Gas exchange of four woody species under salinity and soil waterlogging

Alan D Lima,Claudivan F De Lacerda,Carlos H C Sousa,Antônia L R Neves,Evandro N Silva,Marlos A Bezerra

doi:10.1590/1807-1929/agriambi.v21n10p670-674

Abstract

ABSTRACT The objective of this study was to evaluate gas exchanges in seedlings of forest species grown in saline soils and subjected to soil waterlogging cycles. The experimental design was completely randomized in a factorial arrangement, with four forest species: Myracrodruon urundeuva Fr Allemão, Mimosa caesalpiniifolia Benth, Tabebuia impetiginosa (Mart. ex. DC.) Standl and Azadirachta indica A. Juss, two soil salinity levels (1.2 and 8.6 dS m-1) and two water regimes (with and without waterlogging). Measurements of stomatal conductance, transpiration and CO2 assimilation rate were performed before and after each waterlogging period. The interaction of the highest saline level (8.6 dS m-1) and waterlogging caused greater reductions in leaf gas exchange, except for Mimosa caesalpiniifolia Benth. Tabebuia impetiginosa (Mart. ex. DC.) Standl was the species with highest sensitivity to both studied factors of stress.

Highlights

Extensive irrigated areas worldwide have shown reduction in production due to the excess of salts (Leal et al, 2008)
This study aimed to evaluate gas exchanges in seedlings of four forest species cultivated in saline soils and under soil waterlogging cycles
Forest species were used in the experiment, three of which are native to the Caatinga: ‘Aroeira’ (Myracrodruon urundeuva Fr Allemão), ‘Sabiá’ (Mimosa caesalpiniifolia Benth) and ‘Ipê roxo’

Summary

Introduction

Extensive irrigated areas worldwide have shown reduction in production due to the excess of salts (Leal et al, 2008). It is estimated that 20% of irrigated areas are affected by salinization, resulting from the accumulation of salts caused by irrigation (Aragüés et al, 2011) This advancement in irrigation with the use of low-quality water in semi-arid regions and in marginal land areas has increased the accumulation of salts in the soils and, their degradation (Ribeiro et al, 2016). Another factor that contributes to the increase of salinity is the excess of water, caused by inadequate irrigation management. Waterlogging periods in which the water depth covers the soil at higher levels can cause death of the seedlings and produce differences in their structure and density (Soares & Oliveira, 2009)

Objectives

Methods

Results