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Aceleración global de las tasas de cambio de la vegetación en los últimos 18.000 años
Ondřej Mottl1, Suzette G A Flantua1,2, Kuber P Bhatta3
1Department of Biological Sciences, University of Bergen, N-5020 Bergen, Norway. ondrej.mottl@gmail.com s.g.a.flantua@gmail.com.
Science (New York, N.Y.)
|May 21, 2021
Resumen
Las actividades humanas han acelerado el cambio de la vegetación global a un ritmo sin precedentes en los últimos ~ 4.600 años. Esta transformación de los ecosistemas terrestres impulsada por el hombre ahora rivaliza o supera los cambios climáticos del pasado.
Área de la Ciencia:
- Paleoecología
- Ciencia del cambio climático
- Dinámica de los ecosistemas
Sus antecedentes:
- La vegetación global ha sufrido transformaciones significativas debido a cambios climáticos pasados y presiones humanas recientes.
- Comprender los patrones globales y la magnitud de las tasas de cambio de la vegetación sigue siendo un desafío.
Objetivo del estudio:
- Investigar las tasas de cambio de composición de la vegetación a nivel mundial en los últimos 18.000 años.
- Para comparar el cambio de vegetación impulsado por el hombre con los cambios impulsados por el clima durante la deglaciación.
Principales métodos:
- Utilizó una compilación de 1181 secuencias de polen fósil.
- Aplicó métodos estadísticos recientemente desarrollados para analizar las tasas de cambio de la vegetación.
Principales resultados:
- Detectó una aceleración mundial en las tasas de cambio de composición de la vegetación desde hace entre 4.6 y 2.9 mil años.
- Se observó que las tasas de cambio del Holoceno tardío no tienen precedentes a nivel mundial en cuanto a magnitud y extensión en los últimos 18.000 años.
- Encontró que las tasas de cambio en todos los continentes durante el Holoceno Tardío iguales o superiores a las tasas deglaciales.
Conclusiones:
- La escala de los impactos humanos en los ecosistemas terrestres es comparable o mayor que las transformaciones impulsadas por el clima de la última deglaciación.
- La aceleración del cambio de biodiversidad observada en datos ecológicos recientes comenzó hace milenios debido a las presiones humanas.
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