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A decline in the size of fish within a population is concerning. Large-sized fish are ecologically important and valued for social and economic reasons. Following widespread collapses from angling overharvest, the densities of Walleyes Sander vitreus in Albertas lakes increased rapidly with large-minimum-size limits. Anglers were unhappy, however, as catch rates increased (>1 Walleyes*hour-1) but fish remained small and did not exceed the minimum size limit. The two alternate explanations for the small, yet old Walleyes were either compensatory growth because of high density (stunting) or size-selective mortality (overfishing). Size-selective mortality has evolutionary consequences. Paradoxically, the management solutions for these problems are in opposition (more harvest versus less harvest), and a wrong diagnosis could exacerbate the problem. I used nested hypotheses, and implemented active adaptive management at several Alberta lakes, to diagnose the causal mechanism creating the small fish problem. For inferences on the source of the mortality, I analysed backcalculated growth rates from pelvic fins. Walleyes that had fast-growth to an early maturity, and then subsequent slow-growth, had greater survival. This hockey stick-shaped growth allows for successful reproduction while the Walleyes remain below the minimum size limit, avoiding harvest. Using changes to sport fishing regulations, I then modified angler effort and harvest at four different Alberta lakes to increase or decrease size-selective harvest and Walleye densities. I found that size-selective mortality from angling rapidly truncated the population-size structure. With concerns of evolutionary consequences because of evidence of size selective harvest, I used an age- and size-structured, single-species model, parameterized with data from Albertas Walleye fisheries, to evaluate the selectiveness of various management regulations. I found that the 50-cm minimum size limit used to recover Albertas Walleye populations did indeed select for the hockey stick life history, although this regulation allowed for sustainable populations (>5 Walleyes*hectare-1) and angler effort up to 16 angler-hours*ha-1*year-1. The optimal regulation to reduce life history selection and allow for population sustainability was a 40-50 cm harvest-tag regulation. This regulation reversed the selection for the hockey stick life history, yet produced sustainable fish densities and allowed angler effort up to 30 angler-hours*ha-1*year-1. However, increasing angler-noncompliance reduced the sustainability of this regulation. / Wildlife Ecology and Management

Population growth, urbanization and climate change threaten urban water systems. The rise of demands caused by growing urban areas and the potential decrease of water availability caused by the increase of frequency and severity of droughts challenge the continued well-being of society. Due to increasing environmental and financial constraints, water management paradigms have shifted from supply augmentation to demand management, and water conservation initiatives may efficiently decrease water demands to more sustainable levels. To provide reliable assessment of the efficiencies of different demand management strategies, new modeling techniques are needed that can simulate decentralized decisions of consumers and their interactions with the water system. An integrated simulation-optimization framework, based on the paradigm of Complex Adaptive Systems, is developed here to model dynamic interactions and adaptations within social, built, and natural components of urban water systems. The framework goes beyond tradition engineering simulations by incorporating decentralized, heterogeneous and autonomous agents, and by simulating dynamic feedback loops among modeling components. The framework uses modeling techniques including System Dynamics, Cellular Automata, and Agent-based Modeling to simulate housing and population growth, a land use change, residential water consumption, the hydrologic cycle, reservoir operation, and a policy/decision maker. This research demonstrates the applicability of the proposed framework through a series of studies applied to a water supply system of a large metropolitan region that is located in a semi-arid region and suffers recurrently from severe droughts. A set of adaptive demand management strategies, that apply contingency restrictions, land use planning, and water conservation technologies, such as rainwater harvesting systems, are evaluated. A multi-objective Evolutionary Algorithm is coupled with the CAS simulation framework to identify optimal strategies and explore conflicting objectives within a water system. The results demonstrate the benefits of adaptive management by updating management decisions to changing conditions. This research develops a new hydrologic sustainability metric, developed to quantify the stormwater impacts of urbanization. The Hydrologic Footprint Residence captures temporal and spatial hydrologic characteristics of a flood wave passing through a stream segment and is used to assess stormwater management scenarios, including Best Management Practices and Low Impact Development.

Thesis (M.S.)--Humboldt State University, 2006. / Includes bibliographical references (leaves 91-97). Also available via Humboldt Digital Scholar.

O noroeste de São Paulo, transição entre a Floresta Atlântica e o Cerrado, é uma das regiões mais fragmentadas do estado. Investigando a regeneração natural de remanescentes florestais é possível compreender como a diversidade de espécies e os processos ecológicos são mantidos nessas paisagens agrícolas muito fragmentadas, gerando subsídios para ações de conservação e restauração. Nesse sentido, as perguntas norteadoras deste estudo foram: 1) o conhecimento do componente regenerante de remanescentes florestais inseridos em matrizes agrícolas muito fragmentadas permite avaliar a perpetuação dos mesmos ao longo do tempo? 2) quais fatores, de qualidade de hábitat ou de estrutura da paisagem, exercem maior influência sobre composição, densidade e riqueza de espécies no componente regenerante desses remanescentes florestais? Para isso, foi comparada a riqueza, diversidade e composição de espécies entre o componente regenerante (altura >1,0 m e DAS< 5 cm) e arbóreo (DAS> 5 cm) de 18 fragmentos de florestas nativas do noroeste de São Paulo. Em seguida, foi analisada a relação entre a qualidade do hábitat (soma de bases do solo, teor de argila do solo e frequência de incêndio) e estrutura da paisagem (conectividade, isolamento e tamanho total do fragmento) com os valores descritivos do componente regenerante. Foram registrados no componente regenerante 5.989 indivíduos e 207 espécies, o que equivale a uma média de 4968±3584 ind.ha-1 e 33±14 espécies por fragmento. As famílias mais ricas foram Fabaceae (28 espécies), Myrtaceae (25), Rubiaceae (21) e os gêneros foram Eugenia (12), Ocotea (6), Campomanesia (5) e Psychotria (5). Comparado ao componente arbóreo, o componente regenerante apresentou significativamente menor riqueza e diversidade &alpha;, pois 71% das espécies do componente arbóreo não foram registradas na regeneração natural. Porém, ambos componentes apresentaram composição florística significativamente correlacionada. Com relação à diversidade &beta;, em média, o componente regenerante apresentou valor significativamente maior entre os fragmentos. A qualidade de habitat foi mais importante para explicar a estrutura e riqueza da comunidade regenerante. Frequência de incêndio contribuiu negativamente para a densidade total comunidade e de indivíduos zoocóricos, clímaces de sub-bosque e de dossel, assim como para a riqueza de espécies zoocóricas, pioneiras e colonizadoras. A riqueza de especialistas de florestas apresentou relação positiva com a soma de bases enquanto para a riqueza e densidade de generalistas a relação foi negativa. Soma de bases e teor de argila no solo foram as variáveis mais relacionadas com a composição florística da comunidade regenerante. Dentre as variáveis de paisagem, conectividade relacionou-se negativamente com a densidade de espécies generalistas enquanto área do fragmento apresentou relação positiva com a densidade de zoocóricas com propágulos de tamanho médio. Portanto, a regeneração natural representou um subconjunto de espécies do componente arbóreo com menor diversidade, riqueza e número de espécies compartilhadas entre os fragmentos e por isso seriam necessárias ações de manejo adaptativo para garantir a perpetuação dos remanescentes florestais nessas paisagens muito fragmentadas. Frequência de incêndios foi o principal fator comprometedor da perpetuação da biodiversidade e a importância do gradiente edáfico para composição de espécies dos remanescentes florestais da região foi confirmada. / The northwestern São Paulo, a transition area between the Atlantic Forest and Cerrado, is one of the most fragmented region of the state. Investigating the sapling community of forest communities would be possible understanding how species diversity and ecological processes are maintained in this kind of landscape and therefore it would help creating subsides for forest restoration. For this reason, the questions of this research were: 1) Does the survey of sapling community of forest remnants in highly fragmented agricultural landscape allows assessing their self-perpetuating capacity? 2) Which factors of habitat quality or landscape structure exerts greater influence on the species composition, density and species-richness of the sapling community of these forest remnants? Thus, it was assessed the sapling community (height >one, 0 m and DSH< 5,0 cm) density and compared the observed and the relative species-richness of functional groups, &alpha; and &beta; diversity and species composition to the tree community (DSH> 5,0 cm) in the same forest remnant. After that, was assessed the influence of habitat quality (soil sum of bases, soil clay content, fire frequency) and landscape structure (functional connectivity, isolation and total size of these forest remnants) on the descriptive values of sapling communities. Overall, the sapling community showed 5.989 individuals and 207 species that represent on average 4968±3584 ind.ha-1 and 33±14 species for forest fragments. The botanic families with higher species-richness were Fabaceae (28 species), Myrtaceae (25), Rubiaceae (21) and genera were Eugenia (12), Ocotea (6), Campomanesia (5) e Psychotria (5).Compared to the tree community, the sapling community had significantly smaller species-richness (observed and estimated) and &alpha; diversity, because 71 % of species from the tree community did not occur in sapling community. However, both communities had species composition significantly correlated, the sapling communities showed significantly higher &beta; diversity than trees communities. The habitat quality were more important to explain the density, species-richness and species composition of the sapling communities. Fire frequency contributed negatively to species-richness of zoochorous species, pioneer species and colonizers group (species found only at sapling community) and to the sapling density of zoochorous species, shade-tolerant canopy species and shade-tolerant understory species. The species-richness of forest-specialist species was positively related to the soil sum of bases but to the sapling density and species-richness of generalist species was found the opposite relation. Similarly, sum of base and clay content were the variables most related to the species composition of sapling community. Functional connectivity and the total area of the forests fragments explained only the density of generalist and zoochorous medium-seeded species, but with relatively smaller importance than the habitat quality variables. Thus, the sapling community of these forest remnants represented a subset of the tree community but with significant smaller diversity, species richness and number of common species among fragments and then adaptive management efforts is needed to assist long-term biodiversity persistence in forests fragments in highly fragmented agricultural landscape. Frequent fires was the main factor affecting negatively the biodiversity perpetuation and the importance of an edaphic gradient to species composition of forests remnants in the region was validated.

Despite growing scrutiny of Environmental Impact Assessment (EIA) in Canada and worldwide, the follow-up and monitoring component remains under practiced, leaving EIA decision-makers and practitioners with little understanding of the accuracy of impact predictions made and the effectiveness of mitigation measures developed during the EIA project-planning phase. The Minister’s Expert Panel further highlighted the importance of enhancing follow-up and monitoring during the recent review of EIA processes in Canada. The research identifies six leading edge practices for next generation EIA follow-up and monitoring: public and Indigenous participation, continuous learning, clear roles and responsibilities, independent oversight, adaptive management and traditional knowledge. Approaches to implement those practices in a Canadian context are explored and supported by guidance that captures the learning potential of EIA follow-up and monitoring. The six practices are intended as a package and are presented with practical guidance for proponents, regulators, consultants and others involved in EIA. / May 2017

En Europe, la présence de grands carnivores dans des paysages anthropisés entraîne une forte compétition avec l'homme et alimente d'importantes polémiques concernant leur protection légale. La perception antagoniste de ces espèces à la fois emblématiques pour certains et sources de conflits pour d'autres, rend la gestion de leurs populations très délicate. Depuis la recolonisation spontanée du loup (Canis lupus) dans les Alpes françaises au début des années 1990, la population s'est accrue numériquement et spatialement. Parallèlement, les dégâts occasionnés par le loup sur la filière élevage ont suivi la même tendance. L'Etat met en place aujourd'hui un contrôle raisonné de la population, sous réserve que les objectifs de conservation, exigés par la Directive Habitat, soient respectés. En s'inspirant du cas d'étude du loup en France, nous proposons dans cette thèse un cadre de prise de décision structurée adapté pour la gestion et la conservation d'espèces rares et difficilement observables, protégées par des accords législatifs mais qui, dans un contexte social conflictuel, peuvent être régulées. La modélisation séquentielle du processus décisionnel s'est déroulée dans un contexte de forte incertitude selon plusieurs étapes : 1) appréhender les objectifs de conservation et/ou contrôle du loup en France pour les formaliser sous forme mathématique via une fonction d'utilité, 2) suivre la population par une méthode non-invasive pour définir des indicateurs de gestion fiables et évaluer le statut de conservation de la population, 3) coupler les mesures létales adoptées actuellement à un modèle démographique décrivant la dynamique du loup et intégrant sa structure sociale, 4) et déterminer la décision. Cette dernière étape est réalisée à l'aide d'une méthode d'optimisation qui calcule la stratégie optimale de gestion en fonction de la structure sociale de la population et des différentes sources d'incertitude accumulées à chaque étape du processus décisionnel. Nous avons choisi comme indicateur de gestion le taux de croissance, à partir duquel nous avons défini l'utilité. Cet indicateur était robuste à l'incertitude d'échantillonnage émergeant de la détection partielle et hétérogène des individus. Des analyses de sensibilité de la décision ont montré une forte influence de la fonction d'utilité sur la stratégie optimale, soulignant ainsi l'importance de définir correctement les objectifs. Nous avons également montré que la stratégie optimale était sensible aux variations des paramètres démographiques, montrant ainsi l'intérêt des méthodes de capture-marquage-recapture pour les estimer correctement. Nous discutons enfin de l'extension de notre approche à un cadre décisionnel de gestion adaptative pour traiter des problèmes de conservation dans un contexte conflictuel. / Large carnivore management in Europe is controversial because of conflictive objectives arising from the legal protection of threatened species vs. the possible necessity of culling individuals to prevent severe damages on human activities. Since the wolf recovery in the French Alps in the early 90's, the population has been numerically and spatially increasing. In parallel, livestock depredations have been following the same trend. As an EU member state, France is bound to the European Habitat Directive, which provides full protection of wolf populations and their habitat. Nevertheless, derogatory killings are allowed for individuals causing problems on livestock and some lethal control is now incorporated into the national management plan, as long as the population growth and its distribution range are not being threatened. Illustrating with the case study of the wolf in France, my dissertation proposes a structured decision making framework for the management and the conservation of elusive species that are legally protected but, in a conflictive context, are subject to population control. The sequential modeling of our decision process occurred in the following steps: 1) define the multiple objectives and formulate them in terms of a utility function, 2) monitor the population through a non-invasive approach in order to define the population conservation status, 3) build a demographic model to predict the consequences of harvesting on population dynamics and social structure, 4) obtain optimal state-dependent decisions. The last step is done with stochastic dynamic programming (SDP), acknowledged to be one of the most useful optimization methods in decision making. We provide an optimal solution for wolf management that gives the highest chance of meeting objectives, defined on population growth rate. This demographic indicator was found to be robust to sampling uncertainty arising from partial and heterogeneous detection of individuals. We ran decision sensibility analyses and found a strong effect of the utility function on the optimal strategy, highlighting the importance of defining explicit objectives. We also found that the optimal strategy was sensitive to demographic parameters, which demonstrate the general need of using solid statistical approaches to estimate them properly. This structured decision making framework can further be extended to adaptive management, acknowledged as being a convenient framework for wildlife management.

The research, presented here, is about the collaborative governance and adaptive management in coastal planning efforts of Louisiana. Fundamental conflict, between the idea of environmental conservation and developmental growth, has always existed in the coastal regions. The presence of the large number of environmental laws, at various levels of government and their different management objectives for utilization of coastal resources, requires study of intergovernmental relationship. Taking Plaquemines Parish as a case in point, this thesis will, therefore, review the critical restoration plans for intergovernmental coordination and conflicts. It will also provide recommendations, for elected representatives and policy makers, with an aim to promote collaborative governance and improve adaptive management of coastal resources.

In the past two decades, there has been a growing consensus regarding the inadequacies of the existing environmental policy regime and the need for reform to address complex, cross-jurisdictional sustainability challenges, such as nonpoint source pollution. Reform theory has focused on the need for more integrated, collaborative, adaptive, and results-oriented environmental management, while empirical studies have highlighted the wide implementation gap due to an array of institutional obstacles. Key principles and challenges of these four reform dimensions were synthesized in this study and used to assess implementation of the watershed approach by the U.S. Environmental Protection Agency and states since the early 1990s. This dissertation used a qualitative multiple case study design to examine the evolving watershed reform strategies of North Carolina, Georgia, and Kentucky, drawing on extensive document review and interviews with over 50 agency managers. Using an environmental federalism framework adapted from Scheberle (2004), the study explored the role of the national and regional EPA policy context, as well as state-level factors, in helping to shape the watershed approach strategies in the state cases. The research revealed that while EPA provided important initial support of state watershed management, its fragmented, output-driven program management continues to be a barrier to reform. EPA Region 4’s recent reform efforts demonstrate that regional offices can take critical steps to incorporate the watershed approach into internal agency management processes and external relations with states and stakeholders, but these changes often go against the grain of agency culture and norms. State agencies have made progress but face similar reform challenges, and their strategies are further shaped by important policy drivers, constraints, and resource limitations at the state level. More substantial investment is needed by EPA and states to: strengthen internal and external watershed coordination roles and forums; support collaborative stakeholder initiatives more fully where needed; and manage adaptively and accountably towards collectively defined watershed outcome targets.

<p>The Table Mountain Group (TMG) Formation is the lowest member of the Cape Supergroup which consists of sediments deposited from early Ordovician to early Carboniferous times, approximately between 500 and 340 million years ago. The Table Mountain Group (TMG) aquifer system is&nbsp / exposed along the west and south coasts of South Africa. It is a regional fractured rock aquifer that has become a major source of bulk water supply to&nbsp / meet the agricultural and urban water requirements of the Western and Eastern Cape Provinces of South Africa. The TMG aquifer system comprises of an approximately 4000 m thick sequence of quartz arenite and minor shale layers deposited in a shallow, but extensive, predominantly eastwest striking&nbsp / asin, changing to a northwest orientation at the west coast. The medium to coarse grain size and relative purity of some of the quartz arenites,&nbsp / together with their well indurated nature and fracturing due to folding and faulting in the fold belt, enhance both the quality of the groundwater and its&nbsp / exploitation potential for agricultural and domestic water supply purposes and its hot springs for recreation. The region is also home to some unique&nbsp / and indigenous floral species (fynbos) of worldwide importance. These and other groundwater dependent vegetation are found on the series of&nbsp / mountains, mountain slopes and valleys in the Cape Peninsula. The hydrogeology of the TMG consists of intermontane and coastal domains which&nbsp / have different properties but are interconnected. The former is characterized by direct recharge from rain and snow melt, deep groundwater circulation with hot springs and low conductivity groundwater. The coastal domain is characterized by shallow groundwater occurrence usually with moderate to&nbsp / poor quality, indirect recharge from rainfall of shallow circulation and where springs occur they are usually cold. The sustainable utilization of the TMG&nbsp / aquifer addressed the issues of the groundwater flow dynamics, recharge and discharge to and from the aquifer / challenges of climate change and climate variability and their potential impact on the aquifer system. The concept of safe yield, recharge and the capture principle and the integration of&nbsp / sustainable yield provided the basis for sustainable utilization with the adaptive management approach. Methodology used included the evaluation of&nbsp / recharge methods and estimates in the TMG aquifer and a GIS based water balance recharge estimation. The evaluation of natural discharges and&nbsp / artificial abstractions from the TMG aquifer system as well as its potential for future development. The Mann-Kendal trend analysis was used to test historical and present records of temperature and rainfall for significant trends as indication for climate variability and change. The determination of&nbsp / variability index of rainfall and standard precipitation index were additional analyses to investigate variability. The use of a case study from the Klein&nbsp / (Little) Karoo Rural Water Supply Scheme (KKRWSS) within the TMG study area was a test case to assess the sustainable utilization of TMG aquifers.&nbsp / Results show that recharge varies in time and space between 1% and 55% of MAP as a result of different hydrostratigraphic units of the TMG based on&nbsp / geology, hydrology, climate, soil, vegetation and landuse patterns however, the average recharge is from 1% to 5% of MAP. The TMG receives recharge&nbsp / mainly through its 37,000 km2 of outcrop largely exposed on mountainous terrain. Natural discharges from the TMG include 11 thermal and numerous&nbsp / cold spring discharges, baseflow to streams and reservoirs, and seepage to the ocean. Results from this study also show increasing temperature&nbsp / trend over the years while rainfall trend generally&nbsp / remain unchanged in the study area. Rainfall variability persists hence the potential for floodsand droughts in the region remain. Global and Regional Models predict about 10% to 25% reduction in rainfall and increase in variability in future. Impacts of&nbsp / his change in climate will affect the different types of aquifers in various ways. Increase in temperature and reduction in rainfall will increase&nbsp / evapotranspiration, reduce surface flows and eventually reduce shallow aquifer resources. Coastal aquifers risk upsurge in salinisation from sea level&nbsp / rise and increase in abstractions from dwindling surface water resources. While floods increase the risk of contamination to shallow aquifers droughts&nbsp / put pressure on all aquifers especially deep aquifers which are considered to be more reliable due to the fact that they are far removed from surface conditions. Future population growth and increase in freshwater demand will put more pressure on groundwater. Recharge to groundwater have been&nbsp / over-estimated in certain areas in the past leading to high abstraction rates from boreholes causing extensive groundwater storage depletion evident by high decline in groundwater levels in these areas and hampering sustainable management of the aquifer resources. Over-abstraction have resulted in&nbsp / loss of stream flow and baseflow reduction to streams during summer, complete loss of springs and reduction of flow to others. Flow to wetlands,&nbsp / riparian vegetation, and sometimes loss and shifts in dependent ecosystems have also resulted from over-abstraction. Sustainability has spatial and&nbsp / temporal implications due to changing climate and demand. The study recommends adaptive management practices in which several factors are&nbsp / considered in managing groundwater together with surface water resources in order to maintain ecological and environmental integrity. The KKRWSS&nbsp / and other groundwater supply schemes in the Western and Eastern Cape Provinces demonstrate the huge potential of the TMG to provide freshwatersupply for domestic and irrigation water needs however, the huge decline in groundwater levels due to over-abstraction in the KKRWSS and&nbsp / other groundwater schemes underscores the need for sustainable utilization of the TMG groundwater resources for present and future generations with&nbsp / minimal impacts on the quality, dependent hydrological and ecosystems as well as the environment.</p>