Effects of firewood harvesting intensity on biodiversity and ecosystem services in shrublands of northern Patagonia

Background: Forest management has historically focused on provisioning of goods (e.g. timber, biomass), butthere is an increasing interest to manage forests also to maintain biodiversity and to provide other ecosystemservices (ES).Methods: We evaluated the effects of firewood harvesting intensity on biodiversity and different ES in threecontrasting shrubland sites in northern Patagonia (Argentina). At each site, four harvesting treatments, representingvarious levels of harvest intensity, were randomly assigned to eight permanent sample plots of 31.5m× 45 mduring 2013–2014.Results: We found that the effects of increasing harvesting intensity on plant diversity changed from negative topositive (and from nonlinear to more linear responses) with increasing site productivity. Harvesting intensityshowed contrasting effects on variables related to fire protection ecosystem service, since it reduced fuel amount(potentially reducing fire spread) but also reduced live fuel moisture content (potentially increasing flammability) atthe three sites. Two variables related to soil formation and protection ES, leaf litter cover and aerial soil cover,decreased with harvesting intensity at the three sites.Conclusions: We conclude that shrubland management for firewood production may enhance biodiversity withoutcompromising certain important ES. The intensity of harvesting should be determined according to site conditionsand forecasted impacts on biodiversity, fire and soil formation and protection.

Symbiotic interactions as drivers of trade-offs in plants: effects of fungal endophytes on tall fescue

Studying the controls on biomass allocation trade-offs in plants are important since they affect harvestable product yields and are critical to understanding symbiotic interactions.Epichloae fungal endophytes associate with cool-season grasses,growing systemically within the plant inter-cellular spaces and are transmitted through seeds.We explore the endophytes influence on the relationship between the plant reproductive and vegetative aboveground biomass(reproductive effort:RE)and on the trade-off between two components of the reproductive biomass,number and weight of panicles(RPN),using tall fescue as a model system.Naturally endophyte-colonized,manipulatively endophyte-free,and naturally endophyte-free plants from Northern European wild-populations together with the cultivar Kentucky-31 were grown under different environmental conditions(nutrients x water).The endophyte had an effect on the RPN(E+:6.19,ME-:4.68 and E-:4.40)which indicates how reproductive biomass is partitioned into number and mass of panicles,but not on RE(≈0.06).As expected,wild plants showed higher reproductive effort(≈0.06)compared to the cultivar KY-31(0.05),irrespective of endophyte presence.Endophyte-colonized plants had lighter panicles than endophyte-free plants,a pattern that was clear among low-yielding plants.Similarly,the tradeoff between RPN and RE was higher for endophytecolonized plants.This was again evident among plants with low RE indicating that colonized plants split the yield into either greater number of panicles and/or lighter panicles.The effect of vertically transmitted endophytes has earlier been studied as ratios(e.g.RE);however,our study shows that this approach may hide size-dependent endophyte effects on these relationships.Our study reveals that Neotyphodium endophyte affects trade-offs in tall fescue plants in a complex manner,and is influenced by a number of biological and abiotic factors.