Showing papers in "Wetlands Ecology and Management in 1992"
TL;DR: The biomass data, as well as increased rhizome specific weight and TNC concentrations, clearly suggests that “reloading” of rhizomes with energy reserves starts in June, not towards the end of the growing season as has been suggested previously.
Abstract: Seasonal changes in rhizome concentrations of total nonstructural carbohydrates (TNC), water soluble carbohydrates (WSC), and mineral nutrients (N, P and K) were monitored in two Phragmites australis stands in southern Sweden. Rhizome biomass, rhizome length per unit ground area, and specific weight (weight/ length ratio) of the rhizomes were monitored in one of the stands. Rhizome biomass decreased during spring, increased during summer and decreased during winter. However, changes in spring and summer were small ( 1000 g m−2). Concentrations and standing stocks of mineral nutrients decreased during spring/ early summer and increased during summer/ fall. Only N, however, showed a pattern consistent with a spring depletion caused by translocation to shoots. This pattern indicates sufficient root uptake of P and K to support spring growth, and supports other evidence that N is generally the limiting mineral nutrient for Phragmites. The biomass data, as well as increased rhizome specific weight and TNC concentrations, clearly suggests that “reloading” of rhizomes with energy reserves starts in June, not towards the end of the growing season as has been suggested previously. This resource allocation strategy of Phragmites has consequences for vegetation management. Our data indicate that carbohydrate reserves are much larger than needed to support spring growth. We propose that large stores are needed to ensure establishment of spring shoots when deep water or stochastic environmental events, such as high rhizome mortality in winter or loss of spring shoots due to late season frost, increase the demand for reserves.
125 citations
TL;DR: In this paper, the authors compared three-to-four-year old created palustrine/emergent wetland sites with five nearby natural wetlands of comparable size and type, and found that created sites exhibited more open water, greater water depth, and greater fluctuation in water depth than natural wetlands.
Abstract: Five three- to four-year old created palustrine/emergent wetland sites were compared with five nearby natural wetlands of comparable size and type. Hydrologic, soil and vegetation data were compiled over a nearly two-year period (1988-90). Created sites, which were located along major highways, exhibited more open water, greater water depth, and greater fluctuation in water depth than natural wetlands. Typical wetland soils exhibiting mottling and organic accumulation were wanting in created sites as compared with natural sites. Typha latifolia (common cattail) was the characteristic emergent vegetation at created sites, whereas a more diverse mosaic of emergent wetland species was often associated with Typha at the natural sites. Species richness was slightly higher in created (22–45) vs. natural (20–39) wetlands, but the mean difference (33 vs. 30) was not significant. Nearly half (44%) of the 54 wetland taxa found at the various study sites were more frequently recorded at created than natural wetlands. The presence of mycorrhizae in roots of Typha angustifolia (narrow-leaved cattail) and Phragmites australis (common reed) was greater at created than natural wetlands, which may be related to differential nutrient availability. Wildlife use at all sites ranged from occasional to rare, with more sightings of different species in the natural (39) than created (29) wetlands. The presence of P. australis and introduced Lythrum salicaria (purple loosestrife) may pose a threat to future species richness at the created sites. One created site has permanent flow-through hydrology, and its vegetation and wildlife somewhat mimic a natural wetland; however, the presence of P. australis and its potential spread pose an uncertain future for this site. This study suggests the possibility of creating small palustrine/emergent wetlands having certain functions associated with natural wetlands, such as flood water storage, sediment accretion and wildlife habitat. It is premature to evaluate fully the outcome of these wetland creation efforts. A decade or more is needed, emphasizing the importance of long term monitoring and the need to establish demonstration areas.
97 citations
TL;DR: The minimum information about a seed bank needed for a wetland restoration or creation project is a species list as mentioned in this paper, which can be used for determining the composition of seed banks: (1) mechanical separation of seeds from a volume of soil and (2) germination of seeds under appropriate environmental conditions.
Abstract: The minimum information about a seed bank needed for a wetland restoration or creation project is a species list. There are two basic techniques for determining the composition of seed banks: (1) mechanical separation of seeds from a volume of soil and (2) germination of seeds from a volume of soil under appropriate environmental conditions. The latter method always gives biased results. It is best to collect as many random samples as possible when sampling a wetland seed bank. These can be combined as needed for processing. Field studies in India have demonstrated that vestigial seed banks can be used to re-establish a former vegetation type in a monsoonal wet-land that had become overgrown by a species of grass. In less than a year, 9 of 1 I species in the vestigial seed bank were found growing in areas cleared of the grass. Vestigial seed banks of drained prairie wetlands in the northcentral United States contained a few wetland species after 70 years, although species diversity and seed density declined significantly after 20 to 30 years of drainage and cultivation. In Florida, U.S.A., wetlands have been established in strip-mined areas using donor soils from existing wetlands. Newly established wetlands quickly developed a dense cover of vegetation, although this vegetation often lacked many desirable wetland species. Experimental studies of soil moisture conditions using a seed bank from the Delta Marsh, Canada, demonstrated that soil moisture affected both the total number of seeds, and the relative proportion of seeds of each species that germinated from a seed bank. The density of seedlings of emergent wetland species in the treatments was directly proportional to soil moisture, while that of terrestrial annuals was inversely proportional. Emergent species made up nearly 90% of the seedlings in the wettest treatment and 0% in the driest.
91 citations
TL;DR: In this article, a coastal wetland along Lake Erie (Ohio, U.S.A.) was studied to determine hydrologic and phosphorus budgets and spatial and temporal variation of phosphorus and related chemical parameters.
Abstract: A coastal wetland along Lake Erie (Ohio, U.S.A.) was studied to determine hydrologic and phosphorus budgets and spatial and temporal variation of phosphorus and related chemical parameters. The wetland was influenced by changing Lake Erie water levels, seiches, shifting shoreline sediments, and watershed inflow during a year of severe drought. The water budget for a 7-month period (March – September, 1988) had average inflow of 15 200 m3 day−1 from the watershed and 3.5 m3 day−1 from Lake Erie. The wetland increased in volume by 700 m3 day−1 despite a drought that resulted in 80% more evapotranspiration than rainfall as a barrier beach isolated the wetland from Lake Erie for 77% of the study period. Conductivity decreased by 34% as water flowed through the wetland and turbidity and total suspended solids were variable and statistically similar at inflow and outflow. Average total phosphorus concentrations in the inflow and outflow were also similar (247 and 248 µg P l−1 respectively) although total soluble phosphorus and soluble reactive phosphorus decreased significantly (α=0.05) from inflow to outflow (averages 94 to 45 µg P l−1 and 7.5 to 4.0 µg P l−1 respectively). Nutrient budgets from field data estimate a retention of 36% of the phosphorus, presumably in the sediments (0.8 mg P m−2 day−1). A general nutrient retention model, an estimated deposition rate from a sediment core and a simulation model predicted higher mass retention of phosphorus but similar percentage retention.
52 citations
TL;DR: In this article, the authors studied the vegetation composition and structure of 58 sites along gradients in the valley mire of Biebrza, Poland, are related to physical and chemical variables of groundwater and peat.
Abstract: Vegetation composition and structure of 58 sites along gradients in the valley mire of Biebrza, Poland, are related to physical and chemical variables of groundwater and peat. The three most prominent hydrochemical processes in the valley are (a) dissolution of calcite; (b) dissolution of iron, manganese and aluminium; and (c) enrichment with nitrogen and potassium. Major factors determining these processes are vertical flow of the groundwater and river flooding. Within the rheophilous zone of the mire, calcium-richness of the shallow groundwater and base-saturation of the peat are caused by upward seepage of groundwater originating from adjacent higher grounds. This groundwater movement keeps the larger part of the mire saturated with calcium. Good correlations exist between hydrochemistry and vegetation patterns. Groundwater-fed sites support a characteristic rich fen vegetation (Caricetum limoso-diandrae) with a low biomass production. The flood-plain vegetation consists of highly-productive communities of Glycerietum maximae and Caricetum elatae. In a belt in the Upper Basin where neither flooding nor upward seepage occurs, succession, probably caused by intensified drainage, leads to a dwarf-shrub vegetation (Betuletum humilis; poor fen).
45 citations
TL;DR: In this paper, spatial associations of wetland loss rates in a 950-km2 study area in the southwestern Barataria basin of Louisiana's Mississippi River delta plain for four intervals spanning 40 years, 1945-1985, were determined.
Abstract: We determined spatial associations of wetland loss rates in a 950-km2 study area in the southwestern Barataria basin of Louisiana's Mississippi River delta plain for four intervals spanning 40 years, 1945–1985. A geographic information system was used to analyze spatial and temporal changes. Annual wetland loss rates increased over the 40 years; the rate of increase in annual rates accelerated through 1980 and then began to decelerate. The average annual rate of wetland loss for the entire study area increased from 0.2%/yr during 1945–1956, to 1.2%/yr for 1956–1969, 1.9%/yr for 1969–1980, and 2.0%/yr for 1980–1985. Wetland loss was not uniform throughout the study area. Eight sub-areas were identified as having different densities and/or causes of loss. Processes implicated in the differing loss rates include sea level rise, shoreline erosion, accelerated subsidence along natural levees, canal modification of hydrologic flows, interference of dredged material with sheet flow, and saltwater intrusion. In some areas, several processes are believed to operate together to induce wetland degradation and wetland loss.
37 citations
TL;DR: In this paper, the authors analyzed data from Section 404 permits issued in California from January 1971 through November 1987 that involved impacts to wetlands and required compensatory mitigation (wetland creation, restoration, or preservation).
Abstract: We analyzed data from Section 404 permits issued in California from January 1971 through November 1987 that involved impacts to wetlands and required compensatory mitigation (wetland creation, restoration, or preservation). The purpose of this study was to determine patterns and trends in permitting activity and to document cumulative effects of associated management decisions on the California wetland resource. The 324 permits examined documented that 387 compensatory wetlands (1255.9 ha) were required as mitigation for impacts to 368 wetlands (1176.3 ha). The utility of the data on wetland area was limited, however, since 38.0% of the impacted wetlands and 41.6% of the compensatory wetlands lacked acreage data. The wetland type most frequently impacted (37.8% of impacted wetlands) and used in compensation (38.2% of compensatory wetlands) was palustrine forested wetlands. Estuarine intertidal emergent wetlands had the most area impacted (52.3%) and compensated (62.5%). The majority of the wetlands were small (less than or equal to 4.0 ha in size). Wildlife habitat was the most frequently listed function of impacted wetlands (90.7% of the permits) and objective of compensatory wetlands (83.3%). Endangered species were listed as affected in 20.4% of impacted and 21.0% of compensatory projects. The number of permits requiring compensatory mitigation and the number of impacted and compensatory wetlands increased from 1971 to 1986.
33 citations
TL;DR: A conceptual model has been developed, of the likely impact of climate change and the resulting sea level rise, on British salt marsh vegetation, on the basis of the assumption that a rise in sea level will cause the drowning of certain existing vegetation zones and their subsequent replacement by new vegetation types appropriate to the changed sea level.
Abstract: The present relationship between sea level and the zonation of salt marsh vegetation is discussed in terms of the salt marshes of the Essex and Kent coasts. These marshes are already decreasing in area as a result of a number of different environmental pressures, including the sinking of the land relative to the sea, at a rate of about 3 mm per year, the result of isostatic adjustment following the last glaciation. Because most British salt marshes are backed by a sea wall the marshes can not respond to rising sea levels by migrating landwards, thus increasing the impact of sea level change. In view of this and of the importance of salt marshes as protection for the sea walls themselves, a conceptual model has been developed, of the likely impact of climate change and the resulting sea level rise, on British salt marsh vegetation. The basis of this approach is the assumption that a rise in sea level will cause the drowning of certain existing vegetation zones and their subsequent replacement by new vegetation types appropriate to the changed sea level. Estimates have been made of the likely impact of rises in sea level of 0.5, 1.0 and 1.5 metres on the five major vegetation zones identified in East Anglia. The validity of this approach is discussed, together with the likely additive effect of present degenerative changes observed in the Essex salt marshes. It is estimated that over the next 60 years a sea level rise of only 0.5 m, when existing degeneration is taken to account, would cause a loss of over 40% of the present area of salt marsh in Essex and probably also in Kent. These losses would mainly effect the higher salt marsh vegetation zones which would be replaced by pioneer communities. These predictions would be greatly magnified by larger rises in sea level. The wider ecological implication of these changes and some possible remedial measures are considered. These predictions are discussed in relation to the situation in the rest of East Anglia and for Britain as a whole.
32 citations
TL;DR: In this paper, the authors studied a rapidly subsiding Spartina alterniflora Lois in a salt marsh following the addition at 47 and 94 Kg m−2 of new sediment.
Abstract: Transpiration, leaf conductance, net photosynthesis, leaf growth, above-ground biomass and regeneration of new culms were studied in a rapidly subsiding Spartina alterniflora Lois. salt marsh following the addition at 47 and 94 Kg m−2 of new sediment. Plant growth was enhanced in response to sediment addition as was evident by a significant increase in leaf area, above-ground biomass production and regeneration of new culms (p ≤ 0.05). Leaf conductance and transpiration rates were significantly greater in sediment treated plants than in control plants (p ≤ 0.05). Enhanced production of culms per unit area of marsh resulted in increased leaf area which allowed a greater capacity for net photosynthesis and contributed to increases in above-ground biomass of sediment treated plots.
26 citations
TL;DR: The PAWN model DEMNAT is described, which is designed to predict the impact of hydrologic changes on terrestrial ecosystems in The Netherlands and the predicted effects of an assumed climatic change are discussed.
Abstract: Current water management policy in The Netherlands aims to serve a multitude of land use functions, such as agriculture, industry, shipping, and drinking water supply. To attune this policy to the diversity of functions, computer models are used to predict the consequences of various policy options as a part of PAWN: the government's Policy Analysis of Water management for The Netherlands. Nature conservation and development is a relatively new aspect of water management policy. This article describes the PAWN model DEMNAT, which is designed to predict the impact of hydrologic changes on terrestrial ecosystems in The Netherlands. The main components of the model are explained and the predicted effects of an assumed climatic change are discussed.
26 citations
TL;DR: In this article, the potential effects of greenhouse warming on the hydrology and salinity of isolated brackish waters are illustrated with a computer model, simulating several scenario's of climatic change and differently shaped waters.
Abstract: Thoughts about the potential effects of climatic change due to greenhouse warming on hydrophytes and hydrophyte communities in inland still waters of Europe are presented. A distinction is made between permanent and temporary shallow aquatic ecosystems and between freshwater and brackish systems. Potential effects of greenhouse warming on the hydrology and salinity of isolated brackish waters are illustrated with a computer model, simulating several scenario's of climatic change and differently shaped waters. In permanent waters, greenhouse warming may result in an earlier onset of growth of those hydrophytes in which the germination of propagules and the resumption of growth is primarily controlled by temperature. This may occur at the cost of macrophytes that have dormancy mechanisms regulated by environmental cues other than temperature (e.g. photoperiod). In addition, it seems plausible that because of milder winters, some thermophilous aquatic plants spread to the north. Furthermore, in culturally eutrophicated waters, in which the sediment compartment is heavily loaded with organic matter and/or nutrients, a rise in temperature may accelerate nutrient turn-over for several years, resulting in algal blooms and shifts in quality and quantity of macrophyte vegetation. Effects of greenhouse warming on temporary shallow waters will be more complex. Changes in temperature, precipitation and evaporation may lead to larger seasonal fluctuations in the water table and a more frequent or more prolonged period of desiccation. Some hydrophytes can cope with these circumstances, while others withstand desiccation only for a short period. Macrophyte communities may also be affected in an indirect way by periodic desiccation of their habitats. In emerged bottoms the rate of mineralization is probably higher than when overlying water is present. When water returns, a pulse of mineral nutrients may temporarily result in algal blooms and a high turbidity of the water, thus hampering hydrophyte growth. In addition, in isolated brackish waters an increased evaporation may result in larger fluctuations in salinity. In such a harsh environment species diversity of aquatic macrophytes will most probably decline.
TL;DR: In this article, the relation between climatic conditions and type of peatland ecosystem in different climate zones in Europe is discussed, and the hydrology of raised bogs in the sub-oceanic region is given.
Abstract: The relation between climatic conditions and type of peatland ecosystem in the different climate zones in Europe is discussed. Special attention is given to the hydrology of raised bogs in the sub-oceanic region. Possible effects of climatic change on such raised bog systems are discussed in terms of changes in water discharge, ground-water table, rate of peat accumulation, and flora and vegetation. It is concluded that future changes, as suggested by the more widely accepted scenarios for climatic change, will seriously disrupt the ecological functioning of these peatland ecosystems, and it is doubtful whether at least the most southerly examples of sub-oceanic raised bogs will at all survive. Finally, suggestions are given for future research on the impact of climatic change on peatland ecosystems.
TL;DR: In this article, a management plan using a watershed-scale approach was devised to limit loss of wetland functions in the one million ha Tensas Basin, Louisiana, U.S.A. The plan required two prior steps.
Abstract: A management plan using a watershed-scale approach was devised to limit loss of wetland functions in the one million ha Tensas Basin, Louisiana, U.S.A. Proposals to develop wetland areas are evaluated for their potential to affect the structure and function of the landscape as a whole. The plan required two prior steps. First, we assessed the structural and functional status of the landscape through time. Second, using the assessment, we formulated a set of environmental goals. The assessment indicated that the landscape is severely degraded; of the original forest, 85% has been lost, and the deforestation has negatively affected water quality and biota. Specific goals were devised to conserve remaining wetland resources and to restore functional integrity to the basin as a whole. On the basis of these two prior steps and principles of landscape ecology and conservation biology, we devised a plan that would establish two large tracts of bottomland forest (BLF) totaling 102 000 and 63 000 ha. These tracts would be established by reforesting about 1000 ha of corridors, primarily along streams, linking existing forest patches. In addition, set-back levees and man-made diversions would be incorporated to restore natural flooding to certain areas of remaining BLF. Existing wetlands would be prioritized on the basis of size and density of patches and placed in one of three management categories. Implementation of such a plan is possible under the present regulatory authority of U.S. federal government programs administered by regulatory agencies responsible for wetland protection.
TL;DR: The authors summarizes expected changes in hydrology, chemistry and biota of Dutch peatlands (bogs, fens and moorland pools) caused by climatic changes resulting from the Greenhouse Effect.
Abstract: This paper summarizes expected changes in hydrology, chemistry and biota of Dutch peatlands (bogs, fens and moorland pools) caused by climatic changes resulting from the Greenhouse Effect. Special attention is paid to the interaction with atmospheric acid deposition. In both bogs and moorland pools prolonged drought periods may cause deleterious effects on biota because of the release of atmospherically-derived reduced sulphur compounds. In fenlands negative changes will be caused by eutrophication due to increased supply of allochtonous water. Long-term water and nutrient budgets are needed, along with better predictions of expected climate changes, to develop models of changes in hydrology, chemistry and biota of peatlands.
TL;DR: In this article, an early successional wetland complex on a reclaimed surface coal mine in southern Illinois was studied 1985-1987, and the authors found that biomass was low, with above-ground values of 10−210g m−2 and below-ground biomass of 1.5−2435 g m −2.
Abstract: An early successional wetland complex on a reclaimed surface coal mine in southern Illinois was studied 1985–1987. Seasonally, biomass was low, with above-ground values of 10–210g m−2 and below-ground biomass of 1.5–2435 g m−2. Biomass peaked in spring and did not vary much throughout the remainder of the growing season. Stem densities were high (179–1467 m−2) because large numbers of seedlings became established as falling water levels exposed large areas of mudflats. Fluctuating water levels led to a lack of community zonation. Species diversity (H′) was low to moderate over all sites with diversity values ranging between 1.86 and 3.27.
TL;DR: Timing of oil spills would be important, but impact would depend on species composition of the seed bank and colonizing vegetation, dispersal of seeds into the site, and germination requirements.
Abstract: The effect of oil spills on the recruitment of freshwater tidal wetland species was determined using soil seed bank samples collected in early March from two New Jersey Delaware River marshes Samples were exposed to simulated tidal cycles 0 (2 days), 2 and 4 wk after soil was collected: 0 wk samples were treated before germination began Oil treatment significantly reduced survival to 1 May (end of study) of Acnida cannabina and Bidens laevis, the dominant species, as well as number of species per sample and height of B laevis Total perennial seedlings, present in low numbers, also showed significant reduction with treatment However, during the course of the study, Peltandra virginica recruitment and survival were not reduced by oil treatment and recruitment of Sagittaria latifolia appeared enhanced There was no consistent pattern regarding which treatment time produced the greatest effect Interactions (site, treatment, time) were generally not significant Because these tidal freshwater wetlands and seed banks are dominated by annuals, reduction in seedling numbers and growth could substantially alter vegetation patterns Timing of oil spills would be important, but impact would depend on species composition of the seed bank and colonizing vegetation, dispersal of seeds into the site, and germination requirements
TL;DR: In this paper, the authors discuss the dilemma of choosing between allowing increased desiccation of wetlands as the climate becomes drier or increasing the distribution of Rhinewater and the potential ecological effects of these choices.
Abstract: The dry summer of 1976 triggered a wholesale installation of sprinkler systems for agriculture. This dry summer also revealed areas in The Netherlands most susceptible to drought, namely sandy regions and the coastal fringe. This resulted in distribution of Rhine water to new areas, and in quantities hitherto unknown. The Second National Water Management Plan (1982) consequently focussed on enlarging the capacity of water distribution works. This distribution has led to a multitude of ecological effects, such as changes in salinity and nutrient concentration, as well as the spreading of contaminants. Consequently, the Third National Water Management Plan (1990) includes fewer distribution works because of the adverse environmental effects and the reduced feasibility due to increasing costs and decreasing agricultural benefits. A climatic change as predicted may result in climatic conditions in The Netherlands resembling those of France or the Mediterranean, implying drier summers and more precipitation in winter. An increased frequency of dry summers will no doubt revive water distribution plans now shelved and may even bring new ones to the drawing board. An increase in Rhine water distribution will have serious consequences for many aquatic and terrestrial ecosystems, as will a lowering of the groundwater table. In this paper we will discuss the dilemma of choosing between allowing increased desiccation of wetlands as the climate becomes drier or increasing the distribution of Rhinewater and the potential ecological effects of these choices. Alternative strategies to water management also are discussed.
TL;DR: It is concluded that many migratory bird species will be influenced by climatic change, leading to adaptations in the birds annual cycle.
Abstract: This paper presents an assessment of the possible effects of future climatic change on migratory birds The assessment is based on two approaches: firstly an inventory is made of the environmental factors that may change which directly affect migratory birds These factors include physical (temperature, hydrology, ocean and air streaming patterns) as well as biological (floral and faunal composition of ecosystems) and landuse aspects of the environment
TL;DR: In this article, the predicted increase in atmospheric carbon dioxide and the effects of global warming will influence the Wadden Sea, The Netherlands, an area of exceptional ecological value, and the effect of CO2 fertilization on marine primary production remains to be elucidated.
Abstract: The predicted increase in atmospheric carbon dioxide and the effects of global warming will influence the Wadden Sea, The Netherlands, an area of exceptional ecological value. The direct effect of elevated atmospheric CO2 on terrestrial coastal ecosystems is either marginal or unknown. The slight acidification of the sea which is predicted might have an impact on primary producers and juvenile animals. The effect of CO2 fertilization on marine primary production remains to be elucidated. Profound changes will occur if sea level rises at the predicted rate of 60 cm per century, as sedimentation rates will be insufficient to maintain the salt marshes on the barrier islands. The marshes of the mainland coast will be impoverished, as high and low marshes are not expected to continue to coexist at the same locations. As sediment supply to the Wadden Sea is sufficient to compensate for sea level rise, the estuarine character of the Wadden Sea, with sand- and mudflats, is expected to remain largely unchanged.
TL;DR: In this paper, a sampler for collection of interstitial water from wetland sediments is described, which facilitates in situ measurement of a wide range of abiotic parameters such as electrical conductivity, redox potential, and pH.
Abstract: A sampler for collection of interstitial water from wetland sediments is described. It differs from other sampling devices because it does not have to be filled with solution to facilitate diffusion, it does not have to be removed from the wetland to collect samples, and it can be used to draw repeated samples over time from identical locations. The device facilitates “in situ” measurement of a wide range of abiotic parameters such as electrical conductivity, redox potential, and pH in wetland sediments. The device has application in ecological investigations of sediment-borne wildlife diseases, studies of benthic invertebrates, measurement of nutrient exchange, and other aspects of wetland ecology.
TL;DR: There are two major potential effects of rising atmospheric temperature on freshwater wetlands: direct effects, and indirect effects of a rising sea level as discussed by the authors, and a holistic, intuitive view is more likely to produce realistic scenarios for the future than one based on reductionism.
Abstract: There are two major potential effects of rising atmospheric temperature on freshwater wetlands: direct effects, and indirect effects of rising sea level. Direct effects are varied, but muted by the high specific heat of water and the key dependence of freshwater production on nutrients rather than temperature. However, there may be effects on lake stratification, fish distribution and restoration of lakes by biomanipulation. Rising sea levels have the potential to alter lowland riverine lakes very considerably by saline influx. A holistic, intuitive view is more likely to produce realistic scenarios for the future than one based on reductionism.
TL;DR: In this article, the impact of climatic change on variables of concern to eco-hydrology was examined and the long time series of records of temperature, precipitation and river flow for Poznan were analyzed and forecasts of tendencies were made.
Abstract: The impact of climatic change on variables of concern to eco-hydrology was examined. Long time series of records of temperature, precipitation and river flow for Poznan were analyzed and forecasts of tendencies were made. Spatial distribution of runoff and of the ratio of evapotranspiration to precipitation was obtained for the country. It was found likely that the dynamics of the hydrological cycle will accelerate. Annual precipitation, runoff and evapotranspiration will increase. The joint effect, including estimated growth in water demand, is likely to be a decrease in the amount of soil moisture.