Understanding genetic diversity of relict forests. Linking long-term isolation legacies and current habitat fragmentation in Abies pinsapo Boiss

Fencing wildlife populations can aid wildlife management goals, but potential benefits may not always outweigh costs of confinement. Population isolation can erode genetic diversity and lead to the accumulation of inbreeding, reducing viability and limiting adaptive potential. We used microsatellite and mitochondrial DNA data collected from 640 white-tailed deer confined within a 1184 ha fence to quantify changes in genetic diversity and inbreeding over the first 12 years of confinement. Genetic diversity was sustained over the course of the study, remaining comparable to unconfined white-tailed deer populations. Uneroded genetic diversity suggests that genetic drift is mitigated by a low level of gene flow, which supports field observations that the fence is not completely impermeable. In year 9 of the study, we observed an unexpected influx of mtDNA diversity and drop in inbreeding as measured by FIS. A male harvest restriction imposed that year increased male survival, and more diverse mating may have contributed to the inbreeding reduction and temporary genetic diversity boost we observed. These data add to our understanding of the long-term impacts of fences on wildlife, but also highlight the importance of continued monitoring of confined populations.

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Soil microbial dynamics and genetic diversity in soil under monoculture wheat grown in different long-term management systems

Soil Biology and Biochemistry ◽

10.1016/j.soilbio.2006.12.016 ◽

2007 ◽

Vol 39 (6) ◽

pp. 1391-1400 ◽

Cited By ~ 35

Author(s):

Carmine Crecchio ◽

Maddalena Curci ◽

Antonella Pellegrino ◽

Patrizia Ricciuti ◽

Nunzia Tursi ◽

...

Keyword(s):

Genetic Diversity ◽

Management Systems ◽

Microbial Dynamics ◽

Soil Microbial ◽

Term Management

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Managing drought-sensitive forests under global change. Low competition enhances long-term growth and water uptake in Abies pinsapo

Forest Ecology and Management ◽

10.1016/j.foreco.2017.10.017 ◽

2017 ◽

Vol 406 ◽

pp. 72-82 ◽

Cited By ~ 15

Author(s):

Victor Lechuga ◽

Vinicio Carraro ◽

Benjamín Viñegla ◽

José Antonio Carreira ◽

Juan Carlos Linares

Keyword(s):

Global Change ◽

Water Uptake ◽

Abies Pinsapo

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Microsatellite-Based Genetic Structure and Hybrid Detection in Alpacas Bred in Poland

Animals ◽

10.3390/ani11082193 ◽

2021 ◽

Vol 11 (8) ◽

pp. 2193

Author(s):

Angelika Podbielska ◽

Katarzyna Piórkowska ◽

Tomasz Szmatoła

Keyword(s):

Genetic Diversity ◽

Microsatellite Markers ◽

First Generation ◽

Expected Heterozygosity ◽

Hybrid Detection ◽

Average Coefficient ◽

Mixed Origin ◽

Generation Hybrid

This study aimed to characterize the population structure and genetic diversity of alpacas maintained in Poland using 17 microsatellite markers recommended by the International Society for Animal Genetics. The classification of llamas, alpacas, and hybrids of both based on phenotype is often difficult due to long-term admixture. Our results showed that microsatellite markers can distinguish alpacas from llamas and provide information about the level of admixture of one species in another. Alpacas admixed with llamas constituted 8.8% of the tested individuals, with the first-generation hybrid displaying only 7.4% of llama admixture. The results showed that Poland hosts a high alpaca genetic diversity as a consequence of their mixed origin. More than 200 different alleles were identified and the average observed heterozygosity and expected heterozygosity values were 0.745 and 0.768, respectively, the average coefficient of inbreeding was 0.034, and the average polymorphism information content value was 0.741. The probability of exclusion for one parent was estimated at 0.99995 and for two parents at 0.99999.

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Low genetic diversity in the endangered Taxus yunnanensis following a population bottleneck, a low effective population size and increased inbreeding

Silvae Genetica ◽

10.1515/sg-2016-0008 ◽

2016 ◽

Vol 65 (1) ◽

pp. 59-66 ◽

Cited By ~ 3

Author(s):

Y. C. Miao ◽

Z. J. Zhang ◽

J. R. Su

Keyword(s):

Genetic Diversity ◽

Habitat Fragmentation ◽

Population Size ◽

Effective Population Size ◽

Spatial Genetic Structure ◽

Population Bottleneck ◽

Effective Population ◽

Taxus Yunnanensis ◽

Low Genetic Diversity ◽

Two Populations

Abstract Taxus yunnanensis, which is an endangered tree that is considered valuable because it contains the effective natural anticancer metabolite taxol and heteropolysaccharides, has long suffered from severe habitat fragmentation. In this study, the levels of genetic diversity in two populations of 136 individuals were analyzed based on eleven polymorphic microsatellite loci. Our results suggested that these two populations were characterized by low genetic diversity (NE = 2.303/2.557; HO = 0.168/0.142; HE = 0.453/0.517), a population bottleneck, a low effective population size (Ne = 7/9), a high level of inbreeding (FIS = 0.596/0.702), and a weak, but significant spatial genetic structure (Sp = 0.001, b = −0.001*). Habitat fragmentation, seed shadow overlap and limited seed and pollen dispersal and potential selfing may have contributed to the observed gene tic structure. The results of the present study will enable development of practical conservation measures to effectively conserve the valuable genetic resources of this endangered plant.

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Impacts of habitat fragmentation on genetic diversity in a tropical forest butterfly on Borneo

Journal of Tropical Ecology ◽

10.1017/s0266467407004543 ◽

2007 ◽

Vol 23 (6) ◽

pp. 623-634 ◽

Cited By ~ 21

Author(s):

Suzan Benedick ◽

Thomas A. White ◽

Jeremy B. Searle ◽

Keith C. Hamer ◽

Nazirah Mustaffa ◽

...

Keyword(s):

Genetic Diversity ◽

Time Delay ◽

Habitat Fragmentation ◽

Forest Fragmentation ◽

Haplotype Diversity ◽

Genetic Erosion ◽

Forest Sites ◽

Increased Risk ◽

Forest Remnants ◽

Mtdna Diversity

Many areas of rain forest now exist as habitat fragments, and understanding the impacts of fragmentation is important for determining the viability of populations within forest remnants. We investigated impacts of forest fragmentation on genetic diversity in the butterfly Mycalesis orseis (Satyrinae) in Sabah (Malaysian Borneo). We investigated mtDNA diversity in 90 individuals from ten forest sites typical of the sizes of forest remnants that currently exist in the region. Nucleotide diversity declined with increasing isolation of remnants, but there was no effect of remnant size or population size, and haplotype diversity was similar among sites. Thus, approximately 50 y after forest fragmentation, few changes in genetic diversity were apparent and remnants apparently supported genetically viable populations of this butterfly. Many studies have shown that responses of species to habitat fragmentation usually follow a time delay, and so we developed a Monte Carlo simulation model to investigate changes in genetic diversity over time in small remnants. Model output indicated a substantial time delay (> 100 y) between fragmentation and genetic erosion, suggesting that, in the smallest study remnants, an increased risk of extinction from reduced genetic diversity is likely in the longer term.

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Genetic Differentiation in Isolated Populations of Hakea carinata (Proteaceae)

Australian Journal of Botany ◽

10.1071/bt97123 ◽

1998 ◽

Vol 46 (6) ◽

pp. 671 ◽

Cited By ~ 4

Author(s):

G. J. Starr ◽

S. M. Carthew

Keyword(s):

Gene Flow ◽

Habitat Fragmentation ◽

Gene Diversity ◽

South Australia ◽

Similar Species ◽

Isolated Populations ◽

Plant Populations ◽

Evolutionary Condition ◽

Private Alleles

Fragmentation of the landscape by human activity has created small, isolated plant populations. Hakea carinata F. Muell. ex Meissner, a sclerophyllous shrub, is common in isolated fragments of vegetation in South Australia. This study investigated whether habitat fragmentation has caused restrictions to gene flow between populations. Gene diversity (HT = 0.317) is average for similar species but little is held within populations (HS = 0.168) and 46.9% of gene diversity is accounted for between populations. Estimates of gene flow are NM = 0.270 (based on FST) and NM = 0.129 (based on private alleles). Populations are substantially selfing (t = 0.111). Small isolated populations appears to be a long-term evolutionary condition in this species rather than a consequence of habitat fragmentation; however, population extinctions are occurring. Conservation will require the reservation of many populations to represent the genetic variation present in the species.

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Captive management and the maintenance of genetic diversity in a vulnerable marsupial, the greater bilby

Australian Mammalogy ◽

10.1071/am14009 ◽

2015 ◽

Vol 37 (2) ◽

pp. 170 ◽

Cited By ~ 6

Author(s):

Emily J. Miller ◽

Mark D. B. Eldridge ◽

Keith Morris ◽

Neil Thomas ◽

Catherine A. Herbert

Keyword(s):

Genetic Diversity ◽

Captive Breeding ◽

Natural Habitat ◽

Species Conservation ◽

Molecular Data ◽

Breeding Programs ◽

Captive Populations ◽

Genetic Impact ◽

Captive Breeding Programs

The endemic Australian greater bilby (Macrotis lagotis) is a vulnerable and iconic species. It has declined significantly due to habitat loss, as well as competition and predation from introduced species. Conservation measures include a National Recovery Plan that incorporates several captive breeding programs. Two of these programs were established within 12 months of one another (1997/98), with the same number and sex ratio of founding individuals, but executed different breeding strategies: (1) unmanipulated mating in semi–free range natural habitat versus (2) minimising mean kinship in large enclosures, with the supplementation of new individuals into both populations. This study evaluates the long-term genetic impact of these programs and examines the congruency between the pedigree studbook estimates of diversity and molecular data. Our data demonstrate that genetic diversity was maintained in both populations, with the supplementation of new individuals contributing to the gene pool. The studbook estimates of diversity and inbreeding are not consistent with the microsatellite data and should not solely be relied upon to evaluate the genetic health of captive populations. Our analyses suggest that captive breeding programs may not require costly and intensive management to effectively maintain long-term genetic diversity in a promiscuous species.

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No Evidence of Low Genetic Diversity Despite High Levels of Inbreeding and Poor Genetic Connectivity Among Tetrastigma loheri (Vitaceae) Populations in Remaining Forest Areas in Cebu, Philippines

Systematic Botany ◽

10.1600/036364421x16370109698614 ◽

2021 ◽

Vol 46 (4) ◽

pp. 951-961

Author(s):

Jasper John A. Obico ◽

Hemres Alburo ◽

Julie F. Barcelona ◽

Marie Hale ◽

Lisa Paguntalan ◽

...

Keyword(s):

Genetic Diversity ◽

Habitat Fragmentation ◽

Tropical Forests ◽

Forest Cover ◽

Genetic Connectivity ◽

Philippine Island ◽

Low Genetic Diversity ◽

History Of ◽

Gap Data ◽

The Impact

Abstract— Little is known about the effects of habitat fragmentation on the patterns of genetic diversity and genetic connectivity of species in the remaining tropical forests of Southeast Asia. This is particularly evident in Cebu, a Philippine island that has a long history of deforestation and has lost nearly all of its forest cover. To begin filling this gap, data from 13 microsatellite loci developed for Tetrastigma loheri (Vitaceae), a common vine species in Philippine forests, were used to study patterns of genetic diversity and genetic connectivity for the four largest of the remaining forest areas in Cebu. Evidence of relatively high levels of inbreeding was found in all four areas, despite no evidence of low genetic diversity. The four areas are genetically differentiated, suggesting low genetic connectivity. The presence of inbreeding and low genetic connectivity in a commonly encountered species such as T. loheri in Cebu suggests that the impact of habitat fragmentation is likely greater on rare plant species with more restricted distributions in Cebu. Conservation recommendations for the remaining forest areas in Cebu include the establishment of steppingstone corridors between nearby areas to improve the movement of pollinators and seed dispersers among them.

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