Genetic Diversity of the Black Mangrove Avicennia germinans (L.) Stearn in Northwestern Mexico

Olivia Millán-Aguilar,Richard Dodd,Alejandro Nettel-Hernanz,Ernesto Velázquez-Velázquez,Miguel Hurtado-Oliva,Marlenne Manzano-Sarabia

doi:10.3390/f7090197

Abstract

Mangrove forests of Mexico have been threatened by the effects of anthropogenic activities during the last decades, mostly related to aquaculture, agriculture, livestock and urban development. Genetic diversity and fine-scale genetic structure of two generations of the black mangrove Avicennia germinans (L.) Stearn were investigated in perturbed and preserved sites from three lagoon systems in Sinaloa, Mexico. Genetic diversity and overall genetic structure were similar between perturbed and preserved sites. However, lower levels of fine-scale spatial genetic structure were observed in two of the younger (sapling) generations. We attribute this to differences in local dynamics of each lagoon system, their status of conservation and levels of fragmentation. Also, low connectivity and the effects of disturbance could restrict the movement of pollinators and seed dispersal capabilities, resulting in low levels of genetic diversity and signs of inbreeding. Perturbed populations of A. germinans may play an important role in in situ conservation of this complex ecosystem.

Highlights

IntroductionAnthropogenic perturbation in tropical forests, e.g., mangroves, includes land conversion, habitat reduction and fragmentation, pollution, release of invasive species, human-induced fires, and direct exploitation [4,5]
Understanding the effects of anthropogenic perturbation on the genetic diversity of key forest species is crucial for the implementation of ecological conservation and management strategies [1,2,3].Anthropogenic perturbation in tropical forests, e.g., mangroves, includes land conversion, habitat reduction and fragmentation, pollution, release of invasive species, human-induced fires, and direct exploitation [4,5]
Results derived from STRUCTURE analysis of the three lagoon systems based on their age and status conservation, where (A) is represented by two genetics groups and status conservation, where (A) is represented by two genetics groups of adults; and (B) assignment of three genetics groups of saplings individuals

Summary

Introduction

Anthropogenic perturbation in tropical forests, e.g., mangroves, includes land conversion, habitat reduction and fragmentation, pollution, release of invasive species, human-induced fires, and direct exploitation [4,5]. Human-driven perturbations affect population demography that in turn could potentially lead to reductions in species genetic diversity and changes in patterns of genetic structure [7,8,9]. These disturbances could represent a real threat for the long term ability of species to respond if adaptive genetic traits are lacking [10]. Located in the transition zone between sea and land, these highly productive areas provide nurseries and refuges for several species, including those with economical importance [12]

Methods

Results

Conclusion