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Stillgewässer

Lage und Bezeichnung der Stillgewässer im Herner Stadtgebiet

Congestion-clearing payments to passengers

This paper reports on a project that considers whether the goals of (de)congestion pricing could be achieved in whole or in part by incentivizing mode-shift rather than using charging to force it: buying rather than selling decongestion. The project developed a method for estimating the net present value of the costs and benefits of a permanent ITS-enabled program of paying people to travel as passengers rather than as drivers - to reduce existing congestion in a target corridor to a target maximum level of delay - taking into account the mix of the traffic and the potential impact of latent demand and induced trips. This is relevant for making better use of existing infrastructure (a "build nothing" alternative to expansion, but not a "do nothing" one), for decarbonizing transport, and in the run up to automated vehicles where the possibility exists that new infrastructure investments in the 1-20-year timeframe will become stranded assets under some future scenarios. The project incorporated: a thorough review of the literature; focus groups; and a survey in a case study corridor in California to test the theory, develop the method, and determine the likely costs and benefits. The main insights include 1) the significance of an ââą Ìintra-peak demand shiftââą Ì that would occur if congestion was removed; 2) the need for four major components in a congestion-clearing payments program: a) incentives to switch from driving to being a passenger, b) incentives to travel at less preferred times, c) park and ride/pool facilities near the bottleneck to ease the passenger switch, and d) some limitation on single-occupant vehicle travel in the peak-of-the-peak in order to reserve space for vehicles carrying passengers; and 3) the possible need for different land-use regulations in a successful ââą Ìpayments to passengersââą Ì environment where the amount of traffic might no longer be an obvious constraint for expanding the local economy. The case study benefit cost analysis delivers a benefit cost ratio of 4.5 to 1. © 2020 The Author(s)

Soil N dynamics as affected by different land use in Western and Southern China

Das Projekt "Soil N dynamics as affected by different land use in Western and Southern China" wird vom Umweltbundesamt gefördert und von Technische Universität Dresden, Institut für Bodenkunde und Standortslehre durchgeführt. The aim of the research project is to quantify the stocks and turnover of soil nitrogen in Western and Southern China as dependent from soil structure and land use. Key soil characteristics are determined at representative sites with regional specific land use and degradation status. The investigations will follow a land use gradient of natural forests, arable and pasture soils, the latter ones considering different degradation and rehabilitation status. The actual and potential soil nitrogen turnover will be horizon-wise quantified and related to soil structure and land use impacts. Beside mineral nitrogen, also preliminary organic N compounds using physical and chemical extraction will be detected. Parameters for the investigations are, beside total C and N stocks and distribution, gross and net N mineralization, nitrification, microbial biomass C and N and microbial respiration and indicators for soil N turnover like active N pools and light fraction of organic matter. In the last phase the structure of the soil microbial microbial community will be determined and related to indicators of nitrogen status and efficiency. The research activities will be carried out in close co-operation with the Institute for Soil and Water Conservation/ Yangling University at loess soils and the Nanjing Institute for Soil Science/ Chinese Academy for Science in Nanjing at red soil sites.

Shift in the syncronisation of leaf decay processes in fragmented streams

Das Projekt "Shift in the syncronisation of leaf decay processes in fragmented streams" wird vom Umweltbundesamt gefördert und von Technische Universität Cottbus, Institut für Boden, Wasser, Luft, Lehrstuhl für Gewässerschutz, Forschungsstelle Bad Saarow durchgeführt. Climate change will increase summer droughts and cause both, premature leaf fall and temporary fragmentation of streams into a series of pools. This match of low flow situations with litter input is likely to alter litter processing. Based on results from Aquashift period 1, we hypothesise change of the invertebrate shredder community and shift among microbial and invertebrate leaf processing. These will change the dynamics of the energy supply of the benthic food web. In pools of summer-dry streams we will expose litter-bags (Alnus glutinosa (L.) Gaertn.) to assess mass loss, microbial colonisation (fungi, bacteria) and invertebrate shredding of leaves. Stepwise exclusion of larger invertebrates from litter-bags will assess the significance of suggested shift from dominance of large shredder (Gammarus) to small invertebrates (Chironomidae). In microcosm experiments we want to investigate the effect of factor combinations found in fragmented pools on microbial and invertebrate leaf processing. A leaf decay simulation model will be build in joint activity with the University Braunschweig to test significance of environmental factors. Linking the population dynamics model of Gammarus pulex at Univ. Braunschweig, the dynamics of FPOM production from leaves will be predicted under various climate change scenarios.

Untersuchung und Quatifizierung des mikrobiellen Abbaus von allochthonem organischen Material durch 'Priming' (MicroPrime)

Das Projekt "Untersuchung und Quatifizierung des mikrobiellen Abbaus von allochthonem organischen Material durch 'Priming' (MicroPrime)" wird vom Umweltbundesamt gefördert und von Forschungsverbund Berlin, Leibniz-Institut für Gewässerökologie und Binnenfischerei durchgeführt. Das Hauptziel dieses Forschungsprojektes ist es, zukünftige Veränderungen im aquatischen Kohlenstoffkreislaufdurch mikrobielle Mechanismen zu charakterisieren, wobei der Priming-Effekt im Vordergrund steht, da er wenig in aquatischen Systemen untersucht ist. In Abhängigkeit der Umweltbedingungen kann Priming den mikrobiellen C-Kreislauf stimulieren oder inhibieren. Daher wollen wir zukünftige Veränderungen in der Rolle von Priming mittels Komponenten-spezifischer Isotopenanalyse (13C/12C von mikrobiellen Phospholipid-Fettsäuren (PFLA)) im Labor und Feld untersuchen. Dafür wollen wir geeignete Protokolle entwickeln, die PFLA Analyse mit molekularen Methoden, z.B. stabile isotope probing -vor allem von Bakterien und Pilzen- miteinander verbinden. Das Ziel ist es, den Einfluss von terrestrischen OC Einträgen auf Priming Effekte zu untersuchen und daher Veränderungen der aquatisch-terrestrischen Kopplung sowie die Rolle globaler Veränderungen für den aquatischen Kohlenstoffkreislauf zu beleuchten. Nach unserem Wissen wird dies die erste Studie sein, die den metabolischen Transfer von labilen und refraktären 13C-markierten OC Pools in einem Ansatz untersucht und es damit ermöglicht, die zugrunde liegenden mikrobiellen Mechanismen des Primings in aquatischen Systemen zu untersuchen. Beide C Pools werden mit unterschiedlicher Pulsierung und Nährstoffkonzentrationen zugegeben, um Effekte der Verfügbarkeit von labilem OM auf Abbauprozesse des refraktären OM zu untersuchen. In der ersten Phase wollen wir Laborexperimente mit definierten Mikroorganismen, deren Fähigkeiten bestimmte Substrate abzubauen bekannt sind, durchführen. Dies erlaubt gezielte Studien zu grundlegenden Mechanismen und Interaktionen von Organismen sowie deren Bedeutung für den OM Abbau. Ein besonderes Augenmerk soll auf die Rolle von aquatischen Pilzen für den Mineralisationsprozess gelegt werden. Zuerst wollen wir die grundlegenden Prozesse des Primings und Synergien zwischen Bakterien und Pilzen untersuchen, um zu quantifizieren, welche OM Pools (labil vs. refraktär) respiriert oder in die mikrobielle Biomasse eingebaut werden. In der zweiten Phase soll die Rolle der charakterisierten Prozesse sowie Interaktionen für den OM-Umsatz für natürliche, komplexe Mikrobengemeinschaften bei unterschiedlichen C-Zugabe Regimes (Simulierung des zukünftigen Anstiegs des C-Eintrages) und unterschiedlicher Nährstoffkonzentrationen (elemental stoichiometry) untersucht werden. In einer dritten Phase sollen diese Studien auf das Freiland mit einer sehr viel höheren Komplexität übertragen werden. Dafür sollen Mesokosmosversuche (http://seelabor.de) durchgeführt werden, wobei vor allem Partikelfluss und Gasflüsse als Ökosystemfunktionen im Vordergrund stehen sollen. Unser modularer Ansatz erlaubt es uns, die Rolle des Priming im C-Kreislauf in der Wassersäule und an aquatisch-terrestrischen Grenzzonen zu quantifizieren und damit die Abschätzung der C-Budgets aquatischer Systeme zu verbessern.

Spatially Explicit Evolution of Diversity (SPEED)

Das Projekt "Spatially Explicit Evolution of Diversity (SPEED)" wird vom Umweltbundesamt gefördert und von Eidgenössische Forschungsanstalt für Wald, Schnee und Landschaft durchgeführt. Background The species environmental niche consists of the biotic and abiotic conditions necessary for long-term persistence. This concept occupies a central place in the ecological theories of competition, limiting ecological similarity, and species distribution. The niche is also important in determining how species respond to ongoing climate change. Species with narrow niches occur in the few geographic locations that offer acceptable conditions. When these species have limited capacity for dispersal, and/or have been isolated by human activity, climate change may force upon species the alternatives of rapid adaptation (via response to natural selection) or extinction. We focus on the niches of species in the Restionaceae, largely endemic to South Africa. The Goals We seek to understand how the species niche has evolved and how the capacity for niche change might impact future patterns of species diversity in the face of ongoing climate change. Gaining an understanding of these niche dynamics entails understanding how species niches differ currently and how these differences evolved. We need to understand how rates of evolution in groups of related species change in time. To understand how niche evolution translates into changes in biodiversity, we need to understand how ecological similarities among species, represented by species evolutionary relationships, influence the composition of ecological communities. The Approach We combine the approaches of evolutionary theory, molecular systematics, and ecology. The approach is interdisciplinary in that activities in these areas produce results that are used to support subsequent activities in other disciplines. Notably, DNA sequence data provide the raw material for developing hypotheses of evolutionary relationships. Data on species occurrences and climate allow us to model the species niche. We combine information on evolutionary relationships, ecological characteristics, and species composition in communities to determine how evolutionary relationships influence the assembly of communities. The Significance of the Project This project develops a framework for evaluating how rapid evolution might contribute to species responses to climate change. With this framework it will be possible to evaluate the potential for evolutionary response to climate change in large groups, potentially hundreds, of related species. We will develop more informed projections of the impacts of ongoing climate change by combining ecological data, understanding of evolutionary relationships and rates, and projections of future climates.

Teil Fauna

Das Projekt "Teil Fauna" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Fakultät II Biologie, Institut für Zoologie durchgeführt. Steinbrueche, wie auch andere Abgrabungen, wurden frueher nur als haessliche Wunden in der Landschaft betrachtet, die schnellstmoeglich wieder rekultiviert werden muessten. Nur langsam setzte sich die Erkenntnis durch, dass sich in ihnen aus der Sicht des Naturschutzes wertvolle Lebensraeume entwickeln koennen. Diesbezueglich wurde in Zusammenarbeit mit Vegetationskundlern untersucht, unter welchen Bedingungen sich Flaechen in aktiven und stillgelegten Steinbrueche in den Raeumen Ulm und Stuttgart zu wertvollen Biotopen entwickeln und wie sich gaengige Rekultivierungsmassnahmen auf die Entwicklung derartiger Flaechen auswirken. Es zeigte sich dass lange Zeit sich selbst ueberlassene Flaechen Tier- und Pflanzenarten beherbergen, die haeufig selten und fuer schuetzenswuerdige Halbtrockenrasen typisch sind, waehrend sich auf rekultivierten Flaechen ueberwiegend weitverbreitete und anspruchslose Arten ansiedelten. Ausserdem boten die nicht rekultivierten Bereiche mit ihren kleinen Tuempeln auch zahlreichen Amphibien- und Libellenarten, die sonst im weiteren Agrar-Umland kaum mehr vorhanden sind, einen Lebensraum. Eine alternative Methode zur Rekultivierung stellt die Ausbringung von Maehgut von schuetzenswerten Flaechen auf kahle Steinbruchbereiche dar. Diese Massnahme wurde auf Versuchsflaechen getestet und erbrachte schon innerhalb der zwei Beobachtungsjahre eine hoechst interessante Entwicklung in Richtung auf schuetzenswerte Flaechen. Aufbauend auf diesen Ergebnissen wurden Managementempfehlungen fuer die 'Folgenutzung Naturschutz' auf Steinbruchflaechen gegeben.

Sub project: Lake Van, Turkey - Pre-Site Survey for a potential new ICDP site

Das Projekt "Sub project: Lake Van, Turkey - Pre-Site Survey for a potential new ICDP site" wird vom Umweltbundesamt gefördert und von Universität Bonn, Institut für Geowissenschaften, Abteilung Paläontologie durchgeführt. Lake Van (eastern Anatolia in Turkey) has a surface area of 3,522 km2, a volume of 576 km3 and a maximum depth of 450 m. It measures 130 km WSW-ENE and is the fourth largest of all terminal lakes in the world. Previous scientific work has shown that annually laminated sediments exist in Lake Van. However, caused by the limitation in drilling equipment available it was only possible to reach a sediment depth less than 10 m covering the Late Glacial and Holocene (last 15,000 years). It would be important to obtain older sediments, at least from the last interglacial-glacial cycle including the Eemian interglacial, or even older cycles. Caused by the dimension of Lake Van, it is only possible to make further progress by focussing national and international experience and expertise under the umbrella of ICDP. During the final European Lake Drilling Project (ELDP) meeting 2001 it was suggested to start with a proposal development for large lake drilling with the ICDP equipment pool GLAD800. In this respect the experience of the drilling projects of lakes Titicaca and Malavi should be used. The applicant was asked to promote and to co-ordinate the first steps of the pre-site survey and to acquire national funds (travel expenses for the first year).

SP 1.1 A combined BaPS-13C stable isotope technique to study the interaction between C and N turnover in alkaline agricultural soils of the North China Plain

Das Projekt "SP 1.1 A combined BaPS-13C stable isotope technique to study the interaction between C and N turnover in alkaline agricultural soils of the North China Plain" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Bodenkunde und Standortslehre, Fachgebiet Biogeophysik durchgeführt. In the intensively managed double-cropping production system of the North China Plain, the excessive use of nitrogen (N) fertilizer has resulted in adverse environmental impacts such as leaching of nitrate to shallow groundwater or gaseous losses of the greenhouse gas N2O. An understanding of N cycling in soil is essential for deriving sustainable fertilization strategies. Nitrogen transformations in soil are closely linked to the carbon (C) cycle. All heterotrophic decomposing micro organism simultaneously assimilate C and N during decomposing plant residues or soil organic matter. An understanding of this linkage is important, for example, for assessing the feedback of a changed N fertilization practice on the soil organic matter pool. To study and quantify the C and N fluxes in soil, we need a set of reliable and accurate methods. During the last decade a novel method, the Barometric Process Separation, has been used to measure gross nitrification rates in soil. Recently, it has been shown that the use of the BaPS method becomes problematic at soil pH greater than 6. At pH values above 6 the BaPS calculation is strongly affected by the CO2,aq term, i.e. the dissolution of gaseous CO2 during incubation. So far, no methods are available to accurately quantifying this term. In our study, we aim at developing a novel combined Barometric Process Separation (BaPS)-13C stable isotope technique, which allows an accurate quantification of the CO2,aq term. In parallel, we will study to which extent the incorporation of plant residues of different quality immobilises surplus soil nitrate and its potential to reduce nitrate leaching in soils with a nitrate-dominated mineral N pool. Moreover, we will study the mid- and short term interaction of C and N turnover at the process-level to get a better understanding on the feedback mechanism between both matter cycles.

INI 1128575 STP-2: Fate of Plant Residues in Soil Organic Matter Pools under Contrast Land Use as Evaluated by Two Tracer Techniques

Das Projekt "INI 1128575 STP-2: Fate of Plant Residues in Soil Organic Matter Pools under Contrast Land Use as Evaluated by Two Tracer Techniques" wird vom Umweltbundesamt gefördert und von Universität Bayreuth, Fachgruppe Geowissenschaften, Bayreuther Zentrum für Ökologie und Umweltforschung (BayCEER), Lehrstuhl für Agrarökosystemforschung durchgeführt. Soil C sequestration through changes in land use and management is one of the important strategies to mitigate the global greenhouse effect. Plant residue is the primary source of C formation and sequestration in soil. The relative contribution of residues depends upon composition and decomposability of litter which is a function of lad use and management. The present project is conceived with objective to evaluate the fate of plant residue in soil C influenced by different land-use management practices. Ultimate aim to sketch policy for appropriate management practices, which would facilitate enrichment of C stock in soils for maintaining soil health and fertility as well as mitigation of global warming by C sequestration. Management practices like intensity of tilling and no tillage have a definite effect on SOC stock; it would be considered as pertinent management practice for residue derived C-turnover. To fulfil the objective as stated, representative soil samples will be collected under various land covers/uses and management practices and analysed for important physico chemical properties e.g. pH, CEC, clay content, bulk density, soil water storage, and soil porosity are the important soil physical parameters which influences C load in soil. Different pools of C viz. total SOC (Ctot), Water stable aggregates, labile fractions of oxidisable organic carbon etc. will be studied to know the C stock and its distribution in soil. Impact of added plant residue on C sequestration and C dynamics of plant residues decomposition in contrast land use will be analyzed and quantified by using 14C labelled plant residues as well as 13C natural abundance and allow for differentiation between residues-derived carbon and native SOC. Labeled microbial biomass C and mineralizable C, acetone exactable reside, 14C and d13C in CO2 and in SOM pool will be measured that may provide precise estimates of residues decomposition rates and contribution in soil organic C. Microbial biomass carbon (Cmic) and mineralizable carbon (Cmin) measured as early indicators of future trends in total SOM as it provides a good measure of labile organic matter because it directly reflects recent soil organic matter turnover. Data on biomass productivity will also be collected from those sites. Results would help us to know the relative efficiency of different land use managements for organic C enrichment or depletion in soils.

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