Luonnonmukaisen maatalouden fosforivirrat

Tämän tutkielman tavoitteena on arvioida Suomen luonnonmukaisen maatalouden fosforivirtojen volyymeja, lähteitä ja kohteita sekä virtoihin vaikuttavia tekijöitä. Tuloksia peilataan luomumaataloudelle asetettuun 20 % tavoitteeseen Suomen peltopinta-alasta. Tutkielman käytännön tavoitteena on tutkia, onko ravinteiden kierrätys suomalaisessa luomumaataloudessa riittävän kestävällä tasolla sekä löytää tarvittaessa käyttökelpoisia ratkaisuja luonnonmukaisen maatalouden kestävämpään ravinnetalouteen tulevaisuudessa. Tutkielman aineisto on kerätty BERAS -hankkeen puitteissa seitsemältä suomalaiselta ERA –tilalta (ecological recycling agriculture –tuotantotapa, ERA). Haastatteluaineiston, kansallisten tilastojen ja kirjallisuuden avulla havainnoista koottiin luomutiloja edustavat fosforitaseet ja tilojen sijainnin perusteella rajatun alueen luomutuotantoa edustava SFA -malli. Kolmen vaihtoehtoisen skenaarion ja tuloksien avulla muodostettiin arviot suomalaisen luomumaatalouden fosforitaseista ja -virroista vuonna 2020. Eteläsuomalainen luomumaatalous ei vaikuta hyödyntävän peltomaan fosforivarantoja, vaan turvautuu ostolannoitteisiin ja tavanomaiseen maatalouden tuottamiin ravinteisiin kuten lantaan ja teurasjätteistä valmistettuihin liha- ja luujauhoihin. Koska kotieläintiloja ei ole riittävästi suhteessa kasvinviljelytiloihin, luomumaatalouden lannantuotto ei riitä kasvintuotannon tarpeisiin. Fosforitaseeseen ei saada merkittävää parannusta vuoteen 2020 mennessä, ellei luomumaatalous ala hyödyntämään peltomaan fosforivarantoja. Samanaikaisesti tulee tukea muita kierrättäviä fosforivirtoja, joista tällä hetkellä potentiaalisimpia ovat vesistöjen biomassat. Elintarviketeollisuuden, yhdyskuntajätteiden ym. biomassojen suhteen tulee kehittää uudenlaisia toimintamalleja ja -tapoja, sekä punnita käytön ekologisia, sosiaalisia, taloudellisia ja terveydellisiä näkökulmia. Jos myös tavanomainen maatalous hyödyntää orgaanisia lannoitteita vuonna 2020, kuten hallituksen tavoitteissa on asetettu, orgaanisista lannoitevalmisteista kuten lannasta tulee entistä kysytympää, mikä voi edelleen heijastua eläintiheyteen, luomukasvien satotasoihin ja tuotannon kannattavuuteen

Capabilities of Baltic Sea models to assess environmental status for marine biodiversity

Abstract To date there has been no evaluation of the capabilities of the Baltic Sea ecosystem models to provide information as outlined by the Marine Strategy Framework Directive. This work aims to fill in this knowledge gap by exploring the modelling potential of nine Baltic Sea ecosystem models to support this specific European policy and, in particular, models' capabilities to inform on marine biodiversity. Several links are found between the Model-Derived Indicators and some of the relevant biodiversity-related descriptors (i.e. biological diversity and food webs), and pressures (i.e. interference with hydrological processes, nutrient and organic matter enrichment and marine acidification). However several gaps remain, in particular in the limited representation of habitats other than the pelagic that the models are able to address for descriptor sea-floor integrity and inability to assess descriptor non-indigenous species. The general outcome is that the Baltic Sea models considered do not adequately cover all the requested needs of the MSFD, but can potentially do so to a certain extent, while for some descriptors/ criteria/indicators/pressures new indicators and/or modelling techniques need to be developed in order to satisfactorily address the requirement of the MSFD and assess the environmental status of the Baltic Sea

Impacts of hydro-climatically varying years on ice growth and decay in a subarctic river

Predicting the future changes in river ice development and impacts on seasonal sediment transport requires more in-depth examination of present river ice cover growth processes. This paper therefore investigates: (1) the impacts of hydro-climatically varying years on river ice development in a Scandinavian subarctic meandering river and (2) the accuracy of existing analytical models for predicting ice thickness growth and ice decay. Stefan’s ice growth equation (version by Michel et al.) and Bilello’s ice decay equation are applied to varying hydro-climatic conditions experienced in the years 2013–2019. Estimates from these equations are compared with observed field conditions such as ice thicknesses, ice clearance dates and freeze-thaw days. Overall, the equations were most accurate in the winter of 2016–2017 when the maximum mid-winter snow thickness value was high, the number of freeze-thaw days was the closest to the long-term average of northern Scandinavia, and the rate of thermal snow-melt in the subsequent spring was slow. The equations would need to be adjusted to take into account expected future changes to conditions such as shorter winters, less snow formation and increased frequency of air temperatures crossing 0 °C

Impacts of Hydro-Climatically Varying Years on Ice Growth and Decay in a Subarctic River

Predicting the future changes in river ice development and impacts on seasonal sediment transport requires more in-depth examination of present river ice cover growth processes. This paper therefore investigates: (1) the impacts of hydro-climatically varying years on river ice development in a Scandinavian subarctic meandering river and (2) the accuracy of existing analytical models for predicting ice thickness growth and ice decay. Stefan's ice growth equation (version by Michel et al.) and Bilello's ice decay equation are applied to varying hydro-climatic conditions experienced in the years 2013-2019. Estimates from these equations are compared with observed field conditions such as ice thicknesses, ice clearance dates and freeze-thaw days. Overall, the equations were most accurate in the winter of 2016-2017 when the maximum mid-winter snow thickness value was high, the number of freeze-thaw days was the closest to the long-term average of northern Scandinavia, and the rate of thermal snow-melt in the subsequent spring was slow. The equations would need to be adjusted to take into account expected future changes to conditions such as shorter winters, less snow formation and increased frequency of air temperatures crossing 0 degrees C

Macro-Turbulent Flow and Its Impacts on Sediment Transport Potential of a Subarctic River during Ice-Covered and Open-Channel Conditions

Macro-turbulent flows (i.e., coherent flow structures reaching through the whole water column), have not been studied widely in northern seasonally frozen rivers during both open-channel and ice-covered flow conditions. Thus, we aim: (1) to detect and compare the macro-turbulent flow, both at open-channel and ice-covered flow conditions; (2) to explore spatial variation of macro-turbulent flow characteristics within a meander bend; and (3) to detect the effects of near-bed layer velocity fluctuation on bedload transport during differing overall flow conditions. The analyses are based on 5-10 min-long acoustic Doppler current profiler (ADCP) measurements from a subarctic river. The ice-covered low flow, and open-channel higher and lower flow conditions were measured over the period of 2016 to 2020. This study found that macro-turbulent flow existed at all measurement locations under both open-channel and ice-covered flow conditions. Macro-turbulent flow was most consistent and obvious in the streamwise velocity component, and in particular at the inlet and outlet of the investigated meander bend. During all seasons, the near-bed velocities consistently exceeded the sufficient amount for sediment transport. At inlet and outlet areas, the greatest near-bed velocity fluctuation across the critical threshold for sediment transport coincided with the measurement times having frequent macro-turbulent flow

Spatial variation of flow characteristics in a subarctic meandering river in ice-covered and open-channel conditions : A 2D hydrodynamic modelling approach

To be able to understand year-round river channel evolution both at present and in the future, the spatial variation of the flow characteristics and their sediment transport capabilities under ice cover need to be detected. As the measurements done through cross-sectional drill holes cover only a small portion of the river channel area, the numerical simulations give insight into the wider spatial horizontal variation of the flow characteristics. Therefore, we simulate the ice-covered flow with a hydrodynamic two-dimensional (2D) model in a meandering subarctic river (Pulmanki River, Finland) in mid-winter conditions and compare them to the pre-winter open-channel low flow situation. Based on the simulations, which are calibrated with reference measurements, we aim to detect (1) how ice-covered mid-winter flow characteristics vary spatially and (2) the erosion and sedimentation potential of the ice-covered flow compared to open-channel conditions. The 2D hydrodynamic model replicated the observed flow characteristics in both open-channel and ice-covered conditions. During both seasons, the greatest erosional forces locate in the shallow sections. The narrow, freely flowing channel area found in mid-winter cause the main differences in the spatial flow variation between seasons. Despite the causes of the horizontal recirculating flow structures being similar in both seasons, the structures formed in different locations depended on whether the river was open or ice covered. The critical thresholds for particle entrainment are exceeded more often in open-channel conditions than during ice-covered flow. The results indicate spatially extensive sediment transport in open-channel conditions, but that the spatial variability and differences in depositional and erosional locations increase in ice-covered conditions. Asymmetrical bends and straight reaches erode throughout the year, whereas symmetrical, smaller bends mainly erode in open-channel conditions and are prone to deposition in winter. The long ice-covered season can greatly affect the annual morphology of the submerged channel

River ice cover influence on sediment transportation at present and under projected hydroclimatic conditions

A large number of rivers are frozen annually and the river ice cover has an influence on the geomorphological processes. These processes in cohesive sediment rivers are not fully understood. Therefore, this paper demonstrates the impact of river ice cover on sediment transport, i.e. turbidity, suspended sediment loads and erosion potential, compared with a river with ice-free flow conditions. The present sediment transportation conditions during the annual cycle are analysed, and the implications of climate change on wintertime geomorphological processes are estimated. A one-dimensional hydrodynamic model has been applied to the Kokemäenjoki River in SW Finland. The shear stress forces directed to the river bed are simulated with present and projected hydro-climatic conditions. The results of shear stress simulations indicate that a thermally formed smooth ice cover diminishes river bed erosion, compared with an ice-free river with similar discharges. Based on long-term field data, the river ice cover reduces turbidity statistically significantly. Furthermore, suspended sediment concentrations measured in ice-free and ice-covered river water reveal a diminishing effect of ice cover on riverine sediment load. The hydrodynamic simulations suggest that the influence of rippled ice cover on shear stress is varying. Climate change is projected to increase the winter discharges by 27–77 % on average by 2070–2099. Thus, the increasing winter discharges and possible diminishing ice cover periods both increase the erosion potential of the river bed. Hence, the wintertime sediment load of the river is expected to become larger in the future

Kiintoaineen eroosio ja sedimentaatio virtavesissä - luonnollisesta prosessista virtavesien ongelmaksi

Valuma-alueiden eroosio ja vedessä kulkeutuvan kiintoaineen sedimentaatio ovat luonnollisia prosesseja virtavesissä. Ne ylläpitävät virtavesien elinympäristöjen monimuotoisuutta. Ihmistoiminta, erityisesti maankäyttö, on kuitenkin merkittävästi lisännyt eroosiota ja hienon kiintoaineksen määrää virtavesissä, millä on lukuisia haitallisia vaikutuksia virtavesien ekosysteemeihin. Tässä kirjallisuuskatsauksessa kuvataan virtavesien luontaisen sekä ihmistoiminnan muuttaman kiintoaineen eroosion ja sedimentaation merkitystä virtavesissä. Katsauksessa käsitellään liiallisen kiintoainekuormituksen ja sedimentaation vaikutuksia virtavesien perustuotantoon ja vesikasvillisuuteen, pohjaeläimiin, kaloihin sekä mikrobeihin ja hajotusprosesseihin. Lisäksi käsitellään kiintoainekuormituksen ja sedimentaation arvioinnin ja vesienhoidon kannalta keskeisiä seuranta-, vesiensuojelu- ja kunnostusmenetelmiä sekä tutkimustarpeita

Carbon and nutrient recycling ecotechnologies in three Baltic Sea river basins : the effectiveness in nutrient load reduction

There exist numerous ecotechnologies for recovery and reuse of carbon and nutrients from various waste streams before they are lost to runoff. However, it remains largely unknown how growing implementation of such ecotechnologies affect nutrient emissions to surface waters at catchment scale. Here, this knowledge gap is addressed by application of SWAT model in three case study catchments draining to the Baltic Sea: Vantaanjoki (Finland), Fyrisån (Sweden) and Słupia (Poland). Sustainability analysis with Multi-Criteria Analysis was applied in the stakeholder workshops in the case study areas to assess different ecotechnology alternatives. The following ecotechnologies received the highest sustainability scores: in Vantaanjoki anaerobic digestion, based on mostly agricultural residues; in Fyrisån source-separation of wastewaters; in Słupia nutrient extraction within the wastewater treatment process. The effect of application of digestate on agricultural soils in the Vantaanjoki catchment was simulated by adjusting the model parameters describing the organic carbon content and physical properties of soil. The results showed small reductions of nutrient loads to the Gulf of Finland. Larger reductions of nutrient loads to Lake Mälaren in Sweden and the Baltic Sea in Poland were achieved as a result of the wastewater treatment upgrades. In the Fyrisån catchment, higher relative reductions were simulated for TN than TP, and in dry years than in wet years. Although the studied ecotechnologies did not show as high effectiveness in nutrient load reduction as combinations of traditional Best Management Practices reported in literature, they do have other multiple benefits including crop yield increase, electricity, heat and bio-based fertilizer production

Using ecological models to assess ecosystem status in support of the European Marine Strategy Framework Directive

© 2015 The Authors. Published by Elsevier Ltd. The European Union's Marine Strategy Framework Directive (MSFD) seeks to achieve, for all European seas, "Good Environmental Status" (GEnS), by 2020. Ecological models are currently one of the strongest approaches used to predicting and understanding the consequences of anthropogenic and climate-driven changes in the natural environment. We assess the most commonly used capabilities of the modelling community to provide information about indicators outlined in the MSFD, particularly on biodiversity, food webs, non-indigenous species and seafloor integrity descriptors. We built a catalogue of models and their derived indicators to assess which models were able to demonstrate: (1) the linkages between indicators and ecosystem structure and function and (2) the impact of pressures on ecosystem state through indicators. Our survey identified 44 ecological models being implemented in Europe, with a high prevalence of those that focus on links between hydrodynamics and biogeochemistry, followed by end-to-end, species distribution/habitat suitability, bio-opt ical (remote sensing) and multispecies models. Approximately 200 indicators could be derived from these models, the majority of which were biomass and physical/hydrological/chemical indicators. Biodiversity and food webs descriptors, with ∼49% and ∼43% respectively, were better addressed in the reviewed modelling approaches than the non-indigenous species (0.3%) and sea floor integrity (∼8%) descriptors. Out of 12 criteria and 21 MSFD indicators relevant to the abovementioned descriptors, currently only three indicators were not addressed by the 44 models reviewed. Modelling approaches showed also the potential to inform on the complex, integrative ecosystem dimensions while addressing ecosystem fundamental properties, such as interactions between structural components and ecosystems services provided, despite the fact that they are not part of the MSFD indicators set. The cataloguing of models and their derived indicators presented in this study, aim at helping the planning and integration of policies like the MSFD which require the assessment of all European Seas in relation to their ecosystem status and pressures associated and the establishment of environmental targets (through the use of indicators) to achieve GEnS by 2020