Positive biodiversity-productivity relationship predominant in global forests

Abstract

The biodiversity-productivity relationship (BPR) is foundational to our understanding of the global extinction crisis and its impacts on ecosystem functioning. Understanding BPR is critical for the accurate valuation and effective conservation of biodiversity. Using ground-sourced data from 777,126 permanent plots, spanning 44 countries and most terrestrial biomes, we reveal a globally consistent positive concave-down BPR, showing that continued biodiversity loss would result in an accelerating decline in forest productivity worldwide. The value of biodiversity in maintaining commercial forest productivity alone—US$166 billion to 490 billion per year according to our estimation—is more than twice what it would cost to implement effective global conservation. This highlights the need for a worldwide reassessment of biodiversity values, forest management strategies, and conservation priorities. (Résumé d'auteur

Forest biodiversity, ecosystem functioning and the provision of ecosystem services

“…Hundreds of studies have addressed the effects of tree species diversity on many forest ecosystem functions, including primary production (e.g., Liang et al 2016). In this very active field of research, the statement that tree diversity can improve ''forest ecosystem function and (associated) services'' has become very common.…”

“…Productivity is often higher in mixtures than in monocultures, and this effect can increase with tree-species richness (Forrester and Bauhus 2016;Liang et al 2016). A recent global meta-analysis of mixture-monoculture comparisons found that the productivity of mixtures was, on average, 26.5% greater than the mean of the respective monocultures (i.e., overyielding) and 9.8% greater than the most productive of the respective monocultures (i.e., transgressive overyielding) (this excludes very young mixtures where the effects were smaller) (Gritti et al, cited in Pretzsch and Forrester 2017).…”

“…Collectively, these trends in forest cover and condition are a major concern, not only because of the implications for the conservation of biodiversity, but also because forests provide a wide range of critically important ecosystem services such as climate regulation, biomass production, water supply and purification, pollination, and the provision of habitats for forest species Thompson et al 2011;Brockerhoff et al 2013;Decocq et al 2016;Liang et al 2016;Mori et al 2017). There is also increasing evidence that the provision of ecosystem services is related to aspects of biodiversity; there is a positive relationship between biodiversity and most ecosystem services (e.g., Hooper et al 2005;Balvanera et al 2006;Isbell et al 2011;Gamfeldt et al 2013).…”

Do ecosystem services provide an added value compared to existing forest planning approaches in Central Europe?

“…We thereby assume that it will be more likely suitable for economic, environmental, and societal changes. For example, a more biodiverse forest may ensure a higher longterm productivity for timber (Liang et al 2016). For current societal demand, missing prioritization (multifunctional forestry) might not completely fulfill single stakeholders' preferences because it is necessary to balance different societal preferences as requested by Gamborg and Larsen (2003).…”

EuMIXFOR empirical forest mensuration and ring width data from pure and mixed stands of Scots pine (Pinus sylvestris L.) and European beech (Fagus sylvatica L.) through Europe

“…productivity (Río and Sterba 2009;Pretzsch et al 2010Pretzsch et al , 2013Perot 2011, Condés et al 2013;Bielak et al 2014;Liang et al 2016), structural diversity (Río et al 2016a) or stability (Knoke et al 2008). However, the underlying processes are often still poorly understood.…”