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Chen Yu,Ren Jiuchang,Cai Xiaoming,

环境科学学报 , 1998,
Abstract: Physiological and biochemical effects of cadmium on four species of submerged macrophytes were tested. The results showed that above certain concentration, Cd could induce the activity of nitrate reductase, and inhibit the activity of superoxide dismutase. Thus the antioxidant defense system of these species was injured. There was a positive correlation between dose and effect. Based on the results of this study the activity of superoxide dismutase of submerged macrophytes are expected to be used to monitor and evaluate aquatic ecosystem as a biomarker.
Influence of submerged macrophytes on phosphorus transference between sediment and overlying water in the growth period

Wang Li-Zhi,Wang Guo-Xiang,Yu Zhen-Fei,Zhou Bei-Bei,Chen Qiu-Min,Li Zhen-Guo,
Wang LZ
,Wang GX,Yu ZF,Zhou BB,Chen QM,Li ZG

环境科学 , 2012,
Abstract: In order to study the process of phosphorus transfer between sediment and overlying water, Hydrilla verticillata and Vallisneria natans were cultured in spring, Potamogeton crispus was cultured in winter. Changes of environmental factors and phosphorus concentrations in water and sediment were investigated. The results indicated that: submerged macrophytes could reduce all phosphorus fractions in the overlying water. Phosphorus concentrations in overlying water maintained in a relative low level in the growth period of submerged macrophytes. The concentrations of total phosphorus (TP) in overlying water of H.verticillata, V. natans and P. crispus were 0.03-0.05,0.04-0.12,0.02-0.11 mg·L-1, respectively. All phosphorus fractions in sediment were reduced. The maximum value between submerged macrophyte and control of H.verticillata, V. natans and P. crispus were 35.34, 60.67 and 25.92 mg·kg-1, respectively.Dissolved oxygen (DO), redox potential (Eh) and pH in overlying water increased (DO 10.0-14.0 mg·L-1, Eh 185-240 mV, pH 8.0-11.0) in the submerged macrophytes groups. Submerged macrophytes increased Eh(-140--23 mV) and maintained pH(7.2-8.0) in neutral range. The results indicated that submerged macrophytes affected phosphorus transferring between sediment and overlying water through increasing DO,Eh and pH in overlying water, and Eh in sediment.
Effects of rehabilitation of submerged macrophytes on nutrient level of a eutrophic lake

WU Zhenbin,QIU Dongru,HE Feng,FU Guiping,CHENG Shuiping,MA Jianmin,

应用生态学报 , 2003,
Abstract: The effects of rehabilitation of submerged aquatic vegetation on nutrient level of eutrophic waters were investigated by using large-scale enclosure system installed in a hyper-eutrophicated lake, Lake Donghu of Wuhan. The concentrations of total nitrogen (TN) and total phosphorus (TP) of the enclosures with artificially recovered submerged macrophytes were significantly lower than those of the macrophyte-free control enclosure and the lake water, and the TP of macrophyte enclosure was found to be around 0.1 mg.L-1 and relatively stable. The concentration of ammonia and nitrite of the macrophyte enclosures were lower than those of the control and the lake water. However, the nitrate concentrations did not differ among the various water bodies. It was demonstrated that re-establishment of submerged macrophytes could efficiently reduce the nutrient level and thus control the overgrowth of the undesirable algae and improve water quality in the eutrophic lakes.
Invasive Crayfish Threaten the Development of Submerged Macrophytes in Lake Restoration  [PDF]
Jessica E. M. van der Wal, Martijn Dorenbosch, Anne K. Immers, Constanza Vidal Forteza, Jeroen J. M. Geurts, Edwin T. H. M. Peeters, Bram Koese, Elisabeth S. Bakker
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0078579
Abstract: Submerged macrophytes enhance water transparency and aquatic biodiversity in shallow water ecosystems. Therefore, the return of submerged macrophytes is the target of many lake restoration projects. However, at present, north-western European aquatic ecosystems are increasingly invaded by omnivorous exotic crayfish. We hypothesize that invasive crayfish pose a novel constraint on the regeneration of submerged macrophytes in restored lakes and may jeopardize restoration efforts. We experimentally investigated whether the invasive crayfish (Procambarus clarkii Girard) affects submerged macrophyte development in a Dutch peat lake where these crayfish are expanding rapidly. Seemingly favourable abiotic conditions for macrophyte growth existed in two 0.5 ha lake enclosures, which provided shelter and reduced turbidity, and in one lake enclosure iron was added to reduce internal nutrient loading, but macrophytes did not emerge. We transplanted three submerged macrophyte species in a full factorial exclosure experiment, where we separated the effect of crayfish from large vertebrates using different mesh sizes combined with a caging treatment stocked with crayfish only. The three transplanted macrophytes grew rapidly when protected from grazing in both lake enclosures, demonstrating that abiotic conditions for growth were suitable. Crayfish strongly reduced biomass and survival of all three macrophyte species while waterfowl and fish had no additive effects. Gut contents showed that crayfish were mostly carnivorous, but also consumed macrophytes. We show that P. clarkii strongly inhibit macrophyte development once favourable abiotic conditions for macrophyte growth are restored. Therefore, expansion of invasive crayfish poses a novel threat to the restoration of shallow water bodies in north-western Europe. Prevention of introduction and spread of crayfish is urgent, as management of invasive crayfish populations is very difficult.
Limnological variables and nutritional content of submerged aquatic macrophytes in a tropical lagoon
Esteves, Bruno dos Santos;Suzuki, Marina Satika;
Acta Limnologica Brasiliensia , 2010, DOI: 10.4322/actalb.02202008
Abstract: aim: the aim of this study was to evaluate elemental composition (c, n and p) and carbohydrate and lipids content of aquatic macrophytes egeria densa, ceratophyllum demersum and najas marina found in a lagoon of norte fluminense and relate these data to limnological parameters measured in the same period; methods: the samples were obtained from 10 sites throughout the lagoon in july/2001 (dry season) and january/2002 (rainy season) with determinations limnological parameters and quantification of nutrient content and biochemical composition of the aquatic macrophytes; results: high values of electrical conductivity and alkalinity explain the spatial distribution of the studied macrophytes; and the ph values (<9.0), o2 super-saturation and co2 sub-saturation suggest a high primary production of both phytoplankton and submersed aquatic macrophytes. for nutrients assessed on aquatic macrophytes, significant seasonal variations were observed in total phosphorus content (p < 0.05), total nitrogen and total carbon, however, without a clear pattern between seasons and macrophytes there was a tendency to higher concentrations of p in the tissues of macrophytes in the rainy season, as well as carbohydrates and lipids, suggesting that this period presents better conditions to ceratophyllum demersum and egeria densa development in the campelo lagoon; conclusions: there was no clear association between the nutrient content and reserves found in macrophytes with limnological and environmental parameters.
Bellamya sp. and its interaction with submerged macrophytes in Lake Taihu
太湖环棱螺(Bellamya sp.)及其与沉水植物的相互作用

BAI Xiu-Ling,GU Xiao-Hong,HE Jun,

生态学报 , 2009,
Abstract: We measured nutrient release by the freshwater snail Bellamya sp. under different environmental conditions. In addition, we examined the effects of Bellamya sp. on water transparency, nutrient concentrations, growth of naturally-occurring phytoplankton, and its interactions with Hydrilla verticillata Royle, Elodea nuttalli ST John of Lake Taihu, China. Results showed that the rate of nutrient release by snails was affected by water temperature and the food they stored. The release rates increased with temperature increases. Nutrient release rates by snails were higher after they fed than when they were starved at the constant temperature. Bellamya sp. increased the transparency of water column on a short term, while the release of nutrients led to measurable increases in concentrations of nitrogen and phosphorus. The nutrients released by Bellamya sp., combined with adequate temperature and illumination, allowed phytoplankton growth to exceed remove by snail feeding. At the same time,nutrient release by Bellamya sp. promoted the growth of Hydrilla verticillata Royle and of Elodea nuttalli ST John. A survey of Bellamya sp. in Lake Taihu showed that snail biomass in the submerged macrophyte-dominated areas was higher than that in areas dominated by phytoplankton, and the submerged macrophytes played an important role in the distribution of snails. Collectively, the combination of biomanipulation of snails and restoration of submerged macrophytes shows promise in countering eutrophication, and improvement of water quality.
Absorption and Purification of Heavy Metals by Submerged Macrophytes and Its Mechanism

Jianmin Ma,Ping Jin,Zhenbin Wu,

植物学报 , 2007,
Abstract: The author reviewed the absorption and purification of heavy metals by submerged macrophytes and the mechanism of harm. Four aspects were summarized and analyzed: (1) absorption and purification of heavy metals by submerged macrophytes;(2) resistance of submerged macrophytes to the stress of heavy metals and the mechanism; (3) monitoring the polluted water by heavy metals with submerged macrophytes; and (4) the stress of heavy metal contamination and its mechanism in submerged macrophytes.
Simple relationships to predict attributes of fish assemblages in patches of submerged macrophytes
Pelicice, Fernando Mayer;Thomaz, Sidinei Magela;Agostinho, Angelo Antonio;
Neotropical Ichthyology , 2008, DOI: 10.1590/S1679-62252008000400001
Abstract: submerged macrophytes play an important role in structuring habitats and, therefore, in determining patterns of aquatic biodiversity. because these plants are widespread in shallow areas of many neotropical reservoirs, the present work investigated if variables related to habitat structure, measured in patches of submerged macrophytes (egeria densa and e. najas), can be used to predict fish assemblage attributes (fish density and species richness). based on patch characteristics at fine spatial extents (macrophyte patches within reservoir arms), we considered plant biomass, volume and proportional volume (i.e. percentage of macrophyte volume in the water column) as potential predictors. fish and macrophytes were sampled with a 1-m2 throw trap in littoral habitats of rosana reservoir, paranapanema river, and simple correlation analyses were performed. fish richness and abundance were highly correlated with all variables (r = 0.53 to 0.90), a relationship consistently observed in all sites. when compared to biomass, plant volume and proportional volume did not yield stronger correlations. we observed stronger correlations when e. densa and e. najas patches were analyzed separately (mono-specificity), probably because particular effects of each macrophyte on habitat structuring were removed (e.g. unnoticed morphological differences or unknown effects on habitat quality). the high r values observed in all pairwise relationships are uncommon in ecological studies, highlighting the predictive potential of variables related to habitat structure. these results suggest that, at small spatial extents, macrophyte biomass may represent an interesting predictor of fish density and richness in reservoirs with extensive colonization of submerged plants.
Effect of macrophytes on nitrogen and phosphorus in Luoma Lake

Wan Lei,Xu Delan,Gao Mingxi,Han Baoping,Song Xinheng,Dong Xiao,

环境工程学报 , 2012,
Abstract: The nitrogen and phosphorus contents in the water and sediment with and without macrophytes in Luoma Lake were analyzed.The results indicate that the concentrations of TN and TP in water without macrophytes are higher than that with macrophytes.TN in the surface layer of sediment with macrophytes changes significantly with time,while without macrophytes is opposite.The change of TP with and without macrophytes with time does not have significant difference.TN is basically higher with macrophytes than that without macrophytes,while TP is lower.Alkaline phosphatase activity in the surface layer of sediment changes between 58.41~315.07 mg/(kg·h),and is lower with macrophytes than that without macrophytes.Plant macrophytes in lakes can indeed reduce pollution,and achieve the purpose of purifying water quality.
Physiological effects of dissolved inorganic carbon on common submerged Macrophytes

水生生物学报 , 2009,
Abstract: Dissolved inorganic carbon (DIC) is a fundamental resource for photosynthesis of plants. The forms of DIC in water include CO2, HCO3- and CO32-. Recent studies have shown that DIC potentially limited the growth and photosynthesis of several submerged macrophytes. In order to elucidate the impacts of the states of DIC in hyper-eutrophic lakes caused by water bloom on the growth of submerged macrophytes, the growth, chlorophyll and photosynthetic and respiration rates of eight species of submerged macrophytes, including Ceratophyllum demersum, Myriophyllum spicatum, Potamogeton pectinatus, Potamogeton lucens, Potamogeton maackianus, Elodea nattalii, Potamogeton crispus and Hydrilla verticillata, were investigated under different DIC conditions. The results indicated that HCO3- could be used as a carbon source by all the submerged macrophytes tested. Improvement of growth and photosynthetic rates was found on C. demersum, P. crispus and E. nattalii under exogenous HCO3- below 1.5mmol/L, and also on M. spicatum, P. lucens, H. verticillata, P. maackianus and P. pectinatus under exogenous HCO3- below 2.5 mmol/L, however, when CO32- acted as the dominate carbon source, different effects were found on the eight kinds of submerged macrophytes. Growth and photosynthetic rates of P. maackianus, P. pectinatus and H. verticillata were not inhibited, and showed improvement under certain CO32- concentrations, which indicated that the three species of macrophytes could adapt to a wide range of HCO3-]/ CO32-] ratio and pH value. In contrast, the growth of C. demersum and E. nattalii were inhibited, and M. spicatum, P. crispus and P. lucens were died under the conditions of CO32- as dominate carbon source, indicating HCO3-]/ CO32-] ratio and pH values were the important limiting factors of growth for the above 5 species of submerged macrophytes.
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