The dynamics of most rangelands in Kenya remain to be poorly understood. This paper provides baseline information on the response of a semiarid rangeland under different livestock grazing regimes on land inhabited by ...The dynamics of most rangelands in Kenya remain to be poorly understood. This paper provides baseline information on the response of a semiarid rangeland under different livestock grazing regimes on land inhabited by the Massai people in the east side of Amboseli National Park in Kenya. The data were collected from grasslands designated into four types: (1) grassland from previous Massai settlements that had been abandoned for over twenty years; (2) grassland excluded from livestock grazing for eight years; (3) a dry season grazing area; and (4) a continuous grazing area where grazing occurred throughout all seasons. Collected data included grass species composition, grass height, inter-tuft distance, standing grass biomass and soil characteristics. The results indicated that continuous grazing area in semiarid rangelands exhibited loss of vegetation with negative, long-term effects on grass functional qualities and forage production, whereas grassland that used traditional Maasai grazing methods showed efficiency and desirable effects on the rangelands. The results also showed that abandoned homestead sites, though degraded, were important nutrient reservoirs.展开更多
The Thar Desert,Sindh,Pakistan is characterized by low productivity.Besides,economy is based on agriculture,livestock and mining,nevertheless,livestock graze freely on public and private land.The aim of this research ...The Thar Desert,Sindh,Pakistan is characterized by low productivity.Besides,economy is based on agriculture,livestock and mining,nevertheless,livestock graze freely on public and private land.The aim of this research was to determine biomass production and to evaluate the effects of continuous and seasonal grazing on protected and unprotected plots.A 45 ha protected rangeland area of Hurrabad in the Umerkot Thar desert was selected and divided into three blocks of 15 ha each.Blocks of the same size were also established in unprotected area.The data for vegetation biomass,canopy cover,forage nutrients and weight gain of animals in two seasons(spring and summer)was collected from both protected and unprotected sites.The results showed that biomass significantly increased in summer in both sites.However,the biomass values in protected sites were significantly higher.Similarly,the vegetation cover also seemed to increase in summer in both protected(90.7%±0.29%)and unprotected sites(39.2%±0.09%).The foliar concentrations of all nutrients varied significantly with season.The average final live-weight gain for does on the protected grazing sites during the 42-day period in spring and the 96 days after the monsoon was almost double that of does grazing on the unprotected site during 2016 and 2017(P<0.05).The study concludes that the protection of grazing lands during certain periods can lead to better production of vegetation and livestock and improve range conditions.展开更多
Scrub rangelands support livestock grazing and provide ecosystem services to their inhabitants. The present study was conducted in Chakwal, an important tract of the Pothwar Plateau,which sustains herds of small domes...Scrub rangelands support livestock grazing and provide ecosystem services to their inhabitants. The present study was conducted in Chakwal, an important tract of the Pothwar Plateau,which sustains herds of small domestic and nomadic ruminants. Urbanization and uncontrolled grazing practices have reduced rangeland productivity and increased soil erosion and resulted in poor land conditions. This study assessed the influence of two years of rangeland protection on aboveground vegetation biomass and the chemical composition of plants and aimed to determine the influence of seasonal grazing on the live-weight gain of small ewes.Using the line intercept method, vegetation data from protected and unprotected plots in 2015 and 2016 were collected at two sites, Dhulli and Begal.Vegetation cover was assessed from images using VegMeasure. Results showed that protected study sites displayed higher vegetation biomass(834 and 690 kg ha^(-1)) compared to the unprotected study site(477 and 326 kg ha^(-1)) during April and August of both years. In the seasonal grazing trial, the experimental ewes that grazed on protected rangelands showed higher live-weight gain(33–63 g day^(-1)) compared to live weight of ewes(17–21 g day^(-1)) that grazed on unprotected rangelands during the experimental period of 127 days at both sites. The results suggest that the Chakwal rangeland has tremendous potential to improve vegetation productivity but modern livestock management and seasonal grazing practices are needed to improve carrying capacity and livestock productivity.展开更多
"Ryegrass, orchard grass, Festuca arundinacea and Trifolium repens" were researched in Dushan County, Guizhou Province, in order explore grass characteristics by different grazing methods in seasons. The results sho..."Ryegrass, orchard grass, Festuca arundinacea and Trifolium repens" were researched in Dushan County, Guizhou Province, in order explore grass characteristics by different grazing methods in seasons. The results show that grass community height in different groups was of little differences(P0.05); the group of moderate grazing in spring, summer and autumn dominated in grass cover; grass density showed insignificant variations among different treatment groups(P0.05) and in the groups of heavy grazing in spring and autumn and moderate grazing in summer and of moderate grazing in spring, summer and autumn, grass community density was higher compared with the other groups(P0.05); as for above-ground biomass, the group of moderate grazing in spring and autumn and heavy grazing in summer and of moderate grazing in spring, summer and autumn dominated.展开更多
Aims Management of silvo-pastoral systems in planted and natural forests in semi-arid Mediterranean regions often employs seasonal night corrals for animal protection.This management system changes the spatial distrib...Aims Management of silvo-pastoral systems in planted and natural forests in semi-arid Mediterranean regions often employs seasonal night corrals for animal protection.This management system changes the spatial distribution of animal excreta,resulting in a net transfer of soil mineral resources and their accumulation in the corrals.After abandonment,corrals are colonized by ruderal species,becoming focal sources for their spread in the forest.We aimed to implement a rational management of seasonal sheep corrals based on a better understanding of the vegetation processes occurring in abandoned corrals,in order to alleviate their negative impact in the forest.Methods Relationships between temporal changes in the vegetation,the soil seed-bank and levels of soil nutrients were studied in a chronosequence of abandoned sheep corrals and compared with nearby reference plots in planted Eucalyptus forests grazed by sheep in the semi-arid North-Western Negev,Israel.The region has a bi-seasonal Mediterranean climate,with high dominance of annual species in the grazing range.Important Findings Abandoned sheep corrals were colonized by seeds of ruderals originating in older abandoned corrals.Subsequent successional changes occur at a slow rate,driven by the depletion of soil resources in the abandoned corrals,and were still in progress 20 years after abandonment.Ruderals were gradually replaced,first by taller grasses and followed by short grasses,but most forbs and particularly geophytes did not recover during this period.Recovery of the original herbaceous vegetation in the corrals was through seed dispersal from the surrounding vegetation,not from the original soil seed-bank remaining in the corrals after abandonment.Ruderal species in the grazed,planted forests behave as patch-tracking metapopulations.Their persistency depends on constant creation of new corrals compensating for the gradually dwindling populations in older abandoned corrals,and on the availability of dispersal vectors.展开更多
基金funded by the United States Fish and Wildlife Service and Cleveland MetroPark Zoo
文摘The dynamics of most rangelands in Kenya remain to be poorly understood. This paper provides baseline information on the response of a semiarid rangeland under different livestock grazing regimes on land inhabited by the Massai people in the east side of Amboseli National Park in Kenya. The data were collected from grasslands designated into four types: (1) grassland from previous Massai settlements that had been abandoned for over twenty years; (2) grassland excluded from livestock grazing for eight years; (3) a dry season grazing area; and (4) a continuous grazing area where grazing occurred throughout all seasons. Collected data included grass species composition, grass height, inter-tuft distance, standing grass biomass and soil characteristics. The results indicated that continuous grazing area in semiarid rangelands exhibited loss of vegetation with negative, long-term effects on grass functional qualities and forage production, whereas grassland that used traditional Maasai grazing methods showed efficiency and desirable effects on the rangelands. The results also showed that abandoned homestead sites, though degraded, were important nutrient reservoirs.
基金financial support of the rangeland monitoring trials in the Thar Desertsupport of The International Center for Agricultural Research in the Dry Areas (ICARDA), CRP Livestock and the Livestock and Climate Initiative of the OneCGIAR
文摘The Thar Desert,Sindh,Pakistan is characterized by low productivity.Besides,economy is based on agriculture,livestock and mining,nevertheless,livestock graze freely on public and private land.The aim of this research was to determine biomass production and to evaluate the effects of continuous and seasonal grazing on protected and unprotected plots.A 45 ha protected rangeland area of Hurrabad in the Umerkot Thar desert was selected and divided into three blocks of 15 ha each.Blocks of the same size were also established in unprotected area.The data for vegetation biomass,canopy cover,forage nutrients and weight gain of animals in two seasons(spring and summer)was collected from both protected and unprotected sites.The results showed that biomass significantly increased in summer in both sites.However,the biomass values in protected sites were significantly higher.Similarly,the vegetation cover also seemed to increase in summer in both protected(90.7%±0.29%)and unprotected sites(39.2%±0.09%).The foliar concentrations of all nutrients varied significantly with season.The average final live-weight gain for does on the protected grazing sites during the 42-day period in spring and the 96 days after the monsoon was almost double that of does grazing on the unprotected site during 2016 and 2017(P<0.05).The study concludes that the protection of grazing lands during certain periods can lead to better production of vegetation and livestock and improve range conditions.
基金conducted within the framework of collaborative research between ICARDA and ILRI which was supported by USAID under Agriculture Innovation Program(AIP)Pakistanthe CGIAR Research Program on Livestock Agri-Food Systems。
文摘Scrub rangelands support livestock grazing and provide ecosystem services to their inhabitants. The present study was conducted in Chakwal, an important tract of the Pothwar Plateau,which sustains herds of small domestic and nomadic ruminants. Urbanization and uncontrolled grazing practices have reduced rangeland productivity and increased soil erosion and resulted in poor land conditions. This study assessed the influence of two years of rangeland protection on aboveground vegetation biomass and the chemical composition of plants and aimed to determine the influence of seasonal grazing on the live-weight gain of small ewes.Using the line intercept method, vegetation data from protected and unprotected plots in 2015 and 2016 were collected at two sites, Dhulli and Begal.Vegetation cover was assessed from images using VegMeasure. Results showed that protected study sites displayed higher vegetation biomass(834 and 690 kg ha^(-1)) compared to the unprotected study site(477 and 326 kg ha^(-1)) during April and August of both years. In the seasonal grazing trial, the experimental ewes that grazed on protected rangelands showed higher live-weight gain(33–63 g day^(-1)) compared to live weight of ewes(17–21 g day^(-1)) that grazed on unprotected rangelands during the experimental period of 127 days at both sites. The results suggest that the Chakwal rangeland has tremendous potential to improve vegetation productivity but modern livestock management and seasonal grazing practices are needed to improve carrying capacity and livestock productivity.
基金Supported by Guizhou Academy of Agricultural Sciences Foundation(2010023)Guizhou Academy of Agricultural Sciences Special Funds([2011]021)Guizhou Academy of Agricultural Sciences Foundation for the Talents([2011]01)~~
文摘"Ryegrass, orchard grass, Festuca arundinacea and Trifolium repens" were researched in Dushan County, Guizhou Province, in order explore grass characteristics by different grazing methods in seasons. The results show that grass community height in different groups was of little differences(P0.05); the group of moderate grazing in spring, summer and autumn dominated in grass cover; grass density showed insignificant variations among different treatment groups(P0.05) and in the groups of heavy grazing in spring and autumn and moderate grazing in summer and of moderate grazing in spring, summer and autumn, grass community density was higher compared with the other groups(P0.05); as for above-ground biomass, the group of moderate grazing in spring and autumn and heavy grazing in summer and of moderate grazing in spring, summer and autumn dominated.
基金supported by grants provided by the Israel Ministry of Science and Technology and the Jewish National Fund-KKL.
文摘Aims Management of silvo-pastoral systems in planted and natural forests in semi-arid Mediterranean regions often employs seasonal night corrals for animal protection.This management system changes the spatial distribution of animal excreta,resulting in a net transfer of soil mineral resources and their accumulation in the corrals.After abandonment,corrals are colonized by ruderal species,becoming focal sources for their spread in the forest.We aimed to implement a rational management of seasonal sheep corrals based on a better understanding of the vegetation processes occurring in abandoned corrals,in order to alleviate their negative impact in the forest.Methods Relationships between temporal changes in the vegetation,the soil seed-bank and levels of soil nutrients were studied in a chronosequence of abandoned sheep corrals and compared with nearby reference plots in planted Eucalyptus forests grazed by sheep in the semi-arid North-Western Negev,Israel.The region has a bi-seasonal Mediterranean climate,with high dominance of annual species in the grazing range.Important Findings Abandoned sheep corrals were colonized by seeds of ruderals originating in older abandoned corrals.Subsequent successional changes occur at a slow rate,driven by the depletion of soil resources in the abandoned corrals,and were still in progress 20 years after abandonment.Ruderals were gradually replaced,first by taller grasses and followed by short grasses,but most forbs and particularly geophytes did not recover during this period.Recovery of the original herbaceous vegetation in the corrals was through seed dispersal from the surrounding vegetation,not from the original soil seed-bank remaining in the corrals after abandonment.Ruderal species in the grazed,planted forests behave as patch-tracking metapopulations.Their persistency depends on constant creation of new corrals compensating for the gradually dwindling populations in older abandoned corrals,and on the availability of dispersal vectors.