Savannas after afforestation: Assessment of herbaceous community responses to wildfire versus native tree planting
Savannas after afforestation: Assessment of herbaceous community responses to wildfire versus native tree planting
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DOI：
10.1111/btp.12827
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发表时间：
2020-07
期刊：
影响因子：
2.1
通讯作者：
T. M. Haddad;R. Viani;Mário G. B. Cava;G. Durigan;J. Veldman
中科院分区：
文献类型：
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作者：
T. M. Haddad;R. Viani;Mário G. B. Cava;G. Durigan;J. Veldman
植树造林和防火是对热带稀树草原的普遍威胁。在巴西，限制规定燃烧的法律阻碍了塞拉多植物群落恢复过程中火灾的研究。我们利用 2017 年的一场野火来评估砍伐树木和火灾的潜力，以促进稀树草原草本植物群落在被外来人工林破坏后被动恢复。我们采样了一个被烧毁的松树种植园（Burned Plantation）；被收割并烧毁的前种植园（Harvested & Burned）；一个未烧毁的前种植园，已被收割，种植本地树木，并用除草剂处理以控制入侵草（本地树木种植）；以及两个作为参考群落的古老稀树草原。我们的结果证实，造林后地点的草本植物群落与古老的稀树草原有很大不同。在造林后的地点中，收获和燃烧的草本群落在组成上与古老的稀树草原更为相似，稀树草原植物的丰富度略高（每 50 平方米 3.8 种），并支持最大的本土草本植物覆盖（56％）。在树木覆盖评估中，草本群落恢复的这些积极趋势可能会被忽略：采伐和烧毁地点的树冠覆盖率为 6%（低于塞拉多稀树草原的典型覆盖率），而烧毁种植园和本土树木种植分别支持 34% 和 19% 的覆盖率。通过关注稀树草原草本植物，这些结果强调，在恢复塞拉多稀树草原的努力中，应该更加关注砍伐树木和火灾，而不仅仅是植树和防火。
Afforestation and fire exclusion are pervasive threats to tropical savannas. In Brazil, laws limiting prescribed burning hinder the study of fire in the restoration of Cerrado plant communities. We took advantage of a 2017 wildfire to evaluate the potential for tree cutting and fire to promote the passive restoration of savanna herbaceous plant communities after destruction by exotic tree plantations. We sampled a burned pine plantation (Burned Plantation); a former plantation that was harvested and burned (Harvested & Burned); an unburned former plantation that was harvested, planted with native trees, and treated with herbicide to control invasive grasses (Native Tree Planting); and two old‐growth savannas which served as reference communities. Our results confirm that herbaceous plant communities on post‐afforestation sites are very different from old‐growth savannas. Among post‐afforestation sites, Harvested & Burned herbaceous communities were modestly more similar in composition to old‐growth savannas, had slightly higher richness of savanna plants (3.8 species per 50‐m2), and supported the greatest cover of native herbaceous plants (56%). These positive trends in herbaceous community recovery would be missed in assessments of tree cover: whereas canopy cover in the Harvested & Burned site was 6% (less than typical of savannas of the Cerrado), the Burned Plantation and Native Tree Planting supported 34% and 19% cover, respectively. By focusing on savanna herbaceous plants, these results highlight that tree cutting and fire, not simply tree planting and fire exclusion, should receive greater attention in efforts to restore savannas of the Cerrado.