scholarly journals Avian Studies in Montane Meadows: Songbird Abundance and Nesting Success

2002 ◽  
Vol 26 ◽  
pp. 126-131
Author(s):  
Ron Vannimwegen ◽  
Diane Debinski
Keyword(s):  
Earth Sciences ◽  
Climate Change ◽  
Species Diversity ◽  
Global Climate Change ◽  
Biological Diversity ◽  
Global Climate ◽  
Systematic Sampling ◽  
Remotely Sensed Data ◽  
Good Decision ◽  
Taxonomic Groups

The loss of biological diversity has become a global concern during the last decade (Wilson, 1988; Reid and Miller, 1989). The need to predict those species of concern and areas of high species richness is even more pressing as we enter an era of potential global climate change. Prerequisites to good decision-making with regard to the management of biological diversity are adequate floral and faunal inventories for the lands in question and a rigorous understanding of species-habitat relationships (e.g., Noss, 1983; Davis et al., 1990; Scott et al., 1990; Scott et al., 1993). The emergence of landscape ecology as a discipline has been instrumental in helping scientists understand spatial patterns of species distribution (Noss, 1983; Urban et al., 1987; Turner, 1989). Once these relationships are understood, it may be possible to predict species diversity based upon landscape level habitat analysis using geographic information systems (GIS) and remotely sensed data (Urban et al., 1987; Turner, 1989) at fine-scale resolutions (e.g., 20 - 50 meter sampling sites). Conversely, such analyses can help optimize sampling strategies or allow us to test hypotheses regarding the spatial correspondence of species diversity "hotspots" among taxonomic groups (e.g. Prendergast et al., 1993). The debate over global climate change has created renewed interest in documenting baseline variability in biodiversity. Goals of the Committee on Earth Sciences (1989) regarding the U.S. Global Change Research Program focus on the development of sound scientific strategies for monitoring and predicting environmental change. Key priorities, as noted by the committee, are as follows: "Systematic sampling and monitoring are essential to document critical natural versus human-induced change in the structure and function of globally relevant biological systems on various time scales." (Committee on Earth Sciences, 1989).

scholarly journals Shifts in phenology due to global climate change: the need for a yardstick

2005 ◽  
Vol 272 (1581) ◽  
pp. 2561-2569 ◽  
Author(s):  
Marcel E Visser ◽  
Christiaan Both
Keyword(s):  
Climate Change ◽  
Global Climate Change ◽  
Global Climate ◽  
Natural World ◽  
First Approximation ◽  
Taxonomic Groups ◽  
Almost All ◽  
The Impact ◽  
Species Shifts

Climate change has led to shifts in phenology in many species distributed widely across taxonomic groups. It is, however, unclear how we should interpret these shifts without some sort of a yardstick: a measure that will reflect how much a species should be shifting to match the change in its environment caused by climate change. Here, we assume that the shift in the phenology of a species' food abundance is, by a first approximation, an appropriate yardstick. We review the few examples that are available, ranging from birds to marine plankton. In almost all of these examples, the phenology of the focal species shifts either too little (five out of 11) or too much (three out of 11) compared to the yardstick. Thus, many species are becoming mistimed due to climate change. We urge researchers with long-term datasets on phenology to link their data with those that may serve as a yardstick, because documentation of the incidence of climate change-induced mistiming is crucial in assessing the impact of global climate change on the natural world.

scholarly journals A Preliminary Assessment of Forest Canopy Structure in Grand Teton National Park

1994 ◽  
Vol 18 ◽  
pp. 37-41
Author(s):  
Clayton Blodgett ◽  
Mark Jakubauskas
Keyword(s):  
Climate Change ◽  
Spatial Autocorrelation ◽  
Global Climate Change ◽  
Spatial Dependence ◽  
Forest Canopy ◽  
Global Climate ◽  
Canopy Structure ◽  
Remotely Sensed ◽  
Remotely Sensed Data ◽  
Geostatistical Techniques

The potential impact of environmental change on human welfare has renewed interest in understanding the patterns and processes associated with global climate change. Goals of the Committee on Earth Sciences (1989) regarding the U.S. Global Climate Change Program concentrated on the development of sound scientific strategies for monitoring and predicting environmental change. The scaling of ecological characteristics from local to regional and global scales were identified by the Committee as key priorities. The scaling of ecological information is not simply done by integrating or aggregating information from local scale investigations to regional and global scales (Caldwell et al., 1993). The complexity of the effects of scale variations rules out the use of simple generalizations (Foody and Curran, 1994). Information that is significant at local scales may be trivial when evaluated at regional or global scales. Biological interactions with the environment occur over many scales, suggesting a role for multiscale analysis in the description of these interactions (Sclmeider, 1994). Methods must be developed to better understand and evaluate ecological processes operating at multiple scales. Forest structure attributes have been measured using remotely sensed data. Leaf area index (LAI), for example, has been related to the infrared/red ratio (Running et al., 1986 Peterson et al., 1987), the normalized difference vegetation index (NDVI) (Leblon et al., 1993), and gap fractions (Nel and Wessman, 1993). These methods generate values for each pixel in a satellite scene based on the relationship between one or more spectral and/or ancillary data channels and the attribute of interest. The spatial autocorrelation or spatial dependence present in surface phenomena and satellite data are usually not ex-ploited during attribute assignment because of difficulty in quantifying the spatial patterns present (Woodcock et al., 1988). Geostatistics provides a statistically based technique to quantify spatial pattern. Geostatistical techniques, in particular cokriging, can serve as an efficient means of modeling forest canopy structure at a variety of spatial scales to serve as inputs to global change models. The key issue will be to determine the factors that influence remotely sensed spectral reflectance and relating them to the ecological model across scales (Ustin et al., 1993). The geostatistical techniques considered in this research include the following: the semivariograrn, which allows the user to compare values of a random variable at two points separated by a given lag distance (Milne, 1991); kriging which uses the information on spatial dependence present in the semivariogram to estimate values at unsampled locations based on scattered sample data (lsaaks and Srivastava, 1989); and cokriging, the multivariate extension of kriging, which is appropriate when two or more variables are spatially interdependent and the variable of interest is undersampled (McBratney and Webster, 1983; Leenaers et al., 1989). Geostatistical techniques have been successfully applied to remotely sensed data. Variograms have been used to determine components of coniferous canopy structure (Cohen et al., 1990), and to determine the spatial autocorrelation structure of Landsat Thematic Mapper (IM) imagery and intercepted photosynthetically active radiation (IPAR) (Lathrop and Pierce, 1991). Atkinson et al. (1992) used cokriging of ground-based radiometer data to estimate LAI, dry biomass and percent cover. Satellite imagery is an excellent candidate for inclusion as an explanatory variable in the cokriging process because it is an exhaustive sample of a given area.

scholarly journals Hydrothermal physiology and climate vulnerability in amphibians

2021 ◽  
Vol 288 (1945) ◽  
pp. 20202273
Author(s):  
Dan A. Greenberg ◽  
Wendy J. Palen
Keyword(s):  
Climate Change ◽  
Biological Diversity ◽  
Functional Performance ◽  
Global Climate ◽  
Future Climate Change ◽  
Climate Conditions ◽  
Species Activity ◽  
Climate Vulnerability ◽  
Species Specific ◽  
Taxonomic Groups

Concerns over the consequences of global climate change for biodiversity have spurred a renewed interest in organismal thermal physiology. However, temperature is only one of many environmental axes poised to change in the future. In particular, hydrologic regimes are also expected to shift concurrently with temperature in many regions, yet our understanding of how thermal and hydration physiology jointly affect performance and fitness is still limited for most taxonomic groups. Here, we investigated the relationship between functional performance, hydration state and temperature in three ecologically distinct amphibians, and compare how temperature and water loss can concurrently limit activity under current climate conditions. We found that performance was maintained across a broad range of hydration states in all three species, but then declines abruptly after a threshold of 20–30% mass loss. This rapid performance decline was accelerated when individuals were exposed to warmer temperatures. Combining our empirical hydrothermal performance curves with species-specific biophysical models, we estimated that dehydration can increase restrictions on species' activity by up to 60% compared to restriction by temperature alone. These results illustrate the importance of integrating species' hydration physiology into forecasts of climate vulnerability, as omitting this axis may significantly underestimate the effects of future climate change on Earth's biological diversity.

scholarly journals Bats Species Diversity of Northern Tajikistan: 45 Years Later

2021 ◽  
Vol 35 ◽  
pp. 00013
Author(s):  
Tolibjon Khabilov ◽  
Dilbar Tadjibaeva
Keyword(s):  
Climate Change ◽  
Species Diversity ◽  
Global Climate Change ◽  
Global Climate ◽  
Field Studies ◽  
Abandoned Mines ◽  
Northern Slope ◽  
Mountain Ranges ◽  
Term Field

The paper shows the results of long-term field studies of the species composition and number of bats in 8 abandoned mines in the Mogol-Tau mountains and the foothills of the northern slope of the Turkestan Mountain ranges in the territory of Northern Tajikistan. It reveals that the species diversity and number of bats have decreased both in “winter” stationary mine in the Mogol-Tau mountains and in “summer” stationary mine in the foothills of the Turkestan Mountain ranges. At the same time, the number of Myotis blythii Tomes 1857 has remarkably increased in summer. The paper suggests that these changes are not directly related to human activities, but have deeper causes and, possibly, are associated with global climate change.

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