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1.
Capsule Set-aside schemes have allowed breeding Woodlarks to colonize farmland, but heathland and forestry habitats remain the stronghold.

Aims To determine which habitats provide the best conditions for breeding Woodlarks and whether a buffer effect is operating, with density increasing faster in the poorer quality habitat as the population grows.

Methods Habitat colonization was examined and breeding success compared among heathland, clear-felled and young conifer plantations, and farmland set-aside.

Results Woodlarks on heathland and forestry habitats had similar clutch sizes and nesting success, but clutch sizes may be lower on farmland. Heathland was recolonized when population density was low in forest habitats, while farmland was colonized when density was increasing, and areas close to forest were preferentially occupied. Woodlarks breeding on farmland preferred set-aside stubbles to other field types.

Conclusion Forestry and heathland habitats are similar in quality for breeding Woodlarks, with no evidence for a buffer effect. Farmland set-aside may be suboptimal but the area available is much greater than the area of forest or heathland, and could therefore make a significant contribution to the conservation of the Woodlark population. However, set-aside should not be seen as an alternative to the conservation of forest and heathland.  相似文献   

2.
目的 对我国各地区民营医院的发展现状进行评价,为推动民营医院发展、民营医疗产业集聚的形成提供参考依据。方法 基于卫生资源集聚度的评价方法,分析我国各地区民营医院集聚度,以及与人口、经济和公立医院集聚度的相关性。结果 (1)经济集聚度较人口集聚度与民营医院集聚度的相关性更大。(2)我国少数地区民营医院集聚度与公立医院集聚度接近,绝大部分地区民营医院集聚度较低、规模偏小。(3)我国民营医院市场中综合医院比重较大,专科医院在经济发达地区集聚度较高。结论 民营医疗产业集聚速度缓慢、规模偏小,亟需政府积极引导,加快民营医疗产业集聚,发挥市场有效配置卫生资源的作用。  相似文献   

3.
The effects of selective logging and other types of forest exploitation on bird communities are often studied latitudinally, i.e. a contemporaneous comparison of disturbed and pristine areas. Such an approach assumes that before disturbance those areas were equivalent. By comparing communities at a single site before and after disturbance, a so called longitudinal approach does not make that assumption but such studies can be resource intensive. In this study we adopt a latitudinal approach to explore the effects of disturbance on birds, but pay specific attention to whether natural geographically-based variation in the forest ecosystem may be a major contributory factor equal to, or greater than, effects of disturbance. Bird census data were collected from two Indonesian islands, Sumba and Buru. On Sumba the differences between habitat types in terms of species richness, species accumulation rates, and numbers of birds were swamped by simple site differences between the forest blocks sampled. On Buru, disturbed areas were more diverse than mature forest but it was still not possible to discount the effects of natural variation between forest areas. Although the islands support bird faunas which are rather similar in size and origin, local species diversities and abundances were significantly greater on Sumba. Substituting space for time is a common strategy in ecological research but the results of such studies should be viewed with caution.  相似文献   

4.
Abstract

Pest problems involve people who value a resource affected by a pest that is managed by people, ideally the same as those who value the resource. Management that is not inclusive of pests, resources, people, and their interactions usually fails. Mammalian pests in New Zealand are of two sorts: those that are pests in their native land (usually r-strategists), and those that are not (usually K-strategists). The impact on New Zealand resources of r-strategists tends to be periodic and acute when their densities are high. Control works best against them when it is applied once densities become intolerable, or once such densities can be predicted. The impact of K-strategists is more stable but is chronic. Control operations against them need to be sustained and regular to retain the stability of the pest-resource interaction, but to drive it in favour of the resource. The basic strategies to deal with the impact of pests are: those for which a one-off management action has a permanent benefit (e.g., eradication); those that require ongoing action to gain a permanent benefit (e.g., sustained control); and those for which no management action is possible or justified. Idealist and cynical approaches to pest policies are discussed and rejected in favour of a pragmatic policy.  相似文献   

5.
The distribution pattern and competition of insects exploiting Camellia japonica flowers were studied in Tokyo, central Japan, to understand how their distributions are determined. Dasiops sp. of Lonchaeidae (Diptera) exploited flower buds and showed random distribution, whereas Drosophila unipectinata, D. oshimai and D. lutescens of Drosophilidae (Diptera) and Epuraea commutata of Nitidulidae (Coleoptera) exploited fully opened, late and fallen flowers and showed aggregated distribution. From the distribution pattern, it is assumed that Dasiops sp. has clutches of single egg whereas drosophilid and nitidulid species have clutches of more than one egg. In resource supplementary experiments, body size of drosophilid flies increased if resources were supplemented, although their survival is assumed to be unaffected. However, their body size did not decrease with increase of larval density in resource patches. It is therefore unclear whether resource competition occurs among drosophilid flies in Camellia flowers in nature. From the present and previous studies, it is assumed that aggregation (or production of clutches of more than one egg) is related to the use of fermenting or decayed resources; aggregation might increase larval survival and/or performance under the presence of molds or microorganisms.  相似文献   

6.
Abstract

Two advantages could be gained by developing multi-species control by aerial baiting. It should assist pest managers to achieve sustainable resource management by improving the efficiency of operations; and it should reduce the likelihood of unwanted ecological side-effects (such as prey-switching) that sometimes follow when pest species are controlled individually. The technology to achieve efficient multi-species control is already well advanced, aided particularly by the refinement of aerial control of possums and by the development of baits for individual species. More effort will, however, be required to develop predictive models for planning the integration of multi-species control with conventional single-species control, and for predicting the ecological effects of such intervention.  相似文献   

7.
Species introductions are among the most pervasive types of disturbance, seriously affecting island biota and ecosystem dynamics. The management of introduced generalist species, which may live in a wide range of environmental conditions, can be particularly difficult and is a major challenge for the conservation of native insular species. Boa constrictor was introduced onto Cozumel Island, Mexico, in 1971. The introduction of this generalist predator has affected negatively the native species (many of them endemic to the island) on which the boa feed. It is important to determine temporal variation in boa abundance, the areas of the island in which boas live, and the vegetation types they use in order to develop management strategies to reduce boa pressure on the native biota. We used nocturnal road transect sampling and occasional boa encounters during field work, to estimate boa distribution, abundance and habitat use, taking into account its spatiotemporal patterns on Cozumel Island. This study confirms that Boa constrictor is well established, widespread, and abundant on the island. Our results show that boas are distributed throughout Cozumel, in all vegetation types and geographical regions. Overall, there were 0.11 ± 0.03 boa/10 km road transect. There were no significant spatiotemporal differences in boa activity (time of day) and abundance (monthly, seasonally, by vegetation types or regions of the island). According to the habitat use analysis, there were, however, fewer boas than expected in the subdeciduous tropical forest we sampled and in the central-northern region of the island, which coincide with areas inhabited by humans. There were more boas in areas uninhabited by humans, and there was a tendency towards a greater proportion of dead boas in inhabited areas and live boas in uninhabited areas. Cozumel boas are habitat generalists, which are affected by human induced mortality in inhabited areas. There is a vast area uninhabited by humans, with natural vegetation, on the island where boas have suitable habitats available for their continuous existence on Cozumel. This situation, and the adaptability of the boa, makes the control or eradication of this introduced species a critical conservation challenge.  相似文献   

8.
Purpose

In 1995, the original method for assessing the impact category abiotic resource depletion using abiotic depletion potentials (ADPs) was published. The ADP of a resource was defined as the ratio of the annual production and the square of the ultimate (crustal content based) reserve for the resource divided by the same ratio for a reference resource (antimony (Sb)). In 2002, ADPs were updated based on the most recent USGS annual production data. In addition, the impact category was sub-divided into two categories, using two sets of ADPs: the ADP for fossil fuels and the ADP for elements; in this article, we focus on the ADP for elements. Since then, ADP values have not been updated anymore despite the availability of updates of annual production data and also updates of crustal content data that constitute the basis of the ultimate reserves. Moreover, it was known that the coverage of elements by ADPs was incomplete. These three aspects together can affect relative ranking of abiotic resources based on the ADP. Furthermore, dealing with annually changing production data might have to be revisited by proposing new calculation procedures. Finally, category totals to calculate normalized indicator results have to be updated as well, because incomplete coverage of elements can lead to biased results.

Methods

We used updated reserve estimates and time series of production data from authoritative sources to calculate ADPs for different years. We also explored the use of several variations: moving averages and cumulative production data. We analyzed the patterns in ADP over time and the contribution by different elements in the category total. Furthermore, two case studies are carried out applying two different normalization reference areas (the EU 27 as normalization reference area and the world) for 2010.

Results and discussion

We present the results of the data updates and improved coverage. On top of this, new calculation procedures are proposed for ADPs, dealing with the annually changing production data. The case studies show that the improvements of data and calculation procedures will change the normalized indicator results of many case studies considerably, making ADP less sensitive for fluctuating production data in the future.

Conclusions

The update of ultimate reserve and production data and the revision of calculation procedures of ADPs and category totals have resulted in an improved, up-to-date, and more complete set of ADPs and a category total that better reflects the total resource depletion magnitude than before. An ADP based on the cumulative production overall years is most in line with the intent of the original ADP method. We further recommend to only use category totals based on production data for the same year as is used for the other (emission-based) impact categories.

  相似文献   

9.
BackgroundTargeting interventions to areas that have recently experienced cases of disease is one strategy to contain outbreaks of infectious disease. Such case-area targeted interventions (CATI) have become an increasingly popular approach for dengue control but there is little evidence to suggest how precisely targeted or how recent cases need to be, to mount an effective response. The growing interest in the development of prophylactic and therapeutic drugs for dengue has also given new relevance for CATI strategies to interrupt transmission or deliver early treatment.Methods/Principal findingsHere we develop a patch-based mathematical model of spatial dengue spread and fit it to spatiotemporal datasets from Singapore. Simulations from this model suggest CATI strategies could be effective, particularly if used in lower density areas. To maximise effectiveness, increasing the size of the radius around an index case should be prioritised even if it results in delays in the intervention being applied. This is partially because large intervention radii ensure individuals receive multiple and regular rounds of drug dosing or vector control, and thus boost overall coverage. Given equivalent efficacy, CATIs using prophylactic drugs are predicted to be more effective than adult mosquito-killing vector control methods and may even offer the possibility of interrupting individual chains of transmission if rapidly deployed. CATI strategies quickly lose their effectiveness if baseline transmission increases or case detection rates fall.Conclusions/SignificanceThese results suggest CATI strategies can play an important role in dengue control but are likely to be most relevant for low transmission areas where high coverage of other non-reactive interventions already exists. Controlled field trials are needed to assess the field efficacy and practical constraints of large operational CATI strategies.  相似文献   

10.
Abstract

This paper reviews and examines the development of the concept of entry control policies in fisheries management. With renewed expectations for U. S. fisheries surrounding the recent enactment of legislation that extends jurisdiction over living resources within 200 mi, optimal management of an open‐access resource becomes an increasingly important public policy problem. The paper reviews alternative entry control schemes and criteria in order to evaluate their effectiveness and suggests ways in which limited entry could be implemented incrementally. It is argued that the appropriate combination of alternative limited‐entry mechanisms should take into account regional variables that affect the feasibility of entry controls for each particular fishery. It is also postulated that exploitation of an open‐access resource such as a fishery implies certain types of political behavior and outcomes that are analogous to economic behavior and outcomes in a common‐property resource environment. These characteristics of an openaccess resource, along with physical characteristics, tend to inhibit severely the rate of development of clearly defined property rights that would enhance the overall efficiency of the resource industry. The rate of development of property rights in an open‐access resource is a function of the cost of defining and enforcing these rights. The paper urges further identification and analysis of these “transactions costs,” which are largely a function of the political environment.  相似文献   

11.
《Plains anthropologist》2013,58(96):109-123
Abstract

Interaction plays a central role in archaeological interpretations, yet it has remained theoretically underdeveloped and has often been misused. A framework for dealing with interaction is presented, consisting of: 1) ultimate adaptive conditions for interaction; 2) specific reasons for various types of interaction; 3) modifications of interaction due to aspects of the social matrix; 4) interaction mechanisms; and 5) the artifact patterns resulting from all of these factors. It is clear that “interaction” cannot be treated as a monolithic phenomenon; rather there are many types of interaction with many different outcomes for artifact patterning. The transition from the Paleo-Indian to Archaic stages is analyzed within this framework, and it is suggested that in the simplified interaction context of generalized hunter/ gatherers the size of interaction networks is largely a function of resource reliability and the relative need to maintain subsistence-related alliances between bands.  相似文献   

12.
ABSTRACT

Parus major and Parus caeruleus palmensis have some song types in common. They consist of whistled element-types in different frequency ranges. Both species show territorial reactions to playback of the song-types belonging to the other species. P.c. palmensis does not share any songtypes with Central European Parus caeruleus. This is confirmed by playback experiments with the different song types, which do not elicit any territorial behaviour. The songs of P.c. palmensis also differ from those of blue tits from any other Canary Island. They may be derived from contact calls of the Lanzarote population. They have been developed by young birds that had not yet learnt their songs when they colonized La Palma from Lanzarote without reaching any of the other Canary Islands. It is suggested that the uniform song repertoire was developed by adapting the already learned contact calls to each other. The similarities to song types of P. major are due to convergence rather than character displacement. All other Canary Island tit populations share the main features of their songs, which are characterized by quick frequency changes. It seems most likely that these islands have been colonized by birds which had already learnt their songs. Differences in song repertoires are mainly caused by drift events which happen to occur because of population bottlenecks during the colonization process.  相似文献   

13.
BackgroundAtrial fibrillation is a large and growing burden across all types of healthcare. Both incidence and prevalence are expected to double in the next 20 years, with huge impact on hospital admissions, costs and patient quality of life. Patient wellbeing determines the management strategy for atrial fibrillation, including the use of rhythm control therapy and the clinical success of heart rate control. Hence, evaluation of quality of life is an emerging and important part of the assessment of patients with atrial fibrillation. Although a number of questionnaires to assess quality of life in atrial fibrillation are available, a comprehensive overview of their measurement properties is lacking.InterpretationGiven the low ratings for many measurement properties, no single questionnaire can be recommended, although AFEQT performed strongest. Further studies to robustly assess reliability, validity and responsiveness of AF-specific quality of life questionnaires are required. This review consolidates the current evidence for quality of life assessment in patients with atrial fibrillation and identifies priority areas for future research.  相似文献   

14.
Capsule?Bird species richness and (for most species) abundance were positively related to the extent of shrub cover at the interface between conifer plantations and moorland, but it appears that responses to shrub development vary between different bird guilds.

Aims?To assess the bird assemblages in both winter and breeding seasons at the interface between managed conifer plantations and open moorland, where that interface had been restructured to include a mosaic of shrubs and open ground.

Methods?Timed point counts were used to sample the birds at restructured plantation – moorland interface areas and also in neighbouring plantations (post- and pre-thicket age classes) and neighbouring moorland. Associations between species richness and abundances with measures of shrub cover and composition were assessed using GLMMs.

Results?A total of 60 bird species were recorded including 29 on lists of conservation concern, most of which were associated with shrub interface habitats. Species richness and, for most species, abundance were positively related to the extent of shrub cover. Positive relationships between shrub cover in interface areas and the abundance of some species in neighbouring plantations and open moorland suggested a resource subsidy to birds in neighbouring habitats. In contrast, some birds tended to be less abundant in plantations next to areas with more shrub cover. These species were more abundant in the shrub itself, suggesting redistribution by species with a preference for early successional shrub habitats.

Conclusions?The long-term management of shrub, especially with regard to successional development, is a challenging aspect of forest and landscape management that deserves further study.  相似文献   

15.
Background: Water resources are of fundamental importance to society, and are better managed by stakeholders who understand resource issues. Gaining such knowledge is a lifelong process best begun at an early age and best supported by educational approaches integrating across science, technology, engineering and mathematics (STEM). Research scientists can bring resource education to young audiences through children’s books and curricula that emphasise and integrate across STEM principals.

Aims: To encourage empathy for the environment in younger students, researchers at the Niwot Ridge Long Term Ecological Research site have developed a children’s book series and methods for training teachers in water science education.

Methods: Children’s books in the My Water series are paired with curricula, hands-on learning kits, teacher development training and dissemination of materials through school districts to further water science education.

Results: Thousands of children and educators have received training through the My Water book series, and a more broadly focused, federally funded Schoolyard Children’s Book Series has grown out of these efforts towards water resource education.

Conclusions: Children’s books and curricula that integrate STEM principals can play a key role in the development of environmental empathy and lifelong learning to support resource management.  相似文献   

16.
Abstract

The soft-bottom biota of subtidal areas of Paterson Inlet, Stewart Island, is described on the basis of data collected during cruises (1977 and 1979) in search of Braichiopoda. Two associations are recognised within the areas sampled, and their structure is compared with that of soft-bottom biotas elsewhere in New Zealand. The widespread occurrence of patch-forming bryozoans (especially Cinctipora elegans) on sandy gravels on the southern New Zealand shelf IS recognised.  相似文献   

17.
BackgroundLeptospirosis is a neglected zoonosis affecting animals and humans caused by infection with Leptospira. The bacteria can survive outside of hosts for long periods of time in soil and water. While identification of Leptospira species from human cases and animal reservoirs are increasingly reported, little is known about the diversity of pathogenic Leptospira species in the environment and how surveillance of the environment might be used for monitoring and controlling disease.ConclusionsThis study reports the presence of pathogenic Leptospira in the peri-domestic environment of households in three community types and the differences in Leptospira diversity at the community level. Systematic environmental surveillance of Leptospira can be used for detecting changes in pathogen diversity and to identify and monitor contaminated areas where an increased risk of human infection exists.  相似文献   

18.
《Endocrine practice》2010,16(1):118-129
ObjectiveTo provide a clinical update on Graves’ hyperthyroidism and pregnancy with a focus on treatment with antithyroid drugs.MethodsWe searched the English-language literature for studies published between 1929 and 2009 related to management of hyperthyroidism in pregnancy. In this review, we discuss differential diagnosis of hyperthyroidism, management, importance of early diagnosis, and importance of achieving proper control to avoid maternal and fetal complications.ResultsDiagnosing hyperthyroidism during pregnancy can be challenging because many of the signs and symptoms are similar to normal physiologic changes that occur in pregnancy. Patients with Graves disease require prompt treatment with antithyroid drugs and should undergo frequent monitoring for signs of fetal and maternal hyperthyroidism and hypothyroidism. Rates of maternal and perinatal complications are directly related to control of hyperthyroidism in the mother. Thyroid receptor antibodies should be assessed in all women with hyperthyroidism to help predict and reduce the risk of fetal or neonatal hyperthyroidism or hypothyroidism. The maternal thyroxine level should be kept in the upper third of the reference range or just above normal, using the lowest possible antithyroid drug dosage. Hyperthyroidism may recurin the postpartum period as Graves disease or postpartum thyroiditis; thus, it is prudent to evaluate thyroid function 6 weeks after delivery. Preconception counseling, a multidisciplinary approach to care, and patient education regarding potential maternal and fetal complications that can occur with different types of treatment are important.ConclusionPreconception counseling and a multifaceted approach to care by the endocrinologist and the obstetric team are imperative for a successful pregnancy in women with Graves hyperthyroidism. (Endocr Pract. 2010;16:118-129)  相似文献   

19.
Summary

Invasion of the riparian zone by alien vegetation is recognised as a serious problem in many areas of South Africa. Vegetation is a dynamic component of river channels. It is an important control variable affecting channel form whereas the flow and sediment regime influences vegetation growth. Wherever alien vegetation invades the riparian zone it can be expected that there will be some impact on the physical structure of the riparian habitat. This paper reviews the effect of riparian vegetation on channel processes and channel form and discusses the implications of the invasion of riparian zones by alien vegetation. Woody species in particular are seen as having a significant potential for inducing channel modification, whilst their removal could lead to significant channel instability and mobilisation of sediment. The need for further research into the impact of alien vegetation on the geomorphology of South African river channels is stressed.  相似文献   

20.
BackgroundAnopheles stephensi was first recorded in the coastal area of Mannar District, Sri Lanka, in December 2016. Since then, this vector has been isolated from other districts in the Northern and Eastern Provinces of Sri Lanka. Chemical control is the main arm of vector control that can be used to reduce the vector densities within a short period. Thus, the present study aimed at evaluating the efficacy of using selected insecticides for the control of An. stephensi larvae.MethodThe third and fourth instar larval stages of An. stephensi (F2 generation) of field mosquitoes that were caught using cattle baited net trap collections from Columbuthurai, Kurunagar, and Navanthurai areas in Jaffna District, Sri Lanka, were obtained from the laboratory colony established at Jaffna. Batches of 100 larvae were taken for experiments and introduced separately to a concentration series of temephos and novaluron (0.04–400 ppm). A control test was also performed at each setup without introducing insecticides. The mortality rates of An. stephensi larvae exposed to different concentrations of larvicides were recorded at 1, 24 and 48-h intervals. The experiment was replicated five times at individual concentrations for each selected chemical. Data were analyzed using the General Linear Model (GLM) and Probit analysis.ResultsThe highest mortality rate (100%) at a 1-h exposure period was observed from temephos at >100 ppm. The mortality rates varied significantly for different concentrations and larvicides (p < 0.05). At 24-h of the exposure period, the 100% mortality of An. stephensi larvae were observed from both temephos and novaluron even at 0.04 ppm.ConclusionBoth temephos and novaluron reported 100% mortality rates in An. stephensi larvae at 1-h and 24-h exposure periods. Based on the findings, temephos and novaluron can be recommended as effective larvicides for chemical-based control of An. stephensi in Jaffna, Sri Lanka. Further, it is recommended to conduct a field-based study, where habitat types and water quality are highly heterogeneous and may affect the residual activity.  相似文献   

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