Tree diversity supporting forest adaptation under climate change

Biodiversity may enhance forest functioning and services in several aspects. Our results, however, suggest that the positive role of biodiversity can be a consequence of different mechanisms that are contingent upon environmental conditions and other factors. For example, biodiversity can be relevant in buffering climate change by means of a variety of mechanisms. Uncertainty around future climate conditions is high with respect to precipitation  so it is not easy to know which species or combination of species will perform better in the future. It is important to ensure, in the face of uncertainty, that not only a high number of species if present but rather different functional strategies. This may improve the resilience of forest ecosystems and the ability of forest to adapt to new conditions.

It is well known that different species have different strategies to cope with drought. This premise suggests that an increasing frequency of drought events will demand species able to overcome this kind of impacts in forests. However, temperate or boreal species are not well adapted species to drought, so including stress-tolerant species in these type forests would provide higher resistance capacity in this type forests. Similarly water spenders or water conservative species may overcome different components of aridity (i.e. long versus intense droughts). Resprouter species such as holm oak are also favoured under some scenarios as they can reestablish vegetatively after ramet death.

Undoubtedly, tree species mixture affects forest productivity by means of several mechanisms. Yet, the effect of an increasing number of species in the stand can be either positive or negative for overall stand productivity depending on tree size, environmental conditions and species. Our results suggest that different sized trees have different growth responses to diversity and this can be observed at a latitudinal scale in Europe. For example, diversity seems to be predominantly positive for small trees in the Boreal biome although the contrary is true in the Mediterranean. Conversely, negative effects of diversity seem to be predominant for large trees in Boreal forests while the opposite is true in the Mediterranean. Curiously, positive and negative effects of diversity are equally likely for both small and large trees in cool temperate forests. Humans may use this mechanism to enhance forest productivity (i.e. including ontogenetic responses to diversity into management prescriptions). For example, diversity can naturally enhance forest regeneration in boreal forests and thinning may minimize negative effects of diversity on individual tree growth. Accordingly, diversity in Mediterranean forest would be important to enhance forest productivity in mature stands but no much in earlier stages where selection effects acting on drought filtering might become more relevant.

Biological diversity, or the shorter "biodiversity," means the diversity, or variety, of plants and animals and other living things in a particular area or region. It describes the variability among living organisms from all sources, including terrestrial, marine, and other aquatic ecosystems and the ecological complexes of which they are part. Biodiversity includes diversity within species, between species, and between ecosystems. (MA, 2003)
A condition describes a requirement or requisite. wiki
The controversy surrounding the issues arises because it involves the convergence of three 'storms' 1) the global problem 2) its intergeneration dimension and 3) the inadequacies of the theoretical models ( Gardier SM 2011).
Any or all of the forms of water particles, whether liquid or solid, that fall from the atmosphere (e.g., rain, hail, snow or sleet). It is a major class of hydrometeor, but it is distinguished from cloud, fog, dew, rime, frost, etc., in that it must fall. It is distinguished from cloud and virga in that it must reach the ground. wiki
The level of disturbance that an ecosystem can undergo without crossing a threshold to a situation with different structure or outputs. Resilience depends on ecological dynamics as well as the organizational and institutional capacity to understand, manage, and respond to these dynamics. ( MA 2003)
The capacity of an ecosystem to withstand the impacts of drivers without displacement from its present state. ( MA 2003)
Describes the number of different species that are represented in a given community or population. The effective number of species (trees, plants, mosses,...) refers to the number of equally abundant species needed to obtain the same mean proportional species abundance as that observed in specific community or population (where all species may not be equally abundant). Species diversity consists of two components: species richness and species evenness. Species richness is a simple count of species, whereas species evenness quantifies how equal the abundances of the species are.
A cultural treatment made to reduce stand density of trees primarily to improve growth, enhance forest health, or recover potential mortality. http://dictionaryofforestry.org/dict/term/thinning
Miguel A. Zavala

About FunDivEurope

Learn more about the FunDivEurope project:

About this Platform

Get in touch with the FunDiVEurope Knowledge Transfer Platform and read the latest news from the site administrators: