Climate Change impacts on the Kavango–Zambezi Transfrontier Conservation Area, Africa

Filippelli Lab, Earth Sciences, IUPUI

Overview

• Climate
• Hydrology
• Agriculture
• Livestock
• Wildlife

Figure. The KAZA TFCA. Green shading indicates IUCN protected areas. ESRI.

Climate change impacts on water distribution

Climate projections - Representative Concentration Pathways (RCP)

• Based on greenhouse gas concentration

RCP 2.6: ~1.5° C peak warming

RCP 4.5: ~2.5° C

RCP 8.5: ~4.5° C

• RCP scenarios used to force various global climate models (GCMs)

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• GCMs incorporate various greenhouse gas concentration scenarios (the RCPs) into a dynamic simulation which considers the interactions between the atmosphere, land surface, ocean and sea ice.

Figure. Average surface temperature change under RCP 2.6 and RCP 8.5, respectively. European Environment Agency.

• Decrease in overall rainfall (60-120mm/yr) w/ increasing intensity of rain events
• Regional average 600-900mm/yr
• Shorter wet season, delayed onset (8-12 days)
• Potential impacts on hydroelectric power generation

• Droughts will become more severe in SSAF, however the KAZA subregion will only see minor change
• El Nino and La Nina episodes will increase in frequency (below avg and above avg precipitation)
• Short duration drought frequency will increase 4-7%
• Long duration drought frequency will increase 2-10%

Figure. Palmer Drought Severity Index (PDSI) for RCP 4.5 and RCP 8.5. Gizaw and Gan, 2016.

Figure. Median change in (a) onset, (b) cessation, (c) season length and (d) wet season rainfall based on RCP 8.5. Dunning et al., 2018.

Hydrology-Water is a key resource

Two large river basins

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1. Okavango river basin

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• Zambezi river basin

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Water used for:

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• Household
• Agriculture irrigation
• Industrial activities
• Tourism facilities

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The Okavango River Basin

• Water is used by a full range of uses and water is competing.

Projected decrease in total renewable water resources

Projected growth in consumptive water demand

• Decrease water availabilities for each country
• Increase in water demand by decades
• Most significant increases are expected in Namibia and Angola

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Recommendations to protect water and wetland in KAZA

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• Promote integrated catchment management
• Infrastructure development
• Minimize land use practices

Agriculture - Molapo Farming

• “Flood recession farming”
• Mostly conducted in the Okavango Delta region and is essential for the communities within and around
• Produces higher yields compared to dryland farming even under extreme conditions
• Low levels of precipitation, most abiotic factors, and extreme conditions don’t have a strong effect on this type of farming compared to dryland
• Many communities also do dryland farming
• Overall, the next steps would include:
• Figuring out how to stabilize this type of farming/other types as well
• How to control it
• how to divert rivers for more consistency for all agriculture

Source: https://www.researchgate.net/figure/Map-of-the-Okavango-Delta-showing-its-major-inflow-of-Okavango-River-at-Mohembo_fig1_326991642

Livestock Agriculture

Benefits

• Traditional livelihood in KAZA
• Appropriate location for raising livestock
• Potential for land regeneration and CO2 drawdown via managed grazing

Challenges

• Desertification risk and harm
• Must coexist with wildlife conservation
• Ungulate diseases e.g. foot-and-mouth disease (FMD) in wild and domestic herds
• Access and competitiveness in international market
• Competition for crop residue between livestock grazing and soil mulching
• Increased pressure on urban resources when farms fail, e.g. peri-urban Lusaka

Climate ←→ Agriculture

Huang et al., 2020

Livestock Agriculture

Solutions

• Limited expansion of livestock agriculture
• Rotational grazing: fences allow for isolating herds from disease-infected animals and reduced soil degradation
• Maintenance of unobstructed key wildlife migration corridors
• Funding of soil restoration research at African universities

World Wildlife Magazine, 2016

Wildlife

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Stoldt, M., Göttert, T., Mann, C., & Zeller, U.. (2020). Transfrontier Conservation Areas and Human-Wildlife Conflict: The Case of the Namibian Component of the Kavango-Zambezi (KAZA) TFCA. Scientific Reports, 10(1). https://doi.org/10.1038/s41598-020-64537-9

Wildlife

Each country within the KAZA region is faced with different problems

• Angola is experiencing rapid development and water is being diverted to supply the demands of the growing economy and population
• Along the Angolan stretches of the Cubango and Cuito Rivers, commercial bushmeat trade and slash-and-burn farming practices have become the major sources of income

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• Botswana is receiving significantly lower amounts of water during the flood season (due to climate change and diversion of water upstream).
• Already seeing the impacts of climate change as there is an increase in human-wildlife conflict over water resources
• It is likely that seasonally flooded areas of the Delta, where most large mammals are found, will be severely affected if the Delta shrinks.

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Conclusions

• Climate
• Shorter wet season, overall decrease in total rainfall with less frequent yet more intense rain events.
• More frequent short duration droughts, but little change in drought severity.
• Hydrology
• Studies on water issue are needed because of inadequate data in the conservation area.
• Develop effective water management and conflict resolution strategies between member states
• Agriculture
• Agriculture, whether it be flood recession or dryland, is vital for livelihood of people and communities.
• Therefore, next steps should focus on: stabilizing and controlling both types of farming and well as figuring out how to divert rivers to increase consistency for all types of farming
• Livestock & Wildlife
• Expansion of livestock agriculture should be limited and must not obstruct wildlife migration corridors. Funding should support research of sustainable livestock farming practices at African universities.
• Educate countries/communities about the importance of safeguarding wildlife and the economic prospects of such ventures
• Encourage SADC and ZAMCOM to update policies on a regular basis and clearly highlight consequences of actions when state members fail to comply. These organizations should clearly state goals and how/when they will be achieved.
• Climate change will affect water resources which will cause an increase in human-wildlife conflict as competition for resources increase

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Research gaps & data that needs to be publically available

• Climate predictions are currently based on global climate models (with a horizontal resolution between 250-600 km). Much higher resolution regional climate models (horizontal resolution between 25-50 km) are needed to more accurately assess impacts of climate change.
• Generally, normalizing data across the Kaza region is lacking
• In terms of water management and data, there are not many (if any) probes or gauges used to monitor. Therefore, no real time data is available even for river gauges
• There’s lack of data on soil moisture, nutrients/organic matter within soil, water holding capacity, and soil biological activity to name a few.
• Not much research is done in the KAZA TFCA about how climate scale will directly affect wildlife. However, looking at Climate Change impact on water resources can give indication of species distribution (both flora and fauna)
• More research needs to be done that takes forestry inventory and look at how native plants can improve ecosystems (whether improve soil, water retention, wildlife distribution etc)
• Data needs to be normalized throughout the region. This can be done through efforts of SADC or ZAMCOM by requiring member states to readily have environmental data at hand. Environmental variables such as hydraulic capacity, forest cover index, soil moisture, wildlife tracking etc

References

Dunning, C. M., Black, E., & Allan, R. P. (2018). Later wet seasons with more intense rainfall over Africa under future climate change. Journal of Climate, 31(23): 9719-9738.

Falchetta, G., Gernaat, D. E., Hunt, J., & Sterl, S. (2019). Hydropower dependency and climate change in sub-Saharan Africa: A nexus framework and evidence-based review. Journal of cleaner production, 231: 1399-1417.

Garcia, G., Morris, J., Lee, G. (2020). Flows of Water and Wildlife in KAZA. Master’s thesis, Duke University. Duke Space Library.

Gizaw, M. S., & Gan, T. Y. (2017). Impact of climate change and El Niño episodes on droughts in sub-Saharan Africa. Climate Dynamics, 49(1-2): 665-682.

Huang, J., Zhang, G., Zhang, Y., Guan, X., Wei, Y., & Guo, R. (2020). Global desertification vulnerability to climate change and human activities. Land Degrad Dev., 31: 1380–1391.

Kashe, K., Mogobe, O., Moroke, T., & Murray-Hudson, M. (2015). Evaluation of maize yield in flood recession farming in the Okavango Delta, Botzwana. African Journal of Agricultural. 10(16): 1874-1879.

Molefe, C., Cassidy, L., Chimbari, Magole, L. (2014). Influence of Flooding Variation on Molapo Farming Field Size in the Okavango Delta, Botswana. Int. J. Agric. 2(2): 27-37.

Nazarenko, L., Schmidt, G. A., Miller, R. L., Tausnev, N., Kelley, M., Ruedy, R., ... & Zhang, J. (2015). Future climate change under RCP emission scenarios with GISS M odelE2. Journal of Advances in Modeling Earth Systems, 7(1): 244-267.

Serdeczny, O., Adams, S., Baarsch, F., Coumou, D., Robinson, A., Hare, W., ... & Reinhardt, J. (2017). Climate change impacts in Sub-Saharan Africa: from physical changes to their social repercussions. Regional Environmental Change, 17(6): 1585-1600.

Stoldt, M., Göttert, T., Mann, C., & Zeller, U.. (2020). Transfrontier Conservation Areas and Human-Wildlife Conflict: The Case of the Namibian Component of the Kavango-Zambezi (KAZA) TFCA. Scientific Reports, 10(1). https://doi.org/10.1038/s41598-020-64537-9

Thomson, G. R., Penrith, M. L., Atkinson, M. W., Atkinson, S. J., Cassidy, D., & Osofsky, S. A. (2013). Balancing livestock production and wildlife conservation in and around Southern Africa’s transfrontier conservation areas. Transboundary and Emerging Diseases, 60: 492-506.

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References

Food and Agriculture Organization of the United Nations (FAO). Country Fact Sheet—Angola/ Namibia

/ Botswana, 2012. Available online: http://www.fao.org/nr/water/aquastat/data/factsheets/

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Ashton, P. (2003). The search for an equitable basis for water sharing in the Okavango River basin. International Waters in Southern Africa, 164-188.

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