Leitch lists a large number of beneficial functions performed by wetlands. 

 These include provision of natural firebreaks, expediting the global cycling of 

 nitrogen and sulfur, historical value, forestry products, shoreline protection, 

 erosion control, endangered species habitat, wildlife habitat, primary 

 productivity, flood control, and groundwater recharge. 



The wetland allocation problem is usually described as the problem of 

 selecting the socially optimal wetland acreage that should be preserved, given 

 the social constraint that drained wetlands provide sizeable market returns, but 

 wetland acreage provides socially significant nonmarket benefits. This raises 

 two problems: (1) determining the socially optimal wetland acreage, and 

 (2) devising regulatory mechanisms that preserve the desired wetland acreage. 

 As Leitch points out, this national perspective ignores certain complexities. 

 Namely, the regional rural economies in which the wetlands exist gain tax 

 receipts and augmented regional expenditure flows as wetlands are drained; they 

 lose tax receipts and regional income as more wetlands are preserved. 



47, Leitch, J. A. 1981b. Valuation of prairie wetlands. Ph.D. Thesis. 

 University of Minnesota, Minneapolis. 188 pp. 



Leitch discusses the wetlands of the Atlantic and Gulf of Mexico coasts, 

 inland Massachusetts, the Lake Michigan coastal wetlands of the State of 

 Michigan, and the coastal marshes of Virginia, as well as the prairie pothole 

 wetlands of the great plains. The author believes that he has shown that average 

 wetlands values tend to approximate marginal values. This implies that the 

 marginal values of wetlands preservation benefits are almost always positive 

 because total preservation benefits for many wetlands functions are sizeable. 

 Moreover, Leitch argues that the prairie potholes wetlands of the northern plains 

 of the U.S. and southern Canada can be restored after drainage. Again, this 

 simplifies the benefits estimation problem considerably because the irre- 

 versibility constraint on social investment might complicate the problem of 

 selecting the optimal stock of social capital (wetland acreage). 



The bulk of Minnesota farmers who have drained on-farm wetlands enjoyed 

 a positive return on their investment, although some farmers undertook investment 

 in drainage even though they anticipated low pecuniary returns. For these 

 operators, drainage had a high nuisance removal value. Leitch does not actually 

 provide empirical estimates of the values of various wetlands functions in this 

 work. 



48. Leitch, J. A. 1981c. Prairie wetlands allocation: an overview of landowner 

 alternatives and regional impacts. Pages 467-477 in B. Richardson, ed. 

 Selected proceedings of the midwest conference on wetland values and 

 management. Minnesota Water Planning Board, St. Paul. 



Leitch states that for farms in west-central Minnesota the net present 

 value of the return on random ditch drainage in 1981 was $141 per acre; on random 

 subsurface tile drainage the net annual return was $83 per acre; on general field 

 drainage investment in south-central Minnesota it was $630 per acre. The terms 

 "random" and "general field" that are used to describe drainage layouts 

 distinguish between the presence or absence of an orderly geometric pattern to 

 the tile lines or drainage ditches. In "random" or randomly selected layouts, 



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