Identifying Linkages among Conceptual Models of Ecosystem Degradation and Restoration: Towards an Integrative Framework

We present an ecological framework for considering ecosystem degradation and restoration, particularly in rangelands and arid environments. The framework is a synthesis of three conceptual models previously developed by several rangeland and restoration ecologists. We focus first on distinctions and connections between structural and functional components of rangeland ecosystems and then on distinctions and connections between biotic and abiotic components of the ecosystem. We next show that the structural/functional and biotic/abiotic distinctions can be integrated with a stepwise, positive feedback model of degradation to help explain degradation processes and restoration approaches. Finally, we relate those concepts to a threshold model of rangeland degradation. By establishing the conceptual links among these different models, this synthesis provides a broader, more integrated framework for thinking about the dynamics involved in rangeland degradation and restoration. We conclude by presenting some approaches to restoration that are motivated by the suite of concepts that are brought together in the framework.     

Toward the Quantification of a Conceptual Framework for Movement Ecology Using Circular Statistical Modeling

To analyze an animal’s movement trajectory, a basic model is required that satisfies the following conditions: the model must have an ecological basis and the parameters used in the model must have ecological interpretations, a broad range of movement patterns can be explained by that model, and equations and probability distributions in the model should be mathematically tractable. Random walk models used in previous studies do not necessarily satisfy these requirements, partly because movement trajectories are often more oriented or tortuous than expected from the models. By improving the modeling for turning angles, this study aims to propose a basic movement model. On the basis of the recently developed circular auto-regressive model, we introduced a new movement model and extended its applicability to capture the asymmetric effects of external factors such as wind. The model was applied to GPS trajectories of a seabird (Calonectris leucomelas) to demonstrate its applicability to various movement patterns and to explain how the model parameters are ecologically interpreted under a general conceptual framework for movement ecology. Although it is based on a simple extension of a generalized linear model to circular variables, the proposed model enables us to evaluate the effects of external factors on movement separately from the animal’s internal state. For example, maximum likelihood estimates and model selection suggested that in one homing flight section, the seabird intended to fly toward the island, but misjudged its navigation and was driven off-course by strong winds, while in the subsequent flight section, the seabird reset the focal direction, navigated the flight under strong wind conditions, and succeeded in approaching the island.     

Biodiversity Resources for Restoration Ecology

Biological resources can be more usefully incorporated into many aspects of restoration ecology. During the planning and design stage, the wide genotypic variation in natural plant populations must be recognized and exploited. This will ensure that genotypes used on a site are best adapted to local conditions and have a greater probability of survivorship than arbitrarily chosen material. Also, certain unusual genotypes can be located using the principles of evolutionary ecology and can be installed in areas with extreme conditions, such as soils contaminated with heavy metals, in areas where rapid colonizing ability (high seed set and/or clonal growth) is particularly advantageous, or where soils are of poor quality. Similarly, where high herbivore pressure is a threat to restoration, genotypes that are well defended, chemically or mechanically, against animal enemies should be selected to initiate the restoration process. The nursery industry can be encouraged to supply an ecologically wider selection of material for restoration, originating from local biological reserves and natural habitats. During the management phase of a restoration, local natural habitats are critical as reservoirs of biological control agents, seed sources for plant species, and members of higher trophic levels and additional plant species needed during succession. Mutualists such as pollinators, seed dispersers, and mycorrhizal fungi are vital to the success of a restoration project, and these must invade from nearby natural habitats or must be deliberately introduced. During the evaluation phase of restoration, local natural areas should be used as templates of community composition and structure from which one measures success. A functioning restoration project will interact biologically with surrounding areas, the exchange of species and genes being particularly important. Analysis of the microbial and invertebrate communities that have invaded the installed plant community may be useful and accurate determinants of ecological function. For these latter stages of the restoration process, the value of preserving local habitat remnants is high and complements their usefulness as a source of ecologically precise material for installation.     

Cultural Identity Among Afghan and Iraqi Traumatized Refugees: Towards a Conceptual Framework for Mental Health Care Professionals

Cultural identity in relation with mental health is of growing interest in the field of transcultural psychiatry. However, there is a need to clarify the concept of cultural identity in order to make it useful in clinical practice. The purpose of this study is to unravel the complexity and many layers of cultural identity, and to assess how stress and acculturation relate to (changes in) cultural identity. As part of a larger study about cultural identity, trauma, and mental health, 85 patients from Afghanistan and Iraq in treatment for trauma-related disorders were interviewed with a Brief Cultural Interview. The interviews were analysed through qualitative data analysis using the procedures of grounded theory. The analysis resulted in three domains of cultural identity: personal identity, ethnic identity and social identity. Within each domain relationships with stress and acculturation were identified. The results offer insight into the intensity of changes in cultural identity, caused by pre-and post-migration stressors and the process of acculturation. Based on the research findings recommendations are formulated to enhance the cultural competency of mental health workers.     

Woodland Restoration in the Western Australian Wheatbelt: A Conceptual Framework Using a State and Transition Model

Woodlands dominated by Eucalyptus spp. in temperate southeastern and southwestern Australia have been extensively cleared for agriculture and are often badly degraded by livestock grazing. This has resulted in the loss of biodiversity and widespread land degradation. The continuing decline of these woodlands has become a concern for the conservation of biodiversity, and there is a growing interest among farmers, land managers, and researchers in developing techniques for restoring them. Currently few scientific guidelines exist for undertaking woodland restoration programs. We use a state and transition model to develop hypotheses on restoration strategies for salmon gum (Eucalyptus salmonophloia) woodlands. We consider that this approach provides a suitable framework for organizing knowledge and identifying areas where further information is needed, and hence provides a useful starting point for a restoration program. The model has the potential to provide a tool for land managers with which they can assess the action and effort needed to undertake woodland restoration in agricultural landscapes.     

A Conceptual Framework for Biology Part II

This essay is part of the seventh yearly presentation of aneducational project of the American Society of Zoologists, Scienceas a Way of Knowing. It is also the second part of a "ConceptualFramework for Biology." Part II begins a discussion of evolutionand deals with an overview of living metazoans and then discussestheir history during the Phanerozoic Eon. Part III will completethe discussion of evolution and then consider "Classification,"Ecology," "Geographic Distribution," "Methods of Science,"and "Science and Human Welfare." The intended readers are thosewho teach the first-year biology courses in colleges and universitiesas well as teachers of the precollege grades.     

A Conceptual Framework for Biology Part I

These essays are part of the sixth yearly presentation of aneducational project of the American Society of Zoologists. Thepurpose is to provide background materials for those who teachthe first-year biology courses in colleges and universities.The Science as a Way of Knowing project emphasizes the conceptualframework of the biological sciences, shows how scientific informationis obtained and validated, and relates science to human concerns.The topic for consideration this year is Cell and MolecularBiology.     

Policy Language in Restoration Ecology

Relating restoration ecology to policy is one of the aims of the Society for Ecological Restoration and its journal Restoration Ecology. As an interdisciplinary team of researchers in both ecological science and political science, we have struggled with how policy‐relevant language is and could be deployed in restoration ecology. Using language in scientific publications that resonates with overarching policy questions may facilitate linkages between researcher investigations and decision‐makers' concerns on all levels. Climate change is the most important environmental problem of our time and to provide policymakers with new relevant knowledge on this problem is of outmost importance. To determine whether or not policy‐specific language was being included in restoration ecology science, we surveyed the field of restoration ecology from 2008 to 2010, identifying 1,029 articles, which we further examined for the inclusion of climate change as a key element of the research. We found that of the 58 articles with “climate change” or “global warming” in the abstract, only 3 identified specific policies relevant to the research results. We believe that restoration ecologists are failing to include themselves in policy formation and implementation of issues such as climate change within journals focused on restoration ecology. We suggest that more explicit reference to policies and terminology recognizable to policymakers might enhance the impact of restoration ecology on decision‐making processes.     

Linking Restoration and Landscape Ecology

Landscape ecology focuses on questions typically addressed over broad spatial scales. A landscape approach embraces spatial heterogeneity, consisting of a number of ecosystems and/or landscape structures of different types, as a central theme. Such studies may aid restoration efforts in a variety of ways, including (1) provision of better guidance for selecting reference sites and establishing project goals and (2) suggestions for appropriate spatial configurations of restored elements to facilitate recruitment of flora/fauna. Likewise, restoration efforts may assist landscape–level studies, given that restored habitats, possessing various patch arrangements or being established among landscapes of varying diversity and conditions of human alteration, can provide extraordinary opportunities for experimentation over a large spatial scale. Restoration studies can facilitate the rate of information gathering for expected changes in natural landscapes for which introduction of landscape elements may be relatively slow. Moreover, data collected from restoration studies can assist in validation of dynamic models of current interest in landscape ecology. We suggest that restoration and landscape ecology have an unexplored mutualistic relationship that could enhance research and application of both disciplines.     

Sink Metabolism: A Conceptual Framework for Analysis

The basic objective of this study was to build a model thatdescribes the physiology of sinks and the process of unloadingassimilates from the phloem. The metabolic steps necessary todescribe a typical sink were obtained from the literature. Severalmethods to describe mathematically these metabolic steps areavailable but they were either too cumbersome and slow or toosimple. This necessitated the development of a new method todescribe multiple enzyme systems. This paper describes the developmentof that method. The method involves a rather simple enzyme analysisof coupled biochemical processes common to most types of sinks.A conceptual framework is presented to provide a basis for furtherquantification of the metabolism of various types of sinks throughtheir development sequence. sink metabolism, model-enzyme kinetics, King-Altman analysis, phloem unloading