Fertilizer Application

Agroecosystems make up a significant portion of terrestrial ecosystems and receive a disproportionally high amount of terrestrial nitrogen inputs from fertilizer, leading to nitrogen loss and associated environmental problems. Integrated crop livestock systems, such as pasture-integrated crop rotations, may be more environmentally sustainable however the long-term effects of this management practice on soil microorganisms and nitrogen transformations are not well understood.
Humans, through agricultural fertilizer application, inject more reactive nitrogen (Nr) to terrestrial ecosystems than do natural sources. Ammonia volatilization is a major pathway of agricultural Nr loss. Using a process-based dynamic model, Shen et al. show that ammonia volatilization from agricultural land in the US will increase by up to 81% by the end of this century due to climate change alone, posing threats to food security, air quality, and ecosystem health, but mitigation strategies are available.
The artificial drainage of heavy textured gley soils is prevalent on pasture. Drainage of a soil profile reduces the water filled pore space (WFPS) in the upper soil horizons with consequences for N2 and N2O emissions, the fate of nitrogen (N), transformational processes and microbial and bacterial communities. The present intact soil column study with isotopically enriched fertiliser investigates all these aspects simultaneously under two WFPS treatments (80% (HS) and 55% (LS) saturation).
Elsevier, Science of the Total Environment, Volume 648, 15 January 2019
One of the key Sustainable Development Goals (SDG) set by the United Nations (UN) aims by 2030 to “end hunger, achieve food security and improved nutrition and promote sustainable agriculture”. Fertilizers will play a pivotal role in achieving that goal given that ~90% of crop production growth is expected to come from higher yields and increased cropping intensity. However, materials-science research on fertilizers has received little attention, especially in Africa.
Although the effects of nitrogen (N) fertilization on soil microflora have been well studied, the effects should be verified across soil types and N-added levels. To understand the impacts of N fertilization on shifts in soil biological traits and bacterial communities and to further explore the coupling mediation of these parameters with respect to crop yields, we sampled soils from three experimental sites (each site received three levels of N fertilization (0, 168 and 312 kg N ha−1)) that share the same climatic conditions but have different soil types (clay, alluvial and sandy soils).
Elsevier, Current Opinion in Environmental Sustainability, Volume 34, October 2018
Actions on climate change (SDG 13), including in the food system, are crucial. SDG 13 needs to align with the Paris Agreement, given that UNFCCC negotiations set the framework for climate change actions. Food system actions can have synergies and trade-offs, as illustrated by the case for nitrogen fertiliser. SDG 13 actions that reduce emissions can have positive impacts on other SDGs (e.g. 3, 6, 12, 14, 15); but such actions should not undermine the adaptation goals of SDG 13 and SDGs 1, 2, 5 and 10.