The State of World Fisheries and Aquaculture 2020

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PART 3 
OUTLOOK AND EMERGING ISSUES
TABLE 20
VARIABLES USED IN THE THREAT ASSESSMENT FOR INLAND FISHERIES
Major threat
Subindicators
Population-related
Population density; gross domestic product; road accessibility
Loss of connectivity
Dams; barrages, weirs, dykes and other barriers; channelization; dredging
Land use
Deforestation, land degradation; mining; sedimentation; nitrogen runoff; 
phosphorous runoff, agricultural land use
Climate variability
Temperature increase/decrease/variability; precipitation increase/decrease/
variability; predicted extreme climate events
Water use
For irrigation, agriculture; industry; urban and human consumption
Pollution
Pesticides, other chemical runoff; plastics, pharmaceuticals, other pollution; 
aquaculture effluents; urban sewage
SOURCE: Drawn from IPBES, 2019.
FIGURE 57
GLOBAL “STATUS MAP” BASED ON THE INTERACTION OF 20 PRESSURES AT BASIN LEVEL
FOR THE 34 INDICATIVE BASINS THAT SUPPORT INLAND FISHERIES
NOTE: Basins outlined in white represent about 95% of global inland fisheries catch.
SOURCE: Unpublished data from US Geological Survey, Land and Water Lab at the University of Florida.
THREAT SCORE
N/A
1
2
3
4
5
6
7
8
9
10
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THE STATE OF WORLD FISHERIES AND AQUACULTURE 
2020
the drivers measured may increase fishery 
productivity rather than constrain it. 
This work is an ongoing programme under 
the United States Geological Survey. 
Upon completion, the threat-mapping GIS layer 
will be freely available through ScienceBase 
and other open-source information systems. 
ScienceBase will serve as the data repository, 
a catalogue of code and data processing 
documentation, and a link to acquired datasets 
and relevant collaborations (United States 
Geological Survey, 2020). It is expected that at 
the aggregated, global scale, data layers will 
only change significantly over a five-to-ten-year 
period, and this would be the typical time 
frame for periodic updates on a global state of 
threats to the inland fisheries. FAO will be able 
to use the information and data generated for 
further analysis and linkage to capture fisheries 
reporting, preferably at the subnational level. 
The mapping in 
Figure 58
identifies areas that 
are most prone to negative impacts as a result 
of pressures from increased eutrophication, 
high population density, pollution, land use 
and habitat fragmentation. It can provide 
insight as to where effort should be directed to 
understand the consequences of these pressures, 
especially if the area has a high catch or is of