Impact of compost and natural and synthetic water absorbents on soil hydraulic properties and vegetation indices in urban green spaces

Abedi Koupai, Jahangir; Salimi, Farid Reza; Matinzadeh, Mohammad Mahdi; Dorafshan, Mohammad Mahdi

doi:10.57647/j.ijrowa.2024.1302.18

Original Article

Impact of compost and natural and synthetic water absorbents on soil hydraulic properties and vegetation indices in urban green spaces

Authors

Abstract

Purpose: In the current study, the effects of compost, natural, and synthetic superabsorbent amendments on soil water retention curve (WRC) were assessed by applying RETC software in a laboratory trial. Moreover, the effects of the mentioned materials on vegetation growth indices of four plants in three different soil textures of urban green space were evaluated.
Method: Using the randomized complete blocks-based split-plot design, the field experiment was conducted for a two-year period. The three soil textures were combined with 4 & 6gr/kg hydrogel, as well as pumice, compost, manure, and perlite at 40 & 60 gr/kg levels.
Results: According to WRC findings, there was more efficiency associated with hydrogel in sandy loam and loam soils compared to clay soil. Moreover, increased permanent wilting point water content (q_pwp), saturated water content (q_s), as well as available water (AW) were observed. Statistical analyses indicated a considerable difference in growth indices using perlite+compost in clay soil. Compared with the control soil, a 2.4-time enhancement of AW was observed in loam soil using Pumice+ Hydrogel. A significant growth indices difference was also found for loam soil using pumice+hydrogel. According to WRC results, the highest treatment rate was attributed to compost+hydrogel in sandy loam soils, which led to a 3.3-time enhancement of AW.
Conclusion: Statistical analyses revealed that compost+hydrogel could lead to the best treatment on growth indices in sandy loam textures.