Sieg has been a member of the American Society of Agronomy and Soil Science Society of America since 1983, was elected a fellow in 2010, awarded the International Service Award in 2015, and Fulbright Fellowships in 2009 and 2016. She has published two books, 128 journal articles and dozens of extension bulletins as well as an innovative learning lab website for sustainable land management and food security in Africa. She provided soil fertilizer recommendation advice that has informed fertilizer formulations for voucher programs throughout East Africa, and is a pioneer in participatory action research and extension approaches that support co-generation of knowledge that is relevant for smallholders. Her highly collaborative approach to sustainable systems science has helped bring to the world’s attention the inadvertent negative consequences, tradeoffs and synergies of sole versus diversified cropping, and the urgent need for biologically sound soil and crop management. Open science through meta-analysis, citizen science and handheld soil/plant monitoring is a current focus, for evidence based agronomy that improves decision making. Soil fertility related research in Africa:
1. Develop and scale out fertilizer recommendations for smallholder rainfed maize systems. The last two decades have seen numerous field trials and soil monitoring exercises in Africa to quantify crop response to fertilizers, yet there are few successful efforts. My research has shown that nitrogen is the primary driver of cereal yields, and improvements in soil health, organic C and good agronomy (weed control and timing) are required to improve fertilizer efficiency, leading to the urgent need for extension recommendations to be delivered to farmers through a targeted, season-long mobile campaign that tailors recommendations to local conditions and weather. This is a response farming recommendation approach: a basal NP fertilizer is applied with timely weeding, and the local rainfall pattern and soil conditions dictate recommendations on multiple split nitrogen fertilizer applications. By comparing farmers who receive general advice with targeted advice we will test if nitrogen targeted response is a breakthrough approach, and if tailored agronomic recommendations can be scaled through mobile voice and text advice.
2. I lead a ten year sustainable intensification of agriculture project in Malawi through a contract with IITA on the ‘Africa RISING’ project funded by USAID and a four year SIIL project in Tanzania on ‘Raising crop yields in maize and bean systems through bidirectional learning and SI’. Soil health and environmental monitoring at multiple scales, linked to socio-economic data, is our unique approach to understand drivers of crop and soil management.
3. Through participatory research and geovisualization of spatial and temporal ‘niches’ for crop diversification I have worked with transdisciplinary teams to 1) document poor productivity of sole-maize and lack of response to fertilizers and 2) supported adoption by over 10,000 farm families of multipurpose legume crop diversification of maize, such as the pigeonpea-groundnut doubled up legume technology. Recent evidence is consistent with widespread adoption of doubled up legumes into neighboring countries and this technology is now officially approved by the Malawi government, Technology Release Committee.← Back to Blog