Fig. 2 Network of economic and political links between each pair of Nile basin countries and collaborative groups in the partial collaboration scenario. Between-country connections depicted as lines linking countries. Line width and color represent the strength of the link. (A) The median rank of all variables used to calculate trade connections between countries. (B) The number of shared international environmental agreements.
Fig. 3 Conservation priorities in the Nile Basin (subcatchments selected in Marxan’s best solutions) according to the scenario they were selected in. Yellow subcatchments were only selected in the “no collaboration” scenario, red subcatchments were selected in the “full collaboration” scenario, and orange subcatchments were selected in both scenarios.
Fig. 4 Selection frequency of Nile basin subcatchments. The number of times each subcatchment was selected as a priority out of 100 Marxan runs for (A) the no collaboration scenario, (B) the partial collaboration scenario, and (B) the full collaboration scenario. Planning units in dark blue were found to be highly irreplaceable for conservation and are therefore conservation priorities; planning units in beige were not included in this analysis.
- Table 1 The collaboration scenarios among Nile basin countries examined in this study.
Scenarios Actors No collaboration scenario All countries act individually
(current situation; business as
usual)Partial collaboration scenario Egypt and Ethiopia collaborate,
the East African community
collaborates (Kenya, Tanzania,
Uganda, Burundi, and Rwanda),
and the remaining countries
act individually (Sudan, South
Sudan, Eritrea, and DRC)Full collaboration scenario Full between-country
collaboration across the whole
Nile basin - Table 2 Total cost (BHM in millions of U.S. dollars), cost as a percentage increase above that of the full collaboration scenario, area (in km2), human population, and cumulative biodiversity threat score of subcatchments selected in the Marxan “best solution” (see Materials and Methods).
Collaboration scenario Cost (BHM in millions
of U.S. dollars)Cost as % increase
above full
collaborationHuman population Cumulative
biodiversity threat
scoreArea (km2) No collaboration 334.4 34.0 24,816,395 259.5 328,950.0 Partial collaboration 265.5 6.4 19,943,873 255.7 294,434.0 Full collaboration 249.5 0.0 16,041,420 235.5 260,134.0 - Table 3 Total cost of achieving 17% conservation targets and the proportion that each country pays in the three collaboration scenarios (no, partial, and full collaboration), assuming that each country only pays for conservation actions within its own area (cost = BHM in millions of U.S. dollars of the best solution in Marxan).
Cost BHM (millions of U.S. dollars) Proportion of total cost (%) Cost savings (millions of U.S.
dollars) through collaborationCollaboration scenarios Collaboration scenarios Collaboration scenarios Country No Partial Full No Partial Full Partial Full Burundi 7.23 3.66 2.46 2.16 1.38 0.99 −3.57 −4.77 DRC 1.08 0.94 0.54 0.32 0.35 0.22 −0.14 −0.54 Egypt 194.37 192.35 189.56 58.12 72.45 75.97 −2.02 −4.81 Eritrea 0.91 0.93 0.00 0.27 0.35 0.00 0.02 −0.91 Ethiopia 15.49 10.04 7.62 4.63 3.78 3.05 −5.45 −7.87 Kenya 53.07 7.72 1.28 15.87 2.91 0.51 −45.35 −51.79 Rwanda 3.42 2.83 3.21 1.02 1.07 1.29 −0.59 −0.21 South Sudan 2.17 2.50 2.57 0.65 0.94 1.03 0.33 0.40 Sudan 21.71 15.17 6.86 6.49 5.71 2.75 −6.54 −14.85 Tanzania 15.31 8.47 17.72 4.58 3.19 7.10 −6.84 2.41 Uganda 19.61 20.94 17.74 5.86 7.89 7.11 1.33 −1.87
Supplementary Materials
Supplementary material for this article is available at http://advances.sciencemag.org/cgi/content/full/5/4/eaau7668/DC1
Fig. S1. Freshwater richness for 331 fish species in the river Nile.
Fig. S2. Spatial distribution of the BHM.
Fig. S3. Distribution of economic variables in the Nile basin in 2012.
Fig. S4. The distribution of socioeconomic and political factors in the Nile basin.
Table S1. Demographic and trade data for each Nile basin country (listed in order from north to south).
Table S2. General geographic and protected area statistics for each of the Nile basin countries.
Additional Files
Supplementary Materials
This PDF file includes:
- Fig. S1. Freshwater richness for 331 fish species in the river Nile.
- Fig. S2. Spatial distribution of the BHM.
- Fig. S3. Distribution of economic variables in the Nile basin in 2012.
- Fig. S4. The distribution of socioeconomic and political factors in the Nile basin.
- Table S1. Demographic and trade data for each Nile basin country (listed in order from north to south).
- Table S2. General geographic and protected area statistics for each of the Nile basin countries.
Files in this Data Supplement:
