Assessing the Impact of Soil Health Refurbishment Practices on Carbon Sequestration and Crop Yield in Urbanized Agricultural Soils.

Project Abstract

This study evaluates how soil health refurbishment practices influence carbon sequestration and crop yield in urbanized agricultural soils, addressing the dual challenges of climate change and food security in peri-urban environments. The research integrates field experiments, laboratory analyses, and modeling to quantify the effectiveness of combined soil management interventions—organic matter amendment, biochar incorporation, reduced tillage, cover cropping, and targeted microbial inoculants—on soil organic carbon (SOC) stocks, aggregate stability, nutrient cycling, moisture retention, and microbial diversity over two production cycles. A multi-site design across three distinct urban-adjacent agroecosystems captures variability in soil texture, baseline fertility, pollution exposure, and microclimatic conditions, enabling robust inference and scalability. The study employs a split-plot experimental layout with randomized complete blocks to test single and synergistic treatments, complemented by a longitudinal monitoring framework that tracks SOC dynamics using 13C/14C isotopic tracing, soil respiration, and bulk density measurements. Crop response is assessed through yield quantity and quality metrics, including carbohydrate and protein content for staple crops, micronutrient profiling, and harvest index, alongside phenological observations to detect shifts in growth stages under different soil refurbishment regimes. Soil health indicators such as pH, cation exchange capacity, microbial biomass carbon, enzyme activities (dehydrogenase, phosphatase, urease), and litter decomposition rates are measured to elucidate mechanistic pathways linking management practices to soil function and plant performance. Additionally, the research evaluates greenhouse gas fluxes (CO2, N2O, CH4) to determine the net climate impact of refurbishment strategies, factoring in potential trade-offs associated with mineralization rates and nitrogen losses. Economic and life-cycle assessments accompany agronomic results to inform feasibility for urban farmers, considering input costs, labor requirements, and long-term productivity gains. Data synthesis uses mixed-effects models and structural equation modeling to partition direct and indirect effects of soil refurbishment on carbon sequestration and yield, while spatial analysis investigates variability at microtopographic scales and the influence of urban edge effects. The study hypothesizes that integrated refurbishment regimes will enhance SOC sequestration, improve soil structure and water-holding capacity, bolster nutrient use efficiency, and thereby sustain or increase crop yield in the face of urban stressors. Findings are expected to reveal that multi-pronged approaches yield synergistic benefits greater than single-practice implementations, with differential responses across soil types and pollution gradients. The research contributes to the development of evidence-based guidelines for urban agriculture that optimize soil health restoration while maximizing carbon sequestration and food production, offering scalable strategies for policymakers, extension services, and practitioners to promote resilient, low-emission urban food systems.

Project Overview

What This Project Is About

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A plain-language overview of how soil health practices can influence carbon storage in the soil and crop yields in urbanized farming areas, and what the student will explore and measure. The project looks at simple changes like soil amendments, cover crops, and reduced disturbance to see how they affect soil carbon and plant yield over a growing season. It explains why healthy soil matters for climate and food production in cities surrounded by farming land.

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The Problem It Addresses

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Soil quality in urban and peri-urban farms is often degraded by compacting, limited organic matter, and poor management, which can lower crop yield and soil carbon storage. There is a need to test practical, affordable refurbishments that improve soil health, boost yields, and contribute to climate goals in real-world urban farm settings. The project fills this gap by comparing common practices in a straightforward, local context.

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Objectives of the Project

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1. Identify which soil health practices most improve carbon storage and crop yield in urban soils.
2. Measure changes in soil organic matter, moisture, and microbial activity.
3. Evaluate crop yield responses to different refurbishment methods.
4. Provide practical guidelines for urban farmers on cost and effectiveness.

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What You Will Do Step by Step

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1. Review simple literature on soil health and carbon in urban soils.
2. Choose a small set of refurbishments (e.g., compost addition, cover crops, reduced tillage).
3. Design a basic field trial with plots representing each practice.
4. Collect soil samples and measure organic matter and moisture at key times.
5. Record crop growth and final yield for each plot.
6. Analyze data with easy comparison methods (mean differences, basic charts).
7. Prepare a short report with practical farming tips.

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Expected Outcome

A clear set of findings showing which soil health refurbishments most improve carbon storage and yield, plus simple guidelines for urban farmers to adopt effective practices.