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Pacific-slope Flycatcher station lifetime productivity (STAPI) (log transformed) ranged between -0.034 and +0.606 with a mean value of +0.286 and a median value of +0.247. ________________________________________ Model 1 (3 parameters) Pacific-slope Flycatcher station lifetime productivity (STAPI) (log transformed) was a function of: a) INTERCEPT (0.3022), b) NLCD06AF90P (+0.01874) - percent all forest cover, 90m-resolution(3x aggregation of 30m-resolution), ranged between -1.901 and +6.011 (95% CL) with a mean value of +2.055 and a median value of +2.494, c) NLCD06IM33P (-0.02730) - percent impervious cover, 990m-resolution (33x aggregation of 30m-resolution), ranged between -1.057 and +5.084 (95% CL) with...
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MAPS Station information: • Geographic locations and operating history of MAPS stations operated during the years 1989-2003. • A Microsoft Word document stations.doc describes field names
To investigate whether Northern Goshawk textit(Accipiter gentilis) reproduction is food-limited, we evaluated the reproductive output from 401 goshawk breeding opportunities on the Kaibab Plateau, Arizona during 1999-2002. Concurrently, we estimated densities of 10 goshawk prey species (seven birds, three mammals) using distance sampling. We then assessed the relationship between goshawk productivity (number of fledglings produced) and prey density within and among years by relating the contribution of individual prey species and total prey density to goshawk productivity. We also estimated the proportion of total diet and biomass for each species that contributed ?3% of all prey items. Total prey density was highly...
We investigated experimental warming and simulated grazing (clipping) effects on rangeland quality, as indicated by vegetation production and nutritive quality, in winter-grazed meadows and summer-grazed shrublands on the Tibetan Plateau, a rangeland system experiencing climatic and pastoral land use changes. Warming decreased total aboveground net primary productivity (ANPP) by 40 g.m?�.yr?� at the meadow habitats and decreased palatable ANPP (total ANPP minus non-palatable forb ANPP) by 10 g.m?�.yr?� at both habitats. The decreased production of the medicinal forb Gentiana straminea and the increased production of the non-palatable forb Stellera chamaejasme with warming also reduced rangeland quality. At the shrubland...
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Introduction : Swainson’s Thrush is a medium sized (15-18cm) thrush which prefers to breed in dense shrub growth associated with spruce-fir forests. The "russet-backed" race prefers mixed forests and deciduous riparian woodlands of the coastal region from British Columbia, to northern California. These Pacific populations winter in mature tropical and secondary forests of Central America, whereas the "olive-backed" race that breeds in the Boreal and Rockies winters in S. America. Models of Monitoring Avian Productivity and Survival (MAPS) demographic data and high-resolution land cover data showed that Swainson’s Thrush prefers large intact forest patches with low perimeter to area ratios. On a regional...
Concern over global environmental change and associated uncertainty has given rise to greater emphasis on fostering resilience through forest management. We examined the impact of standard silvicultural systems (including clearcutting, shelterwood, and selection) compared with unharvested controls on tree functional identity and functional diversity in three forest types distributed across the northeastern United States. Sites included the Argonne, Bartlett, and Penobscot Experimental Forests located in Wisconsin, New Hampshire, and Maine, respectively. We quantified functional trait means for leaf mass per area, specific gravity, maximum height, height achieved at 20 years, seed mass, drought tolerance, shade tolerance,...
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Data presented are results of surveys in 2021 for San Diego Cactus Wren (Campylorhynchus brunneicapillus) in southern San Diego County. Surveys were conducted at 378 plots. Plots were surveyed twice in 2021 and the number, age (adult or juvenile), banding status (color banded or not), and breeding status (paired, unpaired, or unknown) of all wrens recorded. Habitat covariate data were collected including amount of dead and stressed cactus in the plot, percent cover of bare ground, and the dominant and percent cover of invasive species.
Ecological processes of low-productivity ecosystems have long been considered to be driven by abiotic controls with biotic interactions playing an insignificant role. However, existing studies present conflicting evidence concerning the roles of these factors, in part due to the short temporal extent of most data sets and inability to test indirect effects of environmental variables modulated by biotic interactions. Using structural equation modeling to analyze 65 years of perennial vegetation change in the Sonoran Desert, we found that precipitation had a stronger positive effect on recruitment beneath existing canopies than in open microsites due to reduced evaporation rates. Variation in perennial canopy cover...
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The Dynamic Habitat Index (DHI) comprises of three indicators of the underlying vegetation dynamics derived from an annual sequence of MODIS monthly fPAR: (i) the cumulative annual greenness, (ii) the minimum level of perennial cover, and (iii) the degree of vegetation seasonality. The fPAR components were first computed for the years 2000-2005 and were then averaged to produce a long-term index of each component. The dataset is currently being used in conjunction with other datasets to help characterize ecosystem properties and biodiversity within the Canadian Boreal region (Brandt, 2009). Cited references: Brandt, J. 2009. The extent of the North American boreal zone. Environmental Reviews 17: 101-161. doi:10.1139/A39-004
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Distribution of Acadian Flycatcher productivity at MAPS stations during the period 1992-2008 throughout Midwestern states (plus 250km buffer).
Obtaining reliable estimates of absolute and relative reproductive rates is challenging for avian species whose nests are difficult to observe, such as the burrowing owl (Athene cunicularia). We compared methods for estimating reproductive rates of burrowing owls, defined as the number of 21- to 28-day-old young per Successful nest. We compared observations using (1) the mean and (2) the maximum number of young observed during 5 30-min observation periods, and (3) the maximum number of voting videotaped during 2-hr video surveillance. We evaluated the reliability of these methods with the known number of young present in nest boxes. All 3 methods performed poorly as estimators of absolute reproductive rates (absolute...
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Models of Monitoring Avian Productivity and Survival (MAPS) demographic data and high-resolution land cover data The top selected model of productivity indices suggested that productivity indices increased with distance from streams, where local coniferous forest cover (2km context) increased from 10 and 25% (mean `17%), within total forest cover of ~20% in a 2km context (N = 84, R2 = 0.26, P<0.0001). MacGillivray's Warbler station lifetime productivity (STAPI) (log transformed) ranged between +0.090 and +0.564 with a mean value of +0.327 and a median value of +0.325. ________________________________________ Model 1 (3 parameters) MacGillivray's Warbler station lifetime productivity (STAPI) (log transformed)...
Energy development is an integral part of enhanced economic development. The fact that expanded provision and use of energy services is strongly associated with economic development leaves open how important energy is as a causal factor in economic development, however; and energy development competes with other opportunities for scarce capital and opportunities for policy and institutional reform. In this paper we first give a brief conceptual discussion that seeks to identify the channels through which increased availability of energy services might be a key to stimulating economic development along different stages of the development process. We then examine some empirical work to see what evidence it might provide...
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This dataset represents the average C3 grass fraction (a biogeographic index based on the ratio of C3 to C4 grass) for each HUC5 watershed, simulated by the model MC1 for the 30-year period 1971-2000. Simulated mean C3 grass fraction was determined for each HUC5 watershed. Watersheds represent 5th level (HUC5, 10-digit) hydrologic unit boundaries and were acquired from the Natural Resources Conservation Service. Background: The dynamic global vegetation model MC1 (see Bachelet et al. 2001) was used to simulate vegetation dynamics, associated carbon and nitrogen cycle, water budget, and wild fire impacts for OR, WA, AZ and NM, for a project funded by the USDA Forest Service (PNW 09-JV-11261900-003). The MC1 model...
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Annual growth potential is an environmental data layer that is a proxy for annual plant biomass, which reflects potential forage for tortoises. This data layer was derived by calculating the difference in greenness (a measure of plant growth) between two highly contrasting years of annual plant production (Wallace and Thomas, 2008). The difference between MODIS-EVI images for 2002 (a very dry year) and 2005 (a very wet year) had high correlation with field measurements of annual plant cover collected on 36 plots in the Mojave National Preserve in 2005 (R2 = 0.63, p=0.01). The resulting values represent the potential for site specific food availability for desert tortoise.
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Distribution of Kentucky Warbler productivity at MAPS stations during the period 1992-2008 throughout Midwestern states (plus 250km buffer).
Climate change is causing measurable changes in rainfall patterns, and will likely cause increases in extreme rainfall events, with uncertain implications for key processes in ecosystem function and carbon cycling. We examined how variation in rainfall total quantity (Q), the interval between rainfall events (I), and individual event size (SE) affected soil water content (SWC) and three aspects of ecosystem function: leaf photosynthetic carbon gain (inline image), aboveground net primary productivity (ANPP), and soil respiration (inline image). We utilized rainout shelter-covered mesocosms (2.6 m3) containing assemblages of tallgrass prairie grasses and forbs. These were hand watered with 16 I�Q treatment combinations,...
Energy development is an integral part of enhanced economic development. The fact that expanded provision and use of energy services is strongly associated with economic development leaves open how important energy is as a causal factor in economic development, however; and energy development competes with other opportunities for scarce capital and opportunities for policy and institutional reform. In this paper we first give a brief conceptual discussion that seeks to identify the channels through which increased availability of energy services might be a key to stimulating economic development along different stages of the development process. We then examine some empirical work to see what evidence it might provide...
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This project links climate, hydrological, and ecological changes over the next 30 years in a Great Basin watershed. In recent years, climate variability on annual and decadal time scales has been recognized as greater than commonly perceived with increasing impacts on ecosystems and available water resources. Changes in vegetation distribution, composition and productivity resulting from climate change affect plant water use, which in turn can alter stream flow, groundwater and eventually available water resources. To better understand these links, project researchers implemented two computer-based numeric models in the Cleve Creek watershed in the Schell Creek Range, east of Ely, Nevada. The application of the...
Categories: Project; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: 2013, CASC, Cleve Creek, Climate, Completed, All tags...
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This dataset represents the average C3 grass fraction (a biogeographic index based on the ratio of C3 to C4 grass) for each HUC5 watershed, simulated by the model MC1 for the 30-year period 1971-2000. Simulated mean C3 grass fraction was determined for each HUC5 watershed. Watersheds represent 5th level (HUC5, 10-digit) hydrologic unit boundaries and were acquired from the Natural Resources Conservation Service. Background: The dynamic global vegetation model MC1 (see Bachelet et al. 2001) was used to simulate vegetation dynamics, associated carbon and nitrogen cycle, water budget, and wild fire impacts for OR, WA, AZ and NM, for a project funded by the USDA Forest Service (PNW 09-JV-11261900-003). The MC1...