3901
Although we could not clearly attribute these differences strictly to differences in assimilation of carbon from terrestrial or in - channel sources , greater potential for benthic primary production at more open sites might play a role .
 Chemical: carbon
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: carbon 
Answer:
 Chemical: carbon