The Threats to Food Security

Author(s):  
Gordon Conway ◽  
Ousmane Badiane ◽  
Katrin Glatzel

This chapter explores threats to food security. It reveals many challenges arising from a range of threats external to the farm household, including severe biological threats from pests, disease, and weeds. Moreover, healthy, fertile soils are the cornerstone of food security and rural livelihoods, but African soils are degrading. Water is just as important for the productivity of plants, and lack of water leads to chronic and acute stress. Indeed, Africa is already battling the impacts of climate change. Rising temperatures and variable rainfall are increasing the exposure of smallholders to drought, famine, and disease. Agriculture is an important emitter of greenhouse gases (GHGs), not only carbon dioxide but also such powerful gases as methane and nitrous oxide. In addition, there are often severe socioeconomic challenges, including unstable and high prices of basic commodities. Finally, conflicts cause disruption to food security.

2018 ◽  
Vol 25 (3) ◽  
pp. 383-394 ◽  
Author(s):  
Marta Marszałek ◽  
Zygmunt Kowalski ◽  
Agnieszka Makara

Abstract Pig slurry is classified as a natural liquid fertilizer, which is a heterogeneous mixture of urine, faeces, remnants of feed and technological water, used to remove excrement and maintain the hygiene of livestock housing. The storage and distribution of pig slurry on farmland affect the environment as they are associated with, among others, the emission of various types of gaseous pollutants, mainly CH4, CO2, N2O, NH3, H2S, and other odorants. Methane (CH4), carbon dioxide (CO2) and nitrous oxide (N2O) are greenhouse gases (GHGs) which contribute to climate change by increasing the greenhouse effect. Ammonia (NH3) and hydrogen sulfide (H2S) are malodorous gases responsible for the occurrence of odour nuisance which, due to their toxicity, may endanger the health and lives of humans and animals. NH3 also influences the increase of atmosphere and soil acidification. The article presents the environmental impact of greenhouse gases and odorous compounds emitted from pig slurry. Key gaseous atmospheric pollutants such as NH3, H2S, CH4, CO2 and N2O have been characterized. Furthermore, methods to reduce the emission of odours and GHGs from pig slurry during its storage and agricultural usage have been discussed.


Author(s):  
Evangeline Fisher

Plant communities in the high Arctic are distributed according to moisture gradients. If moisture regimes change in response to future climate change, the distribution of plant communities is also likely to change. An understanding of how interactions between vegetation community type and changes in temperature and moisture levels will impact the flux of nitrous oxide, methane and carbon dioxide in arctic soils is critical for predicting potential positive feedback to climate warming. My research quantifies the flux of these greenhouse gases from mineral soils collected from three different plant community types at Cape Bounty, Nunavut: wet sedge, mesic heath, and polar desert. Intact soil cores (0‐10 cm) were collected during July of 2008, then sealed and refrigerated for transportation back to Kingston. The cores were incubated at 4°C, 8°C, and 12°C, including a three week pre‐incubation to ensure the cores were completely equilibrated to their respective temperature. My results suggest a significant temperature dependency for production of each of the greenhouse gases, with enhanced output in the characteristically wetter sites. The response to temperature (Q10) does not; however, appear to be consistent across the different plant communities. Further field studies were conducted to determine the impact of these vegetative community types on observed soil temperature. My results demonstrate a tendency toward warmer temperatures and enhanced diurnal fluctuations at drier sites. These initial results suggest that in a warmer climate, high Arctic soils have the potential to contribute to a positive feedback to climate change through the efflux of these gases.29


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Angela Margaret Evans

Abstract Background Healthcare aims to promote good health and yet demonstrably contributes to climate change, which is purported to be ‘the biggest global health threat of the 21st century’. This is happening now, with healthcare as an industry representing 4.4% of global carbon dioxide emissions. Main body Climate change promotes health deficits from many angles; however, primarily it is the use of fossil fuels which increases atmospheric carbon dioxide (also nitrous oxide, and methane). These greenhouse gases prevent the earth from cooling, resulting in the higher temperatures and rising sea levels, which then cause ‘wild weather’ patterns, including floods, storms, and droughts. Particular vulnerability is afforded to those already health compromised (older people, pregnant women, children, wider health co-morbidities) as well as populations closer to equatorial zones, which encompasses many low-and-middle-income-countries. The paradox here, is that poorer nations by spending less on healthcare, have lower carbon emissions from health-related activity, and yet will suffer most from global warming effects, with scant resources to off-set the increasing health care needs. Global recognition has forged the Paris agreement, the United Nations sustainable developments goals, and the World Health Organisation climate change action plan. It is agreed that most healthcare impact comes from consumption of energy and resources, and the production of greenhouse gases into the environment. Many professional associations of medicine and allied health professionals are advocating for their members to lead on environmental sustainability; the Australian Podiatry Association is incorporating climate change into its strategic direction. Conclusion Podiatrists, as allied health professionals, have wide community engagement, and hence, can model positive environmental practices, which may be effective in changing wider community behaviours, as occurred last century when doctors stopped smoking. As foot health consumers, our patients are increasingly likely to expect more sustainable practices and products, including ‘green footwear’ options. Green Podiatry, as a part of sustainable healthcare, directs us to be responsible energy and product consumers, and reduce our workplace emissions.


2007 ◽  
Vol 8 ◽  
pp. 1-7
Author(s):  
Krishna B. Karki

Concentration of greenhouse gases has been found increasing over the past centuries. Carbon dioxide (9-26% greenhouse effect), methane (4-9%), and nitrous oxide (3-6%) are the three principal greenhouse gasses though chloroflourocarbon and halon are also included as greenhouse gasses but are in very small greenhouse effect. These gasses are produced both from natural process and anthropogenic activities .Increase of these greenhouse gasses from nature in the atmosphere is mainly from the decomposition of organic matter, nitrification and denitrification of nitrogen including respiration by the plants. Anthropogenic production of carbon dioxide is from burning of fossil fuel whereas for methane livestock and paddy cultivation. Agricultural activities mainly use of mineral fertilizer is responsible for nitrous oxide emission. Increase of these gasses in atmosphere increases temperature that further accelerates evaporation of moisture from the earth’s surface. Increase in water vapor in the atmosphere will further aggravate temperature rise. This increase in atmospheric temperature has direct effect in the melting of glacier ice in Nepalese Himalaya. Melting of ice and increases water volume in the glacier fed rivers and glacier lakes. Rise in water volume beyond its capacity the glacial lakes bursts releasing millions of cubit meters of water and takes million of lives and properties downstream. If this continues there will be no more ice left in the Himalaya and in the long run all the rivers of Nepal will go dry and country will face serious water shortage for drinking, irrigation and other purposes. The Journal of AGRICULTURE AND ENVIRONMENT Vol. 8, 2007, pp. 1-7


2016 ◽  
Vol 155 (5) ◽  
pp. 703-724 ◽  
Author(s):  
A. MULUNEH ◽  
L. STROOSNIJDER ◽  
S. KEESSTRA ◽  
B. BIAZIN

SUMMARYStudies on climate impacts and related adaptation strategies are becoming increasingly important to counteract the negative impacts of climate change. In Ethiopia, climate change is likely to affect crop yields negatively and therefore food security. However, quantitative evidence is lacking about the ability of farm-level adaptation options to offset the negative impacts of climate change and to improve food security. The MarkSim Global Climate Model weather generator was used to generate projected daily rainfall and temperature data originally taken from the ECHAM5 general circulation model and ensemble mean of six models under high (A2) and low (B1) emission scenarios. The FAO AquaCrop model was validated and subsequently used to predict maize yields and explore three adaptation options: supplemental irrigation (SI), increasing plant density and changing sowing date. The maximum level of maize yield was obtained when the second level of supplemental irrigation (SI2), which is the application of irrigation water when the soil water depletion reached 75% of the total available water in the root zone, is combined with 30 000 plants/ha plant density. It was also found that SI has a marginal effect in good rainfall years but using 94–111 mm of SI can avoid total crop failure in drought years. Hence, SI is a promising option to bridge dry spells and improve food security in the Rift Valley dry lands of Ethiopia. Expected longer dry spells during the shorter rainy season (Belg) in the future are likely to further reduce maize yield. This predicted lower maize production is only partly compensated by the expected increase in CO2 concentration. However, shifting the sowing period of maize from the current Belg season (mostly April or May) to the first month of the longer rainy season (Kiremt) (June) can offset the predicted yield reduction. In general, the present study showed that climate change will occur and, without adaptation, will have negative effects. Use of SI and shifting sowing dates are viable options for adapting to the changes, stabilizing or increasing yield and therefore improving food security for the future.


2021 ◽  
Vol 3 ◽  
Author(s):  
Peter Healey ◽  
Robert Scholes ◽  
Penehuro Lefale ◽  
Pius Yanda

Climate change embeds inequities and risks reinforcing these in policies for climate change remediation. In particular, with policies designed to achieve “net zero” carbon dioxide, offsets may be considered inequitable if seen to avoid or delay gross emission reductions; offsets to emissions through technologically mature methods of carbon dioxide removals (CDR) require natural resources at scales threatening food security; knowledge of the potential of immature CDR is largely a global north monopoly; and CDR in particular environments is ill-understood and its implications for development unexamined. The use of CDR to contribute to robust progress toward Paris climate goals requires global agreement on simultaneously reducing emissions and enhancing removals, equity in burden sharing, and an interdisciplinary effort led by individual jurisdictions and focused on the co-development of technologies and governance to create CDR portfolios matched to local needs.


Earth ◽  
2022 ◽  
Vol 3 (1) ◽  
pp. 45-71
Author(s):  
Dhurba Neupane ◽  
Pramila Adhikari ◽  
Dwarika Bhattarai ◽  
Birendra Rana ◽  
Zeeshan Ahmed ◽  
...  

Climate prediction models suggest that agricultural productivity will be significantly affected in the future. The expected rise in average global temperature due to the higher release of greenhouse gases (GHGs) into the atmosphere and increased depletion of water resources with enhanced climate variability will be a serious threat to world food security. Moreover, there is an increase in the frequency and severity of long-lasting drought events over 1/3rd of the global landmass and five times increase in water demand deficits during the 21st century. The top three cereals, wheat (Triticum aestivum), maize (Zea mays), and rice (Oryza sativa), are the major and staple food crops of most people across the world. To meet the food demand of the ever-increasing population, which is expected to increase by over 9 billion by 2050, there is a dire need to increase cereal production by approximately 70%. However, we have observed a dramatic decrease in area of fertile and arable land to grow these crops. This trend is likely to increase in the future. Therefore, this review article provides an extensive review on recent and future projected area and production, the growth requirements and greenhouse gas emissions and global warming potential of the top three cereal crops, the effects of climate change on their yields, and the morphological, physiological, biochemical, and hormonal responses of plants to drought. We also discuss the potential strategies to tackle the effects of climate change and increase yields. These strategies include integrated conventional and modern molecular techniques and genomic approach, the implementation of agronomic best management (ABM) practices, and growing climate resilient cereal crops, such as millets. Millets are less resource-intensive crops and release a lower amount of greenhouse gases compared to other cereals. Therefore, millets can be the potential next-generation crops for research to explore the climate-resilient traits and use the information for the improvement of major cereals.


Author(s):  
Never Mujere

Concerns of food and environmental security have increased enormously in recent years due to the vagaries of climate change and variability. Efforts to promote food security and environmental sustainability often reinforce each other and enable farmers to adapt to and mitigate the impact of climate change and other stresses. Some of these efforts are based on appropriate technologies and practices that restore natural ecosystems and improve the resilience of farming systems, thus enhancing food security. Climate smart agriculture (CSA) principles, for example, translate into a number of locally-devised and applied practices that work simultaneously through contextualised crop-soil-water-nutrient-pest-ecosystem management at a variety of scales. The purpose of this paper is to review concisely the current state-of-the-art literature and ascertain the potential of the Pfumvudza concept to enhance household food security, climate change mitigation and adaptation as it is promoted in Zimbabwe. The study relied heavily on data from print and electronic media. Datasets pertaining to carbon, nitrous oxide and methane storage in soils and crop yield under zero tillage and conventional tillage were compiled. Findings show that, compared to conventional farming, Pfumvudza has great potential to contribute towards household food security and reducing carbon emissions if implemented following the stipulated recommendations. These include among others, adequate land preparation and timely planting and acquiring inputs. However, nitrous oxide emissions tend to increase with reduced tillage and, the use of artificial fertilizers, pesticides and herbicides is environmentally unfriendly.


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