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21.
22.
S. Oldfield 《Plant biology (Stuttgart, Germany)》2019,21(3):380-382
The National Seed Strategy for Rehabilitation and Restoration was developed by a partnership of 12 federal agencies and over 300 non‐federal cooperators in the United States and launched in 2015. Implementation aims to ensure the availability of genetically appropriate native seed for ecological restoration across the country. Ecological restoration is required in response to a wide range of human impacts. The four main goals of the strategy are: identification of seed needs and availability of genetically appropriate seed; research to improve seed production and ecosystem restoration; development of decision support tools for ecological restoration; and communication and outreach. With the increasing occurrence and intensity of extreme weather events including drought and related wild fires, hurricanes and flooding, native seed is increasingly required in large quantities to build ecological resilience. Acceptance of this need will be crucial to implementation of the National Seed Strategy. 相似文献
23.
《Animal : an international journal of animal bioscience》2022,16(11):100657
To predict the impact of climate change on our beef animals and systems, we need a better understanding of how beef cattle traits are affected by varying weather and frequency of extreme events. We analysed the effect of minimum and maximum temperatures and average daily precipitation on a range of important carcass traits, including age at slaughter, cold carcass weight, carcass growth rate and conformation and fat score (N = >1.6 million), as well as calf 200-day live weight and growth rate (N = >270 000), using data from abattoirs across Britain (carcass traits) and calves in Scottish suckler beef herds (live weights and growth). Animals which experienced higher daily maximum and minimum temperatures had slower carcass and calf growth rates. Increased precipitation also led to poorer cold carcass weights, conformation scores, calf 200-day weights and calf growth. We also analysed the effect of frequency of extreme weather events, including heatwaves, cold waves, and dry and wet days. The frequency of heatwaves, dry and wet days were shown to have significant negative effects on almost all traits considered, for example, predicting that an increase in the frequency of heatwaves by 1 day per 100 days of life would reduce cold carcass weights by about 200 g and increase age at slaughter by about 3 days. Results show that varying weather and frequency of extreme weather, across the lifetime of a beef animal, influences traits which affect the potential profit for a beef farmer. These effects may be due to several factors, including direct effects on the animal, as well as feed availability and management decisions made by the farmer. However, there is potential to mitigate negative effects through a range of animal management strategies. 相似文献
24.
Adrian P. Monroe Travis W. Nauman Cameron L. Aldridge Michael S. ODonnell Michael C. Duniway Brian S. Cade Daniel J. Manier Patrick J. Anderson 《Ecology and evolution》2022,12(2)
Ecologically relevant references are useful for evaluating ecosystem recovery, but references that are temporally static may be less useful when environmental conditions and disturbances are spatially and temporally heterogeneous. This challenge is particularly acute for ecosystems dominated by sagebrush (Artemisia spp.), where communities may require decades to recover from disturbance. We demonstrated application of a dynamic reference approach to studying sagebrush recovery using three decades of sagebrush cover estimates from remote sensing (1985–2018). We modelled recovery on former oil and gas well pads (n = 1200) across southwestern Wyoming, USA, relative to paired references identified by the Disturbance Automated Reference Toolset. We also used quantile regression to account for unmodelled heterogeneity in recovery, and projected recovery from similar disturbance across the landscape. Responses to weather and site‐level factors often differed among quantiles, and sagebrush recovery on former well pads increased more when paired reference sites had greater sagebrush cover. Little (<5%) of the landscape was projected to recover within 100 years for low to mid quantiles, and recovery often occurred at higher elevations with cool and moist annual conditions. Conversely, 48%–78% of the landscape recovered quickly (within 25 years) for high quantiles of sagebrush cover. Our study demonstrates advantages of using dynamic reference sites when studying vegetation recovery, as well as how additional inferences obtained from quantile regression can inform management. 相似文献
25.
X. Zhang J. Halder R.P. White D.J. Hughes Z. Ye C. Wang R. Xu B. Gan B.D.L. Fitt 《The Annals of applied biology》2014,164(3):384-395
To estimate potential impact of climate change on wheat fusarium ear blight (FEB), simulated weather for the A1B climate change scenario was input into a model for estimating FEB in central China. In this article, a logistic weather‐based regression model for estimating incidence of wheat FEB in central China was developed, using up to 10 years (2001–2010) of disease, anthesis date and weather data available for 10 locations in Anhui and Hubei provinces. In the model, the weather variables were defined with respect to the anthesis date for each location in each year. The model suggested that incidence of FEB is related to number of days of rainfall in a 30‐day period after anthesis and that high temperatures before anthesis increase the incidence of disease. Validation was done to test whether this relationship was satisfied for another five locations in Anhui province with FEB data for 4–5 years but no nearby weather data, using simulated weather data obtained employing the regional climate modelling system PRECIS. How climate change may affect wheat anthesis date and FEB in central China was investigated for period 2020–2050 using wheat growth model Sirius and climate data simulated using PRECIS. The projection suggested that wheat anthesis dates will generally be earlier and FEB incidence will increase substantially for most locations. 相似文献
26.
MICHAEL L. SCHUMMER RICHARD M. KAMINSKI ANDREW H. RAEDEKE DAVID A. GRABER 《The Journal of wildlife management》2010,74(1):94-101
ABSTRACT Research on effects of key weather stimuli influencing waterfowl migration during autumn and winter is limited. We investigated relationships between changes in relative abundances of mallard (Anas platyrhynchos) and other dabbling ducks (Anas spp.) and weather variables at midlatitude locations in North America. We used waterfowl survey data from Missouri Conservation Areas and temperature and snow cover data from the Historical Climatology Network to evaluate competing models to explain changes in relative abundance of ducks in Missouri, USA, during autumn-winter, 1995–2005. We found that a cumulative weather severity index model (CumulativeWSI; calculated as mean daily temp - degrees C + no. of consecutive days with mean temp ≤ 0° C + snow depth + no. of consecutive days with snow cover) had the greatest weight of evidence in explaining changes in relative abundance of ducks. We concluded the CumulativeWSI reflected current and cumulative effects of ambient temperatures on energy expenditure by ducks, and snow cover and wetland icing, on food availability for ducks. The CumulativeWSI may be useful in determining potential changes in autumn-winter distributions of North American waterfowl given different climate change projections and associated changes in habitat conservation needs. Future investigations should address interactions between CumulativeWSI and landscape habitat quality, regional waterfowl populations, hunter harvest, and other anthropogenic influences to increase understanding of waterfowl migration during autumn-winter. 相似文献
27.
Abstract: Synchrony is an important component of wildlife population dynamics because it describes spatial pattern in temporal population fluctuations. The strength and spatial extent of synchrony can provide information about the extrinsic and intrinsic forces that shape population structure. Wild turkey (Meleagris gallopavo silvestris) populations undergo annual fluctuations, possibly due to variation in weather during the reproductive season. To determine if spring weather plays a role in synchronizing wild turkey populations, we used a modified Mantel-type spatial autocorrelation procedure to measure the synchrony in fall wild turkey harvest data collected in 443 townships from 1990 to 1995 and compared this to the pattern of synchrony in spring weather variables (May rainfall and temp) over the same period. We measured correlation using Spearman correlation coefficients between the total fall harvests from 1990 to 1995 for each pair of townships, and sorted pairs into 6 50-km distance intervals. We calculated a mean correlation coefficient for each interval and estimated its P-value using resampling. We found moderately significant synchrony in the fall harvest (rs = 0.12-0.34, P < 0.008) among township pairs <150 km apart, but no significant synchrony beyond this distance. In contrast, both May temperature (r = 0.82-0.90, P < 0.001) and rainfall (r = 0.49-0.76, P < 0.001) were strongly synchronized across all 6 distance intervals. Visual inspection of time series in the wild turkey fall harvest suggests that populations may be synchronized in some years when weather promotes high reproductive success (i.e., a synchronized growth peak) and asynchronous in other years. Knowledge of the spatial dynamics of wild turkey populations will aid wildlife managers in estimating population change, setting harvest quotas, and managing habitat. 相似文献
28.
Stochastic simulation of daily air temperature and precipitation from monthly normals in North America north of Mexico 总被引:2,自引:0,他引:2
A simple, stochastic daily temperature and precipitation generator (TEMPGEN) was developed to generate inputs for the study
of the effects of climate change on models driven by daily weather information when climate data are available as monthly
summaries. The model uses as input only 11 sets of monthly normal statistics from individual weather stations. It needs no
calibration, and was parameterized and validated for use in Canada and the continental United States. Monthly normals needed
are: mean and standard deviation of daily minimum and maximum temperature, first and second order autoregressive terms for
daily deviations of minimum and maximum temperatures from their daily means, correlation of deviations of daily minimum and
maximum temperatures, total precipitation, and the interannual variance of total precipitation. The statistical properties
and distributions of daily temperature and precipitation data produced by this generator compared quite favorably with observations
from 708 stations throughout North America (north of Mexico). The algorithm generates realistic seasonal patterns, variability
and extremes of temperature, precipitation, frost-free periods and hot spells. However, it predicts less accurately the daily
probability of precipitation, extreme precipitation events and the duration of extreme droughts. 相似文献
29.
Radio-telemetric monitoring of dispersing stag beetles: implications for conservation 总被引:2,自引:0,他引:2
Migratory movements of the endangered stag beetles Lucanus cervus (18 males, 38 females) were monitored radio-telemetrically for three reproductive periods (2003–2005). The aim of the study was to estimate the migratory range of free-ranging individuals as a measure of connectivity among neighbouring populations for future conservation measures. Miniature transmitters of c . 350 mg (battery life: 10–15 days) were attached externally to the pronotum. Transmitter/beetle mass ratio was 12.8% on average (7.1–28.0%). Male dispersal behaviour consisted of frequent flights directed to sites with reproductive females and rarely of on-ground movement. Total displacement distance recorded was up to 2065 m, the maximum distance of a single flight being 1720 m. Flights always began at elevated structures such as trees and shrubs and took place in an air temperature range of 11–27°C. Within this range, temperature did not influence flight distance. Female dispersal behaviour consisted mostly of a single flight, followed by mating and consequent ground movements towards oviposition sites. Total displacement distance recorded was up to 762.6 m, the maximum distance of a single flight being 701 m. Climatic constraints of flights were the same as in males. Modelling the dispersal behaviour suggests that about 1% of males are capable of maintaining gene flux among nest sites within a radius of about 3 km. However, the colonization of new nest sites depends on the dispersal ability of females and amounts to less than 1 km. Thus, isolated populations (distance to the next population greater than 3 km) have an increased probability of local extinction. 相似文献
30.
Arnaud Da Silva Mihai Valcu Bart Kempenaers 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1667)
Artificial night lighting is expanding globally, but its ecological consequences remain little understood. Animals often use changes in day length as a cue to time seasonal behaviour. Artificial night lighting may influence the perception of day length, and may thus affect both circadian and circannual rhythms. Over a 3.5 month period, from winter to breeding, we recorded daily singing activity of six common songbird species in 12 woodland sites, half of which were affected by street lighting. We previously reported on analyses suggesting that artificial night lighting affects the daily timing of singing in five species. The main aim of this study was to investigate whether the presence of artificial night lighting is also associated with the seasonal occurrence of dawn and dusk singing. We found that in four species dawn and dusk singing developed earlier in the year at sites exposed to light pollution. We also examined the effects of weather conditions and found that rain and low temperatures negatively affected the occurrence of dawn and dusk singing. Our results support the hypothesis that artificial night lighting alters natural seasonal rhythms, independently of other effects of urbanization. The fitness consequences of the observed changes in seasonal timing of behaviour remain unknown. 相似文献