scholarly journals Impact of microplastics on the foraging, photosynthesis and digestive systems of submerged carnivorous macrophytes under low and high nutrient concentrations

2022 ◽  
Vol 292 ◽  
pp. 118220
Author(s):  
Hongwei Yu ◽  
Weixiao Qi ◽  
Xiaofeng Cao ◽  
Yajun Wang ◽  
Yang Li ◽  
...  
Keyword(s):  
Nutrient Concentrations ◽  
High Nutrient

Nutrient Input and Trophic Status of the “Neue Donau”, a High-Water Control System along the River Danube in Vienna, Austria

1990 ◽  
Vol 22 (5) ◽  
pp. 137-144 ◽  
Author(s):  
M. T. Dokulil ◽  
G. A. Janauer
Keyword(s):  
Water Quality ◽  
Control System ◽  
Trophic Status ◽  
High Water ◽  
Nutrient Concentrations ◽  
Nutrient Input ◽  
Water Control ◽  
Trophic Conditions ◽  
River Danube ◽  
High Nutrient

The system “Neue Donau” functions as a control system for high waters of the river Danube and is an important recreational area for many people. Water quality and trophic status of the water body is thereforeof prime importance. The high nutrient concentrations of the river Danube (P-tot 238±41µg/l, N-tot 2.53±0.78 mg/l) reach the system via groundwater seepage. Present conditions in the basin of Neue Donau are,as a result of this nutrient in-flux,eutrophic to hypertrophic. Average values during the summer period have declined from 366 µg/l total phosphorus to 78 µg/l, and from 86 µg/l chlorophyll-a tol7µg/l between the years 1985 and 1988. However, a dam which is planned in the river at Vienna will permanently raise the water level of the river thus increasing the the groundwater flow in the direction to the Neue Donau and therefore the nutrient input which will enhance trophic conditions in the impoundment. Since macrophytes play an important role in one part of the system macrophyte management together with measures along the river are some of the suggested strategies to keep the system Neue Donau at acceptable trophic conditions and good water quality.

scholarly journals Fluctuated water depth with high nutrient concentrations promote the invasiveness of Wedelia trilobata in Wetland

2019 ◽  
Vol 10 (2) ◽  
pp. 832-842 ◽  
Author(s):  
Jianfan Sun ◽  
Qaiser Javed ◽  
Ahmad Azeem ◽  
Ikram Ullah ◽  
Muhammad Saifullah ◽  
...  
Keyword(s):  
Water Depth ◽  
Nutrient Concentrations ◽  
Wedelia Trilobata ◽  
High Nutrient

Major cyanobacterial bloom in the Barwon-Darling River, Australia, in 1991, and underlying limnological conditions

1996 ◽  
Vol 47 (4) ◽  
pp. 643 ◽  
Author(s):  
LC Bowling ◽  
PD Baker
Keyword(s):  
New South ◽  
Cyanobacterial Bloom ◽  
Low Flow ◽  
Nutrient Concentrations ◽  
Mouse Bioassay ◽  
Contributing Factors ◽  
South Wales ◽  
High Ammonia ◽  
High Nutrient ◽  
Very High

The occurrence of a severe cyanobacterial bloom is described. This bloom affected almost 1000 km of the Barwon-Darling River, New South Wales, Australia, in November and December 1991 and was dominated by Anabaena circinalis Rabenhorst. This cyanobacterium was present in concentrations of around half a million cells per millilitre at some localities during its peak in mid November. Moderate to very high toxicity was demonstrated by mouse bioassay at many localities during this time. The bloom was attributed to very low flow conditions and high nutrient concentrations, especially of total phosphorus. However, warm water temperatures, elevated pH, reduced turbidity, and improved water transparency would also have been contributing factors. Very high ammonia concentrations were also observed during the bloom. The bloom declined during December and was eventually flushed from the river by increased flows following heavy catchment rainfall between mid December and early January.

scholarly journals Fruit and vegetable intakes in relation to plasma nutrient concentrations in women in Shanghai, China

2011 ◽  
Vol 15 (1) ◽  
pp. 167-175 ◽  
Author(s):  
Cara L Frankenfeld ◽  
Johanna W Lampe ◽  
Jackilen Shannon ◽  
Dao L Gao ◽  
Wenjin Li ◽  
...  
Keyword(s):  
Vitamin C ◽  
Fruits And Vegetables ◽  
Disease Risk ◽  
Vegetable Consumption ◽  
Plasma Concentrations ◽  
Nutrient Concentrations ◽  
Fruit Intake ◽  
Fruit And Vegetable ◽  
Classification Schemes ◽  
High Nutrient

AbstractObjectiveTo evaluate the validity of fruit and vegetable intakes as it relates to plasma carotenoid and vitamin C concentrations in Chinese women, using three classification schemes.DesignIntakes were calculated using an interviewer-administered FFQ. Fruits and vegetables, botanical groups and high-nutrient groups were evaluated. These three classification schemes were compared with plasma carotenoid and vitamin C concentrations from blood samples collected within 1 week of questionnaire completion.SettingShanghai, China.SubjectsParticipants (n 2031) comprised women who had participated in a case–control study of diet and breast-related diseases nested within a randomized trial of breast self-examination among textile workers (n 266 064)ResultsFruit intake was significantly (P < 0·05) and positively associated with plasma concentrations of α-tocopherol, β-cryptoxanthin, lycopene, α-carotene, β-carotene, retinyl palmitate and vitamin C. Fruit intake was inversely associated with γ-tocopherol and lutein + zeaxanthin concentrations. Vegetable consumption was significantly and positively associated with γ-tocopherol and β-cryptoxanthin concentrations. Each botanical and high-nutrient group was also significantly associated with particular plasma nutrient concentrations. Fruit and vegetable intakes and most plasma nutrient concentrations were significantly associated with season of interview.ConclusionsThese results suggest that the manner in which fruits and vegetables are grouped leads to different plasma nutrient exposure information, which may be an important consideration when testing and generating hypotheses regarding disease risk in relation to diet. Interview season should be considered when evaluating the associations of reported intake and plasma nutrients with disease outcomes.

Effect of dietary nutrient concentration on the performance of hens beginning lay in early summer

1986 ◽  
Vol 26 (4) ◽  
pp. 405 ◽  
Author(s):  
AS Pell ◽  
RW Polkinghorne
Keyword(s):  
Egg Production ◽  
Nutrient Concentration ◽  
Early Summer ◽  
Nutrient Concentrations ◽  
Egg Mass ◽  
Meat Meal ◽  
High Nutrient ◽  
Dietary Nutrient ◽  
Metabolisable Energy ◽  
High Nutrient Concentration

Hens of 2 laying strains were fed ad libitum from 20 to 72 weeks of age on 3 diets of different nutrient concentration. The start of lay coincided with the onset of the hot summer. During summer, birds on the diet with high nutrient concentration (HNC, 19% protein, 12.6 MJ metabolisable energy (ME)/kg) had significantly higher intakes of ME (3% higher) and other nutrients than did those on the diets of medium (MNC, 18% protein, 11.7 MJ ME/kg) and low (LNC, 16% protein, 11.4 MJ ME/kg) nutrient concentration. Egg weight. egg mass and feed efficiency were greater on the HNC diet than on the MNC and LNC diets. Birds on the HNC diet produced more eggs (10% more) than those on the LNC diet. Over the cooler periods, feed intakes were inversely related to energy level, with no dietary effects on egg production. It is concluded that grain- and meat meal-based diets of low nutrient concentrations are unlikely to support maximum performance in early lay in hot conditions and that increased dietary nutrient concentrations can improve performance via increased nutrient intake.

scholarly journals Ant nests and soil nutrient availability: the negative impact of fire

2008 ◽  
Vol 24 (6) ◽  
pp. 639-646 ◽  
Author(s):  
Leandro Sousa-Souto ◽  
José H. Schoereder ◽  
Carlos Ernesto G. R. Schaefer ◽  
Washington L. Silva
Keyword(s):  
Negative Impact ◽  
Soil Nutrient ◽  
Exchange Capacity ◽  
Nutrient Concentrations ◽  
Negative Effects ◽  
Atta Laevigata ◽  
Ant Nests ◽  
Nutrient Patches ◽  
High Nutrient ◽  
Leaf Cutting

Abstract:High-nutrient patches are important for regulating the structure and physiognomy of dystrophic habitats. Leaf-cutting ants create these rich patches in many neotropical habitats. Burning, however, could diminish or even annul the effects of ant nests on soil properties. To test this hypothesis, we compared the nutrient concentrations at various depths in soil samples near three nests of the leaf-cutting ant Atta laevigata and three non-nest soils, located in 10-ha plots subjected to burning or with fire-protection within a Brazilian cerrado. Root density in ant-nest soil was greater than in non-nest soil in both unburned and burned plots. Besides, the concentration of Ca, Mg, K and P increased 2–50-fold in ant nests from the unburned area compared to non-nest soils. In contrast, nutrient concentrations and pH in burned ant nests were similar to or lower than non-nest soils, but the nests maintained higher values of organic matter and cation exchange capacity. The positive effect of leaf-cutting ant nests as high-nutrient patches may be strongly reduced in habitats with frequent burning. In this case, the negative effects of leaf-cutter herbivory on a plant community could surpass the benefits of local nutrient enrichment by their nests.Resumo: Sauveiros modificam as propriedades físicas e químicas do solo, alterando a estrutura e fisionomia local. Entretanto, queimadas podem reduzir os efeitos dos formigueiros nesses ambientes como, por exemplo, pela diminuição do forrageamento das formigas e, conseqüentemente, pela baixa incorporação de material orgânico ao solo. Este estudo testou o efeito do fogo sobre a concentração de nutrientes no solo de colônias de Atta laevigata em área de cerrado. A densidade de raízes foi maior nas colônias do que áreas controle, independentemente da presença do fogo. Na ausência de queimadas, as concentrações de nutrientes foram até 50 vezes superiores nos sauveiros. Contudo, queimadas reduzem a concentração de nutrientes e pH nas colônias. Possivelmente, essa baixa concentração seja atribuída à maior demanda pela vegetação remanescente, em resposta à perturbação provocada pelo fogo. Nesse caso, os efeitos negativos da herbivoria podem superar os benefícios causados por meio da disponibilização de nutrientes pelos sauveiros.

scholarly journals Horticulture affects macroinvertebrate assemblages in adjacent streams (Buenos Aires, Argentina)

2020 ◽  
pp. 5 ◽  
Author(s):  
Marina Arias ◽  
Ana Scalise ◽  
Marina Solis ◽  
Ariel Paracampo ◽  
Mercedes Indaco ◽  
...  
Keyword(s):  
Water Quality ◽  
Buenos Aires ◽  
Biosphere Reserve ◽  
Nutrient Concentrations ◽  
Buenos Aires Province ◽  
Macroinvertebrate Assemblages ◽  
Taxa Richness ◽  
Higher Taxa ◽  
High Nutrient ◽  
Pampean Streams

The agrochemicals used on crops can reach watercourses, affecting water quality and biologic communities. The aim of this research was to study the effects of horticulture on the water quality and invertebrate assemblages of adjacent streams in Buenos Aires province, Argentina. Four streams draining horticultural basins were compared with another four considered less disturbed: two of the latter located in a Biosphere Reserve and the other two in extensive livestock-raising basins. Pesticides were detected in the horticulture-related streams, while nutrient concentrations were significantly higher than in the less-disturbed streams. The macroinvertebrate assemblages differed: the less-disturbed streams exhibited a significantly higher taxa richness and density. Hyalella sp. and Simocephalus vetulus were dominant, whereas Entomobryoidea, Dugessidae, and Glossiphoniidae were dominant in the horticulture-associated streams. Ephemeroptera (Caenis and Baetidae) were well represented in the less-disturbed streams and rare or absent in the horticulture-adjacent streams. Multivariate analysis indicated that the horticulture-impacted sites contained high nutrient concentrations and tolerant taxa, while the less-disturbed sites corresponded to lower nutrient concentrations and sensitive taxa. We propose Hyalella sp. and S. vetulus as water-quality indicators in pampean streams and conclude that intensive agrochemical applications in horticulture increase nutrient and pesticide loads affecting the macroinvertebrate assemblages of adjacent streams.

Pesticides and Nutrients In Southern U. S. Shallow Ground Water and Surface Runoff

1993 ◽  
Vol 28 (3-5) ◽  
pp. 583-588 ◽  
Author(s):  
J. D. Schreiber ◽  
S. Smith ◽  
R. F. Cullum
Keyword(s):  
Surface Runoff ◽  
Shallow Groundwater ◽  
Nutrient Concentrations ◽  
Tillage Systems ◽  
No Till ◽  
Low Concentrations ◽  
Sediment Loss ◽  
High Nutrient ◽  
The Mean ◽  
Soil Insecticides

Nutrient and pesticide concentrations in shallow groundwater (3m) and surface runoff were determined for conventional-till (CT) and no-till (NT) soybean watersheds. Groundwater NO3N concentrations were similar for both tillage systems, averaging about 7-8 ppm, but exceeded 10 ppm for some storms. Annual mean groundwater NO3N concentrations were only 0.34 ppm in a riparian zone downslope from the CT watershed. Higher nutrient concentrations in NT surface runoff reflected surface residue leaching. Runoff from both watersheds, 2 days after a broadcast application of 0-20-20, had high nutrient concentrations that decreased during subsequent storms. Pesticide concentrations in groundwater of the NT watershed were as high as 250 ppb at a depth of 1.5 m within 1 week after application (1st rainfall). Concentrations beneath the CT watershed were &lt; 10 ppb maximum. One month after application, pesticide concentrations in groundwater beneath both watersheds had decreased to about 10% of their respective 1-week values. Similar total pesticide losses in runoff occurred for both tillage systems. NT reduced sediment loss but increased pesticide movement into the soil profile. Results of companion studies with corn at another site indicated similar trends for nutrients and pesticides in shallow groundwater. Within 11 months after application, herbicides were still detectable at very low concentrations (&lt;1 ppb). Soil insecticides, applied at planting, were not found in groundwater. Herbicides and insecticides were detectable in both the water and sediment phases of runoff for 5 months after application. At the 1.5-m depth, the mean NO3N concentration in groundwater for conventional-, reduced-and no-till corn was 4.78 ppm compared with 6.96 ppm at the 3-m depth.

Relationships among nutrients, algae, and land use in urbanized southern California streams

2006 ◽  
Vol 63 (12) ◽  
pp. 2621-2638 ◽  
Author(s):  
Lilian B Busse ◽  
Juliet C Simpson ◽  
Scott D Cooper
Keyword(s):  
Land Use ◽  
Total Phosphorus ◽  
Algal Biomass ◽  
Southern California ◽  
Stream Water ◽  
Algal Growth ◽  
Nutrient Concentrations ◽  
Total Chlorophyll ◽  
Impervious Surfaces ◽  
High Nutrient

We surveyed algal cover, algal biomass, and physical and chemical factors at 14 sites representing a range of land use types in the Malibu Creek watershed in southern California, USA. We also conducted nutrient diffuser substrate experiments to identify the nutrient limiting algal growth. Algal biomass increased with urbanization, reaching very high levels in the most urbanized streams (up to 322.4 mg chlorophyll a·m-2). Total nitrogen, total phosphorus, and benthic and total chlorophyll concentrations were positively correlated with the proportion of upstream land covered by impervious surfaces. Relationships between land use and algal biomass or nutrient concentrations were evaluated at 100 m, 500 m, and whole subwatershed scales. The closest relationships were found at the 500 m scale, where 56% of the variation in total chlorophyll could be explained by the proportion of land within a 500 m radius upstream covered by impervious surfaces. Floating macroalgae were observed in the summer in pools with high nutrient and light levels, whereas benthic algal biomass was positively related to total phosphorus concentrations and current speed. Other methods of determining nutrient limitation (nutrient diffuser substrate experiment, molar N/P ratios in stream water) produced conflicting results, possibly because algal growth was saturated by high nutrient levels at some of the study sites.

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