Evaluation of prediction models is crucial to achieving valid information on erosion processes and their management choices.WEPP model efficiency in predicting ephemeral gully(EG)erosion was recently tested and compar...Evaluation of prediction models is crucial to achieving valid information on erosion processes and their management choices.WEPP model efficiency in predicting ephemeral gully(EG)erosion was recently tested and compared with both EGEM and empirical models.The models abilities to predict EG erosion were validated using measured estimates at the 6 eroding locations around Mubi area in Northeast Nigeria between April 2008 and October 2009.Each location consisted of 3 watersheds where data on soils,climate,slope,management practices,EG shapes and dimensions were collected.Data on relevant soil properties were collected in the field and then analyzed in laboratory.The mass of soil loss(MSL)predicted by empirical,EGEM and WEPP models were compared with the measured using paired T-test,regression graphs(r^(2)-values),error analysis,and analysis of variance(ANOVA)in a completely ran-domized design.The EG erosion losses varied significantly(P≤0.05)between sites and years.No sig-nificant(P≤0.05)differences were observed between measured and the empirically predicted aggregate MSL.The measured aggregate MSL strongly correlated with those predicted by empirical(r^(2)=0.67),than with EGEM(r^(2)=0.57),and WEPP(r^(2)=0.53)models.Slight over and under-prediction instances against the measured erosion were noted with all the models.The WEPP model was found to slightly over-predict MSL when compared to either the empirical or EGEM model.The prediction quality of the models was generally impressive.Future works should focus more on local inputs such as climate,plants,management,and tillage data for use with WEPP.展开更多
A field adaptation test of the Ephemeral Gully Erosion Model(EGEM)to predict ephemeral gully(EG)erosion was carried out in the 2008 and 2009 farming seasons in the Mubi area,NE Nigeria.Land use,conservation practices,...A field adaptation test of the Ephemeral Gully Erosion Model(EGEM)to predict ephemeral gully(EG)erosion was carried out in the 2008 and 2009 farming seasons in the Mubi area,NE Nigeria.Land use,conservation practices,and EG channel features were measured and/or noted at each site.Soil loss varied among the sites and seasons.The measured area,volume,and mass of soil loss were used to test the standard EGEM_(std),and the adapted models'(EGEM_(Ad) and EGEM_(Al))prediction efficiencies.The result showed that EGEM_(std) could not predict the area of soil loss adequately.Both EGEM_(Ad) and EGEM_(Al) were efficient and better adapted to predicting area,volume,and mass loss from EG erosion.The adapted models are therefore strongly recommended for implementation in the study area.展开更多
文摘Evaluation of prediction models is crucial to achieving valid information on erosion processes and their management choices.WEPP model efficiency in predicting ephemeral gully(EG)erosion was recently tested and compared with both EGEM and empirical models.The models abilities to predict EG erosion were validated using measured estimates at the 6 eroding locations around Mubi area in Northeast Nigeria between April 2008 and October 2009.Each location consisted of 3 watersheds where data on soils,climate,slope,management practices,EG shapes and dimensions were collected.Data on relevant soil properties were collected in the field and then analyzed in laboratory.The mass of soil loss(MSL)predicted by empirical,EGEM and WEPP models were compared with the measured using paired T-test,regression graphs(r^(2)-values),error analysis,and analysis of variance(ANOVA)in a completely ran-domized design.The EG erosion losses varied significantly(P≤0.05)between sites and years.No sig-nificant(P≤0.05)differences were observed between measured and the empirically predicted aggregate MSL.The measured aggregate MSL strongly correlated with those predicted by empirical(r^(2)=0.67),than with EGEM(r^(2)=0.57),and WEPP(r^(2)=0.53)models.Slight over and under-prediction instances against the measured erosion were noted with all the models.The WEPP model was found to slightly over-predict MSL when compared to either the empirical or EGEM model.The prediction quality of the models was generally impressive.Future works should focus more on local inputs such as climate,plants,management,and tillage data for use with WEPP.
文摘A field adaptation test of the Ephemeral Gully Erosion Model(EGEM)to predict ephemeral gully(EG)erosion was carried out in the 2008 and 2009 farming seasons in the Mubi area,NE Nigeria.Land use,conservation practices,and EG channel features were measured and/or noted at each site.Soil loss varied among the sites and seasons.The measured area,volume,and mass of soil loss were used to test the standard EGEM_(std),and the adapted models'(EGEM_(Ad) and EGEM_(Al))prediction efficiencies.The result showed that EGEM_(std) could not predict the area of soil loss adequately.Both EGEM_(Ad) and EGEM_(Al) were efficient and better adapted to predicting area,volume,and mass loss from EG erosion.The adapted models are therefore strongly recommended for implementation in the study area.
