Freshwater Biology, Journal Year: 2025, Volume and Issue: 70(2)
Published: Feb. 1, 2025
ABSTRACT Biological invasions in freshwater ecosystems are increasingly severe, posing significant threats to ecosystem health and economic development. Hydrilla verticillata (L.f.) Royle Elodea densa (Planch.) Casp. two of the most aggressive invasive submerged macrophytes worldwide, often regarded as similar species due their growth forms habitat requirements, although there few field coexistence records. is a native large plateau Lake Erhai, where non‐native E. has been documented since 2017. This study aims at exploring colonisation process well its niche overlap interspecific interactions with H. Erhai. A continuous seven‐year investigation was conducted Four indicators were used assess population distribution , including occurrence frequency, biomass, relative abundance breadth. The logistic model applied analyse dynamics. Gaussian characterise water depths. stability index employed evaluate variations measured indices across different Indicators association describe between species. established several stable populations Erhai after years naturalisation, primarily colonising deeper areas lake than . tended thrive depths around 4.0 m, whereas typically grew from 2.0 3.0 m. demonstrated greater varying Niche minimal. Our findings indicated that this lake, exhibited higher competitiveness alien There distinct difference which prevented competitive exclusion. achieved lake‐wide scale. provided first evidence for globally recognized species, showing habitats sufficient environmental gradients filtering pressures, taxonomy appearance could avoid exclusion by occupying ecological niches, leading coexistence.
Language: Английский
Citations
1
Water Air & Soil Pollution, Journal Year: 2022, Volume and Issue: 233(3)
Published: Feb. 25, 2022
Language: Английский
Citations
20
Hydrological Processes, Journal Year: 2022, Volume and Issue: 36(7)
Published: June 15, 2022
Abstract The role of aquatic and riparian vegetation in driving morphodynamics rivers is being increasingly recognized across all river types. Here, we focus on gravel‐bed rivers, where the ability to influence depends upon retention stabilization predominantly sand finer sediments build landforms within active channel. One aspect such interactions among vegetation, flows transported that has received little research attention their contribution within‐channel storage fine sediment as a potentially important component budget reaches catchments. In this article, assemble some preliminary estimates retained by channels four (12 reaches) representing wide range planform (near‐straight, meandering, braided), width (6–800 m), gradient (0.0008–0.004) Q 2 flood (2–1100 m 3 s −1 ), including submerged emergent macrophytes trees shrubs act physical ecosystem engineers. Our results indicate can retain sizeable quantities sediment, ranging from 480 >3000 kg −2 vegetation‐engineered landforms, equivalent 20–1000 when averaged entire channel area. Vegetation retains virtually stored bed surface these channels, increasing 78% lowest energy 100% highest investigated, with major differences locations vegetated stores according style unit stream power. These suggest an budgets well contributing hydrological, geomorphological ecological functioning rivers.
Language: Английский
Citations
18
The Science of The Total Environment, Journal Year: 2025, Volume and Issue: 975, P. 179282 - 179282
Published: April 5, 2025
Lowland shallow lakes are the receiving environments of nutrients and organic carbon from catchment area. In temperate areas, synergic action mild temperatures induce emissions these systems. However, this trend might be modulated by trophic state their productivity. study, we consider blooms invasive submerged aquatic vegetation (SAV) cyanobacteria as a valuable proxy for eutrophication explore role in pools associated budgets lakes. We calculated mass budget two large lakes, characterized different states colonized varying degrees SAV cyanobacteria, basing on annual (input, output, gas exchange, burial) metabolism. The oligo-mesotrophic lake behaved an CO2 CH4 source toward atmosphere (81.2 ± 14.8 g C m-2 yr-1), mainly due to dominant benthic heterotrophic metabolism, whereas mesotrophic sink (-6.7 9.7 because much higher net uptake cyanobacteria. lake, fast-growing metabolism primary producers also resulted strong buffer capacity with respect export lake. Our study highlights major played littoral lacustrine zones control regional/global cycle, especially densely vegetated suggest that interplay between biological invasions can switch sink.
Language: Английский
Citations
0
San Francisco Estuary and Watershed Science, Journal Year: 2023, Volume and Issue: 20(4)
Published: Feb. 3, 2023
Conversion of wetlands in the Sacramento–San Joaquin Delta beginning mid-1800s resulted a pronounced shift from wetland-dominated food web to one driven by open-water primary producers. Submersed and floating aquatic vegetation (SAV FAV) now rank highest potential net production (NPP) among producer groups, provide comparable amount carbon detrital as marshes. However, important details this contribution that relate shifts species composition habitat extent were not understood. Here, we review how changes influence NPP trophic support historical modern periods, within period (the last 2 decades), under future management climate scenarios. We estimate SAV FAV during was approximately half today, before increases open water introduction highly productive primrose. During 20 years), high interannual variability relative has significant variation total NPP. This recent temporal is 6 13 times larger than projected scenarios modeled, including reduction 20% through control measures, substantial wetland restoration (and thus increased channel area could FAV), salinity intrusion western with warming, which favors native greater tolerance. Large swings cascade degree flows consumers pathways herbivory. volatility inconsistency webs make achieving goals for Delta—which lead recovery portion lost since times—even more imperative.
Language: Английский
Citations
7
San Francisco Estuary and Watershed Science, Journal Year: 2023, Volume and Issue: 20(4)
Published: Feb. 3, 2023
Substantial increases in non-native aquatic vegetation have occurred the upper San Francisco Estuary over last 2 decades, largely from explosive growth of a few submerged and floating plant species. Some these species act as ecosystem engineers by creating conditions that favor their further expansion well modifying habitat for other organisms. Over decade, numerous studies investigated patterns turn-over species; effects on health, water quality, habitat; particular or communities physical processes such carbon sediment dynamics. Taking synthetic approach to evaluate what has been learned years shed light just how significant are ecosystems Sacramento-San Joaquin Delta. Aquatic affects every aspect biotic environment, acting landscape. Furthermore, constantly changing across space time, leaving many unanswered questions about full Delta future may result, shift distribution new introduced. Remaining knowledge gaps underlie our understanding macrophyte ecosystems, including roles relationships with respect nutrients nutrient cycling, evapotranspiration budgets, sediment, emerging fish habitats. This paper explores current (SAV FAV) ecology major communities, observed change, interactions between factors affect services disservices within Estuary.
Language: Английский
Citations
7
San Francisco Estuary and Watershed Science, Journal Year: 2023, Volume and Issue: 20(4)
Published: Feb. 3, 2023
The aquatic landscapes of the Sacramento–San Joaquin Delta (hereafter, Delta) and Suisun Bay represent both a significant past future soil carbon stock. Historical alterations hydrologic flows have led to depletion stocks via emissions dioxide (CO2), loss elevation as result subsidence. Optimizing ecosystem hydrology in could reduce reverse subsidence while also providing opportunities for climate mitigation adaptation. Emissions greenhouse gases (GHGs)—notably CO2, methane (CH4 ), nitrous oxide (N2O)—contribute global warming at different rates intensities, requiring GHG accounting modeling assess relative benefits management options. Decades data collection, model building, map development suggest that current actions caused—and can mitigate—losses carbon. We review here magnitude potential offsets, options may be achievable, trade-offs storage under land management. Using land-use/land-cover framework these options, we describe three interventions (impoundment subsidence, agricultural management, tidal reintroduction and/or maintained connectivity), acreage radiative balance clarify their influence on region’s today relation its millennial history. From floodplains farming floating vegetation, find specific scalable strategies manage alter regional balance. Preservation restoration net atmospheric CO2 fluxes into soils are primary route negative Bay, with CH4 emission occurring supporting role. Over 40-year horizon climate-mitigation markets, resilience habitats introduces most uncertainty, from expected unexpected changes associated land, ocean, operational water flows.
Language: Английский
Citations
5
Biological Invasions, Journal Year: 2023, Volume and Issue: 25(6), P. 1827 - 1843
Published: Feb. 25, 2023
Abstract Invasive aquatic macrophytes are a major threat to estuarine ecosystems globally, posing difficult control challenges for resource managers. This study examined the efficacy of fluridone treatment program invasive submerged vegetation (SAV). We leveraged four datasets examine in Sacramento–San Joaquin Delta, freshwater tidal estuary California, from 2014 2018. Annual SAV coverage maps derived spectroscopy data were used conjunction with application and water current speed predicted by 3-D hydrodynamic model system. Our objective was determine if probability occurrence treated sites significantly different untreated sites. whether influenced amount herbicide applied at site, local speed, history site. found that positively associated per unit area, but this effect mediated negative association speed. The did not improve when site multiple consecutive years. Finally, we detect legacy effects one year after cessation treatment. results suggest need careful selection ensure is likely have significant impact given speeds. underscores development additional methodologies hydrologically dynamic systems such as estuaries, particularly needed year-round
Language: Английский
Citations
5
Water Resources Research, Journal Year: 2021, Volume and Issue: 57(8)
Published: July 14, 2021
Abstract We present a field study combining measurements of vegetation density, vegetative drag, and reduction suspended‐sediment concentration (SSC) within patches the invasive submerged aquatic plant Egeria densa . Our was motivated by concern that sediment trapping E. , which has proliferated in Sacramento–San Joaquin Delta, is impacting marsh accretion reducing turbidity. In freshwater tidal occupies shallow regions frequently along channel margins. investigated two sites: Lindsey Slough, muddy low‐energy backwater, lower Mokelumne River, with stronger currents sandy bed sediments. At sites, biomass frontal area, areal density (SAV) were similar. Current attenuation exceeded 90% drag coefficient followed where stem Reynolds number. The SAV reduced SSC an average 18% Slough. River ranged 0%–40%, greatest when discharge elevated. This depletion decreases transport to marshes same percentage, as rising tide must pass through fringing before reaching marshes. Sediment Delta limited low flux canopy settling velocity suspended (mostly flocculated mud). potential reduce SSC, but magnitude sign effect can vary local factors including coverage depositional or erosional nature setting.
Language: Английский
Citations
12
Environmental and Experimental Botany, Journal Year: 2021, Volume and Issue: 188, P. 104520 - 104520
Published: May 15, 2021
Language: Английский
Citations
11