Pecan agroforestry systems improve soil quality by stimulating enzyme activity

PeerJ. 2022 Jan 4:10:e12663. doi: 10.7717/peerj.12663. eCollection 2022.

Abstract

Background: Forest and plantation intercropping are efficient agroforestry systems that optimize land use and promote agroforestry around the world. However, diverse agroforestry systems on the same upper-plantation differently affect the physical and chemical properties of the soil.

Methods: The treatments for this study included a single cultivation (CK) pecan control and three agroforestry systems (pecan + Paeonia suffruticosa + Hemerocallis citrina, pecan + Paeonia suffruticosa, and pecan + Paeonia lactiflora). Soil samples were categorized according to the sampling depth (0-20 cm, 20-40 cm, 40-60 cm).

Results: The results demonstrated that the bulk density (BD) of soil under the pecan agroforestry system (PPH and PPL) was reduced by 16.13% and 7.10%, respectively, and the soil moisture content (MC) and total soil porosity (TPO) increased. Improvements in the physical properties of the soil under the PPS agroforestry system were not obvious when compared with the pecan monoculture. The soil total phosphorus (TP), total nitrogen (TN), available potassium (AK), and total carbon (TC) increased significantly, while the soil urease (S-UE), alkaline phosphatase (S-AKP), and 1,4-β-N-acetylglucosamines (S-NAG) enzyme activity also increased significantly, following agroforestry. Overall, the pecan agroforestry system significantly improved the physical properties of the pecan plantation soil, enriched the soil nutrients, and increased the activity of soil enzymes related to TC, TN, and TP cycles.

Keywords: Agroforestry; Enzyme activity; Pecan; Soil nutrients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carbon / chemistry
  • Carya*
  • Forests
  • Potassium
  • Soil* / chemistry

Substances

  • Soil
  • Potassium
  • Carbon

Grants and funding

This research was supported by the Major Special Science and Technology Project of Anhui Province ( 202103b06020011 and 202103a06020007), and the Forestry Science and Technology Promotion Demonstration Project of State (2021TG 02), and Forestry Science and Technology Innovation Platform Project of State(2021-08). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.