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331.
John Dover Tim Sparks Sue Clarke Kay Gobbett Sarah Glossop 《Agriculture, ecosystems & environment》2000,80(3):179
Green lanes are unmetalled tracks between fields of variable width, which may be sunk below or raised above field level, and bounded on both sides by ‘grass’ banks, hedgerows or dry-stone walls. In the UK they have no unique planning status and have been overlooked as discrete landscape elements. Green lanes were surveyed for butterflies in 1997 on lowland arable farmland on the Trafford/north Cheshire border (Warburton) and on upland grassland in the Yorkshire Dales (Ribble Valley). At the lowland site the green lanes were bounded by vegetation and were compared with grass banks and single hedgerow field boundaries; at the upland farm, the green lanes were bounded by dry-stone walls and were compared with grass banks and single dry-stone walls. Data from earlier work on a largely arable farm (Manydown) in Hampshire in 1987 and 1988 were re-analysed to make comparisons between a green lane, the rides and glades of two coppiced woodlands, and the grass banks and single hedgerows surrounding arable fields. Green lanes, whether bounded by vegetation or stone were superior to other common farmland biotopes with the exception of woodland, in terms of both butterfly abundance and species richness.Multiple regression of the Warburton data indicated the importance of green lanes, adjacent habitat type, and nectar sources for species richness and butterfly abundance. The interior of green lanes had lower windspeeds, and more bramble nectar sources than hedgerows or grass banks. By their nature they occupy a larger area of uncropped land, and are subject to a reduced disturbance regime and reduced inputs of agrochemicals and fertilisers. Their value as biodiversity reservoirs in intensively managed land is likely to be high. 相似文献
332.
IntroductionIntheFifthFrameworkProgrammeoftheEuropeanCommission(EC,1999),under“toolsforsustainabledevelopment”,therewasrecentlyaspecialcallforproposalsfor“Technologiesforsustainableplantandanimalproduction:buildingblocksforimprovement(forsmallscaleorenvir… 相似文献
333.
Pieter Bloemen Tim Reeder Chris Zevenbergen Jeroen Rijke Ashley Kingsborough 《Mitigation and Adaptation Strategies for Global Change》2018,23(7):1083-1108
Worldwide, an increase in flood damage is observed. Governments are looking for effective ways to protect lives, buildings, and infrastructure. At the same time, a large investment gap seems to exist—a big difference between what should necessarily be done to curb the increase in damage and what is actually being done. Decision-makers involved in climate adaptation are facing fundamental (so-called deep) uncertainties. In the course of time, the scientific community has developed a wide range of different approaches for dealing with these uncertainties. One of these approaches, adaptation pathways, is gaining traction as a way of framing and informing climate adaptation. But research shows that “very little work has been done to evaluate the current use of adaptation pathways and its utility to practitioners and decision makers” (Lin et al. 2017, p. 387). With this paper, the authors, as action researchers and practitioners involved in two of the world’s largest real-life applications of this approach in flood risk management, aim to contribute to filling in that gap. Analysis of the experience in the United Kingdom and the Netherlands in long-term planning in flood risk management shows that the adaptation pathways approach is effective in keeping decision processes going forward, to the final approval of a long-term plan, and helps increase awareness about uncertainties. It contributes to political support for keeping long-term options open and motivates decision-makers to modify their plans to better accommodate future conditions. When it comes to implementing the plans, there are still some major challenges, yet to be addressed, amongst others: the timely detection of tipping points in situations with large natural variability, the inclusion of measures that prepare for a switch to transformational strategies, and the retention of commitment of regional and local authorities, non government organizations, and the private sector, to climate adaptation as national policies move from blueprint planning to adaptive plans. In delivering this feedback, the authors hope to motivate the scientific community to take on these challenges. 相似文献
334.
Van Boeckel TP Prosser D Franceschini G Biradar C Wint W Robinson T Gilbert M 《Agriculture, ecosystems & environment》2011,141(3-4):373-380
Domestic ducks are considered to be an important reservoir of highly pathogenic avian influenza (HPAI), as shown by a number of geospatial studies in which they have been identified as a significant risk factor associated with disease presence. Despite their importance in HPAI epidemiology, their large-scale distribution in monsoon Asia is poorly understood. In this study, we created a spatial database of domestic duck census data in Asia and used it to train statistical distribution models for domestic duck distributions at a spatial resolution of 1 km. The method was based on a modelling framework used by the Food and Agriculture Organisation to produce the Gridded Livestock of the World (GLW) database, and relies on stratified regression models between domestic duck densities and a set of agro-ecological explanatory variables. We evaluated different ways of stratifying the analysis and of combining the prediction to optimize the goodness of fit of the predictions. We found that domestic duck density could be predicted with reasonable accuracy (mean RMSE and correlation coefficient between log-transformed observed and predicted densities being 0.58 and 0.80, respectively), using a stratification based on livestock production systems. We tested the use of artificially degraded data on duck distributions in Thailand and Vietnam as training data, and compared the modelled outputs with the original high-resolution data. This showed, for these two countries at least, that these approaches could be used to accurately disaggregate provincial level (administrative level 1) statistical data to provide high resolution model distributions. 相似文献
335.
As with many farmland bird species, the house sparrow Passer domesticus is declining in Europe, mainly due to intensification of agriculture reducing nest sites and food supplies. During 2002–2005,
we studied the population size and nest site characteristics of house sparrows breeding within white stork Ciconia ciconia nests in a large area of agricultural landscape within western Poland. To explain sparrow density within stork nests, we
examined characteristics of white stork nests (position, age, productivity) and the farm type around the nest. House sparrow
density was greatest in the longest established (and hence larger) white stork nests located on traditionally managed farms.
Two recent changes appear to have adverse effects on house sparrows. The first is the intensification of farming and the second
is active management of white stork nests on electric poles to reduce nest size and thus avoid both disruption to the electrical
supply and electrocution of white storks. Because the white stork has such a high profile in Poland, there are numerous schemes
to conserve and enhance this species. In conclusion, we clearly show that protecting one species can have valuable, although
unplanned, benefits to another species of conservation interest, the house sparrow. 相似文献
336.
David J.T. Douglas Juliet A. Vickery Tim G. Benton 《Agriculture, ecosystems & environment》2010,135(1-2):127-131
Managing arthropod populations on farmland for conservation purposes, such as food resources for declining farmland birds, requires information on the way distributions vary between crop types, for example under varying sowing regimes. In this study arthropods were sampled during one summer from fields of winter-sown and spring-sown barley. The relative timing of crop development had a strong influence on arthropod abundance between crop types, with winter barley supporting significantly higher abundance of total counts and many individual orders in early summer, but the reverse being the case in late summer. Fields of both crop types that received higher herbicide inputs showed reduced arthropod counts. 相似文献
337.
Colleen Jacob Tim McDaniels Scott Hinch 《Mitigation and Adaptation Strategies for Global Change》2010,15(8):859-876
This paper provides a culturally-informed understanding of the impacts of climate change on a highly important subsistence
activity that has been practiced by First Nations of central British Columbia for thousands of years. The paper begins with
a review of the science regarding sockeye salmon and climate change. It discusses harvest patterns, and how the timing of
runs has changed. A survey was conducted by the first author regarding St’át’imc traditional fishing at a historic site on
the Fraser River, in 2005. The results show that the impacts of climate change are apparent to those conducting traditional
fishing practices, in terms of changed timing and abundance of salmon runs. These perceptions fit closely with the information
available from scientists and management agencies. These changes are highly problematic for the St’át’imc, in that the preservation
method (drying) is tied to seasonal weather patterns. The whole cultural setting, and the relevance of salmon for subsistence
would be highly altered by climate change that leads to changes in the timing and abundance of sockeye salmon. The paper discusses
mitigation and adaptation alternatives, but also indicates the scope of these seem limited, given the resource systems and
the context of these activities. 相似文献
338.
Pop-up satellite archival tags were deployed onto four wahoo during 2006 in the western North Atlantic (~26.5°N, 79.3°W), providing movement, depth, and temperature data collected over a total of 198?days. Straight-line distances between tag deployment and pop-off positions ranged from 162.5 to 1,960.0?km. Wahoo spent >90?% of their time in water <200?m, and >90?% of their time in water between 17.5 and 27.5?°C. Three fish made regular trips to depths >200?m. All four fish had significantly different depth distributions between the dark and light periods (Kruskal–Wallace test, p?0.001). The median mean depth for all fish combined was 29.7?m during the dark period (Q1?=?18.8?m, Q3?=?46.2?m) and 50.7?m during the light period (Q1?=?22.3?m, Q3?=?112.3?m). This research improves an otherwise poor understanding of wahoo movements and depth/temperature distributions and suggests potential interactions with other members of the pelagic fish community, many of which are commercially important and either fully or over-exploited. 相似文献
339.
Tom Hart Richard Mann Tim Coulson Nathalie Pettorelli Phil Trathan 《Marine Biology》2010,157(7):1543-1553
Recording the activity of animals as they migrate or forage has proven hugely advantageous to understanding how animals use
their environment. Where animals cannot be directly observed, the problem remains of how to identify distinct behaviours that
represent an animal’s decision-making process. An excellent example of this problem is that of foraging penguins, which travel
to sea to find prey to provision their young. Without direct sampling of the prey field, we cannot calibrate patterns of movement
with prey capture, and therefore we cannot determine how different activities link to decision-making. To overcome this, we
use a hidden markov model (HMM), which is a machine-learning technique that seeks to identify the underlying states of a system
from observable outputs. We apply HMM to determine classes of behaviour from repetitive dives. We take dive data from 103
breeding macaroni penguins at Bird Island, South Georgia, for which we have measures of weight gain over a trip. We identify
two classes of behaviour; those of short-shallow and long-deep dives. Using these two behaviours, we calculate the transition
probabilities between these states and analyse these data to determine what predicts variation in the transition probabilities.
We found that the stage of reproduction during a season, the sex and year of an individual influenced the probability of transition
between long-deep and short-shallow sequential dives. We also found differences in the hourly transition rates between the
four reproductive stages (incubation, broodguard, crèche and premoult) over a daily cycle. We conclude that this application
of HMMs for behavioural switching is potentially useful for other species and other types of recorded behaviour. 相似文献
340.
Stefan Lüpold Tim R. Birkhead David F. Westneat 《Behavioral ecology and sociobiology》2012,66(12):1607-1617
Many reproductive traits, including ejaculate characteristics, usually show remarkable seasonal variation, but the potential for such dynamics in sperm morphology has been overlooked. Several studies have revealed high within-male repeatability in sperm morphology, but samples have typically been collected within a few hours or days, and the consistency of sperm morphology over longer periods remains unexplored. Here, we tested whether ejaculate traits, including sperm morphology, sperm number, and sperm velocity, exhibit seasonal phenotypic plasticity in a long-lived seasonal breeder, the red-winged blackbird (Agelaius phoeniceus). We found absolute and/or relative flagellum length and sperm velocity to increase across the season, whereas sperm numbers within ejaculates declined. Sperm morphological traits were further positively associated with harem size or the total number of offspring that fledged in each male’s territory, suggesting that sperm morphology is likely to be linked to male reproductive quality. The underlying mechanisms of these patterns of seasonal variation remain unresolved, but we discuss our results in the context of dynamics of reproductive hormones, testicular structures and function, and reproductive behavior. 相似文献