Avoimeen dataan perustuvan jokivirtaamatyökalun arvo Kaakkois-Aasiassa

Water governance deals with a substance that is essential for sustaining life. Managing a physical substance, which runs in multiple interconnected systems crossing administrative borders of all scales, creates controversies when the interests of different stakeholders collide. Creating policies and making decisions related to water requires efficient science-policy interaction, to which environmental modelling is inarguably an important input that provides salient, credible, and legitimate information to be used. However, modelling the endless complexity of the physical world leaves the modelers facing uncertainties. This work demonstrates the environmental modelling process, conducts an uncertainty quantification, and finally investigates the potential of adopting open-source solutions as a part of environmental modelling and policy support. This work applies both quantitative and qualitative methods. The main quantitative methods are hydrostreamer, a newly developed open-source tool that can estimate river streamflow, and Monte Carlo simulation, which is applied to quantify a type of uncertainty related to hydrostreamer. Within the qualitative methods, a survey and semi-structured interviews are applied to assess the current state of hydrostreamer and its applicability in the 3S river basin located in Southeast Asia, and also to investigate the potential of open-source based environmental modelling solutions in a more general manner. In the work, one of the contributors of uncertainty related to modelling streamflow with hydrostreamer is quantified and shown to behave with respect to Strahler order. Minor applications for hydrostreamer in its present state are found in the study area, and potential for adopting open-source solutions is shown, primarily due to low costs and through major donor organizations. In the resulting discussion, it is emphasized that trade-offs between modelling tool applicability and accuracy should be addressed to make the environmental modelling process truly open, instead of limiting the openness to only few of those with the required capabilities. Evaluating uncertainties related to a modelling process helps building confidence on the methods used; however, it should be considered carefully how to present the analysis and results for those who are not familiar with the subject. The work is a technical approach with ultimate goals in incorporating non-technical people and arguing for open data and transparency. It is concluded that open-source tools exhibit potential to be incorporated in complicated policy-making contexts despite the fact that no single tool can provide a panacea for complex issues.Vesi on keskeinen elämää ylläpitävä aine, ja sen merkitys lähes kaikille elinkeinoille on hyvin suuri. Se kiertää luonnon toisiinsa liittyneissä järjestelmissä jatkuvasti, ja vesivarojen hallinnoinnin on kyettävä toimimaan hallinnollisten rajojen yli. Veden käyttöön liittyy usein intressiristiriitoja eri toimijoiden välillä. Tieteellistä tietoa ja ympäristömallintamista hyödynnetään päätöksenteossa vesialalla, jolloin tuotetun tiedon tulisi olla mahdollisimman hyödyllistä ja luotettavaa. Fyysisen maailman loputon monimutkaisuus kuitenkin aiheuttaa epävarmuutta mallintamiseen. Tässä työssä esitellään ympäristömallintamisen prosessi ja arvioidaan erästä epävarmuustekijää numeerisesti. Lopuksi arvioidaan avoimeen lähdekoodiin perustuvien ratkaisujen potentiaalia osana ympäristömallintamista ja päätöksenteon tukea. Tässä työssä käytetään sekä laskennallisia että laadullisia menetelmiä. Laskennallisia menetelmiä ovat hydrostreamer, uusi avoimeen lähdekoodiin perustuva työkalu jokivirtaaman arviointiin, ja Monte Carlo -simulaatio, jota käytetään epävarmuuden simuloimiseen ja arviointiin. Kyselytutkimusta sekä puolistrukturoituja haastatteluja sovelletaan hydrostreamerin nykytilan ja sovellettavuuden arviointiin käyttäen nk. 3S-jokilaaksoa Kaakkois-Aasiassa esimerkkialueena. Työn tuloksena näytetään arvioidun spatiaalisen epävarmuuden käyttäytyvän käänteisesti Strahlerin luvun suhteen. Pienimuotoisia sovelluskohteita hydrostreamerille osoitetaan olevan tutkimusalueella, ja avointen työkalujen käyttöä ympäristömallintamisessa arvioidaan laadullisten tulosten perusteella. Työn pohdinnassa korostetaan, että mallintamistyökalujen valinnassa ja käytössä tulisi ottaa huomioon kompromissit sovellettavuuden ja tarkkuuden välillä. Tällöin mallinnusprosessista tulisi aidosti avoin sen sijaan, että avoimuus rajoittuisi vain pienelle joukolle toimijoita, joilla on tarvittava osaaminen ja data käytössään. Mallinnukseen liittyvien epävarmuuksien analysointi auttaa rakentamaan luottamusta kehitettyihin menetelmiin: epävarmuusanalyysin toteutus ja tulosten esittäminen muille voivat kuitenkin olla haastavia ja vaativat huolellista suunnittelua. Työ on lähtökohtaisesti tekninen, mutta sen pohjalta voidaan myös saada ei-teknisiä toimijoita osallistumaan mallintamiseen entistä enemmän. Yhteenvetona voidaan todeta, että potentiaalia sisällyttää avoimet työkalut osaksi monimutkaisia päätöksentekoprosesseja on olemassa, vaikkakaan mikään työkalu ei voi yksinään ratkaista kaikkia ongelmia

Food system by-products upcycled in livestock and aquaculture feeds can increase global food supply

Optimizing biomass use by reducing food-feed competition is paramount to achieving sustainable food systems. This study assesses global food systems in terms of livestock and aquaculture feed use and the availability of food system by-products and residues to quantify the potential for replacing food-grade feeds with food system by-products. Many livestock and aquaculture feeds compete for resources with food production. Increasing the use of food system by-products and residues as feed could reduce this competition. We gathered data on global food system material flows for crop, livestock and aquaculture production, focusing on feed use and the availability of by-products and residues. We then analysed the potential of replacing food-competing feedstuff-here cereals, whole fish, vegetable oils and pulses that account for 15% of total feed use-with food system by-products and residues. Considering the nutritional requirements of food-producing animals, including farmed aquatic species, this replacement could increase the current global food supply by up to 13% (10-16%) in terms of kcal and 15% (12-19%) in terms of protein content. Increasing the use of food system by-products as feed has considerable potential, particularly when combined with other measures, in the much-needed transition towards circular food systems.Peer reviewe

Notable shifts beyond pre-industrial streamflow and soil moisture conditions transgress the planetary boundary for freshwater change

Human actions compromise the many life-supporting functions provided by the freshwater cycle. Yet, scientific understanding of anthropogenic freshwater change and its long-term evolution is limited. Here, using a multi-model ensemble of global hydrological models, we estimate how, over a 145-year industrial period (1861–2005), streamflow and soil moisture have deviated from pre-industrial baseline conditions (defined by 5th–95th percentiles, at 0.5° grid level and monthly timestep over 1661–1860). Comparing the two periods, we find an increased frequency of local deviations on ~45% of land area, mainly in regions under heavy direct or indirect human pressures. To estimate humanity’s aggregate impact on these two important elements of the freshwater cycle, we present the evolution of deviation occurrence at regional to global scales. Annually, local streamflow and soil moisture deviations now occur on 18.2% and 15.8% of global land area, respectively, which is 8.0 and 4.7 percentage points beyond the ~3 percentage point wide pre-industrial variability envelope. Our results signify a substantial shift from pre-industrial streamflow and soil moisture reference conditions to persistently increasing change. This indicates a transgression of the new planetary boundary for freshwater change, which is defined and quantified using our approach, calling for urgent actions to reduce human disturbance of the freshwater cycle

Quantifying Earth system interactions for sustainable food production via expert elicitation

Several safe boundaries of critical Earth system processes have already been crossed due to human perturbations; not accounting for their interactions may further narrow the safe operating space for humanity. Using expert knowledge elicitation, we explored interactions among seven variables representing Earth system processes relevant to food production, identifying many interactions little explored in Earth system literature. We found that green water and land system change affect other Earth system processes strongly, while land, freshwater and ocean components of biosphere integrity are the most impacted by other Earth system processes, most notably blue water and biogeochemical flows. We also mapped a complex network of mechanisms mediating these interactions and created a future research prioritization scheme based on interaction strengths and existing knowledge gaps. Our study improves the understanding of Earth system interactions, with sustainability implications including improved Earth system modelling and more explicit biophysical limits for future food production

Identifying Key Drivers of Peatland Fires Across Kalimantan's Ex-Mega Rice Project Using Machine Learning

Throughout Indonesia ecological degradation, agricultural expansion, and the digging of drainage canals has compromised the integrity and functioning of peatland forests. Fragmented landscapes of scrubland, cultivation, degraded forest, and newly established plantations are then susceptible to extensive fires that recur each year. However, a comprehensive understanding of all the drivers of fire distribution and the conditions of initiation is still absent. Here we show the first analysis in the region that encompasses a wide range of driving factors within a single model that captures the inter-annual variation, as well as the spatial distribution of peatland fires. We developed a fire susceptibility model using machine learning (XGBoost random forest) that characterizes the relationships between key predictor variables and the distribution of historic fire locations. We then determined the relative importance of each predictor variable in controlling the initiation and spread of fires. The model included land-cover classifications, a forest clearance index, vegetation indices, drought indices, distances to infrastructure, topography, and peat depth, as well as the Oceanic Nino Index (ONI). The model performance consistently scores highly in both accuracy and precision across all years (>75% and >67.5% respectively), though recall metrics are much lower (>25%). Our results confirm the anthropogenic dependence of extreme fires in the region, with distance to settlements and distance to canals consistently weighted the most important driving factors within the model structure. Our results may help target the root causes of fire initiation and propagation to better construct regulation and rehabilitation efforts to mitigate future fires.Peer reviewe

Downscaling runoff products using areal interpolation: a combined pycnophylactic-dasymetric method

Abstract: Hydrological models are commonly forced with variables describing climate. These variables are often obtained from climate models, requiring processing via interpolation or downscaling in order to be useful for the hydrological modelling study. Outputs from climate – as well as hydrological – models are generally expressed as spatially explicit fields, but the results from hydrological models are rarely interpolated or downscaled. There can be many reasons for this. For instance, the existing model output may be of incompatible spatial units (raster, when vector needed, or vice versa), or of a different scale (regional, where local scale is needed). Runoff generation is a local process which is determined by the influx of water, landuse, vegetation and soil characteristics, and there have been many applications of its interpolation to watersheds, river lines or as continuous fields. However, most of the methods employed in runoff interpolation are statistical and do not account for process characteristics in runoff generation in the interpolation step. Here we present a novel spatial interpolation method for the purpose of downscaling coarse resolution runoff products based on areal interpolation. Areal interpolation is a process where a variable from a source zone is reallocated to overlapping target zones. We combine two advanced methods: Dasymetric Mapping (DM), which is simple Area weighted Interpolation (AI) informed by an ancillary variable, and Pycnophylactic Interpolation (PP), which is designed to refine the spatial distribution of a variable within the source zone. Each of these methods preserve mass balance – the volume of runoff from source zone is preserved in the target zones. Our methodology can address the Modifiable Area Unit Problem (MAUP) – a statistical bias caused by the sensitivity of analytical results of spatial data to levels of aggregation (the scale effect), as well as the arbitrary sizes, shapes, and arrangements of zones (the zoning effect). Addressing MAUP enhances usability of existing model results for runoff estimation because the zoning can be modified to fit the needs of a new analysis. The method is also able to take into account the spatial distribution of characteristics which govern runoff generation in the interpolation step. To test the methodology, we downscale a coarse global runoff product, LORA (Linear Optimal Runoff Aggregate), on to 126 Australian catchments with natural flow regimes, and compare how AI, DM, PP and the combined PP-DM fare against streamflow records. A recently developed topographical index, DUNE (Dissipation Per Unit Length), which is able to distinguish topographies with different runoff regimes, is used as the ancillary variable in DM and PP-DM. We assume that runoff is highly correlated with precipitation and we assume it can be interpolated with a smooth function. We also assume that topography can inform us about the actual distribution of runoff generation within a source zone (the spatial unit in a runoff product). We find that the simple AI method is more efficient in replicating the runoff profile in arid catchments where potential evapotranspiration is higher than precipitation. However, as precipitation increases and aridity is reduced, DM and PP-DM prove more efficient in replicating the recorded runoff. Using DUNE as the ancillary variable also results in higher performance in catchments with variable topography and performs worse in less variable terrain. In catchments with a high range of slopes, DM and PP-DM utilizing DUNE are consistently better than AI or PP, which do not utilize DUNE. Additionally, we find that in wet catchments which are located entirely within a single source zone of runoff, the performance is higher using DM, PP, and PP-DM than with the simple AI. In catchments which are covered by multiple source zones there is no clear benefit in using the more advanced areal interpolation methods over AI. Our results show that the method is able capture the spatial variability of runoff generation, but this requirescareful selection of the ancillary variable or a combination of ancillary variables. It is also evident from the results that arid and wet catchments require a different approach in runoff downscaling. Further investigation with a larger sample is needed to fully understand the properties of the downscaling methods.Peer reviewe

Future Transboundary Water Stress and Its Drivers Under Climate Change : A Global Study

| openaire: EC/H2020/819202/EU//SOS.aquaterraVarious transboundary river basins are facing increased pressure on water resources in near future. However, little is known ab out the future drivers globally, namely, changes in natural local runoff and natural inflows from upstream parts of a basin, as well as local and upstream water consumption. Here we use an ensemble of four global hydrological models forced by five global climate models and the latest greenhouse-gas concentration (RCP) and socioeconomic pathway (SSP) scenarios to assess the impact of these drivers on transboundary water stress in the past and future. Our results show that population under water stress is expected to increase by 50% under a low population growth and emissions scenario (SSP1-RCP2.6) and double under a high population growth and emission scenario (SSP3-RCP6.0), compared to the year 2010. As changes in water availability have a smaller effect when water is not yet scarce, changes in water stress globally are dominated by local water consumption—managing local demand is thus necessary in order to avoid future stress. Focusing then on the role of upstream changes, we identified upstream availability (i.e., less natural runoff or increased water consumption) as the dominant driver of changes in net water availability in most downstream areas. Moreover, an increased number of people will be living in areas dependent on upstream originating water in 2050. International water treaties and management will therefore have an increasingly crucial role in these hot spot regions to ensure fair management of transboundary water resources.Peer reviewe

Root zone soil moisture in over 25% of global land permanently beyond pre-industrial variability as early as 2050 without climate policy

Funding Information: This research has been supported by the Aard- en Levenswetenschappen, Nederlandse Organisatie voor Wetenschappelijk Onderzoek (grant no. 016.Veni.181.015) and the H2020 European Research Council (grant no. ERC-2016-ADG 743080). Ruud J. van der Ent received funding from the Netherlands Organisation for Scientific Research (NWO), project no. 016.Veni.181.015. Lan Wang-Erlandsson received financial support from the European Research Council through the Earth Resilience in the Anthropocene project (grant no. ERC-2016-ADG 743080). Publisher Copyright: © 2023 En Ning Lai et al.Root zone soil moisture is a key variable representing water cycle dynamics that strongly interact with ecohydrological, atmospheric, and biogeochemical processes. Recently, it was proposed as the control variable for the green water planetary boundary, suggesting that widespread and considerable deviations from baseline variability now predispose Earth system functions critical to an agriculture-based civilization to destabilization. However, the global extent and severity of root zone soil moisture changes under future scenarios remain to be scrutinized. Here, we analysed root zone soil moisture departures from the pre-industrial climate variability for a multi-model ensemble of 14 Earth system models (ESMs) in the Coupled Model Intercomparison Project Phase 6 (CMIP6) in four climate scenarios as defined by the shared socioeconomic pathways (SSPs) SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5 between 2021 and 2100. The analyses were done for 43 ice-free climate reference regions used by the Intergovernmental Panel on Climate Change (IPCC). We defined "permanent departures"when a region's soil moisture exits the regional variability envelope of the pre-industrial climate and does not fall back into the range covered by the baseline envelope until 2100. Permanent dry departures (i.e. lower soil moisture than pre-industrial variability) were found to be most pronounced in Central America, southern Africa, the Mediterranean region, and most of South America, whereas permanent wet departures are most pronounced in south-eastern South America, northern Africa, and southern Asia. In the Mediterranean region, dry permanent departure may have already happened according to some models. By 2100, there are dry permanent departures in the Mediterranean in 70% of the ESMs in SSP1-2.6, the most mitigated situation, and more than 90% in SSP3-7.0 and SSP5-8.5, the medium-high and worst-case scenarios. North-eastern Africa is projected to experience wet permanent departures in 64% of the ESMs under SSP1-2.6 and 93% under SSP5-8.5. The percentage of ice-free land area with departures increases in all SSP scenarios as time goes by. Wet departures are more widespread than dry departures throughout the studied time frame, except in SSP1-2.6. In most regions, the severity of the departures increases with the severity of global warming. In 2050, permanent departures (ensemble median) occur in about 10% of global ice-free land areas in SSP1-2.6 and in 25% in SSP3-7.0. By the end of the 21st century, the occurrence of permanent departures in SSP1-2.6 increases to 34% and, in SSP3-7.0, to 45%. Our findings underscore the importance of mitigation to avoid further degrading the Earth system functions upheld by soil moisture.Peer reviewe

Poor correlation between large-scale environmental flow violations and freshwater biodiversity: implications for water resource management and the freshwater planetary boundary

| openaire: EC/HE/819202/EU//SOS.aquaterra Funding Information: This research has been supported by the Canada First Research Excellence Fund (grant no. C150-2017-8). Funding Information: The authors acknowledge various funds that made this research possible. Chinchu Mohan received funding from the Canada First Research Excellence Fund (CFRE); Matti Kummu received funding from the Academy of Finland funded project WATVUL (grant no. 317320), the Academy of Finland funded project TREFORM (grant no. 339834), and the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement no. 819202). Vili Virkki received funding from the Aalto University School of Engineering Doctoral Program and the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement no. 819202). Sonja C. Jähnig acknowledges funding through the Leibniz Association for the project Freshwater Megafauna Futures. Miina Porkka received funding from European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement no. 819202). Lan Wang-Erlandsson was supported by the European Research Council through the “Earth Resilience in the Anthropocene” project (grant no. ERC-2016-ADG 743080) and by the IKEA Foundation. Publisher Copyright: © Copyright:The freshwater ecosystems around the world are degrading, such that maintaining environmental flow Environmental flow (EF): "The quantity, timing, and quality of water flows required to sustain freshwater and estuarine ecosystems and the human livelihoods and well-being that depend on these ecosystems."- Arthington et al. (2018). (EF) in river networks is critical to their preservation. The relationship between streamflow alterations (subsequent EF violationsEF violations are deviations in streamflow beyond the upper and lower boundaries of environmental flow envelopes (EFEs). The EFEs establish an envelope for acceptable EF deviations based on pre-industrial (1801-1860) stream discharge (see Sect. 2.2 for more details)) and the freshwater biodiversity response is well established at the scale of stream reaches or small basins (g 1/4<100g km2). However, it is unclear if this relationship is robust at larger scales, even though there are large-scale initiatives to legalize the EF requirement. Moreover, EFs have been used in assessing a planetary boundaryPlanetary boundary: planetary boundary defines biogeophysical planetary-scale boundaries for Earth system processes that, if violated, can irretrievably impair the Holocene-like stability of the Earth system. for freshwater. Therefore, this study intends to conduct an exploratory evaluation of the relationship between EF violation and freshwater biodiversity at globally aggregated scales and for freshwater ecoregions. Four EF violation indices (severity, frequency, probability of shifting to a violated state, and probability of staying violated) and seven independent freshwater biodiversity indicators (calculated from observed biota data) were used for correlation analysis. No statistically significant negative relationship between EF violation and freshwater biodiversity was found at global or ecoregion scales. These findings imply the need for a holistic bio-geo-hydro-physical approach in determining the environmental flows. While our results thus suggest that streamflow and EF may not be the only determinant of freshwater biodiversity at large scales, they do not preclude the existence of relationships at smaller scales or with more holistic EF methods (e.g., including water temperature, water quality, intermittency, connectivity, etc.) or with other biodiversity data or metrics.Peer reviewe