Mixed Mating in Banksia brownii Baxter ex R. Br. (Proteaceae)

1994 ◽  
Vol 42 (1) ◽  
pp. 103 ◽  
Author(s):  
JF Sampson ◽  
BG Collins ◽  
DJ Coates
Keyword(s):  
Endangered Species ◽  
Minimum Variance ◽  
Outcrossing Rate ◽  
Mixed Mating ◽  
System Parameters ◽  
Rare And Endangered Species ◽  
Large Populations ◽  
Rare And Endangered ◽  
High Level ◽  
Two Populations

Mating system parameters of the rare and endangered species Banksia brownii were estimated for two populations using both the mixed mating and effective selfing models. Estimates of outcrossing rate were similar in both populations for both models (mixed mating t Pop. 1=0.68, Pop. 2=0.75; effective selfing t Pop. 1=0.65, Pop. 2=0.73) and were among the lowest reported for undisturbed Banksia populations. Banksia brownii is killed by fire and the high level of selfing found may be associated with this trait. Multilocus and minimum variance mean i estimates were similar and the covariance of selfing with gene fixation (D) was not significantly different from zero indicating that populations were not structured and that most of the inbreeding was the result of self-fertilisation. The absence of structure was attributed to gene dispersal through pollen disperse by birds, and selection against inbred seed. It is suggested that several entire, large populations of this species together with habitat sufficient to support pollinators be reserved to conserve this species.

scholarly journals Paternal bottlenecks in fragmented populations of the grassland daisy Rutidosis leptorrhynchoides

1999 ◽  
Vol 73 (2) ◽  
pp. 111-117 ◽  
Author(s):  
ANDREW G. YOUNG ◽  
ANTHONY H. D. BROWN
Keyword(s):  
Mating System ◽  
Inbreeding Depression ◽  
Outcrossing Rate ◽  
Small Populations ◽  
Isolated Populations ◽  
Fragmented Populations ◽  
System Parameters ◽  
Large Populations ◽  
Spatial Isolation ◽  
High Level

Allozyme markers were used to estimate mating system parameters in nine fragmented populations of the grassland daisy Rutidosis leptorrhynchoides that differed in size and spatial isolation. Multilocus estimates of outcrossing rate did not differ significantly among populations, all indicating a high level of outcrossing (tm=0·84–1·0). Small populations showed greater divergence than large populations between the allele frequencies in the population and those in the pollen pool, indicating paternal bottlenecks. Isolated populations of fewer than 200 individuals also exhibited higher correlations of outcrossed paternity (rp) than larger populations, indicating the production of more full-sibs within families. The combination of paternal bottlenecks and correlated paternity increases the genetic identity of progeny across families and predisposes populations to biparental inbreeding in subsequent generations. As over half the remaining populations of R. leptorrhynchoides contain fewer than 200 plants, such second-order inbreeding may threaten the viability of the species if it is associated with significant inbreeding depression.

Genetic diversity and genetic structure of the rare and endangered species, Primula ranunculoides

2014 ◽  
Vol 21 (5) ◽  
pp. 601-609
Author(s):  
Wang Deyun ◽  
Peng Jie ◽  
Chen Yajing ◽  
Lü Guosheng ◽  
Zhang Xiaoping ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Endangered Species ◽  
Rare And Endangered Species ◽  
Rare And Endangered

Geoecological analysis of the Russian Federation regions representation in the state program “Environmental Protection”

2020 ◽  
Vol 957 (3) ◽  
pp. 47-53
Author(s):  
E.A. Kravets
Keyword(s):  
Endangered Species ◽  
Environmental Protection ◽  
Russian Federation ◽  
The State ◽  
Volga River ◽  
Unequal Distribution ◽  
State Program ◽  
Rare And Endangered Species ◽  
Rare And Endangered ◽  
The Russian Federation

The author offers mapping and geoecological analysis of the Russian Federation regions presence in the state program “Environmental Protection”. The unequal distribution of the program’s targets and activities in different regions is revealed. A considerable number of relevant environmental problems for several mentioned regions have not been reflected in the program. It is important to increase the area of specially protected natural areas for a significant number of subjects of the Russian Federation. The status “part of the territory occupied by specially protected natural territories of Federal value in the total area of the subject of the Russian Federation” is recommended to be assigned all regions of Russia. Identification and elimination of objects of accumulated environmental damage that threat to the Volga river is relevant, at least for all the regions in which the Volga flows. Not all regions with a high level of air pollution and/or large masses of air pollutants have the indicator “reduction of total emissions for the reporting year”. It is necessary to increase the Program of measures for the protection of rare and endangered species of plants and to expand the list of regions in which it is planned to protect rare and endangered species of animals.

scholarly journals Research on a Biodiversity Conservation Value Assessment Method Based on Habitat Suitability of Species: A Case Study in Gansu Province, China

2021 ◽  
Vol 13 (6) ◽  
pp. 3007
Author(s):  
Xiaojiong Zhao ◽  
Jian Wang ◽  
Junde Su ◽  
Wei Sun ◽  
Haoxian Meng
Keyword(s):  
Ecosystem Services ◽  
Endangered Species ◽  
Biodiversity Conservation ◽  
Gansu Province ◽  
Distribution Area ◽  
Suitable Habitat ◽  
Conservation Value ◽  
Value Assessment ◽  
Rare And Endangered Species ◽  
Rare And Endangered

Quantitative assessment and evaluation of ecological parameters and biodiversity conservation are prime concerns for long-term conservation of rare and endangered species and their associated habitats in any ecological region. In this study, Gansu Province, a biodiversity hotspot, was chosen as the research area. We predicted the distribution patterns of suitable habitats for rare and endangered species. The replacement cost method was adopted to calculate the conservation value of rare and endangered species. The suitable habitat distribution area of rare and endangered wild animals reached 351,607.76 km2 (without overlapping area), while that of plants reached 72,988.12 km2 (without overlapping area). The conservation value of rare and endangered wildlife is US $1670.00 million. The high-value areas are mostly concentrated in the south and north of Gansu Province. The conservation value of rare and endangered wild plants is US $56,920.00 million. The high-value areas are mostly concentrated south of Gansu Province. The conservation value is US $58,590.00 million a year, and its distribution trend is gradually decreasing from northeast to southwest, with the highest in the forest area south of Gansu Province, followed by the Qilian Mountain area in the north. These results are of great significance for future improvement of the evaluation index system of ecosystem services and the development of ecosystem services and management strategies.

scholarly journals [First occurrence of Sea Lamprey, Petromyzon marinus Linnaeus 1758 (Agnatha, Petromyzontiformes, Petromyzontidae) in the River Mignone (Northern Lazio).]

2021 ◽  
Vol 8 (1) ◽  
pp. 29-34
Author(s):  
Vincenzo Ferri ◽  
Paolo Crescia ◽  
Christiana Soccini ◽  
Alessio Olini ◽  
Stefano Celletti
Keyword(s):  
Endangered Species ◽  
Petromyzon Marinus ◽  
Sea Lamprey ◽  
Environmental Context ◽  
Upstream Migration ◽  
Rare And Endangered Species ◽  
Fish Ladder ◽  
First Occurrence ◽  
Rare And Endangered

[The spring presence of two individuals of the Sea lamprey, Petromyzon marinus, in the River Mignone near Tarquinia (Northern Lazio) could highlight a new Italian reproductive site of this rare and endangered species. This exceptional possibility could certainly be favored by the good quality of both the waters of the Mignone, and the environmental context of the record, but would require the urgent equipment of the barrier of Le Mole with a fish ladder in order to allow the sea lamprey’s upstream migration towards the areas of the upper course, even more suitable for their reproduction].   [Article in Italian]

The USSR programme for breeding amphibians, including rare and endangered species

2007 ◽  
Vol 28 (1) ◽  
pp. 10-21 ◽  
Author(s):  
B. F. GONCHAROV ◽  
O. I. SHUBRAVY ◽  
I. A. SERBINOVA ◽  
V. K. UTESHEV
Keyword(s):  
Endangered Species ◽  
Rare And Endangered Species ◽  
Rare And Endangered
Sign in / Sign up

Export Citation Format

Share Document