The Effects of Mesquite (Prosopis juliflora) on Soils and Plant Communities in the Deserted Rangelands of Bahrain

Manal A M Sadeq,Ahmed A Salih,Jameel A Alkhuzai,Mohammed S Abido

doi:10.1155/2020/8810765

Abstract

The influence of mesquite trees (Prosopis juliflora (Swartz) D.C.) on the physicochemical properties of soils and annual understory plants was investigated in the deserted rangelands of Bahrain. Soil properties were measured in the understory and the uncanopied adjacent areas of mesquite trees. Likewise, the number of plant species was assessed in four 1 × 1 m randomly distributed quadrates in the understory and the uncanopied adjacent areas. The results showed that sand particles exceed 96% of soil composition. Soil bulk density at the 0–5 cm soil depth was significantly higher in the understory of trees compared to the uncanopied adjacent areas. However, moisture at a depth of 40–60 cm was significantly higher in the uncanopied adjacent areas. No differences in the pH, EC, K, Na, and Ca were found between understory and the uncanopied areas in all soil depths. Levels of N, P, Mg, and organic matter were significantly higher in the understory of trees compared to the uncanopied adjacent areas. Organic matter was twice the amount in the upper 20 cm of soil layers in the understory of mesquite trees. Species richness did not differ between the understory and the uncanopied areas. Nevertheless, the density of ephemerals in the understory of mesquite trees was higher than the uncanopied areas by 18%. The Shannon-Weaver index of diversity was higher in the uncanopied areas compared to the understory. The study concluded that the canopy effects of mesquite trees on soil vary with depth. Nonetheless, the influence of mesquite on flora could be beneficial for annual understory plants but subject to many operating factors, including density and cover of mesquite trees.

Highlights

Worldwide, invasive alien species are considered as direct drivers of ecological change and biodiversity decline [1, 2].ese species cause damage to the environment and human health. ey function as agents of change that influence other species, habitats, and ecosystems [3]
Annual species were measured in a four quadrate of 1 × 1 m established under the understory and the uncanopied areas of four randomly selected mesquite trees
Soil Physicochemical Properties. e results of the study indicated that sand comprised 96.4% of soil composition, while clay and silt constituted 3.4% and 0.2%, respectively

Summary

Introduction

Invasive alien species are considered as direct drivers of ecological change and biodiversity decline [1, 2]. Several authors studied the influence of mesquite trees on soil properties [9,10,11,12] Such an effect was linked to other relevant factors, including climate, soil properties, canopy density, and plant coverage [13]. Adverse effects of mesquite on biodiversity and ecosystems including rangelands, pastures, wetlands, and native flora have been controversial [4, 18,19,20,21]. E objective of this study is to determine the influence of P. juliflora on soil properties and annual understory plants in the sandy ecosystems of Bahrain. Annual species were measured in a four quadrate of 1 × 1 m established under the understory and the uncanopied areas of four randomly selected mesquite trees. Shannon-Wiener index of annual species biodiversity (H′) was calculated [33]

Materials and Methods

Results and Discussion

Disclosure