Table 4. Difference in practices for certified farms before and after joining certification (n = 43)

Current Before certification Wilcoxon/McNemar test p - value
Median values
Ecosystem conservation
Number of tree species per hectare 9 5 415.5 0.000*
Number of farmers who planted trees outside the coffee plots 32 10 20.045 0.000*
Number of farmers who protect water sources through fencing and reforestation
 
31
 
23
 
6.125
 
0.013*
 
Water conservation and water discharge
Number of farmers who use water-saving technologies for depulping 32 18 12.071 0.001*
Number of farmers who have grease traps in the kitchen 42 8 30.250 0.000*
Number of farmers who throw waste water to the field 2 28 22.321 0.000*
Integrated crop management
Number of farmers who collect ripe and over-ripe fruits
 
39 21 14.450 0.001*
Soil management and conservation
Number of farmers who use soil analysis
 
10 1 5.818 0.016*
Integrated waste management
Number of farmers who collect trash from the field 41 6 33.029 0.000*
Number of farmers who recycle 41 2 37.026 0.000*
Number of farmers who burn or bury trash 2 40 36.026 0.000*
* Significant at the 0.05 level.
n = 33 pairs: Not all farms have water sources in or adjacent to the property. The comparison includes only those for whom the question is relevant.
Wilcoxon test applies for continuous variables and McNemar for dichotomous ones.