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Influence of rangeland protection and seasonal grazing on aboveground vegetation,forage quality and weight gain of small ruminants–a study in Thar Desert,Pakistan
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作者 ISLAM Muhammad RAZZAQ Abdul +7 位作者 HASSAN Sawsan ZUBAIR Muhammad KALROO Muhammad Waseem KHAN Attaullah GUL Shamim AHMAD Sarfraz RISCHKOWSKY Barbara Ann LOUHAICHI Mounir 《Journal of Mountain Science》 SCIE CSCD 2023年第2期403-414,共12页
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
关键词 Rangeland productivity Seasonal grazing Stocking rate Thar Desert Vegetation quality
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四川省万源市原产地旧院黑鸡纯系绿壳蛋的分子标记筛选及辅助育种应用 被引量:2
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作者 张丹萍 黎纯 韩建林 《家禽科学》 2022年第4期35-40,共6页
【目的】旨在利用分子标记筛选纯系绿壳蛋旧院黑鸡,为后期组建纯系绿壳蛋旧院黑鸡核心群奠定基础。【方法】通过在1000只旧院黑鸡群体中,应用EAV-HP和ALV的插入整合开展DNA分子标记筛选纯系绿壳蛋旧院黑鸡,通过PCR检测和分析EAV-HP和AL... 【目的】旨在利用分子标记筛选纯系绿壳蛋旧院黑鸡,为后期组建纯系绿壳蛋旧院黑鸡核心群奠定基础。【方法】通过在1000只旧院黑鸡群体中,应用EAV-HP和ALV的插入整合开展DNA分子标记筛选纯系绿壳蛋旧院黑鸡,通过PCR检测和分析EAV-HP和ALV在旧院黑鸡群体中的分布情况,研究绿壳蛋和隐性白羽在旧院黑鸡群体中的基因型频率和基因频率。【结果】在旧院黑鸡群体中检测到了大量的EAV-HP的插入整合,但只存在少量的绿壳蛋纯合子(基因型为LC/LC)个体,占旧院黑鸡群体的15.7%;检测到了少量的ALV的插入整合,无纯合子,只有18个(基因型为N/C、C/C)隐性白羽杂合子,占到整个群体的1.93%。【结论】应用DNA分子标记辅助育种技术,获得了无隐性白羽的纯系绿壳蛋鸡,绿壳蛋率100%。 展开更多
关键词 旧院黑鸡 分子标记 EAV-HP ALV
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Impact of grazing on soil, vegetation and ewe production performances in a semi-arid rangeland 被引量:3
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作者 Muhammad ISLAM Abdul RAZZAQ +6 位作者 Shamim GUL Sarfraz AHMAD Taj MUHAMMAD Sawsan HASSAN Barbara RISCHKOWSKY M.N.M.IBRAHIM Mounir LOUHAICHI 《Journal of Mountain Science》 SCIE CSCD 2018年第4期685-694,共10页
Controlled grazing is considered a good management strategy to maintain or increase the live weight of livestock and to reduce vegetation degradation of rangelands. The present study investigated soil characteristics,... Controlled grazing is considered a good management strategy to maintain or increase the live weight of livestock and to reduce vegetation degradation of rangelands. The present study investigated soil characteristics, aboveground vegetation biomass dynamics and controlled grazinginduced changes in the live weight of local ewes in the semi-arid rangeland of Ahmadun, Ziarat, Balochistanprovince of Pakistan. An area of 115 ha was protected from livestock grazing in April 2014. In June 2015, soil characteristics within 0-30 cm depth i.e. soil organic matter(SOM), mineral nitrogen, p H and texture in controlled and uncontrolled grazing sites were assessed. Aboveground vegetation biomass measured in early(June) and late summer(August) in 2015 and 2016. The nutritional value i.e. crude protein, phosphorus(P), neutral detergent fiber(NDF), acid detergent fiber(ADF), calcium(Ca), magnesium(Mg) and potassium(K) of dominantplant species were assessed at the beginning of experiment in 2015. Vegetation cover of controlled and uncontrolled grazing sites was also measured during the two years of the study period using the Veg Measure software. From June to November in2015 and 2016, controlled and uncontrolled livestock grazing sites were grazed on a daily basis by local ewes with a stocking rate of 2 and 1 head ha^(-1) respectively. Results reveal that the organic matter contents of coarse-textured, slightly alkaline soil of the study site were in the range of 9.4-17.6 g kg^(-1) soil and showed a strong positive correlation with aboveground vegetation biomass. The biomass of plants was 56.5% and 33% greater at controlled than uncontrolled grazing site in 2015 and 2016 respectively and plant cover was also higher at controlled than uncontrolled grazing site in both years The nutrient contents were significantly(P<0.05)lower in grasses than shrubs. In both years, the controlled grazing increased the weight gain of ewes about two folds compared to the uncontrolled grazing.The results indicate that controlled grazing improved the vegetation biomass production and small ruminant productivity. 展开更多
关键词 土壤特征 放牧地 生产率 半干旱 植被 牧场 生物资源 土壤有机物
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Mitochondrial DNA diversity and origin of indigenous pigs in South China and their contribution to western modern pig breeds 被引量:2
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作者 WANG Chen CHEN Yao-sheng +3 位作者 HAN Jian-lin MO De-lin LI Xiu-jin LIU Xiao-hong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第10期2338-2350,共13页
Indigenous pigs in South China are valuable genetic resources with many specific and unique characters, which have played an important role in the establishment of some western modern pig breeds. However, the origin a... Indigenous pigs in South China are valuable genetic resources with many specific and unique characters, which have played an important role in the establishment of some western modern pig breeds. However, the origin and genetic diversity of indigenous pigs in South China have not been fully understood. In the present study, we sequenced 534 novel mitochondrial DNA (mtDNA) D-loop and assembled 54 complete mitogenome sequences for all 17 indigenous pig breeds from Fujian, Guangdong, Guangxi and Hainan in South China. These data were analyzed together with previously published homologous sequences relevant to this study. We found that all 13 coding genes of the mitogenomes were under purifying selection, but ND1 had the most variable sites and CYTB contained the most non-synonymous SNPs. Phylogenetic analysis showed that all indigenous pigs in South China were clustered into the D haplogroup with D1a1, D1b, D1c and D1e sub-haplogroups found to be dominant. Haplotype and nucleotide diversities of D-loop sequences ranged from 0.427 to 0.899 and from 0.00342 to 0.00695, respectively, among which all pigs in Guangdong had the lowest diversity. The estimates of pairwise FST, gene flow (Nm) and genetic distance (Da) indicated that most of these indigenous pig breeds differentiated from each other significantly (P<0.05). Among the western modern breeds, Berkshire and Yorkshire had significant Asian matrilineal footprints from indigenous pigs in South China, especially the Spotted pigs distributed in Guangdong and Guangxi. The neutrality test (Fu’s FS) indicated that indigenous pigs from Fujian and Guangxi had gone through recent population expansion events (P<0.05). It is concluded that indigenous pigs in South China were most likely derived from the Mekong region and the middle and downstream regions of Yangtze River through Guangxi and Fujian. Our findings provide a complete and in-depth insight on the origin and distribution pattern of maternal genetic diversity of indigenous pigs in South China. 展开更多
关键词 PIG South China MITOGENOME D-LOOP genetic DIVERSITY
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Soil fertility effect on water productivity of maize in the upper blue nile basin, Ethiopia 被引量:2
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作者 Teklu Erkossa Seleshi Bekele Awulachew Denekew Aster 《Agricultural Sciences》 2011年第3期238-247,共10页
Maize (Zea mays) is among the major cereals grown in the high rainfall areas of the subSaharan Africa’s (SSA) such as the Ethiopian part of the Blue Nile basin. However, its productivity is severely constrained by po... Maize (Zea mays) is among the major cereals grown in the high rainfall areas of the subSaharan Africa’s (SSA) such as the Ethiopian part of the Blue Nile basin. However, its productivity is severely constrained by poor soil, water and crop management practices. This study simulated the water productivity of the crop under varying soil fertility scenarios (poor, near optimal and none limiting) using hybrid seeds under rainfed conditions using the FAO AquaCrop model. The result indicated that grain yield of maize increased from 2.5 tons.ha–1 under poor to 6.4 and 9.2 tons.ha–1 with near optimal and non-limiting soil fertility conditions. Correspondingly, soil evaporation decreased from 446 mm to 285 and 204 mm, while transpiration increased from 146 to 268 and 355 mm. Consequently, grain water productivity was increased by 48% and 54%, respectively, with the near optimal and non-limiting soil fertility conditions. The water productivity gain mainly comes from reduced evaporation and increased transpiration without significantly affecting water left for downstream ecosystem services. This has a huge implication for a basin scale water management planning for various purposes. 展开更多
关键词 AquaCrop Simulation Water PRODUCTIVITY Soil FERTILITY Nitisols
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旧院黑鸡分子遗传多样性研究进展
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作者 张丹萍 韩建林 +1 位作者 吴震洋 黎纯 《家禽科学》 2021年第1期49-51,57,共4页
旧院黑鸡是四川省地方特色优良品种,被中科院命名为"世界稀有,中国独有,万源特有",具有不可复制性。随着分子遗传学的发展,越来越多的DNA分子水平的研究方法应用在旧院黑鸡的遗传资源挖掘、分子育种、保护及开发等方面,对于... 旧院黑鸡是四川省地方特色优良品种,被中科院命名为"世界稀有,中国独有,万源特有",具有不可复制性。随着分子遗传学的发展,越来越多的DNA分子水平的研究方法应用在旧院黑鸡的遗传资源挖掘、分子育种、保护及开发等方面,对于揭示旧院黑鸡的起源、进化和种质特性,挖掘旧院黑鸡品种本身存在的优良价值和特色性状基因,培育特色、优质新品种和配套系等具有重要意义。 展开更多
关键词 旧院黑鸡 分子遗传多样性 研究进展
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Performance of Smallholder Dairy Farming in Nakuru County, Kenya
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作者 Dennis Kinambuga Benjamin K. Mutai +2 位作者 George Owuor Aquilars M. Kalio Emmanuel K. Kinuthia 《Journal of Agricultural Science and Technology(A)》 2012年第4期481-488,共8页
关键词 奶牛养殖 小规模 肯尼亚 盈利能力 性能 数据包络分析 测量单位 多阶段抽样
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Begait Goat Production Systems and Breeding Practices in Western Tigray, North Ethiopia
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作者 Hagos Abraham Solomon Gizaw Mengistu Urge 《Open Journal of Animal Sciences》 2017年第2期198-212,共15页
A study was undertaken to characterize production system, breeding practices and production constraints of Begait goat in Kafta humera district, northwestern lowlands of Ethiopia. Personal observations, focus group di... A study was undertaken to characterize production system, breeding practices and production constraints of Begait goat in Kafta humera district, northwestern lowlands of Ethiopia. Personal observations, focus group discussions and a detailed structured questionnaire were used to collect data from 150 respondents (99 small-scale and 51 large-scale farmers). Mixed crop-livestock production system was found to be the dominant farming system in the study district. The farmers kept a variety of livestock species including goats, sheep, cattle, chickens and donkeys. Small ruminants are the most numerous and are of great importance in the area. Goats are herded with sheep in the open fields by the young boys in the family/hired grazers. They have a number of roles though mainly kept as a source of cash income. Breeding was generally uncontrolled. Size, growth rate and libido were the most frequently reported traits in selecting bucks, whereas does were selected based on size, twining ability and milk yield. Effective population size and rate of inbreeding were calculated by considering random mating and flocks were not mixed. The major constraints hampering goat production in the area were water scarcity, feed and grazing land shortages and insufficient veterinary services among the others. Therefore, addressing these constraints is important to design a successful genetic improvement scheme in the area for goat. 展开更多
关键词 FARMING System HUSBANDRY Practice MARKETING Production Constraints
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Factors Affecting Arab Goat Flock Dynamics in Western Lowlands of Ethiopia
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作者 Befikadu Zewdie Mengistu Urge +1 位作者 Yosef Tadesse Solomon Gizaw 《Open Journal of Animal Sciences》 2019年第3期305-323,共19页
The study was conducted to estimate flock dynamics of western lowland Arab goat and to assess their contribution to income of smallholder farmers in Kurmuk and Assosa districts, western Ethiopia. Flocks of 30 househol... The study was conducted to estimate flock dynamics of western lowland Arab goat and to assess their contribution to income of smallholder farmers in Kurmuk and Assosa districts, western Ethiopia. Flocks of 30 households were monitored for a period of 12 months in 2016. Data were analyzed using the general linear model procedure of SAS and two-way interaction effects were fitted in the model and retained when found significant in the preliminary analysis. The study result indicates that total entrances for all flock were significantly (p < 0.05) higher in dry and hot-cool seasons than wet season. Most of the entrance was kids born in hot-cool season (January) (4.0 ± 0.42) and hot-dry season (May) (5.4 ± 1.09) for Assosa and Kumruk study sites, respectively. Kid mortality constituted the greater part of outflow. High kid mortality was occurred during July, February, January, and September. Most of the sell of castrated goats were occurred in September and April for both small and large flocks targeting holidays celebrated during this months. Male goat owners had significantly lower goat production potential (GPP) value than female (0.47 ± 0.02 vs. 0.52 ± 0.02). The GPP was lower in small flock than in large flock (0.48 ± 0.02 vs. 0.51 ± 0.02). Higher GPP was recorded in the months of January, February, and March for both large and small flocks. The off-take was higher (P < 0.05) in Assosa (0.06 ± 0.01) than Kumruk (0.02 ± 0.02) district. The average goat production efficiency (GPE) was higher (P < 0.05) in Assosa large (193.23 ± 20.0) and small flocks (93.44 ± 17.3) than Kumruk large (84.71 ± 15.6) and small flocks (33.33 ± 26.3).The production efficiency recorded was not comparable to the potential that the farmers had to sell goats or consume goats’ meat and milk. The lower goat production potential observed for small flocks implies that high mortality rates severely restrict receiving higher benefits from goat. Therefore, in order to optimize the productivity of goats flock dynamics, developing health intervention strategies that target reduction of kids’ mortality is imperative. 展开更多
关键词 ENTRANCE EXIT GOAT Off-Take PRODUCTION Efficiency PRODUCTION Potential
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Nitrogen fertilization effects on grain quality of durum wheat (<i>Triticum turgidum</i>L. var. durum) varieties in central Ethiopia
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作者 Leta Gerba Belay Getachew Worku Walelign 《Agricultural Sciences》 2013年第3期123-130,共8页
Four released durum wheat varieties, two medium tall (Arsi-Robe and Kilinto) and two recently released semidwarfs (Ude and Yerer) were evaluated under five different N rates (0, 60, 120, 180 and 240 kg·ha-1) in 2... Four released durum wheat varieties, two medium tall (Arsi-Robe and Kilinto) and two recently released semidwarfs (Ude and Yerer) were evaluated under five different N rates (0, 60, 120, 180 and 240 kg·ha-1) in 2005/06 growing season at Akaki and Debre Zeit, central Ethiopia. The quality responses of durum wheat varieties to different N-fertilizer rates and the N responses between tall and short durum wheat varieties were assessed. Protein and gluten content, vitreous kernel count, thousand kernel weight, test weight and lodging were considered. Vitreous kernel count, protein and gluten content were higher at Debre Zeit than at Akaki. Unlike Debre Zeit, there were significant relationships between response variables and fertilizer levels at Akaki. Lodging slightly affected the medium tall varieties at Debre Zeit whereas it was not a problem at Akaki. At Akaki, varieties response to each additional N rate was entirely below the quality standard set by ICC, 2000 except for thousandkernel weight. Therefore, it is unwise to promote durum wheat scaling up/out program for quality production at Akaki. 展开更多
关键词 Gluten CONTENT N-FERTILIZATION Protein CONTENT Thousand KERNEL WEIGHT Test WEIGHT Vitreous KERNEL Count
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Genotypic Variation for Low Striga Germination Stimulation in Sorghum “Sorghum bicolor (L.) Moench” Landraces from Eritrea
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作者 Tadesse Yohannes Kahiu Ngugi +4 位作者 Emanuel Ariga Tesfamichael Abraha Nasser Yao Pauline Asami Monday Ahonsi 《American Journal of Plant Sciences》 2016年第17期2470-2482,共13页
Sorghum (Sorghum bicolour (L.) Moench), the second most important staple crop in Sub-Saharan Africa (SSA) after maize, is well adapted to marginal environments of drought stress and high temperatures. But besides drou... Sorghum (Sorghum bicolour (L.) Moench), the second most important staple crop in Sub-Saharan Africa (SSA) after maize, is well adapted to marginal environments of drought stress and high temperatures. But besides drought stress, the obligate root-parasitic flowering plant Striga hermonthica is an equally economically important biotic stress in agro-ecological zones where soils are marginal. Notwithstanding widespread and intense Striga infestation, genetic variations in defence mechanisms against the parasite have been reported. Sorghum variants, producing low levels of chemical stimulants such as sorgolactones that deter the advance of Striga seed germination and are therefore deemed resistant to the parasite, have been also reported in a few studies. But the existence of sorghum genetic variation for this resistance especially among farmers’ landraces is yet to be demonstrated. The objective of this study was therefore to determine the levels of Striga germination stimulants in response to each of the 111 collected sorghum landraces and their progenies from Eritrea. The ability of a sorghum genotype to cause germination of a Striga seed as a measure of the amount of the germination stimulant produced was used to assess the resistance of these accessions. The data were recorded as Striga germination percentage by counting the number of germinated Striga seeds. Landraces EG47, EG1261, EG830, EG1076, EG54 and EG746 with 14.68%, 15.32%, 11.85%, 13.05%, 15.74% and 16.5% germination percentages respectively were found to stimulate low levels of Striga germination percentage compared to commercial checks, IS9830, SRN39, Framida, with 22.46%, 22.67%, 23.27% germination respectively. While these variants did not show complete resistance against Striga seed germination, the low level production of stimulant indicated their high level of resistance to Striga . These results implied that these accessions are likely potential sources of resistance against Striga infestation in SSA sorghum breeding programs. 展开更多
关键词 ERITREA Landrace Sorghum Striga hermonthica Striga Germination Stimulants Seed Parasitic Plants
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Effects of Mulching Material on the Early Fruit Yield of Tomato (Lycopersicon esculentum Mill.) Varieties under Polyhouse Growing Condition
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作者 Habtamu Tegen Yigzaw Dessalegn Wasu Mohammed 《Journal of Agricultural Science and Technology(B)》 2014年第8期612-620,共9页
关键词 番茄品种 前期产量 生长条件 膜材料 果实成熟度 覆盖材料 早果 大棚
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Source of mycorrhizal inoculum influences growth of Faidherbia albida seedlings
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作者 Emiru Birhane Mengsteab Hailemariam +3 位作者 Girmay Gebresamuel Tesfay Araya Kiros Meles Hadgu Lindsey Norgrove 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第1期313-323,共11页
Poor land use management and practice inhibit the growth and establishment of tree seedlings in dryland areas.We assessed arbuscular mycorrhizal fungi(AM)status of Faidherbia albida(Del.)A.Chev.trees grown on differen... Poor land use management and practice inhibit the growth and establishment of tree seedlings in dryland areas.We assessed arbuscular mycorrhizal fungi(AM)status of Faidherbia albida(Del.)A.Chev.trees grown on different land uses.We quantified the growth and nutrient uptake of F.albida seedlings inoculated with AM from different sources.These efforts were based on soil and fine root samples from the rhizosphere soils of F.albida trees.AM root colonization was determined using the gridline intersect method.Spores were extracted by the wet sieving and decanting method and identified to genus level.The seedling experiment had a completely randomized onefactorial design with four treatments and five replications.Faidherbida albida seedlings were grown in a greenhouse.All in situ F.albida trees were colonized by AM fungi.AM root colonization of F.albida trees was significantly higher(P<0.0086)in area exclosures than on lands used for grazing or cultivation.Spore abundance was significantly higher(P<0.0014)in area exclosures followed by cultivated land and grazing land.Glomus was the dominant genus in all land-uses.AM-inoculated F.albida seedlings grew better(P<0.05)than non-inoculated controls.Seedlings inoculated with AM from area exclosure had significantly(P<0.05)higher growth and nutrient uptake than those inoculated with AM from grazing and cultivated land.This emphasizes the importance of the native soil AM potential for better establishment of seedlings to achieve optimum plant growth improvement and assist in rehabilitation of degraded arid lands. 展开更多
关键词 Spore abundance AM colonization Inoculum types Land-use types Nutrient uptake Growth parameters
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Production Systems, Genetic Diversity and Genes Associated with Prolificacy and Milk Production in Indigenous Goats of Sub-Saharan Africa: A Review
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作者 Simon Patrick Baenyi Joseph Owino Junga +4 位作者 Christian Keambou Tiambo Ahadi Bwihangane Birindwa Katcho Karume Getinet Mekuriaw Tarekegn Joel Winyo Ochieng 《Open Journal of Animal Sciences》 2020年第4期735-749,共15页
Goats are one of the oldest domesticated animal species widely distributed in the world playing an important role in the food production system in Sub-Saharan African Region (SSAR). Due to their multiple uses (milk pr... Goats are one of the oldest domesticated animal species widely distributed in the world playing an important role in the food production system in Sub-Saharan African Region (SSAR). Due to their multiple uses (milk production, meat, fiber and hides) and adaptation aptitudes to ecological conditions, goats produce and contribute positively to farmers’ socio-economy status in various production systems. This review aimed at giving a summary overview on the goat’s production systems characteristics, the genetic diversity and the candidate genes affecting reproductive and milk production performances in goat breeds in SSAR. It has been observed that traditional livestock production system with communal grazing system is the most used in goat keeping in SSAR. The geographical locations play an important role in the relationships between goat’s distributions in the region. At the same time, goats might have been differentiated and isolated one to others due to the wide geographic range, the diversify climate and the topography in the region. Among the six worldwide known haplogroups of goat (A, B, C, D, G and F), haplogroup A is the most representative in SSAR. However, haplogroup G and B can be found in some goat populations in some countries in east (Kenya and Ethiopia) and south parts of Africa. This review reveals that little is known on the candidate genes associated with prolificacy and milk production traits in indigenous goat breeds in the region. That observation suggests the importance of assessing candidate genes associated with economic traits in the populations of goat in SSAR. 展开更多
关键词 GENE PROLIFICACY Milk Production Sub-Saharan African Region
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Observed and Future Spatiotemporal Changes of Rainfall Extreme Characteristics and Their Dynamic Driver in June-August Season over Africa
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作者 Asaminew Teshome Jie Zhang +1 位作者 Teferi Demissie Qianrong Ma 《Atmospheric and Climate Sciences》 2022年第2期358-382,共25页
Climate change has increased extreme events over globe and the most robust occurrences of concurrent drought and floods have become more common in Africa. This study focuses on the observed and projected analysis of r... Climate change has increased extreme events over globe and the most robust occurrences of concurrent drought and floods have become more common in Africa. This study focuses on the observed and projected analysis of rainfall extremes of consecutive dry day (CDD) and maximum monthly five day precipitation (RX5day) from Expert Team on Climate Change Detection and Indices (ETCCDI) in June-August season over Africa. The daily CORDEX Africa, reanalysis and CRU datasets were analyzed for extreme trends under RCP4.5 and RCP8.5 scenarios for the periods of 1980 to 2100. The spatiotemporal variability, trend, and magnitude of JJA seasonal rainfall performance exhibits a significant decreasing tendency over Eastern Africa compared to West Africa. The observed results of consecutive dry day (CDD) reveal that increasing trend and moreover RX5day shows that promising positive trend. Both rainfall extremes are influenced by the combined effect of large scale indexes and appear to be correlated negatively and positively with ENSO, NAO and AO. The CORDEX ensemble mean projections of JJA seasonal rainfall performance show a widespread significant change and the first mode of EOF depicts that 13.8% and 24.9% under the RCP4.5 and the highest variability is under RCP8.5 scenario. The projected CDD extreme exhibit an increasing trend in the coming periods and the percentage change revealed that increasing from 25.11%, 28.02% over West and 26.49%, 31.66% East Africa under RCP4.5 and RCP8.5 scenarios respectively. This situation will exacerbate increasing of frequent and intensified drought extremes over Africa. Additionally, the future RX5day indicated that mixed trend and revealed that increasing 3.72%, 2.54% over West and decreases -16.12%, -22.47% over East Africa under RCP4.5 and RCP8.5 respectively. Generally, rainfall extremes of CDD are projected to increase and RX5day shows a mixed trend in the coming periods over Africa and calls for further verification by using high resolution datasets. 展开更多
关键词 AFRICA EXTREMES JJA OBSERVED Projected
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Impact of rangeland enclosure and seasonal grazing on protected and unprotected rangelands in Chakwal region, Pakistan
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作者 ISLAM Muhammad RAZZAQ Abdul +5 位作者 ZUBAIR Muhammad HASSAN Sawsan AHMAD Sarfraz GUL Shamim RISCHKOWSKY Barbara LOUHAICHI Mounir 《Journal of Mountain Science》 SCIE CSCD 2022年第1期46-57,共12页
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
关键词 Seasonal grazing Climate change PRODUCTIVITY RANGELAND Protected area
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Erratum to:Impact of rangeland enclosure and seasonal grazing on protected and unprotected rangelands in Chakwal region,Pakistan
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作者 ISLAM Muhammad RAZZAQ Abdul +5 位作者 ZUBAIR Muhammad HASSAN Sawsan AHMAD Sarfraz GUL Shamim RISCHKOWSKY Barbara LOUHAICHI Mounir 《Journal of Mountain Science》 SCIE CSCD 2022年第4期1215-1216,共2页
Erratum to:J.Mt.Sci.(2022)19(1):46-57 https://doi.org/10.1007/s11629-021-6761-z The article“Impact of rangeland enclosure and seasonal grazing on protected and unprotected rangelands in Chakwal region,Pakistan”,writ... Erratum to:J.Mt.Sci.(2022)19(1):46-57 https://doi.org/10.1007/s11629-021-6761-z The article“Impact of rangeland enclosure and seasonal grazing on protected and unprotected rangelands in Chakwal region,Pakistan”,written by ISLAM Muhammad,RAZZAQ Abdul,ZUBAIR Muhammad,HASSAN Sawsan,AHMAD Sarfraz,GUL Shamim,RISCHKOWSKY Barbara and LOUHAICHI Mounir. 展开更多
关键词 protected IMPACT SEASONAL
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Root symbioses as belowground C pumps:a mitigation strategy against rising CO_(2)levels
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作者 Peter E.Mortimer James Hammond +2 位作者 Kevin D.Hyde Heng Gui Jianchu Xu 《Circular Agricultural Systems》 2021年第1期62-64,共3页
Mycorrhizal and N-fixing root symbioses evolved at two points in the past when global CO_(2)was highest,consistent with the high demand these symbioses place on host C.Trees hosting both mycorrhiza and N-fixing bacter... Mycorrhizal and N-fixing root symbioses evolved at two points in the past when global CO_(2)was highest,consistent with the high demand these symbioses place on host C.Trees hosting both mycorrhiza and N-fixing bacteria are able to fix more atmospheric CO_(2)and grow at faster rates than non-symbiotic plants,or plants with only mycorrhiza.We argue that on the basis of this improved C capture,N-fixing trees act as C-pumps,sequestering C and locking it in biomass,thus,if properly managed,can contribute significantly towards the mitigation of rising CO_(2)levels. 展开更多
关键词 ROOT (2) PROPERLY
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ABE-induced PDGFD start codon silencing unveils new insights into the genetic architecture of sheep fat tails
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作者 Peter Kalds Shuhong Huang +16 位作者 Shiwei Zhou Siyuan Xi Yumeng Fang Yawei Gao Kexin Sun Chao Li Bei Cai Yao Liu Yige Ding Qifang Kou Tad Sonstegard Bjöm Petersen Stephen Kemp Baohua Ma Jian-Lin Han Yulin Chen Xiaolong Wang 《Journal of Genetics and Genomics》 SCIE CSCD 2023年第12期1022-1025,共4页
Sheep is an important livestock species raised globally to produce meat,milk,wool,and other by-products.During the Neolithic Revolution,sheep were domesticated in the Fertile Crescent of Southwest Asia around 10,000 y... Sheep is an important livestock species raised globally to produce meat,milk,wool,and other by-products.During the Neolithic Revolution,sheep were domesticated in the Fertile Crescent of Southwest Asia around 10,000 years ago(Chessa et al.,2009). 展开更多
关键词 products. globally raised
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Global dispersal and adaptive evolution of domestic cattle:a genomic perspective
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作者 Xiaoting Xia Kaixing Qu +8 位作者 Yan Wang Mikkel-Holger SSinding Fuwen Wang Quratulain Hanif Zulfiqar Ahmed Johannes A.Lenstra Jianlin Han Chuzhao Lei Ningbo Chen 《Stress Biology》 2023年第1期98-110,共13页
Domestic cattle have spread across the globe and inhabit variable and unpredictable environments.They have been exposed to a plethora of selective pressures and have adapted to a variety of local ecological and manage... Domestic cattle have spread across the globe and inhabit variable and unpredictable environments.They have been exposed to a plethora of selective pressures and have adapted to a variety of local ecological and management conditions,including UV exposure,diseases,and stall-feeding systems.These selective pressures have resulted in unique and important phenotypic and genetic differences among modern cattle breeds/populations.Ongoing efforts to sequence the genomes of local and commercial cattle breeds/populations,along with the growing availability of ancient bovid DNA data,have significantly advanced our understanding of the genomic architecture,recent evolution of complex traits,common diseases,and local adaptation in cattle.Here,we review the origin and spread of domestic cattle and illustrate the environmental adaptations of local cattle breeds/populations. 展开更多
关键词 CATTLE ORIGIN DOMESTICATION Migration route Environmental adaptation Selective pressure
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