首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到4条相似文献,搜索用时 0 毫秒
1.
Summary Ecotypes of Galium spurium L. var. echinospermon with distinct germination phenologies were found to occur in two adjacent plots of a grassland nature reserve with different management histories: a spring-germinating population is present in a winter-burnt plot, and an autumn-germinating type in an unburnt plot. These ecotypes share common flowering and fruiting phenologies, and disperse their seeds in early summer. Markedly contrasting thermal dormancy/germination characteristics were demonstrated for their seeds in systematic laboratory tests performed after several types of seed storage including storage in the field. The primary dormancy of seeds of the spring germinator was removed by moist-chilling or field winter-chilling, while that of the autumn germinator was removed by moist storage at 25°C or field summer temperatures. Biseasonal seedling emergence of the species appears to be due to a local differentiation of distinct ecotypes.  相似文献   

2.
3.
Over the past decade, there has been a concerted effort to better understand the distribution and abundance of reptiles in agricultural landscapes and to specifically evaluate their response to revegetation (tree and shrub plantings) and habitat restoration in the wheat‐sheep belt of south‐eastern Australia. This article reviews the response of reptiles to revegetation and woodland management and provides ten insights and lessons that can be applied to help improve reptile conservation in temperate eucalypt woodlands and fragmented agricultural landscapes in Australia. The review focuses primarily on revegetation programmes conducted by Landcare and Greening Australia, and management interventions funded by Local Land Services in NSW and Catchment Management Authorities in Victoria.  相似文献   

4.
Abstract. The upper courses of brook valley systems harbour Nardo‐Galion saxatilis communities characteristic of oligo‐trophic soils under low‐intensity farming. Most of these communities have disappeared under intensified farming i.e. application of fertilizers. We studied the possibilities of restoration i.e. re‐establishment of the former plant community by adopting various cutting regimes after the cessation of fertilization in 1972. The various cutting regimes revealed different effects after 25 yr. Regimes with cutting every second year with or without removal of the swath, and complete abandonment deviated from the other regimes that included annual haymaking with different frequency and timing. The latter group of cutting regimes came closer to the community of an adjacent field where fertilization stopped in 1967. This field in turn harboured several Nardo‐Galion species after 25 yr of annual cutting, and showed more resemblance with a local reference community (at a distance of 500 m) that had not been fertilized since the 1940s. The local reference still does not match poorly developed Nardo‐Galion saxatilis communities found in the region of ca. 50 km around the study area, and is far from well developed Nardo‐Galion communities in the same region. The study site still harbours several species characteristic of eutrophic soil and few species characteristic of oligotrophic soil after 25 yr of annual cutting and removal of the swath. The soil seed bank harbours only few target species. Although species characteristic of oligotrophic soil are present in an adjacent field and Nardo‐Galion saxatilis species occur at 500 m, they have not (yet) established in the target area.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号