Introduction:Rangelands are important source of pasture for livestock in Kenya since time immemorial to pastoral households.However,seasonality on forage availability has been a big challenge in meeting animals’feed ...Introduction:Rangelands are important source of pasture for livestock in Kenya since time immemorial to pastoral households.However,seasonality on forage availability has been a big challenge in meeting animals’feed requirements.This demands harvest and storage of pastures for use during dry seasons.Hay making has been done to bridge this forage deficit periods.However,hay quality in the rangelands is affected by curing methods,phonological stage at harvest,and the storage duration.We therefore evaluated the effect of field curing and storage duration on the quality(Crude Protein(CP))of hay from six rangeland grasses in Kenya.Methods:The grasses evaluated are Chloris roxburghiana,Eragrostis superba,Enteropogon macrostachyus,Cenchrus ciliaris,Chloris gayana,and Sorghum sudanense.These grasses are the common species in the rangelands of Kenya and have been promoted in the past for hay making and reseeding interventions.The grasses were harvested at the mature flowering stage(12 weeks phenological stage),which is a period that provides high biomass without much effect on quality as practiced in the study area.The grasses were then cured in the field for 1,2,and 3 days before baling and stored indoors for 12,24,and 36 weeks.Samples were taken for CP content determination at the three periods following Macro-Kjeldahl Method.Results:There was significant decline(p≤0.05)in crude protein content in all the grass species with storage periods.Curing period did not affect the CP content for all the species at a given storage period;however,3 days curing changed the hay color from green to brownish which reduces palatability and consequently reduced feed intake.Storage period of over 12 weeks adversely lowered CP to less than 6% for all the species which is the required minimum level for animal under production and maintenance.S.Sudanense had significantly higher decline in CP after 24 weeks storage compared to the other species.Conclusions:Therefore,hay from the six grass species harvested at mature flowering stage(12-week phonological stage)and stored longer than 12 weeks supplies the animals with low CP.Also,to maintain palatability,1-2 days curing is recommended for the six grass species.展开更多
Introduction:Scarcity of water in the rangelands of Kenya has led to the introduction of piospheres.Previous research has however produced contrasting results on the effects of piospheres and seasonality on ShannonWi...Introduction:Scarcity of water in the rangelands of Kenya has led to the introduction of piospheres.Previous research has however produced contrasting results on the effects of piospheres and seasonality on ShannonWiener’s diversity index,and therefore,this information is still deficient.In this study,the impact of these piospheres on plant species composition,diversity,and richness was assessed.Methods:Vegetation sampling was done during both the long rains(April)and the dry season(August).Three piosphere types(dam,trough,and a seasonal river)were studied using 0.25 m2 quadrats to sample vegetation at intervals of 20 m along 100-m transects.Four 100-m transects were used per piosphere(north,east,south,and west directions).Shannon-Wiener’s diversity index was used to determine species richness and composition.Twoway ANOVA was used to determine if piospheric distance had an effect on species diversity,richness,and evenness using GenStat 15th edition.Results:A total of 22 grasses and 29 forbs were recorded in the study area.The most abundant grasses near the piospheres were Eragrostis tenuifolia(12.9%)and Cynodon dactylon(10.6%).E.tenuifolia is an increaser species and was therefore most abundant in areas of severe grazing while C.dactylon has been known to be tolerant to grazing.The most abundant forbs were Crotalaria brevidens(37.5%).The Shannon-Wiener diversity index significantly increased(F=25.07,P=0.001)with distance from the three piospheres owing to the high grazing intensity near the piospheres and was significantly different between piospheres,being higher(F=10.05,P=0.001)at 20 m from the river(1.2±0.1)compared to a similar distance from the dam(0.9±0.1)and the trough(0.8±0.2).This was probably because the trough was smaller in size compared to the other piospheres,thereby concentrating more grazing animals per unit area and causing a greater impact on plant species.Conclusions:The study demonstrated that species diversity,richness,and evenness were low near the piospheres due to heavy grazing.Similarly,the lowest species diversity,richness,and evenness were recorded near the trough compared to the dam and the river.This study therefore recommends that range reseeding and rest period be done to rehabilitate degraded areas and facilitate plant regeneration.Larger piospheres should also be used to minimize animal impact per unit area.展开更多
Introduction:Land degradation is a serious environmental problem of our time.In Kenya,it is estimated that 30%of the total land mass is severely degraded.Suswa catchment within Narok County is a good example with gull...Introduction:Land degradation is a serious environmental problem of our time.In Kenya,it is estimated that 30%of the total land mass is severely degraded.Suswa catchment within Narok County is a good example with gullies of over 25 m deep and 30 m wide.In response to the increasing land degradation in the area,the Sustainable Land Management(SLM)project rehabilitated the catchment through establishment of soil and water conservation structures such as cutoff drains,semicircular bunds,and water retention ditches.Despite the various rehabilitation approaches carried out,little research has been done to ascertain their effect on successful vegetation recovery.This coupled with the fact that many restoration approaches have failed in East Africa and Kenya in particular gave drive to the study.The objective of this study was to determine the effects of rangeland rehabilitation on herbaceous species composition and diversity in a severely degraded rangeland.Methods:To assess the diversity of aboveground herbaceous layer in the rehabilitated and degraded areas along a slope(upper,middle,and lower),line transect and quadrat count methods were used.Within each slope position,three 100-m-long transects were placed across the hill parallel to one another 30 m apart using a tape.The species hit,the closest species to the hit,and hits on bare ground were recorded.Along the same transects,1-m2 quadrats were placed 25 m apart and aboveground biomass determined by the use of the destructive method.In the determination of species richness,diversity,relative abundance,percentage cover,and species composition,the Shannon-Wiener diversity index was used.Data collected on vegetation attributes was subjected to analysis of variance(ANOVA)using Genstat and Tukey’s HSD post hoc used in means separation where F values were significant.Results:The results showed that percent cover(74.67%),aboveground biomass(1459 kg/ha),relative abundance,richness,composition,and diversity of perennial grasses significantly(P≤0.05)increased downslope and were higher in the rehabilitated area than in the degraded area.On the contrary,forbs and annual grasses were significantly(P≤0.05)higher within the degraded area compared to the rehabilitated area and increased upslope.Conclusions:In general,herbaceous species diversity,species richness,relative abundance,percentcomposition,biomass production,and percent cover of perennial grasses significantly increased downslopeand were higher in the rehabilitated area compared to the degraded area.On the contrary,the sameattributes for forbs and annual grasses were higher in the degraded area and increased upslope.The studyconcluded that effective rangeland rehabilitation has the potential to enhance vegetation regeneration andhence forage productivity.Conclusions:ln general,herbaceous species diversity,species richness,relative abundance,percent composition,biomass production,and percent cover of perennial grasses significantly increased downslopeand were higher in the rehabilitated area compared to the degraded area On the contrary,the same attributes for forbs and annual grasses were higher in the degraded area and increased upslope.The studyconduded that effective rangeland rehabilitation has the potential to enhance vegetation regeneration andhence forage productivity.展开更多
Introduction:Water-based interventions haphazardly introduced in the drylands of Kenya have led to the introduction of piospheres used as concentration mounts.Not much is known about the effect of these piospheres on ...Introduction:Water-based interventions haphazardly introduced in the drylands of Kenya have led to the introduction of piospheres used as concentration mounts.Not much is known about the effect of these piospheres on soil physio-chemical properties,especially in the Kenyan rangelands where the government and other development agencies have created piospheres aimed at curbing water shortages and sustaining livestock production.The study assessed the effect of piospheres on soil physio-chemical characteristics in the southern rangelands of Kajiado,Kenya,in order to provide evidence-based insights that will be useful in guiding future water interventions.Methods:Soil samples were collected within 0.25-m2 plots at 20-m intervals along 100-m transects from three piospheres(a dam,a trough,and a seasonal river).Two-way ANOVA was used to determine if there were significant differences in soil parameters between piospheric distances.Results:Soil bulk density significantly different between piospheric distances(F=22.25,P=0.001)and piospheres(F=13.10,P=0.002),being highest at 20 m from the trough(1.1–1.21 gcm−3)relative to a similar distance from the dam(1.01–1.20 gcm−3)and the river(1.1–1.17 gcm−3).On the other hand,mean soil aggregate stability significantly increased(F=66.89,P=0.001)with piospheric distance,being lowest at 20 m from the trough(43.9–46.2%),the dam(43.1–48.9%),and the river(46.6–47.5%).Conclusions:High soil bulk density and consequent low soil porosity,hydraulic conductivity,and moisture content demonstrated that grazing was high near the piospheres.It is recommended that livestock should be herded away from the piospheres after drinking water to ensure that grazing livestock spend less time near the piospheres if reduced soil compaction is to be realized.Piospheres should also be better planned and placed at landscape level to exploit landscape heterogeneity.展开更多
基金supported by the National Irrigation Board(NIB)Kenya,Government of Kenya through the National Council of Science,Technology and Innovation(NACOSTI),German Academic Exchange Service(DAAD),and the Centre for Sustainable Dryland Ecosystems and Societies(CSDES)-University of Nairobi,Kenya。
文摘Introduction:Rangelands are important source of pasture for livestock in Kenya since time immemorial to pastoral households.However,seasonality on forage availability has been a big challenge in meeting animals’feed requirements.This demands harvest and storage of pastures for use during dry seasons.Hay making has been done to bridge this forage deficit periods.However,hay quality in the rangelands is affected by curing methods,phonological stage at harvest,and the storage duration.We therefore evaluated the effect of field curing and storage duration on the quality(Crude Protein(CP))of hay from six rangeland grasses in Kenya.Methods:The grasses evaluated are Chloris roxburghiana,Eragrostis superba,Enteropogon macrostachyus,Cenchrus ciliaris,Chloris gayana,and Sorghum sudanense.These grasses are the common species in the rangelands of Kenya and have been promoted in the past for hay making and reseeding interventions.The grasses were harvested at the mature flowering stage(12 weeks phenological stage),which is a period that provides high biomass without much effect on quality as practiced in the study area.The grasses were then cured in the field for 1,2,and 3 days before baling and stored indoors for 12,24,and 36 weeks.Samples were taken for CP content determination at the three periods following Macro-Kjeldahl Method.Results:There was significant decline(p≤0.05)in crude protein content in all the grass species with storage periods.Curing period did not affect the CP content for all the species at a given storage period;however,3 days curing changed the hay color from green to brownish which reduces palatability and consequently reduced feed intake.Storage period of over 12 weeks adversely lowered CP to less than 6% for all the species which is the required minimum level for animal under production and maintenance.S.Sudanense had significantly higher decline in CP after 24 weeks storage compared to the other species.Conclusions:Therefore,hay from the six grass species harvested at mature flowering stage(12-week phonological stage)and stored longer than 12 weeks supplies the animals with low CP.Also,to maintain palatability,1-2 days curing is recommended for the six grass species.
文摘Introduction:Scarcity of water in the rangelands of Kenya has led to the introduction of piospheres.Previous research has however produced contrasting results on the effects of piospheres and seasonality on ShannonWiener’s diversity index,and therefore,this information is still deficient.In this study,the impact of these piospheres on plant species composition,diversity,and richness was assessed.Methods:Vegetation sampling was done during both the long rains(April)and the dry season(August).Three piosphere types(dam,trough,and a seasonal river)were studied using 0.25 m2 quadrats to sample vegetation at intervals of 20 m along 100-m transects.Four 100-m transects were used per piosphere(north,east,south,and west directions).Shannon-Wiener’s diversity index was used to determine species richness and composition.Twoway ANOVA was used to determine if piospheric distance had an effect on species diversity,richness,and evenness using GenStat 15th edition.Results:A total of 22 grasses and 29 forbs were recorded in the study area.The most abundant grasses near the piospheres were Eragrostis tenuifolia(12.9%)and Cynodon dactylon(10.6%).E.tenuifolia is an increaser species and was therefore most abundant in areas of severe grazing while C.dactylon has been known to be tolerant to grazing.The most abundant forbs were Crotalaria brevidens(37.5%).The Shannon-Wiener diversity index significantly increased(F=25.07,P=0.001)with distance from the three piospheres owing to the high grazing intensity near the piospheres and was significantly different between piospheres,being higher(F=10.05,P=0.001)at 20 m from the river(1.2±0.1)compared to a similar distance from the dam(0.9±0.1)and the trough(0.8±0.2).This was probably because the trough was smaller in size compared to the other piospheres,thereby concentrating more grazing animals per unit area and causing a greater impact on plant species.Conclusions:The study demonstrated that species diversity,richness,and evenness were low near the piospheres due to heavy grazing.Similarly,the lowest species diversity,richness,and evenness were recorded near the trough compared to the dam and the river.This study therefore recommends that range reseeding and rest period be done to rehabilitate degraded areas and facilitate plant regeneration.Larger piospheres should also be used to minimize animal impact per unit area.
文摘Introduction:Land degradation is a serious environmental problem of our time.In Kenya,it is estimated that 30%of the total land mass is severely degraded.Suswa catchment within Narok County is a good example with gullies of over 25 m deep and 30 m wide.In response to the increasing land degradation in the area,the Sustainable Land Management(SLM)project rehabilitated the catchment through establishment of soil and water conservation structures such as cutoff drains,semicircular bunds,and water retention ditches.Despite the various rehabilitation approaches carried out,little research has been done to ascertain their effect on successful vegetation recovery.This coupled with the fact that many restoration approaches have failed in East Africa and Kenya in particular gave drive to the study.The objective of this study was to determine the effects of rangeland rehabilitation on herbaceous species composition and diversity in a severely degraded rangeland.Methods:To assess the diversity of aboveground herbaceous layer in the rehabilitated and degraded areas along a slope(upper,middle,and lower),line transect and quadrat count methods were used.Within each slope position,three 100-m-long transects were placed across the hill parallel to one another 30 m apart using a tape.The species hit,the closest species to the hit,and hits on bare ground were recorded.Along the same transects,1-m2 quadrats were placed 25 m apart and aboveground biomass determined by the use of the destructive method.In the determination of species richness,diversity,relative abundance,percentage cover,and species composition,the Shannon-Wiener diversity index was used.Data collected on vegetation attributes was subjected to analysis of variance(ANOVA)using Genstat and Tukey’s HSD post hoc used in means separation where F values were significant.Results:The results showed that percent cover(74.67%),aboveground biomass(1459 kg/ha),relative abundance,richness,composition,and diversity of perennial grasses significantly(P≤0.05)increased downslope and were higher in the rehabilitated area than in the degraded area.On the contrary,forbs and annual grasses were significantly(P≤0.05)higher within the degraded area compared to the rehabilitated area and increased upslope.Conclusions:In general,herbaceous species diversity,species richness,relative abundance,percentcomposition,biomass production,and percent cover of perennial grasses significantly increased downslopeand were higher in the rehabilitated area compared to the degraded area.On the contrary,the sameattributes for forbs and annual grasses were higher in the degraded area and increased upslope.The studyconcluded that effective rangeland rehabilitation has the potential to enhance vegetation regeneration andhence forage productivity.Conclusions:ln general,herbaceous species diversity,species richness,relative abundance,percent composition,biomass production,and percent cover of perennial grasses significantly increased downslopeand were higher in the rehabilitated area compared to the degraded area On the contrary,the same attributes for forbs and annual grasses were higher in the degraded area and increased upslope.The studyconduded that effective rangeland rehabilitation has the potential to enhance vegetation regeneration andhence forage productivity.
文摘Introduction:Water-based interventions haphazardly introduced in the drylands of Kenya have led to the introduction of piospheres used as concentration mounts.Not much is known about the effect of these piospheres on soil physio-chemical properties,especially in the Kenyan rangelands where the government and other development agencies have created piospheres aimed at curbing water shortages and sustaining livestock production.The study assessed the effect of piospheres on soil physio-chemical characteristics in the southern rangelands of Kajiado,Kenya,in order to provide evidence-based insights that will be useful in guiding future water interventions.Methods:Soil samples were collected within 0.25-m2 plots at 20-m intervals along 100-m transects from three piospheres(a dam,a trough,and a seasonal river).Two-way ANOVA was used to determine if there were significant differences in soil parameters between piospheric distances.Results:Soil bulk density significantly different between piospheric distances(F=22.25,P=0.001)and piospheres(F=13.10,P=0.002),being highest at 20 m from the trough(1.1–1.21 gcm−3)relative to a similar distance from the dam(1.01–1.20 gcm−3)and the river(1.1–1.17 gcm−3).On the other hand,mean soil aggregate stability significantly increased(F=66.89,P=0.001)with piospheric distance,being lowest at 20 m from the trough(43.9–46.2%),the dam(43.1–48.9%),and the river(46.6–47.5%).Conclusions:High soil bulk density and consequent low soil porosity,hydraulic conductivity,and moisture content demonstrated that grazing was high near the piospheres.It is recommended that livestock should be herded away from the piospheres after drinking water to ensure that grazing livestock spend less time near the piospheres if reduced soil compaction is to be realized.Piospheres should also be better planned and placed at landscape level to exploit landscape heterogeneity.
