Conservation values of understory vascular plants in even- and uneven-aged Nothofagus antarctica forests

Abstract

Usually, stands with aging trees are considered forests with higher conservation values, regardless their structural diversity and other functional attributes. Natural stands present a wide range of age structures, from even-aged stands growing at different development growth phases (e.g. CO = stands at initial or final optimum development growth phase, MD = stands at mature or decaying development growth phases) to uneven-aged stands with mixed development growth phases (e.g. UOG = stands combining mature or decaying development growth phases with initial or final optimum development growth phases, UMD = stands combining only mature and decaying development growth phases). The aim of this work was to compare richness and cover of understory vascular plants of evenand uneven-aged stands of Nothofagus antarctica (n ˜ire) forests in Tierra del Fuego (Argentina), and relate these characteristics with abiotic, soil and forest structure variables. A total of 75 stands were sampled across the natural range distribution of the forests, where understory (point intercept method), forest structure (angle count sampling and eye-fish photos) and environmental (soil) variables were measured. 17 one-way ANOVAs were conducted using Tukey test at p \ 0.05 to compare the means. Among forest structure and environmental variables, cover (F = 4.3, p = 0.007), radiation (F = 4.4, p = 0.006), phosphorous (F = 3.9, p = 0.012), tree density (F = 10.3, p \ 0.001), tree diameter (F = 10.3, p \ 0.001) and stand growth (F = 4.9, p = 0.004) showed significant differences, and in general with a positive or negative trend across the MD-UMD-UOG-CO gradient. Total (F = 6.5, p \ 0.001) and native species richness of the understory (F = 7.2, p \ 0.001) were significantly different among forest types, where UMD [ UOG [ MD [ CO (17-28 total, and 13-24 native species, respectively). Neither exotic species richness (4-5 species) nor understory cover significantly changed among treatments (total, dicots, ferns and bryophytes). However, monocots cover significantly differed among treatments (F = 3.9, p = 0.012), where UMD [ MD [ UOG [ CO. Finally, indicator species cover for environmental degradation did not present significant differences (F = 2.1, p = 0.106), but they were positive related to forests growing in mature stages. We concluded that uneven-aged stands presented significantly higher conservation values compared to even-aged stands, where mature/decay stands have better conservation values Communicated by Lilly O Rodriguez Bayona. This articlebelongs to the Topical Collection: Forest and plantation biodiversity.

Changes in forest structure values along the natural cycle and different management strategies in Nothofagus antarctica forests

“…The studied forests follow a simple natural dynamic, based on gaps that can generate even-or uneven-aged structures depending on tree recruitment over time in the stands (Ivancich, 2013;Peri et al, 2017;Martínez Pastur et al, 2020b). It was possible to identify four even-aged phases during the natural growth life-cycle (Fig.…”

Experimental Examination of Vegetative Propagation Methods of Nothofagus antarctica (G. Forst.) Oerst. for Restoration of Fire-Damaged Forest in Torres del Paine National Park, Chile

“…Remainders of native Antarctic beech forests having high conservation values [6] are protected primarily in national parks, including Torres del Paine National Park in Chilean Patagonia, at 51 • S latitude. Despite that paleo-environmental research indicates that fires have been a frequent natural phenomenon in the park [7], Antarctic beech forests are not naturally adapted to fire impact [8].…”

Forest phenoclusters for Argentina based on vegetation phenology and climate

“…However, many species groups cover large areas (e.g., more than 2000 km 2 ) and their growth exhibits diverse natural gradients (Rosas, Peri, Bahamonde, et al, 2019). The main strategy for biodiversity conservation has been designation of national parks (e.g., a land‐sparing strategy), based on the hope that one or a few large protected areas can safeguard a representative set of ecosystem functions and biodiversity of the protected forest types (Martínez Pastur, Rosas, et al, 2020; Martínez Pastur, Schlichter, et al, 2020). These management and conservation planning strategies have failed at the landscape level in Argentina, because protected areas cannot protect all the biodiversity found in each forest type (Lorenzo et al, 2018).…”