Increased evapotranspiration demand in a Mediterranean climate might cause a decline in fungal yields under global warming

Abstract

Wild fungi play a critical role in forest ecosystems, and its recollection is a relevant economic activity. Understanding fungal response to climate is necessary in order to predict future fungal production in Mediterranean forests under climate change scenarios. We used a 15-year data set to model the relationship between climate and epigeous fungal abundance and productivity, for mycorrhizal and saprotrophic guilds in a Mediterranean pine forest. The obtained models were used to predict fungal productivity for the 2021-2080 period by means of regional climate change models. Simple models based on early spring temperature and summer-autumn rainfall could provide accurate estimates for fungal abundance and productivity. Models including rainfall and climatic water balance showed similar results and explanatory power for the analyzed 15-year period. However, their predictions for the 2021-2080 period diverged. Rainfall-based models predicted a maintenance of fungal yield, whereas water balance-based models predicted a steady decrease of fungal productivity under a global warming scenario. Under Mediterranean conditions fungi responded to weather conditions in two distinct periods: early spring and late summer-autumn, suggesting a bimodal pattern of growth. Saprotrophic and mycorrhizal fungi showed differences in the climatic control. Increased atmospheric evaporative demand due to global warming might lead to a drop in fungal yields during the 21st century.

Meteorological conditions and site characteristics driving edible mushroom production in Pinus pinaster forests of Central Spain

“…Our results indicated that, even though mushroom production occurred across all stand ages, maximum yield of marketed and L. group deliciosus mushrooms occurred in younger stands. This is in line with previous research on the effect of stand age on the yield of L. deliciosus and other ectomycorrhizal fungi (Smith et al, 2002;Fern andez-Toir an et al, 2006;Bonet et al, 2010;Agreda et al, 2013), although some authors have also reported high yields at different stand ages (Zamora-Martínez and Nieto de Pascual, 1995;Bonet et al, 2004;Martínez-Peña et al, 2012a). Since marketed and L. group deliciosus species are all ectomycorrhizal fungi, they may get more carbohydrates from the more photosynthetically active trees in young stands.…”

“…The models reflect the importance of not only the amount of rainfall, but also its distribution, on mushroom production. Previous research has also indicated that mushroom production is strongly related to weather conditions, especially rainfall during the autumn season (Bonet et al, 2004;Martínez de Arag on et al, 2007;Bonet et al, 2012;Martínez-Peña et al, 2012b;Agreda et al, 2015). Although previous research has reported that temperature may be another important driver of mushroom yield (Martínez-Peña et al, 2012b;Hern andez-Rodríguez et al, 2015), no significant effect of temperature was found in this study.…”

“…Fifteen sample plots, established as described in Fern andezToir an et al (2006) and Agreda et al (2013), were used to represent different stand age classes. Each plot covered an area of 150 m 2 , with a rectangular shape (5 Â 30 m).…”

“…Indeed, the market demand for many ectomycorrhizal fungi has increased to the extent that the value of forest fungi may equal or even surpass the value of timber (Alexander et al, 2002;Palahí et al, 2009). Central Spain, where mushroom harvesting has become a major activity in Pinus pinaster forests (Fern andez-Toir an et al, 2006), is not an exception, and the revenue from mushroom collection is approaching the return expected from timber, which has been the most important forest product during the last decade ( Agreda et al, 2013). Some of the fungi found in P. pinaster forests, such as Lactarius group deliciosus, are highly appreciated locally and internationally, and their trade has become an important complementary economic activity in many regions (Cai et al, 2011;Martínez de Arag on et al, 2011;Voces et al, 2011).…”

“…In general, there are very few models in the literature aiming at predicting the yield of nonwood forest products to be used in forest planning (Bravo et al, 2011). Although these kinds of studies are rather recent, several mushroom yield models have been published so far (Bonet et al, 2008(Bonet et al, , 2010(Bonet et al, , 2012Martínez-Peña et al, 2012b;de-Miguel et al, 2014;Agreda et al, 2015;Hern andez-Rodríguez et al, 2015). Mushroom yield modeling requires large quantities of data over several years in order to provide reliable estimates, especially if the models are intended to account for the effect of meteorological conditions.…”