Local-Scale Association of Boreal Birds with Clearcuts Does Not Translate to the Landscape Scale

Humus forms are a distinctive morphological indicator of soil organic matter decomposition. The spatial distribution of humus forms depends on environmental factors such as topography, climate and vegetation. In montane and subalpine forests, environmental influences show a high spatial heterogeneity, which is reflected by a high spatial variability of humus forms. This study aims at examining spatial patterns of humus forms and their dependence on the spatial scale in a high mountain forest environment (Val di Sole/Val di Rabbi, Trentino, Italian Alps). On the basis of the distributions of environmental covariates across the study area, we described humus forms at the local scale (six sampling sites), slope scale (60 sampling sites) and landscape scale (30 additional sampling sites). The local variability of humus forms was analyzed with regard to the ground cover type. At the slope and landscape scale, spatial patterns of humus forms were modeled applying random forests and ordinary kriging of the model residuals. The results indicate that the occurrence of the humus form classes Mull, Mullmoder, Moder, Amphi and Eroded Moder generally depends on the topographical position. Local-scale patterns are mostly related to micro-topography (local accumulation and erosion sites) and ground cover, whereas slope-scale patterns are mainly connected with slope exposure and elevation. Patterns at the landscape scale show a rather irregular distribution, as spatial models at this scale do not account for local to slope-scale variations of humus forms. Moreover, models at the slope scale perform distinctly better than at the landscape scale. In conclusion, the results of this study highlight that landscape-scale predictions of humus forms should be accompanied by local- and slope-scale studies in order to enhance the general understanding of humus form patterns.

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Interactions between large herbivores and litter removal by termites across a rainfall gradient in a South African savanna

Journal of Tropical Ecology ◽

10.1017/s0266467411000125 ◽

2011 ◽

Vol 27 (4) ◽

pp. 375-382 ◽

Cited By ~ 9

Author(s):

Robert Buitenwerf ◽

Nicola Stevens ◽

Cleo M. Gosling ◽

T. Michael Anderson ◽

Han Olff

Keyword(s):

Plant Biomass ◽

Spatial Scales ◽

Landscape Scale ◽

Local Scale ◽

Arid Ecosystems ◽

Annual Rainfall ◽

Large Herbivores ◽

Mammalian Herbivores ◽

Litter Removal ◽

Semi Arid

Abstract:Litter-feeding termites influence key aspects of the structure and functioning of semi-arid ecosystems around the world by altering nutrient and material fluxes, affecting primary production, foodweb dynamics and modifying vegetation composition. Understanding these complex effects depends on quantifying spatial heterogeneity in termite foraging activities, yet such information is scarce for semi-arid savannas. Here, the amount of litter that was removed from 800 litterbags in eight plots (100 litterbags per plot) was measured in Hluhluwe–iMfolozi Park (HiP) South Africa. These data were used to quantify variation in litter removal at two spatial scales: the local scale (within 450-m2 plots) and the landscape scale (among sites separated by 8–25 km). Subsequently, we attempted to understand the possible determinants of termites’ foraging patterns by testing various ecological correlates, such as plant biomass and bare ground at small scales and rainfall and fences that excluded large mammalian herbivores at larger scales. No strong predictors for heterogeneity in termite foraging intensity were found at the local scale. At the landscape scale termite consumption depended on an interaction between rainfall and the presence of large mammalian herbivores: litter removal by termites was greater in the presence of large herbivores at the drier sites but lower in the presence of large herbivores at the wetter sites. The effect of herbivores on termite foraging intensity may indicate a switch between termites and large herbivore facilitation and competition across a productivity gradient. In general, litter removal decreased with increasing mean annual rainfall, which is in contrast to current understanding of termite consumption across rainfall and productivity gradients. These results generate novel insights into termite ecology and interactions among consumers of vastly different body sizes across spatial scales.

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Colonization of Urban Habitats: Tawny Owl Abundance Is Conditioned by Urbanization Structure

Animals ◽

10.3390/ani11102954 ◽

2021 ◽

Vol 11 (10) ◽

pp. 2954

Author(s):

Nerea Pagaldai ◽

Juan Arizaga ◽

María V. Jiménez-Franco ◽

Iñigo Zuberogoitia

Keyword(s):

Large Scale ◽

Basque Country ◽

Species Abundance ◽

Population Level ◽

Landscape Scale ◽

Local Scale ◽

Urban Structure ◽

Northern Spain ◽

Natural Habitats ◽

Tawny Owl

Natural habitats are being altered and destroyed worldwide due to urbanization, leading to a decrease in species abundance and richness. Nevertheless, some species, including tawny owls, have successfully colonized this novel habitat. Consequences at the population level have not been described; thus, our main objective was to describe the effects that urban structure have on the tawny owl population at local and landscape levels. Data were obtained from 527 survey points over 7 months in a large-scale owl survey in the Basque Country (northern Spain) in 2018. At the local scale, the interaction between forest and urban cover affected tawny owl abundance, the optimum being in medium forested areas. The interaction between urban cover and clumpiness index (urban patch distribution) showed a generally negative effect. At the landscape scale, its abundance decreased in complex-shaped urban patches and when distance between them was greater. In conclusion, at the local scale, when a minimal forest structure is present in urbanized areas, the species can exploit it. At the landscape scale, it prefers smaller urban towns to cities. Thinking ahead, the current tendency toward “green capitals” should benefit tawny owl populations.

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Importance of Autoinfection to the Epidemiology of Polycyclic Foliar Disease

Phytopathology ◽

10.1094/phyto-99-10-1116 ◽

2009 ◽

Vol 99 (10) ◽

pp. 1116-1120 ◽

Cited By ~ 25

Author(s):

Christopher C. Mundt

Keyword(s):

Disease Progression ◽

Spatial Scales ◽

Landscape Scale ◽

Local Scale ◽

Microbial Interactions ◽

Disease Spread ◽

Potential Importance ◽

Plant Populations ◽

Foliar Disease ◽

Qualitative And Quantitative

Autoinfection (infection resulting from inoculum produced on the same host unit) can result in strongly clustered disease at the local scale. In contrast, much epidemiological theory incorporates the simplification of spatially random or uniform infection. Earlier studies suggested only low to moderate levels of autoinfection, especially when the host unit is small. However, several studies published within the last 5 years suggest that autoinfection rates may be substantially higher than previously indicated. I discuss the potential importance of accounting for high autoinfection rates in example epidemiological processes that occur at different spatial scales: microbial interactions on the phylloplane, temporal disease progression in plant populations, and spatiotemporal disease spread at the landscape scale. Accounting for high autoinfection rates can have important qualitative and quantitative consequences for epidemiological processes, and further studies of autoinfection will contribute significantly to our understanding of epidemics.

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Fire effects on pollination in a sexually deceptive orchid

International Journal of Wildland Fire ◽

10.1071/wf15172 ◽

2016 ◽

Vol 25 (8) ◽

pp. 888 ◽

Cited By ~ 7

Author(s):

Julian Brown ◽

Alan York ◽

Fiona Christie

Keyword(s):

Prescribed Fire ◽

Scale Effects ◽

Spatial Scales ◽

Fire Effects ◽

Landscape Scale ◽

Local Scale ◽

Agricultural Landscapes ◽

Pollinator Visitation ◽

Age Class ◽

Landscape Scales

Research into the effectiveness of prescribed fire in managing pollination has only recently begun. The effects of fire on pollination have not been explored in sexually deceptive systems. Further, the potential for multiple effects operating at different spatial scales has not been explored in any pollination system despite multiscale effects on pollination observed in agricultural landscapes. We observed the frequency of pollinator visitation to flowers of sexually deceptive Caladenia tentaculata and related it to the post-fire age class of the vegetation at local and landscape scales. We also related the number of the pollinator’s putative larval hosts (scarab beetles) captured at these sites to age class. At the local scale (i.e. the sample location), visitation was highest in recently burnt sites. At the landscape scale, positive associations were observed between (1) putative pollinator hosts and vegetation burnt 36–50 years ago, and (2) pollinator visitation and vegetation burnt ≥50 years ago. Local- and landscape-scale effects on visitation were synergistic, such that visitation was greatest when fire age was heterogeneous within pollinator foraging range.

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Effect of land use in seasonal abundance of Eared Dove (Zenaida auriculata) in Southwestern Brazil

Brazilian Journal of Biology ◽

10.1590/1519-6984.21115 ◽

2017 ◽

Vol 78 (1) ◽

pp. 18-24

Author(s):

G. G. Silva ◽

D. L. Guadagnin

Keyword(s):

Land Use ◽

Agricultural Land ◽

Large Population ◽

Agricultural Practices ◽

Common Species ◽

Landscape Scale ◽

Local Scale ◽

Seasonal Abundance ◽

Landscape Matrix ◽

Point Count

Abstract Changes at the landscape scale associated with expansion in agricultural land use and changes in agricultural practices are common causes of alteration in patterns of abundance and composition of avian communities. Eared Dove (Zenaida auriculata - Des Murs, 1847) is among the most common species in the Neotropics, considered both as game and pest in some countries. Here we characterized the regional and seasonal patterns of Eared Doves abundance in Southwestern Brazil and examined the relationship between landscape features and these abundance patterns. We counted Eared Doves using the point count system along routes in summer and winter and recorded land use at two scales. We used linear regressions to model the effect of landscape matrix and land use at local scale with Doves abundance in two seasons. At the landscape scale, in winter, the abundance was greater in routes crossing landscapes dominated by plantations. In summer, it was lower in routes with large tracts of forests and mixed farming. While in winter, at the local scale, the Doves abundance was greater in routes with higher frequency of maize plantations, in summer higher abundances were observed in routes with higher frequency of sugar cane and soybean plantations. Agricultural settings, which include both sustained production of food in the form of grains as well as and large stretches of habitat suitable for reproduction, favor large population of Eared Doves.

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Local and landscape drivers of aquatic-to-terrestrial subsidies in riparian ecosystems: a worldwide meta-analysis

10.1101/446815 ◽

2018 ◽

Author(s):

D. Lafage ◽

E. Bergman ◽

R. L. Eckstein ◽

M. Österling ◽

J.P. Sadler ◽

...

Keyword(s):

Land Use ◽

Meta Analysis ◽

Landscape Scale ◽

Local Scale ◽

Tree Cover ◽

Riparian Ecosystems ◽

Annual Variations ◽

Equal Importance ◽

Terrestrial Subsidies ◽

Anthropogenic Land Use

AbstractCross-boundary fluxes of organisms and matter, termed “subsidies”, are now recognized to be reciprocal and of roughly equal importance for both aquatic and terrestrial systems, even if terrestrial input to aquatic ecosystems has received most attention. The magnitude of aquatic to terrestrial subsidies is well documented, but the drivers behind these subsidies and their utilization by terrestrial consumers are characteristically local scale studies, limiting the inferences that can be drawn for broader geographic scales. We therefore built and analyzed a database of stable isotope data extracted from 21 studies worldwide, to identify both landscape and local scale variables that may affect the diet of terrestrial predators in riparian ecosystems. Our meta-analysis revealed a greater magnitude of aquatic-to-terrestrial subsidies (> 50%) than previously reported, albeit with large geographic and inter-annual variations. We demonstrated a large effect of landscape-scale factors on aquatic-to-terrestrial subsidies, particularly anthropogenic land use and tree cover. Local human population was the only relevant factor at the local scale. We also found that studies on landscape-scale and anthropogenic land use effects on aquatic-to-terrestrial subsidies are currently strongly under-represented in the ecological literature. Such studies are needed to improve our understanding of how land use and environmental change might influence future patterns of biodiversity and ecosystem function.

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Perspectives for the application of computer models to forest dynamics forecasting in bieszczadzki national park (Poland)

Ekológia (Bratislava) ◽

10.2478/eko-2014-0003 ◽

2014 ◽

Vol 33 (1) ◽

Author(s):

Ihor Kozak ◽

Kajetan Perzanowski ◽

Stanisław Kucharzyk ◽

Krystyna Przybylska ◽

Stanisław Zięba ◽

...

Keyword(s):

National Park ◽

Prognostic Model ◽

Single Cells ◽

Computer Models ◽

Landscape Scale ◽

Local Scale ◽

Tree Stand ◽

Forest Development ◽

Mathematical Relationships ◽

Self Learning

AbstractThis paper presents the perspectives for application of computer models in forecasting the dynamics of forest development on example of Moczarne area, in Bieszczadzki National Park, based on authors’ computer models. First, the possibilities for forecasting the dynamics of forest development in a local scale, i.e. within single rectangular or circular study plot, are presented. For this purpose, a computer prognostic model FORKOM E has been applied, using both general mathematical relationships functioning within a forest ecosystem and empirical ones, characteristic for tree stands at analysed plots. Additionally, a layer of 3D visualisation of a tree stand, which is an integral part of the mentioned model, is also presented. Presented also are the possibilities for forecasting the dynamics of forest development at landscape scale, applying the theory of cellular automata. For this purpose, a prognostic computer model CELLAUT was used in which the whole analysed tree stand is understood as a set of single cells, where stages of landscape development dominating within those cells are considered as also the influence of particular cells upon their neighbours. The paper also describes the perspectives for application of self-learning neural networks in the process of supplementation and verification of some parameters of a tree stand, calculated by the above-mentioned models.

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Managing Centrarchid Fisheries in Rivers and Streams

Managing Centrarchid Fisheries in Rivers and Streams ◽

10.47886/9781934874523.ch3 ◽

2019 ◽

Keyword(s):

Classification Tree ◽

Site Occupancy ◽

Landscape Scale ◽

Local Scale ◽

Error Rates ◽

Smallmouth Bass ◽

Site Specific ◽

Forest Classification ◽

Black Bass ◽

Scale Data

Abstract.—Black bass Micropterus spp. are among the most popular sportfish species in North America, however, managers currently have insufficient information about patterns and drivers of their distribution. Tradeoffs exist with the spatial scale at which to collect information associated with the distribution of species. Local-scale data are expensive to collect, but are likely directly associated with occupancy of a particular site. Landscape-scale data are increasingly available, are easily scaled and linked to site occupancy, but management often does not occur at this scale. We utilized site-specific habitat data collected as part of a statewide stream sampling program from 2002 to 2013 to generate presence–absence data for Smallmouth Bass M. dolomieu. We used site specific local-scale, landscape-scale, and a combination of local- and landscape-scale data to create random forest classification tree models of Smallmouth Bass presence and absence. All three models had similar total error rates ranging from 13.9% to 16.6%. Overall rates of success and error did not differ among the three models ( P = 0.95). The model using only landscape-scale data were used to predict the presence or absence of Smallmouth Bass for all Michigan stream segments and had an error rate of 17% based on an independent data validation. These data suggest that our approach has utility for predicting Smallmouth Bass occurrence in Michigan streams by identifying important habitat features associated with Smallmouth Bass occurrence. This approach could be extended to understand the distribution of other black bass species in locations where distributional data may be more limited.

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