Stocking Density Effects of Small Indigenous Species (SIS) on Carp Polyculture Systems in Nepal

aquaculture;Nepal;carp;SIS;Natural Resources and Environment

Keeler, BaileyWiley, Michael ;

University of Michigan

关键词: aquaculture;    Nepal;    carp;    SIS;    Natural Resources and Environment;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/134694/Keeler_Bailey_Thesis_2016.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Smallindigenousspecies(SIS)addedtocarppolyculturepondsinNepalhaveincreasedproduction,economicreturns,andnutritionalwellbeingforfarmers.However,therehasbeenlittleresearchtodetermineanoptimalstockingdensityofSIS.Thus,themainobjectiveofthisexperimentwastoidentifyanoptimalstockingdensitytopromoteoverallpondproductionandprofitsofatypicalsix-­‐speciescarppolyculturesysteminNepal.Thiswasaccomplishedbycomparingtheeffectsofthreedifferentstockingdensitiesofpunti(Puntiussophore)anddedhuwa(Esomusdanricus)oncarpproduction,SISnetgain,SISharvest,waterquality,andeconomicreturns.AsexpectedSISstockingdensityhadnosignificanteffectoncarpproductionorwaterquality.Stockingdensitynegativelyaffecteddedhuwanetgain,whichwastheproductofreproduction,survival,andimmigrationoremigrationfromponds,butdidnotaffectharvest.Conversely,stockingdensitydidnotaffect puntinetgain,butdidpositivelyaffectharvest.Althoughstockedpondsexperiencedvariablenetgainofpunti,theyhadhigherharveststhanpondswithnostocking.Fordedhuwaandcarp,isolationandaveragesizeatstockingbestpredictednetgain.BudgetanalysisshowedstockingofSIScouldincreaseprofitbyanaverageof$536/yr.AlthoughfarmersoftenreportedhighernetgainwithoutstockingSIS,stockingcouldcreateamorereliableharvestofpuntiandthusamorereliablesourceforhouseholdconsumptionorsales.