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1.
Milan Strakraba Iva Dostlkov Josef Hejzlar Vojtêch Vyhnlek 《International Review of Hydrobiology》1995,80(3):403-413
The annual average degree of phosphorus retention (both TP and OP) in reservoirs was found to depend mainly on the theoretical retention time (RT). The phosphorus retention (RP) is shown for some reservoirs in Czech Republic to be well approximated (standard deviation = 10.9) with RP(TP) = 74.7* (1-exp(-0.0255* RT)) (N = 38, 7 ≤ RT ≤ 604 days). The inclusion of 13 additional reservoirs for which data were assembled from literature resulted in an almost identical relationship: RP(TP) = 76.1* (1-exp(-0.0282* RT)) (N = 51, range of RT nearly unchanged). The retention of soluble reactive phosphorus RP(OP) studied on data from literature seems to be higher than that of TP. Statistical comparison with data for RP(TP) of lakes has shown a significantly lower retention in lakes than in reservoirs for comparable RP, resulting in RP(TP) = 66.0* (1-exp(-0.00419* RT)) (N = 59, 5.8 ≤ RT ≤ 260000 days). The differences between RP(OP) and RP(TP) and differentiation of lakes and reservoirs are discussed and a need for more thorough theoretical analysis stressed. Consequences for watershed management are summarized. 相似文献
2.
A review and reassessment of lake phosphorus retention and the nutrient loading concept 总被引:3,自引:0,他引:3
1. We conducted a statistical reassessment of data previously reported in the lake total phosphorus (TP) input/output literature (n = 305) to determine which lake characteristics are most strongly associated with lake phosphorus concentration and retention. We tested five different hypotheses for predicting lake TP concentrations and phosphorus retention. 2. The Vollenweider phosphorus mass loading model can be expressed as: TPout = TPin/(1 + στw), where TPin is the flow‐weighted input TP concentration, τw is the lake hydraulic retention time and σ is a first‐order rate constant for phosphorus loss. 3. The inflow‐weighted TP input concentration is a moderately strong predictor (r2 = 0.71) of lake phosphorus concentrations when using log–log transformed data. Lake TP retention is negatively correlated with lake hydraulic retention time (r2 = 0.35). 4. Of the approaches tested, the best fit to observed data was obtained by estimating σ as an inverse function of the lake's hydraulic retention time. Although this mass balance approach explained 84% of the variability in log–log transformed data, the prediction error for individual lakes was quite high. 5. Estimating σ as the ratio of a putative particle settling velocity to the mean lake depth yielded poorer predictions of lake TP (r2 = 0.77) than the approach described above, and in fact did not improve model performance compared with simply assuming that σ is a constant for all lakes. 6. Our results also demonstrate that changing the flow‐weighted input concentration should always have a directly proportionate impact on lake phosphorus concentrations, provided the type of phosphorus loaded (e.g. dissolved or particulate) does not vary. 相似文献
3.
P. Verburg J. Horrox E. Chaney J. C. Rutherford J. M. Quinn R. J. Wilcock C. W. Howard-Williams 《Hydrobiologia》2013,718(1):119-130
Nutrient ratios have been related to nutrient limitation of algal growth in lakes. Retention of nutrients in lakes, by sedimentation and by denitrification, reduces the nutrient concentrations in the water column, thereby enhancing nutrient limitation. Differential retention of nitrogen and phosphorus alters their ratios in lakes and thereby contributes to determine whether nitrogen or phosphorus limits algal growth. We examined the relationships between differential nutrient retention, nutrient ratios, and nutrient limitation in Lake Brunner, a deep oligotrophic lake. The observed retention of nitrogen (20%) and phosphorus (47%) agreed with predictions by empirical equations from literature. As a result of differential retention with a much larger proportion of phosphorus retained than that of nitrogen, the nitrogen:phosphorus ratio was higher in the lake (69) than in the inflows (46). While the mean ratio in the inflows suggested no or only moderate phosphorus limitation, the lake appeared to be severely phosphorus limited. Combining empirical equations from literature that predict nitrogen and phosphorus retention suggests that the nitrogen:phosphorus ratio is enhanced by greater retention of phosphorus compared to nitrogen only in deep lakes with relatively short residence times, such as Lake Brunner. In contrast, in most lakes differential retention is expected to result in lower nitrogen:phosphorus ratios. 相似文献
4.
Phosphorus retention as a function of external loading,hydraulic turnover time,area and relative depth in 54 lakes and reservoirs 总被引:2,自引:0,他引:2
We analysed phosphorus retention as a function of external loading, hydraulic turnover time, area and relative depth on the
basis of published data from 54 lakes and reservoirs in different climate regions around the world. Our analysis demonstrated
that reservoirs and lakes that received higher areal loading of phosphorus (TPin) also retained more P per m2 but the proportion of the external P loading retained in the waterbody (retention coefficient, R
P) remained generally independent of TPin. The waterbodies with longer hydraulic residence times (T
R) retained larger proportions of external P and the correlation between R
P and T
R was much stronger in lakes with areas larger than 25 km2 than in the whole data set. TPin and T
R together determined 78% of the variation in R
P in large lakes. We also partially confirmed our hypothesis that waterbodies with bigger relative depths (Z
R) retain more of the external phosphorus than larger and shallower waterbodies with lower Z
R. The hypothesis was, however, validated only for lakes larger than 25 km2 and for those with T
R <0.3 year, where R
P increased significantly with increasing Z
R. In stratified lakes, increasing relative depth correlated with reduced P retention capacity, demonstrating the complex nature
of phosphorus biogeochemistry in lake ecosystems. 相似文献
5.
Substance budgets of an upland catchment: the significance of atmospheric phosphorus inputs 总被引:1,自引:0,他引:1
1. Precipitation inputs and outflow stream outputs are presented for 1993 in an upland lake and catchment system on the Antrim Plateau, Northern Ireland. 2. Phosphorus, potassium, chloride and possibly sulphate behaved conservatively inputs were approximately balanced by outputs. Combined nitrogen outputs were very much less than inputs, whereas there was a net export of calcium, magnesium, sodium and silica from the catchment. 3. Precipitation phosphorus inputs (22 kg P km?2yr?1) are compared with literature data and are shown to be near the median value. 4. The phosphorus budget is discussed in relation to the fact that there are few oligotrophic lakes in Northern Ireland. It is suggested this is due to the rainfall inputs, low phosphorus retention by the catchment and rapid flushing rates in the lakes. 相似文献
6.
An investigation of the phosphorus loading characteristics of 31 southern African man-made was lakes made. The lakes were characterized by low water retention times, with most of the lakes having retention times of less than one year. Catchment phosphorus export rates showed wide variation (1–162 mg P m-2 y-1) with those lakes experiencing excessive municipal wastewater inputs having export rates in excess of 53 mg m-2 y-1. The phosphorus data were tested against the Vollenweider (1976) and Dillon & Rigler (1974) phosphorus budget models which predict in-lake steady state concentrations of phosphorus. It was found that both models displayed good potential for the prediction of steady state concentrations of phosphorus, with better results being obtained from the Dillon & Rigler (1974) model. However, because phosphorus concentrations within these lakes may not necessarily be related to trophic status the use of these models as a predictive tool for eutrophication control still requires further development. 相似文献
7.
Research on epilimnetic phosphorus transformations in lakes had led to the establishment of a generalised picture which is promoted in reviews and textbooks. However, it would be wrong to believe that this established view can be applied to all lakes. Certainly the transformations of phosphorus in the summer epilimnia of small, coloured, humic forest lakes in southern Finland show features which deviate markedly from the generally accepted paradigm. (1) The plankton appears to be limited simultaneously by P and N rather than being strongly P limited. (2) Particulate P is typically a rather small fraction of the total P. (3) Molybdate reactive P may be a large part of the total P, although much of this MRP is not free orthophosphate, especially in highly humic lakes. (4) Turnover times for PO4-P are normally long (50–1000 minutes); turnover times appear to be longer in highly humic lakes. (5) Added 32 PO4 passes rapidly to macrozooplankton, apparently with rapid turnover of zooplankton phosphorus. (6) Sedimentation of phosphorus from the typically shallow epilimnion appears high, but may be partially compensated by biological retrieval of phosphorus from the phosphorus-rich hypolimnion. 相似文献
8.
Influence of internal loading on phosphorus concentration in shallow lakes before and after reduction of the external loading 总被引:2,自引:1,他引:1
An analysis of data from 49 shallow lakes showed, that the parameters of empirical models between phosphorus loading and concentration in the lake (e.g. Vollenweider type of relations) differ significantly for lakes without or with a reduced external loading. For lakes without a reduction of the external loading the summer phosphorus concentration is determined by the external phosphorus loading and the hydraulic loading. For these lakes the classical models suffice; deviations between calculations and measurements are partly due to errors made in the determination of the loading.In contrast, for lakes where the external loading was reduced, the measured internal loading explains most of the variation in the summer lake concentration. The external loading is of minor importance and the classical models cannot be applied. The internal loading measured before reduction of the external loading is not useful in predicting the concentration afterwards. Instead of the internal loading, the sediment composition can be used. The advantage of using sediment composition is that these variables are easier to determine and vary less in time. The most promising variable is the ratio between total P and total Fe in the sediment.Abbreviations: Qs
hydraulic loading (m y-1)
-
hydraulic retention time (y)
- Lext
external phosphorus loading (gP m-2 y-1)
- Lint
internal phosphorus loading (gP m-2 y-1)
- Plake
phosphorus concentration in the lake (gP m-3)
- Pinlet
phosphorus concentration in the inlet water (gP m-3)
- Psed
phosphorus content on the sediment (gP kg-1 d.w.)
- Fesed
iron content of the sediment (gFe kg-1 d.w.)
-
Y
dependent variable multiple regression calculations
-
X1, X2
independent variables multiple regressions calculations
-
a, a1
constants
-
a2, b
constants 相似文献
9.
Nutrient uptake and benthic regeneration in Danube Delta Lakes 总被引:1,自引:1,他引:0
Jana Friedrich Christian Dinkel Erwin Grieder Silviu Radan Dan Secrieru Sandra Steingruber Bernhard Wehrli 《Biogeochemistry》2003,64(3):373-398
We investigated the nutrient uptake capacity of three lakes (Uzlina, Matita and Rosu) within the Danube Delta during high water level in June and low water level in September 1999. Special emphasis was placed on nutrient cycling at the sediment-water interface and on the self-purification capacity of the lakes in the Danube Delta. In order to estimate the nutrient uptake of selected lakes we present in this paper the results of water analyses, benthic flux chamber experiments and deck incubation experiments of 15N-labeled sediment cores at the inflow and the outlet of the lakes. The external input of dissolved inorganic nitrogen and silica into the lakes decreases with increasing distance to the main Danube branches whereas the total dissolved phosphorus input is independent of the hydrological distance to the main branches. The nutrient loading is highest in the inflow channels, and decreases towards the outflow of the lakes. In June, the uptake of NO3
–, TDP and Si(OH)4 in the lakes was higher than in September. In contrast, NH4
+ uptake was more intense in September, when benthic release was more intense as well. On average, about 76% of the external plus internal nitrogen and phosphorus input into the lakes was taken up by macrophytes and phytoplankton during the growing season, whereas the uptake of external nutrient input amounted to about 43%. The benthic release of ammonia and silica increases from June to September and indicates, that part of the nutrients taken up during the growing season might be released during winter. We estimate the net impact of the Delta on the nutrient reduction of the Danube during the growing season is about 4.3%, assuming 10% of the Danube water is flowing through the Delta. 相似文献
10.
IRMGARD BLINDOW 《Freshwater Biology》1992,28(1):9-14
1. Charophytes have disappeared from several enriched lakes in Scania (southern Sweden) since the 1940s. Poor light conditions, rather than a toxic effect of phosphorus or negative impact of fish, are the most probable reason for this decline. 2. Small species of charophytes (shoot diameter 0.5–1.0 mm), which are able to form dense, low mats, still occur in eutrophic lakes with high phosphorus concentrations, but are restricted to areas of shallow water. In contrast, large species (shoot diameter 1–4 mm) have totally disappeared from the most turbid lakes. I suggest that these species are unable to grow in very shallow water because of damage by ice and wave action. 3. Maximum depth distribution (ze) and Secchi depth (D) were measured in Scanian lakes for both charophytes and angiosperms and combined with data obtained from Chambers & Kalff (1985). According to the combined data, zc and D are closely correlated with each other for both angiosperms and charophytes. 4. The zc of charophytes is higher than zc of angiosperms in clear lakes but lower in turbid lakes. Higher zc of angiosperms in the most turbid lakes is explained by special adaptations of these species to poor light availability (shoot elongation, canopy formation, rapid growth during spring). 相似文献
11.
D. W. Schindler 《Journal of phycology》1971,7(4):321-329
The question of nutrients responsible for eutrophication of freshwater lakes is reviewed, and recent additions to the literature on nutrient limitation are discussed. The paper by Lange is criticized on several grounds, including the facts that utilization of HCO3? by phytoplankton and the invasion of lake waters by atmospheric CO2 are ignored as sources of photosynthetic carbon. The phosphorus and nitrogen concentrations used in Lange's experiments are far higher than values published by others for Lakes Erie and Ontario. Preliminary results of fertilizing a small oligotrophic lake with nitrogen and phosphorus are described. The standing crop of phytoplankton increased by 30–50 ×, while the P:N:C ratio in seston did not change from ratios found in unfertilized lakes. Other experiments done in water columns isolated with polyethylene film showed that addition of carbon did not increase the phytoplankton standing crop. Since the fertilized lake was initially lower in total CO2 than any other recorded in the literature, it is concluded that carbon is unlikely to limit the standing crop of phytoplankton in almost any situation. Measurements of invasion of atmospheric gases to the fertilized lake by the Rn222 technique were compared with phytoplankton production measurements, revealing that atmospheric invasion of CO2 is sufficient to support the high phytoplankton standing crop in the epilimnion of the lake. Possible errors in interpretation of culture and bottle-bioassay experiments with respect to eutrophication are discussed. 相似文献
12.
Cycling of phosphorus (P) at the sediment/water interface is generally considered to be an abiotic process. Sediment bacteria are assumed to play only an indirect role by accelerating the transfer of electron from electron donors to electron acceptors, thus providing the necessary conditions for redox-and pH-dependent, abiotic sorption/desorption or precipitation/dissolution reactions. Results summarized in this review suggest that
- in eutrophic lakes, sediment bacteria contain as much P as settles with organic detritus during one year
- in oligotrophic lakes, P incorporated in benthic bacterial biomass may exceed the yearly deposition of bioavailable P several times
- storage and release of P by sediment bacteria are redox-dependent processes
- an appreciable amount of P buried in the sediment is associated with the organic fraction
- sediment bacteria not only regenerate PO4, they also contribute to the production of refractory, organic P compounds, and
- in oligotrophic lakes, a larger fraction of the P settled with organic detritus is converted to refractory organic compounds by benthic microorganisms than in eutrophic lakes.
13.
Nineteen small lakes located in open landscapes or deciduous forests in nutrient-rich calcareous moraines in North Zealand,
Denmark, were all net heterotrophic having negative net ecosystem production and predominant CO2 supersaturation and O2 undersaturation of lake waters. Forest lakes were poorer in nutrients, phytoplankton, and primary production, but richer
in dissolved organic matter and CO2 than open lakes with more light available. The modeled annual balance between gross primary production and community respiration
(GPP/R
COM) averaged 0.60 in forest lakes and 0.76 in open lakes and the ratio increased significantly with phosphorus concentration
and phytoplankton biomass but decreased with colored dissolved organic matter. The negative daily rates of ecosystem production
resembled estimates of oxygen uptake from the atmosphere to the lakes, whereas estimates of CO2 emission were 7.2-fold higher. Although CO2-rich groundwater and anaerobic respiration support greater molar release of CO2 than uptake of O2, we suggest CO2 emission is overestimated. Possible explanations include CO2 enrichment of the air film above small wind-sheltered lakes. The observed metabolism and gas exchange show that exogenous
organic matter is an important supplementary energy source to community respiration in these small lakes and that forest lakes,
in addition, experience pronounced light attenuation from trees and dissolved colored organic matter constraining primary
production.
Kaj Sand-Jensen (KSJ) formulated the original research idea and designed the study. Data analysis (ie. calculations, statistics
and figures) was performed by Peter A. Staehr (PAS). The text was for the most part written by KSJ, although with contributions
by PAS, especially in describing the applied methods and data analysis. 相似文献
14.
Lake restoration with and without dredging of phosphorus-enriched upper sediment layers 总被引:16,自引:3,他引:13
Joop Van der Does Pierre Verstraelen Paul Boers Jan Van Roestel Rudi Roijackers Gerard Moser 《Hydrobiologia》1992,233(1-3):197-210
Human activity has been the cause of continuing decline of water quality in most Dutch lakes. Development of lake restoration programmes must take into account the lake functions. Major reduction of the nutrient and pollutant loading is the primary step in lake restoration. Still, the recovery of eutrophic lakes is retarded frequently because of internal phosphorus loading by the lakes' sediments. Sediment dredging, as an additional tool for water quality management to accelerate accomplishing the desired water quality, is studied. In this paper we evaluate the preliminary results of eight lake restoration projects in the Netherlands. The lakes are compared in order to estimate the magnitude of the internal phosphorus loading. Dredging as an additional measure was carried out twice in the peatlake Geerplas. In the Nieuwkoop Lakes only the external phosphorus loading was substantially reduced from 0.9 to 0.2 g P m–2 y–1. Provisional results of these two shallow peatlake restoration projects focussed on eutrophication abatement with and without dredging, are presented. Both show a decrease in phosphorus concentration in the lakes. The necessity to dredge the lakes is discussed. 相似文献
15.
Milton L. Ostrofsky 《International Review of Hydrobiology》1978,63(4):481-499
Current empirical models used to predict phosphorus concentration from loading, retention and discharge data assume a phosphorus load which is constant in time. Such models are clearly inappropriate in relation to reservoirs. In a study of several lakes and a reservoir in western Labrador, the phosphorus budget model was found to be an excellent predictor of phosphorus concentration in the natural lakes, but seriously underestimated phosphorus concentration in the reservoir. Since leaching of nutrients from inundated soils and vegetation is generally considered to be the cause of trophic changes in reservoirs, a time dependent “leach loading” component was built into the steady state phosphorus budget model. This component not only allowed the budget to be balanced, but allowed the estimation of leaching coefficients describing the rate of phosphorus loss from submerged soils and vegetation. Using literature data from other reservoirs, the modified model predicted phosphorus dynamics consistent with other observed trophic status indicators. 相似文献
16.
Total phosphorus and total nitrogen explained a low percentage of summer chlorophyll variability in epilimnia of the Great Masurian Lakes. Division of the whole data set into two subgroups of lakes improved approximation of the chlorophyll nutrient relationship but revealed also functional differences between the lakes distinguished in that way. Chlorophyll in eutrophic lakes correlated well with nitrogen and phosphorus, that in mesotrophic lakes (those with summer chlorophyll <=22 mg m–3 as calculated in the model) was related to none of the nutrients. Higher summer chlorophyll content in epilimnetic waters was accompanied by higher chl:PP and chl:PN ratios. Algal adaptation to poor light conditions in eutrophic lakes is postulated as a possible reason for that difference.Chlorophyll – nutrient relationships varied with the trophic status of lakes. Epilimnetic chlorophyll strictly followed phosphorus changes in eutrophic lakes but did not do so in mesotrophic ones. Detailed comparison of selected meso- and eutrophic lakes showed marked differences in the seasonal changes of chlorophyll and nutrient concentrations and in sedimentation rates, especially in spring. Nutrient limitation rather than zooplankton grazing is suggested as a possible mechanism of controlling algal abundance and the sequence of spring events in a eutrophic lake. It is hypothesised that phosphorus turnover in eutrophic lakes is dominated by seasonal vertical fluxes, while in mesotrophic lakes it is more conservative with consumption and regeneration restricted mostly to metalimnion. Possible consequences of such conclusion are discussed in the paper. 相似文献
17.
Nutrient availability, in particular of phosphorus (P), is a key factor for the structure and functioning of shallow lakes, and not least the sediment plays an important role by acting as both a nutrient source and sink. We used 21 years of monthly mass balance and lake water data from six shallow (mean depth = 1.2–2.7 m) and fast flushed (mean hydraulic retention time = 0.6–2.6 months) eutrophic Danish lakes (mean summer P concentrations ranging from 0.09 to 0.61 mg/l) to investigate long-term trends in yearly and seasonal patterns of P retention. To one of the lakes, the external P input was reduced by 70% in the early 1990s, whereas none of the other lakes have experienced major changes in external P loading for more than 20 years. All lakes showed a distinct seasonal pattern with high P concentrations and typically negative P retention during summer (up to ?300% of the external loading from May to August). During winter, P retention was overall positive (up to 50% of the external loading from December to April). Internal P loading from the sediment delayed lake recovery by approximately 10 years in the lake with the most recently reduced external loading, but in all the lakes net release of P from the sediment occurred during summer. P release in the six lakes has not abated during the past decade, indicating that the sediment of eutrophic and turbid shallow lakes remains a net source of P during summer. The seasonal variations in P retention became more pronounced with increasing P levels, and retention decreased with increasing temperature, but increased if clear water conditions were established. 相似文献
18.
This study provides the most comprehensive physico-chemical and phytoplankton data yet available for Australian dune lakes,
which are among the world's most naturally acidic and oligotrophic freshwaters. Seasonal and spatial variations were examined
in Blue Lagoon and Lake Freshwater, two ‘water-table window’ lakes in south-east Queensland. Like other dune lakes, they are
acidic (minimum pH 4.20 and 4.55, respectively), polymictic water bodies with low concentrations of marine-derived major ions
and almost undetectable levels of trace metals. While linmologically similar in winter, during spring-summer Lake Freshwater
has significantly higher levels of chlorophyll-a, total phosphorus (TP) and turbidity than Blue Lagoon and other dune lakes, indicating seasonal mesotrophy. The key nutrient
is TP, which has recently increased to a maximum of 17 μ· l−1, due either to inputs from recreational sources, or to the death and decomposition of littoral vegetation resulting from
falling water levels over the last decade. Inorganic nitrogen, though present only in small amounts, does not appear to limit
the eutrophication process because of a shift in phytoplankton dominance from the usual desmids and dinoflagellates to N2-fixing blue-green algae.
A chlorophyll - TP linear regression derived for dune lakes indicates that at TP < 20 μg · l−1 chlorophyll ‘yield’ is higher than in other lake types represented by regressions from the literature. This may be due to
a more efficient utilization of the limited available phosphorus by dune lake algae which have adapted to the naturally oligotrophic
environment. The implications of these findings for lake management are discussed. 相似文献
19.
Relations between production and biomass of phytoplankton in four Swedish lakes of different trophic status and humic content 总被引:1,自引:1,他引:0
Ulf Heyman 《Hydrobiologia》1983,101(1-2):89-103
Production and biomass values from phytoplankton populations in four different Swedish lakes were analysed. The production in all lakes was directly proportional to biomass during homothermal periods. When the lakes were stratified there was a strong negative relation between specific growth rate and biomass. The data fitted to a logistic density dependent growth equation of the form: dB/ dt = µmB(1-B · K–1) where B is the biomass, µm the maximum specific growth rate and K the carrying capacity. The equation was used to derive the parameters µ · µm
–1 and carrying capacity (the maximum possible biomass). These parameters were then discussed in relation to light climate, phosphorus concentration and humic content. 相似文献
20.
Although salinity and aquatic biodiversity are inversely related in lake water, the relationship between types of salts and zooplankton communities is poorly understood. In this study, zooplankton species were related to environmental variables from 12 lakes: three saline lakes with water where the dominant anions were SO4 and CO3, four saline lakes with Cl-dominated water, and five dilute, subsaline (0.5–3 gl?1 total dissolved solids) lakes of variable anion composition. Although this study comprised only 12 lakes, distinct differences in zooplankton communities were observed among the two groups of chemically defined saline lakes. Canonical correspondence analysis identified total alkalinity, sulphate, chloride, calcium, sodium, potassium, and total phosphorus as all contributing to the first two ordination axes (λ1 = 0.97 and λ2 = 0.62, P<0.05). The rotifer Brachionus plicatilis and the harpactacoid copepod Cletocamptus sp. prevailed lakes with Cl-dominated water. In contrast, the calanoid copepods Leptodiaptomus sicilis and Diaptomus nevadensis were dominant in the SO4/CO3-dominated lake water with elevated potassium (79–128 mg l?1) and total phosphorus concentrations (1322-2915 μg l?1). The contrasting zooplankton species distribution among these two saline lake types is likely explained by variable selective pressure on zooplankton and their predators from differing physiological tolerances to salt stress and specific ions. While inland saline lakes with Cl as the dominant anion are relatively rare in Canada and SO4/CO3 are the common features, our study provided an opportunity to compare zooplankton communities across the two groups of lakes. 相似文献