Delineation of seed collection zones based on environmental and genetic characteristics for Quercus suber L. in Sardinia, Italy

Abstract

The assessment of seed zones or regions of provenance (RoP) to preserve local adaptation of tree species is an effective tool for the correct management of forest reproductive materials. The RoP for a species or sub-species is the area or group of areas subject to sufficiently uniform ecological conditions in which stands or seed sources show similar phenotypic or genetic characters, taking into account altitudinal boundaries where appropriate. However, the delineation of RoPs is commonly based on estimates of intrinsic environmental homogeneity, mainly climate and/or soil characteristics. The integration of genetic data into RoP maps is an important strategy to obtain a sound tool for managing forest reproductive materials. A study on Quercus suber (cork oak) in Sardinia (Italy) was carried out with the aim of determining ecological regions of provenance, investigating the genetic diversity among populations at the regional scale and identifying possible areas of interest for valorising the available germplasm. Identification of these areas was performed by Reserve Selection Analysis, which allows to identify priority areas by assessing the minimum number of sites required to include all the genetic diversity estimated by genetic analysis. Four spatial clusters were obtained based on environmental data: the northern and northern-eastern parts of the island were included in the Northern RoP; the second RoP covered the western part; and the third RoP enclosed the south-eastern region. The last group was distributed on the central part of the island (Central RoP) and includes the higher elevations. The sampled populations showed a low differentiation among populations and low diversity. According to the Reserve Selection Analysis, four conservation priority areas were identified. These indications can be useful at the local level because these sites can be proposed as stands for seed collection for future plantations.

Evaluating WorldClim Version 1 (1961–1990) as the Baseline for Sustainable Use of Forest and Environmental Resources in a Changing Climate

“…Derived surfaces are fundamental in order to plan future management strategies. For instance, and concerning forestry, additional strata, such as homogeneous climate zones, are needed as a fundamental tool to plan the transfer of genetic resources and reproductive materials across specific geographic areas [74,75]. WorldClim grids were interpolated with spline functions, a fast method known to yield results similar to polynomial functions but without mathematical instability.…”

Exploring Nonlinear Intra-Annual Growth Dynamics in Fagus sylvatica L. Trees at the Italian ICP-Forests Level II Network

“…The full list of the 36 variables is reported in Table 4 where each variable was calculated according to Wang et al [52]. Such variables have often been used in ecological modelling, with the aim to characterize the ecological niche of forest tree species as well as to apply climate change scenarios [53][54][55][56] and demonstrated suitability for predicting local climate conditions. Even if directly available from the ClimateEU software (https://sites.ualberta.ca/~{}ahamann/data/climateeu.html), the same data source we used for GAMM (KNMI Climate Explorer website) was here considered to keep the two methods consistent.…”

A Conceptual Framework for Conservation and Management of Moroccan Forest Genetic Resources Using Biogeography-Based Approach

“…Climate is generally considered a useful indirect indicator of genetic variability (De Dato et al 2018). It represents the most important driving force behind the spatial distribution of forest species, and reliable time series are one of the more valuable dataset for forest monitoring (Ferrara et al 2017).…”