Naturalization of exotic plant species in north‐eastern North America: trends and detection capacity

Aim To reconstruct historical naturalization trends of exotic vascular plants in Quebec and Massachusetts, two regions that experienced fluctuations in their herbarium specimen collection efforts. We hypothesized that the observed trends are linked to the collection effort and that they differ according to the motive for plant introduction. Methods A checklist of naturalized exotic plant taxa for Quebec, including oldest proof of naturalization and motive for introduction, was built from herbaria, journals, dissertations, theses, bulletins, websites and unpublished records. For Massachusetts, we used the checklist of Sorrie (2005; Rhodora, 107 , 284–329). The collection effort was estimated from a pool of species with specimens from the five largest Quebec herbaria and from the Harvard University Herbarium. Results Naturalization trends of exotic plants in Quebec are similar to those observed in Massachusetts. A large part of the plants naturalized in the 17th, 18th or 19th centuries, with very little naturalization during the last 30–90 years. In general, there is a significant statistical link between herbarium specimen collection effort and the discovery of new naturalized plant taxa. Very few utilitarian plants naturalized in either region during the 20th century. In Quebec, a high number of ornamental plants naturalized during the last 100 years. Main conclusions The link between herbarium specimen collection effort and the discovery of new naturalized plants is real, although not as straightforward as it seems. Our analysis suggests that at least part of the decline in the number of new naturalized exotic plants observed in Quebec and Massachusetts during the last 30–90 years is a direct consequence of the low interest for traditional floristic studies. However, the possibility of a real decline cannot be ruled out. We nevertheless provide here one of the first pieces of evidence of the potential consequences of the decline of local plant collection for environmental management and especially for early detection systems of new invaders.     

First report of the exotic blue land planarian, Caenoplana coerulea (Platyhelminthes, Geoplanidae), on Menorca (Balearic Islands, Spain)

In April 2009 two specimens of a terrestrial flatworm were collected from under a rock in an orchard at Ciutadella de Menorca on the easternmost Balearic island of Menorca (Spain). Their external morphology suggested that both specimens belonged to the invasive blue planarian Caenoplana coerulea, a species which is native to eastern Australia. Sequence data of a fragment of the mitochondrial cytochrome c oxidase subunit I (COI) and of the entire 18S ribosomal RNA confirm its identification. This is one of the first records of the species in Europe where it has only been found in one locality in the United Kingdom, France and NE Spain.     

Translocation of the Eastern Bristlebird 2: applying principles to two case studies

Summary The Eastern Bristlebird (Dasyornis brachypterus) is an endangered endemic passerine of south‐eastern Australia. The re‐establishment of extirpated populations through translocation was identified as a key action in New South Wales to address the threats to this species associated with habitat fragmentation and widespread and frequent fire. At Jervis Bay during 2003–2005, 50 birds were translocated from Bherwerre Peninsula to Beecroft Peninsula. In the Illawarra in 2008, 50 birds were translocated from Barren Grounds Nature Reserve to Cataract. At Jervis Bay, monitoring indicated that after 7 years, (i) there was no detectable impact on the source population from the removal of birds and (ii) the count at Beecroft Peninsula was 94 birds, with dispersal up to 6.3 km from the release point. In the Illawarra, (i) the source population was recovering 3 years post‐removal and (ii) the maximum count at Cataract was 15 birds after 3.5 years, including evidence of breeding, and after 3 years, the maximum dispersal was 7 km from the release point. Both translocations adhered to five key principles as follows. (i) Feasibility analysis prior to each project was favourable. (ii) For 17 pre‐stated criteria for success, 14 and 10, respectively, were met for Jervis Bay and Illawarra. (iii) Financial accountability was achieved with detailed statements showing budgets of $201k and $92k, respectively, for Jervis Bay and Illawarra. (iv) Ecological research was incorporated into both projects. (v) The results of each project are progressively being published. The re‐introduction at Jervis Bay has succeeded, and we are optimistic about the Illawarra re‐introduction.     

宁夏国外小麦种质资源考察、引进和利用

国外小麦种质资源引进在宁夏小麦引种中发挥着重要的作用。碧玉麦、阿勃、墨卡(卡杰姆F-71)、WC-20(宁春37)、9186(宁冬6号)等国外小麦品种在宁夏生产上直接利用。宁夏春小麦的品质杂交选育始于1953年,利用国外小麦种质资源先后培育出斗地1号、宁春4号等50余个春麦品种。1990年宁夏国外冬麦种质资源的引进带动了宁夏引黄灌区冬麦北移和耕作改制的研究,也引发了宁夏冬麦品种杂交选育的研究。宁夏引黄灌区冬小麦品种的杂交选育的工作始于1991年,经过15年的努力,杂交选育出第一批冬麦品种宁冬10号、宁冬11号,2010年在冬麦生产上取代了明丰5088,不仅实现了宁夏引黄灌区冬小麦品种第3次更新、实现了小麦品种的5次更新,而且使宁夏小麦生产水平跃上新台阶,有力地促进宁夏引黄灌区耕作制度改善和种植业结构的调整。     

中国作物种质资源引进与流出研究

引进国外种质、促进粮食生产,对中国至关重要。中国每年从世界各地引进大量的作物遗传资源,如水稻、小麦、玉米、马铃薯、甘薯,当然主要是从国际农业研究磋商组织(CGIAR)各中心引进的。同时,中国也向国际农业研究磋商组织各中心和其他国家提供了许多作物遗传资源(如大豆),为世界做出了巨大贡献。种质资源的流动有利于中国,因此中国应该与国际农业研究磋商组织各中心和其他国家加强合作,组织专家系统研究并争取尽快加入《粮食和农业植物遗传资源国际条约》,强化统一管理,规范种质资源引进与输出,建立共享机制,推进种质资源共享。     

西南桦速生单株选择

采用方差分析、遗传参数分析和聚类分析方法,在福建省华安县引种实验林进行西南桦(Betula alnoides Buch.-Ham.ex D. Don)速生单株选择,从25个种源中筛选出8个优良种源,树高平均遗传增益为10.4%.对8个种源中69个家系进行聚类分析,选择出13个速生家系,树高的平均遗传增益为29.4%.运用K快速聚类法从95个单株中筛选出14株速生单株,其遗传增益为118.01%,增产效果显著,在闽南一带可用作无性繁殖材料,以加速西南桦引种造林良种化进程.     

论植物园的活植物收集

对植物园活植物收集评价、引种中的取样方法和迁地保护种群大小等问题进行了论述.对活植物收集的评价包括科学性和代表性,最具有科学意义的是经过调查从野外收集的有完整记录的材料,其次是从植物园等机构 引种的有记录的材料,再次是从各地引种的基本上无记录的材料.根据收集物的代表性可分为具有保护意义的收集和保护性收集.取样技术主要针对保护性收集而言,要求收集样本能涵盖该物种95%以上、频率大于5%的等位基因.活植物收集种群的大小应从科学性和现实性二方面来考虑,对植物园里大量的具有保护意义的收集,其种群大小为乔木10～20株,灌木40～50株,草本100～200株;对于保护性收集则至少为乔木50～100株,灌木200株或更多,草本300～500株以上.另外,对当前植物园活植物收集圃建设的一些重要问题也进行了探讨.     

In situ hatching of invertebrate diapausing eggs from ships' ballast sediment

Ships that enter the Great Lakes laden with cargo carry only residual ballast water and sediment in ballast tanks. These ships are designated ‘no ballast on board’ (NOBOB) and constitute > 90% of inbound traffic. We conducted in situ experiments using emergence traps to assess the viability and the introduction potential of invertebrate diapausing stages present in ships’ ballast sediment. All trials commenced while vessels operated on the lower lakes (Erie, Ontario) and were completed 6–11 days later at ports on the upper lakes (Michigan, Lake Superior). Eight trials were conducted on four ships using five different ballast sediments. Hatching was observed on every ship, although not from all sediments on all ships. Overall hatch rates were very low (0.5 individuals per 500 g sediment), typically involving activation of < 0.05% of total eggs present. Five species of rotifers and copepod nauplii were hatched from ballast sediments, although only one or two species typically hatched from any one sediment. Results of this study indicate that hatching of diapausing eggs contained in ballast sediment of NOBOB ships poses a relatively low risk of invasion to the Great Lakes. However, as reproduction may occur in tanks, and non‐indigenous species may be involved in numerous introduction events, the risk posed by this vector is small but potentially important. While dormancy is a characteristic enabling enhanced survival during transportation in ballast tanks, it becomes a hindrance for introduction.