Arid Zone Research ›› 2024, Vol. 41 ›› Issue (2): 326-338.doi: 10.13866/j.azr.2024.02.15

• Agricultural Ecology • Previous Articles     Next Articles

Effects of biochar application on soil hydrothermal salinity and cotton growth in brackish water drip irrigation cotton field

LAI Hongyu(), LYU Desheng(), ZHU Yan, WANG Zhenhua, WEN Yue, SONG Libing, QI Hao   

  1. College of Water Conservancy & Architectural Engineering, Key Laboratory of Modern Water-Saving Irrigation of Xinjiang Production & Construction Group, Key Laboratory of Northwest Oasis Water-Saving Agriculture, Ministry of Agriculture and Rural Affairs, Shihezi 832000, Xinjiang, China
  • Received:2023-05-07 Revised:2023-11-21 Online:2024-02-15 Published:2024-03-11

Abstract:

To address the challenges of fresh water shortage and soil quality decline in northern Xinjiang, a field experiment was conducted, investigating the effects of different irrigation water salinity levels and biochar application on the soil hydrothermal conditions, soil salinity, and cotton growth in cotton fields. Four biochar application levels (B0: 0 t·hm-2, B1: 20 t·hm-2, B2: 40 t·hm-2, B3: 60 t·hm-2) and three irrigation water salinity levels (S1: 1 g·L-1, S2: 3 g·L-1, S3: 5 g·L-1) were established. A two-factor completely randomized combination test was used to analyze the effects of these treatments on soil water and salt temperature distribution, cotton growth index, dry matter accumulation, yield, and water use efficiency. The findings indicated that increased biochar and irrigation water salinity levels raised soil water and salt content. Higher biochar application increased the average soil temperature, while irrigation water salinity notably influenced the average soil temperature (P < 0.01). B2S2 treatment increased the cotton plant height, leaf area index, and aboveground dry matter. Optimal yield and water use efficiency occurred in the B2S2 treatment. In contrast, the B0S3 treatment displayed the lowest values, 18.50% and 26.87% lower in yield and water use efficiency, respectively, compared to the B2S2 treatment. A multiple regression equation, combined with normalization and spatial analysis, was established. The optimal biochar amount and irrigation water salinity range based on cotton yield and water use efficiency were 26-46 t·hm-2 and 2.45-3.04 g·L-1, respectively.

Key words: the amount of biochar applied, brackish water salinity, cotton growth, yield, multivariate regression analysis