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Internationales Bodenfeuchtemessnetz (ISMN) - Ein Service der In-situ-Bodenfeuchtedaten global sammelt, harmonisiert und dauerhaft bereitstellt

Veranlassung Der Betrieb des ISMN an der TU Wien wurde seit seiner Implementierung im Jahr 2009 auf Projektbasis durch die Europäische Weltraumagentur (ESA) finanziert. Durch die Initiative des ICWRGC und der BfG wurde eine langfristige Finanzierung und neue Heimat des ISMN in Deutschland unter Mitwirkung des Bundesministers für Verkehr und digitale Infrastruktur a. D. Andreas Scheuer sichergestellt. Somit wurde im Jahr 2021 begonnen, den Transfer an ICWRGC/BfG vorzubereiten und neues Personal zu akquirieren. Der Transfer soll bis Ende 2022 abgeschlossen sein und der Produktionsbetrieb aufgenommen werden. Ziele - Das bedeutendste Ziel des ISMN ist die Bereitstellung und Dissemination von In-situ-Bodenfeuchtedaten. Diese Daten werden qualitätsgeprüft und harmonisiert frei zur Verfügung gestellt. Neben der Bereitstellung der Daten fungiert das ISMN als Langzeitarchiv für globale Bodenfeuchtedaten und konsolidiert diese in einer Datenbank. Dafür werden Daten von verschiedensten Datenanbietern mit unterschiedlichen Formaten prozessiert und in die Datenbank eingepflegt. Für einige der Daten erfolgt dies als kontinuierlicher Prozess, sodass Bodenfeuchtedaten als Fast-Echtzeitprodukt abgerufen werden können. Bodenfeuchte ist von großer Bedeutung für die Produktivität von Pflanzen und die Gesundheit von Ökosystemen. Somit hat sie entscheidenden Einfluss auf das Wasserdargebot für die Nahrungsmittelproduktion. Zusätzlich ist die Bodenfeuchte ein wichtiger Steuerfaktor für die Partitionierung von Energie- und Wasserflüssen an der Landoberfläche. Die Verfügbarkeit von langen Zeitreihen dieser Variable ermöglicht es Wissenschaftlern, Anwendern (z.B. Landwirte) und Entscheidungsträgern, Trends zu erkennen, den Einfluss des globalen Wandels abzuschätzen und Adaptionsstrategien zu entwickeln. Das ISMN stellt dauerhafte, harmonisierte und qualitätsgesicherte In-situ-Bodenfeuchtemessungen frei zur Verfügung. Zu diesem Zweck akquiriert und konsolidiert es global verfügbare Bodenfeuchtedaten.

Land rights, Social capital and investments in sustainable management practices and productivity enhancing inputs in Ghana

The proposed research project aims at analyzing the impacts of land tenure rights and social capital on farmers' investments in sustainable management practices and productivity-enhancing inputs. The theoretical emphasis on the benefits from more secure land rights is at variance with the empirical literature, particularly in Sub-Saharan Africa. Meanwhile a growing body of empirical evidence suggests that social capital and especially social networks may be equally important in promoting investments. Even some linkages between social capital and land tenure rights have been identified. However, very little empirical work is available on these linkages and how they both influence farmers' investment in sustainable management practices. The proposed research project intends to contribute to closing these gaps by specifying a comprehensive model of farmers' investment behavior that considers both the impacts of land tenure arrangements and social capital on investment and farm productivity. The empirical analysis will make use of data being collected in the Brong-Ahafo region of Ghana. Econometric models will analyze interdependencies and the influence of land tenure rights and social capital on investment and farm productivity. Qualitative analysis of perceived needs of the farmers will be undertaken to complement the econometric analysis.

Maschinelles Lernen zur Verbesserung der geothermischen Energieerzeugung, Teilvorhaben: Ermittlung der hydrochemischen und anlagentechnischen Parameter zur Interpretation, Bedarfsermittlung, Modellerstellung und -validierung

Die Energiewende hin zu erneuerbaren Energien ist eine der größten sozioökonomischen Herausforderungen in Europa. Rund die Hälfte der Energie wird in Form von Wärme benötigt, wovon nur ca. 20 % im Moment aus erneuerbaren Energiequellen stammt. Ein wichtiger Bestandteil zur vollständigen Wärmeabdeckung durch erneuerbare Energieressourcen ist die hydrothermale Geothermie. Dabei ist die nachhaltige Verfügbarkeit ein wichtiges Thema. Ziel des Projektes MALEG ('Machine Learning for Enhancing Geothermal energy production') ist es, ein maschinell lernendes Vorhersageprogramm zu entwickeln, das in Verbindung mit neuen verfahrenstechnischen Anlagen die Möglichkeit schafft, Produktivität und Wirtschaftlichkeit von Geothermieanlagen deutlich zu verbessern. Ziel ist es, die Möglichkeiten einer stärkeren Temperaturabsenkung für eine Kaskadennutzung zu analysieren und anlagentechnisch zu ermöglichen unter Berücksichtigung eines nachhaltigen Reservoir Managements. Basierend auf standortspezifischen Eigenschaften wie Temperatur, Reservoirdruck oder Thermalwasserchemie, sollen die optimalen Betriebsparameter ermittelt werden, um damit auch die Betriebssicherheit über lange Zeiträume zu gewährleisten. Das Ziel des Teilprojektes der Hydroisotop ist die Charakterisierung der Thermalwässer der drei am Projekt beteiligten Geothermieanlagen, die Evaluierung von möglichen störenden, die Anlagen gefährdenden Prozessen sowie die Ermittlung möglicher Prozesse bei möglichen Veränderungen der Betriebsparameter. Die Ermittlung der hydrochemischen Parameter sowohl in der Anlage als auch während der Demonstratorexperimente bildet die Grundlage für die Validierung und Kalibrierung der hydrochemischen Modelle und des Inputs für die maschinellen Lernprogramme und -modelle.

Impact of elevated nitrogen inut on the biogeochemistry and productivity of tropical forests (NITROF) - Effects of enhanced N deposition on productivity and structure of a tropical montane rainforest in Panama

Nitrogen deposition in tropical areas is projected to increase rapidly in the next decades due to increase in N fertilizer use, fossil fuel consumption and biomass burning. As tropical forest ecosystems cover about 17 percent of the land surface and are responsible for about 40 percent of net primary production, even small changes in N (and consequently C) cycling can have global consequences. Until now studies an consequences of enhanced N input in tropical forest ecosystems have been very limited and even very rarely addressed its deleterious effects to the environment. There is undoubtedly a huge discrepancy between the expected increase in N deposition in the tropics and the present knowledge an how tropical forest ecosystems will react to this extra input of reactive N. Our research aims at quantifying the changes in processes of N retention (plant growth, biotic and abiotic N immobilization in the soil) and losses (gaseous N losses, nitrification, denitrification, leaching of different forms of dissolved N). Implementation of policy and management tools, like the international trading of carbon credits under the Kyoto Protocol, need researches that allow us to better understand the consequences of environmental change (N deposition) an forest productivity. Our research will have important implications for predicting future responses of forest C cycle to changes in N deposition, and for the role of N deposition in tropical forests to affect potential feedback mechanisms of CO2 fertilization and climate change.

Optimierung der Produktivität Leguminosen basierter Anbausysteme und der Bodenmikrobiologie über die Integration mikrobieller Präparate und bioaktiver Pflanzenstoffe, Teilvorhaben: Nährstoffkreisläufe im Boden

Schwerpunktprogramm (SPP) 1158: Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; Bereich Infrastruktur - Antarktisforschung mit vergleichenden Untersuchungen in arktischen Eisgebieten, Investigation of mechanism driving glacial/interglacial variability in stratification/mixing and biological productivity of the Pacific Southern Ocean and potential implications on air-sea CO2-exchange: synthesis of climate and ocean biogeochemical modeling with paleoceanographic reconstructions

Atmospheric CO2 concentrations present a repetitive pattern of gradual decline and rapid increase during the last climate cycles, closely related to temperature and sea level change. During the Last Glacial Maximum (LGM; 23-19 kyr BP), when sea level was ca. 120 m below present, the ocean must have stored additionally about 750 Gt carbon. There is consensus that the Southern Ocean represents a key area governing past and present CO2 change. The latter is not only of high scientific but also of socio-economic and political concern since the Southern Ocean provides the potential for an efficient sink of anthropogenic carbon. However, the sensitivity of this carbon sink to climate-change induced reorganizations in wind patterns, ocean circulation, stratification, sea ice extent and biological production remains under debate. Models were not yet able to reproduce the necessary mechanisms involved, potentially due to a lack of the dynamic representation/resolution of atmospheric and oceanic circulation as well as missing carbon cycling. Data on past Southern Ocean hydrography and productivity are mainly from the Atlantic sector, thus do not adequately document conditions in the Pacific sector. This sector is not only the largest part of the Southern Ocean, but it also represents the main drainage area of the marine-based West Antarctic Ice Sheet (WAIS). In the proposed study we aim to generate paleo-data sets with a newly established proxy method from sediment core transects across the Pacific Southern Ocean. This will enhance the baselines for the understanding and modeling of the Southern Ocean's role in carbon cyling, i.e. ocean/atmosphere CO2 exchange and carbon sequestration. It will also allow insight into the response of the WAIS to past warmer than present conditions. Paired isotope measurements (oxygen, silicon) will be made on purified diatoms and radiolarians to describe glacial/interglacial contrasts in physical and nutrient properties at surface and subsurface water depth. This will be used to test (i) the impact of yet unconsidered dust-borne micronutrient deposition on the glacial South Pacific on shifts of primary productivity, Si-uptake rates and carbon export, (ii) the 'silicic-acid leakage' hypothesis (SALH) and (iii) the formation and extent of surface water stratification. Diatom and radiolarian oxygen isotopes will provide information on the timing of surface ocean salinity anomalies resulting from WAIS melt water. Climate model simulations using a complex coupled atmosphere ocean general circulation model (AOGCM) in combination with a sophisticated ocean biogeochemical model including Si-isotopes will be used for comparison with the paleo records. The analysis will cover spatial as well as temporal variability patterns of Southern Ocean hydrography, nutrient cycling and air-sea CO2-exchange. With the help of the climate model we aim to better separate and statistically analyse the individual impacts of ocean circulation and bio

Spatial Dynamics of Wetland Plant Populations: Reponses to Habitat Fragmentation and Land-Use Changes

Fen meadows belong to the few remaining semi-natural plant communities with high species diversity and a high proportion of rare and endangered species. They are influenced by groundwater or aquifer discharge. Their existence depends on continued but low-intensity agricultural use, i.e. lat-season mowing or extensive grazing. Agricultural practices in the past have led to a demise and fragmentation of fen areas. Even though protected by law the persistence of the remaining fens is still threatened by intensified farming (drainage, fertilization) or abandonment (cessation of mowing). The goal of this project is to investigate patterns of diversity and to develop conservation strategies. The following questions are asked: How do different agricultural practices, habitat fragmentation and altitude of the fens influence the diversity of mosses, higher plants and insects? Do the same factors also affect the morphology and the population structure of a typical fen plant species? How does productivity influence the vegetation composition and plant species richness of montane fen meadows? How does fertilization affect the competitive ability of selected plant species? Which conservation measures can protect the endangered montane fens? For the study we randomly selected 36 montane fens from the wetland inventory of Switzerland. For three altitude classes (800-1000 meters above sea level, 1000-1200 meters a.s.l. and 1200-1400 meters a.s.l.) 12 fens each were selected for our investigation, six of them mown once a year, six grazed by cattle's. Species diversity and -composition, vegetation structure, productivity and the population structure of single species were recorded for each of the 36 fens. The influence of nutrient inputs and habitat quality on the competitive ability of fen-species was assessed in a field-experiment. Previous results: Biodiversity of montane fen meadows is mainly influenced by the agricultural practices. Mown sites exhibit more species of vascular plants and butterflies than cattle-grazed areas, whereas grasshoppers prefer grazed sites with complex Vegetation structure. The species richness of vascular plants is closely related to the aboveground biomass. Highest diversity occurs at intermediate levels of bio-mass. High soil fertility reduces species richness. The diversity of mobile organisms such as butterflies not only depends on the habitat quality of the fen sites but additionally on that of the adjacent areas. Habitat fragmentation clearly reduces the diversity of all investigated organisms. In conclusion, only a diverse land-use can maintain the species diversity of different groups of organisms. Additionally, the remaining fen meadows have to be protected from fragmentation and nutrient influx.

Nachhaltige Ernährungssicherheit und Waldnutzung für dürregefährdete, kleinbäuerliche Regionen im Klimawandel in SADC-Ländern, Teilprojekt 2: Landmanagement-Maßnahmen in 'Conservation Agriculture' (CA)

Species level size-normalised weight data for at depth analysis

This dataset contains a compilation of published and new SNW data with corresponding environmental data extracted from CMIP6 that are used in the at depth species level Bayesian regression modelling. Environmental data for G. truncatulinoides comes from 200m depth, all other environmental data is from the sea surface (≤ 20 m).

Group level size-normalised weight data

This dataset contains a compilation of published and new SNW data with corresponding sea surface (≤ 20 m) environmental data extracted from CMIP6 that are used in the group level Bayesian regression modelling.

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