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1.
Arch Insect Biochem Physiol ; 109(2): e21861, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34904747

RESUMEN

The red imported fire ant (RIFA), Solenopsis invicta Buren is native to South America and known as a global problematic invasive species. At low temperatures, several investigations have demonstrated an increase in glycerol as a primary rapid cold hardening (RCH) component and an increase in the supercooling point. Two genes, glycerol-3-phosphate dehydrogenase (GPDH) and glycerol kinase (GK), have been identified as being involved in the glycerol production process. In this study, one GPDH and two GK sequences were extracted from RIFA transcriptome analysis (Si-GPDH, Si-GK1, and Si-GK2). All three genes were expressed in different body parts and different tissues of S. invicta that Si-GK2 showed a higher expression level than the others. According to gene expression levels by qRT-PCR analysis, the highest expression levels of three genes were observed in fat body tissues. After 1 h of exposure to low temperatures (5°C or lower), the mRNA levels of these genes significantly increased, according to expression analyses. RNA interference (RNAi) of Si-GPDH or Si-GK1 and Si-GK2 exhibited a significant downregulation at the mRNA level. The mortality rate of treated RIFA by double-stranded RNA (dsRNA) specific to GPDH and GK2 significantly increased at low temperatures. This study indicates that GPDH and GK2 as glycerol biosynthesis genes in RIFA have a high expression level to synthesize a high level of glycerol as an RCH factor and they play crucial roles in survival during the cold period.


Asunto(s)
Hormigas , Animales , Hormigas/genética , Frío , Glicerol , Especies Introducidas , ARN Bicatenario
2.
J Environ Manage ; 302(Pt A): 113929, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34688048

RESUMEN

The introduction of invasive crayfish has led to a decline of many European native species of crayfish across their range. In this study, novel duplex assays for all crayfish occurring in Switzerland were developed. We aimed to identify the distribution of the seven species using a traditional trap surveillance method as well by collecting water samples to detect eDNA by species-specific quantitative real-time PCR. We reveal our overall experience in finding optimal field and laboratory techniques to discover the distribution and abundance of native and invasive species in order to enhance knowledge of early invasive species invasion and highlight important pockets of populations where native species remain, for implementation of conservation strategies. Using eDNA, important populations of native noble and white-clawed crayfish were revealed in multiple waters across various cantons. The successful identification of native and invasive crayfish species in Switzerland using eDNA can be applied to future nationwide projects. This method which has the ability to detect all species simultaneously across an entire country, will allow an improvement in freshwater crayfish conservation management.


Asunto(s)
Astacoidea , Especies Introducidas , Animales , Astacoidea/genética , Agua Dulce , Alimentos Marinos , Suiza
3.
Sci Total Environ ; 806(Pt 3): 151318, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34743879

RESUMEN

The United States has thousands of invasive species, representing a sizable, but unknown burden to the national economy. Given the potential economic repercussions of invasive species, quantifying these costs is of paramount importance both for national economies and invasion management. Here, we used a novel global database of invasion costs (InvaCost) to quantify the overall costs of invasive species in the United States across spatiotemporal, taxonomic, and socioeconomic scales. From 1960 to 2020, reported invasion costs totaled $4.52 trillion (USD 2017). Considering only observed, highly reliable costs, this total cost reached $1.22 trillion with an average annual cost of $19.94 billion/year. These costs increased from $2.00 billion annually between 1960 and 1969 to $21.08 billion annually between 2010 and 2020. Most costs (73%) were related to resource damages and losses ($896.22 billion), as opposed to management expenditures ($46.54 billion). Moreover, the majority of costs were reported from invaders from terrestrial habitats ($643.51 billion, 53%) and agriculture was the most impacted sector ($509.55 billion). From a taxonomic perspective, mammals ($234.71 billion) and insects ($126.42 billion) were the taxonomic groups responsible for the greatest costs. Considering the apparent rising costs of invasions, coupled with increasing numbers of invasive species and the current lack of cost information for most known invaders, our findings provide critical information for policymakers and managers.


Asunto(s)
Ecosistema , Especies Introducidas , Agricultura , Animales , Costo de Enfermedad , Costos de la Atención en Salud , Insectos , Estados Unidos
4.
Acta Trop ; 225: 106226, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34752781

RESUMEN

Vectors and intermediate hosts of globally impactful human parasites are sensitive to changes in the ecological communities in which they are embedded. Sites of endemic transmission of human schistosome can also be invaded by nonnative species, especially aquatic plants (macrophytes). We tested the effects on macrophyte invasions on experiment snail and schistosome populations created in 100 L mesocosm tanks. We established macrophyte-free mesocosms and those containing one of four widespread macrophyte species that are inedible to snails (duckweed, hornwort, water lettuce, or water hyacinth) and then tracked edible resources (periphyton algae) and the abundance, reproduction, and infection of snail intermediate hosts for 16 weeks. We predicted that the three floating macrophytes would reduce periphyton, thereby reducing snail reproduction, abundance, and infections. In contrast, we predicted that hornwort, which is submerged and provides substrate for periphyton growth, would increase snail reproduction and abundance. As predicted, all floating macrophytes decreased periphyton, but only water hyacinth significantly decreased snail reproduction and abundance. Snail abundance increased significantly only with water lettuce. We hypothesize that this unanticipated increase in snails occurred because water lettuce produced abundant and/or high quality detritus, subsidizing snails despite low periphyton availability. Unfortunately, we detected too few infections to analyze. Aquatic macrophytes exert strong species-specific effects on snail populations. Therefore, efforts to manage invasive plants in endemic sites should evaluate changes in resources, snails, and transmission potential. We recommend caution with management efforts that produce large amounts of detritus, which might stimulate snail populations and therefore risk of human exposure.


Asunto(s)
Biomphalaria , Plantas , Schistosoma mansoni , Animales , Biomphalaria/crecimiento & desarrollo , Biomphalaria/parasitología , Especies Introducidas , Dinámica Poblacional
5.
J Environ Manage ; 302(Pt B): 114051, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34773778

RESUMEN

Land-use change, and associated land clearing/conversion and fragmentation are major drivers of biodiversity decline across the globe. The spread of invasive species is a well-recognised consequence of land-use change. The extent and intensity of invasion however is often difficult to assess due to a lack of temporal data. Using detailed mapping information for 130, 950 km2 of sub-coastal Queensland, Australia and results from field surveys we investigated changes to land-use, the extent of remnant (intact) vegetation and the spread of prominent invasive plant species over time (1997-2018). In the 50 years prior to 1997 the area underwent significant land development (mostly for livestock grazing and crops), resulting in a reduction of 45% of its remnant vegetation. Despite key policy developments aimed at protecting the remaining vegetation and species, 7392 km2 was cleared/converted between 1997 and 2017, mainly for the expansion of grazing and cropping lands. Vegetation types specifically listed for national protection under these policies were some of the greatest affected, highlighting the need for improved implementation and regulation of these control measures. Within remaining fragments of remnant vegetation, the cover and presence of two invasive perennial grass species indian couch (Bothriochloa pertusa) and buffel grass (Cenchrus ciliaris) increased significantly during this time period. There was also a moderate increase in the cover and presence of the annual herb Parthenium weed (Parthenium hysterophorus). The spread of these species within the landscape likely reflects an 'invasion debt', incurred from an intense history of land-use within the region and we predict this trend will continue to threaten remnant ecosystems.


Asunto(s)
Biodiversidad , Ecosistema , Australia , Conservación de los Recursos Naturales , Especies Introducidas , Malezas
6.
Glob Chang Biol ; 28(1): 267-284, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34614268

RESUMEN

Exotic plant invasions alter ecosystem properties and threaten ecosystem functions globally. Interannual climate variability (ICV) influences both plant community composition (PCC) and soil properties, and interactions between ICV and PCC may influence nitrogen (N) and carbon (C) pools. We asked how ICV and non-native annual grass invasion covary to influence soil and plant N and C in a semiarid shrubland undergoing widespread ecosystem transformation due to invasions and altered fire regimes. We sampled four progressive stages of annual grass invasion at 20 sites across a large (25,000 km2 ) landscape for plant community composition, plant tissue N and C, and soil total N and C in 2013 and 2016, which followed 2 years of dry and wet conditions, respectively. Multivariate analyses and ANOVAs showed that in invasion stages where native shrub and perennial grass and forb communities were replaced by annual grass-dominated communities, the ecosystem lost more soil N and C in wet years. Path analysis showed that high water availability led to higher herbaceous cover in all invasion stages. In stages with native shrubs and perennial grasses, higher perennial grass cover was associated with increased soil C and N, while in annual-dominated stages, higher annual grass cover was associated with losses of soil C and N. Also, soil total C and C:N ratios were more homogeneous in annual-dominated invasion stages as indicated by within-site standard deviations. Loss of native shrubs and perennial grasses and forbs coupled with annual grass invasion may lead to long-term declines in soil N and C and hamper restoration efforts. Restoration strategies that use innovative techniques and novel species to address increasing temperatures and ICV and emphasize maintaining plant community structure-shrubs, grasses, and forbs-will allow sagebrush ecosystems to maintain C sequestration, soil fertility, and soil heterogeneity.


Asunto(s)
Carbono , Poaceae , Ecosistema , Especies Introducidas , Nitrógeno , Suelo
7.
J Environ Manage ; 301: 113779, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34597945

RESUMEN

The Ballast Water Management Convention can decrease the introduction risk of harmful aquatic organisms and pathogens, yet the Convention increases shipping costs and causes subsequent economic impacts. This paper examines whether the Convention generates disproportionate invasion risk reduction results and economic impacts on Small Island Developing States (SIDS) and Least Developed Countries (LDCs). Risk reduction is estimated with an invasion risk assessment model based on a higher-order network, and the effects of the regulation on national economies and trade are estimated with an integrated shipping cost and computable general equilibrium modeling framework. Then we use the Lorenz curve to examine if the regulation generates risk or economic inequality among regions. Risk reduction ratios of all regions (except Singapore) are above 99%, which proves the effectiveness of the Convention. The Gini coefficient of 0.66 shows the inequality in risk changes relative to income levels among regions, but risk reductions across all nations vary without particularly high risks for SIDS and LDCs than for large economies. Similarly, we reveal inequality in economic impacts relative to income levels (the Gini coefficient is 0.58), but there is no evidence that SIDS and LDCs are disproportionately impacted compared to more developed regions. Most changes in GDP, real exports, and real imports of studied regions are minor (smaller than 0.1%). However, there are more noteworthy changes for select sectors and trade partners including Togo, Bangladesh, and Dominican Republic, whose exports may decrease for textiles and metal and chemicals. We conclude the Convention decreases biological invasion risk and does not generate disproportionate negative impacts on SIDS and LDCs.


Asunto(s)
Países en Desarrollo , Agua , Especies Introducidas , Navíos , Abastecimiento de Agua
8.
Parasitol Int ; 86: 102475, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34610466

RESUMEN

Ankylocythere sinuosa (Rioja, 1942), a symbiotic ostracod native to North America, was found from the Japanese mitten crab Eriocheir japonica (De Haan, 1835), a species native to Japan, collected from a pond in Shizuoka City, Shizuoka Prefecture, central Japan. Introduced North American crayfish Procambarus clarkii (Girard, 1852), which is a host of A. sinuosa in their native range, inhabits ponds sympatrically with Japanese mitten crabs, and it is thought that the ostracods transferred from the exotic crayfish to the native crabs. In recent years, along with the artificial transportation of crayfish around the world, their symbiotic ostracods also have been found on the body surfaces of exotic crayfish in Europe and Japan. However, no studies have confirmed the infestation of exotic ostracods on native crustaceans in the field. A wide range of developmental stages of A. sinuosa from juveniles to adults were found in Japanese mitten crabs, and mating individuals were also found. This strongly suggests that they can reproduce on the body surface of Japanese mitten crabs. In the future, it will be necessary to strengthen measures against alien species to prevent these exotic symbionts from infestating native ecosystems, and we also need to investigate the exact impact of this symbiont on Japanese mitten crabs.


Asunto(s)
Astacoidea/parasitología , Crustáceos/fisiología , Interacciones Huésped-Parásitos , Especies Introducidas , Simbiosis , Animales , Femenino , Japón , Masculino
9.
J Environ Manage ; 301: 113803, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34626944

RESUMEN

Invasive species alter hydrologic processes at watershed scales, with impacts to biodiversity and the supporting ecosystem services. This effect is aggravated by climate change. Here, we integrated modelled hydrologic data, remote sensing products, climate data, and linear mixed integer optimization (MIP) to identify stewardship actions across space and time that can reduce the impact of invasive species. The study area is the windward coast of Hawai'i Island (USA) across which non-native strawberry guava occurrence varies from extremely dense stands in lower watershed reaches, to low densities in upper watershed forests. We focused on the removal of strawberry guava, an invader that exerts significant impacts on watershed condition. MIP analyses spatially optimized the assignment of effective management actions to increase water yield, generate revenue from enhanced freshwater services, and income from removed biomass. The hydrological benefit of removing guava, often marginal when considered in isolation, was financially quantified, and single- and multiobjective MIP formulations were then developed over a 10-year planning horizon. Optimization resulted in $2.27 million USD benefit over the planning horizon using a payment-for-ecosystem-services scheme. That value jumped to $4.67 million when allowing work schedules with overnight camping to reduce costs. Pareto frontiers of weighted pairs of management goals showed the benefit of clustering treatments over space and time to improve financial efficiency. Values of improved land-water natural capital using payment-for-ecosystem-services schemes are provided for several combinations of spatial, temporal, economical, and ecosystem services flows.


Asunto(s)
Ecosistema , Especies Introducidas , Carbono , Conservación de los Recursos Naturales , Bosques , Agua
10.
Environ Pollut ; 292(Pt B): 118399, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34695515

RESUMEN

Evidence suggests that the invasion of Spartina alterniflora (S. alterniflora) poses potentially serious risks to the stability of coastal wetlands, an ecosystem that is extremely vulnerable to both biological and non-biological threats. However, the effects and mechanisms of sulfur (S) in mediating the growth and expansion of S. alterniflora are poorly understood, particularly when sediments are contaminated with cadmium (Cd). A 6-month greenhouse study was conducted to evaluate the mediating effect of S on Cd tolerance and growth of S. alterniflora. Treatments consisted of a factorial combination of three S rates (applied as Na2SO4; 0, 500, 1000 mg kg-1 dry weight (DW), as S0, S500, and S1000) and four Cd rates (applied as CdCl2; 0, 1, 2, 4 mg kg-1 DW, as Cd0, Cd1, Cd2, and Cd4). Results showed that although the exogenous S supply obviously increased Cd accumulation in roots (up to 71.22 ± 6.43 mg kg-1 DW) due to the decrease of Fe concentration in iron plaque (down to 4.02 ± 1.18 mg g-1 DW), biomass reduction and oxidative stress in plant tissues were significantly alleviated. The addition of S significantly up-regulated the concentration of compounds related to Cd tolerance, including proline and glutathione. Therefore, the translocation of Cd was restricted, and plant growth was not impacted. The present study demonstrated that the exogenous sulfur supply could promote the growth of S. alterniflora and enhance its tolerance to Cd. Therefore, under the effects of S. alterniflora, the increased fluctuations of S pool caused by the release and deposition of S might further exacerbate S. alterniflora expansion in Cd contaminated coastal wetlands.


Asunto(s)
Cadmio , Humedales , Cadmio/toxicidad , China , Ecosistema , Especies Introducidas , Poaceae , Azufre
11.
Sci Total Environ ; 803: 149875, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-34478901

RESUMEN

Invasive alien fishes have had pernicious ecological and economic impacts on both aquatic ecosystems and human societies. However, a comprehensive and collective assessment of their monetary costs is still lacking. In this study, we collected and reviewed reported data on the economic impacts of invasive alien fishes using InvaCost, the most comprehensive global database of invasion costs. We analysed how total (i.e. both observed and potential/predicted) and observed (i.e. empirically incurred only) costs of fish invasions are distributed geographically and temporally and assessed which socioeconomic sectors are most affected. Fish invasions have potentially caused the economic loss of at least US$37.08 billion (US2017 value) globally, from just 27 reported species. North America reported the highest costs (>85% of the total economic loss), followed by Europe, Oceania and Asia, with no costs yet reported from Africa or South America. Only 6.6% of the total reported costs were from invasive alien marine fish. The costs that were observed amounted to US$2.28 billion (6.1% of total costs), indicating that the costs of damage caused by invasive alien fishes are often extrapolated and/or difficult to quantify. Most of the observed costs were related to damage and resource losses (89%). Observed costs mainly affected public and social welfare (63%), with the remainder borne by fisheries, authorities and stakeholders through management actions, environmental, and mixed sectors. Total costs related to fish invasions have increased significantly over time, from

Asunto(s)
Ecosistema , Especies Introducidas , Animales , Europa (Continente) , Explotaciones Pesqueras , Peces , Humanos
12.
Sci Total Environ ; 805: 150314, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-34543797

RESUMEN

Mediterranean islands are considered especially vulnerable to biological invasions by alien plants. However, there is a lack of studies on island scale regarding the factors that determine alien plant's spatial distribution, and the way they affect invasion process. A roadside survey of alien plant species was conducted on Lesvos, the 8th largest island in Mediterranean basin. Data on species counts and explanatory variables were aggregated to a 1 sq. km vector grid and brought together into a single GIS layer. Alien species counts were modelled by using a Negative-binomial model while a Generalised Additive Model was used to examine possible non-linear relationships to the predictors by using splines. A subset of significant factors, related both to human activities and the environment, shaped the spatial distribution of aliens and influenced, in various ways, their future invasion outcome. Transformed areas with high levels of anthropogenic pressures and disturbances, including high population numbers, dense road network, ports, and intensive land use, as is the case for coastal zones, promoted the presence of alien species. Contrary, modified areas, such as grazed lands, seemed to restrict alien species occurrences, possibly due to the long grazing history these areas present, a regime in which aliens are not adapted. Alien plants presence was positively associated with high levels of NPP, diversity of geological substrates, and a west-facing aspect. Anthropogenic determinants of alien spatial patterns were primarily connected to increased propagule pressure, whereas environmental factors demonstrated the preference of alien plants for resource-rich environments.


Asunto(s)
Especies Introducidas , Plantas , Adaptación Fisiológica , Ecosistema , Humanos , Islas del Mediterráneo
13.
Ying Yong Sheng Tai Xue Bao ; 32(12): 4499-4507, 2021 Dec.
Artículo en Chino | MEDLINE | ID: mdl-34951291

RESUMEN

Spartina alterniflora was introduced into the Yellow River Delta (YRD) in 1990 with the purpose of shore protection and siltation accretion. However, it spread rapidly and became a severe threat to the local coastal wetland ecosystem. To assess the impacts of S. alterniflora invasion on the benthic food web, we sampled the potential food sources of macrobenthos in November 2020, analyzed the trophic level and the benthic food web structure based on stable isotope technique. Results showed that the average δ13C values of macrobenthic food sources followed an order: sediment organic matter (SOM) > S. alterniflora > benthic microalgae > particulate organic matter (POM) > Suaeda salsa. The average δ15N values significantly differed among food sources, ranging from 1.24‰ to 9.03‰. The trophic levels of different macrobenthos ranged from 1.73 to 4.19, of which the bivalve species was the lowest one. S. alterniflora and the decayed debris were the most important food sources for macrobenthos, but without any impact on the trophic level structure of macro-benthos. In conclusion, Spartina alterniflora invasion distinctly changed the composition of food sources of macrobenthos through a "bottom-up" effect, which would probably impact the local food web structure in the YRD wetland.


Asunto(s)
Ecosistema , Cadena Alimentaria , China , Especies Introducidas , Poaceae , Ríos , Humedales
14.
Proc Natl Acad Sci U S A ; 118(51)2021 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-34911766

RESUMEN

Invasion rates have increased in the past 100 y irrespective of international conventions. What characterizes a successful invasion event? And how does genetic diversity translate into invasion success? Employing a whole-genome perspective using one of the most successful marine invasive species world-wide as a model, we resolve temporal invasion dynamics during independent invasion events in Eurasia. We reveal complex regionally independent invasion histories including cases of recurrent translocations, time-limited translocations, and stepping-stone range expansions with severe bottlenecks within the same species. Irrespective of these different invasion dynamics, which lead to contrasting patterns of genetic diversity, all nonindigenous populations are similarly successful. This illustrates that genetic diversity, per se, is not necessarily the driving force behind invasion success. Other factors such as propagule pressure and repeated introductions are an important contribution to facilitate successful invasions. This calls into question the dominant paradigm of the genetic paradox of invasions, i.e., the successful establishment of nonindigenous populations with low levels of genetic diversity.


Asunto(s)
Ctenóforos/genética , Variación Genética , Genómica , Distribución Animal , Animales , Ctenóforos/fisiología , Genoma , Especies Introducidas
15.
Zootaxa ; 5060(4): 515-532, 2021 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-34810651

RESUMEN

The checklist of scale insect species recorded from Kenya comprises 14 families, 128 genera and 304 species, of which 207 (68.0%) are probably of African origin, 91 (29.9%) have been introduced from outside Africa and six (2.0%) are of unknown origin. Out of the 207 African species, only 11 (5.3%) have been recorded damaging plants, whereas out of the 91 introduced species, 45 (49.5%) have caused or are highly likely to cause plant damage in Kenya. The most economically important scale insect families in Kenya are (in order of importance) the Pseudococcidae, Coccidae and Diaspididae. Four new combinations are made: Eurycoccus glomerulus De Lotto is transferred to Trionymus, as Trionymus glomerulus (De Lotto) comb. n.; Trionymus sativus James is transferred to Paracoccus, as Paracoccus sativus (James) comb. n.; Pseudococcus masakensis James is transferred to Nipaecoccus as Nipaecoccus masakensis (James) comb. n., and Spilococcus commiphorae De Lotto is transferred to Paracoccus, as Paracoccus commiphorae (De Lotto) comb. n.


Asunto(s)
Hemípteros , Animales , Especies Introducidas , Kenia
16.
Zootaxa ; 5060(3): 429-438, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34810656

RESUMEN

We provide the first confirmed record of Halyomorpha picus (Fabricius, 1794) (Hemiptera: Heteroptera: Pentatomoidea: Pentatomidae: Pentatominae: Cappaeini) from Pakistan: Islamabad Capital Territory, and provide habitus photographs and electron scanning micrographs of the male genitalia of the voucher specimens. Two species previously described from Pakistan are found to fit within the morphological variability of H. picus and the following two junior subjective synonyms are proposed: Halyomorpha picus (Fabricius, 1794) = Halyomorpha punjabensis Ahmad Kamaluddin, 1977, syn. nov., = Halyomorpha azhari Ahmad Zaidi, 1989, syn. nov. The record of Halyomorpha scutellata Distant, 1879, from Pakistan by Sharif et al. (2020) is based on misidentification of a species of Neohalys Ahmad Perveen, 1982 (Pentatominae: Halyini) and excluded from Pakistan fauna. Based on the analysis of female genitalia figures provided by Gadalla (2004), the record of H. picus from Egypt represents a misidentification of H. halys Stl, 1855, which extends the distribution of that invasive species to North Africa.


Asunto(s)
Hemípteros , Heterópteros , Animales , Femenino , Especies Introducidas , Masculino , Pakistán
17.
PLoS One ; 16(10): e0258150, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34618833

RESUMEN

Bigheaded Carp have spread throughout the Mississippi River basin since the 1970s. Little has stopped the spread as carp have the ability to pass through locks and dams, and they are currently approaching the Great Lakes. However, the location of the leading edge in the Illinois River has stalled for over a decade, even though there is no barrier preventing further advancement towards the Great Lakes. Defining why carp are not moving towards the Great Lakes is important for predicting why they might advance in the future. The aim of this study was to test the hypothesis that anthropogenic contaminants in the Illinois River may be playing a role in preventing further upstream movement of Bigheaded Carp. Ninety three livers were collected from carp at several locations between May and October of 2018. Liver samples were analyzed using gas chromatography-mass spectrometry in a targeted metabolite profiling approach. Livers from carp at the leading edge had differences in energy use and metabolism, and suppression of protective mechanisms relative to downstream fish; differences were consistent across time. This body of work provides evidence that water quality is linked to carp movement in the Illinois River. As water quality in this region continues to improve, consideration of this impact on carp spread is essential to protect the Great Lakes.


Asunto(s)
Migración Animal/fisiología , Carpas/metabolismo , Ecosistema , Metabolómica , Animales , Carpas/fisiología , Monitoreo del Ambiente/métodos , Humanos , Illinois , Especies Introducidas , Lagos , Mississippi , Ríos , Alimentos Marinos
18.
Glob Chang Biol ; 27(23): 6129-6138, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34614545

RESUMEN

There is growing acknowledgement that human-induced change can push ecosystems beyond tipping points, resulting in the dramatic and sudden loss of vital ecosystem services. Invasive non-native species (INNS) are spreading rapidly due to anthropogenic activities and climate change and can drive changes to ecosystem functioning by altering abiotic conditions and restructuring native communities. Shallow lake ecosystems are especially vulnerable to perturbation from INNS as they can exist in two alternative stable states: either clear water with an abundance of vegetation or turbid, unvegetated and dominated by phytoplankton. Through a global meta-analysis of studies observing the effects of INNS on recipient lake ecosystems, we found that certain INNS drive significant changes in the abundance of key taxa and conditions that govern the balance of alternative equilibria in shallow lakes. Invasive fish and crustaceans demonstrated effects likely to lead to early ecosystem collapse to a turbid state and delay ecosystem recovery. Invasive molluscs presented opposite effects, which may delay ecosystem collapse and encourage ecosystem recovery. Our results demonstrate that INNS could significantly alter the tipping points of ecosystem collapse and recovery, and that not all invasive species may initiate system collapse. Our results provide guidance for managers of invaded shallow lake ecosystems, which provide diverse services including sanitation, potable water supply, industrial cooling, aquaculture and recreational resources. Moreover, our approach could be applied to identify key potential drivers of change in other crucial ecosystems which demonstrate alternative equilibria, such as coral reefs and kelp forests.


Asunto(s)
Ecosistema , Lagos , Animales , Cambio Climático , Humanos , Especies Introducidas , Fitoplancton
19.
Oecologia ; 197(3): 757-770, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34622333

RESUMEN

Forecasting the effects of climate change on the distribution of invasive species can be difficult, because invaders often thrive under novel physical conditions and biotic interactions that differ from those in their native range. In this study, we experimentally examined how rising temperatures and sand burial could alter the abundance and biotic interactions of two invasive beachgrasses, Ammophila arenaria and A. breviligulata, along the U.S. Pacific Northwest coast. We asked whether the current geographic ranges of the two congeners, and thus their effects on dune morphology and coastal ecosystem services, might shift as a consequence of climate driven changes in warming and sand supply. Our results show that A. breviligulata had lower biomass and tiller production when exposed to warming and high rates of sand burial, while A. arenaria showed neutral or positive responses to those treatments. Nevertheless, under all experimental combinations, A. breviligulata had strong negative effects on A. arenaria, while A. arenaria had weaker effects on A. breviligulata. Our models predict that although A. breviligulata mostly excludes A. arenaria, elevated temperatures and high rates of sand burial also increase the likelihood of species coexistence. We suggest that under climate change, the differences in physiological tolerance and the mediation of species interactions could expand the northern distributional limit of A. arenaria but restrict the southern limit of A. breviligulata. Moreover, because beachgrass abundance has direct effects on biophysical functions of dunes, reductions in vigor from warming could alter coastal protection, biodiversity, and carbon sequestration.


Asunto(s)
Ecosistema , Poaceae , Biodiversidad , Cambio Climático , Especies Introducidas
20.
Am J Bot ; 108(10): 1902-1916, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34636413

RESUMEN

PREMISE: Biological invasions and climate change are major threats to biodiversity. It is therefore important to anticipate how the climate changes projected for Southern Europe would affect the ecophysiological performance of the invasive South African plant, Carpobrotus edulis (ice plant or sour fig), and its capacity to undergo rapid adaptive evolution. METHODS: We manipulated the climate conditions in a field plot located on the island of Sálvora (northwest of the Iberian Peninsula) to establish a full factorial experiment with C. edulis plants transplanted from four native (southern African) and four invasive (northwestern Iberian Peninsula) populations. Throughout 14 months we measured growth and functional traits of this species under two temperatures (control vs. increased), and two rainfall levels (control vs. reduced). RESULTS: Temperature increased photochemical efficiency and relative growth rate of C. edulis. Rainfall modulated some of the effects of temperature on C and N isotopic composition, and pigment contents. Invasive populations showed lower root mass allocation and higher survival rates, as well as increased water use efficiency, lipid peroxidation, chlorophyll, and xanthophyll cycle pigment contents than native populations. CONCLUSIONS: The increased growth and physiological performances observed under our experimental conditions suggest that the expected climate changes would further promote the invasion of C. edulis. Differences between native and invasive genotypes in survival and functional traits revealed that populations have diverged during the process of invasion, what gives support to the invasiveness hypothesis. Our findings highlight the importance of analyzing intraspecific variability in functional responses to better predict how invasive species will respond to environmental changes.


Asunto(s)
Aizoaceae , Cambio Climático , Especies Introducidas , Plantas , Temperatura
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