Scholarlink

<p>The selection system is a suitable silvicultural approach to managing forests dominated by shade-tolerant and mid-tolerant tree species and to sustain complex and diverse forests and provide valuable large-sized timer of high-quality species. Many forests at intermediate and late stages of stand dynamics in south-central Chile have the potential to be successfully managed with selection cuttings. To test the effectiveness of selection cuttings in these forests, we set two experiments at two sites (Llancahue and Los Riscos) at 250–350 m a.s.l. in the Coastal range of Chile (40–41° S Lat.). At each site we established eight 2000 m<sup>2</sup> plots (40 × 50 m) following the BDq approach, with the same maximum residual diameter (D = 80 cm) and expected residual structure (q = 1.3), but different residual basal areas (B = 40 (LRBA) and 60 (HRBA) m<sup>2</sup> ha<sup>−1</sup>) in four plots in each case. The main hypothesis was that with lower basal area there would be greater growth and more regeneration of mid-tolerant species. The working hypothesis was that LRBA plots would have greater diameter growth, regeneration and ingrowth of mid-tolerant species. For 11 years after cuttings, we measured three periods in Llancahue and two in Los Riscos to test this hypothesis. Both sites had similar tree species composition, but Llancahue had more species that are associated with more humid conditions. At both sites average diameter growth rates were similar, with mid-tolerant species having higher growth in the intermediate diameter class (&gt; 20–50 cm) and shade-tolerant species in the large diameter class (&gt; 50–80 cm). Total density of regeneration, saplings and ingrowth were more abundant in Llancahue, but for mid-tolerant species numbers were similar. Most importantly, only at Llancahue growth and regeneration were sensitive to basal area, with greater values in LRBA plots. Basal area and volume growth did not differ between plots with different basal areas and showed contrasting trends. Overall, results suggest that even lower residual basal areas (B) or other modifications of the BDq approach may be needed to improve success in growing mid-tolerant species, and cutting cycles should be defined accordingly.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Results and perspectives of the selection system after a decade of implementation in Valdivian temperate rainforests

  • 期刊论文

  • 发表日期：

    2025年7月7日

查看全文
  • Pablo J. Donoso,
  • Tomás Riquelme-Buitano

摘要

The selection system is a suitable silvicultural approach to managing forests dominated by shade-tolerant and mid-tolerant tree species and to sustain complex and diverse forests and provide valuable large-sized timer of high-quality species. Many forests at intermediate and late stages of stand dynamics in south-central Chile have the potential to be successfully managed with selection cuttings. To test the effectiveness of selection cuttings in these forests, we set two experiments at two sites (Llancahue and Los Riscos) at 250–350 m a.s.l. in the Coastal range of Chile (40–41° S Lat.). At each site we established eight 2000 m2 plots (40 × 50 m) following the BDq approach, with the same maximum residual diameter (D = 80 cm) and expected residual structure (q = 1.3), but different residual basal areas (B = 40 (LRBA) and 60 (HRBA) m2 ha−1) in four plots in each case. The main hypothesis was that with lower basal area there would be greater growth and more regeneration of mid-tolerant species. The working hypothesis was that LRBA plots would have greater diameter growth, regeneration and ingrowth of mid-tolerant species. For 11 years after cuttings, we measured three periods in Llancahue and two in Los Riscos to test this hypothesis. Both sites had similar tree species composition, but Llancahue had more species that are associated with more humid conditions. At both sites average diameter growth rates were similar, with mid-tolerant species having higher growth in the intermediate diameter class (> 20–50 cm) and shade-tolerant species in the large diameter class (> 50–80 cm). Total density of regeneration, saplings and ingrowth were more abundant in Llancahue, but for mid-tolerant species numbers were similar. Most importantly, only at Llancahue growth and regeneration were sensitive to basal area, with greater values in LRBA plots. Basal area and volume growth did not differ between plots with different basal areas and showed contrasting trends. Overall, results suggest that even lower residual basal areas (B) or other modifications of the BDq approach may be needed to improve success in growing mid-tolerant species, and cutting cycles should be defined accordingly.