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91.
Conservation of the Toromiro Tree: Case Study in the Management of a Plant Extinct in the Wild 总被引:1,自引:0,他引:1
Mike Maunder Alastair Culham † Bjorn Alden ‡ Georg Zizka § Cathérine Orliac Wolfram Lobin †† Alberto Bordeu ‡‡ Jose M. Ramirez §§ and Sabine Glissmann-Gough 《Conservation biology》2000,14(5):1341-1350
Abstract: We reviewed the history and conservation of Sophora toromiro , a species that has been extinct in the wild since 1960 but has survived as scattered individuals in botanic gardens and private collections. The short-term conservation of S. toromiro is dependent on the management of surviving ex situ stocks. This is being achieved through international collaboration by a working group established to coordinate the conservation management of the species. Molecular evidence indicates that the species retains greater genetic variability than expected. The greatest amount of genetic variability was located in specimens outside botanic garden collections. No unmodified natural habitat survives on Rapa Nui ( Easter Island); so opportunities to establish a viable wild population are limited. Evidence from past reintroductions indicates that the best short-term opportunity for the species is through conventional horticultural management in botanic gardens and traditional farm plots on Rapa Nui. Some extinct-in-the-wild taxa (sensu World Conservation Union 1994), such as the Toromiro, retain genetic variability, and appropriate reintroduction sites exist. These taxa represent valid priorities for conservation management. 相似文献
92.
Ana Cristina Mugetti Alberto Tomás Calcagno Carlos Alberto Brieva María Silvia Glangiobbe Andrea Pagani Silvia G.Gonzalez 《Ambio-人类环境杂志》2004,33(1):67-75
本文描述了南美大陆南部陆地和东南沿海地区环境特性及水生栖息地和群落的现状(GIWA巴塔哥尼亚大陆架亚区),结果来自一项GIWA项目框架任务所完成的一份全面评估,绝大部分依据的是公开发表的数据.分析主要集中在跨边界水资源目前的情况和人类活动带来的影响.内陆水体的栖息地和群落变化主要是由为发电和其他用途而建的水坝和水库引起的.从活水环境到净水环境影响了生境,造成了生物群落的改变.在拉普拉塔(La Plata)河流域,外来入侵物种使本地物种消失.过度捕捞和污染影响了生物多样性,造成了海洋栖息地质量下降.本篇文章讨论了相关的原因,讨论了布宜诺斯艾利斯省和渔业资源由两国共享的阿根廷-乌拉圭公共渔业区对沿海生态环境的政策选择. 相似文献
93.
94.
Alberto Maturana Palacios 《生态毒理学报》1998,20(3):19-21
智利的经验显示,APELL原则可以与当地应急规划举措相结合.APELL对工业事故的非排他性和不是唯一答案"思路也可以应用于其它类型的紧急状况,包括自然灾害(或自然灾害与工业灾害的组合).因此,APELL特别适合应用于港口.这种APELL思路促进了潜在受影响社区的参与--关于港口的另一个重要考虑. 相似文献
95.
Alberto Addis Francesca Biagi Antonello Floris Emiliana Puddu Marcella Carcupino 《Marine Biology》2007,152(3):733-744
The larval development of the newly discovered cephalocarid from Mediterranean sea, Lightiella magdalenina, was analysed using light and scanning electron microscopy. Twenty-nine larval specimens, divided into 15 metanaupliar and
2 juvenile stages of development, were found. The first six metanaupliar stages had an even number (6, 8, 10, 12, 14 and 16)
of trunk segments including telson. The condition of 20 trunk segments, typical of the adult, was reached after another 4
stages by the addition of a single segment per stage. At this tenth stage, the larvae had an incomplete number of trunk limbs.
Another five stages were needed to complete the cephalic appendage development, passing from the metanaupliar to the juvenile
stage, characterized by loss of the naupliar enditic process of the second antenna. Trunk limbs development was completed
during the last two juvenile stages. According to the ontogenetic data reported for Hutchinsoniella macracantha and Lightiella incisa, these seventeen stages probably do not represent the complete developmental series. Nevertheless, they allow us to clarify
the main features of cephalocarid ontogeny and show specific differences in the development of both the trunk segments and
appendages. 相似文献
96.
Mendoza A Garcia MR Vela P Lozano DF Allen D 《Journal of the Air & Waste Management Association (1995)》2005,55(12):1797-1808
An inventory of air pollutants emitted from forest and agricultural fires in Northeastern Mexico for the period of January to August of 2000 is presented. The emissions estimates were calculated using an emissions factor methodology. The inventory accounts for the emission of carbon monoxide (CO), methane, nonmethane hydrocarbons, ammonia, nitrogen oxides, and particulate matter (PM). Particulate matter emissions include estimates for fine PM and coarse PM. A total of 2479 wildfires were identified in the domain for the period of interest, which represented approximately 810,000 acres burned and 621,130 short tons emitted (81% being CO). The main source of information used to locate and estimate the extent of the fires came from satellite imagery. A geographic information system was used to determine the type of vegetation burned by each fire. More than 54% of the total area burned during the period of study was land on the State of Tamaulipas. However, >58% of the estimated emissions came from the State of Coahuila. This was because of the mix of vegetation types burned in each state. With respect to the temporal distribution, 76.9% of the fires occurred during the months of April and May consuming almost 78% of the total area burned during the period of study. Analysis of wind forward trajectories of air masses passing through the burned areas and 850-mb wind reanalyses indicate possible transboundary transport of the emissions from Mexico to the United States during the occurrence of the major wildfires identified. 相似文献
97.
Pereira JL da Silva AA Picanço MC de Barros EC Jakelaitis A 《Journal of environmental science and health. Part. B》2005,40(1):45-54
The aim of this study was to evaluate the impact of the herbicide mixture nicosulfuron + atrazine, with or without the insecticide chlorpyrifos, onto soil entomofauna under maize crop. The treatments, applied 25 days after maize emergence, were represented by a weeded control without insecticide and herbicide, a weeded control with chlorpyrifos, and mixtures of nicosulfuron + atrazine, with or without chlorpyrifos. Arthropods populations, on the soil surface, as well as inside the soil under maize, were principally represented by mites (Arachnida: Acari), decomposer collembolans (Hexapoda:Parainsecta:Collembola) and predator ants (Hymenoptera:Formicidae). The nicosulfuron + atrazine mixture with chlorpyrifos and the isolated chlorpyrifos reduced the population dynamics of all insect groups on the soil surface compared to the weeded control. In the soil, mite and ant populations were reduced after application of the herbicide mixture with chlorpyrifos and of the isolated chlorpyrifos. 相似文献
98.
Báez AP Torres Mdel C García RM Padilla HG 《Environmental science and pollution research international》2002,9(4):230-233
A great number of studies on the ambient levels of formaldehyde and other carbonyls in the urban rural and maritime atmospheres have been published because of their chemical and toxicological characteristics, and adverse health effects. Due to their toxicological effects, it was considered necessary to measure these compounds at different sites in the metropolitan area of Mexico City, and to calculate the total rate of photolytic constants and the photolytic lifetime of formaldehyde and acetaldehyde. Four sites were chosen. Sampling was carried out at different seasons and atmospheric conditions. The results indicated that formaldehyde was the most abundant carbonyl, followed by acetone and acetaldehyde. Data sets obtained from the 4 sites were chosen to calculate the total rate of photolysis and the photolytic lifetime for formaldehyde and acetaldehyde. Maximum photolytic rate values were obtained at the maximum actinic fluxes, as was to be expected. 相似文献
99.
Alberto Velando Roxana Torres Irene Espinosa 《Behavioral ecology and sociobiology》2005,58(2):175-180
Sexual selection models suggest that female choice is based on male traits that indicate their genetic or environmental condition, consequently enhancing her reproductive success by direct or indirect benefits. We investigated the relationship between male foot colour and offspring condition in the blue-footed booby, a socially monogamous seabird, with conspicuous and variably condition-dependent coloured feet that are selected by females. In a cross-fostering experiment, we found that chick condition was related to the foot colour of the foster father and, to some extent, to the foot colour of the genetic father; thus overall, the fathers sexual ornamentation (genetic and foster) explained 32% of variance of chick condition. These data suggest that foot colour, a dynamic sexually selected trait, is mostly a signal of parental contribution. In species in which males provide parental care, females may choose mates with higher parental ability. Overall, our data suggest that colourful integuments are honest signals of parental ability.Communicated by J. Graves 相似文献
100.
Female preference for dominant males is widespread and it is generally assumed that success in male-male competition reflects high quality. However, male dominance is not always attractive to females. Alternatively, relatively symmetric individuals may experience fitness advantages, but it remains to be determined whether males with more symmetrical secondary sexual traits experience advantages in both intra- and intersexual selection. We analysed the factors that determine dominance status in males of the lizard Lacerta monticola, and their relationship to female mate preference, estimated by the attractiveness of males' scents to females. Sexually dimorphic traits of this lizard (head size and femoral pores) appear to be advanced by different selection pressures. Males with relatively higher heads, which give them advantage in intrasexual contests, were more dominant. However, head size was unimportant to females, which preferred to be in areas marked by relatively heavier males, but also by males more symmetric in their counts of left and right femoral pores. Chemicals arising from the femoral pores and other glands might honestly indicate quality (i.e. related to the symmetry levels) of a male to females and may result from intersexual selection. Females may use this information because the only benefit of mate choice to female lizards may be genetic quality. Chemical signals may be more reliable and have a greater importance in sexual selection processes of lizards than has previously been considered. 相似文献