Active Restoration Initiates High Quality Forest Succession in a Deforested Landscape in Amazonia

Amazonia is well known for its high natural regeneration capacity; for this reason, passive restoration is normally recommended for the recovery of its degraded forests. However, highly deforested landscapes in southern Amazonia require active restoration. Since restoration methods can shape the quality and speed of early forest recovery, this study aimed to verify how active restoration pushes sites stably covered with exotic grasses towards forest recovery. We evaluated early forest succession at active restoration sites, i.e., soil plowing, direct seeding of pioneer species, and seedling stock planting at low density. We analyzed forest structure, diversity, and species composition in two age classes, 0.5–3.5 and 4.5–7.5 years old. As reference, we evaluated sites able to naturally regenerate in the same region. We sampled 36 active restoration and 31 natural regeneration sites along the Madeira River, southern Amazonia. Active restoration triggered succession to similar or higher levels of forest structure than sites where natural regeneration was taking place. The most dominant species did not overlap between active restoration and natural regeneration sites. The overall composition of species was different between the two restoration methods. Dominant species and size class distribution show that active restoration is performing successfully. Soil preparation combined with a high availability of seeds of pioneer trees resulted in a high stem density and basal area of facilitative pioneer trees. Planted seedlings added species diversity and increased density of large trees. Interventions to increase the odds of natural regeneration can be effective for non-regenerating sites in resilient landscapes.

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Active Restoration Initiates High Quality Forest Succession In A Deforested Landscape In Amazonia

10.21203/rs.3.rs-557683/v1 ◽

2021 ◽

Author(s):

Daniel Luis Mascia Vieira ◽

Silvia Rodrigues ◽

Catarina Conte Jakovac ◽

Gustavo Paiva Evangelista da Rocha ◽

Fagno Reis ◽

...

Keyword(s):

Forest Structure ◽

Natural Regeneration ◽

Dominant Species ◽

Forest Succession ◽

Forest Recovery ◽

Stem Density ◽

Active Restoration ◽

Large Trees ◽

Pioneer Trees ◽

Southern Amazonia

Abstract Background: Amazonia is well known for its high natural regeneration capacity; for this reason, passive restoration is normally recommended for the recovery of its degraded forests. However, highly deforested landscapes in southern Amazonia require active restoration. Since restoration methods can shape the quality and speed of early forest recovery, this study aimed to verify how active restoration pushes non-resilient sites towards forest recovery. Methods: We evaluated early forest succession at active restoration sites, i.e. soil plowing, direct seeding of pioneer species and seedling stock planting at low density. We analyzed forest structure, diversity and species composition in two age classes, 0.5 – 3.5 and 4.5 – 7.5 years old. As reference, we evaluated natural regeneration as performed on more resilient sites in the same region. We sampled 36 active restoration and 31 natural regeneration sites along the Madeira river, southern Amazonia. Results: Active restoration triggered succession to similar or higher levels of forest structure than sites where natural regeneration was taking place. The most dominant species did not overlap between active restoration and natural regeneration sites. The overall composition of species was different between the two restoration methods. Dominant species and size class distribution indicate that active restoration is performing successfully. Conclusions: Soil preparation combined with a high availability of seeds of pioneer trees resulted in a high stem density and basal area of facilitative pioneer trees. Planted seedlings added species diversity and increased density of large trees. Interventions to increase the odds of natural regeneration can be effective for non-resilient sites located in resilient landscapes.

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Big trees drive forest structure patterns across a lowland Amazon regrowth gradient

Scientific Reports ◽

10.1038/s41598-021-83030-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Tassiana Maylla Fontoura Caron ◽

Victor Juan Ulises Rodriguez Chuma ◽

Alexander Arévalo Sandi ◽

Darren Norris

Keyword(s):

Forest Structure ◽

Natural Regeneration ◽

Basal Area ◽

Significant Decline ◽

Forest Regrowth ◽

Large Trees ◽

Amazonian Forests ◽

Mammal Diversity ◽

Structure Patterns ◽

Plot Type

AbstractDegraded Amazonian forests can take decades to recover and the ecological results of natural regeneration are still uncertain. Here we use field data collected across 15 lowland Amazon smallholder properties to examine the relationships between forest structure, mammal diversity, regrowth type, regrowth age, topography and hydrology. Forest structure was quantified together with mammal diversity in 30 paired regrowth-control plots. Forest regrowth stage was classified into three groups: late second-regrowth, early second-regrowth and abandoned pasture. Basal area in regrowth plots remained less than half that recorded in control plots even after 20–25 years. Although basal area did increase in sequence from pasture, early to late-regrowth plots, there was a significant decline in basal area of late-regrowth control plots associated with a decline in the proportion of large trees. Variation in different forest structure responses was explained by contrasting variables, with the proportion of small trees (DBH < 20 cm) most strongly explained by topography (altitude and slope) whereas the proportion of large trees (DBH > 60 cm) was explained by plot type (control vs. regrowth) and regrowth class. These findings support calls for increased efforts to actively conserve large trees to avoid retrogressive succession around edges of degraded Amazon forests.

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Big trees drive forest structure patterns across a lowland Amazon regrowth gradient

10.1101/2020.04.23.058289 ◽

2020 ◽

Author(s):

Tassiana Maylla Fontoura Caron ◽

Victor Juan Ulises Rodriguez Chuma ◽

Alexander Arévalo Sandi ◽

Darren Norris

Keyword(s):

Forest Structure ◽

Natural Regeneration ◽

Basal Area ◽

Significant Decline ◽

Forest Regrowth ◽

Large Trees ◽

Amazonian Forests ◽

Mammal Diversity ◽

Structure Patterns ◽

Plot Type

AbstractDegraded Amazonian forests can take decades to recover and the ecological results of natural regeneration are still uncertain. Here we use field data collected across 15 lowland Amazon smallholder properties to examine the relationships between forest structure, mammal diversity, regrowth type, regrowth age, topography and hydrography. Forest structure was quantified together with mammal diversity in 30 paired regrowth-control plots. Forest regrowth stage was classified into three groups: late second-regrowth, early second-regrowth and abandoned pasture. Basal area in regrowth plots remained less than half that recorded in control plots even after 20-25 years. Although basal area did increase in sequence from pasture, early to late-regrowth plots, there was a significant decline in basal area of late-regrowth control plots associated with a decline in the proportion of large trees. There was also contrasting support for different non-mutually exclusive hypotheses, with proportion of small trees (DBH <20cm) most strongly supported by topography (altitude and slope) whereas the proportion of large trees (DBH >60cm) supported by plot type and regrowth class. These findings support calls for increased efforts to actively conserve large trees to avoid retrogressive succession around edges of degraded Amazon forests.

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Temporal Changes in Community Structure over a 5-Year Successional Stage in a Subtropical Forest

Forests ◽

10.3390/f11040438 ◽

2020 ◽

Vol 11 (4) ◽

pp. 438

Author(s):

Mingfeng Xu ◽

Ting Liu ◽

Peiyun Xie ◽

Hongyu Chen ◽

Zhiyao Su

Keyword(s):

Community Structure ◽

Forest Management ◽

Total Phosphorus ◽

Forest Structure ◽

Forest Succession ◽

Driving Factors ◽

Tree Biomass ◽

Large Tree ◽

Large Trees ◽

Abundance And Diversity

In the context of global warming, the changes of forest structure, diversity, and productivity along with forest succession have always been a topic of interest for many researchers. Studying the changes in community structure, biomass, and diversity of different diameter at breast height (DBH) classes in subtropical mountainous forests during forest succession can provide data in support of future forest succession predictions and forest management. We analyzed the changes of three DBH classes in a 10-ha plot while studying subtropical mountainous forest succession in 2012 and 2017. The results showed that during forest succession, the community abundance and richness significantly decreased while biomass increased slightly. Among the three DBH classes, changes were the greatest in small trees, followed by large trees, and then medium-sized trees. The abundance, biomass, richness, and Shannon–Wiener index of small trees all decreased significantly. In forests with medium-sized trees, biomass decreased significantly and abundance did not change significantly. In large trees, abundance and biomass increased significantly. Changes were observed in environmental driving factors during forest succession. In 2012, driving factors with significant effects included total phosphorus, transmitted direct solar radiation, organic matter, and capillary water capacity. In 2017, two driving factors were total phosphorus and total potassium while the main driving factor was still total phosphorus. The results showed that during forest succession the abundance and diversity of small trees were principal components of community abundance and diversity. A reduction in small-tree abundance and diversity will decrease community abundance and diversity. Large-tree biomass was a principal component of community biomass; accumulation of large-tree biomass will increase community biomass. Schima superba Gardner and Champ. and Castanopsis carlesii (Hemsl.) Hayata are the main dominant species in this area, which can quickly form stable communities. S. superba is also a fire-resistant tree species. Therefore, in natural forest management, planting of S. superba and C. carlesii in the secondary bare land can be considered. In addition, the evergreen broad-leaved forest can be recovered to the forest structure and productivity level before selective cutting, which provides important inspiration for forest management in the region.

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Forest restoration in southern Amazonia: Soil preparation triggers natural regeneration

Forest Ecology and Management ◽

10.1016/j.foreco.2018.10.049 ◽

2019 ◽

Vol 433 ◽

pp. 93-104 ◽

Cited By ~ 8

Author(s):

Gustavo Mariano Rezende ◽

Daniel Luis Mascia Vieira

Keyword(s):

Natural Regeneration ◽

Forest Restoration ◽

Soil Preparation ◽

Southern Amazonia

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Natural Regeneration After Gold Mining in the Peruvian Amazon: Implications for Restoration of Tropical Forests

Frontiers in Forests and Global Change ◽

10.3389/ffgc.2021.594627 ◽

2021 ◽

Vol 4 ◽

Author(s):

Roger Chambi-Legoas ◽

Daigard Ricardo Ortega Rodriguez ◽

Francisco de Marques de Figueiredo ◽

Joel Peña Valdeiglesias ◽

Percy Amílcar Zevallos Pollito ◽

...

Keyword(s):

Tropical Forests ◽

Natural Regeneration ◽

Forest Restoration ◽

Gold Mining ◽

Forest Recovery ◽

Regeneration Process ◽

Peruvian Amazon ◽

Secondary Species ◽

Number Of Species ◽

Madre De Dios

Context: Gold mining is the most destructive activity in the natural forests of the Madre de Dios region in the southeastern Peruvian Amazon. Understanding the natural regeneration process of these degraded areas is necessary to develop forest restoration projects in such conditions.Aims: We aimed to evaluate forest recovery and identify the successional and structure patterns of vegetation governing natural regeneration over time.Methods: Structure, composition, richness, diversity, and successional status were evaluated in abandoned artisanal gold mine areas in Madre de Dios, southeastern Peru. Vegetation data were recorded in 61 plots of 250 m2 established in five sites varying from 1 to 19 years of abandonment. Vegetation in abandoned areas was compared with six undisturbed forests evaluated in previous inventories.Results: In the mining lands, tree density and basal area recovered quickly, while species richness and composition were slow. Forest recovery is an initial stage of transition from pioneer to early secondary species until at least 19 years after abandonment. The most abundant and frequent species were the fast-growing species Ochroma pyramidale and Cecropia engleriana. These species could be considered potential candidates to promote restoration plans. Pioneer species represented 63% of the number of species in plots of 1–4 years, 57% in plots of 5–7 years, and 50% in plots of 8–19 years. Early and late secondary species represented 34 and 16%, respectively, of the number of species in plots of 8–19 years. Abandoned mining and reference plots present less than 5% of species in common.Conclusion: Our results highlight a slow natural regeneration process in areas for up to 19 years after gold mining. Species from different successional statuses were identified as potential candidates for recovering vegetation in such areas. Our findings may have important implications for further research focusing on the ecological restoration in tropical forests severely degraded by gold mining.

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Forest Climax Phenomenon: An Invariance of Scale

Forests ◽

10.3390/f11010056 ◽

2020 ◽

Vol 11 (1) ◽

pp. 56 ◽

Cited By ~ 1

Author(s):

Raimundas Petrokas

Keyword(s):

Natural Regeneration ◽

Forest Regeneration ◽

Forest Succession ◽

Initial Conditions ◽

Forest Tree ◽

Tree Regeneration ◽

Red Queen Hypothesis ◽

Habitat Dynamics ◽

Process Pattern ◽

Sensitivity To Initial Conditions

We can think of forests as multiscale multispecies networks, constantly evolving toward a climax or potential natural community—the successional process-pattern of natural regeneration that exhibits sensitivity to initial conditions. This is why I look into forest succession in light of the Red Queen hypothesis and focus on the key aspects of ecological self-organisation: dynamical criticality, evolvability and intransitivity. The idea of the review is that forest climax should be associated with habitat dynamics driven by a large continuum of ecologically equivalent time scales, so that the same ecological conclusions could be drawn statistically from any scale. A synthesis of the literature is undertaken in order to (1) present the framework for assessing habitat dynamics and (2) present the types of successional trajectories based on tree regeneration mode in forest gaps. In general, there are four types of successional trajectories within the process-pattern of forest regeneration that exhibits sensitivity to initial conditions: advance reproduction specialists, advance reproduction generalists, early reproduction generalists and early reproduction specialists. A successional trajectory is an expression of a fractal connectivity among certain patterns of natural regeneration in the multiscale multispecies networks of landscape habitats. Theoretically, the organically derived measures of pattern diversity, integrity and complexity, determined by the rates of recruitment, growth and mortality of forest tree species, are the means to test the efficacy of specific interventions to avert the disturbance-related decline in forest regeneration. That is of relevance to the emerging field of biocomplexity research.

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Structural composition and distribution of tree species of Dudhpukuria-Dhopachori Wildlife Sanctuary, Chittagong, Bangladesh

Journal of Biodiversity Conservation and Bioresource Management ◽

10.3329/jbcbm.v3i1.36757 ◽

2018 ◽

Vol 3 (1) ◽

pp. 17-30 ◽

Cited By ~ 1

Author(s):

MA Hossain ◽

MK Hossain ◽

MS Alam ◽

MM Abdullah Al Mamun

Keyword(s):

Tree Species ◽

Natural Regeneration ◽

Sustainable Management ◽

Dominant Species ◽

The Other ◽

Wildlife Sanctuary ◽

Height Range ◽

Structural Composition ◽

Number Of Species ◽

Successful Recruitment

Structural composition based on diameter and height class distribution of the tree species of Dudhpukuria-Dhopachori Wildlife Sanctuary, Chittagong, Bangladesh was assessed. A total of 183 tree species having ≥ 10 DBH belonging to 125 genera and 48 families was recorded from the study area. Different species were found to dominate in different DBH classes, i.e. Aporosa wallichii (4.06%), Artocarpus chama (1.54%) and Dillenia pentagyna (0.38%) dominated 10 - < 25 cm, 25 - < 40 cm and 40 - < 55 cm DBH, respectively. Swintonia floribunda was found in maximum (7 out of 8) number of DBH classes. Both the percentage of tree individuals (73.18%) and number of species (169) were highest in 10-24.5cm DBH range. Similarly, Dipterocarpus turbinatus (14.5-24.4m and 24.5-34.4m) and Swintonia floribunda (34.5-44.4m and 44.5-54.4m) were dominant in two height ranges each. On the other hand, height range 4.5 - 14.4 m was dominated by Aporosa wallichii (4.36%). Dipterocarpus costatus, Artocarpus chama, Syzygium firmum and Bombax insigne were found in all the height classes. Both the number of tree species and number of individual stems (167 species; 1,684 individuals) were highest in the height range of 4.5-14.4m. The number of species and tree individuals decreased linearly with increasing height. All these indicate that, there was a sustainable natural regeneration and successful recruitment of Aporosa wallichii, Dipterocarpus turbinatus, Lithocarpus acuminata, Grewia nervosa and Artocarpus chama in Dudhpukuria-Dhopachori Wildlife Sanctuary. Dipterocarpus turbinatus was found as dominant species as it constitures maximum (5.56%) percentage of all tree individuals. The findings of the study may be useful for protection, conservation and sustainable management of Dudhpukuria-Dhopachori Wildlife Sanctuary.J. Biodivers. Conserv. Bioresour. Manag. 2017, 3(1): 17-30

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