Effects of released farmed mallards on species richness of breeding waterbirds and amphibians in natural, restored and constructed wetlands

Common practices in current game management are wetland restoration and creation, as well as releases of quarry species. We studied the impact of releases of mallard ducklings on species richness of wild waterbirds and amphibians on three types of wetlands: natural, constructed and restored. Data on species richness, macrophyte cover and water characteristics (total phosphorous and pH) were collected at 32 sites in an agricultural landscape in southern Sweden. In total, 14 species of waterbirds were recorded, ranging from zero to seven per wetland and survey. Amphibians were present in 24 of the 32 wetlands; in total five species were found, ranging from zero to three per wetland. By using generalized linear modelling we found that wetland type best predicted waterbird species richness. Constructed wetlands had significantly more waterbird species, regardless of whether they were used for mallard releases or not. There were breeding amphibians in 62% of natural, 100% of restored and 77% of constructed wetlands. Breeding amphibians were present in 84% of wetlands without, and in 62% of wetlands with releases. However, included variables did not explain amphibian species richness in the wetlands. Releasing large numbers of mallards on a wetland and providing food ad libitum is likely to affect water quality, nutrient availability and predation pressure. Indeed, phosphorous levels were significantly higher in release wetlands, but no differences were found between wetland types.This means that mallard releases may increase nutrient loads in environments that are already eutrophied. However, in our study system releases did not influence species richness of waterbirds and amphibians locally. Constructing wetlands for mallard releases can thus have positive local effects on species richness.Peer reviewe

Broadening the foundation for the study of childhood connectedness to nature

The spatial aspect of access to nature experience is considered a key factor for studying school-age educare and connectedness to nature. While the standard approach for questions of connectedness to nature is to study at the individual level using methods such as observations, psychometric scaling, and interviews, less common are spatial methods applied to structural or collective aspects of these questions; connectedness to nature study rarely considers the human relationship with nature across sociocultural/structural/institutional levels. Spatial analysis is presented as a step toward a broader consideration of connectedness to nature; careful consideration of connectedness to nature/disconnection must explore the forces beyond the individual shaping access and opportunity. Specifically, the study considers access through proximity to nature from school-age educare sites in the Swedish city of Malmö. Using spatial methodology, proximity to nature was measured at 67 school-aged educare sites. The results provide a complex picture of a range from high to low-quality access to nature for children at the sites. The results help highlight the importance of access via proximity while also opening the door to a mix of other sociocultural/structural/institutional factors to be considered in support of children’s access to nature experience

Teknisk slutrapport : en vik i Sjöriket Skåne

En vik i Sjöriket Skån

Teknisk slutrapport : en vik i Sjöriket Skåne

En vik i Sjöriket Skån

Inventeringsfiske i Arkelstorpsviken : 13-17 Augusti 2019

Arkelstorpsviken är en grund och kraftigt övergödd vik. Som efter sjö sänkningen är avskild från Oppmannasjön med en kanal på 1 km. Vid den norra stranden ligger samhället Arkelstorp. Under åren 2018-2020 driver Oppmanna Vånga byggderåd ett LEADER projekt tillsammans med Högskolan Kristianstad. Projektet syftar till att ta reda på varför sjön är kraftigt övergödd och vad som är lämpliga åtgärder för att bättra vatten kvaliteten. Arkelstorpsviken är intressant då miljöövervakningen indikerar att stora mängder näringsämne lämnar vikennedströms. Dessa näringsämnen hamnar först i Ivösjön men sedan i Hanöbukten.  Denna undersökning är gjord som del i LEADER projektet för att få en inblick hur den ekologiska statusen är i Arkelstorpsviken. 

Quantification of nutrient flux in a shallow freshwater lake in the south of Sweden

The nutrient load and export of nutrients from the lake "Arkelstorpsviken" in southern Sweden were monitored for one year (2019-04-01 to 2020-03-31). The purpose was to study whether the lake's eutrophication status is a symptom of internal load or caused by the load from the environment. The results can be used in a remediation plan for the heavily eutrophied lake Arkelstorpsviken, where extensive monitoring was carried out. Sampling stations in the main three upstream streams were set up to record the daily flow, supplemented by a 14-day sampling period for chemical analysis. In addition, small agricultural ditches and the local municipal treatment plant were monitored. Both total phosphorus and total nitrogen were reduced during transit through the lake. This indicates that the lake still acts as a nutrient sink contrary to the prevailing suspicion that the sediments are leaking phosphorus

Defining potential valuables through the characterisation of lake sediments : case study in Arkelstorp bay, Sweden

This study aims to characterise and discuss the potential use of sediment from the Arkelstorp bay located in the south of Sweden. Sediments from the Arkelstorp bay is collected and analysed on nutrient content, age, and potential contaminants. No organic environmental pollutants are found and the metal content are not elevated but still problematically high. For example, the amount of cadmium per phosphorus is 480 mg Cd kg(-1) P. However, as the carbon 14-datings showed, the sediment is preindustrial. Therefore, the amount of registered cadmium comes naturally from the surrounding environment. Arkelstorp sediments present the potential to become a source of nutrition in agriculture. The results show that the material is a good source of nutrients, with a nitrogen content of 18 g kg(-1) dry matter (DM), phosphorus 0.8 g kg(-1) DM and potassium 2.4 g kg(-1) DM respectively. However, the metal content is problematic to use the material without any pre-treatment. On the other hand, bioenergy production is expected to increase in the future, where this resource could potentially be helpful for the cultivation of bioenergy crops

Can wetlands reduce humic substances in forested streams : combining two approaches to characterize efficiency

Establishing statistical significance in assessing wetland performance can be quite challenging when reduction in the monitored substance is very small and temporarily variable. Assessing colour changes associated with humic substances is such a situation. One of the most important parameters of any evaluation of wetland treatment performances is the retention time of the water before it exit the wetland. This can be theoretically estimated, but even better measured directly with the help of a tracing agent. In this research, the approach is based on the simultaneously assessment of hydraulic retention time using conservative tracing (Rhodamine WT) and a mass balance based removal efficiency assessment (regression slope of the summation mass-in vs. summation mass-out)