Skip to main content
Advanced Search

Filters: Tags: Productivity (X)

30 results (17ms)   

Filters
Date Range
Extensions
Types
Contacts
Categories
Tag Types
Tag Schemes
View Results as: JSON ATOM CSV
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...
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,...
thumbnail
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...
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...
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...
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...
thumbnail
Data presented are results of surveys (2015) and monitoring (2015 and 2016) for San Diego Cactus Wren (Campylorhynchus brunneicapillus) in southern San Diego County. Surveys were conducted at 35 plots. Plots were surveyed twice in 2015 and the number, age (adult or juvenile), banding status (color banded or not), breeding status (paired, unpaired, or unknown), and nesting status (active nest detected or not) 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. During weekly monitoring visits, nests were located and checked to determine the number of eggs laid, the...
thumbnail
Data presented are results of surveys and monitoring in 2018 for San Diego Cactus Wren (Campylorhynchus brunneicapillus) in southern San Diego County. Surveys were conducted at 362 plots. Plots were surveyed twice in 2018 and the number, age (adult or juvenile), banding status (color banded or not), breeding status (paired, unpaired, or unknown), and nesting status (active nest detected or not) 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. During weekly monitoring visits, nests were located and checked to determine the number of eggs laid, the number of eggs...
thumbnail
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...
thumbnail
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
thumbnail
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...
We used microsensors to characterize physicochemical microenvironments and photosynthesis occurring immediately after water saturation in two desert soil crusts from southeastern Utah, which were formed by the cyanobacteria Microcoleus vaginatus Gomont, Nostoc spp., and Scytonema sp. The light fields within the crusts presented steep vertical gradients in magnitude and spectral composition. Near-surface light-trapping zones were formed due to the scattering nature of the sand particles, but strong light attenuation resulted in euphotic zones only ca. 1 mm deep, which were progressively enriched in longer wavelengths with depth. Rates of gross photosynthesis (3.4?9.4 mmol O2�m?2�h?1) and dark respiration (0.81?3.1...
thumbnail
We calculated estimates describing interannual variation in seed production for series of long-term seed or fruit production in 219 plant species. For each plant species, we compiled estimates of foliar nutrient concentrations as well as productivity and weather at the site of observation. Data was compiled in order to test whether interannual variation in seed production was greater in species with lower foliar nutrient concentrations or greater nutrient imbalances.
thumbnail
Macroclimatic drivers, such as temperature and rainfall regimes, greatly influence ecosystem structure and function in tidal saline wetlands. Understanding the ecological influence of macroclimatic drivers is important because it provides a foundation for anticipating the effects of climate change. Tidal saline wetlands include mangrove forests, salt marshes, and salt flats, which occupy similar geomorphic settings but different climatic regimes. However, most global- or regional-scale analyses have treated these wetlands as independent systems. Here we used climate and literature-derived ecological data from all three systems, collected across targeted regional-scale macroclimatic gradients, to test hypotheses...
thumbnail
Field crews from Northern Prairie Wildlife Research Center from 1991-1993 in Stutsman County, North Dakota and Pope and Stevens Counties, Minnesota, gathered nest success and fledgling data from nests found within Conservation Reserve Program fields and Waterfowl Production Areas. This dataset includes nesting observations of bird species found within these two field types. The dataset includes genus and species, vegetation height, distance to edge and perch, host nesting and fledgling variables, and parasitic nesting and fledgling variables.
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...


map background search result map search result map Understanding and Projecting Changes in Climate, Hydrology, and Ecology in the Great Basin for the Next 30 Years Simulated historical C3 grass fraction (1971-2000) for OR and WA, USA The Monitoring Avian Productivity and Survivorship (MAPS) Program Monitoring Network Stations Database Linear and nonlinear effects of temperature and precipitation on ecosystem properties in tidal saline wetlands Data on interannual variability of seed production, nutrient, and weather for 219 plant species Surveys and Monitoring of Coastal Cactus Wren in Southern San Diego County, 2015-2016 Surveys and Monitoring of Coastal Cactus Wren in Southern San Diego County, 2018 Surveys and Monitoring of Coastal Cactus Wren in Southern San Diego County, 2021 Density and Fledging Success Data from Conservation Reserve Program Fields in North Dakota and Minnesota, 1991-1993 Understanding and Projecting Changes in Climate, Hydrology, and Ecology in the Great Basin for the Next 30 Years Surveys and Monitoring of Coastal Cactus Wren in Southern San Diego County, 2015-2016 Surveys and Monitoring of Coastal Cactus Wren in Southern San Diego County, 2018 Surveys and Monitoring of Coastal Cactus Wren in Southern San Diego County, 2021 Density and Fledging Success Data from Conservation Reserve Program Fields in North Dakota and Minnesota, 1991-1993 Simulated historical C3 grass fraction (1971-2000) for OR and WA, USA The Monitoring Avian Productivity and Survivorship (MAPS) Program Monitoring Network Stations Database Linear and nonlinear effects of temperature and precipitation on ecosystem properties in tidal saline wetlands Data on interannual variability of seed production, nutrient, and weather for 219 plant species