• Energy Research

AbstractPastoral systems are the dominant livestock production system in arid and semiarid regions of sub‐Saharan Africa (SSA). They are often the only form of agriculture that can be practiced due to unfavorable climate and soil fertility levels that prevent crop cultivation. Pastoralism can have negative impacts on the environment, including land degradation, greenhouse gas emissions and other gases to the atmosphere, soil erosion, water pollution and biodiversity loss. Here, we review the current knowledge on nitrogen (N) cycling, storage, and loss pathways, with an emphasis on identification of N emission hotspots. Our review reports a large uncertainty in the amount of N lost as ammonia from excreta and manure storage, as well as N losses via nitrate and DON leaching. We also found that another major N loss pathway (18%), soil N2 emissions, has not yet been measured. In order to summarize the available information, we use a virtual pastoral farm, with characteristics and management practices obtained from a real farm, Kapiti Research Station in Kenya. For outlining N flows at this virtual farm, we used published data, data from global studies, satellite imagery and geographic information system (GIS) tools. Our results show that N inputs in pastoral systems are dominated by atmospheric N deposition (˜80%), while inputs due to biological nitrogen fixation seems to play a smaller role. A major N loss pathway is nitrogen leaching (nitrate > DON) from pastures (33%). Cattle enclosures (bomas), where animals are kept during night, represent N emissions hotspots, representing 16% of the total N losses from the system. N losses via ammonia volatilization and N2O were four and three orders of magnitude higher from bomas than from the pasture, respectively. Based on our results, we further identify future research requirements and highlight the urgent need for experimental data collection to quantify nitrogen losses from manure in animal congregation areas. Such information is needed to improve our understanding on N cycling in pastoral systems in semiarid regions and to provide practical recommendations for managers that can help with decision‐making on management strategies in pastoral systems in semiarid savannas.

AbstractPastoral systems are the dominant livestock production system in arid and semiarid regions of sub‐Saharan Africa (SSA). They are often the only form of agriculture that can be practiced due to unfavorable climate and soil fertility levels that prevent crop cultivation. Pastoralism can have negative impacts on the environment, including land degradation, greenhouse gas emissions and other gases to the atmosphere, soil erosion, water pollution and biodiversity loss. Here, we review the current knowledge on nitrogen (N) cycling, storage, and loss pathways, with an emphasis on identification of N emission hotspots. Our review reports a large uncertainty in the amount of N lost as ammonia from excreta and manure storage, as well as N losses via nitrate and DON leaching. We also found that another major N loss pathway (18%), soil N2 emissions, has not yet been measured. In order to summarize the available information, we use a virtual pastoral farm, with characteristics and management practices obtained from a real farm, Kapiti Research Station in Kenya. For outlining N flows at this virtual farm, we used published data, data from global studies, satellite imagery and geographic information system (GIS) tools. Our results show that N inputs in pastoral systems are dominated by atmospheric N deposition (˜80%), while inputs due to biological nitrogen fixation seems to play a smaller role. A major N loss pathway is nitrogen leaching (nitrate > DON) from pastures (33%). Cattle enclosures (bomas), where animals are kept during night, represent N emissions hotspots, representing 16% of the total N losses from the system. N losses via ammonia volatilization and N2O were four and three orders of magnitude higher from bomas than from the pasture, respectively. Based on our results, we further identify future research requirements and highlight the urgent need for experimental data collection to quantify nitrogen losses from manure in animal congregation areas. Such information is needed to improve our understanding on N cycling in pastoral systems in semiarid regions and to provide practical recommendations for managers that can help with decision‐making on management strategies in pastoral systems in semiarid savannas.

Aotearoa New Zealand's rapidly growing aerospace sector is still in its infancy, which presents us with the unique opportunity to incorporate sustainability as a key performance parameter from the outset. Through surveys and interviews with key stakeholder groups, we show that currently, the sector largely deprioritises environmental sustainability and compliance with Te Tiriti o Waitangi in favour of economic growth. Actors are not incentivised to consider any aspects of sustainability. While environmental concerns are acknowledged, they are often viewed as technical challenges to overcome by individual companies, rather than global systemic issues that require a collaborative approach. Moreover, the Government's role as a customer, investor and regulator creates a sustainability leadership vacuum, with no clear commitment to quantify or prioritise sustainability within the sector. The results highlight the need for a new approach to balance growth with genuine sustainable development principles using innovative governance models.

Aotearoa New Zealand's rapidly growing aerospace sector is still in its infancy, which presents us with the unique opportunity to incorporate sustainability as a key performance parameter from the outset. Through surveys and interviews with key stakeholder groups, we show that currently, the sector largely deprioritises environmental sustainability and compliance with Te Tiriti o Waitangi in favour of economic growth. Actors are not incentivised to consider any aspects of sustainability. While environmental concerns are acknowledged, they are often viewed as technical challenges to overcome by individual companies, rather than global systemic issues that require a collaborative approach. Moreover, the Government's role as a customer, investor and regulator creates a sustainability leadership vacuum, with no clear commitment to quantify or prioritise sustainability within the sector. The results highlight the need for a new approach to balance growth with genuine sustainable development principles using innovative governance models.