Changes in rainfall partitioning caused by the replacement of native dry forests of Lithraea molleoides by exotic plantations of Pinus elliottii in the dry Chaco mountain forests, central Argentina  

作　　者：Samia S CORTÉS Juan I WHITWORTH-HULSE Eduardo L PIOVANO Diego E GURVICH Patricio N MAGLIANO 

机构地区：[1]Land Science Research Center(CICTERRA-CONICET)and National University of Córdoba,Av.Vélez Sarsfield 1611,X5016GCA Córdoba,Argentina [2]Multidisciplinary Institute of Plant Biology,National University of Córdoba and CONICET,CC 495,X5000JJC Córdoba,Argentina [3]Environmental Study Group,Institute of Applied Maths of San Luis,National University of San Luis and CONICET,Ejército de los Andes 950,D5700HHW San Luis,Argentina [4]Department of Biology,Faculty of Chemistry,Biochemistry and Pharmacy,National University of San Luis,Ejército de los Andes 950,D5700HHW San Luis,Argentina

出　　处：《Journal of Arid Land》2020年第5期717-729,共13页干旱区科学（英文版）

基　　金：the Secretary of Science and Technology of the National University of Córdoba(2014–2017);supported by a PhD grant from the National Research Council Scientific and Technical(Dr.Samia CORTÉS).

摘　　要：The replacement of native dry forests by commercial(exotic)tree plantations could generate changes in rainfall partitioning,which further affects the water cycle.In this study,we determined(i)the rainfall partitioning into interception,throughfall and stemflow,(ii)the role of rainfall event size on rainfall partitioning,(iii)the pH of water channelized as throughfall and stemflow,and(iv)the runoff in Lithraea molleoides(a native species)and Pinus elliottii(an exotic species)stands in the dry Chaco mountain forests,central Argentina.On average,interception,throughfall and stemflow accounted for 19.3%,79.5%and 1.2%of the gross rainfall in L.molleoides stand,and 32.6%,66.7%and 0.7%of the gross rainfall in P.elliottii stand,respectively.Amounts of interception,throughfall and stemflow presented positive linear relationships with the increment of rainfall event size for both tree species(P<0.01 in all cases).Percentages of interception,throughfall and stemflow were all related to the increment of rainfall event size,showing different patterns.With increasing rainfall event size,interception exponentially decreased,throughfall asymptotically increased and stemflow linearly increased.Both P.elliottii and L.molleoides stands presented significant differences in the pH values of water channelized as throughfall(6.3 vs.6.7,respectively;P<0.01)and stemflow(4.5 vs.5.8,respectively;P<0.01).Runoff occupied only 0.3%of the gross rainfall in P.elliottii stand and was zero in L.molleoides stand.Our results showed that the native species L.molleoides presented 13.6%more water reaching the topsoil(i.e.,net rainfall;net rainfall=gross rainfall-interception-runoff)than the exotic species P.elliottii.This study improves our understanding of the effects of native vegetation replacement on the local water balance in the dry forest ecosystems.

关 键 词：DRYLANDS ECOHYDROLOGY land use changes spatial heterogeneity water-limited environments 

分 类 号：S718.5[农业科学—林学]