Well what decade do you want to focus on? And what country/place are the immigrants going to? Are we talking immigration into the US for a single decade? Including slavery ? Would the people forced into the country still be considered immigrants
The answer to this question is the "Middle East".
Based on the map (I've searched the map), we need to identify the region on which would we expect environmental policy leaders to target for the most critical anti-deforestation efforts and the answer is the "Middle East".
