119 research outputs found

    Common right and enclosure in eighteenth-century Northamptonshire

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    All occupiers of open field land, and some occupiers of cottages, enjoyed common right of pasture over the open fields and commonable places of a parish; even those with very small holdings could use common pasture; and in royal forest, fenland parishes, and others with sizeable wastes, landless commoners collected fuel wood, furze, browse and much more. Common of pasture was a critical support of the small occupiers' economy. Its value was maintained by a comprehensive communal regulation of the use of the right, and by apparently effective enforcement of field orders. At enclosure common rights were extinguished - although some part of the old economy survived in newly enclosed forest and fen parishes lying near unenclosed common pastures. In many parishes two thirds of all commoners sold some or all of their land, or left their rented holdings; only half as many left their lands in adjacent open field parishes at the same time. Small owners -old their lands in greater numbers than any other group. Thus opposition to enclosure arose for two reasons: the loss of common right and the loss of land. Opposition in Parliament was voiced in counter-petitions and at the report stage in a majority of successful enclosure Bills. Unlawful opposition in the form of riotous destruction of posts and rails, and more clandestine activity, was more widespread in Northamptonshire than has been thought hitherto; but existing records cannot reveal its full extent. Finally, the enclosure of open fields, and the loss of common rights over waste, woods and permanent commons, closed up the countryside to all but individual owners of land. And for the landless it replaced an economy partially based on rights over all the land with one more dependent on privileges and benevolence

    Towards a Process Domainā€Sensitive Substrate Habitat Model for Sea Lampreys in Michigan Rivers

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    Habitat mapping is a common and often useful tool in the ecological management of rivers. The complex nature of fluvial processes, however, makes it difficult to predict the reachā€scale distribution of substrate habitat from landscapeā€scale covariates. An option is to identify and partition a data set on boundaries of geomorphic process domains, within which the globally complex relationships between landscape, climate, and instream habitat may potentially be approximated by a simpler model. In this study, we used regression trees as a machine learning method for partitioning and identifying useful strata in a geographically extensive substrate habitat model for larvae of the sea lamprey Petromyzon marinus, an invasive and economically harmful species in the Laurentian Great Lakes. We used field survey data from over 5,000 substrate habitat transects collected in 43 watersheds of the Lower Peninsula of Michigan, and we created a geographic database of geographical information systemsā€derived covariates that represent the principal geomorphic influences on substrate habitat. We created three trees in which tree splits delineated (1) spatially contiguous units, (2) noncontiguous units defined by values of the covariates, and (3) both contiguous and noncontiguous units. The adjusted R2 values of the three trees were 0.30, 0.30, and 0.32, respectively, and all three trees outperformed a single model fitted to the entire data set and a set of models fitted to each watershed individually. The trees identified useful stratifications of Michiganā€™s Lower Peninsula, important geomorphic influences on substrate habitat, and variation in the influence of geomorphic processes on substrate habitat across our study region. Conservation and management applications of our model predictions and treeā€based stratifications include sea lamprey population modeling, habitat survey design, and evaluation of dam removal.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141668/1/tafs0313.pd

    Prioritizing ecological restoration among sites in multiā€stressor landscapes

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    Most ecosystems are impacted by multiple local and longā€distance stressors, many of which interact in complex ways. We present a framework for prioritizing ecological restoration efforts among sites in multiā€stressor landscapes. Using a simple model, we show that both the economic and sociopolitical costs of restoration will typically be lower at sites with a relatively small number of severe problems than at sites with numerous lesser problems. Based on these results, we propose using cumulative stress and evenness of stressor impact as complementary indices that together reflect key challenges of restoring a site to improved condition. To illustrate this approach, we analyze stressor evenness across the worldā€™s rivers and the Laurentian Great Lakes. This exploration reveals that evenness and cumulative stress are decoupled, enabling selection of sites where remediating a modest number of highā€intensity stressors could substantially reduce cumulative stress. Just as species richness and species evenness are fundamental axes of biological diversity, we argue that cumulative stress and stressor evenness constitute fundamental axes for identifying restoration opportunities in multiā€stressor landscapes. Our results highlight opportunities to boost restoration efficiency through strategic use of multiā€stressor datasets to identify sites that maximize ecological response per stressor remediated. This prioritization framework can also be expanded to account for the feasibility of remediation and the expected societal benefits of restoration projects.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134184/1/eap1346_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134184/2/eap1346.pd

    Prioritizing native migratory fish passage restoration while limiting the spread of invasive species: A case study in the Upper Mississippi River

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    Despite increasing efforts globally to remove dams and construct fish passage structures, broad-scale analyses balancing tradeoffs between cost and habitat gains from these mitigations infrequently consider invasive species. We present an optimization-based approach for prioritizing dam mitigations to restore habitat connectivity for native fish species, while limiting invasive species spread. Our methodology is tested with a case study involving 240 dams in the Upper Mississippi River, USA. We integrate six native migratory fish species distribution models, distributions of two invasive fishes, and estimated costs for dam removal and construction of fish passes. Varying budgets and post-mitigation fish passage rates are analyzed for two scenarios: ā€˜no invasivesā€™ where non-selective mitigations (e.g., dam removal) are used irrespective of potential invasive species habitat gains and ā€˜invasivesā€™ where a mixture of selective (e.g., lift-and-sort fish passage) and non-selective mitigations are deployed to limit invasive species range expansion. To achieve the same overall habitat connectivity gains, we find that prioritizations accounting for invasive species are 3 to 6 times more costly than those that do not. Habitat gains among native fish species were highly variable based on potential habitat overlap with invasive species and post-mitigation passabilities, ranging from 0.4ā€“58.9% (ā€˜invasivesā€™) and 7.9ā€“95.6% (ā€˜no invasivesā€™) for a $50M USD budget. Despite challenges associated with ongoing nonnative fish invasions, opportunities still exist to restore connectivity for native species as indicated by individual dams being frequently selected in both scenarios across varying passabilities and budgets, however increased restoration costs associated with invasive species control indicates the importance of limiting their further spread within the basin. Given tradeoffs in managing for native vs. invasive species in river systems worldwide, our approach demonstrates strategies for identifying a portfolio of candidate barriers that can be investigated further for their potential to enhance native fish habitat connectivity while concurrently limiting invasive species dispersal

    Forests as Commons ā€“ Changing Traditions and Governance in Europe

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    Commons are complex institutions and exist across the world in a wide range of situations regarding locally developed governance and management systems of many different natural resources. For many people commons remain associated with Hardinā€™s theory concerning the ā€œTragedy of the Commonsā€ (1968), in which he assumed that local users of a natural resource are unable to formulate governance and management structures concerning their own choices that took into account the long-term sustainability of the resource itself. As a result, Hardin articulated that the tragedy was that the resource would inevitably become degraded in such situations and that the solution was private or public ownership. However, across Europe many forests have for a very long period of time successfully been managed as commons, just as they have in many other parts of the world. This chapter has three main aims: It will provide an introduction to the various types of commons before going on to link the issue of commons to the traditional forest landscapes of Europe, and it will look at how the role of forests and forest landscapes has changed and how it may change further in the future

    Blockade of the co-inhibitory molecule PD-1 unleashes ILC2-dependent antitumor immunity in melanoma.

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    Group 2 innate lymphoid cells (ILC2s) are essential to maintain tissue homeostasis. In cancer, ILC2s can harbor both pro-tumorigenic and anti-tumorigenic functions, but we know little about their underlying mechanisms or whether they could be clinically relevant or targeted to improve patient outcomes. Here, we found that high ILC2 infiltration in human melanoma was associated with a good clinical prognosis. ILC2s are critical producers of the cytokine granulocyte-macrophage colony-stimulating factor, which coordinates the recruitment and activation of eosinophils to enhance antitumor responses. Tumor-infiltrating ILC2s expressed programmed cell death protein-1, which limited their intratumoral accumulation, proliferation and antitumor effector functions. This inhibition could be overcome in vivo by combining interleukin-33-driven ILC2 activation with programmed cell death protein-1 blockade to significantly increase antitumor responses. Together, our results identified ILC2s as a critical immune cell type involved in melanoma immunity and revealed a potential synergistic approach to harness ILC2 function for antitumor immunotherapies

    River ecosystem conceptual models and nonā€perennial rivers: A critical review

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    Conceptual models underpin river ecosystem research. However, current models focus on continuously flowing rivers and few explicitly address characteristics such as flow cessation and drying. The applicability of existing conceptual models to nonperennial rivers that cease to flow (intermittent rivers and ephemeral streams, IRES) has not been evaluated. We reviewed 18 models, finding that they collectively describe main drivers of biogeochemical and ecological patterns and processes longitudinally (upstream-downstream), laterally (channel-riparian-floodplain), vertically (surface water-groundwater), and temporally across local and landscape scales. However, perennial rivers are longitudinally continuous while IRES are longitudinally discontinuous. Whereas perennial rivers have bidirectional lateral connections between aquatic and terrestrial ecosystems, in IRES, this connection is unidirectional for much of the time, from terrestrial-to-aquatic only. Vertical connectivity between surface and subsurface water occurs bidirectionally and is temporally consistent in perennial rivers. However, in IRES, this exchange is temporally variable, and can become unidirectional during drying or rewetting phases. Finally, drying adds another dimension of flow variation to be considered across temporal and spatial scales in IRES, much as flooding is considered as a temporally and spatially dynamic process in perennial rivers. Here, we focus on ways in which existing models could be modified to accommodate drying as a fundamental process that can alter these patterns and processes across spatial and temporal dimensions in streams. This perspective is needed to support river science and management in our era of rapid global change, including increasing duration, frequency, and occurrence of drying.info:eu-repo/semantics/publishedVersio

    Pet Project or Best Project? Online Decision Support Tools for Prioritizing Barrier Removals in the Great Lakes and Beyond

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    Structures that block movement of fish through river networks are built to serve a variety of societal needs, including transportation, hydroelectric power, and exclusion of exotic species. Due to their abundance, road crossings and dams reduce the amount of habitat available to fish that migrate from the sea or lakes into rivers to breed. The benefits to fish of removing any particular barrier depends on its location within the river network, its passability to fish, and the relative position of other barriers within the network. Balancing the trade-offs between ecological and societal values makes choosing among potential removal projects difficult. To facilitate prioritization of barrier removals, we developed an online decision support tool (DST) with three functions: (1) view existing barriers at various spatial scales; (2) modify information about barriers, including removal costs; and (3) run optimization models to identify portfolios of removals that provide the greatest amount of habitat access for a given budget. A survey of available DSTs addressing barrier removal prioritization indicates that barrier visualization is becoming widespread but few tools allow dynamic calculation of connectivity metrics, scenario analysis, or optimization. Having these additional functions, our DST enables organizations to develop barrier removal priorities based on cost-effectiveness in restoring aquatic connectivity
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