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Guihua Liu - One of the best experts on this subject based on the ideXlab platform.
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functional traits of Submerged Macrophytes in eutrophic shallow lakes affect their ecological functions
Science of The Total Environment, 2021Co-Authors: Han Liu, Guihua Liu, Wei XingAbstract:Abstract Trait-based approaches have been widely used to explore the relationships between Submerged Macrophytes and their surrounding environments. However, the effects of functional traits on ecological functions of Submerged Macrophytes in eutrophic lakes are still not well understood. Here, 1745 individuals of eight dominant Submerged macrophyte species in 19 Yangtze floodplain lakes were collected and classified as needle-leaf (Myriophyllum spicatum, Ceratophyllum demersum, Stuckenia pectinatus, Najas minor) or flat-leaf (Vallisneria natans, Hydrilla verticillata, Potamogeton wrightii, Potamogeton maackianus) types according to photosynthetic trait-based cluster analysis. The flat-leaf type Submerged Macrophytes possessed greater photosynthetic (e.g. higher Fv/Fm) and morphological traits (e.g. higher SLA), while the needle-leaf types held greater stoichiometric traits (e.g. higher plant N/P). Moreover, the RDA analysis indicated that water depth (distribution depth of Submerged Macrophytes) was the key factor influencing functional traits of flat-leaf types, while it was water quality (e.g. WTP and WChl a) for the needle-leaf types. Furthermore, the flat-leaf types showed better performance in improving underwater light conditions (e.g. SD, Kd, Zeu/WD and Red/Blue) and water quality (e.g. WChl a and TSM). Additionally, distribution depth (WD) of the flat-leaf types was shallower than the needle-leaf types in eutrophic shallow lakes along the middle-lower reaches of the Yangtze River. Our study highlights that functional traits of Submerged Macrophytes in eutrophic shallow lakes affect their ecological functions.
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effect of Submerged Macrophytes on metal and metalloid concentrations in sediments and water of the yunnan plateau lakes in china
Journal of Soils and Sediments, 2017Co-Authors: Wei Xing, Guoliang Bai, Han Liu, Guihua LiuAbstract:Submerged Macrophytes have an ability to absorb metals and metalloids either from the sediments via the roots, from the water by the leaves, or from both sources. The objectives of this study were (1) to test the hypothesis that metal and metalloid concentrations in water and sediments from sampling sites with Submerged Macrophytes are significantly lower than those from sampling sites without Submerged Macrophytes, (2) to explore the accumulation potential for metals and metalloids of different Submerged macrophyte species, and (3) to discuss the relationships among Submerged Macrophytes, water, and sediments in the Yunnan Plateau lakes. Twenty Yunnan Plateau lakes with different trophic levels were selected. Concentrations of 16 metals and metalloids (Al, As, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Se, Sr, and Zn) in Submerged Macrophytes, water, and sediments were determined by using ICP-AES. Relationships among metal and metalloid concentrations in water, sediments, and Submerged Macrophytes were carried out by Pearson correlation analysis. The enrichment factor was calculated as the ratio between the concentration of metals and metalloids in a sediment sample and the soil background value. No significant differences were found in metal and metalloid concentrations in water and sediments between sampling sites with Submerged Macrophytes and sampling sites without Submerged Macrophytes. Moreover, lake water and sediments were mainly contaminated by As, Cr, and Pb. Potamogeton distinctus is a hyperaccumulator of Fe according to the threshold value for Fe hyperaccumulation. Many significantly positive correlations were found among metals and metalloids in Submerged Macrophytes due to co-accumulation. We found significant correlation between Cr in Submerged Macrophytes and Cr in water, and strong positive correlations between As, Cd, and Cu in Submerged Macrophytes and As, Cd, and Cu in corresponding sediments in the Yunnan Plateau lakes. Submerged Macrophytes have no significant effects on metal and metalloid concentrations in sediments and water in all the 20 Yunnan Plateau lakes in the study. However, further studies are necessary to understand the interactions of metals and metalloids in Submerged Macrophytes, water, and sediments.
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trace element stoichiometry of Submerged Macrophytes in yangtze floodplain lakes and yunnan plateau lakes china
Aquatic Sciences, 2017Co-Authors: Wei Xing, Beibei Hao, Han Liu, Guihua LiuAbstract:Trace element balance is a key parameter in ecological stoichiometry. However, little is known about trace element stoichiometry of Submerged Macrophytes. We hypothesized that lake nutrients (N and P) and taxonomy strongly affect tissue trace element (Al, As, Ba, Cd, Co, Cr, Li, Pb and Sr) composition and homeostasis of Submerged Macrophytes in Yangtze floodplain lakes and Yunnan plateau lakes (China). Submerged Macrophytes had Co stoichiometric homeostasis in these two sets of lakes. Moreover, Submerged Macrophytes in Yangtze floodplain lakes had higher Cd stoichiometric homeostasis, whereas Submerged Macrophytes in Yunnan plateau lakes had higher Cr, Li and Pb stoichiometric homeostasis. Lake nutrients altered trace element composition of Submerged Macrophytes as shown by canonical correspondence analysis (CCA). Total nitrogen in water (WTN) positively correlated with tissue As and tissue Cd for all lake types, indicating WTN influenced the concentration and composition of tissue As and tissue Cd in Submerged Macrophytes. Canonical discriminant analysis (CDA) successfully discriminated among Submerged macrophyte taxa, revealing there are significant differences in multielement composition of Submerged Macrophytes among taxonomy. Some similar relationships of taxa and trace elements between Yangtze floodplain lakes and Yunnan plateau lakes indicated that certain families of Submerged Macrophytes accumulate specific elements. Differences in relationships of taxa and trace elements between Yangtze floodplain lakes and Yunnan plateau lakes indicated that trace element composition of Submerged Macrophytes could be affected both by taxonomy and the ambient environment.
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growth rate protein rna ratio and stoichiometric homeostasis of Submerged Macrophytes under eutrophication stress
Knowledge and Management of Aquatic Ecosystems, 2016Co-Authors: Wei Xing, Han Liu, Qingshan Shi, Guihua LiuAbstract:Growth rate hypothesis (GRH) and stoichiometric homeostasis of photoautotrophs have always been questioned. However, little is known about GRH and stoichiometric homeostasis of aquatic plants, especially Submerged Macrophytes. Therefore, we aim to test the GRH and explore stoichiometric homeostasis of four freshwater Submerged Macrophytes under eutrophication stress. At the single species level and the multi-species level, N:P ratios of Potamogeton maackianus , Myriophyllum spicatum , Vallisneria natans and Ceratophyllum demersum had no consistent trends with growth rates. However, protein:RNA ratios of P. maackianus , M. spicatum and V. natans all correlated negatively with growth rates, demonstrating GRH can apply to freshwater Submerged Macrophytes, even though they are threatening by eutrophication stress. Protein:RNA ratios positively correlated with N:P ratios in culture media and tissues in Submerged Macrophytes except in P. maackianus (30d), suggesting effects of varying N:P ratios in culture media on protein:RNA ratios are basically in concert with tissue N:P ratios under short-time eutrophication stress. Stoichiometric homeostasis coefficients (H N:P ) indicated Submerged Macrophytes have weak homeostasis. Stoichiometric homeostasis of V . natans was stronger than those of P. maackianus , M. spicatum and C. demersum . The differences in GRH and homeostasis of the four Submerged Macrophytes may be due to species traits.
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multielement stoichiometry of Submerged Macrophytes across yunnan plateau lakes china
Scientific Reports, 2015Co-Authors: Wei Xing, Qiao Shi, Beibei Hao, Han Liu, Zhixiu Wang, Guihua LiuAbstract:Stoichiometric homeostasis of element composition is one of the central concepts of ecological stoichiometry. We analyzed concentrations of macroelements (C, N, P, Ca, K, Mg, S), microelements (Cu, Fe, Mn, Mo, Ni, Zn) and beneficial elements (Na, Se, Si) in Submerged Macrophytes, water and sediments across 20 Yunnan plateau lakes. We predicted that tissue element composition in Submerged Macrophytes is affected by lake trophic level and taxonomy, and Submerged Macrophytes have weak stoichiometric homeostasis for all above 16 elements. Canonical discriminant analyses successfully discriminated among trophic level groups and taxa groups. Of all the elements, C, N, P and S most effectively discriminated among trophic level groups across 20 lakes, revealing lake trophic level mostly affect tissue macroelement composition in Submerged Macrophytes; while Ca, K and Se most effectively discriminated among Submerged Macrophytes taxa groups, suggesting taxonomy mostly affect compositions of macroelements and beneficial elements in Submerged Macrophytes. In addition, the stoichiometric homeostatic coefficient of 1/HCa:C for all five taxa of Submerged Macrophytes were less than zero, suggesting Submerged Macrophytes in Yunnan plateau lakes have strong Ca stoichiometric homeostasis. Our findings, not only broaden the knowledge of multielement stoichiometric homeostasis, but also help to choose most appropriate lake management strategy.
Wei Xing - One of the best experts on this subject based on the ideXlab platform.
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functional traits of Submerged Macrophytes in eutrophic shallow lakes affect their ecological functions
Science of The Total Environment, 2021Co-Authors: Han Liu, Guihua Liu, Wei XingAbstract:Abstract Trait-based approaches have been widely used to explore the relationships between Submerged Macrophytes and their surrounding environments. However, the effects of functional traits on ecological functions of Submerged Macrophytes in eutrophic lakes are still not well understood. Here, 1745 individuals of eight dominant Submerged macrophyte species in 19 Yangtze floodplain lakes were collected and classified as needle-leaf (Myriophyllum spicatum, Ceratophyllum demersum, Stuckenia pectinatus, Najas minor) or flat-leaf (Vallisneria natans, Hydrilla verticillata, Potamogeton wrightii, Potamogeton maackianus) types according to photosynthetic trait-based cluster analysis. The flat-leaf type Submerged Macrophytes possessed greater photosynthetic (e.g. higher Fv/Fm) and morphological traits (e.g. higher SLA), while the needle-leaf types held greater stoichiometric traits (e.g. higher plant N/P). Moreover, the RDA analysis indicated that water depth (distribution depth of Submerged Macrophytes) was the key factor influencing functional traits of flat-leaf types, while it was water quality (e.g. WTP and WChl a) for the needle-leaf types. Furthermore, the flat-leaf types showed better performance in improving underwater light conditions (e.g. SD, Kd, Zeu/WD and Red/Blue) and water quality (e.g. WChl a and TSM). Additionally, distribution depth (WD) of the flat-leaf types was shallower than the needle-leaf types in eutrophic shallow lakes along the middle-lower reaches of the Yangtze River. Our study highlights that functional traits of Submerged Macrophytes in eutrophic shallow lakes affect their ecological functions.
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periphytic algae mediate interactions between neighbor and target Submerged Macrophytes along a nutrient gradient
Ecological Indicators, 2020Co-Authors: Beibei Hao, Wei XingAbstract:Abstract Interactions between plants will shift between competition and facilitation along environmental stresses, which has already been widely demonstrated in terrestrial ecosystems. Reestablishment of Submerged Macrophytes in eutrophic aquatic ecosystems has been recognized as a pivotal measure in the process of ecological restoration. However, little is known about the interactions between neighbor species and target species of Submerged Macrophytes along a nutrient gradient in freshwater ecosystems. Here, we carried out a mesocosm factorial experiment to investigate the responses of three target species (Potamogeton perfoliatus, Myriophyllum spicatum and Vallisneria natans) to the presence/absence of neighbor species (Potamogeton malaianus) under five nutrient levels. Results showed that the neighbor species has a strong negative effect on the performance of P. perfoliatus, whereas has weak effects on the performances of M. spicatum and V. natans (negative and neutral, respectively). Along the experimental nutrient gradient, the neighborhood effects shifted from facilitation to competition, whereas no significant facilitative effects were found in the study. Strong negative neighborhood effects were found in high nutrient levels due to the higher periphyton biomass. Multiple regression analysis suggested that the neighborhood effects are significantly affected and largely explained by the periphyton attached on target species. Overall, our results suggested that periphyton may be a potential factor mediating the neighborhood effects on restoration of Submerged Macrophytes in eutrophic freshwater ecosystems.
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effect of Submerged Macrophytes on metal and metalloid concentrations in sediments and water of the yunnan plateau lakes in china
Journal of Soils and Sediments, 2017Co-Authors: Wei Xing, Guoliang Bai, Han Liu, Guihua LiuAbstract:Submerged Macrophytes have an ability to absorb metals and metalloids either from the sediments via the roots, from the water by the leaves, or from both sources. The objectives of this study were (1) to test the hypothesis that metal and metalloid concentrations in water and sediments from sampling sites with Submerged Macrophytes are significantly lower than those from sampling sites without Submerged Macrophytes, (2) to explore the accumulation potential for metals and metalloids of different Submerged macrophyte species, and (3) to discuss the relationships among Submerged Macrophytes, water, and sediments in the Yunnan Plateau lakes. Twenty Yunnan Plateau lakes with different trophic levels were selected. Concentrations of 16 metals and metalloids (Al, As, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Se, Sr, and Zn) in Submerged Macrophytes, water, and sediments were determined by using ICP-AES. Relationships among metal and metalloid concentrations in water, sediments, and Submerged Macrophytes were carried out by Pearson correlation analysis. The enrichment factor was calculated as the ratio between the concentration of metals and metalloids in a sediment sample and the soil background value. No significant differences were found in metal and metalloid concentrations in water and sediments between sampling sites with Submerged Macrophytes and sampling sites without Submerged Macrophytes. Moreover, lake water and sediments were mainly contaminated by As, Cr, and Pb. Potamogeton distinctus is a hyperaccumulator of Fe according to the threshold value for Fe hyperaccumulation. Many significantly positive correlations were found among metals and metalloids in Submerged Macrophytes due to co-accumulation. We found significant correlation between Cr in Submerged Macrophytes and Cr in water, and strong positive correlations between As, Cd, and Cu in Submerged Macrophytes and As, Cd, and Cu in corresponding sediments in the Yunnan Plateau lakes. Submerged Macrophytes have no significant effects on metal and metalloid concentrations in sediments and water in all the 20 Yunnan Plateau lakes in the study. However, further studies are necessary to understand the interactions of metals and metalloids in Submerged Macrophytes, water, and sediments.
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trace element stoichiometry of Submerged Macrophytes in yangtze floodplain lakes and yunnan plateau lakes china
Aquatic Sciences, 2017Co-Authors: Wei Xing, Beibei Hao, Han Liu, Guihua LiuAbstract:Trace element balance is a key parameter in ecological stoichiometry. However, little is known about trace element stoichiometry of Submerged Macrophytes. We hypothesized that lake nutrients (N and P) and taxonomy strongly affect tissue trace element (Al, As, Ba, Cd, Co, Cr, Li, Pb and Sr) composition and homeostasis of Submerged Macrophytes in Yangtze floodplain lakes and Yunnan plateau lakes (China). Submerged Macrophytes had Co stoichiometric homeostasis in these two sets of lakes. Moreover, Submerged Macrophytes in Yangtze floodplain lakes had higher Cd stoichiometric homeostasis, whereas Submerged Macrophytes in Yunnan plateau lakes had higher Cr, Li and Pb stoichiometric homeostasis. Lake nutrients altered trace element composition of Submerged Macrophytes as shown by canonical correspondence analysis (CCA). Total nitrogen in water (WTN) positively correlated with tissue As and tissue Cd for all lake types, indicating WTN influenced the concentration and composition of tissue As and tissue Cd in Submerged Macrophytes. Canonical discriminant analysis (CDA) successfully discriminated among Submerged macrophyte taxa, revealing there are significant differences in multielement composition of Submerged Macrophytes among taxonomy. Some similar relationships of taxa and trace elements between Yangtze floodplain lakes and Yunnan plateau lakes indicated that certain families of Submerged Macrophytes accumulate specific elements. Differences in relationships of taxa and trace elements between Yangtze floodplain lakes and Yunnan plateau lakes indicated that trace element composition of Submerged Macrophytes could be affected both by taxonomy and the ambient environment.
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growth rate protein rna ratio and stoichiometric homeostasis of Submerged Macrophytes under eutrophication stress
Knowledge and Management of Aquatic Ecosystems, 2016Co-Authors: Wei Xing, Han Liu, Qingshan Shi, Guihua LiuAbstract:Growth rate hypothesis (GRH) and stoichiometric homeostasis of photoautotrophs have always been questioned. However, little is known about GRH and stoichiometric homeostasis of aquatic plants, especially Submerged Macrophytes. Therefore, we aim to test the GRH and explore stoichiometric homeostasis of four freshwater Submerged Macrophytes under eutrophication stress. At the single species level and the multi-species level, N:P ratios of Potamogeton maackianus , Myriophyllum spicatum , Vallisneria natans and Ceratophyllum demersum had no consistent trends with growth rates. However, protein:RNA ratios of P. maackianus , M. spicatum and V. natans all correlated negatively with growth rates, demonstrating GRH can apply to freshwater Submerged Macrophytes, even though they are threatening by eutrophication stress. Protein:RNA ratios positively correlated with N:P ratios in culture media and tissues in Submerged Macrophytes except in P. maackianus (30d), suggesting effects of varying N:P ratios in culture media on protein:RNA ratios are basically in concert with tissue N:P ratios under short-time eutrophication stress. Stoichiometric homeostasis coefficients (H N:P ) indicated Submerged Macrophytes have weak homeostasis. Stoichiometric homeostasis of V . natans was stronger than those of P. maackianus , M. spicatum and C. demersum . The differences in GRH and homeostasis of the four Submerged Macrophytes may be due to species traits.
Erik Jeppesen - One of the best experts on this subject based on the ideXlab platform.
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response of community composition and biomass of Submerged Macrophytes to variation in underwater light wind and trophic status in a large eutrophic shallow lake
Journal of Environmental Sciences-china, 2021Co-Authors: Baili Dong, Erik Jeppesen, Yongqiang Zhou, Kun Shi, Boqiang QinAbstract:Abstract Light climate is of key importance for the growth, community composition of Submerged Macrophytes in lakes and, they, in turn, are affected by lake depth and the degree of eutrophication. To test the relationships between Submerged macrophyte presence and the ratio of Secchi disk depth (SDD) to water depth, i.e. SDD/depth, nutrients and wind, we conducted an extensive sampling campaign in a macrophyte-dominated area of the eastern region (n = 36) in 2016 in Lake Taihu, China, and combined the data gathered with results from extensive physico-chemical monitoring data from the entire lake. We confirmed that SDD/Depth is the primary factor controlling the community composition of Macrophytes and showed that plant abundance increased with increasing SDD/Depth ratio (p 0.4 ensured growth of Submerged Macrophytes. Total phosphorus and total nitrogen also influenced the growth and community composition of Macrophytes (p 0.05). The key to restore the macrophyte beds in the lake is to reduce the nutrient loading. A decrease of the water level may contribute as well in the shallow bays but will not bring plants back in the main part of the lake. As the tolerance of shade and nutrients varied among the species studied, this should be taken into account in the restoration of lakes by addition of plants.
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responses of Submerged Macrophytes and periphyton to warming under two nitrogen scenarios a microcosm study
Hydrobiologia, 2021Co-Authors: Yang Liu, Erik Jeppesen, Celina Aznarez, Eti E Levi, Juan Pablo Pacheco, Yu CaoAbstract:Warming and higher nitrogen loading induced by increasing precipitation are expected scenarios in north temperate regions as consequence of global climate change, with potential effects on the functional traits of Submerged Macrophytes and periphyton. Using an experimental heating facility we investigated the responses of three-week growth of two Submerged Macrophytes (Potamogeton crispus Linn. and Elodea canadensis Michx.), and periphyton on these plants and their artificial mimics. Analysis was based on IPCC climate scenarios A2 (ca. + 3°C) and A2 + 50% (called A3 in our study) relative to ambient conditions, across warming in spring and early summer (summer showed higher nitrogen loading). Some functional traits of plants showed species-specific responses to warming: A3 promoted the growth of E. canadensis in both seasons, while for P. crispus warming reduced the leaf number in spring but enhanced the turion production in early summer. Periphyton biomass was lower in A3 in early summer, but not in spring. Our results further show that the growth of E. canadensis and the asexual reproduction of P. crispus might increase in a warmer future. Moreover, we found a complex response of periphyton to the temperature increase and substrate type, varying with season and nutrient state.
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species specific responses of Submerged Macrophytes to the presence of a small omnivorous bitterling acheilognathus macropterus
Science of The Total Environment, 2021Co-Authors: Manli Xia, Baohua Guan, Zhengwen Liu, Erik JeppesenAbstract:Recovery of Submerged Macrophytes has been considered a key factor in the restoration of shallow eutrophic lakes. However, in some subtropical restored lakes, small omnivorous fish dominate the fish assemblages and feed in part on Submerged Macrophytes. Knowledge of the effects of small omnivores on the growth of Submerged Macrophytes is scarce and their responses are potentially species-specific, i.e. the growth of some species may be hampered by fish grazing while growth of others may be promoted by the nutrients becoming available by fish excretion. We conducted mesocosm experiments to examine the effects of the small omnivorous bitterling Acheilognathus macropterus, a common species in restored subtropical lakes in China, on nutrient concentrations and the growth of four species of Submerged Macrophytes (Hydrilla verticillata, Vallisneria denseserrulata, Ceratophyllum demersum and Myriophyllum spicatum). We found that the bitterling significantly increased nutrient concentrations via excretion and thereby enhanced the net growth of the less grazed nuisance macrophyte M. spicatum. In contrast, the net growth of C. demersum was reduced by the bitterling, most likely due to grazing as indicated by gut content analyses. Dominance by bitterling may, therefore, pose a threat to the long-term success of lake restoration by provoking a shift in the Submerged macrophyte community towards nuisance species through selective grazing. Nutrient excretion may potentially also stimulate the growth of phytoplankton and periphyton, hampering the growth of Submerged macrophyte.
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bio cord plays a similar role as Submerged Macrophytes in harboring bacterial assemblages in an eco ditch
Environmental Science and Pollution Research, 2018Co-Authors: Lei Zhou, Erik Jeppesen, Guang Gao, Chengrong Bai, Jian Cai, Keqiang Shao, Xiangming TangAbstract:Artificial carriers are widely used to enhance the formation of biofilm and improve pollutants' removal efficiency in agricultural wastewater treatment ditches (eco-ditches), yet comprehensive insight into their bacterial community is scarce. In this study, bacterial diversities in four different habitats-the water column, surface sediments, Submerged Macrophytes (Myriophyllum verticillatum L.), and the artificial carriers (bio-cord)-were compared in a Chinese eco-ditch. Comparable richness and evenness of bacterial communities were observed on M. verticillatum and bio-cord, both being higher than for free-living bacteria in the water column but lower than for bacteria in the surface sediment. The highest similarity of bacterial community composition and structure also occurred between M. verticillatum and the bio-cord, dominated by α- and γ-proteobacteria, Verrucomicrobia, and Bacteroidetes. Firmicutes and Planctomycetes, respectively, were the exclusive abundant phyla in M. verticillatum and the bio-cord, probably indicating the unique interaction between M. verticillatum and their epiphytic bacteria. Some abundant genera, such as Roseomonas, Pseudomonas, and Rhodopirellula, which were exclusively observed in M. verticillatum or the bio-cord, have been reported to have the same capacity to remove nitrogen and organic matter in wastewater treatment systems. In conclusion, in the studied eco-ditch, the bio-cord was found to play a similar role as Submerged Macrophytes in harboring bacterial assemblages, and we therefore propose that bio-cord may be a good alternative or supplement to enhance wastewater treatment in agricultural ditches.
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synergistic negative effects of small sized benthivorous fish and nitrogen loading on the growth of Submerged Macrophytes relevance for shallow lake restoration
Science of The Total Environment, 2018Co-Authors: Hui Jin, Erik Jeppesen, Robert W NairnAbstract:Rapid recruitment of small fish after biomanipulation in warm lakes may delay the reestablishment of Submerged Macrophytes, not least at high nutrient concentrations. Success has recently been obtained in controlling phosphorus (P) loading to many lakes, but nitrogen (N) inputs often remain high. To determine the interactive effects of N loading and the abundance of small-sized fish on the growth of the Submerged macrophyte Vallisneria natans, we conducted an outdoor mesocosm experiment with a factorial design on the north shore of Lake Taihu, China. The experiment involved two densities of small crucian carp - low (10gm-2) and high (40gm-2) - crossed with two levels of N loading - present-day external nutrient loading (P: 5μgL-1day-1, N: 130μgL-1day-1) and P: 5μgL-1day-1 with a three times higher N loading (N: 390μgL-1day-1). The results showed that nitrogen-fish interactions significantly hindered the growth of V. natans, particularly at the high N loading. At low N loading, high densities of fish decreased the relative growth rate, mean leaf length, leaf mass and root mass of V. natans by 16%, 5%, 8%, and 23%, respectively, compared with these measures at low fish densities. The effect of fish was even stronger when N loading was high, with decreases of 232%, 32%, 57%, and 47% for the respective plant growth measures. The stronger effect at high N loading was attributed to higher turbidity due to enhanced phytoplankton biomass and to increased consumption or damage of plants by the fish in response to the more nutrient-enriched plant tissue. Our results indicate that high abundance of small crucian carp in warm lakes may reduce the resilience of Submerged Macrophytes to external N loading, thereby lowering the chances of successful restoration by biomanipulation.
Jun Chen - One of the best experts on this subject based on the ideXlab platform.
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stoichiometric and physiological mechanisms that link hub traits of Submerged Macrophytes with ecosystem structure and functioning
Water Research, 2021Co-Authors: Qingyang Rao, Hong Shen, Jun Chen, Linwei Ruan, Xuwei Deng, Lantian Wang, Xiao Rao, Jiarui Liu, Wulai Xia, Ping XieAbstract:Eutrophication strongly influences plant stoichiometric characteristics and physiological status by altering nutrient and light availability in the water column. However, the mechanisms linking plant functional traits with ecosystem structure and functioning to clarify the decline of Submerged Macrophytes have not been fully elucidated to date. Therefore, based on a field investigation of 26 macrophytic shallow lakes on the Yangtze Plain, we first constructed a plant trait network at the whole-plant level to determine the hub traits of Submerged Macrophytes that play central regulatory roles in plant phenotype. Our results suggested that organ (leaf, stem, and root) phosphorus (P), starch, and total nonstructural carbohydrate (TNC) contents were hub traits. Organ starch and TNC were consistent with those in the experiment-based network obtained from a three-month manipulation experiment. Next, the mechanisms underlying the relationships between the hub traits and vital aspects of ecological performance were carefully investigated using field investigation data. Specifically, stoichiometric homeostasis of P (HP), starch, and TNC were positively associated with dominance and biomass at the species level, and community biomass at the community level. Additionally, structural equation modeling clarified not only a hypothesized pathway from eutrophication to water clarity and community TNC, but also combined effects of community TNC and HP on community biomass. That is, ecosystems dominated by more homeostatic communities tended to have more carbon (C)-rich compounds in relatively oligotrophic conditions, which promoted the primary production of Macrophytes. Eutrophication was determined to affect community structure by inhibiting the predominance of more homeostatic species and the production of carbohydrates. Finally, reduced community biomass and increased nutrient contents and nutrient:C ratios in plants induced by eutrophication implied a decrease in the C sink in biomass and may potentially lead to an enhancement of litter decomposition rates and nutrient cycling rates. By adjusting plant responses to eutrophication, stoichiometric and physiological mechanisms linking plant traits with ecosystem structure have important implications for understanding ecosystem processes, and these results may contribute to practical management to achieve the restoration of Submerged Macrophytes and ecosystem services.
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proliferation of filamentous green algae along with Submerged Macrophytes planting and the role of microbe
Ecological Engineering, 2019Co-Authors: Weizhen Zhang, Hong Shen, Li Wang, Liang Chen, Jun ChenAbstract:Abstract Excessive proliferation of filamentous green algae (FGA) is a problem that commonly occurs following the remediation of Submerged Macrophytes during lake restoration. Cultivation of Submerged Macrophytes changes the physical and chemical environment and micro-habitats for survival and growth of FGA. However, effects of Submerged Macrophytes on FGA and the mechanisms are largely unknown. In this study, artificial grass (controls) and two Submerged Macrophytes (Potamogeton maackianus and Vallisneria natans) with different leaf complexity were cultivated at densities of 3, 6, and 9 in aquaria for a month. The proliferation of FGA, photosynthetic performance of Macrophytes, and possible roles of bacteria in the interaction of Macrophytes and FGA were studied. Compared with controls, planting of P. maackianus promoted the proliferation of epiphytic FGA, and the effects were density-dependent. Also, density-dependent decrease of photosynthetic performance of P. maackianus were observed. However, in the groups of V. natans, proliferation of epiphytic FGA showed density-dependent inhibition, but photosynthesis of V. natans showed density-dependent promotion. Furthermore, photosynthesis of Macrophytes was negatively correlated with growth of epiphytic FGA (Chl a contents). Abundances of epiphytic bacteria taxa such as members of orders Rhodobacterales, Nitrosomonadales and Gemmatimonadales on P. maackianus were greater than those on V. natans. The abundances of these bacteria were positively related to Chl a contents of epiphytic algae (FGA). Thus, proliferation of FGA might be partly attributed to accumulation of certain bacteria taxa on the Submerged Macrophytes planted during lake restoration. To avoid excess proliferation of FGA, careful selection of Submerged aquatic Macrophytes is needed.
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Physiological differences between free-floating and periphytic filamentous algae, and specific Submerged Macrophytes induce proliferation of filamentous algae: A novel implication for lake restoration.
Chemosphere, 2019Co-Authors: Weizhen Zhang, Hong Shen, Jia Zhang, Ping Xie, Jun ChenAbstract:Abstract Restoration of Submerged Macrophytes is widely applied to counteract eutrophication in shallow lakes. However, proliferation and accumulation of filamentous algae (possessing free-floating and periphytic life forms) hamper growth of Submerged Macrophytes. Here, we explored factors triggering the excessive proliferation of filamentous algae during lake restoration using field investigations and laboratory experiments. Results showed that, compared with free-floating Oscillatoria sp. (FO), periphytic Oscillatoria sp. (PO) showed faster growth rate, greater photosynthetic capacities and higher phosphorus (P) affinity. Therefore, PO was physiologically competitively superior to FO under low P concentration and improved light conditions. And proliferation of filamentous algae was mainly manifested in periphytic life form. Besides, field results showed that density of filamentous algae in water column might be related to substrate types. Some macrophyte (Ceratophyllum oryzetorum and Potamogeton crispus) might provide proper substrates for proliferation of filamentous algae. Further physiological experiments found that Oscillatoria showed specific eco-physiological responses to different macrophyte species. Hydrilla verticillata and C. oryzetorum promoted growth and photosynthetic activity of Oscillatoria, while Potamogeton malaianus inhibited growth and P uptake of PO. Myriophyllum spicatum exhibited no impact on growth of Oscillatoria. Our results revealed the intrinsic (physiological differences between free-floating and periphytic life forms of filamentous algae) and extrinsic (different Macrophytes) factors affect the proliferation of filamentous algae, which are important for guidance on planting of Submerged Macrophytes during lake restoration.
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effects of taxonomy sediment and water column on c n p stoichiometry of Submerged Macrophytes in yangtze floodplain shallow lakes china
Environmental Science and Pollution Research, 2016Co-Authors: Ping Xie, Jun Chen, Te Cao, Wulai XiaAbstract:Carbon (C), nitrogen (N) and phosphorus (P) are the three most important essential elements limiting growth of primary producers. Submerged Macrophytes generally absorb nutrients from sediments by root uptake. However, the C:N:P stoichiometric signatures of plant tissue are affected by many additional factors such as taxonomy, nutrient availability, and light availability. We first revealed the relative importance of taxonomy, sediment, and water column on plant C:N:P stoichiometry using variance partitioning based on partial redundancy analyses. Results showed that taxonomy was the most important factor in determining C:N:P stoichiometry, then the water column and finally the sediment. In this study, a significant positive relationship was found between community C concentration and macrophyte community biomass, indicating that the local low C availability in Macrophytes probably was the main reason why Submerged Macrophytes declined in Yangtze floodplain shallow lakes. Based on our study, it is suggested that Submerged Macrophytes in Yangtze floodplain shallow lakes are primarily limited by low light levels rather than nutrient availability.
Yi Zhang - One of the best experts on this subject based on the ideXlab platform.
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plant growth promoting rhizobacteria isolation from rhizosphere of Submerged Macrophytes and their growth promoting effect on vallisneria natans under high sediment organic matter load
Microbial Biotechnology, 2021Co-Authors: Chuan Wang, Yi Zhang, Wenhao Yan, Huihui Wang, Qiaohong ZhouAbstract:Sediment organic matter is a key stressor for Submerged macrophyte growth, which negatively impacts the ecological restoration of lakes. Plant growth-promoting rhizobacteria (PGPR) were screened from the rhizosphere of Submerged Macrophytes and used due to their promoting effect on Vallisneria natans under a high sediment organic matter load. Root exudates were used as the sole carbon source to obtain the root affinity strains. Eight isolates were selected from the 61 isolated strains, based on the P solubilization, IAA production, cytokinins production and ACC deaminase activity. The analysis of the 16S rDNA indicated that one strain was Staphylococcus sp., while the other seven bacterial strains were Bacillus sp. They were all listed in low-risk groups for safety use in agricultural practices. The plant height significantly increased after inoculation with PGPR strains, with the highest rate of increase reaching 96%. This study provides an innovative technique for recovering Submerged Macrophytes under sediment organic matter stress.
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spatial and seasonal variation of water parameters sediment properties and Submerged Macrophytes after ecological restoration in a long term 6 year study in hangzhou west lake in china Submerged macrophyte distribution influenced by environmental var
Water Research, 2020Co-Authors: Lingwei Kong, Chuan Wang, Yi Zhang, Guoliang Bai, Pan Yan, Wenhao Yan, Lai Wang, Z Q LiuAbstract:Abstract Submerged macrophyte restoration is the key stage in the reestablishment of an aquatic ecosystem. Previous studies have paid considerable attention to the effect of multiple environmental factors on Submerged Macrophytes. Meanwhile, few studies have been conducted regarding the spatial and seasonal characteristics of water and sediment properties and their long-term relationship with Submerged Macrophytes after the implementation of the Submerged Macrophytes restoration project. On a monthly basis, we monitored the spatial and seasonal variation in water parameters, sediment properties, and the Submerged macrophyte characteristics of West Lake in Hangzhou from August 2013 to July 2019. From these measurements, we characterized the relationship between environmental factors and Submerged Macrophytes. Water nutrient concentrations continuously decreased with time, and the accumulation of sediment nutrients was accelerated as the Submerged macrophyte communities developed on a long-term scale. The results indicated that the difference in water parameters was due to seasonal changes and land-use types in the watershed. The differences in the sediment properties were mainly attributed to seasonal changes and changes in the flow field. Redundancy analysis showed that the influence of water nutrients on the Submerged macrophyte distribution was greater than that of sediment nutrients. The result also suggested that the developed root system, high stoichiometric homeostasis coefficients of P, and compensation ability of substantial leaf tissue may lead to a large distribution of Vallisneria natans in West Lake in Hangzhou. The correlation of water parameters and sediment properties with Submerged Macrophytes for a long time was very important as the restoration was achieved. To ensure the stability of the aquatic ecosystem after performing the Submerged macrophyte restoration, a greater emphasis must be placed on reestablishing the entire ecosystem, including the restoration of aquatic animals and fish stocks. We expect these findings to serve as a reference for researchers and government agencies in the field of aquatic ecosystem restoration.
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the promotion effects of silicate mineral maifanite on the growth of Submerged Macrophytes hydrilla verticillata
Environmental Pollution, 2020Co-Authors: Lingwei Kong, Zhenbin Wu, Feng He, Chuan Wang, Yi ZhangAbstract:Abstract The effects of maifanite on the physiological and phytochemical process of Submerged Macrophytes Hydrilla verticillate (H.verticillata) were investigated for the first time in the study. The growth index: plant biomass, root length, plant height and leaf spacing, and physiological and phytochemical indexes: chlorophyll, soluble protein, malondialdehyde (MDA), peroxidase (POD), superoxide dismutase (SOD) content and vitality of the roots of H.verticillata were tested. The results found that maifanite can significantly promote the growth of H.verticillata. The modified maifanite were more conducive to plant growth compared with the raw maifanite, and the MM1 group had the best growth promoting effect. The physiological and phytochemical indexes showed that maifanite can delay the aging process of H.verticillata (P
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synergistic control of internal phosphorus loading from eutrophic lake sediment using mmf coupled with Submerged Macrophytes
Science of The Total Environment, 2020Co-Authors: Zisen Liu, Lingwei Kong, Yi Zhang, Pan Yan, Ji Luo, Junjun Chang, Biyun LiuAbstract:Abstract Sediment phosphorus (P) is the main source of endogenous P for lake eutrophication. An in-situ combined technology for determination the removal effect of sediment P in all fractions was first developed using the novel modified maifanite (MMF) and Submerged Macrophytes in this study. MMF was synthesized using an acidification process (2.5 mol/L H2SO4) and then a calcination (400 °C) method. The morphology and structure of MMF were characterized by XRD, SEM, XPS, and BET. We tested the removal effects of sediment P by MMF and Submerged Macrophytes in combination and separately. The results demonstrated that the synergistic removal capacity of sediment P using MMF coupled with Submerged Macrophytes was higher than the sum of them applied separately. MMF could promote the Submerged Macrophytes growth and enhance the adsorption of extra P on MMF through root oxygenation and nutrient allocation. The microcosm experiment results showed that sediment from fMMF+V. spiralis exhibited the most microbial diversity and abundance among the sediment. The combination of MMF and Submerged Macrophytes increased the Firmicutes abundance and decreased the Bacteroidetes. These results indicated that adsorption-biological technology can be regarded as a novel and competitive technology to the endogenous pollution control in eutrophic shallow lakes.
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Synergistic control of internal phosphorus loading from eutrophic lake sediment using MMF coupled with Submerged Macrophytes
'Elsevier BV', 2020Co-Authors: Liu Zisen, Yi Zhang, Xu Xi-dong, Ji Luo, Yan Pan, Kong Lingwei, Chang Junjun, Liu Biyun, He Feng, Wu ZhenbinAbstract:Sediment phosphorus (P) is the main source of endogenous P for lake eutrophication. An in-situ combined technology for determination the removal effect of sediment P in all fractions was first developed using the novel modified maifanite (MMF) and Submerged Macrophytes in this study. MMF was synthesized using an acidification process (2.5 mol/L H2SO4) and then a calcination (400 degrees C) method. The morphology and structure of MMF were characterized by XRD, SEM, XPS, and BET. We tested the removal effects of sediment P by MMF and Submerged Macrophytes in combination and separately. The results demonstrated that the synergistic removal capacity of sediment P using MMF coupled with Submerged Macrophytes was higher than the sum of them applied separately. MMF could promote the Submerged Macrophytes growth and enhance the adsorption of extra P on MMF through root oxygenation and nutrient allocation. The microcosm experiment results showed that sediment from fMMF+V. spiralis exhibited the most microbial diversity and abundance among the sediment. The combination of MMF and Submerged Macrophytes increased the Firmicutes abundance and decreased the Bacteroidetes. These results indicated that adsorption-biological technology can be regarded as a novel and competitive technology to the endogenous pollution control in eutrophic shallow lakes. (C) 2020 Elsevier B.V. All rights reserved
