| Full text | |
| Author(s): Show less - |
Vedovato, Laura B.
;
Aragao, Luiz E. O. C.
;
Almeida, Danilo R. A.
;
Bartholomew, David C.
;
Assis, Mauro
;
Dalagnol, Ricardo
;
Gorgens, Eric B.
;
Silva-Junior, Celso H. L.
;
Ometto, Jean P.
;
Pontes-Lopes, Aline
;
Silva, Carlos A.
;
Valbuena, Ruben
;
Feldpausch, Ted R.
Total Authors: 13
|
| Document type: | Journal article |
| Source: | REMOTE SENSING IN ECOLOGY AND CONSERVATION; v. N/A, p. 17-pg., 2025-02-15. |
| Abstract | |
Secondary forests in the Amazon are important carbon sinks, biodiversity reservoirs, and connections between forest fragments. However, their regrowth is highly threatened by fire. Using airborne laser scanning (ALS), surveyed between 2016 and 2018, we analyzed canopy metrics in burned (fires occurred between 2001 and 2018) and unburned secondary forests across different successional stages and their ability to recover after fire. We assessed maximum and mean canopy height, openness at 5 and 10 m, canopy roughness, leaf area index (LAI) and leaf area height volume (LAHV) for 20 sites across South-East Amazonia (ranging from 375 to 1200 ha). Compared to unburned forests, burned forests had reductions in canopy height, LAI, and LAHV, and increases in openness and roughness. These effects were more pronounced in early successional (ES) than later successional (LS) stages, for example, mean canopy height decreased 33% in ES and 14% in LS and LAI decreased 36% in ES and 18% in LS. Forests in ES stages were less resistant to fire, but more resilient (capable of recovering from a disturbance) in their post-fire regrowth than LS stage forests. Data extrapolation from our models suggests that canopy structure partially recovers with time since fire for six out of seven canopy metrics; however, LAI and LAHV in LS forests may never fully recover. Our results indicate that successional stage-specific management and policies that mitigate against fire in early secondary forests should be implemented to increase the success of forest regeneration. Mitigation of fires is critical if secondary forests are to continue to provide their wide array of ecological services. Florestas secund & aacute;rias na Amaz & ocirc;nia s & atilde;o essenciais para captura de carbono, biodiversidade e conex & atilde;o entre fragmentos florestais. Por & eacute;m, seu crescimento & eacute; altamente amea & ccedil;ado pelo fogo. Usando varredura a laser aerotransportada (ALS), entre os anos de 2016 e 2018, analisamos m & eacute;tricas de dossel em florestas secund & aacute;rias queimadas (inc & ecirc;ndios ocorridos entre 2001 e 2018) e n & atilde;o queimadas em diferentes est & aacute;gios sucessionais e sua capacidade de recupera & ccedil;& atilde;o ap & oacute;s o fogo. Avaliamos a altura m & aacute;xima e m & eacute;dia do dossel, clareiras a 5 m e 10 m, rugosidade do dossel, & iacute;ndice de & aacute;rea foliar (LAI) e volume de altura da & aacute;rea foliar (LAHV) para 20 locais no sudeste da Amaz & ocirc;nia (variando de 375 ha a 1200 ha). Comparadas com florestas n & atilde;o queimadas, florestas queimadas tiveram redu & ccedil;& otilde;es na altura do dossel, LAI e LAHV, e aumentos nas clareiras e rugosidade. Esses efeitos foram mais pronunciados nos est & aacute;gios sucessionais iniciais (ES) do que em est & aacute;gios sucessionais mais tardios (LS), por exemplo, a altura m & eacute;dia do dossel diminuiu 33% no ES e 14% no LS e o LAI diminuiu 36% no ES e 18% no LS. Florestas no est & aacute;gio ES foram menos resistentes ao fogo, mas mais resilientes (capazes de se recuperar de uma perturba & ccedil;& atilde;o) em sua regenera & ccedil;& atilde;o p & oacute;s-fogo do que florestas no est & aacute;gio LS. A partir da extrapola & ccedil;& atilde;o de dados, nossos modelos sugerem que a estrutura do dossel se recupera parcialmente com o tempo desde o fogo para seis dos sete atributos do dossel, algumas m & eacute;tricas como LAI e LAHV em florestas LS talvez nunca se recuperem totalmente. Nossos resultados indicam que o manejo espec & iacute;fico do est & aacute;gio successional e pol & iacute;ticas que mitigam contra inc & ecirc;ndios em florestas secund & aacute;rias iniciais devem ser implementados para aumentar o sucesso da regenera & ccedil;& atilde;o florestal. A mitiga & ccedil;& atilde;o de inc & ecirc;ndios & eacute; cr & iacute;tica para que as florestas secund & aacute;rias continuem a fornecer sua ampla gama de servi & ccedil;os ecol & oacute;gicos. (AU) | |
| FAPESP's process: | 17/22269-2 - Transition to sustainability and agriculture-energy-water nexus: exploring an integrated approach with case studies in the Cerrado and Caatinga |
| Grantee: | Jean Pierre Henry Balbaud Ometto |
| Support Opportunities: | Research Program on Global Climate Change - Thematic Grants |