Role of Storm Erosion Potential and Beach Morphology in Controlling Dune Erosion

Coastal erosion is controlled by two sets of factors, one related to storm intensity and the other related to a location’s vulnerability. This study investigated the role of each set in controlling dune erosion based on data compiled for eighteen historical events in New Jersey. Here, storm intensity was characterized by the Storm Erosion Index (SEI) and Peak Erosion Intensity (PEI), factors used to describe a storm’s cumulative erosion potential and maximum erosive power, respectively. In this study, a direct relationship between these parameters, beach morphology characteristics, and expected dune response was established through a classification tree ensemble. Of the seven input parameters, PEI was the most important, indicating that peak storm conditions with time scales on the order of hours were the most critical in predicting dune impacts. Results suggested that PEI, alone, was successful in distinguishing between storms most likely to result in no impacts (PEI < 69) and those likely to result in some (PEI > 102), regardless of beach condition. For intensities in between, where no consistent behavior was observed, beach conditions must be considered. Because of the propensity for beach conditions to change over short spatial scales, it is important to predict impacts on a local scale. This study established a model with the computational effectiveness to provide such predictions.

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The modulating role of traits on the biogeographic dynamics of chondrichthyans from the Neogene to the present

Paleobiology ◽

10.1017/pab.2018.7 ◽

2018 ◽

Vol 44 (2) ◽

pp. 251-262 ◽

Cited By ~ 8

Author(s):

Jaime A. Villafaña ◽

Marcelo M. Rivadeneira

Keyword(s):

Life History ◽

Spatial Scales ◽

Regional Scale ◽

Local Scale ◽

Range Shifts ◽

Similar Proportion ◽

Random Forest Models ◽

Body Sizes ◽

Exogenous Factors

AbstractThe environmental transformations that occurred during the Neogene had profound effects on spatiotemporal biodiversity patterns, yet the modulating role of traits (i.e., physiological, ecological, and life-history traits) remains little understood. We tested this idea using the Neogene fossil record of chondrichthyans along the temperate Pacific coast of South America (TPSA). Information for georeferenced occurrences and ecological and life-history information of 38 chondrichthyan fossil genera in 42 Neogene sites was collected. Global georeferenced records were used to estimate present-day biogeographic distributions of the genera and to characterize the range of oceanographic conditions in which each genus lives as a proxy of their realized niche. Biogeographic range shifts (Neogene–present) were evaluated at regional and local scales. The role of traits as drivers of different range dynamics was evaluated using random forest models. The magnitude and direction of biogeographic range shifts were different at both spatial scales. At a regional scale, 34% of genera contracted their ranges, disappearing from the TPSA. At a local scale, a similar proportion of genera expanded and contracted their southern endpoints of distribution. The models showed a high precision at both spatial scales of analyses, but the relative importance of predictor variables differed. At a regional scale, disappearing genera tended to have a higher tolerance to salinity, lower sea surface temperature (SST) range, and smaller body sizes. At a local scale, genera contracting their ranges tended to live at greater depths, tolerate lower levels of primary productivity, and show a reduced tolerance to higher and lower SST ranges. The magnitude and direction of the changes in the range distribution were scale dependent and variable across the genera. Hence, multiple environmental exogenous factors interacted with taxon traits during the Neogene, creating a mosaic of biogeographic dynamics.

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The Relative Effects of Local and Landscape Characteristics of Hedgerows on Bats

Diversity ◽

10.3390/d10030072 ◽

2018 ◽

Vol 10 (3) ◽

pp. 72 ◽

Cited By ~ 9

Author(s):

Aurélie Lacoeuilhe ◽

Nathalie Machon ◽

Jean-François Julien ◽

Christian Kerbiriou

Keyword(s):

Spatial Scales ◽

Positive Influence ◽

Local Scale ◽

Agricultural Landscapes ◽

Intensive Agriculture ◽

Acoustic Survey ◽

Bat Activity ◽

Landscape Characteristics ◽

Landscape Scales

The role of hedgerows in maintaining biodiversity in areas of intensive agriculture is well known, particularly for bats. However, few studies have addressed the importance of the intrinsic characteristics of hedgerows for bats and disentangled the relative effects of local and landscape characteristics of hedgerows on bat activity. In an acoustic survey, we assessed bat activity by recording bat calls using detectors and manually verified all calls using spectrogram analysis. The parameters used to determine local hedgerow structures were the length of the line of trees, of shrub hedgerows, of wooded hedgerows without shrubs and of hedgerows including the three strata (tree, shrub and herb) at a local scale. We assessed the influence of hedgerow structure and on bat activity with an approach considering both species and community, comparing two different scales, the local and the landscape. We highlighted the importance of hedgerow characteristics for bats on both the local and landscape scales even though responses differ between species and spatial scales. We found that the presence of trees in hedgerows exerts a generally positive influence on bat activity and that hedgerows with the three strata had lower bat activity than hedgerows with trees. In our study, some bats seemed to prefer agricultural landscapes dominated by wooded hedgerows and, on the local scale, hedgerows that include trees with little diversified among strata, except for gleaning species. Our study shows that in terms of hedgerow management, conservation efforts must be designed and undertaken on both the local and landscape scales.

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POLÍTICAS DE ESCALA E A CONFORMAÇÃO DE ESTRATÉGIAS-REDE DAS AÇÕES COLETIVAS NO ESPAÇO SISALEIRO DA BAHIA

GEOgraphia ◽

10.22409/geographia.v19i41.1095 ◽

2018 ◽

Vol 19 (41) ◽

pp. 39

Author(s):

Agripino Souza Coelho Neto

Keyword(s):

Political Action ◽

Spatial Scales ◽

Spatial Behavior ◽

Collective Actions ◽

Collective Behaviors ◽

Rural Workers ◽

Scale Levels ◽

Scale Network ◽

Comme Point

Resumo: O presente texto pretende analisar o papel das ações coletivas (associações, cooperativas e sindicatos de agricultores) no acionamento e na ativação das escalas geográficas para o desenvolvimento de suas atividades. O estudo foi realizado no Espaço Sisaleiro da Bahia (Brasil), onde um conjunto significativo de associações e cooperativas de agricultores e sindicatos de trabalhadores rurais tem se organizado em torno das escalas espaciais para viabilizar sua ação político-institucional e econômico-produtiva. A ação desses coletivos organizados em rede tem permitido a conformação e o fortalecimento de novas escalas de ação política, como no caso da criação do conselho territorial para viabilização da implantação de políticas de governo. Cooperativas, associações e sindicatos se apoiam nas escalas para compor organizações em diferentes níveis escalares (escala local, escala regional, escala do estado federado e escala nacional), buscando fortalecer seus propósitos e ampliar seu poder de barganha e influência. Analisando o comportamento espacial dessas variadas modalidades de ações coletivas, é possível considerar que elas desenvolvem políticas de escala, ou seja, a escala passa a significar muito mais que uma categoria de análise, mas se torna uma categoria da prática social e política. Nesse sentido, parte-se do pressuposto de que os grupos humanos produzem e tornam efetivas suas próprias escalas visando a alcançar suas metas e organizar seus comportamentos coletivos. Palavras-chave: Escala. Rede. Cooperativismo. Associativismo. Sindicalismo. Espaço Sisaleiro da Bahia. SCALE POLICIES AND THE DEVELOPMENT OF NETWORK STRATEGIES OF COLLECTIVE ACTIONS IN THE SISAL REGION OF BAHIA (BRAZIL)Abstract: This paper aims to analyze the role of collective initiatives of associations, cooperatives and farmers’ unions in the mobilization and activation of geographical scales for the development of their activities. The study was conducted in the Sisal Region of Bahia (Brazil), where a significant number of farmers associations and cooperatives and rural workers’ unions have been organizing their actions around spatial scales to enable their political-institutional and economic-productive influence. The gathering and action of these organized groups in a network have allowed the establishment and strengthening of new scales of political action, as seem in the case of the creation of a territorial council to facilitate the implementation of government policies. Cooperatives, associations, and unions rely on scales to form organizations at different scale levels (local, regional, federal and national scales), seeking to strengthen their performance and increase their bargaining power and influence. After analyzing the spatial behavior of these various forms of collective actions, it’s reasonable to say that they develop scale policies, which means the scale becomes more than a category of analysis, but also a category of social and political practice. In this sense, it’s assumed that human groups produce and utilize the scales in order to reach their goals and organize their own collective behaviors. Keywords: Scale. Network. Cooperativism. Associativism. Syndicalism. Sisal Region of Bahia. POLITIQUES D’ÉCHELLE ET FORMATION DES STRATÉGIES-RÉSEAU DES ACTIONS COLLECTIVES DANS LA RÉGION DU SISAL DE L’ÉTAT DE BAHIA Resumé: Cet article analyse le rôle des actions collectives (associations, coopératives et syndicats d’agriculteurs) dans la prise en compte et l’utilisation des échelles géographiques pour le développement de leurs activités. L’étude a été menée dans la région du sisal à Bahia (Brésil), où un ensemble important d’associations et de coopératives d’agriculteurs et de syndicats de travailleurs ruraux se sont organisés autour d’échelles spatiales pour que puisse être mise en place leur action politique et institutionnelle, économique et productive. L’action de ces groupements organisés en réseaux a permis la conformation et le renforcement de nouvelles échelles d’action politique, comme lors de la création du conseil territorial, pour permettre la mise en œuvre des politiques gouvernementales. Les coopératives, les associations et les syndicats prennent les échelles comme point de départ pour former des organisations à différents niveaux scalaires (échelle locale, échelle régionale, échelle fédérée et échelle nationale), dans le but de renforcer leurs objectifs et d’accroître leur pouvoir de négociation et d’influence. Si nous analysons le comportement spatial de ces diverses formes d’action collective il est possible de considérer qu’ils développent des politiques d’échelle, à savoir l’échelle vient signifier bien plus qu’une catégorie d’analyse, puisqu’elle devient une catégorie de la pratique sociale et politique. En ce sens, on suppose que les groupes humains produisent et rendent efficaces leurs propres échelles pour atteindre leurs objectifs et organiser leurs comportements collectifs. Mots-clés: Échelle. Réseau. Coopérativisme. Associations. Syndicalisme. Région du sisal de l’État de Bahia.

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EXPLORING THE ROLE OF GROUNDWATER STORAGE IN WATERSHED VARIABILITY ACROSS SPATIAL SCALES

10.1130/abs/2020am-359524 ◽

2020 ◽

Author(s):

Laura Condon ◽

Keyword(s):

Spatial Scales ◽

Groundwater Storage

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The effects of armed conflict on forest cover changes across temporal and spatial scales in the Colombian Amazon

Regional Environmental Change ◽

10.1007/s10113-021-01770-6 ◽

2021 ◽

Vol 21 (3) ◽

Author(s):

Oscar V. Bautista-Cespedes ◽

Louise Willemen ◽

Augusto Castro-Nunez ◽

Thomas A. Groen

Keyword(s):

Armed Conflict ◽

Forest Cover ◽

Spatial Scales ◽

Armed Forces ◽

Peace Negotiations ◽

Post Conflict ◽

Forest Cover Changes ◽

The Government ◽

Colombian Amazon

AbstractThe Amazon rainforest covers roughly 40% of Colombia’s territory and has important global ecological functions. For more than 50 years, an internal war in the country has shaped this region. Peace negotiations between the government and the Revolutionary Armed Forces of Colombia (FARC) initiated in 2012 resulted in a progressive de-escalation of violence and a complete ceasefire in 2016. This study explores the role of different deforestation drivers including armed conflict variables, in explaining deforestation for three periods between 2001 and 2015. Iterative regression analyses were carried out for two spatial extents: the entire Colombian Amazon and a subset area which was most affected by deforestation. The results show that conflict variables have positive relationships with deforestation; yet, they are not among the main variables explaining deforestation. Accessibility and biophysical variables explain more variation. Nevertheless, conflict variables show divergent influence on deforestation depending on the period and scale of analysis. Based on these results, we develop deforestation risk maps to inform the design of forest conservation efforts in the post-conflict period.

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Arthropod community structure in pastures of an island archipelago (Azores): looking for local–regional species richness patterns at fine-scales

Bulletin of Entomological Research ◽

10.1079/ber2004289 ◽

2004 ◽

Vol 94 (2) ◽

pp. 111-121 ◽

Cited By ~ 22

Author(s):

P.A.V. Borges ◽

V.K. Brown

Keyword(s):

Species Richness ◽

Regional Scale ◽

Local Scale ◽

Local Species Richness ◽

Β Diversity ◽

Arthropod Species ◽

Α Diversity ◽

Local Species ◽

Richness Patterns

AbstractThe arthropod species richness of pastures in three Azorean islands was used to examine the relationship between local and regional species richness over two years. Two groups of arthropods, spiders and sucking insects, representing two functionally different but common groups of pasture invertebrates were investigated. The local–regional species richness relationship was assessed over relatively fine scales: quadrats (= local scale) and within pastures (= regional scale). Mean plot species richness was used as a measure of local species richness (= α diversity) and regional species richness was estimated at the pasture level (= γ diversity) with the ‘first-order-Jackknife’ estimator. Three related issues were addressed: (i) the role of estimated regional species richness and variables operating at the local scale (vegetation structure and diversity) in determining local species richness; (ii) quantification of the relative contributions of α and β diversity to regional diversity using additive partitioning; and (iii) the occurrence of consistent patterns in different years by analysing independently between-year data. Species assemblages of spiders were saturated at the local scale (similar local species richness and increasing β-diversity in richer regions) and were more dependent on vegetational structure than regional species richness. Sucking insect herbivores, by contrast, exhibited a linear relationship between local and regional species richness, consistent with the proportional sampling model. The patterns were consistent between years. These results imply that for spiders local processes are important, with assemblages in a particular patch being constrained by habitat structure. In contrast, for sucking insects, local processes may be insignificant in structuring communities.

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Landscape structure effects on forest plant diversity at local scale: Exploring the role of spatial extent

Ecological Complexity ◽

10.1016/j.ecocom.2014.12.004 ◽

2015 ◽

Vol 21 ◽

pp. 44-52 ◽

Cited By ~ 23

Author(s):

Valerio Amici ◽

Duccio Rocchini ◽

Goffredo Filibeck ◽

Giovanni Bacaro ◽

Elisa Santi ◽

...

Keyword(s):

Plant Diversity ◽

Landscape Structure ◽

Local Scale ◽

Spatial Extent

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Behaviour in flow: perspectives on the distribution and dispersion of meroplanktonic larvae in the water column

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f00-159 ◽

2001 ◽

Vol 58 (1) ◽

pp. 86-98 ◽

Cited By ~ 88

Author(s):

Anna Metaxas

Keyword(s):

Water Column ◽

Turbulent Flows ◽

Larval Dispersal ◽

Spatial Scales ◽

Fluid Motion ◽

Benthic Boundary Layer ◽

Larval Distribution ◽

Physical Measurements ◽

Marine Benthic Invertebrates

For marine benthic invertebrates with meroplanktonic larvae, the relative importance of hydrodynamics and swimming behaviour in determining larval dispersal in the water column, particularly at small spatial scales, has not been determined. In the field, larval aggregations recorded at physical and biological discontinuities in the water column were attributed to hydrodynamics. Similar aggregations obtained in the absence of flow in the laboratory indicate a potentially significant role of behaviour. At large spatial scales, larval distribution in the plankton is mainly regulated by horizontal advection. However, the ability of larvae to behaviourally regulate their position at scales of micrometres to metres when exposed to turbulent fluid motion in the water column, as evidenced in the benthic boundary layer, is unknown. Evaluation of swimming in turbulent flows in the water column is an intriguing area of research, which involves several constraints. In the field, quantification of behaviour is limited by low success in tracking larvae and lack of appropriate observational tools. In the laboratory, the generation and quantification of flow regimes that are representative of those in the field remains a challenge. An approach that integrates biological and physical measurements within realistic ranges is necessary to advance our understanding of larval dispersal.

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