02755nas a2200169 4500008004100000022001300041245010700054210006900161260001600230300001200246490000800258520218000266100002802446700002002474700002402494856006702518 2018 eng d a0304380000aIntermediate foraging large herbivores maintain semi-open habitats in wilderness landscape simulations0 aIntermediate foraging large herbivores maintain semiopen habitat cJan-07-2018 a10 - 210 v3793 a
In the context of the rewilding Europe debate, the German national strategy on biodiversity aims to dedicate two percent of the German state area to wilderness development until 2020. Many of these potential large wilderness reserves harbor open habitats that require protection according to the Flora-Fauna-Habitat-directive of the European Union. As forests prevail in potential natural vegetation, research is required, to which extent wild large herbivores and natural disturbances may create semi-open landscape patterns in the long-term. We used the spatially explicit process-based model of pasture-woodland ecosystem dynamics WoodPaM, to analyze the long-term interactions between intermediate foraging large wild herbivores and vegetation dynamics in edaphically heterogeneous forest-grassland mosaic landscapes. We newly implemented a routine for intermediate foraging herbivores. We determined herbivore impact on vegetation from the quantitative balance between the demand and supply of herbaceous forage and woody browse. In abstract landscapes that represent the conditions in the established German wilderness area "Döberitzer Heide", we simulated potential future landscape dynamics on open land, in forest and along forest edges with and without intermediate foraging large herbivores and for a climate change scenario. In our simulations the currently open landscape was conserved and even more the opening of current oak and beech forest was promoted. Canopy thinning and patch-mosaics of oak, birch, poplar and pine stands increased the overall nature conservation value in the long-term. To the contrary, open habitats were lost in simulations without herbivores. Moreover, our simulations suggested that intermediate foraging herbivores are especially suitable to maintain semi-open landscapes in wilderness areas, because (i) no additional winter forage was required, the natural availability of browse was sufficient. (ii) Their grazing maintained open land and their browsing thinned tree canopies even on poor sites that were unattractive for foraging. Here, habitat was maintained for threatened species from dry grasslands.
1 aSchulze, Kiowa, Alraune1 aRosenthal, Gert1 aPeringer, Alexander uhttps://linkinghub.elsevier.com/retrieve/pii/S030438001830113301701nas a2200169 4500008004100000022001300041245008100054210006900135260001600204300001400220490000700234520098900241100002301230700002201253700002301275856023301298 2017 eng d a1364815200aAn integrated model to evaluate water-energy-food nexus at a household scale0 aintegrated model to evaluate waterenergyfood nexus at a househol cJan-07-2017 a366 - 3800 v933 aTo achieve a sustainable supply and effectively manage water, energy and food (WEF) demand, interactions between WEF need to be understood. This study developed an integrated model, capturing the interactions between WEF at end-use level at a household scale. The model is based on a survey of 419 households conducted to investigate WEF over winter and summer for the city of Duhok, Iraq. A bottom-up approach was used to develop this system dynamics-based model. The model estimates WEF demand and the generated organic waste and wastewater quantities. It also investigates the impact of change in user behaviour, diet, income, family size and climate.
The simulation results show a good agreement with the historical data. Using the model, the impact of Global Scenario Group (GSG) scenarios was investigated. The results suggest that the ‘fortress world’ scenario (an authoritarian response to the threat of breakdown) had the highest impact on WEF.
1 aHussien, Wa'el, A.1 aMemon, Fayyaz, A.1 aSavić, Dragan, A. uhttps://linkinghub.elsevier.com/retrieve/pii/S1364815216306594https://api.elsevier.com/content/article/PII:S1364815216306594?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S1364815216306594?httpAccept=text/plain00835nas a2200241 4500008004100000245009200041210006900133260001600202490000600218100001600224700002100240700001800261700001500279700001800294700001500312700001400327700001600341700001900357700001500376700001400391700001500405856017300420 2016 eng d00aIntermediate tree cover can maximize groundwater recharge in the seasonally dry tropics0 aIntermediate tree cover can maximize groundwater recharge in the cJan-04-20160 v61 aIlstedt, U.1 aTobella, Bargu?s1 aBazi?, H., R.1 aBayala, J.1 aVerbeeten, E.1 aNyberg, G.1 aSanou, J.1 aBenegas, L.1 aMurdiyarso, D.1 aLaudon, H.1 aSheil, D.1 aMalmer, A. uhttp://www.nature.com/articles/srep21930http://www.nature.com/articles/srep21930.pdfhttp://www.nature.com/articles/srep21930.pdfhttp://www.nature.com/articles/srep2193000675nas a2200169 4500008003900000022001300039245014100052210006900193260001200262300001400274490000800288100002200296700002100318700002000339700001900359856012700378 2015 d a0025326X00aInforming Marine Spatial Planning (MSP) with numerical modelling: A case-study on shellfish aquaculture in Malpeque Bay (Eastern Canada)0 aInforming Marine Spatial Planning MSP with numerical modelling A c11/2015 a200 - 2160 v1001 aFilgueira, Ramón1 aGuyondet, Thomas1 aBacher, Cédric1 aComeau, Luc, A u//www.simulistics.com/publications/informing-marine-spatial-planning-msp-numerical-modelling-case-study-shellfish-aquacult02509nas a2200145 4500008003900000245012100039210006900160300001400229490000700243520199900250100002202249700001502271700002002286856005702306 2014 d00aImplementation of marine spatial planning in shellfish aquaculture management: modeling studies in a Norwegian fjord0 aImplementation of marine spatial planning in shellfish aquacultu a832–8430 v243 aShellfish carrying capacity is determined by the interaction of a cultured species with its ecosystem, which is strongly influenced by hydrodynamics. Water circulation controls the exchange of matter between farms and the adjacent areas, which in turn establishes the nutrient supply that supports phytoplankton populations. The complexity of water circulation makes necessary the use of hydrodynamic models with detailed spatial resolution in carrying capacity estimations. This detailed spatial resolution also allows for the study of processes that depend on specific spatial arrangements, e.g., the most suitable location to place farms, which is crucial for marine spatial planning, and consequently for decision support systems. In the present study, a fully spatial physical-biogeochemical model has been combined with scenario building and optimization techniques as a proof of concept of the use of ecosystem modeling as an objective tool to inform marine spatial planning. The object of this exercise was to generate objective knowledge based on an ecosystem approach to establish new mussel aquaculture areas in a Norwegian fjord. Scenario building was used to determine the best location of a pump that can be used to bring nutrient-rich deep waters to the euphotic layer, increasing primary production, and consequently, carrying capacity for mussel cultivation. In addition, an optimization tool, parameter estimation (PEST), was applied to the optimal location and mussel standing stock biomass that maximize production, according to a preestablished carrying capacity criterion. Optimization tools allow us to make rational and transparent decisions to solve a well-defined question, decisions that are essential for policy makers. The outcomes of combining ecosystem models with scenario building and optimization facilitate planning based on an ecosystem approach, highlighting the capabilities of ecosystem modeling as a tool for marine spatial planning.1 aFilgueira, Ramón1 aGrant, Jon1 aStrand, Øivind uhttp://www.esajournals.org/doi/pdf/10.1890/13-0479.102003nas a2200253 4500008003900000245009500039210006900134260001200203300001400215490000700229520119300236653005301429653001501482653001101497653001901508653001501527653002601542653001101568653001101579653001801590100001501608700001501623856011101638 2005 d00a“It was an artefact not the result”: A note on systems dynamic model development tools0 aIt was an artefact not the result A note on systems dynamic mode c12/2005 a1543-15480 v203 aEnvironmental modelling is done more and more by practising ecologists rather than computer scientists or mathematicians. This is because there is a broad spectrum of development tools available that allows graphical coding of complex models of dynamic systems and help to abstract from the mathematical issues of the modelled system and the related numerical problems for estimating solutions. In this contribution, we study how different modelling tools treat a test system, a highly non-linear predator–prey model, and how the numerical solutions vary. We can show that solutions (a) differ if different development tools are chosen but the same numerical procedure is selected; (b) depend on undocumented implementation details; (c) vary even for the same tool but for different versions; and (d) are generated but with no notifications on numerical problems even if these could be identified. We conclude that improved documentation of numeric methods used in the modelling software is essential to make sure that process based models formulated in terms of these modelling packages do not become “black box” models due to uncertainty in integration methods.
10aLotka-Volterra equation; Predator-prey modelling10aMATEMATICA10aMATLAB10aModel analysis10aMODELMAKER10aNumerical ODE solvers10aSimile10aSTELLA10aStiff systems1 aSeppelt, R1 aRichter, O u//www.simulistics.com/publications/it-was-artefact-not-result-note-systems-dynamic-model-development-tools