Bird research in the ACWERN lab at the Faculty of Forestry and Environmental Management, University of New Brunswick

2008 ◽  
Vol 84 (4) ◽  
pp. 548-552 ◽  
Author(s):  
Antony W Diamond

Research on forest bird ecology in the ACWERN (Atlantic Cooperative Wildlife Ecology Research Network) lab at the University of New Brunswick, Fredericton, since 1995 has focused on assessing the relative contributions of habitat quality at large (“landscape”) and small (“local” or “stand”) spatial scales. To do so we had to develop methods for assessing key demographic components of fitness (productivity and survival) at large spatial scales. The large extent of forest cover in the Maritimes contrasts with regions where such work has traditionally been carried out, in which forest is clearly fragmented by agriculture or residential development. Our main findings are that spatial effects in highly forested landscapes can often be detected only by using species-specific habitat models, rather than broader categories such as “mature” or “softwood”, that Blackburnian Warblers (Dendroica fusca) are effective indicators of mixedwood forest but define it differently than forest managers do, and that cavity nesters (e.g., woodpeckers) may require different habitat components for nesting and feeding and so cannot be managed for solely on the basis of providing snags for nesting. Our focus has shifted recently to intensive studies on a species at risk, Bicknell's Thrush (Catharus bicknelli), which in New Brunswick breeds in man-made regenerating softwood forest stands, and assessing its response both to precommercial thinning of the breeding habitat and to effects carrying over from the winter habitat in the Caribbean. Key words: landscape effects, thresholds, survival, productivity, fitness, carry-over, habitat, fragmentation

2010 ◽  
Vol 86 (3) ◽  
pp. 354-364 ◽  
Author(s):  
Henrik Hartmann ◽  
Gaëtan Daoust ◽  
Brigitte Bigué

Terrestrial biodiversity is closely linked to forest ecosystems but anthropogenic reductions in forest cover and changes in forest structure and composition jeopardize their biodiversity. Several forest species are threatened because of reduced habitat quality and fragmentation or even habitat loss as a result of forest management activities. In response to this threat, integrated forest management (IFM) was developed in the early 1990s and has been applied over large spatial scales ever since. While IFM seeks to satisfy both human resource demands and ecosystem integrity, the whole forest matrix is affected and this may also have negative impacts on biodiversity. The concept of forest zoning (e.g., Triad) avoids these issues by physically separating land uses from each other. The zoning approach has been developed in the same period as IFM, but there are still very few examples of large-scale applications. This may be because its distinctiveness from IFM may not always seem clear and because forest zoning is not easily implemented. Here we explain these differences and show that IFM and the zoning approach are indeed different management paradigms. We advocate the use of high-yield plantations within the zoning paradigm as a means for biodiversity conservation and review the literature (with an emphasis on the northern hemisphere and on plantation forestry within a land-zoning approach) on impacts of forest management activities on biodiversity. Furthermore, we give advice on issues that require consideration when implementing forest zoning at both the stand and the landscape levels. We recommend several small changes in design and management of forest plantations as a means to significantly increase their biodiversity value. We conclude that while forest zoning seems an adequate strategy for the Canadian forestry sector, a shift in paradigm must carry over to policy-makers and legislation if this approach is to succeed. Key words: biodiversity, landbase zoning, forest management, intensive silviculture, plantation forests


2021 ◽  
Vol 21 (3) ◽  
Author(s):  
Oscar V. Bautista-Cespedes ◽  
Louise Willemen ◽  
Augusto Castro-Nunez ◽  
Thomas A. Groen

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.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Gaëtane Le Provost ◽  
Jan Thiele ◽  
Catrin Westphal ◽  
Caterina Penone ◽  
Eric Allan ◽  
...  

AbstractLand-use intensification is a major driver of biodiversity loss. However, understanding how different components of land use drive biodiversity loss requires the investigation of multiple trophic levels across spatial scales. Using data from 150 agricultural grasslands in central Europe, we assess the influence of multiple components of local- and landscape-level land use on more than 4,000 above- and belowground taxa, spanning 20 trophic groups. Plot-level land-use intensity is strongly and negatively associated with aboveground trophic groups, but positively or not associated with belowground trophic groups. Meanwhile, both above- and belowground trophic groups respond to landscape-level land use, but to different drivers: aboveground diversity of grasslands is promoted by diverse surrounding land-cover, while belowground diversity is positively related to a high permanent forest cover in the surrounding landscape. These results highlight a role of landscape-level land use in shaping belowground communities, and suggest that revised agroecosystem management strategies are needed to conserve whole-ecosystem biodiversity.


2011 ◽  
Vol 87 (05) ◽  
pp. 612-624 ◽  
Author(s):  
Eric Alvarez ◽  
Louis Bélanger ◽  
Louis Archambault ◽  
Frédéric Raulier

Pre-industrial forest cover portrait is a recognized method for establishing the bases of sustainable forest management. However, it is a spatially and temporally dependant concept that should be used with caution in presence of big fires. The objective of the study was to portray the pre-industrial landscape in a mixedwood temperate forest in central Quebec at different spatial scales. The study was based on archival records from a forest company. The pre-industrial forest cover landscape of our study area was mainly composed of mature or old-growth (>100 years) stands and dominated by mixedwood forest stands with intolerant hardwoods. The main tree species were white birch, black spruce and jack pine, three species associated to forest succession after fire in the boreal forest. Considering the great variability caused by the fires and partial knowledge of this variability, for each spatial scale considered, we propose some management targets based on the main pre-industrial characteristics of this forest. To respect the pre-industrial variability, our study suggested that silviculture should be adapted at different landscape scales. Cover types and age class targets should be based on main preindustrial characteristics at each landscape scale analyzed.


Author(s):  
Brady S. Hardiman ◽  
Elizabeth A. LaRue ◽  
Jeff W. Atkins ◽  
Robert T. Fahey ◽  
Franklin W. Wagner ◽  
...  

Forest canopy structure (CS) controls many ecosystem functions and is highly variable across landscapes, but the magnitude and scale of this variation is not well understood. We used a portable canopy lidar system to characterize variation in five categories of CS along N = 3 transects (140–800 m long) at each of six forested landscapes within the eastern USA. The cumulative coefficient of variation was calculated for subsegments of each transect to determine the point of stability for individual CS metrics. We then quantified the scale at which CS is autocorrelated using Moran’s I in an Incremental Autocorrelation analysis. All CS metrics reached stable values within 300 m but varied substantially within and among forested landscapes. A stable point of 300 m for CS metrics corresponds with the spatial extent that many ecosystem functions are measured and modeled. Additionally, CS metrics were spatially autocorrelated at 40 to 88 m, suggesting that patch scale disturbance or environmental factors drive these patterns. Our study shows CS is heterogeneous across temperate forest landscapes at the scale of 10’s of meters, requiring a resolution of this size for upscaling CS with remote sensing to large spatial scales.


Rangifer ◽  
1996 ◽  
Vol 16 (4) ◽  
pp. 119 ◽  
Author(s):  
Deborah B. Cichowski

Initial long term planning for logging on the Tweedsmuir-Entiako caribou winter range began in the early 1980s. Because little information was available on which to base winter range management, the British Columbia Fish and Wildlife Branch began studies on radio-collared caribou in 1983, and an intensive study on caribou winter habitat requirements was conducted from 1985 to 1988. Terrestrial lichens were identified as the primary winter food source for the caribou, and in 1987, caribou winter range ecosystem maps, which emphasized abundance of terrestrial lichens, were produced. The ecosystem maps and information from the caribou study, including potential direct and indirect effects of timber harvesting on the caribou population, were used to develop a management strategy for the winter range. The management strategy comprised two levels of management: a landscape level (Caribou Management Zones); and a site-specific level (caribou habitat/timber values). Timber information associated with BC Ministry of Forests forest cover maps was integrated using a Geographic Information System. Six winter range management options were proposed ranging from harvesting low value caribou habitats only throughout the winter range to total protection of the entire winter range. Impacts of those options on both the caribou population and on the timber supply were evaluated. The options were reviewed through a public planning process, the Entiako Local Resource Use Plan, and recommendations from that process were forwarded to the British Columbia Protected Areas Strategy.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Ishtiaq Mawla ◽  
Andrew Schrepf ◽  
Eric Ichesco ◽  
Steven E. Harte ◽  
David J. Klumpp ◽  
...  

AbstractNeural circuitry regulating urine storage in humans has been largely inferred from fMRI during urodynamic studies driven by catheter infusion of fluid into the bladder. However, urodynamic testing may be confounded by artificially filling the bladder repeatedly at a high rate and examining associated time-locked changes in fMRI signals. Here we describe and test a more ecologically-valid paradigm to study the brain response to bladder filling by (1) filling the bladder naturally with oral water ingestion, (2) examining resting state fMRI (rs-fMRI) which is more natural since it is not linked with a specific stimulus, and (3) relating rs-fMRI measures to self-report (urinary urge) and physiologic measures (voided volume). To establish appropriate controls and analyses for future clinical studies, here we analyze data collected from healthy individuals (N = 62) as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network. Participants orally ingested approximately 350 mL of water, and had a 10 min “fuller bladder” rs-fMRI scan approximately 1 h later. A second 10 min “empty bladder” rs-fMRI scan was conducted immediately following micturition. We examined multiple spatial scales of brain function, including local activity, circuits, and networks. We found changes in brain function distributed across micturition loci (e.g., subregions of the salience, sensorimotor, and default networks) that were significantly related to the stimulus (volume) and response (urinary urge). Based on our results, this paradigm can be applied in the future to study the neurobiological underpinnings of urologic conditions.


Geosciences ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 322 ◽  
Author(s):  
John B. Lindsay ◽  
Daniel R. Newman ◽  
Anthony Francioni

Surface roughness is a terrain parameter that has been widely applied to the study of geomorphological processes. One of the main challenges in studying roughness is its highly scale-dependent nature. Determining appropriate mapping scales in topographically heterogenous landscapes can be difficult. A method is presented for estimating multiscale surface roughness based on the standard deviation of surface normals. This method utilizes scale partitioning and integral image processing to isolate scales of surface complexity. The computational efficiency of the method enables high scale sampling density and identification of maximum roughness for each grid cell in a digital elevation model (DEM). The approach was applied to a 0.5 m resolution LiDAR DEM of a 210 km2 area near Brantford, Canada. The case study demonstrated substantial heterogeneity in roughness properties. At shorter scales, tillage patterns and other micro-topography associated with ground beneath forest cover dominated roughness scale signatures. Extensive agricultural land-use resulted in 35.6% of the site exhibiting maximum roughness at micro-topographic scales. At larger spatial scales, rolling morainal topography and fluvial landforms, including incised channels and meander cut banks, were associated with maximum surface roughness. This method allowed for roughness mapping at spatial scales that are locally adapted to the topographic context of each individual grid cell within a DEM. Furthermore, the analysis revealed significant differences in roughness characteristics among soil texture categories, demonstrating the practical utility of locally adaptive, scale-optimized roughness.


2007 ◽  
Vol 58 (2) ◽  
pp. 204 ◽  
Author(s):  
Alan R. Duckworth ◽  
Carsten W. Wolff

Distribution and size frequency patterns of sessile organisms such as sponges may vary among and within neighbouring reefs. In the present study, we examined small-scale variation of dictyoceratid sponges (class Demospongiae), commonly found on coral reefs, by surveying six neighbouring islands in central Torres Strait. Each island had four study sites, at least 1 km apart, with each site consisting of three shallow (4 to 6 m) and three deep (10 to 15 m) 20 m2 transects. For each transect, we recorded the number of each species and measured the size of the more common dictyoceratid sponges. Seven species of dictyoceratid were recorded in central Torres Strait, with only three species, Coscinoderma sp., Dysidea herbacea and Hyrtios erecta, common to all six islands. Abundance patterns generally varied greatly among islands or sites within islands, perhaps resulting from a combination of physical, biological and stochastic factors. More dictyoceratids were found in deeper water; however, abundance across depth for some species varied among islands or sites. Size-frequency distribution patterns also varied greatly among islands and dictyoceratid species, indicating that factors that may promote growth for one species may not necessarily promote growth for a related species. This study shows that patterns of abundance and size of dictyoceratids can vary greatly over small spatial scales, and that patterns are species-specific.


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