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Variation of functional traits among species allows evaluating their life strategies. The whole-plant economic spectrum proposes coordination of the form and function across different plant organs to optimize a resource-use strategy. However, few studies have evaluated the coordination among woody species through functional traits from different plant organs. We evaluated variation and coordination of crown, leaf, stem, root and phenology trait values across woody species of the semi-arid Mediterranean matorral of Chile. We hypothesize that sclerophyllous and malacophyllous woody species vary and coordinate their trait values along an ecological dimension that separates their resource-use strategies from conservative to acquisitive, respectively. We analyzed the variation and correlation of 14 functional traits for 12-16 species. The functional trait values between sclerophyllous and malacophyllous species did not differ across the whole-plant economic spectrum. Traits were coordinated along multiple ecological dimensions. The first dimension was associated with the leaf economic spectrum and plant morphology, yet differed between sclerophyllous and malacophyllous species. Sclerophyllous species combined mostly conservative foliar trait values (longer leaf life span) with acquisitive morphological trait values (larger maximum plant height and longer lateral extension of roots), while malacophyllous species exhibited opposite combinations. The second dimension was associated with variation in phenology and root traits. This dimension separated species with conservative phenological and root trait values (delayed growth onset and deeper rooting depth) from opportunistic species with opposite trait values. The third dimension was coordinated by wood density and the leaf 13C - isotopic composition. This dimension separated the drought-tolerant species with high stem densities and higher leaf water use efficiency from opportunistic water-use species with opposite attributes. In contrast with our hypothesis, in the Chilean matorral the species can combine conservative and acquisitive trait values to use resources and coordinate their resource use strategies across multiple dimensions. This decoupling of plant strategies could occur because different organs and phenology are exposed to different environmental filters. [ABSTRACT FROM AUTHOR]

• Vascular wetland plants may substantially increase methane emissions by producing root exudates and easily degradable litter, and by providing a low resistance diffusion pathway via their aerenchyma. However, model studies have indicated that vascular plants can reduce methane emission when soil oxygen demand is exceeded by oxygen released from roots. Here, we tested whether these conditions occur in bogs dominated by cushion plants. • Root–methane interactions were studied by comparing methane emissions, stock and oxygen availability in depth profiles below lawns of either cushion plants or Sphagnum mosses in Patagonia. • Cushion plants, Astelia pumila and Donatia fascicularis, formed extensive root systems up to 120 cm in depth. The cold soil (< 10°C) and highly decomposed peat resulted in low microbial activity and oxygen consumption. In cushion plant lawns, high soil oxygen coincided with high root densities, but methane emissions were absent. In Sphagnum lawns, methane emissions were substantial. High methane concentrations were only found in soils without cushion plant roots. • This first methane study in Patagonian bog vegetation reveals lower emissions than expected. We conclude that cushion plants are capable of reducing methane emission on an ecosystem scale by thorough soil and methane oxidation. [ABSTRACT FROM AUTHOR]

• Functional dissimilarity was negatively related to forest productivity. • Increases in productivity were unlikely mediated by niche complementarity. • Functional identity (attributes of dominant species) drove productivity. • Dominant highly-competitive species with acquisitive attributes increased productivity. Biodiversity plays a pivotal role in forest productivity and, through it, on the provision of ecosystem services. Consequently, understanding the mechanisms by which biodiversity drives productivity is a challenge for sustainable forest management. It has been proposed that functional dissimilarity can increase forest productivity, particularly in water-limited ecosystems (as Mediterranean forests), where water stress might increase complementarity resource use among species (hypothesis of niche complementarity). Alternatively, strongly water-limited forests may favor the dominance of woody species with slow-growth and conservative resource-use trait values, which in turn, might increase plant community productivity proportionally to their biomass (hypothesis of mass-ratio). The effects of such mechanisms on productivity is yet understudied in water-limited forests. We assessed the effect of both previously described mechanisms on productivity in a semi-arid Mediterranean-type climate matorral of Chile through a trait-based approach. We hypothesized that: (1) higher dissimilarity of functional trait values of crowns, roots and phenology among woody species increases community productivity. Alternatively, (2) higher dominance of woody species of conservative trait values increases forest productivity. We installed twenty-three 25 × 25 m plots in the matorral of the National Reserve of "Roblería de Los Cobres de Loncha" located in the Coastal Range. Forest productivity was estimated as above-ground biomass changes between 2010 and 2017. The mean species pairwise dissimilarity (MPD) and the community-weighted mean trait values (CWM) were calculated for each single trait as surrogates of the hypotheses of niche complementarity and mass-ratio, respectively. Environmental variables (e.g. altitude, slope, precipitation) were included as potential drivers influencing productivity. We performed a selection procedure of multiple linear regression models based on the Akaike Information Criterion. Our findings show that higher forest productivity was related with higher trait similarity of plant maximum height and onset of growth among species. Besides, productivity increased with CWM values that reflect greater dominance of species exhibiting acquisitive traits (i.e. greater maximum plant height, lower wood density and earlier onset of growth) rather than conservative traits. Moreover, forest productivity increased with increasing altitude, precipitation and decreasing temperatures from 300 to 900 m. Therefore, in contrast with our hypotheses, productivity increased by greater trait similarity among dominant highly-competitive species - which might be favored by mesic conditions at middle altitudes of the Coastal Range. The sustainable management of semi-arid Mediterranean forests with the main focus on productivity should promote higher dominance of highly-competitive species with similar functional trait values in mesic conditions, and conservative species with greater trait functional dissimilarity to increase drought resistance in stressful environments. [ABSTRACT FROM AUTHOR]