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1.
Concerns over the loss of biodiversity and ecosystem services in farmland have prompted the development of agri-environment policy measures aimed at reducing farming pressure and maintaining semi-natural habitats in farmed landscapes. However, further knowledge is needed to guarantee successful agri-environment measures implementation. The current study assessed the quantity and the quality of semi-natural habitats in farms across a gradient of farming intensities in two contrasting regions in Ireland. Policy protection seemed fundamental for semi-natural habitats preservation. Habitats not protected by agricultural policy relied on extensive farming and are in danger of disappearing if they are intensified or abandoned. Due to the lack of policy incentives for habitat quality, no correlations were found between farming intensity and share of semi-natural habitats with habitat quality. Therefore, extensive farming and retention of habitats alone may not reverse the decline of farmland quality and biodiverisity and, thus, measures incentivising the environmental quality may be more successful.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01344-6) contains supplementary material, which is available to authorized users.  相似文献   
2.
Regional Environmental Change - The threat of flooding poses a considerable challenge for justice. Not only are more citizens becoming exposed to risk, but they are expected to play increasingly...  相似文献   
3.
ASTM E2137 (Standard Guide for Estimating Monetary Costs and Liability for Environmental Matters, or E2137) is the guidance for developing estimates of future environmental costs. E2137 provides a hierarchy of cost estimation approaches, and expresses an explicit preference for the use of probabilistic cost analysis to develop expected values for environmental costs. Dr. Ram and his colleagues have published an article (Remediation Journal, Autumn 2013) which rejects the use of EV analysis, arguing that while “good in principle” it has little practical value because it is nearly impossible to develop supportable probabilities. The E2137 principles and processes have been used for more than a decade in the context of addressing future environmental costs, yet their view of E2137 renders the standard meaningless. We conclude that the deficiency is not in the ASTM standard, and that when properly constructed, probabilistic analyses can be used to develop expected values with supportable probabilities. ©2015 Wiley Periodicals, Inc.  相似文献   
4.
Detailed hourly precipitation data are required for long-range modeling of dispersion and wet deposition of particulate matter and water-soluble pollutants using the CALPUFF model. In sparsely populated areas such as the north central United States, ground-based precipitation measurement stations may be too widely spaced to offer a complete and accurate spatial representation of hourly precipitation within a modeling domain. The availability of remotely sensed precipitation data by satellite and the National Weather Service array of next-generation radars (NEXRAD) deployed nationally provide an opportunity to improve on the paucity of data for these areas. Before adopting a new method of precipitation estimation in a modeling protocol, it should be compared with the ground-based precipitation measurements, which are currently relied upon for modeling purposes. This paper presents a statistical comparison between hourly precipitation measurements for the years 2006 through 2008 at 25 ground-based stations in the north central United States and radar-based precipitation measurements available from the National Center for Environmental Predictions (NCEP) as Stage IV data at the nearest grid cell to each selected precipitation station. It was found that the statistical agreement between the two methods depends strongly on whether the ground-based hourly precipitation is measured to within 0.1 in/hr or to within 0.01 in/hr. The results of the statistical comparison indicate that it would be more accurate to use gridded Stage IV precipitation data in a gridded dispersion model for a long-range simulation, than to rely on precipitation data interpolated between widely scattered rain gauges.

Implications:

The current reliance on ground-based rain gauges for precipitation events and hourly data for modeling of dispersion and wet deposition of particulate matter and water-soluble pollutants results in potentially large discontinuity in data coverage and the need to extrapolate data between monitoring stations. The use of radar-based precipitation data, which is available for the entire continental United States and nearby areas, would resolve these data gaps and provide a complete and accurate spatial representation of hourly precipitation within a large modeling domain.  相似文献   

5.
Fishing pressure has increased the extinction risk of many elasmobranch (shark and ray) species. Although many countries have established no‐take marine reserves, a paucity of monitoring data means it is still unclear if reserves are effectively protecting these species. We examined data collected by a small group of divers over the past 21 years at one of the world's oldest marine protected areas (MPAs), Cocos Island National Park, Costa Rica. We used mixed effects models to determine trends in relative abundance, or probability of occurrence, of 12 monitored elasmobranch species while accounting for variation among observers and from abiotic factors. Eight of 12 species declined significantly over the past 2 decades. We documented decreases in relative abundance for 6 species, including the iconic scalloped hammerhead shark (Sphyrna lewini) (?45%), whitetip reef shark (Triaenodon obesus) (?77%), mobula ray (Mobula spp.) (?78%), and manta ray (Manta birostris) (?89%), and decreases in the probability of occurrence for 2 other species. Several of these species have small home ranges and should be better protected by an MPA, which underscores the notion that declines of marine megafauna will continue unabated in MPAs unless there is adequate enforcement effort to control fishing. In addition, probability of occurrence at Cocos Island of tiger (Galeocerdo cuvier), Galapagos (Carcharhinus galapagensis), blacktip (Carcharhinus limbatus), and whale (Rhincodon typus) sharks increased significantly. The effectiveness of MPAs cannot be evaluated by examining single species because population responses can vary depending on life history traits and vulnerability to fishing pressure.  相似文献   
6.
Wybong Creek discharges salts into the agriculturally and industrially important Hunter River in New South Wales, Australia. Abrupt increases in salinity occur periodically in the mid-Wybong Creek catchment. In order to understand the processes which cause these abrupt increases, changes in surface and groundwater were investigated. It is shown that salinity increases can be attributed to highly discrete groundwater discharge directly into the river from below. Hourly electrical conductivity data measured in the river showed regular, diurnal electrical conductivity fluctuations of up to 350 μS cm?1. These fluctuations could not be attributed to barometric pressure, temperature, or evapotranspiration. Instead, a similar periodicity in surface water electrical conductivity and groundwater height in nearby groundwater wells was found. Fluctuations were of similar periodicity to the orthotides which cause fluctuations in surface water height and are induced by Earth tides. The geology in the mid-catchment area indicates conditions are optimal for Earth tides to impact groundwater. The reporting of orthotidal changes in water chemistry in this article is believed to be the first of its kind in the scientific literature, with the large fluctuations noted having important implications for water monitoring and management in the catchment. Further research investigating Earth-tide-induced phases of groundwater heights will better constrain the relationships between surface water chemistry and groundwater height.  相似文献   
7.
In ungulates, the rut generally leads to increased intra and interpopulation movements for males. Because movements induce energetic costs and missed feeding opportunities, they could be an indication of male mating effort. We studied space use of 44 male mountain goats (Oreamnos americanus) from three neighboring subpopulations in southeast Alaska, during the rut from 2005 to 2008. Using mixed models and an information theoretic approach with AIC, we analyzed the relationships between individual traits of males and their space use. We found no indication of breeding migration between subpopulations. Distances between individual seasonal ranges were not related to any individual trait. Daily movements, home range sizes, and total distance traveled during the rut did not vary with mass or age of individuals. As such, effects of individual traits on male space use during the rut appear weak and observed space use patterns do not support any of the main mating effort hypotheses.  相似文献   
8.
Purpose: This study collected and analyzed available testing of motor vehicle seat strength in rearward loading by a body block simulating the torso of an occupant. The data were grouped by single recliner, dual recliner, and all belts to seat (ABTS) seats.

Methods: The strength of seats to rearward loading has been evaluated with body block testing from 1964 to 2008. The database of available tests includes 217 single recliner, 65 dual recliner, and 18 ABTS seats. The trends in seat strength were determined by linear regression and differences between seat types were evaluated by Student's t-test. The average peak moment and force supported by the seat was determined by decade of vehicle model year (MY).

Results: Single recliner seats were used in motor vehicles in the 1960s to 1970s. The average strength was 918 ± 224 Nm (n = 26) in the 1960s and 1,069 ± 293 Nm (n = 65) in the 1980s. There has been a gradual increase in strength over time. Dual recliner seats started to phase into vehicles in the late 1980s. By the 2000s, the average strength of single recliner seats increased to 1,501 ± 335 Nm (n = 14) and dual recliner seats to 2,302 ± 699 Nm (n = 26). Dual recliner seats are significantly stronger than single recliner seats for each decade of comparison (P < .001). The average strength of ABTS seats was 4,395 ± 1,185 in-lb for 1989–2004 MY seats (n = 18). ABTS seats are significantly stronger than single or dual recliner seats (P < .001). The trend in ABTS strength is decreasing with time and converging toward that of dual recliner seats.

Conclusions: Body block testing is an quantitative means of evaluating the strength of seats for occupant loading in rear impacts. There has been an increase in conventional seat strength over the past 50 years. By the 2000s, most seats are 1,700–3,400 Nm moment strength. However, the safety of a seat is more complex than its strength and depends on many other factors.  相似文献   

9.
Watershed simulation models such as the Soil & Water Assessment Tool (SWAT) can be calibrated using “hard data” such as temporal streamflow observations; however, users may find upon examination of model outputs, that the calibrated models may not reflect actual watershed behavior. Thus, it is often advantageous to use “soft data” (i.e., qualitative knowledge such as expected denitrification rates that observed time series do not typically exist) to ensure that the calibrated model is representative of the real world. The primary objective of this study is to evaluate the efficacy of coupling SWAT‐Check (a post‐evaluation framework for SWAT outputs) and IPEAT‐SD (Integrated Parameter Estimation and Uncertainty Analysis Tool‐Soft & hard Data evaluation) to constrain the bounds of soft data during SWAT auto‐calibration. IPEAT‐SD integrates 59 soft data variables to ensure SWAT does not violate physical processes known to occur in watersheds. IPEAT‐SD was evaluated for two case studies where soft data such as denitrification rate, nitrate attributed from subsurface flow to total discharge ratio, and total sediment loading were used to conduct model calibration. Results indicated that SWAT model outputs may not satisfy reasonable soft data responses without providing pre‐defined bounds. IPEAT‐SD provides an efficient and rigorous framework for users to conduct future studies while considering both soft data and traditional hard information measures in watershed modeling.  相似文献   
10.
The theory of ecological cognition poses that the brains and behaviour of animals are shaped by the environmental challenges they face in their everyday lives. Site fidelity and homing ability was tested for five species of intertidal rock pool fish by tagging and displacing them to new rock pools at various distances from their ‘home’ rock pools. Three of the species were rock pool specialists whilst the remaining two spend a small proportion of their life in rock pools during early ontogeny. The three specialists showed strong site fidelity with >50 % of individuals found in the same pool 42 days after tagging. In contrast, the non-specialist species showed low fidelity and poor homing abilities. Homing success in the rock pool specialists remained relatively stable as displacement distance increased. The effect of body size on homing ability was species dependent, with only one species showing a significantly greater tendency to home with increasing size.  相似文献   
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