We explore the long run determinants of current differences in the degree of cooperative labor relations at local level. We do this by estimating the causal effect of the medieval communes - that were established in certain cities in Centre-Northern Italy towards the end of the 11th century -...

Nutrient enrichment of marine ecosystems is regarded as a pressing global environmental problem. For certain marine species it may be a mixed blessing, resulting in damaging ecosystem events, but contributing to primary productivity. Consequently, the impact of enrichment on fishery profits may...

There is now increasing recognition that the world's marine ecosystems, especially coastal areas and semi-enclosed seas, are suffering from degradation and modification due to human influences. One of the most serious problems is nutrient enrichment, which in the long term harms productivity and...