Relationship between riparian plant diversity and soil factors in the middle and lower reaches of the Yellow River

Abstract

Abstract [Objective] The relationship between species diversity and soil factors in riparian zone is important to maintain the stability of riparian ecosystems. The purpose of the study is to reveal the relationship between species diversity and soil factors in riparian zone and provide references and theoretical guidance for the ecological restoration, protection, and high-quality development of the middle and lower reaches of the Yellow River. [Methods] The study examined the relationship between plant distribution, species diversity, and soil factors in the transition zone of the middle and lower reaches of the Yellow River in He􀆳nan Province by means of quadrat survey, experimental analysis, and CCA ranking. [Results] (1) Soil organic matter, available potassium, and available phosphorus in the transition zone of the middle and lower reaches of the Yellow River were moderate variability, water content, the coefficient of total nitrogen was strong variability, and the spatial distribution of soil nutrients was uneven. (2) There was a significant negative correlation between the dominance index of riparian plants and soil total nitrogen (P < 0.05). Soil pH, available potassium, and available phosphorus had no obvious effects on species richness index. The evenness index, Shannon-Wiener index, and six soil factors did not reach a significant level. (3) The distribution of Polygonum polygonatum , Cyperus capitatum , Echinochloa crusgalli, Echinochloa cristatum , and Eclipta prostrata communities was affected by water content. The distribution of Artemisia annua, Ziziphus jujuba, and Populus tomentosa was mainly affected by total nitrogen, which were mainly distributed in areas with high total nitrogen content. Humulus scandens and Amaranthus retroflexus were affected by available potassium. However, Cynodon dactylon, Xanthium strumarium , Phragmites australis, Setaria viridis, Polygonum persicaria, Vigna radiata, and other communities were less affected by soil factors. [Conclusion] The soil moisture content, available potassium, and total nitrogen in the transitional zone of the middle and lower reaches of the Yellow River are the main factors affecting plant distribution. Different plants have different requirements for soil conditions, which can reflect the relationship between vegetation and soil environment.

Keywords

• middle and lower reaches of the yellow river
• riparian zone
• plant community
• species diversity
• soil factor