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The presence of exotic species of plants in a region is associated with anthropogenic activities due to their economic and commercial benefits. When these exotic species hinder the development of native species, they are considered invasive. In Brazil, two species stand out: Pinus spp. and Eucalyptus spp. Their presence within ecosystems may result in environmental imbalances caused by allelopathy. The allelochemicals released by these invasive species can enter the environment through rainfall, decomposition of plant material, root exudation, and volatilization. The high solubility of phenolic compounds produced by these plants allows them to reach water bodies and potentially affect aquatic organisms. In light of this, a toxicological evaluation was conducted by exposing Daphnia magna, Aliivibrio fischeri, Landoltia punctata, and Lactuca sativa seeds to soil elutriates from areas with exotic and native vegetation. The samples were collected in close proximity, with the primary difference being the type of vegetation cover. Upon characterization, the soil covered by native species was found to contain higher levels of organic matter and moisture, whereas the soil with exotic species appeared drier. Overall, the toxicological evaluation revealed that elutriates from native vegetation induced greater toxic effects on the aquatic organisms D. magna and A. fischeri. Conversely, elutriates from exotic vegetation showed lower concentrations of total phenolic compounds but still exhibited toxic effects on the development of L. sativa seeds and caused notable structural damage to the aquatic macrophyte L. punctata.. This study highlights the importance of investigating reforested areas dominated by exotic species to better understand the potential environmental impacts caused by invasive plants.

期刊论文 2025-09-01 DOI: 10.1016/j.actao.2025.104085 ISSN: 1146-609X

Context Invasive plants are one of the most significant threats to woodlands globally. Methods of invasive plant control include manual removal and herbicide application. While the impacts of control methods on invasive and off-target native plant species are often explored, the impacts on below-ground organisms, such as fungi, are less well understood.Aims We conducted a glasshouse trial to investigate the responses of soil fungal communities to herbicides and manual removal that are used to control common invasive plant species in Banksia woodland in south-western Australia.Methods Broad spectrum (glyphosate and pelargonic acid) and grass-specific (fluazifop-p-butyl) herbicides were separately applied to pots containing either Ehrharta calycina, a key invasive grass species or Eucalyptus todtiana, a native woodland tree at the recommended woodland rate. After six weeks, samples of treated soils were subjected to high throughput sequencing to determine fungal community diversity, richness, relative abundance, composition and putative ecosystem function.Key results Pelargonic acid induced the widest range of changes including decreased fungal richness and Shannon diversity but all herbicides affected community composition. Within functional groups, fluazifop-p-butyl led to a significant decrease of symbiotrophs in the mycorrhizal species.Conclusions We show that invasive species management, in the manner applied, can lead to immediate changes in fungal community composition.Implications Observed patterns require further exploration, particularly repeat testing under different environmental conditions, to better determine the impact and mode of action of herbicides on below-ground organisms. The functional changes in the soil fungal community could further disturb the soil fungal community and complicate subsequent management considerations.

期刊论文 2025-01-01 DOI: 10.1071/BT24083 ISSN: 0067-1924

BACKGROUNDA major impact of invasive Myocastor coypus in their introduction range is the collapse of riverbanks and nearby infrastructure, such as railway lines, due to the species' burrowing activities. Because widespread implementation of preventive measures along watercourses is unfeasible, identifying susceptible areas is key to guide targeted management actions. This study used species-habitat models to: (i) identify local environmental features of the railway line/watercourse intersections (RLWIs) that make them particularly susceptible to coypu damage, and (ii) predict species occurrence probability over a wide lowland-hilly area of northern Italy (Lombardy) to identify priority areas for monitoring. RESULTSLocal-scale models identified that the RLWIs most susceptible to burrowing were those surrounded by arable land with interspersed hedgerows locally characterized by high herbaceous vegetation and clay soil. In urbanized areas and areas of intensive agriculture, coypu dens were generally located significantly closer to the railway, increasing the risk of collapse. A landscape-scale species distribution model showed that lowland areas along major rivers and lake shores, and also agricultural areas with a dense minor hydrographic network, particularly in the southeast of the study area, are more likely to be occupied by coypu. CONCLUSIONLocal-scale models showed that specific environmental characteristics increase the risk of burrowing near RLWIs. The landscape-scale model allowed us to predict which areas require thorough monitoring of RLWIs to search for such local characteristics to implement preventive management measures. The proposed model-based framework can be applied to any geographical context to predict and prevent coypu damage. (c) 2024 Society of Chemical Industry.

期刊论文 2024-11-01 DOI: 10.1002/ps.8128 ISSN: 1526-498X

Ecological zonation in coastal forests is driven by sea level rise and storm-surge events. Mature trees that can survive moderately saline conditions show signs of stress when soil salinity increases above its tolerance levels. As leaf burn, foliar damage, and defoliation reduce tree canopy cover, light gaps form within the crown. At the forest-marsh edge, canopy cover loss is most severe; trunks of dead trees without canopies form ghost forests. Canopy thinning and light from the edge alter conditions for understory vegetation, promoting the growth of shrubs and facilitating establishment and spread of invasive species that were previously limited by light competition. In this research, we present an analysis of illuminance and temperature in a coastal forest transitioning to a salt marsh. Light sensors above the ground surface were used to measure light attenuation of trees and understory vegetation and to observe the effect of reduced canopies at the forest-marsh edge. Farther from the marsh, where salinity is lower and trees are healthy, dense canopies attenuate light. We estimate that during the growing season, tree canopies intercept 50% of illuminance on average. Closer to the marsh, canopy thinning, and tree death allow greater light penetration from above, as well as from the adjacent marsh. These illuminance values are further increased by light penetration from the forest-marsh edge (edge effect). Here, higher illuminance may permit Phragmites australis expansion. At intermediate locations, trees intercept between 32% and 49% of light and the understory shrub Morella cerifera intercepts a further 45% of penetrating light based on comparisons of illuminance above and below shrub canopies. Light penetration from the edge can also be felt. The presence of M. cerifera reduces the air temperature close to the soil surface, creating a cooler summer microclimate. The tree health state is reflected in the canopy size. The canopy patterns and the edge effect are responsible for light availability distribution along forest-marsh gradients, consequently affecting the understory vegetation biomass. We conclude that during forest retreat driven by sea level rise, tree dieback increases light availability favoring the temporary encroachment of Ph. australis and M. cerifera in the understory.

期刊论文 2024-10-01 DOI: 10.1002/ecs2.70021 ISSN: 2150-8925

Nowadays, in addition to the destruction and fragmentation of the world's habitats, invasive species, and damage caused by them, are one of the most important factors in the destruction of ecosystems. The raccoon (Procyon lotor) is a medium-sized mammal that is placed in mid-levels of the food web and can affect a wide range of species. Considering the damage done to local ecosystems by this invasive species, habitat assessment and determining the factors affecting its habitat suitability would be a key step in managing this species. In this study, using the MaxEnt model and examining 12 environmental parameters (elevation, slope, aspect, geological units, soil type, vegetation, land use, distance to villages, distance to main roads, distance to waterways, average temperature, and rainfall) in the west of Guilan Province, habitat suitability of this alien species was determined, and the most important factors affecting this suitability were investigated. Results showed that the validity value of the model (AUC) was estimated to be 0.852 and parameters such as distance to village (34.5%), elevation (24.2%), and land use (15.9%) are among the most important and effective factors. Also, the results showed that 0.60% of the study area has high suitability, 6.14% moderate, 24.87% low, and 68.36% unsuitable areas for raccoons. The overall result shows that despite the lack of vast favorable areas for this invasive species, an increase in the number and expansion of this species is very likely because of its omnivorous diet, high adaptability to different environments and conditions, as well as extensive niche. All of these factors cause raccoons to spread further in the region and consequently increase the risks and damages to the native ecosystem.

期刊论文 2024-08-01 DOI: 10.1002/ece3.70090 ISSN: 2045-7758

Tea gardens are established on acidic soils (pH < 5.5) and undergo extensive fertilization to maximize yield, which inadvertently promotes the proliferation of various weed species. Commelina communis and Tradescantia fluminensis (Commelinaceae) are major threats to tea plantations causing the highest destruction compared to other weed species. This study investigated the mechanisms behind the tolerance exhibited toward elevated aluminum (Al) concentrations in acidic soils and its contribution to these species' invasive behavior and herbicide resistance. Both species displayed only a 17-22% reduction in biomass under 400 M Al, and the Al accumulation remained low, ranging between 100 and 200 mu g g(-1) DW. Interestingly, C. communis responded to low to moderate Al levels (50-150 mu M Al3+) with growth stimulation. Antioxidant enzyme activity and flavonoid and anthocyanin leaf concentrations increased with Al treatment concentrations. Surprisingly, exposure of plants to Al, particularly at the 50 mu M threshold, resulted in a significant reduction in leaf damage inflicted by a spectrum of herbicides (paraquat, glyphosate, clethodim, and 2,4-D), with the effect more pronounced in C. communis. Our results demonstrate that enhancement of antioxidant enzymes and accumulation of detoxifying metabolites, coupled with the accumulation of pivotal intermediates of metabolic pathways under Al treatment collectively contribute to enhanced resistance against an array of herbicides. These findings provide insights into the invasive propensity of C. communis and T. fluminensis, particularly in acidic soil conditions prevalent in tea gardens.

期刊论文 2024-07-01 DOI: 10.1007/s10530-024-03318-1 ISSN: 1387-3547

Organic matter is sometimes added to soil in wetland mitigation projects, putatively to improve restoration outcomes. At a freshwater mitigation wetland, built in a former agricultural field to compensate for development-related wetland losses elsewhere, we conducted a manipulative field experiment using organic matter amendments to identify the effects different types and loading rates had on the development of soil (organic matter, bulk density, and hydric soil indicators), vegetation (root and shoot biomass, floristic quality), and methane (CH4) emissions. The amendments included cow manure, composted wood chips, and hay at various loading rates, and municipal wastewater Class A biosolids. We found that there were trade-offs in desired restoration outcomes. Experimental loading rates of hay (226 m3 ha-1) and manure (339 and 678 m3 ha-1) produced more CH4 (78-92 g m-2 year-1) than unamended plots (28 g m-2 year-1). These same amendments had little effect on hydric soil indicators (e.g., redox potential and reduced iron). Manure almost doubled vegetation biomass (937 g m-2 versus 534 g m-2) compared to the unamended control, largely due to the growth of Typha sp. (cattail), an undesired plant at this site that resulted in lower floristic quality. Compared to unamended soils, only wood chips appeared to increase soil organic matter after one growing season. All amendments tended to reduce soil bulk density and penetration resistance, but these were not correlated with root growth. Unexpectedly, hydrology varied considerably due to patchy soil characteristics, despite little variation in elevation - this strongly influenced on our results. We qualitatively observed that constantly inundated plots had lower CH4 emissions than areas with wet-dry cycles and that cattail proliferated mostly in wetter areas. Contrary to the prescription of organic matter amendments as a method for accelerating soil and vegetation development in wetland restoration projects, our findings demonstrate that amendments may not be necessary to support vegetation and hydric soil development and might unnecessarily exacerbate atmospheric warming and contribute to invasive species spread.

期刊论文 2024-04-01 DOI: 10.1007/s11273-023-09967-8 ISSN: 0923-4861

Wetland area and condition are declining globally despite their importance to climate change mitigation and biodiversity. Introduced ungulate species are contributing to the global decline. Their impacts on wetlands are widespread and varied, however poorly understood. We summarise global impacts of introduced unmanaged and domesticated ungulates on wetlands highlighting potential outcomes of their removal. We place an emphasis on Australia due to the disproportionate impacts of ungulates on wetlands and potential for emerging carbon and biodiversity markets to incentivise private investment in wetland conservation and restoration. Our Systematic Literature Review assessed impacts of cattle, pigs, horses, deer, buffalo, sheep, camels, and other ungulates on wetlands. There were 372 relevant resources from 35 countries, with highest representation from Australia and the United States. The majority related to cattle (29 %) and pigs (19 %). More impacts were reported in freshwater wetlands (51 %) than marine (19 %). A quarter of studies related to riparian habitats. Ungulate impacts varied geographically and among climates. More studies reported soil damage, weed dispersal, decreased vegetation cover, and woody vegetation suppression than neutral or positive changes in these metrics. Decreases in richness and abundance of native flora and fauna were more frequently reported than increases. Of 33 studies reporting wetland carbon impacts, 24 reported increased CO2 emissions due to loss of soil carbon or vegetation biomass. Ungulate exclusion from wetlands could enhance carbon stocks and biodiversity, however further studies comparing wetland typologies and carbon dynamics are needed to quantify levels of enhancement given differences in ungulate species and environments.

期刊论文 2024-02-01 DOI: 10.1016/j.biocon.2023.110432 ISSN: 0006-3207

Context. Sus scrofa is a species that easily adapts to diverse environments and climatic zones. In urban and suburban spaces, its presence negatively impacts soil, crops, and animal production, posing health risks for other animals and even humans. Declared a national pest in Uruguay, it is one of the main predators of sheep. A deeper knowledge of its habitat, current distribution, and the environmental factors that influence its locations is required to develop an adequate programme to control its population. Aims. To determine the spatial distribution of wild boars in Uruguay and its association with environmental factors concerning livestock production, on the basis of a survey administered to farmers. Methods. The survey was completed by 2360 farmers, gathering information on the presence of wild boars and other wildlife animals on their farms, methods used for wild boar control, economic damages caused by the species, number of sheep, and types of land-cover besides pastures (native woodlands, shelter forests, pine plantations, and eucalyptus plantations). Key results. Farms located in the Northeast region, with native woodlands and/or pine plantations, and larger than 500 ha were more likely to report the presence of wild boars. The presence of eucalyptus plantations did not affect the presence of wild boars in any region of the country. While the presence of sheep, free- ranging dogs, or wild boars on neighbouring farms affected the presence of wild boars, the existence of eucalyptus plantations showed no effect across any region of the country. On the other hand, the presence of wild boars increased in association with the presence of pampas foxes (Lycalopex gymnocercus). Conclusions. These results provide valuable information regarding the current distribution of an invasive exotic ungulate, and factors influencing the probability of reporting its presence.

期刊论文 2024-01-01 DOI: 10.1071/WR23125 ISSN: 1035-3712

Insects are highly successful animals inhabiting marine, freshwater and terrestrial habitats from the equator to the poles. As a group, insects have limited ability to regulate their body temperature and have thus required a range of strategies to support life in thermally stressful environments, including behavioural avoidance through migration and seasonal changes in cold tolerance. With respect to overwintering strategies, insects have traditionally been divided into two main groups: freeze tolerant and freeze avoiding, although this simple classification is underpinned by a complex of interacting processes, i.e. synthesis of ice nucleating agents, cryoprotectants, antifreeze proteins and changes in membrane lipid composition. Also, in temperate and colder climates, the overwintering ability of many species is closely linked to the diapause state, which often increases cold tolerance ahead of temperature-induced seasonal acclimatisation. Importantly, even though most species can invoke one or both of these responses, the majority of insects die from the effects of cold rather than freezing. Most studies on the effects of a changing climate on insects have focused on processes that occur predominantly in summer (development, reproduction) and on changes in distributions rather than winter survival per se. For species that routinely experience cold stress, a general hypothesis would be that predicted temperature increases of 1 degrees C to 5 degrees C over the next 50-100 years would increase winter survival in some climatic zones. However, this is unlikely to be a universal effect. Negative impacts may occur if climate warming leads to a reduction or loss of winter snow cover in polar and sub-polar areas, resulting in exposure to more severe air temperatures, increasing frequency of freeze-thaw cycles and risks of ice encasement. Likewise, whilst the dominant diapause-inducing cue (photoperiod) will be unaffected by global climate change, higher temperatures may modify normal rates of development, leading to a de-coupling of synchrony between diapause-sensitive life-cycle stages and critical photoperiods for diapause induction. In terms of climate warming and potential heat stress, the most recent predictions of summer temperatures in Europe of 40 degrees C or higher in 50-75 years, are close to the current upper lethal limit of some insects. Long-term data sets on insect distributions and the timing of annual migrations provide strong evidence for 'positive' responses to higher winter temperatures over timescales of the past 20-50 years in North America, Europe and Asia.

期刊论文 2010-03-15 DOI: 10.1242/jeb.037911 ISSN: 0022-0949
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