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991.
In reply to the critique of Baird and Kerr, we emphasize that our model is a generalized vulnerability model, built from easily
acquired data from anywhere in the world, to identify areas with probable susceptibility to large tsunamis—and discuss their
other criticisms in detail. We also show that a rejection of the role of trees in helping protect vulnerable areas is not
justified in light of existing evidence. 相似文献
992.
Landscape context influences many aspects of songbird ecology during the breeding season. The importance of landscape context
at stopover sites for migrating songbirds, however, has received less attention. In particular, landscape context may affect
the availability and quality of food for refueling during stopovers, which is critical for successful migration. We evaluated
the influence of woody habitat cover in the surroundings of stopover sites at several spatial extents on the hourly changes
of body mass in two species of European-African forest-dwelling songbird migrants (Willow Warbler, Phylloscopus trochilus, and the Eurasian Redstart, Phoenicurus phoenicurus). Data were sampled by standardized methods from a network of ringing stations throughout Europe during the falls of 1994–1996.
In both species, hourly body mass gain calculated for first captures increased with woody habitat cover. We found a similar
logarithmic relationship for both species, although for Willow Warblers mass gain was more strongly related to the habitat
cover within 5 km, in contrast to 3 km for Redstarts. For Willow Warblers, where sufficient data are available for each year,
the relationship is consistent over the years. The shape of the relationship suggests existence of a threshold of landscape
suitability for refueling at stopover sites: in sites with less than 10% of woody habitat cover, birds tend to lose body mass
or to gain mass at a lower rate.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
993.
Kirtland’s warblers (Dendroica kirtlandii) persist in a naturally patchy environment of young, regenerating jack pine forests (i.e., 5–23 years old) created after
wildfires and human logging activities. We examined how changing landscape structure from 26 years of forest management and
wildfire disturbances influenced population size and spatial dispersion of male Kirtland’s warblers within their restricted
breeding range in northern Lower Michigan, USA. The male Kirtland’s warbler population was six times larger in 2004 (1,322)
compared to 1979 (205); the change was nonlinear with 1987 and 1994 identified as significant points of change. In 1987, the
population trend began increasing after a slowly declining trend prior to 1987, and the rate of increase appeared to slow
after 1994. Total amount of suitable habitat and the relative area of wildfire-regenerated habitat were the most important
factors explaining population trend. Suitable habitat increased 149% primarily due to increasing plantations from forest management.
The relative amount and location of wildfire-regenerated habitat modified the distribution of males among various habitat
types, and the spatial variation in their abundance across the primary breeding range. These findings indicate that the Kirtland’s
warbler male population shifted its use of habitat types temporally and spatially as the population increased and as the relative
availability of habitats changed through time. We demonstrate that researchers and managers need to consider not only habitat
quality, but the temporal and the spatial context of habitat availability and population levels when making habitat restoration
decisions. 相似文献
994.
995.
996.
Background
High throughput DNA isolation from plants is a major bottleneck for most studies requiring large sample sizes. A variety of protocols have been developed for DNA isolation from plants. However, many species, including conifers, have high contents of secondary metabolites that interfere with the extraction process or the subsequent analysis steps. Here, we describe a procedure for high-throughput DNA isolation from conifers. 相似文献997.
Jeremy D Edwards Jaroslav Janda Megan T Sweeney Ambika B Gaikwad Bin Liu Hei Leung David W Galbraith 《Plant methods》2008,4(1):13
Background
We report the development of a microarray platform for rapid and cost-effective genetic mapping, and its evaluation using rice as a model. In contrast to methods employing whole-genome tiling microarrays for genotyping, our method is based on low-cost spotted microarray production, focusing only on known polymorphic features. 相似文献998.
Andrew G. Merschel Emily K. Heyerdahl Thomas A. Spies Rachel A. Loehman 《Landscape Ecology》2018,33(7):1195-1209
Context
In the interior Northwest, debate over restoring mixed-conifer forests after a century of fire exclusion is hampered by poor understanding of the pattern and causes of spatial variation in historical fire regimes.Objectives
To identify the roles of topography, landscape structure, and forest type in driving spatial variation in historical fire regimes in mixed-conifer forests of central Oregon.Methods
We used tree rings to reconstruct multicentury fire and forest histories at 105 plots over 10,393 ha. We classified fire regimes into four types and assessed whether they varied with topography, the location of fuel-limited pumice basins that inhibit fire spread, and an updated classification of forest type.Results
We identified four fire-regime types and six forest types. Although surface fires were frequent and often extensive, severe fires were rare in all four types. Fire regimes varied with some aspects of topography (elevation), but not others (slope or aspect) and with the distribution of pumice basins. Fire regimes did not strictly co-vary with mixed-conifer forest types.Conclusions
Our work reveals the persistent influence of landscape structure on spatial variation in historical fire regimes and can help inform discussions about appropriate restoration of fire-excluded forests in the interior Northwest. Where the goal is to restore historical fire regimes at landscape scales, managers may want to consider the influence of topoedaphic and vegetation patch types that could affect fire spread and ignition frequency.999.
Context
The roosting habits of many temperate zone bats are well documented at microhabitat scales, but fewer studies have included multi-scale assessments of landscape patterns in bat roost site selection.Objectives
To identify and assess at the landscape-scale the location of spring and early season maternity roosts of female northern long-eared bats (Myotis septentrionalis) from 2015 to 2016 at Mammoth Cave National Park (MACA), Kentucky, USA.Methods
We used mist-nets and radiotelemetry to catch and track bats to roost trees across the landscape of MACA. Data on roosting sites were evaluated using spatial point pattern analysis to examine distributional trends of roosts. A variety of spatial covariates were used to model the effect of landscape pattern, including: forest type, elevation, and proximity to hibernacula, water, and road corridors.Results
Data indicate that roost locations of female northern long-eared bats in MACA were typically situated within 2000 m of known winter hibernacula, occurring more often at higher elevations in mesic upland deciduous forests, and in close proximity to water sources and roads. We present hypotheses to account for the patterns observed in relation to landscape features and habitat resources in the Park.Conclusions
Our data indicate that a more comprehensive understanding of habitat requirements which includes empirically-based, landscape-scale patterns, and not solely considerations at stand or local levels, could lead to better informed management policies targeting conservation of maternity habitat of forest-dwelling bats, including the northern long-eared bat, a species in decline throughout much of its distribution in North America.1000.
Balázs Deák Orsolya Valkó Péter Török András Kelemen Ádám Bede András István Csathó Béla Tóthmérész 《Landscape Ecology》2018,33(7):1117-1132