Forest change is a major environmental problem worldwide. Forest streams, with their large aquatic-terrestrial interface and strong dependence on terrestrially derived organic matter, are highly sensitive to forest changes. Fast-wood plantations can be particularly threatening if they markedly differ from native forests. Eucalyptus plantations, in particular, cover large areas worldwide (>20 million ha, mostly from 35 degrees S to 35 degrees N), but their effects on stream functioning have been addressed mostly in the Iberian Peninsula, which limits generalization to other regions. We assessed the effect of eucalyptus plantations on total (microbial decomposers and macroinvertebrates; in coarse mesh bags) and microbial-driven (in fine mesh bags) leaf litter decomposition by comparing streams flowing through native forests and eucalyptus plantations in seven regions in the Iberian Peninsula, Central Africa and South America. We found an overall significant inhibition of total litter decomposition by 23%. The effect did not significantly differ across regions, although a significant inhibition was found for Spain (-41%), South Brazil (-31%) and Uruguay (-36%) (Portugal had a marginally nonsignificant inhibition by 50%) but not for other regions, suggesting that the effects of plantations in temperate climates are mediated through effects on macroinvertebrate communities. Contrarily, the overall effect for microbial-driven litter decomposition was non-significant, but it significantly differed across regions with a significant stimulation in Central Brazil (110%) and Uruguay (32%), and nonsignificant effects for other regions (Kenya had a marginally nonsignificant inhibition by 48%), suggesting that functional redundancy among microbial communities is not general and effects can occur if plantations induce changes in nutrient availability, solar irradiation or litter characteristics.
1.Univ Coimbra, Dept Life Sci, MARE Marine & Environm Sci Ctr, P-3004517 Coimbra, Portugal 2.Univ Basque Country UPV EHU, Dept Plant Biol & Ecol, Fac Sci & Technol, POB 644, Bilbao 48080, Spain 3.Basque Fdn Sci, Ikerbasque, Bilbao 48013, Spain 4.James Cook Univ, Coll Sci & Engn, Townsville, Qld 4811, Australia 5.Univ Republica, Grp Ecol & Rehabil Sistemas Acuat, Dept Ecol & Gest Ambiental, Ctr Univ Reg Este, Montevideo, Uruguay 6.Catholic Univ Temuco, Fac Nat Resource, Dept Environm Sci, Temuco, Chile 7.Univ Concepcion, Dept Sistemas Acuat, Fac Ciencias Ambientales, Concepcion, Chile 8.Univ Concepcion, Ctr EULA Chile, Concepcion, Chile 9.Univ Brasilia UnB, AquaRiparia, Dept Ecol, Inst Ciencias Biol, Campus Univ Darcy Ribeiro, BR-70910900 Brasilia, DF, Brazil 10.Univ Reg Integrada Alto Uruguai & Missoes, Dept Ciencias Biol, BR-99709910 Erechim, RS, Brazil 11.Egerton Univ, Dept Biol Sci, Njoro, Kenya 12.Community Univ Chapeco Reg, Program Postgrad Environm Sci, BR-89809000 Chapeco, SC, Brazil
Recommended Citation:
Ferreira, Veronica,Boyero, Luz,Calvo, Clementina,et al. A Global Assessment of the Effects of Eucalyptus Plantations on Stream Ecosystem Functioning[J]. ECOSYSTEMS,2019-01-01,22(3):629-642