). Prior to the cleaning process, the makeup of the biogas was assessed using the BIOGAS 5000, a Geotech Analyser. The AMPTS II flow cell automatically monitored and recorded the volume of bio-methane produced after the cleaning stage. The data were examined using the Minitab-17 software. The co-digestion of mixed vegetables, mixed fruits, and dog food (MVMFDF) resulted in the highest methane level of 77.4%, followed by mixed fruits at 76.6%, pig manure at 72.57%, and mixed vegetables at 70.1%. The chicken manure exhibited the greatest levels of ammonia (98.0 ppm) and hydrogen sulphide (589 ppm). Chicken manure had the highest hydrogen sulphide level, followed by pig manure (540 ppm), tomato plants (485 ppm), mixed fruits (250 ppm), and MVMFDF (208 ppm). Ultimately, the makeup of biogas is greatly affected by the unique qualities of each substrate. Substrates containing elevated quantities of hydrogen sulphide, such as chicken manure, require the process of biogas scrubbing. This is because they contain substantial amounts of ammonia and hydrogen sulphide, which can cause corrosion to the equipment in biogas plants. This emphasises the crucial need to meticulously choose substrates, with a specific focus on their organic composition and their capacity to generate elevated methane levels while minimising contaminants. Substrates with a high organic content, such as agricultural waste, are optimal for maximising the production of methane. Furthermore, the implementation of biogas scrubbing procedures is essential for efficiently decreasing carbon dioxide and hydrogen sulphide levels in biogas. By considering and tackling these problems, the effectiveness of biogas generation can be enhanced and its ecological consequences alleviated. This strategy facilitates the advancement of biogas as a sustainable energy source, hence contributing to the attainment of sustainable development goals (SDGs).

Prevalence and characterization of foodborne pathogens isolated from fresh-cut fruits and vegetables in Beijing, China

Pre-cut fresh fruits and vegetables are highly appealing to consumers for their convenience, however, as they are highly susceptible to microbial contamination in processing, the potential risks of foodborne illnesses to public health are not negligible. This study aimed to assess the prevalence, antibiotic susceptibility and molecular characteristics of major foodborne pathogens (Listeria monocytogenes, Escherichia coli, Staphylococcus aureus and Salmonella) isolated from fresh-cut fruits and vegetables in Beijing, China. 86 stains were isolated from 326 samples, with S. aureus being the highest prevalence (15.38 %), followed by E. coli (9.23 %) and L. monocytogenes (1.85 %), while no Salmonella was detected. The prevalence by type of food indicated that fruit trays and mixed vegetables were more susceptible to contamination by pathogens. 98 % of S. aureus were resistant to at least of one antibiotic, and showed a high resistance rate to benzylpenicillin (90 %) and oxacillin (48 %). Among 25 E. coli isolates, 57.67 % of which exhibited multi-drug resistance, with common resist to trimethoprim/sulfamethoxazole (66.67 %) and ampicillin (63.33 %). A total of 9 sequence types (STs) and 8 spa types were identified in 35 S. aureus isolates, with ST398-t34 being the predominant type (42.86 %). Additionally, analysis of 25 E. coli isolates demonstrated significant heterogeneity, characterized by 22 serotypes and 18 STs. Genomic analysis revealed that 5 and 44 distinct antibiotic resistance genes (ARGs) in S. aureus and E. coli, respectively. Seven quinolone resistance-determining regions (QRDRs) mutations were identified in E. coli isolates, of which GyrA (S83L) was the most frequently detected. All the S. aureus and E. coli isolates harbored virulence genes. ARGs in S. aureus and E. coli showed a significant positive correlation with plasmids. Furthermore, one L. monocytogenes isolate, which was ST101 and serogroupIIc from watermelon sample, harbored virulence genes (inlA and inlB) and LIPI-1 pathogenic islands (prfA, plcA, hly and actA), which posed potential risks for consumer's health. This study focused on the potential microbial risk of fresh-cut fruits and vegetables associated with foodborne diseases, improving the scientific understanding towards risk assessment related to ready-to-eat foods.

Variation in Soil CO2 Fluxes across Land Cover Mosaic in Typical Tundra of the Taimyr Peninsula, Siberia

Increased warming in the Arctic is of great concern. This is particularly due to permafrost degradation, which is expected to accelerate microbial breakdown of soil organic carbon, with its further release into the atmosphere as carbon dioxide (CO2). The fine-scale variability of CO2 fluxes across highly mosaic Arctic tundra landscapes can provide us with insights into the diverse responses of individual plant communities to environmental change. In the paper, we contribute to filling existing gaps by investigating the variability of CO2 flux rates within different landscape units for dominant vegetation communities and plant species across typical tundra of the southern part of the Taimyr Peninsula, Siberia. In general, the variability of soil CO2 flux illustrates a four-fold increase from non-vascular vegetation, mainly lichens and mosses (1.05 ± 0.36 µmol m−2 s−1), towards vascular plants (3.59 ± 0.51 µmol m−2 s−1). Barren ground (“frost boils”) shows the lowest value of 0.79 ± 0.21 µmol m−2 s−1, while considering the Arctic “browning” phenomenon, a further substantial increase of CO2 flux can be expected with shrub expansion. Given the high correlation with top soil temperature, well-drained and relatively dry habitats such as barren ground and non-vascular vegetation are expected to be the most sensitive to the observed and projected temperature growth in the Arctic. For mixed vegetation and vascular species that favor wetter conditions, soil moisture appears to play a greater role. Based on the modeled seasonal pattern of soil CO2 flux and precipitation records, and applying the rainfall simulations in situ we outlined the role of precipitation across enhanced CO2 emissions (i.e., the “Birch” effect). We found that a pulse-like growth of soil CO2 fluxes, observed within the first few minutes after rainfall on vegetated plots, reaches 0.99 ± 0.48 µmol m−2 s−1 per each 1 mm of precipitation, while barren ground shows 55–70% inhibition of CO2 emission during the first several hours. An average additive effect of precipitation on soil CO2 flux may achieve 7–12% over the entire growing season, while the projected increased precipitation regime in the Arctic may strengthen the total CO2 release from the soil surface to the atmosphere during the growing season.

Dispersal‐related plant traits are associated with range size in the Atlantic Forest

AbstractAimThe efficiency of animal‐mediated seed dispersal is threatened by the decline of animal populations, especially in tropical forests. We hypothesise that large‐seeded plants with animal‐mediated dispersal tend to have limited geographic ranges and face an increased risk of extinction due to the potential decline in seed dispersal by large‐bodied fruit‐eating and seed‐dispersing animals (frugivores).LocationAtlantic Forest, Brazil, South America.TaxonAngiosperms.MethodsFirst, we collected dispersal‐related traits (dispersal syndrome, fruit size, and seed size), growth form (tree, climber, and other) and preferred vegetation type (open and closed) data for 1052 Atlantic Forest plant species. Next, we integrated these with occurrence records, extinction risk assessments, and phylogenetic trees. Finally, we performed phylogenetic generalised least squares regressions to test the direct and interactive effects of dispersal‐related traits and vegetation type on geographical range size.ResultsLarge‐seeded species had smaller range sizes than small‐seeded species, but only for species with animal‐mediated dispersal, not for those dispersed by abiotic mechanisms. However, plants with abiotic dispersal had overall smaller range sizes than plants with animal‐mediated dispersal. Furthermore, we found that species restricted to forests had smaller ranges than those occurring in open or mixed vegetation. Finally, at least 29% of the Atlantic Forest flora is threatened by extinction, but this was not related to plant dispersal syndromes.Main ConclusionsLarge‐seeded plants with animal‐mediated dispersal may be suffering from dispersal limitation, potentially due to past and ongoing defaunation of large‐bodied frugivores, leading to small range sizes. Other factors, such as deforestation and fragmentation, will probably modulate the effects of dispersal on range size, and ultimately extinction. Our study sheds light on the relationship between plant traits, mutualistic interactions, and distribution that are key to the functioning of tropical forests.

Using a Public Preference Questionnaire and Eye Movement Heat Maps to Identify the Visual Quality of Rural Landscapes in Southwestern Guizhou, China

Rural landscapes serve as important platforms to determine the landscape characteristics (LCs) of rural areas, demonstrating the landscape characteristics specific to certain regions to the public. However, the development trend of urban and rural areas is continuous and impacts the characteristics of rural landscapes, which directly affects the public’s visual experience and landscape perception. In order to improve the characteristics of rural landscapes, this study evaluates and analyzes their visual quality based on public preferences and eye movement heat maps. The results show that most subjects have a high preference for horizontal, open-view rural landscapes with fields and landform features as the dominant landscape elements. This study also found that the combination of strip-like or planar settlement buildings with regional characteristics and landform features has an active impact on the visual quality of rural landscapes. These results show that rural landscapes characterized by scattered settlement buildings without significant regional characteristics, horizontally curved roads, bridges, and other human-made landscape elements, and mixed and disorderly vegetation have low landscape preference, which degrades their visual quality. These research results provide crucial suggestions for landscape managers to protect and renew rural landscape features.

A New Attempt to Estimate Underground Soil Leakage through High-Density, Fixed-Point Monitoring in a Typical Karst Rocky Desertification Region

Understanding soil loss pathways in karst regions is crucial for erosion control. Combining high-density measurements of grid points with runoff plot monitoring, we attempt to use a new indirect method to study the characteristics of soil loss in karst rocky desertification areas of Salaxi Town, Guizhou province. One cycle year monitoring data of 12640 grid points were applied in the soil loss analysis. This study identifies underground leakage as the primary pathway of soil loss, with an mean soil leakage of 21.51 kg in potential areas, accounting for 83.12%, and an average leakage of 22.69 kg in in mild karst rocky desertification areas accounting for 81.48%. Mixed vegetation types (forest, shrub, and grass) were better at preventing surface soil loss but increased underground leakage compared to single vegetation types. The rainy season significantly influences soil erosion, accounting for 67.88% of total loss, with slight variations among different karst rocky desertification grades and vegetation types. Mean underground leakage rates during the rainy and dry seasons are 63.34% and 36.66%, respectively. Although this method still has certain limitations, it plays a positive role in revealing the mechanism of soil erosion processes in karst regions.

Effects of spatial variability in vegetation phenology, climate, landcover, biodiversity, topography, and soil property on soil respiration across a coastal ecosystem

Coastal terrestrial-aquatic interfaces (TAIs) are crucial contributors to global biogeochemical cycles and carbon exchange. The soil carbon dioxide (CO2) efflux in these transition zones is however poorly understood due to the high spatiotemporal dynamics of TAIs, as various sub-ecosystems in this region are compressed and expanded by complex influences of tides, changes in river levels, climate, and land use. We focus on the Chesapeake Bay region to (i) investigate the spatial heterogeneity of the coastal ecosystem and identify spatial zones with similar environmental characteristics based on the spatial data layers, including vegetation phenology, climate, landcover, diversity, topography, soil property, and relative tidal elevation; (ii) understand the primary driving factors affecting soil respiration within sub-ecosystems of the coastal ecosystem. Specifically, we employed hierarchical clustering analysis to identify spatial regions with distinct environmental characteristics, followed by the determination of main driving factors using Random Forest regression and SHapley Additive exPlanations. Maximum and minimum temperature are the main drivers common to all sub-ecosystems, while each region also has additional unique major drivers that differentiate them from one another. Precipitation exerts an influence on vegetated lands, while soil pH value holds importance specifically in forested lands. In croplands characterized by high clay content and low sand content, the significant role is attributed to bulk density. Wetlands demonstrate the importance of both elevation and sand content, with clay content being more relevant in non-inundated wetlands than in inundated wetlands. The topographic wetness index significantly contributes to the mixed vegetation areas, including shrub, grass, pasture, and forest. Additionally, our research reveals that dense vegetation land covers and urban/developed areas exhibit distinct soil property drivers. Overall, our research demonstrates an efficient method of employing various open-source remote sensing and GIS datasets to comprehend the spatial variability and soil respiration mechanisms in coastal TAI. There is no one-size-fits-all approach to modeling carbon fluxes released by soil respiration in coastal TAIs, and our study highlights the importance of further research and monitoring practices to improve our understanding of carbon dynamics and promote the sustainable management of coastal TAIs.

Topography influences diurnal and seasonal microclimate fluctuations in hilly terrain environments of coastal California.

Understanding the topographic basis for microclimatic variation remains fundamental to predicting the site level effects of warming air temperatures. Quantifying diurnal fluctuation and seasonal extremes in relation to topography offers insight into the potential relationship between site level conditions and changes in regional climate. The present study investigated an annual understory temperature regime for 50 sites distributed across a topographically diverse area (>12 km2) comprised of mixed evergreen-deciduous woodland vegetation typical of California coastal ranges. We investigated the effect of topography and tree cover on site-to-site variation in near-surface temperatures using a combination of multiple linear regression and multivariate techniques. Sites in topographically depressed areas (e.g., valley bottoms) exhibited larger seasonal and diurnal variation. Elevation (at 10 m resolution) was found to be the primary driver of daily and seasonal variations, in addition to hillslope position, canopy cover and northness. The elevation effect on seasonal mean temperatures was inverted, reflecting large-scale cold-air pooling in the study region, with elevated minimum and mean temperature at higher elevations. Additionally, several of our sites showed considerable buffering (dampened diurnal and seasonal temperature fluctuations) compared to average regional conditions measured at an on-site weather station. Results from this study help inform efforts to extrapolate temperature records across large landscapes and have the potential to improve our ecological understanding of fine-scale seasonal climate variation in coastal range environments.

Use of different dry materials to control the moisture in a black soldier fly (Hermetia illucens) rearing substrate.

Controlling the substrate moisture is a significant challenge in black soldier fly (BSF) farming. Many substrates have a high moisture content, which results in a low BSF biomass and a high mortality. One potential solution involves incorporating dry substrates into the food mix to mitigate the excessive moisture. However, little information about the types and quantities of dry substrates is available. Six different dry materials-rice husk (RH), rice bran (RB), rice husk ash (RHA), coconut coir dust (CC), rubberwood sawdust (RSD), and spent coffee grounds (SCGs)-were evaluated by combining with pure minced mixed vegetables in varying proportions (0%, 5%, 10%, 15%, 25%, and 50% by weight). This study encompassed both small-scale and medium-scale experiments to comprehensively assess the effects of the addition of each of these different dry substrates and their quantities on aspects of the development of BSF, such as BSF biomass, larval duration, mortality rates, adult sex ratio, and the moisture removal efficiency of each substrate mixture. Each dry substrate had specific properties. Although RB emerged as a favorable dry substrate owing to its nutritional content and substantial water-holding capacity, excessive use of RB (>15% by weight) resulted in elevated temperatures and subsequent desiccation of the substrate, potentially leading to larval mortality. In contrast, RH demonstrated the ability to support improved larval duration and growth, permitting its utilization in higher proportions (up to 50%). On the other hand, CC, RHA, and SCG are better suited for inclusion in BSF larval substrates in smaller quantities. Some dry substrates require a pretreatment process to eliminate toxic substances prior to their incorporation into substrate mixtures, such as CC and SCG. A potential alternative solution involves employing a combination of various dry substrates. This approach aims to enhance the substrate moisture control and subsequently improve the BSF rearing performance.