General context

Conservation agriculture (CA)’s applicability in different farming contexts is debated where farmers tend to implement some CA principles or their different combinations. This study examined the effectiveness of different combinations of CA principles in mitigating climate change and improving maize yields (sustainable agriculture intensification [SAI]). It was hypothesised that; the full combination of CA principles is a better placed option for SAI through reduced greenhouse gas emissions and increased soil organic carbon sequestration. A component omission experiment of CA principles was established in 2013. Results show the overarching role of mulching under no-tillage as a better option in SAI.

Research question

How does the combination of different CA principles impact greenhouse gas emissions, soil organic carbon stocks, and their potential to reduce global warming in low-nitrogen input cropping systems in sub-humid Zimbabwe?

Importance of the research question

The research question is of significant importance for several reasons:

  i.      Climate change mitigation

Understanding the impact of different combinations of CA principles on GHG emissions is crucial for developing effective strategies to mitigate climate change. This research question addresses the specific context of low-nitrogen input cropping systems, which is characteristic of smallholder farming communities in the developing world, providing insights into sustainable agricultural intensification.

 ii.      Crop productivity and food security

The research question explores the relationship between CA principles and crop yields. By investigating the effectiveness of different combinations of CA principles, the study provides valuable information on how these practices can improve crop productivity. This knowledge is essential for promoting food security in regions with sub-humid climates, such as Zimbabwe.

iii.      Soil health and carbon sequestration

The research question also focuses on SOC stocks, which are essential for maintaining soil health and fertility. Understanding how different CA principles influence SOC stocks at varying soil depths provides insights into the potential for carbon sequestration in such cropping systems. This information can inform land management practices aimed at enhancing soil quality, nutrient cycling, and long-term sustainability.

iv.      Context-specific applicability

The research question acknowledges the variability in farming contexts and debates surrounding the applicability of CA principles. By conducting the study in sub-humid Zimbabwe and considering different soil types, it addresses the need for region-specific knowledge and insights into the effectiveness of CA practices in diverse agricultural settings. This context-specific approach enhances the relevance and practicality of the research findings.

Overall, this research question contributes to the broader fields of climate change mitigation, sustainable agriculture, soil health, and food security. The findings can inform policymakers, farmers, and researchers in making informed decisions and developing strategies to promote environmentally friendly and productive agricultural practices in sub-humid regions like Zimbabwe.

Brief biography

Whilst pursuing a DPhil in Agroecology and Climate change mitigation, Shumba is a holder of an MPhil in Integrated Soil Fertility Management and BSc Honours in Agriculture (Soil Science). He is an agriculture research scientist with experience in agroecology studies with sound greenhouse gas sampling and data processing skills.He is also a comfortable research collaborator who can work with people of all levels and from diverse backgrounds. His career objective is to take up new and more challenging national and international researches in the quest to develop sustainable agriculture innovations.  

Experience and achievements

Shumba has gained hands-on experience in static chamber fabrication for greenhouse gas sampling. He was also exposed to collaborative research and networking. Field data collection, statistical analysis, graphics, and data synthesis into publishable manuscripts are some of the key attributes that were imparted to me.

He has managed to publish two papers in high-impact journals as well as an online article published by The Conversation.