Phenological responses of ash (Fraxinus excelsior) and sycamore (Acer pseudoplatanus) to riparian thermal conditions

There is increasing evidence that riparian corridors have modified thermal conditions compared to non-riparian areas. However, the biological significance of this difference is less clear. Here we tested this by investigating the response of tree phenology to riparian thermal conditions. We monitored the timing of bud burst, leaf fall and growing season of riparian and non-riparian ash (Fraxinus excelsior L.) and sycamore (Acer pseudoplatanus L.) in the city of Sheffield over two years. We compared the phenologies between riparian and non-riparian trees and explored the relationship between tree phenologies and thermal environments. Tree phenologies varied between riparian and non-riparian areas and the effect was species specific. Bud burst and leaf fall were earlier in non-riparian than in riparian ash, but no location effects on either bud burst or leaf fall were detected for sycamore, or in the growing season for both species. Bud burst for the two species was highly correlated to spring temperature; warmer temperature resulting in earlier bud burst in ash but later bud burst in sycamore. No significant relationship between leaf fall and temperature was found for either species. A positive correlation between growing season and temperature was observed for ash but not sycamore.     

我国农业网站运营中的问题及其对策

农业网站是加快农业信息传递和传播的重要载体,针对当前我国农业网站发展的基本现状,分析了农业网站发展中服务定位不清晰、运营效率不高、盈利模式不明确等发展＂瓶颈＂问题,指出农业网站的发展壮大需要通过从明晰网站定位、分离网站所有权与经营权和创新网站盈利模式上来解决,对农业网站形成合理的运营机制,更好地服务＂三农＂,具有重要的借鉴和指导意义。     

干旱半干旱石质山地困难立地植被恢复技术

近些年，我国的造林绿化事业以前所未有的速度发展，一些较易造林地区已基本上完成了造林任务。森林覆盖率大幅度提高．生态环境明显改善。因此，干旱半干旱石质山地困难立地的植被恢复问胚就成了今后林业工作的主要任务之一。但是石质山地由于生境恶劣及各种原因的破坏，历来造林困难很大，造林成活率、保存率不高。一些林分生长缓慢，稳定性差，林分质量低，不能发挥出较高的效益。通过应用和推广多年在石质山地植被恢复中已有的研究成果，进行现有技术的优化整合和组装配套，以提高造林成活率和保存率、提高林分和群落质量、加速植被恢复建设，是改善我国干旱半干旱石质山地困难立地植被恢复的重要举措。     

The sacred commons: Conflicts and solutions of resource management in sacred natural sites

Sacred natural sites are considered an additional pillar for biodiversity conservation, next to the protected areas network. However, sacred landscapes are not primarily conservation areas, but exist for cultural and social reasons. To evaluate their strengths and weaknesses as community-based conservation areas, a thorough understanding of the underlying values, institutional arrangements, and outcomes is required. Here, I use institutional economics for a meta-analysis of publications on sacred natural sites to identify potential conflicts in their maintenance, and to analyze institutional arrangements to solve these conflicts. I show that most sacred natural sites resemble common-pool resources and that many design principles that are linked to common-pool resources are also found in traditional institutions managing sacred places. Design principles are no blue-print solution but they may guide future research to identify locally robust institutional arrangements that are linked to the ecological integrity of sacred natural sites.     

Beef with environmental and quality attributes: Preferences of environmental group and general population consumers in Saskatchewan, Canada

We attempt to quantify and qualify the preferences of consumers for beef with a number of environmental and food quality attributes. Our goal is to evaluate the viability of a proposed food co-operative based in the Wood River watershed of southern Saskatchewan, Canada. The food co-operative was designed to provide a price premium to producers who adopted alternative management practices. In addition, the study evaluated the acceptance of a proposed food co-operative by consumer that had environmental interests as compared to the general population. Conjoint analysis was used to determine the trade-off and relative value of beef with the following production and purchasing characteristics: (a) use of hormones, antibiotics and vaccination in production; (b) method of obtaining the beef including monthly or yearly purchase contracts or a local market; (c) price relative to beef purchased from the local grocery store; and (d) impact on the river ecosystem. Consumers from environmental groups had stronger environmental and food quality preferences than individuals from the general population. However, consumers from both groups expressed a willingness to pay higher prices for food that had these attributes. It was uncertain whether the magnitude of the premium, in combination with a desire not to enter a long-term purchasing commitment, would be large enough to encourage farmers to adopt the alternative management. Ken W. Belcher is an Associate Professor in the Department of Agricultural Economics at the University of Saskatchewan. His research has focused on ecological economics and environmental policy with a particular interest in environmental conservation in agricultural landscapes. Andrea E. Germann was a Research Assistant with the Centre for Studies in Agriculture, Law and the Environment at the University of Saskatchewan. Josef K. Schmutz is a Research Fellow with the Centre for Studies in Agriculture, Law and the Environment. Joe has expanded his research interest on prairie raptors by fostering strategic design for alternative, local economies that include the conservation of birds and their ecosystems.     

A survey of antipredator controls at marine salmon farms in Scotland

A questionnaire survey was sent to managers of marine salmon farm sites in Scotland to update knowledge on problems from predators and the use of antipredator controls. Of the 195 respondents, 5 had no antipredator controls with the remaining 190 having some level of control. Throughout Scotland, managers reported 12 species of predator. Seals were reported to be predators at 81% of sites. In total, 19 different types of antipredator control were used. Top nets were employed most widely, being used by 88% of the 195 respondents followed by seal scarers (52%) and shooting (49%). Shooting was considered to be very effective by 45 (62%) of the 73 site managers who expressed an opinion on its effectiveness. Views on the effectiveness of seal scarers varied markedly among site managers, and only 21 (23%) of 92 managers considered them to be very effective. There was also considerable variation in the perceived effectiveness of different types of antipredator nets. Comparison with previous studies showed that although there was a significant increase in the proportion of farms at which seals were reported to have caused loss or damage between 1985 and 1987, there has been no further increase. There were no significant changes over time in reported problems from other species of predator. The proportions of farms using nets and shooting to deter predators are remarkably consistent between the study periods. However, the use of seal scarers has increased significantly from 10% in 1985 to 52% in 2001. The survey suggests that the degrees of protection afforded by predator control methods vary appreciably between sites. There is a need for a range of antipredator devices to be tested under controlled conditions to determine under which circumstances each is most effective. This is particularly the case regarding seal scarers.     

淮南市国控环境空气监测点位设置技术研究

对设置环境空气监测点位的目的及意义、设置依据、设置原则及环境功能区划进行了论述,明确了具体点位设置,为淮南市环境安全监测工作的展开提供参考。     

Effects of even-aged timber harvest on stream salamanders: Support for the evacuation hypothesis

Habitats worldwide are increasingly threatened by degradation and conversion. Critical to the process of habitat loss is the organismal response, which can have effects on immediate conservation measures or future restoration. Among the most threatened and underappreciated habitats are headwater streams, which are small but abundant features of montane forests. These habitats comprise a significant proportion of the total stream length, can harbor remarkable biodiversity, and are critical for numerous ecosystem processes. One of the most abundant organisms in montane headwater ecosystems are salamanders, and therefore what happens to salamanders when the forest habitats surrounding headwater streams are altered? Three main hypotheses exist: (1) mortality hypothesis; (2) retreat hypothesis; and (3) evacuation hypothesis. To examine these hypotheses we evaluated the impacts of even-aged riparian timber harvest on stream-breeding salamanders. Riparian forests along headwater streams were logged, leaving riparian buffers of 0 m, 9 m, and 30 m. Responses to each riparian alteration were measured in terms of salamander terrestrial habitat use and growth in the riparian habitat, as well as changes in population density within headwater streams. Adult and juvenile salamander densities measured in headwater streams were significantly greater in logged riparian treatments than in unaltered riparian treatments. In addition, salamanders significantly reduced their terrestrial habitat use following riparian logging with both the average distance from the stream and the relative abundance of salamanders decreasing. It is unlikely that salamanders will persist in highly modified riparian habitats, as we measured significantly reduced body conditions over short periods of time at these sites. We present corroborative evidence that salamanders evacuate the riparian habitat following intensive riparian logging, emigrating to adjacent headwater streams. Our results underscore the sensitivity of stream salamanders to riparian habitat alteration as well as the importance of riparian buffers in preserving amphibian assemblages.     

油茶芽苗砧嫁接育苗试验初报

以普通油茶作苗砧和接穗,进行芽苗砧嫁接试验,研究穗条不同部位芽对嫁接成活率及苗高生长的影响。结果表明：芽的部位对嫁接成活率影响差异显著,成活率顶芽〉中部芽〉下部芽;芽的部位对嫁接苗当年苗高的影响差异极为显著,顶芽苗高〉下部芽苗高,而顶芽与中部芽、中部芽与下部芽的苗高差异不显著。