关键词: 中层取水；钉螺；费用一效益

Abstract:

Objective  To evaluate the cost-benefit of the project with the mode of collecting wa-
ter from middle layer of water body by the culvert pipelinet. Methods  The cost-benefit analysis
was carried out by the way of benefit-cost ratio for the project with the mode of collecting water
from middle layer of water body by the culvert pipelinet without indirect cost and indirect benefit,
and according to the price of 2005. Results  The direct costs was 34 thousand yuans in the project
with the mode of collecting water from middle layer of water body by the culvert pipelinet. The
saved costs of prevention and treatment were 1 011 thousand yuans, the net benefit was 977 thou-
sand yuans and the net benefit-cost ratio was 28. 7 : 1 following the project implemented. Conclu-
sion  The investment is small but the benefit is high in the project of collecting water from middle
layer of water body by the culvert pipelinet. The technique has the notable worthiness of applica-
tions.

Key words:  , Collecting water from middle layer, On,comelan,ia hupensis, Cost-benefit