A META-ANALYSIS OF THE IMPACTS OF AGROFORESTRY ON SOIL ORGANIC CARBON STOCKS IN TEMPERATE CLIMATES

Show full item record



Permalink

http://urn.fi/URN:NBN:fi:hulib-202203041397
Title: A META-ANALYSIS OF THE IMPACTS OF AGROFORESTRY ON SOIL ORGANIC CARBON STOCKS IN TEMPERATE CLIMATES
Alternative title: META-ANALYYSI METSÄPELTOVILJELYN VAIKUTUKSISTA MAAPERÄN ORGAANISIIN HIILIVARASTOIHIN LAUHKEISSA ILMASTOISSA
Author: Freudenthal, Ines
Other contributor: Helsingin yliopisto, Maatalous-metsätieteellinen tiedekunta
University of Helsinki, Faculty of Agriculture and Forestry
Helsingfors universitet, Agrikultur- och forstvetenskapliga fakulteten
Publisher: Helsingin yliopisto
Date: 2022
Language: eng
URI: http://urn.fi/URN:NBN:fi:hulib-202203041397
http://hdl.handle.net/10138/341273
Thesis level: master's thesis
Degree program: Maataloustieteiden maisteriohjelma
Master 's Programme in Agricultural Sciences
Magisterprogrammet i lantbruksvetenskaper
Specialisation: Kasvintuotantotieteet
Plant production sciences
Växtproduktionsvetenskap
Abstract: The objective of the thesis is to review and characterize (i) typical agroforestry systems in the temperate zone, (ii) levels of soil organic carbon (SOC) in agroforestry and control plots, and (iii) identify the conditions under which agroforestry farming is most likely to enhance SOC. A meta-analysis was conducted to investigate the impact of agroforestry farming systems on SOC stocks at soil depths of 0 – 20, 0 – 40 and 0 – 100 cm. Data was collected from 15 published studies and all sites are located in temperate climates. Studies had to report at least measurements on SOC concentration or stock for an agroforestry plot and a control plot (arable land, grassland, forest). Investigated treatment variables were soil depth, agroforestry system type, soil type, tree species and age. The results have shown significantly higher SOC stocks under agroforestry in comparison to controls in all three soil depth datasets. The largest amount of SOC in agroforestry was found in the first 20 cm of topsoil and at a soil depth of 60 – 100 cm. There were no significant differences found between alley cropping, silvopasture and shelterbelt systems. The most popular tree species in temperate agroforestry were Populus spp., M.domestica, Juglans regia and Picea. But no significant differences in C sequestration could be observed between tree species across all datasets. The assumption that systems with older trees have higher stocks of SOC could not be confirmed. Most common soil types of temperate agroforestry systems were Luvisol, Fluvisol and Chernozem. The meta-analysis did not verify results of other studies, which have shown that clay contents in the soil promote C sequestration. The wide variability and diversity of agroforestry systems has shown to be problematic in conducting a meta-analysis, indicated by a high heterogeneity. Furthermore, different types of study designs, lack of standardized sampling procedures and explanatory variables may have influenced the results. However, the study showed that agroforestry can be a promising carbon dioxide (CO2) mitigation option, also for the temperate climate zone.
Subject: temperate agroforestry
soil organic carbon
carbon sequestration
SOC


Files in this item

Files Size Format View

There are no files associated with this item.

This item appears in the following Collection(s)

Show full item record