Ecosystem deterioration in small lowland agricultural rivers that results from river dredging entails a significant threat to the appropriate ecohydrological conditions of these water bodies, ...expressed as homogenization of habitats and loss of biodiversity. Our study was aimed at a comparison of abundance and taxonomic structure of bottom-dwelling macroinvertebrates in dredged and non-dredged stretches of small lowland rivers and tributaries of the middle Narew River, namely: Czaplinianka, Turosnianka, Dab, and Slina. The experimental setup was (1) to collect samples of the bottom material from the river stretches that either persisted in a non-modified state (dredging was not done there in the last few years) or had been subjected to river dredging in the year of sampling; and (2) to analyze the abundance and taxonomic structure of macroinvertebrates in the collected samples. The study revealed that at the high level of statistical significance (from p = 0.025 to p = 0.001), the total abundance of riverbed macroinvertebrates in the dredged stretches of the rivers analyzed was approximately 70% lower than in non-dredged areas. We state that the dredging of small rivers in agricultural landscapes seriously affects their ecological status by negatively influencing the concentrations and species richness of benthic macroinvertebrates.
We studied distributions and abundances of macroinvertebrates in relation to hyporheic water exchange (HWE) patterns of the upper Biebrza − a small, lowland, low dynamic European river located in ...Northeast Poland. On a 6-km stretch of the river; we determined the variability of water exchange in the hyporheic zone by using direct field measurements of the pressure gradient to determine groundwater–surface water interactions. We identified locations with upwelling and downwelling fluxes of HWE as well as ambiguous hydraulic contact between groundwater and surface water along the river. In these locations, we sampled bottom-dwelling macroinvertebrates. In total, 627 individuals of benthic macroinvertebrates of 34 taxa were identified. We revealed that bottom-dwelling macroinvertebrate fauna is more abundant and diverse in river stretches where water from the river infiltrates the hyporheic zone. Results also show higher taxonomic richness and abundances of benthic macroinvertebrates in stretches with diagnosed infiltrating conditions (downwelling flux in a hyporheic zone) compared to in stretches where the river drained groundwater (upwelling flux in a hyporheic zone), but the recorded differences were not statistically significant.
Nous avons étudié la distribution et l'abondance des macroinvertébrés en relation avec les modèles d'échange d'eau hyporhéique (HWE) du cours supérieur de la Biebrza, une petite rivière européenne de plaine, peu dynamique, située dans le nord-est de la Pologne. Sur un tronçon de 6 km de la rivière, nous avons déterminé la variabilité des échanges d'eau dans la zone hyporhéique en utilisant des mesures directes sur le terrain du gradient de pression pour déterminer les interactions entre les eaux souterraines et les eaux de surface. Nous avons identifié les endroits présentant des flux ascendants et descendants d'HWE ainsi qu'un contact hydraulique ambigu entre les eaux souterraines et les eaux de surface le long de la rivière. Dans ces endroits, nous avons échantillonné des macroinvertébrés vivant sur le fond. Au total, 627 individus de macroinvertébrés benthiques de 34 taxons ont été identifiés. Nous avons révélé que la faune de macroinvertébrés vivant sur le fond est plus abondante et diversifiée dans les tronçons de rivière oú l'eau de la rivière s'infiltre dans la zone hyporhéique. Les résultats montrent également une plus grande richesse taxonomique et une plus grande abondance des macroinvertébrés benthiques dans les tronúons oú les conditions d'infiltration ont été diagnostiquées (flux descendant dans une zone hyporhéique) par rapport aux tronúons oú la rivière a drainé les eaux souterraines (flux ascendant dans une zone hyporhéique), mais les différences enregistrées n'étaient pas statistiquement significatives.
This book compares the lessons learned from a wetland-perspective approach to the changing climate and the requirements of the Water Framework Directive (WFD) with regard to environmental ...conservation. Examples from Germany and Poland are discussed due to the efficiency of their respective implementations of water conservation policies. Although the general scientific interest in specific issues such as wetlands, climate change, nature conservation and the WFD enjoy a well established position in international environmental research, these four elements are rarely considered together due to the complexity of the processes, biased scenarios of global change and subjective policy background. Major challenges involved in carrying out environmental conservation actions that assess the potential impacts of climate change and management plans on water bodies are identified. The results of this approach are addressed to practitioners in the field of adaptive management in a wetlands context.
•Technical measures of river maintenance induce decline of rivers' ecological status.•96% of analyzed studies revealed negative responses of biota to the maintenance of agricultural ...rivers.•Maintenance of agricultural rivers induces decline of abundance and species richness of biota.•Maintenance of agricultural rivers should be revisited in science and better managed in practice.
Display omitted
Intensification of agriculture and ongoing urban sprawl exacerbate pressures on rivers. Small rivers in agricultural landscapes are especially exposed to excessive technical actions implemented in order to allow for harvesting river water for irrigation, draining agricultural water and receiving sewage. Regular dredging and macrophyte removal strongly interfere with the global need for preserving river biodiversity that allows agricultural lowland rivers to remain refuges for a variety of species, and—accordingly—to keep water bodies resilient for the benefit of society. In order to provide a comprehensive look at the influence of agricultural lowland river management on the ecological status of these water bodies, we conducted a literature review and a meta-analysis. For the structured literature review we selected 203 papers reflecting on the response of aquatic ecosystems to dredging and macrophyte management actions. The database of scientific contributions developed for our study consists of papers written by the authors from 33 countries (first authorship) addressing dredging, macrophyte removal, status of fish and macroinvertebrates as well as the general ecological status of lowland agricultural rivers. We revealed that 96% of the analyzed papers indicated unilateral, negative responses of aquatic ecosystems, particularly macroinvertebrates, ichthyofauna and macrophyte composition, to maintenance measures. We revealed that studies conducted in the European Union on the ecological status of rivers appeared to significantly increase in quantity after the implementation of the Water Framework Directive. Finally, we concluded that day-to-day management of lowland agricultural rivers requires revision in terms of compliance with environmental conservation requirements and the recurrent implementation of technical measures for river maintenance.
While traditional forest management systems aim at maximizing timber production, sustainable forest management focuses on the multiple benefits of entire forest landscapes. The latter is now at the ...top of policy agendas. This calls for learning through evaluation to support the implementation of policies aiming towards multi-functional forest landscapes. The aim of this study is to quantify the economic trade-offs among natural, current, and re-wetted peatland forests using seven indicators, viz. drainage maintenance, rewetting, water retention, wood production, and three types of carbon sequestration as economic indicators. We discuss ways to adapt to and mitigate effect of forest draining on climate change toward securing multi-functional forest landscapes. The cost benefit analysis showed that in a potential natural state, Lithuania's peatland forests would deliver an economic benefit of ∼€176.1 million annually. In contrast, compared to natural peatland forests, the drainage of peatland forests for wood production has caused a loss of ∼€309 million annually. In comparison, peatland forest rewetting is estimated to increase the economic value by ∼€170 million annually. This study shows that satisfying different ecosystem services is a balancing act, and that a focus on wood production has resulted in net losses when foregone values of water storage and carbon sequestration are considered. Valuation of different sets of ecosystems service benefits and disservices must be assessed, and can be used as a tool towards creating, implementing and monitoring consequences of policies on both sustainability and biodiversity.
Display omitted
•Lithuanian drained peatland forests accrue losses of ∼€309 Million annually.•Landowner should not be economically or socially deprived by re-wetting peatlands.•Multifunctional forest landscapes require valuation of various ecosystems services.•Managing different portfolios of ecosystem services is a balancing act.
The purpose of the present research was to analyze the available data on river restoration projects in Europe. As the framework of our study, we conducted a structured international survey. We asked ...selected entities and experts from among those responsible for river restoration in European countries about the details and costs of European Union river restoration projects. We examined 119 river restoration projects that were implemented in Europe between 1989 and 2016; during the collection of data, some of the projects were still ongoing. Based upon the collected data we observed that the number of river restoration projects has been increasing since 1989, which expresses society’s growing interest in improving the quality of aquatic environments. We revealed that 56% of these European river restoration projects have been implemented by dedicated entities and stakeholders, not as part of any structured, larger-scale river restoration policy. This indicates that most European countries do not have integrated plans for river restoration. Our analysis showed that 52% of the projects analyzed have been designed and implemented without the participation of local stakeholders. It also showed that the budgets for river restoration projects did not differ significantly across various time horizons from 1989 to 2016. In our study, the average cost of restoring 1 ha of an European river was 310,000 euros (EUR). Considering these projects’ permanent assets and including their amortization, we calculated the average unit price of a river restoration’s value in terms of ecosystem meta-service to be 7757 EUR·ha−1·year−1.
Wetland buffer zones (WBZs) are riparian areas that form a transition between terrestrial and aquatic environments and are well-known to remove agricultural water pollutants such as nitrogen (N) and ...phosphorus (P). This review attempts to merge and compare data on the nutrient load, nutrient loss and nutrient removal and/or retention from multiple studies of various WBZs termed as riparian mineral soil wetlands, groundwater-charged peatlands (i.e. fens) and floodplains. Two different soil types (‘organic’ and ‘mineral’), four different main water sources (‘groundwater’, ‘precipitation’, ‘surface runoff/drain discharge’, and ‘river inundation’) and three different vegetation classes (‘arboraceous’, ‘herbaceous’ and ‘aerenchymous’) were considered separately for data analysis. The studied WBZs are situated within the temperate and continental climatic regions that are commonly found in northern-central Europe, northern USA and Canada. Surprisingly, only weak differences for the nutrient removal/retention capability were found if the three WBZ types were directly compared. The results of our study reveal that for example the nitrate retention efficiency of organic soils (53 ± 28%; mean ± sd) is only slightly higher than that of mineral soils (50 ± 32%). Variance in load had a stronger influence than soil type on the N retention in WBZs. However, organic soils in fens tend to be sources of dissolved organic N and soluble reactive P, particularly when the fens have become degraded due to drainage and past agricultural usage. The detailed consideration of water sources indicated that average nitrate removal efficiencies were highest for ground water (76 ± 25%) and lowest for river water (35 ± 24%). No significant pattern for P retention emerged; however, the highest absolute removal appeared if the P source was river water. The harvesting of vegetation will minimise potential P loss from rewetted WBZs and plant biomass yield may promote circular economy value chains and provide compensation to land owners for restored land now unsuitable for conventional farming.
Display omitted
•The efficiency of wetland buffer zones for nutrient retention was reviewed.•Organic and mineral soils as nutrient filters or sources were compared.•Processes driving phosphorus and nitrogen fluxes were described.•The indirect and direct impact of vegetation were unraveled.•Implications for wetland restoration and open research questions were specified.
•Inter-seasonal DGLF aligns with precipitation, revealing shifts in plant reliance.•Changing phreatophytes-induced cone of depression influences DGLF at landscape edges.•Proximity to peat-mineral ...interface shapes high-amplitude DGLF due to a pressure buffer.•River proximity dampens DGLF, validating hydraulic gradient influence at the hyporheic.
Diurnal groundwater level fluctuations (DGLF), closely tied to the metabolic rhythm of wetland vegetation, offer insights into direct groundwater consumption. This study is centered on exploring the spatial and temporal patterns of DGLF within the riparian aquifer of the Upper Biebrza region, motivated by the need to understand those sub-daily ecohydrological dynamics at play in this ecosystem, on a process-oriented scale. Through integrated spatiotemporal multivariate analysis, we aim to identify the key potential factors driving variations in these fluctuations across the landscape gradient, as well as, at different time scales. The study employed a comprehensive approach to gather data on groundwater heads and direct groundwater fluxes, utilizing high-temporal-resolution wells within a monitoring network. Meteorological variables from a dedicated station and high-resolution remote sensing maps were also integrated into the dataset. Analysis revealed distinct seasonal patterns and correlations in diurnal groundwater fluctuations, closely correlated with air temperature, solar radiation and subsequently vegetation phenology. Soil moisture content and summer rainfall events also influenced the intensity of these diurnal fluctuations. Dry periods intensified fluctuations, indicating an elevated reliance on groundwater by phreatophytes, while fluctuations decreased after rainfall events, signaling a shift in vegetation’s water source preference to soil moisture. Based on integrated data interpretation, a couple of potential mechanisms, reasonably forming the spatial variation pattern of DGLF, were formulated. Notably, the influence of local hydraulic gradients at transitional forest landscape edges, where higher amplitude fluctuations occurred, compared to lower fluctuations at midpoints. The proximity to the peat-mineral interface influences diurnal fluctuations, with wells closer to the interface showing sustained high-amplitude fluctuations driven by higher rates of recharge. Additionally, the influence of river proximity was explored, revealing dampened fluctuations in wells closer to the river due to rapidly changing hydraulic gradients. Further systematic experimentation, including numerical and data-driven modeling, is needed to validate these hypotheses. The study findings provide perspectives into (DGLF) patterns and distributions, enabling more accurate groundwater evapotranspiration (ETg) estimation and opening new avenues for considering ecohydrological feedback regarding carbon–water interaction, in relation to the daily-scale water table position.
Over the last decades observed climate change in Poland had a significant impact on the condition and functioning of the environment. Thus, it is crucial to analyze further future changes to be able ...to cope with the potential effects of changing climate conditions. In this study, we aimed to assess the impact of projected climate change on meteorological and hydrological conditions in the Biebrza Basin. We analyzed seasonal and annual changes in air temperature, precipitation, streamflow and flood characteristics using the hydrological Soil and Water Assessment Tool (SWAT) model. We examined projected changes for two future time horizons (2024–2050 and 2074–2100) under the Representative Concentration Pathways (RCP) 4.5 and 8.5 using an ensemble of nine EUROCORDEX model scenarios. Climate change projections indicated an increase in precipitation by up to +17 % (+117 mm) and air temperature by up to 3.8 °C by the end of the 21st century. In the analyzed flow gauges a considerable increase in low and mean flows is projected in the future. High flows are projected to slightly decrease for Sztabin, remain at a similar level for Dębowo and slightly increase for Osowiec and Burzyn. Flood area and volume will slightly increase in future horizons. The greatest increase in flood duration (by up to 16 days) is projected for RCP8.5 by the end of the 21st century. It seems, that the expected hydrological conditions, both in the short and long term, will become more stable and improve the conditions for the development of wetlands.
PDF
