00937nas a2200205 4500008004100000022001400041245014800055210006900203260001600272300001600288490000800304100002200312700002200334700002300356700001900379700002200398700002900420700002300449856025900472 2018 eng d a0378-190900aThe effect of environmental conditions on Atlantic salmon smolts’ (Salmo salar) bioenergetic requirements and migration through an inland sea0 aeffect of environmental conditions on Atlantic salmon smolts Sal cJan-10-2018 a1467 - 14820 v1011 aStrople, Leah, C.1 aFilgueira, Ramón1 aHatcher, Bruce, G.1 aDenny, Shelley1 aBordeleau, Xavier1 aWhoriskey, Frederick, G.1 aCrossin, Glenn, T. uhttp://link.springer.com/10.1007/s10641-018-0792-5http://link.springer.com/content/pdf/10.1007/s10641-018-0792-5.pdfhttp://link.springer.com/article/10.1007/s10641-018-0792-5/fulltext.htmlhttp://link.springer.com/content/pdf/10.1007/s10641-018-0792-5.pdf02843nas a2200217 4500008004100000022001300041245010100054210006900155260001600224300001400240490000800254520196400262100001902226700002402245700002602269700002802295700002302323700002002346700002602366856023302392 2018 eng d a0048969700aShifts in wind energy potential following land-use driven vegetation dynamics in complex terrain0 aShifts in wind energy potential following landuse driven vegetat cJan-10-2018 a374 - 3840 v6393 a

Many mountainous regions with high wind energy potential are characterized by multi-scale variabilities of vegetation in both spatial and time dimensions, which strongly affect the spatial distribution of wind resource and its time evolution. To this end, we developed a coupled interdisciplinary modeling framework capable of assessing the shifts in wind energy potential following land-use driven vegetation dynamics in complex mountain terrain. It was applied to a case study area in the Romanian Carpathians. The results show that the overall shifts in wind energy potential following the changes of vegetation pattern due to different land-use policies can be dramatic. This suggests that the planning of wind energy project should be integrated with the land-use planning at a specific site to ensure that the expected energy production of the planned wind farm can be reached over its entire lifetime. Moreover, the changes in the spatial distribution of wind and turbulence under different scenarios of land-use are complex, and they must be taken into account in the micro-siting of wind turbines to maximize wind energy production and minimize fatigue loads (and associated maintenance costs). The proposed new modeling framework offers, for the first time, a powerful tool for assessing long-term variability in local wind energy potential that emerges from land-use change driven vegetation dynamics over complex terrain. Following a previously unexplored pathway of cause-effect relationships, it demonstrates a new linkage of agro- and forest policies in landscape development with an ultimate trade-off between renewable energy production and biodiversity targets. Moreover, it can be extended to study the potential effects of micro-climatic changes associated with wind farms on vegetation development (growth and patterning), which could in turn have a long-term feedback effect on wind resource distribution in mountainous regions.

1 aFang, Jiannong1 aPeringer, Alexander1 aStupariu, Mihai-Sorin1 aPătru-Stupariu, Ileana1 aButtler, Alexandre1 aGolay, Francois1 aPorté-Agel, Fernando uhttps://linkinghub.elsevier.com/retrieve/pii/S0048969718317182https://api.elsevier.com/content/article/PII:S0048969718317182?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S0048969718317182?httpAccept=text/plain02835nas a2200217 4500008004100000022001300041245010400054210006900158260001600227300001400243490000800257520195300265100002402218700002302242700002202265700002802287700002302315700002602338700002002364856023302384 2017 eng d a0304380000aDisturbance-grazer-vegetation interactions maintain habitat diversity in mountain pasture-woodlands0 aDisturbancegrazervegetation interactions maintain habitat divers cJan-09-2017 a301 - 3100 v3593 a

Low-intensity livestock grazing is a widespread management tool in order to maintain habitat diversity in mountain pasture-woodlands for nature conservation purposes. Historical photographs indicate that forest disturbance significantly contributed to forest-grassland mosaic pattern formation. Disturbance-grazer interactions are however poorly understood and the effects of logging or windthrow are rarely considered in management plans. Moreover, disturbance-grazer interactions are crucial for the maintenance of open habitats in the upcoming “rewilding” approach of nature conservation. We aimed to understand the effects of forest gap creation by the breakdown of senile trees or by single-tree cutting and of large forest openings by windthrow or logging on mosaic pattern formation in pasture-woodlands that were grazed by cattle and dominated by tree species with distinct regeneration ecology (Picea abies vs. Fagus sylvatica). We used the process-based model of pasture-woodland vegetation dynamics WoodPaM and newly implemented a forest disturbance routine. We simulated disturbance and grazing scenarios in an artificial mountain landscape and analyzed mosaic patterns with landscape metrics. We found that grazing in absence of disturbance promoted simply structured mosaics that were preconditioned by topography. Only large-scale forest disturbance disrupted this pattern and maintained the historical heterogeneous distribution of grassland communities across all habitat conditions (especially species-rich mountain grasslands on poor soil). This prerequisite is stronger in pasture-woodlands where the ecology of the dominant tree species promotes forest-grassland segregation (F. sylvatica in our case) and less in naturally thin-canopy mountain forest close to the tree line (P. abies). In wilderness areas, the very low density of grazers may limit the maintenance of open habitats regardless disturbance.

1 aPeringer, Alexander1 aButtler, Alexandre1 aGillet, François1 aPătru-Stupariu, Ileana1 aSchulze, Kiowa, A.1 aStupariu, Mihai-Sorin1 aRosenthal, Gert uhttps://linkinghub.elsevier.com/retrieve/pii/S030438001730100Xhttps://api.elsevier.com/content/article/PII:S030438001730100X?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S030438001730100X?httpAccept=text/plain01967nas a2200169 4500008004100000022001300041245007200054210006900126260001600195300001200211490000700223520128000230100001901510700001901529700001601548856023301564 2017 eng d a1364815200aModular and spatially explicit: A novel approach to system dynamics0 aModular and spatially explicit A novel approach to system dynami cJan-08-2017 a48 - 620 v943 a

The Open Modeling Environment (OME) is an open-source System Dynamics (SD) simulation engine which has been created as a joint project between Oregon State University and the US Environmental Protection Agency. It is designed around a modular implementation, and provides a standardized interface for interacting with spatially explicit data while still supporting the standard SD model components. OME can be run as a standalone simulation or as a plugin to a larger simulation framework, and is capable of importing Models from several SD model formats, including Simile model files, Vensim model files, and the XMILE interchange format. While it has been released, OME is still under development, and a number of potential future improvements are discussed. To help illustrate the utility of OME, an example model design process is provided as an Appendix.

1 aWingo, Patrick1 aBrookes, Allen1 aBolte, John uhttps://linkinghub.elsevier.com/retrieve/pii/S1364815216308453https://api.elsevier.com/content/article/PII:S1364815216308453?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S1364815216308453?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/srep2193002521nas a2200217 4500008004100000022001300041245013700054210006900191260001600260300001200276490000800288520177600296100002402072700002202096700002002118700002102138700002802159700002602187700002302213856006702236 2016 eng d a0304380000aLandscape-scale simulation experiments test Romanian and Swiss management guidelines for mountain pasture-woodland habitat diversity0 aLandscapescale simulation experiments test Romanian and Swiss ma cJan-06-2016 a41 - 490 v3303 a

Distinct guidelines have been proposed in Romania and Switzerland for the management of pasture-woodlands that either focused on the regulation of grazing pressure (Romanian production perspective) or overall tree cover (Swiss conservation perspective). However, the landscape structural diversity and the cover of forest-grassland ecotones, which are both crucial for nature conservation value, were not explicitly considered.

We aimed to compare the country-specific management guidelines regarding their efficiency for the conservation of the structurally diverse forest-grassland mosaics in the light of recent land-use and climate change.

In strategic simulation experiments using the process-based model of pasture-woodland ecosystems WoodPaM, we analyzed the relationships among drivers for the formation of mosaic patterns (grazing intensity, climate change) and the resulting landscape properties (tree cover, forest-grassland ecotones, mosaic structure) during the past until today (2000 AD).

The results showed that tree canopy densification following recent climate warming is likely to trigger landscape structural shifts. Medium grazing pressure promoted the development of the full range of pasture-woodland habitats and is therefore confirmed as a management strategy that balances agronomic demands and nature conservation value. Tree cover is rejected as a criteria to monitor pasture-woodland conservation status, because its relationship to landscape structural diversity and to the cover of forest-grassland ecotones did not hold for changing climate.

Our results suggest “experimental-retrospective” analysis as a useful tool to test conclusions from expert knowledge.

1 aPeringer, Alexander1 aGillet, François1 aRosenthal, Gert1 aStoicescu, Ioana1 aPătru-Stupariu, Ileana1 aStupariu, Mihai-Sorin1 aButtler, Alexandre uhttps://linkinghub.elsevier.com/retrieve/pii/S030438001630079501250nas a2200217 4500008004100000022001400041245013200055210006900187260001600256300001400272490000700286520052500293100002400818700002300842700002100865700002600886700002000912700002300932700002200955856005500977 2016 eng d a0921-297300aMulti-scale feedbacks between tree regeneration traits and herbivore behavior explain the structure of pasture-woodland mosaics0 aMultiscale feedbacks between tree regeneration traits and herbiv cJan-05-2016 a913 - 9270 v313 a

The pasture-woodlands of Central Europe are low-intensity grazing systems in which the structural richness of dynamic forest-grassland mosaics is causal for their high biodiversity. Distinct mosaic patterns in Picea abies- and Fagus sylvatica-dominated pasture-woodlands in the Swiss Jura Mountains suggest a strong influence of tree species regeneration ecology on landscape structural properties. At the landscape scale, however, cause-effect relationships are complicated by habitat selectivity of livestock.

1 aPeringer, Alexander1 aSchulze, Kiowa, A.1 aStupariu, Ileana1 aStupariu, Mihai-Sorin1 aRosenthal, Gert1 aButtler, Alexandre1 aGillet, François uhttp://link.springer.com/10.1007/s10980-015-0308-z00675nas 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-aquacult02003nas a2200181 4500008003900000022001300039245013200052210006900184260001200253300001200265490000700277520134100284100002001625700001501645700001701660700001701677856012701694 2015 d a2212041600aThe Multiscale Integrated Model of Ecosystem Services (MIMES): Simulating the interactions of coupled human and natural systems0 aMultiscale Integrated Model of Ecosystem Services MIMES Simulati c04/2015 a30 - 410 v123 aIn coupled human and natural systems ecosystem services form the link between ecosystem function and what humans want and need from their surroundings. Interactions between natural and human components are bidirectional and define the dynamics of the total system. Here we describe the MIMES, an analytical framework designed to assess the dynamics associated with ecosystem service function and human activities. MIMES integrate diverse types of knowledge and elucidate how benefits from ecosystem services are gained and lost. In MIMES, users formalize how materials are transformed between natural, human, built, and social capitals. This information is synthesized within a systems model to forecast ecosystem services and human-use dynamics under alternative scenarios. The MIMES requires that multiple ecological and human dynamics be specified, and that outputs may be understood through different temporal and spatial lenses to assess the effects of different actions in the short and long term and at different spatial scales. Here we describe how MIMES methodologies were developed in association with three case studies: a global application, a watershed model, and a marine application. We discuss the advantages and disadvantage of the MIMES approach and compare it to other broadly used ecosystem service assessment tools.1 aBoumans, Roelof1 aRoman, Joe1 aAltman, Irit1 aKaufman, Les u//www.simulistics.com/publications/multiscale-integrated-model-ecosystem-services-mimes-simulating-interactions-coupled-hu01946nas a2200157 4500008003900000245011100039210006900150300001200219490000600231520143500237100001701672700001301689700001401702700001501716856005701731 2013 d00aEcosystem modelling for ecosystem-based management of bivalve aquaculture sites in data‑poor environment0 aEcosystem modelling for ecosystembased management of bivalve aqu a117-1330 v43 aAlthough models of carrying capacity have been around for some time, their use in aquaculture management has been limited. This is partially due to the cost involved in generating and testing the models. However, the use of more generic and flexible models could facilitate the implementation of modelling in management. We have built a generic core for coupling biogeochemical and hydrodynamic models using Simile (www.simulistics.com), a visual simulation environment software that is well-suited to accommodate fully spatial models. Specifically, Simile integrates PEST (model-independent parameter estimation, Watermark Numerical Computing, www.pesthomepage.org), an optimization tool that uses the Gauss-Marquardt-Levenberg algorithm and can be used to estimate the value of a parameter, or set of parameters, in order to minimize the discrepancies between the model results and a dataset chosen by the user. The other critical aspect of modelling exercises is the large amount of data necessary to set up, tune and groundtruth the ecosystem model. However, ecoinformatics and improvements in remote sensing procedures have facilitated acquisition of these datasets, even in data-poor environments. In this paper we describe the required datasets and stages of model development necessary to build a biogeochemical model that can be used as a decision-making tool for bivalve aquaculture management in data-poor environments.1 aFilgueira, R1 aGrant, J1 aStuart, R1 aBrown, M S uhttp://www.int-res.com/abstracts/aei/v4/n2/p117-133/00507nas a2200145 4500008003900000245008700039210007100126300001000197490000600207100002200213700001500235700002000250700002000270856007100290 2012 d00aA physical–biogeochemical coupling scheme for modeling marine coastal ecosystems0 aphysical–biogeochemical coupling scheme for modeling marine coas a71-800 v71 aFilgueira, Ramón1 aGrant, Jon1 aBacher, Cédric1 aCarreau, Michel uhttp://www.sciencedirect.com/science/article/pii/S157495411100097508328nas a2200145 4500008003900000245008900039210006900128260002600197300001000223490000700233520784400240100002008084700002008104856005808124 2009 d00aModeling the soil system: Bridging the gap between pedology and soil–water physics0 aModeling the soil system Bridging the gap between pedology and s bElsevier B.Vc05/2009 a51-610 v673 a

 The biological and geochemical processes in soil such as organic matter mineralization, microbiological activity, and plant alimentation can be accurately assessed and modeled only with the knowledge of the thermodynamic status of the soil medium where these processes take place. However, current soil water models do not define and characterize the soil structure or the thermodynamic state of the soil water interacting with this structure. This article presents a new paradigm in characterizing and previous termmodelingnext term the organized soil medium and the physical properties resulting from this organization. It describes a framework of the previous termmodelingnext term approach as a contribution to the General Systems theory. The basic concept of Representative Elementary Volume (REV) in soil physics and hydrology was transformed into the concept of Structure Representative Volume (SREV) which takes into account the hierarchical organization of the structured soil medium. The pedostructure is defined as the SREV of the soil medium and this concept is at the basis of the new paradigm including variables, equations, parameters, and units in soil physics, in a similar way that the REV is at the basis of the continuous porous media mechanics applied to soils. The paradigm allows for a thermodynamic characterization of the structured soil medium with respect to soil water content then bridging the gap between pedology and soil physics. We show that the two points of view (REV and SREV) are complementary and must be used in the scaling of information. This approach leads to a new dimension in soil–water properties characterization that ensures a physically based previous termmodelingnext term of processes in soil and the transfer of information from the physical scale of processes (pedostructure or laboratory measurements scale) to the application scale of the other disciplines (previous termmodelingnext term and mapping scale).

1 aBraudeaua, Erik1 aMohtar, Rabi, H uhttp://dx.doi.org/10.1016/j.gloplacha.2008.12.002 03051nas a2200133 4500008003900000245008400039210006900123300001400192490000600206520257100212100005802783700001402841856006202855 2009 d00aA multi-scale ''soil water structure'' model based on the pedostructure concept0 amultiscale soil water structure model based on the pedostructure a1111-11630 v63 a

 Current soil water models do not take into account the internal organization of the soil medium and, a fortiori, the physical interaction between the water film surrounding the solid particles of the soil structure, and the surface charges of this structure. In that sense they empirically deal with the physical soil properties that are all generated from this soil water-structure interaction. As a result, the thermodynamic state of the soil water medium, which constitutes the local physical conditions, namely the pedo-climate, for biological and geo-chemical processes in soil, is not defined in these models. The omission of soil structure from soil characterization and modeling does not allow for coupling disciplinary models for these processes with soil water models. This article presents a soil water structure model, Kamel®, which was developed based on a new paradigm in soil physics where the hierarchical soil structure is taken into account allowing for defining its thermodynamic properties. After a review of soil physics principles which forms the basis of the paradigm, we describe the basic relationships and functionality of the model. Kamel® runs with a set of 15 soil input parameters, the pedohydral parameters, which are parameters of the physically-based equations of four soil characteristic curves that can be measured in the laboratory. For cases where some of these parameters are not available, we show how to estimate these parameters from commonly available soil information using published pedotransfer functions. A published field experimental study on the dynamics of the soil moisture profile following a pounded infiltration rainfall event was used as an example to demonstrate soil characterization and Kamel® simulations. The simulated soil moisture profile for a period of 60 days showed very good agreement with experimental field data. Simulations using input data calculated from soil texture and pedotransfer functions were also generated and compared to simulations of the more ideal characterization. The later comparison illustrates how Kamel® can be used and adapt to any case of soil data availability. As physically based model on soil structure, it may be used as a standard reference to evaluate other soil-water models and also pedotransfer functions at a given location or agronomical situation.

1 aBraudeau, Mohtar El Ghezal Crayol Salahat, R H N 1 aMartin, P uhttp://www.hydrol-earth-syst-sci-discuss.net/6/1111/2009/03363nas a2200445 4500008003900000020001800039245010000057210006900157260001400226300001200240490000600252520204200258653005002300653002902350653002202379653002102401653002502422100001702447700001702464700002102481700001602502700002202518700001702540700001802557700001302575700001702588700001602605700001402621700001602635700001402651700001702665700001602682700001502698700001302713700001702726700001602743700001702759700001402776856012702790 2008 d a978008056886700aChapter Seven Integrated Modelling Frameworks for Environmental Assessment and Decision Support0 aChapter Seven Integrated Modelling Frameworks for Environmental  b Elsevier a101-1180 v33 a

In this chapter we investigate the motivation behind the development of modelling frameworks that explicitly target the environmental domain. Despite many commercial and industrial-strength frameworks being available, we claim that there is a definite niche for environmental-specific frameworks. We first introduce a general definition of what is an environmental integrated modelling framework, leading to an outline of the requirements for a generic software architecture for such frameworks. This identifies the need for a knowledge layer to support the modelling layer and an experimentation layer to support the execution of models.

The chapter then focuses on the themes of knowledge representation, model management and model execution. We advocate that appropriate knowledge representation and management tools can facilitate model integration and linking. We stress that a model development process adhering to industry standards and good practices, called “model engineering,” is to be pursued. We focus on the requirements of the experimental frame, which can ensure transparency and traceability in the execution of simulation scenarios and optimisation problems associated with complex integrated assessment studies.

A promising trend for knowledge representation is the use of ontologies that have the capacity to elicit the meaning of knowledge in a manner that is logical, consistent and understandable by computers and the knowledge worker community. This new path in knowledge-based computing will support retention of institutional knowledge, while putting modelling back in the hands of modellers. Environmental modelling will then become a conceptual activity, focusing on model design rather than model implementation, with code generation being delegated to some degree to ontology-aware tools. In this respect, we envision the whole model lifecycle to change drastically, becoming more of a theoretical activity and less of a coding-intensive, highly engineering-oriented task.

10aenvironmental integrated modelling frameworks10aknowledge representation10amodel engineering10amodel management10amodelling frameworks1 aRizzoli, A E1 aLeavesley, G1 aII, Ascough, J C1 aArgent, R M1 aAthanasiadis, I N1 aBrilhante, V1 aClaeys, F H A1 aDavid, O1 aDonatelli, M1 aGijsbers, P1 aHavlik, D1 aKassahun, A1 aKrause, P1 aQuinn, N W T1 aScholten, H1 aSojda, R S1 aVilla, F1 aJakeman, A J1 aVoinov, A A1 aRizzoli, A E1 aChen, S H u//www.simulistics.com/publications/chapter-seven-integrated-modelling-frameworks-environmental-assessment-and-decision-sup00709nas a2200205 4500008003900000245009900039210006900138100002000207700002500227700002500252700002400277700002600301700001800327700002100345700001800366700002200384700002300406700002000429856005400449 2008 d00aCONCEPT MAPS FOR COMBINING HARD AND SOFT SYSTEM THINKING IN THE MANAGEMENT OF SOCIO-ECOSYSTEMS0 aCONCEPT MAPS FOR COMBINING HARD AND SOFT SYSTEM THINKING IN THE 1 aSalerno, Franco1 aCuccillato, Emanuele1 aMuetzelfeldt, Robert1 aGiannino, Francesco1 aBajracharya, Birendra1 aCaroli, Paolo1 aViviano, Gaetano1 aStaiano, Anna1 aFabrizio Cartenì1 aMazzoleni, Stefano1 aTartari, Gianni uhttp://cmc.ihmc.us/cmc2008papers/cmc2008-p190.pdf01479nas a2200121 4500008003900000245007700039210006900116300000700185490000700192520102900199100002201228856010701250 2008 d00aA spatiotemporal model of shifting cultivation and forest cover dynamics0 aspatiotemporal model of shifting cultivation and forest cover dy a280 v133 a

Sustainable use of humid forest resources as a source of fertile land for cultivation requires long periods of fallow and the ability to move the zone of active cultivation from one location to another over time. At the individual field level, shifting cultivation is essentially a resource extraction problem akin to a pulse fishery – a short period of intensive use of the stock of soil fertility followed by a long idle period permitting regeneration. This paper describes a spatiotemporal model of resource extraction adapted to the use of forest resources by shifting cultivators. Theoretically grounded in the spatial and household modelling literature, it is a structural simulation model of household decision-making, and includes a demonstration of the conceptwith a limited data set from southern Cameroon. Use of a stated preference approach to modelling decision-making identifies individual preferences and spatial path-dependency as important sources of shortened fallows and resource degradation.

1 aBrown, Douglas, R u//www.simulistics.com/publications/spatiotemporal-model-shifting-cultivation-and-forest-cover-dynamics02788nas a2200265 4500008003900000245013300039210006900172260001100241300001200252490000800264520188500272653001602157653002202173653002002195653002102215653001202236100001502248700002402263700002402287700002002311700002002331700002602351700001802377856012702395 2007 d00aA box model of carrying capacity for suspended mussel aquaculture in Lagune de la Grande-Entrée, Iles-de-la-Madeleine, Québec 0 abox model of carrying capacity for suspended mussel aquaculture  c1/2007 a193-2060 v2003 a

An object-oriented model of environment–mussel aquaculture interactions and mussel carrying-capacity within Lagune de la Grande-Entrée (GEL), Iles-de-la-Madeleine, Québec, was constructed to assist in development of sustainable mussel culture in this region. A multiple box ecosystem model for GEL tied to the output of a hydrodynamic model was constructed using Simile software, which has inherent ability to represent spatial elements and specify water exchange between modelled regions. Mussel growth and other field data were used for model validation. Plackett–Burman sensitivity analysis demonstrated that a variety of bioenergetic parameters of zooplankton and phytoplankton submodels were important in model outcomes. Model results demonstrated that mussel aquaculture can be further developed throughout the lagoon. At present culture densities, phytoplankton depletion is minimal, and there is little food limitation of mussel growth. Results indicated that increased stocking density of mussels in the existing farm will lead to decreased mass per individual mussel. Depending on the location of new farm emplacement within the lagoon, implementation of new aquaculture sites either reduced mussel growth in the existing farm due to depletion of phytoplankton, or exhibited minimum negative impact on the existing farm. With development throughout GEL, an excess of phytoplankton was observed during the year in all modelled regions, even at stocking densities as high as 20 mussels m−3. Although mussels cultured at this density do not substantially impact the ecosystem, their growth is controlled by the flux of phytoplankton food and abundance of zooplankton competitors. This model provides an effective tool to examine expansion of shellfish farming to new areas, balancing culture location and density.

10aAquaculture10aCarrying-capacity10aEcosystem model10aMagdalen Islands10aMussels1 aGrant, Jon1 aCurran, Kristian, J1 aGuyondet, Thomas, L1 aTita, Guglielmo1 aBacher, Cédric1 aKoutitonsky, Vladimir1 aDowd, Michael u//www.simulistics.com/publications/box-model-carrying-capacity-suspended-mussel-aquaculture-lagune-de-la-grande-entr-e-ile02591nas a2200205 4500008003900000245013100039210006900170260002200239300001200261490000700273520181500280653002402095653002002119653001602139653002502155653002902180653002702209100002202236856012702258 2006 d00aPersonal preferences and intensification of land use: their impact on southern Cameroonian slash-and-burn agroforestry systems0 aPersonal preferences and intensification of land use their impac bSpringerc03/2006 a53–670 v683 a

Where long forest-fallows are no longer practiced, productivity declines in the absence of input substitution, as does the ability of subsistence farmers to earn an adequate livelihood from shifting cultivation. Land availability, population density and productivity-related factors such as soil fertility and labour requirements are not the only factors that affect fallow length and land use intensification in shifting cultivation agroforestry systems. Households surveyed indicated that various other decision criteria (e.g., proximity to other fields and the protection of land use rights) are important in land use decisions. Even though one quarter of households reported insufficient land resources to maintain soil fertility, few actually indicated that their choices were constrained by land availability. In fact, many cleared much younger fallows than strictly necessary based on the age of fallows available in their land holdings – even those with fallows of sufficient age to maintain long-term productivity. This paper outlines an approach to quantify information about the household preferences that influence land use decisions, discusses the implications of these decision criteria for land use intensification and uses them to model household decision-making in a way that effectively simulates the spatial and dynamic mosaic of land use characteristic of shifting cultivation. Not only are non-productivity related decision criteria important in land use decisions in general; they also have a significant impact on land use intensification. In fact, the research described here demonstrates that both household-specific preferences and household-specific initial conditions can lead to intensification of land use apart from that arising due to increasing population density.

10aHousehold modelling10aIntensification10aPreferences10aShifting cultivation10aSpatiotemporal modelling10aSustainable forest use1 aBrown, Douglas, R u//www.simulistics.com/publications/personal-preferences-and-intensification-land-use-their-impact-southern-cameroonian-sla