A discrete forest in a continuous landscape : investigating interactions between natural resource management and sustainable development

Summary Forests are key ecosystems of the earth and associated with a large range of functions. Many of these functions are beneficial to humans and are referred to as ecosystem services. Sustainable development requires that all relevant ecosystem services are quantified, managed and monitored equally. Natural resource management therefore targets the services associated with ecosystems. The main hypothesis of this thesis is that the spatial and temporal domains of relevant services do not correspond to a discrete forest ecosystem. As a consequence, the services are not quantified, managed and monitored in an equal and sustainable manner. The thesis aims were therefore to test this hypothesis, establish an improved conceptual approach and provide spatial applications for the relevant land cover and structure variables. The study was carried out in western Switzerland and based primarily on data from a countrywide landscape inventory. This inventory is part of the third Swiss national forest inventory and assesses continuous landscape variables based on a regular sampling of true colour aerial imagery. In addition, land cover variables were derived from Landsat 5 TM passive sensor data and land structure variables from active sensor data from a small footprint laserscanning system. The results confirmed the main hypothesis, as relevant services did not scale well with the forest ecosystem. Instead, a new conceptual approach for sustainable management of natural resources was described. This concept quantifies the services as a continuous function of the landscape, rather than a discrete function of the forest ecosystem. The explanatory landscape variables are therefore called continuous fields and the forest becomes a dependent and function-driven management unit. Continuous field mapping methods were established for land cover and structure variables. In conclusion, the discrete forest ecosystem is an adequate planning and management unit. However, monitoring the state of and trends in sustainability of services requires them to be quantified as a continuous function of the landscape. Sustainable natural resource management iteratively combines the ecosystem and gradient approaches. R��sum�� Les for��ts sont des ��cosyst��mes-cl��s de la terre et on leur attribue un grand nombre de fonctions. Beaucoup de ces fonctions sont b��n��fiques pour l'homme et sont nomm��es services ��cosyst��miques. Le d��veloppement durable exige que ces services ��cosyst��miques soient tous quantifi��s, g��r��s et surveill��s de fa��on ��gale. La gestion des ressources naturelles a donc pour cible les services attribu��s aux ��cosyst��mes. L'hypoth��se principale de cette th��se est que les domaines spatiaux et temporels des services attribu��s �� la for��t ne correspondent pas �� un ��cosyst��me discret. Par cons��quent, les services ne sont pas quantifi��s, am��nag��s et surveill��s d'une mani��re ��quivalente et durable. Les buts de la th��se ��taient de tester cette hypoth��se, d'��tablir une nouvelle approche conceptuelle de la gestion des ressources naturelles et de pr��parer des applications spatiales pour les variables paysag��res et structurelles appropri��es. L'��tude a ��t�� men��e en Suisse occidentale principalement sur la base d'un inventaire de paysage �� l'��chelon national. Cet inventaire fait partie du troisi��me inventaire forestier national suisse et mesure de fa��on continue des variables paysag��res sur la base d'un ��chantillonnage r��gulier sur des photos a��riennes couleur. En outre, des variables de couverture ? terrestre ont ��t�� d��riv��es des donn��es d'un senseur passif Landsat 5 TM, ainsi que des variables structurelles, d��riv��es du laserscanning, un senseur actif. Les r��sultats confirment l'hypoth��se principale, car l'��chelle des services ne correspond pas �� celle de l'��cosyst��me forestier. Au lieu de cela, une nouvelle approche a ��t�� ��labor��e pour la gestion durable des ressources naturelles. Ce concept repr��sente les services comme une fonction continue du paysage, plut��t qu'une fonction discr��te de l'��cosyst��me forestier. En cons��quence, les variables explicatives de paysage sont d��nomm��es continuous fields et la for��t devient une entit�� d��pendante, d��finie par la fonction principale du paysage. Des m��thodes correspondantes pour la couverture terrestre et la structure ont ��t�� ��labor��es. En conclusion, l'��cosyst��me forestier discret est une unit�� ad��quate pour la planification et la gestion. En revanche, la surveillance de la durabilit�� de l'��tat et de son ��volution exige que les services soient quantifi��s comme fonction continue du paysage. La gestion durable des ressources naturelles joint donc l'approche ��cosyst��mique avec celle du gradient de mani��re it��rative.

A Negotiation Style Recommender Based on Computational Ecology in Open Negotiation Environments

The system described herein represents the first example of a recommender system in digital ecosystems where agents negotiate services on behalf of small companies. The small companies compete not only with price or quality, but with a wider service-by-service composition by subcontracting with other companies. The final result of these offerings depends on negotiations at the scale of millions of small companies. This scale requires new platforms for supporting digital business ecosystems, as well as related services like open-id, trust management, monitors and recommenders. This is done in the Open Negotiation Environment (ONE), which is an open-source platform that allows agents, on behalf of small companies, to negotiate and use the ecosystem services, and enables the development of new agent technologies. The methods and tools of cyber engineering are necessary to build up Open Negotiation Environments that are stable, a basic condition for predictable business and reliable business environments. Aiming to build stable digital business ecosystems by means of improved collective intelligence, we introduce a model of negotiation style dynamics from the point of view of computational ecology. This model inspires an ecosystem monitor as well as a novel negotiation style recommender. The ecosystem monitor provides hints to the negotiation style recommender to achieve greater stability of an open negotiation environment in a digital business ecosystem. The greater stability provides the small companies with higher predictability, and therefore better business results. The negotiation style recommender is implemented with a simulated annealing algorithm at a constant temperature, and its impact is shown by applying it to a real case of an open negotiation environment populated by Italian companies

Species distributions and interactions in a changing world : from understanding to forecasting

Les ��cosyst��mes fournissent de nombreuses ressources et services ��cologiques qui sont utiles �� la population humaine. La biodiversit�� est une composante essentielle des ��cosyst��mes et maintient de nombreux services. Afin d'assurer la permanence des services ��cosyst��miques, des mesures doivent ��tre prises pour conserver la biodiversit��. Dans ce but, l'acquisition d'informations d��taill��es sur la distribution de la biodiversit�� dans l'espace est essentielle. Les mod��les de distribution d'esp��ces (SDMs) sont des mod��les empiriques qui mettent en lien des observations de terrain (pr��sences ou absences d'une esp��ce) avec des descripteurs de l'environnement, selon des courbes de r��ponses statistiques qui d��crive la niche r��alis��e des esp��ces. Ces mod��les fournissent des projections spatiales indiquant les lieux les plus favorables pour les esp��ces consid��r��es. Le principal objectif de cette th��se est de fournir des projections plus r��alistes de la distribution des esp��ces et des communaut��s en montagne pour le climat pr��sent et futur en consid��rant non-seulement des variables abiotiques mais aussi biotiques. Les r��gions de montagne et l'��cosyst��me alpin sont tr��s sensibles aux changements globaux et en m��me temps assurent de nombreux services ��cosyst��miques. Cette th��se est s��par��e en trois parties : (i) fournir une meilleure compr��hension du r��le des interactions biotiques dans la distribution des esp��ces et l'assemblage des communaut��s en montagne (ouest des Alpes Suisses), (ii) permettre le d��veloppement d'une nouvelle approche pour mod��liser la distribution spatiale de la biodiversit��, (iii) fournir des projections plus r��alistes de la distribution future des esp��ces ainsi que de la composition des communaut��s. En me focalisant sur les papillons, bourdons et plantes vasculaires, j'ai d��tect�� des interactions biotiques importantes qui lient les esp��ces entre elles. J'ai ��galement identifi�� la signature du filtre de l'environnement sur les communaut��s en haute altitude confirmant l'utilit�� des SDMs pour reproduire ce type de processus. A partir de ces ��tudes, j'ai contribu�� �� l'am��lioration m��thodologique des SDMs dans le but de pr��dire les communaut��s en incluant les interactions biotiques et ��galement les processus non-d��terministes par une approche probabiliste. Cette approche permet de pr��dire non-seulement la distribution d'esp��ces individuelles, mais ��galement celle de communaut��s dans leur entier en empilant les projections (S-SDMs). Finalement, j'ai utilis�� cet outil pour pr��dire la distribution d'esp��ces et de communaut��s dans le pass�� et le futur. En particulier, j'ai mod��lis�� la migration post-glaciaire de Trollius europaeus qui est �� l'origine de la structure g��n��tique intra-sp��cifique chez cette esp��ce et ��valu�� les risques de perte face au changement climatique. Finalement, j'ai simul�� la distribution des communaut��s de bourdons pour le 21e si��cle afin d'��valuer les changements probables dans ce groupe important de pollinisateurs. La diversit�� fonctionnelle des bourdons va ��tre alt��r��e par la perte d'esp��ces sp��cialistes de haute altitude et ceci va influencer la pollinisation des plantes en haute altitude. - Ecosystems provide a multitude of resources and ecological services, which are useful to human. Biodiversity is an essential component of those ecosystems and guarantee many services. To assure the permanence of ecosystem services for future generation, measure should be applied to conserve biodiversity. For this purpose, the acquisition of detailed information on how biodiversity implicated in ecosystem function is distributed in space is essential. Species distribution models (SDMs) are empirical models relating field observations to environmental predictors based on statistically-derived response surfaces that fit the realized niche. These models result in spatial predictions indicating locations of the most suitable environment for the species and may potentially be applied to predict composition of communities and their functional properties. The main objective of this thesis was to provide more accurate projections of species and communities distribution under current and future climate in mountains by considering not solely abiotic but also biotic drivers of species distribution. Mountain areas and alpine ecosystems are considered as particularly sensitive to global changes and are also sources of essential ecosystem services. This thesis had three main goals: (i) a better ecological understanding of biotic interactions and how they shape the distribution of species and communities, (ii) the development of a novel approach to the spatial modeling of biodiversity, that can account for biotic interactions, and (iii) ecologically more realistic projections of future species distributions, of future composition and structure of communities. Focusing on butterfly and bumblebees in interaction with the vegetation, I detected important biotic interactions for species distribution and community composition of both plant and insects along environmental gradients. I identified the signature of environmental filtering processes at high elevation confirming the suitability of SDMs for reproducing patterns of filtering. Using those case-studies, I improved SDMs by incorporating biotic interaction and accounting for non-deterministic processes and uncertainty using a probabilistic based approach. I used improved modeling to forecast the distribution of species through the past and future climate changes. SDMs hindcasting allowed a better understanding of the spatial range dynamic of Trollius europaeus in Europe at the origin of the species intra-specific genetic diversity and identified the risk of loss of this genetic diversity caused by climate change. By simulating the future distribution of all bumblebee species in the western Swiss Alps under nine climate change scenarios for the 21st century, I found that the functional diversity of this pollinator guild will be largely affected by climate change through the loss of high elevation specialists. In turn, this will have important consequences on alpine plant pollination.

Wandel der Biodiversit��t in der Schweiz seit 1900: ist die Talsohle erreicht?

Die Biodiversit��t ist unsere Lebensgrundlage - ihr ��konomischer, ��kologischer, sozialer und ��sthetischer Wert kann nicht hoch genug eingesch��tzt werden. Im Jahr 2003 beschlossen die Umweltminister Europas daher, den Verlust der Biodiversit��t bis ins Jahr 2010 zu stoppen. Haben wir dieses Ziel erreicht?Die vorliegende Studie des Forum Biodiversit��t Schweiz gibt fundierte Antworten auf diese Frage. Die umfassende Analyse zeigt auf Basis der besten verf��gbaren Daten und differenziert f��r unterschiedliche Aspekte der biologischen Vielfalt, wie sich die Biodiversit��t in der Schweiz seit 1900 entwickelt hat. Die Resultate zeigen, dass weiterhin ein gro��er Handlungsbedarf besteht.

Movement, impacts and management of plant distributions in response to climate change: insights from invasions

A major challenge in this era of rapid climate change is to predict changes in species distributions and their impacts on ecosystems, and, if necessary, to recommend management strategies for maintenance of biodiversity or ecosystem services. Biological invasions, studied in most biomes of the world, can provide useful analogs for some of the ecological consequences of species distribution shifts in response to climate change. Invasions illustrate the adaptive and interactive responses that can occur when species are confronted with new environmental conditions. Invasion ecology complements climate change research and provides insights into the following questions: i) how will species distributions respond to climate change? ii) how will species movement affect recipient ecosystems? and iii) should we, and if so how can we, manage species and ecosystems in the face of climate change? Invasion ecology demonstrates that a trait-based approach can help to predict spread speeds and impacts on ecosystems, and has the potential to predict climate change impacts on species ranges and recipient ecosystems. However, there is a need to analyse traits in the context of life-history and demography, the stage in the colonisation process (e.g., spread, establishment or impact), the distribution of suitable habitats in the landscape, and the novel abiotic and biotic conditions under which those traits are expressed. As is the case with climate change, invasion ecology is embedded within complex societal goals. Both disciplines converge on similar questions of "when to intervene?" and "what to do?" which call for a better understanding of the ecological processes and social values associated with changing ecosystems.

Nature, evolution and characterisation of rhizospheric chemical exudates affecting root herbivores

Similar to aboveground herbivores, root-feeding insects must locate and identify suitable resources. In the darkness of soil, they mainly rely on root chemical exudations and, therefore, have evolved specific behaviours. Because of their impact on crop yield, most of our knowledge in belowground chemical ecology is biased towards soil-dwelling insect pests. Yet the increasing literature on volatile-mediated interactions in the ground underpins the great importance of chemical signalling in this ecosystem and its potential in pest control. Here, we explore the ecology and physiology of these chemically based interactions. An evolutionary approach reveals interesting patterns in the response of insects to particular classes of volatile or water-soluble organic compounds commonly emitted by roots. Food web analyses reasonably support that volatiles are used as long-range cues whereas water-soluble molecules serve in host acceptance/rejection by the insect; however, data are still scarce. As a case study, the chemical ecology of Diabrotica virgifera virgifera is discussed and applications of belowground signalling in pest management are examined. Soil chemical ecology is an expanding field of research and will certainly be a hub of our understanding of soil communities and subsequently of the management of belowground ecosystem services.

Pollution stress on aquatic microbial communities

Thousands of chemical compounds enter the natural environment but many have unknown effects and consequences, in particular at low concentrations. This thesis work contributes to our understanding of pollution effects by using bacteria as test organisms. Bacteria are important for this question because some of them degrade and transform pollutants into less harmful compounds, but secondly because they themselves can be inhibited in their reproduction by exposure to toxic compounds. When inhibitory effects occur this may change the composition of the microbial com��munity in the long run, leading to altered or diminished ecosystem services by those communities. As a result chemicals of anthropogenic origin may accumulate and per��sist in the environment, and finally, affect higher organisms as well. In addition to acquiring basic understanding of pollutant effects at low concentrations on bacterial communities an applied goal of this thesis work was to develop bacteria-based tests to screen new organic chemicals for toxicity and biod��gradation. In the first part of this work we developed a flow cytometry-based assay on SYT09 plus ethidium-bromide or propidium-iodide stained cells of Pseudomonas ��uorescens exposed or not to a variety of pollutants under oligotrophic growth conditions. Flow cytometry (FC) allows fast and accurate counting of bacterial cells under simul��taneous assessment of their physiological state, in particular in combination with different fluorescent dyes. Here we employed FC and fluorescent dyes to monitor the effect that pollutants may exert on Pseudomonas ��uorescens SV3. First we designed an oligotrophic growth test, which enabled us to follow population growth at low densities (104 - 10 7 cells per ml) using 0.1 mM sodium acetate as carbon source. Cells in the oligotrophic milieu were then exposed or not to a variety of common pollutants, such as 2-chlorobiphenyl (2CBP), naphthalene (NAH), 4-chlorophenol (4CP), tetradecane (TD), mercury chloride (HgCl2) or benzene, in different dosages. Exposed culture samples were stained with SYT09 (green fluorescent dye binding nucleic acids, generally staining all cells) in combination with propidium iodide (PI) or ethidium bromide (EB), both dyes being membrane integrity indicators. We ob- served that most of the tested compounds decreased population growth in a dosage- dependent manner. SYT09/PI or SYT09/EB staining then revealed that chemical exposure led to arisal of subpopulations of live and injured or dead cells. By modeling population growth on the total cell numbers in population or only the subpopulation of live cells we inferred that even in stressed populations live cells multiply at rates no different to unexposed controls. The net decrease in population growth would thus be a consequence of more and more cells being not able to multiply at all, rather than all cells multiplying at slower rates. In addition, the proportion of injured cells correlated to the compound dosage. We concluded that the oligotrophic test may be useful to asses toxicity of unknown chemicals on a variety of model bacteria. Mul��tiple tests can be run in parallel and effects are rapidly measured within a period of 8 hours. Interestingly, in the same exposure tests with P. fluorescens SV3 we observed that some chemicals which did not lead to a reduction of net population growth rates did cause measurable effects on live cells. This was mainly observed in cells within the live subpopulation as an increase of the EB fluorescence signal. We showed that SYT09/EB is a more useful combination of dyes than SYT09/PI because PI fluorescence tend to increase only when cells are effectively dead, but not so much in live cells (less then twofold). In contrast, EB geometric mean fluorescence in live cells increased up to eightfold after exposure to toxic compounds. All compounds even at the lowest concentration caused a measurable increase in EB geometric mean fluorescence especially after 2 h incubation time. This effect was found to be transient for cells exposed to 2CBP and 4CP, but chronic for cells incubated with TD and NAH (ultimately leading to cell death). In order to understand the mechanism underlying the observed effects we used known membrane or energy uncouplers. The pattern of EB signal increase in chemical-exposed populations resembled mostly that of EDTA, although EB fluorescence in EDTA-treated or pasteurized cells was even higher than after exposure to the four test chemicals. We conclude that the ability of cells to efflux EB under equilibrium conditions is an appropriate measure for the potential of a chemical to exert toxicity. Since most bacterial species possess efflux systems for EB that all require cellular energy, our test should be more widely relevant to infer toxicity effects of chemical exposure on the physiological status of the bacterial cell. To better understand the effect of toxicant exposure on efflux defense systems, we studied 2-hydroxybiphenyl toxicity to Pseudomonas azeiaica HBP1. We showed that 2-HBP exerts toxicity even to P. azelaica HBP1, but only at concentrations higher than 0.5 mM. Above this concentration transient loss of membrane polarization and integrity occurred, which we conclude from staining of growing cells with fluorescent dyes. Cells finally recover and resume growth on 2HBP. The high resistance of P. azelaica HBP1 to 2-HBP was found to be the result of an efficient MexABOprM- type efflux pump system counteracting passive influx of this compound into the membrane and cellular interior. Mutants with disrupted mexA, mexB and oprM genes did no longer grow on 2-HBP at concentrations above 100 μΜ, whereas below this concentration we found 2-HBP-concentration dependent decrease of growth rate. The MexAB-OprM system in P. azeiaica HBP1 is indeed an efflux pump for ethidium bromide as well. By introducing gfp reporter fusions responsive to intracellular 2- HBP concentrations into HBP1 wild-type or the mutants we demonstrated that 2HBP enters into the cells in a similar way. In contrast, the reporter system in the wild-type cells does not react to 2-HBP at an outside concentration of 2.4 μΜ, whereas in mutant cells it does. This suggests that wild-type cells pump 2-HBP to the outside very effectively preventing accumulation of 2-HBP. 2HBP metabolism, therefore, is not efficient enough to lower the intracellular concentration and prevent toxicity. We conclude that P. azelaica HBP1 resistance to 2-HBP is mainly due to an efficient efflux system and that 2HBP in high concentrations exerts narcotic effects on the bacterial membrane. In the part of this thesis, we investigated the possibilities of bacteria to degrade pollutants at low concentrations (1 mg per L and below). As test components we used 2-hydroxybiphenyl, antibiotics and a variety of fragrances, many of which are known to be difficult to biodegrade. By using accurate counting of low numbers of bacterial cells we could demonstrate that specific growth on these compounds is possible. We demonstrated the accuracy of FC counting at low cell numbers (down to 103 bacterial cells per ml). Then we tested whether bacterial population growth could be specifically monitored at the expense of low substrate concentrations, us��ing P. azelaica HBP1. A perfect relationship was found between growth rate, yield and 2-HBP concentrations in the range of 0.1 up to 5 mg per L. Mixing P. azelaica within sludge, however, suggested that growth yields in a mixed community can be much lower than in pure culture, perhaps because of loss of metabolic intermediates. We then isolated new strains from activated sludge using 2-HBP or antibiotics (Nal, AMP, SMX) at low concentrations (0.1-1 mg per L) as sole carbon and energy sub��strate and PAO microdishes. The purified strains were then examined for growth on their respective substrate, which interestingly, showed that all strains can not with��stand higher than 1 or 10 mg per L concentrations of target substrate. Thus, bacteria must exist that contribute to compound degradation at low pollutant concentrations but are inhibited at higher concentrations. Finally we tested whether specific biomass growth (in number of cells) at the expense of pollutants can also be detected with communities as starting material. Hereto, we focused on a number of fragrance chemicals and measured community biomass increase by flow cytometry cell counting on two distinct starter communities: (i) diluted Lake Geneva water, and dilute activated sludge from a wastewater treatment plant. We observed that most of the test compounds indeed resulted in significant biomass increase in the starter community compared to a no-carbon added control, but activated sludge and lake Geneva water strongly differed (almost mutually ex��clusive) in their capacity to degrade the test chemicals. In two cases for activated sludge the same type of microbial community developed upon compound exposure, as concluded from transcription fragment length polymorphism analysis on community purified and PCR amplified 16S rRNA gene fragments. To properly test compound biodegradability it is thus important to use starter communities of different origin. We conclude that FC counting can be a valuable tool to screen chemicals for their biodegradability and toxicity. - Des milliers de produits chimiques sont lib��r��s dans l'environnement mais beaucoup ont des effets inconnus, en particulier �� basses concentrations. Ce travail de th��se contribue �� notre comprehension des effets de la pollution en utilisant des bacteries comme des organismes-tests. Les bacteries sont importantes pour etudier cette ques��tion car certaines d'entre elles peuvent degrader ou transformer les polluants, mais ��galement parce qu'elles-mmes peuvent tre inhibees dans leur reproduction apr��s avoit ete exposees �� ces composes toxiques. Quand des effets inhibiteurs ont lieu, la composition de la communaut�� microbienne peut tre changee �� long terme, ce qui m��ne �� une reduction du service d'ecosyst��me offert par ces communaut��s. En consequence, apr��s leur liberation dans l'environnement, les produits chimiques d'origine anthropogenique peuvent soit s'y accumuler et per��sister, exerant ainsi des effets encore inconnus sur les organismes vivants. En plus d'acqu��rir des connaissances de base sur les effets des polluants �� basses concentra��tions sur les communaut��s microbiennes, un but applique de cette th��se ��tait de d��velopper des tests bases sur les bacteries afin d'identifier de nouveau composes pour leur toxicit�� ou leur biod��gradation. Dans la premi��re partie de ce travail, nous avons developpe un test base sur la cytometrie de flux (FC) sur des cellules de Pseudomonas fluorescens colorees par du bromure d'ethidium ou de l'iodure de propidium et exposees ou non �� une palette de polluants sous des conditions de croissance oligotrophique. La cytometrie de flux est une technique qui conna��t de nombreuses applications dans la microbiologie environ��nementale. Cela est principalement du au fait qu'elle permet un comptage rapide et precis ainsi que l'��valuation de l'��tat physiologique, en particulier lorsqu'elle est combin��e h des colorations fluorescentes. Ici, nous avons utilise la technique FC et des colorants fluorescents afin de mesurer l'effet que peuvent exercer certains pollu��ants sur Pseudomonas ��uorescens SV3 . D'abord nous avons conu des tests oligo- trophiques qui nous permettent de suivre la croissance compl��te de cellules en culture h des densites faibles (104 -10 7 cellules par ml), sur de l'acetate de sodium �� 0.1 mM, en presence ou absence de produits chimiques (2-chlorobiphenyl (2CBP), naphthal��ne (NAH), 4-chlorophenol (4CP), tetradecane (TD), chlorure de mercure(II) (HgCl2)) �� diff��rentes concentrations. Afin de montrer le devenir des bacteries tant au niveau de la cellule individuelle que celui de la population globale, apr��s exposition �� des series de composes chimiques, nous avons compte les cellules colorees avec du SYT09 (col��orant fluorescent vert des acides nucl��iques pour la discrimination des cellules par rapport au bruit de fond) en combinaison avec l'iodure de propidium (PI) ou le bromure d'ethidium (EB), indicateurs de l'int��grit�� de la membrane cellulaire avec FC. Nous avons observe que de nombreux composes testes avaient un effet sur la croissance bacterienne, resultant en une baisse du taux de reproduction de la pop��ulation. En outre, la double coloration que nous avons utilisee dans cette etude SYT09/PI ou SYT09/EB a montre que les produits chimiques testes induisaient une reponse heterog��ne des cellules dans la population, divisant celle-ci en sous- populations "saine", "endommagee" ou "morte". Les nombres de cellules �� partir du comptage et de la proportion de celles "saines" et "endommagees/mortes" ont ensuite ete utilises pour modeliser la croissance de P. ��uorescens SV3 exposee aux produits chimiques. La reduction nette dans la croissance de population est une consequence du fait que de plus en plus de cellules sont incapables de se reproduire, plutt que du fait d'une croissance plus lente de l'ensemble de la population. De plus, la proportion de cellules endommagees est correllee au dosage du compose chimique. Les r��sultats obtenus nous ont permis de conclure que le test oligotrophique que nous avons developpe peut tre utilise pour l'��valuation de la toxicit�� de produits chimiques sur diff��rents mod��les bacteriens. Des tests multiples peuvent tre lances en parall��le et les effets sont mesures en l'espace de huit heures. Par ailleurs, nous en d��duisons que les produits chimiques exerc��nt un effet sur la croissance des cellules de P. ��uorescens SV3, qui est heterog��ne parmi les cellules dans la population et depend du produit chimique. Il est int��ressant de noter que dans les mmes tests d'exposition avec P. ��uorescens SV3, nous avons observe que certains composes qui n'ont pas conduit �� une reduction du taux de la croissance nette de la population, ont cause des effets mesurables sur les cellule saines. Ceci a ete essentiellement observe dans la portion "saine" des cellules en tant qu'augmentation du signal de la fluorescence de 1ΈΒ. D'abord nous avons montre que SYT09/EB ��tait une com��binaison de colorants plus utile que celle de SYT09/PI parce que la fluorescence du PI a tendance �� augmenter uniquement lorsque les cellules sont effectivement mortes, et non pas dans les cellules saines (moins de deux fois plus). Par opposi��tion, la fluorescence moyenne de l'EB dans les cellules saines augmente jusqu'�� huit fois plus apr��s exposition aux composes toxiques. Tous les composes, mme aux plus basses concentrations, induisent une augmentation mesurable de la fluorescence moy��enne de 1ΈΒ, plus particuli��rement apr��s deux heures d'incubation. Cet effet s'est revele tre transitoire pour les cellules exposees aux 2CNP et 4CP, mais est chro��nique pour les cellules incubees avec le TD et le NAH (entranant la mort cellulaire). Afin de comprendre les m��canismes qui sous-tendent les effets observes, nous avons utilise des decoupleurs d'energie ou de membrane. L'augmentation du signal EB dans les populations causee par des produits chimiques ressemblait �� celle exerce par le chelateur des ions divalents EDTA. Cependant, les intensit��s du signal EB des cellules exposees aux produits chimiques testees n'ont jamais atteint les valeurs des cellules traitees avec l'EDTA ou pasteurises. Nous en concluons que le test oli- gotrophique utilisant la coloration (SYT09/)EB des cellules exposees ou non �� un produit chimique est utile afin d'evaluer l'effet toxique exerce par les polluants sur la physiologie bacterienne. Afin de mieux comprendre la reaction d'un syst��me de defense par pompe �� efflux apr��s exposition �� une toxine, nous avons ��tudi�� la toxicit�� du 2-hydroxybiphenyl (2-HBP) sur Pseudomonas azeiaica HBP1. Nous avons montre que le 2-HBP exerce une toxicit�� mme sur HBP1, mais uniquement �� des concentrations sup��rieures �� 0.5 mM. Au-dessus de cette concentration, des pertes transitoires d'int��grit�� et de polarization membranaire ont lieu, comme cela nous a ete montre par coloration des cellules en croissance. Les cellules sont finalement capables de se r��tablir et de reprendre leur croissance sur 2-HBP. La forte resistance de P. azeiaica HBP1 h 2-HBP physiologie bacterienne s'est revele tre le r��sultat d'un syst��me de pompe h efflux de type MexABOprM qui contre-balance l'influx passif de ce compose h travers la membrane. Nous avons montre, en construisant des mutants avec des insertions dans les g��nes mexA, mexB and oprM et des fusions avec le g��ne rapporteur gfp, que l'alt��ration de n'importe quelle partie du syst��me d'efflux conduisait �� accro��tre l'accumulation de 2-HBP dans la cellule, en comparaison avec la souche sauvage HBP1, provoquant une diminution de la resistance au 2-HBP ainsi qu'une baisse du taux de reproduction des cellules. Des syst��mes d'efflux similaires sont r��pandus chez de nombreuses esp��ces bact��riennes. Ils seraient responsables de la resistance aux produits chimiques tels que les colorants fluorescents (bromure d'ethidium) et des antibiotiques. Nous concluons que la resistance de P. azelaica HBP1 �� 2-HBP est principalement due �� un syst��me d'efflux efficace et que 2-HBP, �� des concentrations elevees, exerce un effet delet��re sur la membrane bacterienne. En se basant sur le comptage des cellules avec la FC, nous avons developpe ensuite une methode pour evaluer la biodegradabilite de polluants tels que le 2-HBP ainsi que les antibiotiques (acide nalidixique (Nal), ampicilline (AMP) ou sulfamethoxazole (SMX)) �� de faibles concentrations lmg par L et moins), par le suivi de la croissance sp��cifique sur le compose de cultures microbiennes pures et mixtes. En utilisant un comptage precis de faibles quantit��s de cellules nous avons pu demontrer que la croissance sp��cifique sur ces composes est possible. Nous avons pu illustrer la precision du comptage par cytometrie de flux �� faible quantit�� de cellules (jusqu'�� 10 3 cellules par ml). Ensuite, nous avons teste s'il ��tait possible de suivre dynamiquement la croissance de la population de cellules sur faibles concentrations de substrats, en utilisant P. azelaica HBP1. Une relation parfaite a ete trouvee entre le taux de croissance, le rendement et les concentrations de 2-HBP (entre 0.1 et 5 mg par L). En m��langeant HBP1 �� de la boue active, nous avons pu montrer que le rendement en communaut�� mixtes pouvait tre bien inf��rieur qu'en culture pure. Ceci ��tant peut tre le r��sultat d'une perte d'interm��diaires m��taboliques. Nous avons ensuite isole de nouvelles souches �� partir de la boue active en utilisant le 2-HBP ou des antibiotiques (Nal, AMP, SMX) h basses concentrations (0.1-1 mg par L) comme seules sources de carbone et d'energie. En combinaison avec ceci, nous avons ��galement utilise des microplaques PAO. Les souches purifiees ont ensuite ete examinees pour leurs croissances sur leurs substrats respectifs. De faon int��ressante, toutes ces souches ont montre qu'elles ne pouvaient pas survivre �� des concentrations de substrats sup��rieures �� 1 ou 10 mg par L. Ainsi, il existe des bacteries qui contribuent �� la degradation de composes �� basses concentrations de polluant mais sont inhibes lorsque ces concentrations deviennent plus hautes. Finalement, nous avons cherche �� savoir s'il est possible de detecter une croissance sp��cifique �� une biomasse au depend d'un polluant, en partant d'une communaut�� microbienne. Ainsi, nous nous sommes concentre sur certains composes et avons mesure l'augmentation de la biomasse d'une communaut�� grce �� la cytometrie de flux. Nous avons compte deux communaut��s de depart distinctes: (i) une dilution d'eau du Lac L��man, et une dilution de boue active d'une station d'��puration. Nous avons observe que la plupart des composes testes ont entrane une augmentation de la biomasse de depart par rapport au control sans addition de source de carbone. N��anmoins, les ��chantillons du lac L��man et de la station d'��puration diff��raient largement (s'excluant mutuellement l'un l'autre) dans leur capacit�� �� degrader les composes chimiques. Dans deux cas provenant de la station d'��puration, le mme type de communaut�� microbienne s'est developpe apr��s exposition aux composes, comme l'a d��montr�� l'analyse TRFLP sur les fragments d'ARN 16S purifie de la communaut�� et amplifie par PCR. Afin de tester correctement la biodegradabilite d'un compose, il est donc important d'utiliser des communaut��s de depart de diff��rentes origines Nous en concluons que le comptage par cytometrie de flux peut tre un outil de grande utilit�� pour mettre en valeur la biodegradabillite et la toxicit�� des composes chimiques.

Do PES Improve the Governance of Forest Restoration?

Payments for Environmental Services (PES) are praised as innovative policy instruments and they influence the governance of forest restoration efforts in two major ways. The first is the establishment of multi-stakeholder agencies as intermediary bodies between funders and planters to manage the funds and to distribute incentives to planters. The second implication is that specific contracts assign objectives to land users in the form of conditions for payments that are believed to increase the chances for sustained impacts on the ground. These implications are important in the assessment of the potential of PES to operate as new and effective funding schemes for forest restoration. They are analyzed by looking at two prominent payments for watershed service programs in Indonesia-Cidanau (Banten province in Java) and West Lombok (Eastern Indonesia)-with combined economic and political science approaches. We derive lessons for the governance of funding efforts (e.g., multi-stakeholder agencies are not a guarantee of success; mixed results are obtained from a reliance on mandatory funding with ad hoc regulations, as opposed to voluntary contributions by the service beneficiary) and for the governance of financial expenditure (e.g., absolute need for evaluation procedures for the internal governance of farmer groups). Furthermore, we observe that these governance features provide no guarantee that restoration plots with the highest relevance for ecosystem services are targeted by the PES

The Economics of Dead Zones: Linking Externalities from the Land to their Consequences in the Sea, October 2012,

The purpose of this review and analysis is to provide a basic understanding of the issues related to worldwide hypoxic zones and the range of economic questions sorely in need of answers. We begin by describing the causes and extent of hypoxic zones worldwide, followed by a review of the evidence concerning ecological effects of the condition and impacts on ecosystem services. We describe what is known about abatement options and cost effective policy design before turning to an analysis of the large, seasonally recurring hypoxic zone in the Gulf of Mexico. We advance the understanding of this major ecological issue by estimating the relationship between pollutants (nutrients) and the areal extent of the hypoxic zone. This ���production function��� relationship suggests that both instantaneous and legacy contributions of nutrients contribute to annual predictions of the size of the zone, highlighting concerns that ecologists have raised about lags in the recovery of the system and affirms the importance of multiple nutrients as target pollutants. We conclude with a discussion of critical research needs to provide input to policy formation.

Ain't no mountain high enough: plant invasions reaching new elevations

Most studies of invasive species have been in highly modified, lowland environments, with comparatively little attention directed to less disturbed, high-elevation environments. However, increasing evidence indicates that plant invasions do occur in these environments, which often have high conservation value and provide important ecosystem services. Over a thousand non-native species have become established in natural areas at high elevations worldwide, and although many of these are not invasive, some may pose a considerable threat to native mountain ecosystems. Here, we discuss four main drivers that shape plant invasions into high-elevation habitats: (1) the (pre-)adaptation of non-native species to abiotic conditions, (2) natural and anthropogenic disturbances, (3) biotic resistance of the established communities, and (4) propagule pressure. We propose a comprehensive research agenda for tackling the problem of plant invasions into mountain ecosystems, including documentation of mountain invasion patterns at multiple scales, experimental studies, and an assessment of the impacts of non-native species in these systems. The threat posed to high-elevation biodiversity by invasive plant species is likely to increase because of globalization and climate change. However, the higher mountains harbor ecosystems where invasion by non-native species has scarcely begun, and where science and management have the opportunity to respond in time.

Resilient housing : a new resource-oriented approach

The institutional regimes framework has previously been applied to the institutional conditions that support or hinder the sustainability of housing stocks. This resource-based approach identifies the actors across different sectors that have an interest in housing, how they use housing, the mechanisms affecting their use (public policy, use rights, contracts, etc.) and the effects of their uses on the sustainability of housing within the context of the built environment. The potential of the institutional regimes framework is explored for its suitability to the many considerations of housing resilience. By identifying all the goods and services offered by the resource 'housing stock', researchers and decision-makers could improve the resilience of housing by better accounting for the ecosystem services used by housing, decreasing the vulnerability of housing to disturbances, and maximizing recovery and reorganization following a disturbance. The institutional regimes framework is found to be a promising tool for addressing housing resilience. Further questions are raised for translating this conceptual framework into a practical application underpinned with empirical data.

Sustainability, certification, and regulation of biochar

Biochar has a relatively long half-life in soil and can fundamentally alter soil properties, processes, and ecosystem services. The prospect of global-scale biochar application to soils highlights the importance of a sophisticated and rigorous certification procedure. The objective of this work was to discuss the concept of integrating biochar properties with environmental and socioeconomic factors, in a sustainable biochar certification procedure that optimizes complementarity and compatibility between these factors over relevant time periods. Biochar effects and behavior should also be modelled at temporal scales similar to its expected functional lifetime in soils. Finally, when existing soil data are insufficient, soil sampling and analysis procedures need to be described as part of a biochar certification procedure.

Propuesta de cursos de capacitaci��n sobre lecciones aprendidas en Costa Rica

El presente proyecto ha sido realizado entre Octubre de 2013 y Febrero de 2014 por un equipo de estudiantes de la licenciatura de Ciencias Ambientales de la Universidad Aut��noma de Barcelona. El objeto de estudio es la propuesta de cursos para la formaci��n de tres p��blicos diferentes, estudiantes, gestores y pol��ticos. Estos cursos se basan en la experiencia de Costa Rica sobre la conservaci��n de la biodiversidad. Costa Rica es un pa��s muy rico en biodiversidad por su clima y sus tierras volc��nicas. Una manera de conservar esta gran variedad de especies es protegiendo gran parte del pa��s con reservas y parques nacionales. La metodolog��a utilizada para llevar a cabo estos cursos es la investigaci��n. Recopilar informaci��n de las diferentes carencias de distintos pa��ses, propuestas pedag��gicas para saber mostrar de manera correcta la informaci��n a cada p��blico meta y basarlos en el cumplimiento de las Metas Aichi, que tratan de mantener la biodiversidad de manera que contribuya al bienestar de la poblaci��n. La intenci��n de estos cursos es ense��ar a los distintos p��blicos meta las experiencias positivas que ha tenido Costa Rica para poder desarrollarse tanto en crecimiento econ��mico como de la poblaci��n conservando su biodiversidad. De manera que en otros pa��ses puedan aprender y a la misma vez beneficiarse con las ideas propuestas en los cursos. El curso propuesto para estudiantes trata sobre los servicios ecosist��micos, reconocidos internacionalmente por su empe��o en la conservaci��n y uso sostenible de la biodiversidad. El dirigido a gestores, que pueden ser empresarios, es sobre la mejora de la calidad de las aguas, un punto importante para este p��blico que ser��n los encargados de gestionar este recurso tan importante para mantener en buen estado de conservaci��n la biodiversidad. Finalmente, se propone un curso dirigido a pol��ticos, donde se explica la idea de bioprospecci��n, un tema que se trabaja en el Instituto Nacional de Biodiversidad de Costa Rica y trata de investigar en los organismos que aportan beneficios tanto econ��micos como en la salud de las personas.

11

The contribution of biodiversity and ecosystem services to our health care needs is significant, both for the development of modern pharmaceuticals (Chivian and Bernstein 2008; Newmann and Cragg 2007; see also chapter on contribution of biodiversity to pharmaceuticals in this volume) and for their uses in traditional medicine (WHO 2013). Long before the rise of pharmaceutical development, societies have been drawing on their traditional knowledge, skills and customary practices, using various resources provided to them by nature to prevent, diagnose and treat health problems. Today, these practices continue to inform health-care delivery at the level of local communities in many places around the world (WHO 2013). In socioecological contexts such as these, several resources used for food, cultural and spiritual purposes are also used as medicines (Unnikrishnan and Suneetha 2012). Traditional medicine practices provide more than health care to these communities; they are considered a way of life and are founded on endogenous strengths, including knowledge, skills and capabilities.