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Grassland Pasture Composition and Quality in the Communes of Ziguinchor and Kolda, Senegal
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作者 Aly Diallo Saboury Ndiaye +4 位作者 Arfang Ousmane Kemo Goudiaby Yaya Diatta Mamadou Ndao Mamadou Diamanka Gnima Manga 《Open Journal of Ecology》 2024年第9期683-705,共23页
In Senegal, natural pasture plays a major role in feeding livestock. During the rainy season, herbaceous plants account for a large proportion of the fodder consumed by ruminants. In Casamance, the composition and qua... In Senegal, natural pasture plays a major role in feeding livestock. During the rainy season, herbaceous plants account for a large proportion of the fodder consumed by ruminants. In Casamance, the composition and quality of these grasses are poorly known and underexploited. In this context, the study aimed to improve the knowledge and valorisation of the herbaceous fodder of the South. Individual interviews were conducted and a questionnaire was sent to farmers living in Ziguinchor and Kolda. A floristic inventory with a phytosociological approach was also carried out. The data collected were processed using Excel and Sphinx software in order to differentiate and classify the herbaceous species eaten by the tail. The majority of respondents were Fulani (55.30%). most of whom ranged in age from 30 to 60. Livestock rearing came second (38.3%) after agriculture (40%) among the principal activities of the people surveyed. The floristic inventory identified 95 species in 68 genera and 22 families. Species of low and medium pastoral value dominate the herbaceous layer. The global rangeland quality index was 48.16% and the brute pastoral value was 54.77%. Thirteen species contributed 54.86% of the pastoral value of the grassland. The floristic composition of community rangelands showed the presence of a varied herbaceous fodder range. The combination of which will help to develop a table of nutritional values for the formation of equilibrated feed rations for farmed livestock. 展开更多
关键词 FODDER HERBACEOUS pasture Nutritional Assessment LIVESTOCK
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Spatio-Temporal Variability of Rainfall and Temperature and Their Effects on Pasture Variability over East Africa: Implication on the Cattle Grazing Areas
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作者 Natiko Peter Wang Wen +2 位作者 Nyasulu Matthews Raharivelo Sitraka Ny Aina Alupot Donnata 《Journal of Geoscience and Environment Protection》 2024年第3期54-69,共16页
Understanding the spatiotemporal variability of climatic parameters and their effects on pasture variability is vital for pasture management interventions over East Africa. The present study aims to assess the spatial... Understanding the spatiotemporal variability of climatic parameters and their effects on pasture variability is vital for pasture management interventions over East Africa. The present study aims to assess the spatial-temporal variability of rainfall, temperature and Normalized Difference Vegetation Index (NDVI) (which is being used to assess pasture quality and productivity) over the region, between the period of 1982 and 2019. This study used annual mean values for rainfall, temperature and NDVI which were calculated for the period mentioned above. NDVI was derived from National Oceanic and Atmospheric Administration (NOAA) Global Area Cover (GAC) (NOAA-07-GAC) data. The rainfall data was acquired from the Climate Hazards Group Infrared Precipitation with Station (CHIRPS) while temperature is ERA5 reanalysis data sourced from the European Centre for Medium-Range Weather Forecasts (ECMWF). The study utilized the empirical orthogonal function (EOF) to identify patterns and dominant relationships between the climate variables. The correlation was calculated between rainfall, temperature and NDVI to assess the relationship among them. A non-parametric Mann-Kendall trends test was used to determine whether annual precipitation, temperature and NDVI had statistically increasing or decreasing trend. Results revealed a positive correlation between rainfall and NDVI while a negative correlation between NDVI and temperature. Positive correlation between rainfall and NDVI indicates that pasture health (quality and productivity), will improve accordingly. A negative correlation between temperature and NDVI indicates that pasture health will decrease with increase in temperature while improving with decreasing temperature. Outcome from this study suggests that changes in climatic variables influence the distribution of pasture in East Africa’s cattle grazing areas. The study hence recommends prioritisation of climatic (weather) information during pasture management over East Africa. 展开更多
关键词 NDVI Climatic Parameters EOF pasture East Africa
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纪念世界第一本RANGE AND PASTURE MANAGEMENT(《草原与放牧地管理学》)教材出版100周年
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作者 胡自治 《草原与草坪》 CAS CSCD 2023年第5期1-4,共4页
1923年,美国第一本,也是世界第一本草原管理学方面的教材——RANGE AND PASTURE MANAGEMENT(《草原与放牧地管理学》)出版。本文通过对该书的作者、内容(前言、正文和索引)、对美国草原管理学教育和教材的重要影响、对我国草原管理学同... 1923年,美国第一本,也是世界第一本草原管理学方面的教材——RANGE AND PASTURE MANAGEMENT(《草原与放牧地管理学》)出版。本文通过对该书的作者、内容(前言、正文和索引)、对美国草原管理学教育和教材的重要影响、对我国草原管理学同类教材建设的意义进行介绍和论述,以纪念该书出版100周年。 展开更多
关键词 RANGE AND pasture MANAGEMENT(《草原与放牧地管理学》) 桑普森(Arthur W Sampson) 纪念
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Changes in climatic conditions drive variations in arbuscular mycorrhizal fungi diversity and composition in semi-arid oak forests
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作者 Nahid Jafarian Javad Mirzaei +1 位作者 Reza Omidipour Yahya Kooch 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期106-119,共14页
Arbuscular mycorrhizal fungi(AMF)play a vital role in plant productivity and ecosystem functions.However,their responses to abiotic factors(i.e.,climate,physiography,and soil properties)are unknown,especially across c... Arbuscular mycorrhizal fungi(AMF)play a vital role in plant productivity and ecosystem functions.However,their responses to abiotic factors(i.e.,climate,physiography,and soil properties)are unknown,especially across climatic gradients and slope aspects in arid and semi-arid ecosys-tems.In this study,using 60 composite soil samples,direct and indirect effects of climate factors and slope aspects on AMF diversity,composition and spore density were studied.The findings indicate that climate has a more direct influ-ence on soil properties(P<0.001)in comparison to slope aspect(P=0.449).In contrast,climate significantly affected AMF diversity and composition,with the highest diversity in dryer areas.Soil pH had the highest correlation with different facets of AMF diversity.Structural equation modeling(SEM)indicated that only a small part of the variation in AMF diversity and spore density could be explained by climate characteristics,slope aspect and soil properties.Based on SEM results,climate was the most important determinant of AMF diversity and spore density;slope aspect had a less critical role.The outputs suggest that variations in AMF diversity are derived by the direct effects of climate and the indirect effect of soil chemical properties.In addition,with increasing dryness,sporulation and AMF diversity increased. 展开更多
关键词 AMF diversity and composition Physiographic factors semi-arid ecosystems Zagros forest
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Scale dependence of forest fragmentation and its climate sensitivity in a semi-arid mountain:Comparing Landsat,Sentinel and Google Earth data
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作者 Yuyang Xie Jitang Li +2 位作者 Tuya Wulan Yu Zheng Zehao Shen 《Geography and Sustainability》 CSCD 2024年第2期200-210,共11页
Landscape fragmentation is generally viewed as an indicator of environmental stresses or risks,but the fragmentation intensity assessment also depends on the scale of data and the definition of spatial unit.This study... Landscape fragmentation is generally viewed as an indicator of environmental stresses or risks,but the fragmentation intensity assessment also depends on the scale of data and the definition of spatial unit.This study aimed to explore the scale-dependence of forest fragmentation intensity along a moisture gradient in Yinshan Mountain of North China,and to estimate environmental sensitivity of forest fragmentation in this semi-arid landscape.We developed an automatic classification algorithm using simple linear iterative clustering(SLIC)and Gaussian mixture model(GMM),and extracted tree canopy patches from Google Earth images(GEI),with an accuracy of 89.2%in the study area.Then we convert the tree canopy patches to forest category according to definition of forest that tree density greater than 10%,and compared it with forest categories from global land use datasets,FROM-GLC10 and GlobeLand30,with spatial resolutions of 10 m and 30 m,respectively.We found that the FROM-GLC10 and GlobeLand30 datasets underestimated the forest area in Yinshan Mountain by 16.88%and 21.06%,respectively;and the ratio of open forest(OF,10%<tree coverage<40%)to closed forest(CF,tree coverage>40%)areas in the underestimated part was 2:1.The underestimations concentrated in warmer and drier areas occupied mostly by large coverage of OFs with severely fragmented canopies.Fragmentation intensity of canopies positively correlated with spring temperature while negatively correlated with summer precipitation and terrain slope.When summer precipitation was less than 300 mm or spring temperature higher than 4℃,canopy fragmentation intensity rose drastically,while the forest area percentage kept stable.Our study suggested that the spatial configuration,e.g.,sparseness,is more sensitive to drought stress than area percentage.This highlights the importance of data resolution and proper fragmentation measurements for forest patterns and environmental interpretation,which is the base of reliable ecosystem predictions with regard to the future climate scenarios. 展开更多
关键词 Tree canopy fragmentation Forest coverage Google Earth images Spatial Scale effect semi-arid mountains
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Estimating the Drought-Induced Yield Loss for Winter Wheat in a Semi-Arid Region of the Southern United States Using a Drought Index
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作者 Prem Woli Qingwu Xue +2 位作者 Gerald R. Smith Charles R. Long Francis M. Rouquette Jr. 《Agricultural Sciences》 2024年第8期812-829,共18页
The economy of most rural locations in the semi-arid region of Llano Estacado in the southern United States is predominantly based on agriculture, primarily beef and wheat (Triticum aestivum L.) production. This regio... The economy of most rural locations in the semi-arid region of Llano Estacado in the southern United States is predominantly based on agriculture, primarily beef and wheat (Triticum aestivum L.) production. This region is prone to drought and is projected to experience a drier climate. Droughts that coincide with the critical phenological phases of a crop can be remarkably costly. Although drought cannot be prevented, its losses can be minimized through mitigation measures if it is predicted in advance. Predicting yield loss from an imminent drought is an important need of stakeholders. One way to fulfill this need is using an agricultural drought index, such as the Agricultural Reference Index for Drought (ARID). Being plant physiology-based, ARID can represent drought-yield relationships accurately. This study developed an ARID-based yield model for predicting the drought-induced yield loss for winter wheat in this region by accounting for its phenological phase-specific sensitivity to water stress. The reasonable values of the drought sensitivity coefficients of the yield model indicated that it could reflect the phenomenon of water stress decreasing the winter wheat yields in this region reasonably. The values of the various metrics used to evaluate the model, including Willmott Index (0.86), Nash-Sutcliffe Index (0.61), and percentage error (26), indicated that the yield model performed fairly well at predicting the drought-induced yield loss for winter wheat. The yield model may be useful for predicting the drought-induced yield loss for winter wheat in the study region and scheduling irrigation allocation based on phenological phase-specific drought sensitivity. 展开更多
关键词 ARID DROUGHT Drought index Growth-stage Model Phenological-Phase Prediction semi-arid Wheat Yield
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Spatio-temporal variation of depth to groundwater level and its driving factors in arid and semi-arid regions of India
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作者 Suchitra PANDEY Geetilaxmi MOHAPATRA Rahul ARORA 《Regional Sustainability》 2024年第2期103-122,共20页
Climate change and increasing anthropogenic activities,such as over-exploitation of groundwater,are exerting unavoidable stress on groundwater resources.This study investigated the spatio-temporal variation of depth t... Climate change and increasing anthropogenic activities,such as over-exploitation of groundwater,are exerting unavoidable stress on groundwater resources.This study investigated the spatio-temporal variation of depth to groundwater level(DGWL)and the impacts of climatic(precipitation,maximum temperature,and minimum temperature)and anthropogenic(gross district product(GDP),population,and net irrigated area(NIA))variables on DGWL during 1994-2020.The study considered DGWL in 113 observation wells and piezometers located in arid western plains(Barmer and Jodhpur districts)and semi-arid eastern plains(Jaipur,Ajmer,Dausa,and Tonk districts)of Rajasthan State,India.Statistical methods were employed to examine the annual and seasonal patterns of DGWL,and the generalized additive model(GAM)was used to determine the impacts of climatic and anthropogenic variables on DGWL.During 1994-2020,except for Barmer District,where the mean annual DGWL was almost constant(around 26.50 m),all other districts exhibited increase in DGWL,with Ajmer District experiencing the most increase.The results also revealed that 36 observation wells and piezometers showed a statistically significant annual increasing trend in DGWL and 34 observation wells and piezometers exhibited a statistically significant decreasing trend in DGWL.Similarly,32 observation wells and piezometers showed an statistically significant increasing trend and 37 observation wells and piezometers showed a statistically significant decreasing trend in winter;33 observation wells and piezometers indicated a statistically significant increasing trend and 34 had a statistically significant decreasing trend in post-monsoon;35 observation wells and piezometers exhibited a statistically significant increasing trend and 32 observation wells and piezometers showed a statistically significant decreasing trend in pre-monsoon;and 36 observation wells and piezometers reflected a statistically significant increasing trend and 30 observation wells and piezometers reflected a statistically significant decreasing trend in monsoon.Interestingly,most of the observation wells and piezometers with increasing trends of DGWL were located in Dausa and Jaipur districts.Furthermore,the GAM analysis revealed that climatic variables,such as precipitation,significantly affected DGWL in Barmer District,and DGWL in all other districts was influenced by anthropogenic variables,including GDP,NIA,and population.As a result,stringent regulations should be implemented to curb excessive groundwater extraction,manage agricultural water demand,initiate proactive aquifer recharge programs,and strengthen sustainable management in these water-scarce regions. 展开更多
关键词 Climate change Generalized additive model(GAM) Depth to groundwater level(DGWL) Climatic and anthropogenic variables Arid and semi-arid regions
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Conversion of cropland into agroforestry land versus naturally-restored grassland alters soil macro-faunal diversity and trophic structure in the semi-arid agro-pasture zone of northern China
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作者 LIU Rentao Yosef STEINBERGER +5 位作者 HOU Jingwei ZHAO Juan LIU Jianan CHANG Haitao ZHANG Jing LUO Yaxi 《Journal of Arid Land》 SCIE CSCD 2019年第2期306-317,共12页
Restoration of cropland(termed 'Farm') after abandonment including shrubs(termed 'Shrub'),trees(termed 'Tree') and natural grassland(termed 'Grass') has become a routine process aimed t... Restoration of cropland(termed 'Farm') after abandonment including shrubs(termed 'Shrub'),trees(termed 'Tree') and natural grassland(termed 'Grass') has become a routine process aimed to improve land productivity and control desertification. During this restoration process, soil macro-faunal diversity, and trophic structure were investigated at four types of sites(Farm, Shrub, Tree, and Grass)during growing season in the semi-arid agro-pasture zone of northern China. Results indicated that the Staphylinidae family was found to dominate at the Grass, Shrub, and Tree sites, whiles larval Pyralidae individuals were found at the Grass site only. The density of the omnivores(i.e., Formicidae family) was significantly(P<0.05) greater at the Grass site than at the Tree and Farm sites. The total density and richness of predator and phytophages were found to be markedly(P<0.05) greater at the Grass site than at the Farm site. Meanwhile, we found the taxon richness of predators was significantly(P<0.05) higher at the Shrub site than at the Farm and Tree sites. Compared with the Farm and afforested Shrub/Tree sites,the Grass site had greater density, taxon richness, and Shannon index(P<0.05). In conclusion, natural restoration of abandoned croplands toward grassland was an effective strategy relative to artificial afforestation for improvement of soil biological diversity. Moreover, planting shrub is a preferable measure in abandoned croplands for land development in the semi-arid agro-pasture zone of northern China. 展开更多
关键词 abandoned CROPLAND agro-pasture ZONE community DIVERSITY LAND restoration SOIL macrofauna
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Effect of thatch on water-soluble phosphorus of pasture soil fertilized with broiler litter
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作者 陈欣 张庆忠 M.L.Cabrera 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期71-73,共3页
The presence of a thatch layer in established pastures could reduce the contact between broiler litter and soil, thus increasing the potential for surface runoff contamination with litter P. We conducted a laboratory ... The presence of a thatch layer in established pastures could reduce the contact between broiler litter and soil, thus increasing the potential for surface runoff contamination with litter P. We conducted a laboratory study to evaluate the effect of a thatch layer on the dynamics of water-soluble P in undisturbed cores taken from a pasture. Cores with and without a thatch layer received a surface application of broiler litter (5 thm-2) and were incubated at 25 oC for 56 d. The result showed that on the soil surface the contents of water soluble-P (39 kghm-2) of the cores with the thatch layer was higher than that (20 kghm-2) of the cores without the thatch layer. Therefore on well-established pastures fertilized with broiler litter, the presence of a thatch layer might lead to high concentrations of water-soluble P on the soil surface. 展开更多
关键词 pastureS Water-soluble phosphorus Broiler litter
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Quantitative Simulation of Dynamic Changes in Cultivated Land in Areas of Reclamation and Returning Cultivated Land to Forest or Pastures under RCPs Climate Scenarios 被引量:1
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作者 刘唯清 齐元静 +1 位作者 姜群鸥 聂承静 《Agricultural Science & Technology》 CAS 2016年第1期178-187,共10页
Northeast China as one of important agricultural production bases is an area under reclamation and returning cultivated land to forests or pastures. Therefore, it is of great practical significance in guaranteeing the... Northeast China as one of important agricultural production bases is an area under reclamation and returning cultivated land to forests or pastures. Therefore, it is of great practical significance in guaranteeing the sustainable development and national food security to study the spatial and temporal variation of cultivated land in Northeast China under future climate scenarios. In this study, based on data of land use, natural environment and social-economy, dynamics of land system(DLS) model was used to to simulate the spatial distribution and changing trends of cultivated land in the typical areas of reclamation and returning cultivated land to forest or pastures in Northeast China during 2010-2030 under land use planning scenario and representative concentration pathways(RCPs) scenarios quantitatively.The results showed that the area of cultivated land had an overall decreasing trend under the land use planning scenario, but the area of upland field increased slightly from 2000 to 2010 and then declined greatly, while the area of paddy field continuously declined from 2000 to 2030. Under the Asia-Pacific Integrated model(AIM)scenario, the total area of cultivated land had a tendency to increase considerably,with the upland field expanding more obviously and the paddy field declining slightly.In addition, the cultivated land showed a greater decreasing trend under the model for energy supply strategy alternatives and their general environmental impact(MESSAGE) scenario compared to the land use planning scenario. Moreover, analysis on the conversion between different land use types indicated that the reclamation and returning cultivated land to forests or pastures was likely to continue under future scenarios, but the frequency of occurrence could decrease as the time goes by. The conclusions can provide significant decision-making information for the rational agricultural planning and cultivated land protection in Northeast China to adapt to the climate change. 展开更多
关键词 Land use Climate change Planning Cultivated land change Quantitative simulation Scenario Areas of reclamation and returning cultivated land to forest or pastures
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Predicting Levels of Crude Protein, Digestibility, Lignin and Cellulose in Temperate Pastures Using Hyperspectral Image Data 被引量:4
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作者 Susanne Thulin Michael J. Hill +2 位作者 Alex Held Simon Jones Peter Woodgate 《American Journal of Plant Sciences》 2014年第7期997-1019,共23页
Hyperspectral sensors provide the potential for direct estimation of pasture feed quality attributes. However, remote sensing retrieval of digestibility and fibre (lignin and cellulose) content of vegetation has prove... Hyperspectral sensors provide the potential for direct estimation of pasture feed quality attributes. However, remote sensing retrieval of digestibility and fibre (lignin and cellulose) content of vegetation has proven to be challenging since tissue optical properties may not be propagated to the canopy level in mixed cover types. In this study, partial least squares regression on spectra from HyMap and Hyperion imagery were used to construct predictive models for estimation of crude protein, digestibility, lignin and cellulose concentration in temperate pastures. HyMap and Hyperion imagery and field spectra were collected over four pasture sites in southern Victoria, Australia. Co-incident field samples were analyzed with wet chemistry methods for crude protein, lignin and cellulose concentration, and digestibility was calculated from fiber determinations. Spectral data were subset based on sites and time of year of collection. Reflectance spectra were extracted from the hyperspectral imagery and collated for analysis. Six different transformations including derivatives and continuum removal were applied to the spectra to enhance absorption features sensitive to the quality attributes. The transformed reflectance spectra were then subjected to partial least squares regression, with full cross-validation “leave-one-out” technique, against the quality attributes to assess effects of the spectral transformations and post-atmospheric smoothing techniques to construct predictive models. Model performance between spectrometers, subsets and attributes were assessed using a coefficient of variation (CV), —the interquantile (IQ) range of the attribute values divided by the root mean square error of prediction (RMSEP) from the models. The predictive models with the highest CVs were obtained for digestibility for all spectra types, with HyMap the highest. However, models with slightly lower CVs were obtained for crude protein, lignin and cellulose. The spectral regions for diagnostic wavelengths fell within the chlorophyll well, red edge, and 2000-2300 nm ligno-cellulose-protein regions, with some wavelengths selected between the 1600 and 1800 nm region sensitive to nitrogen, protein, lignin and cellulose. The digestibility models with the highest CV’s had confidence intervals corresponding to ±5% digestibility, which constitutes approximately 30% of the measured range. The cellulose and lignin models with the highest CV’s also had similar confidence intervals but the slopes of the prediction lines were substantially less than 1:1 indicating reduced sensitivity. The predictive relationships established here could be applied to categorizing pasture quality into range classes and to determine whether pastures are above or below for example threshold values for livestock productivity benchmarks. 展开更多
关键词 pasture Quality CRUDE Protein DIGESTIBILITY LIGNIN Cellulose HYPERSPECTRAL Remote Sensing Partial-Least SQUARES Regression
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Effects of Different Grazing Intensities on Vegetation Characteristics of Cultivated Pastures in Southern China 被引量:2
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作者 WAN Li-qiang,LI Xiang-lin ,HE Feng,CHEN Wei-wei,WAN Jiang-chun,ZHAO Yun,WU Wei-da Institute of Animal Sciences,Chinese Academy of Agricultural Sciences,Beijing 100193,China 《Animal Husbandry and Feed Science》 CAS 2012年第2期72-75,96,共5页
[Objective]The paper was to study the effect of different grazing intensities on vegetation characteristics of artificial pasture by plot rota- tion grazing experiment. [Method]Grazing intensity was divided into 2 tre... [Objective]The paper was to study the effect of different grazing intensities on vegetation characteristics of artificial pasture by plot rota- tion grazing experiment. [Method]Grazing intensity was divided into 2 treatments of heavy grazing and light grazing,and each treatment contained 6 plots,with randomized complete block design. A blank control was set near test plot. Ninety disease-free and healthy 2-year-old Yunling Black Goats with consistent body condition were selected and divided into 2 groups: heavy grazing ( 55) and light grazing ( 35) . The goats were conduc- ted rotation grazing in 6 plots,and the average stocking rates were 12. 6 and 8 goat /hm 2 . The plant height,coverage,underground biomass and pasture plant nutrition of 2 treatments were measured,respectively. [Result]The cocksfoot height had significant difference with control under graz- ing conditions ( P 〈0. 05) ,while the heights of ryegrass and white clover in control plot had no significant difference with that in grazing plot ( P 〉 0. 05) . Grazing intensity had different effects on coverage of different plants; grazing utilization reduced the coverage of cocksfoot and ryegrass, which had little impact on coverage of white clover; viewed from the whole plant communities,the coverage in control plot was greater than that in grazing plot. The underground biomass in 0 -20 cm soil depth in grazing plot accounted for about 90%; with the increase of grazing intensity,un- derground biomass was decreased. The crude protein ( CP) and crude fat ( EE) content of forage decreased,while acid detergent fiber ( ADF) and neutral detergent fiber ( NDF) increased. [Conclusion]The research provided scientific basis for determination of suitable grazing system and sus- tainable utilization of pasture resources. 展开更多
关键词 Grazing intensity Artificial pasture Vegetation characteristics
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Study on the Influence of Climatic Change on Pasture Growth in Inner Mongolia Grassland 被引量:1
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作者 Li Xinghua Liu Xiurong +1 位作者 Cao Yanfang Sun Xiaolong 《Meteorological and Environmental Research》 CAS 2014年第5期43-47,52,共6页
Through analyzing statistically metrological observation data from 1971 to 2010 and pasture data from 1983 to 2012 at 6 animal husbandry meteorological testing stations of Inner Mongolia grassland, the conclusions wer... Through analyzing statistically metrological observation data from 1971 to 2010 and pasture data from 1983 to 2012 at 6 animal husbandry meteorological testing stations of Inner Mongolia grassland, the conclusions were drawn. Those were that annual average temperature rose in a straight line in Inner Mongolia grassland, and the increase rates of annual average temperature in meadow steppe and typical steppe were 0.40 and 0.34 ℃/10 a respectively. Annual rainfall had 10-year cyclical characteristics, and precipitation in the 1990s was the most but reduced significantly after 2000. Climate experienced the cold wet -cold dry -warm wet -warm dry periods. Warm and dry climate made the average heights of pasture in meadow steppe and typical steppe of Inner Mongolia cut down 2.4 and 9.3 cm in nearly 12 years than that in the 1990s; the average coverage of herbage decreased by 11% and 13%; the average hay yields reduced by 1 019.8 and 671.4 kg/hm^2. 展开更多
关键词 Climatic change pasture growth period pasture height Grass coverage Hay yield China
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Cool-season annual pastures with clovers to supplement wintering beef cows nursing calves 被引量:1
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作者 Stacey A Gunter Whitney A Whitworth +1 位作者 T Gregory Montgomery Paul A Beck 《Journal of Animal Science and Biotechnology》 SCIE CAS 2012年第4期221-226,共6页
In December of 3 years, 87 beef cows with nursing calves (.594 ± 9.8 kg; calving season, September to November) at side were stratified by body condition score, body weight, cow age, and calf gender and divided... In December of 3 years, 87 beef cows with nursing calves (.594 ± 9.8 kg; calving season, September to November) at side were stratified by body condition score, body weight, cow age, and calf gender and divided randomly into 6 groups assigned to 1 of 6 cool-season annual pastures (0.45 ha/cow) that had been interseeded into a dormant common bermudagrass (Cynodon dactylon [L.] Pers.)/bahiagrass (Paspalum notatum Flugge) sod. Pastures contained 1 of the following 3 seeding mixtures (2 pastures/mixture): 1) wheat (Triticum aestivurn L.) and ryegrass (Lofium multiflorum Lain., WRG), 2) wheat and ryegrass plus red clover (Trifolium pretense L, WRR), or 3) wheat and ryegrass plus white (Trifofium repens L.) and crimson clovers (Trifolium incarnatum L., WRW). All groups had ad libitum access to grass hay (12% crude protein; 58% total digestible nutrients). The second week in December, cow estrous cycles were synchronized and artificially inseminated. In late December, a bull was placed with each group for 60-d. Data were analyzed with an analysis of variance using a mixed model containing treatment as the fixed effect and year as the random effect. Body weight and condition scores did not differ (P ≥ 0.27) among cows between February and June. Calf birth weights or average daily gain did not differ (P≥ 0.17) among treatments; however, calves grazing pastures with clovers did tend (P= 0.06) to weigh more than calves grazing grass only. Weaning weight per cow exposed to a bull was greater (P= 0.02) for WRR and WRW than WRG. Cows grazing winter-annual pastures containing clovers tended to wean more calf body weight per cow exposed to a bull than cows grazing the grass only pastures. 展开更多
关键词 Annual ryegrass Beef cows CLOVERS Nitrogen pasture 1
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Mountain Pastures and Grasslands in the SW Tien Shan,Kyrgyzstan-Floristic Patterns,Environmental Gradients,Phytogeography,and Grazing Impact 被引量:4
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作者 BORCHARDT Peter SCHICKHOFF Udo +1 位作者 SCHEITWEILER Sabrina KULIKOV Maksim 《Journal of Mountain Science》 SCIE CSCD 2011年第3期363-373,共11页
Vast grasslands are found in the walnut-fruit forest region of southern Kyrgyzstan,Middle Asia.Located above the worldwide unique walnutfruit forests and used for grazing,they play a pivotal role in the mixed mountain... Vast grasslands are found in the walnut-fruit forest region of southern Kyrgyzstan,Middle Asia.Located above the worldwide unique walnutfruit forests and used for grazing,they play a pivotal role in the mixed mountain agriculture of local farmers.Accordingly,these pastures are subject to an increasing utilization pressure reflecting the changing political and social conditions in the transformation process from a Soviet republic to an independent state.A first detailed analysis of mountain pasture vegetation in the Ferghana Range answers the following questions:What are the main plant community types among Kyrgyzstan's mountain pastures? What are the main environmental gradients that shape their species composition? Which phytogeographical distribution types are predominant? How does grazing affect community composition and species richness in these grasslands? Species composition was classified by cluster analysis;underlying environmental gradients were explored using DCA.A dataset of 395 relevés was used for classification,and a subset of 79 relevés was used in a DCA to analyze the correlation between vegetation,environment,and grazing impact.The investigated pastures were classified into four distinctive plant communities.The site factors altitude,heat load,inclination and grazing impact were found to be the major determinants of the vegetation pattern.A significant overlap between floristic composition and structural and spatial properties was shown.The majority of the species pool consisted of Middle Asian endemics and Eurosiberian species.However,disturbance-tolerant species played a significant role with respect to species composition and coverage of the herbaceous layer in vast areas of southern Kyrgyzstan's mountain pastures.In general,an intense grazing impact is clearly reflected by both species composition and structural variables of plant communities.The highly diverse and unique ecosystem is modified by an increasing utilization pressure.In order to maintain vital processes and functioning of this valuable ecosystem-in both economical and ecological terms-,it is indispensable to adopt appropriate pasture management strategies. 展开更多
关键词 Central Asia Classification ENDEMICS Gradient Analysis Grazing impact Middle Asia pasture Management Ruderals Transformation Process Walnut-fruit forest.
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Relation between some variations of soil and surface vegetation and desertization in agriculture-pasture interlacing zone——An example from Kangbao County, North Hebei, China
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作者 SHENGXue-bing LIUYun-xia 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第1期112-115,共4页
The studied agriculture\|pasture interlacing zone has its specific natural conditions, at which the natural systems are unstable, their self\|regulation capability is low and the equilibrium is easily broken, and henc... The studied agriculture\|pasture interlacing zone has its specific natural conditions, at which the natural systems are unstable, their self\|regulation capability is low and the equilibrium is easily broken, and hence the habitat is fairly vulnerable. During last 20 years the increasing population and livestock, over\|reclamation, over\|pasturing, over\|deforesting, and other intensified negative human activities in the zone resulted in coarsening of surface soil, decrease of organic mater content in soil, reduction of vegetation coverage, variation and degradation of flora structure, and hence in desertization of the land, although average of gales and sandstorms some decreased and the climate tended to be better in the region. However, the frequent sandstorms occurring in the springs of last and present years has attracted much attention. Investigations confirmed that the main cause for the phenomena is the unreasonable human activities rather than the natural factors. 展开更多
关键词 agriculture\|pasture interlacing zone SOIL SANDSTORM desertization
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Status of Mountain Pastures, Including Geobotanical Description of the Main Vegetation Associations in Western Pamir-Alay
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作者 Mukaddas B. Tirkasheva 《American Journal of Plant Sciences》 2019年第10期1689-1698,共10页
The article gives a brief description of the vegetation cover of the Western Pamir-Alai range, as well as a method of describing the phytocenosis of the vegetation of the studied region.
关键词 WESTERN Pamir-Alai pastureS PHYTOCENOSIS Formation Association FLORA
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Breaking Key Obstacles on Developing Circular Agriculture and Promoting Agricultural and Pasture Resources Benefit 被引量:1
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作者 Fengcui FAN Yu TIAN +2 位作者 Zhihong LI Jianming JIA Yufang SHI 《Asian Agricultural Research》 2013年第3期39-41,共3页
The present situation,problems and constraints of the circular agriculture development in Hebei Province are systematically analyzed,the subject modes suitable for the development of circular agriculture and the value... The present situation,problems and constraints of the circular agriculture development in Hebei Province are systematically analyzed,the subject modes suitable for the development of circular agriculture and the value-added potential are described,and finally some proposals are put forward. 展开更多
关键词 CIRCULAR AGRICULTURE MAJOR obstacles AGRICULTURAL
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Metabolic Adaptations Due to the Inclusion of Pasture in the Diet of Dairy Cows Fed Total Mixed Ration during Early Lactation
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作者 Ana Laura Astessiano Ana Meikle +3 位作者 Pablo Chilibroste Diego Antonio Mattiauda M. Fajardo Mariana Carriquiry 《Open Journal of Animal Sciences》 2017年第2期127-140,共14页
The aim of this study was to evaluate the metabolic adaptations due to the inclusion of pasture in the diet of dairy cows fed on a total mixed ration (TMR) ad libitum during early lactation. Multiparous cows (n=18) we... The aim of this study was to evaluate the metabolic adaptations due to the inclusion of pasture in the diet of dairy cows fed on a total mixed ration (TMR) ad libitum during early lactation. Multiparous cows (n=18) were used in a randomized complete block design and were randomly assigned according to parity, BW and BCS to one of two feeding strategies from calving to 60 DIM: 1) cows fed TMR ad libitum (without access to pasture;100% TMR) and 2) cows fed on a mixed system with pasture grazing (6 h of access to paddock in one grazing session, 8:00 to 14:00 h) and supplemented with 50% of ad libitum TMR (Pasture Group, PG). At 61DIM, TMR fed cows were assigned without an adjustment period to a similar feeding and management routine than PG group (Post-TMR), while PG cows remained in their original routine throughout the experiment. Thus, at 61DIM and thereafter, both, PG and Post-TMR cows grazed a second-year pasture and were supplemented with 50% TMR (DM basis). Milk production was determined daily until 80 DIM, and cow BCS and BW were registered and blood samples and liver biopsies were obtained one week before and one week after dietary change (-1 to +1 wk;+55 and +69 DIM). Milk yield, BW and BCS did not differ between treatments but decreased or tended to decreased from -1 to +1 wk only in Post-TMR cows. Serum IGF-1 tended to increase in Post-TMR cows. Hepatic expression of IGFBP5 and IGFBP6 mRNA, were greater while IGF1 and IGFBP3 mRNA tended to be greater for Post-TMR than PG cows. Hepatic expression of IGF1, IGFBP5 and IGFBP6 mRNA increased from -1 to +1 wk only in Post-TMR cows. Expression of ACADVL and PDH1A mRNA had a 2-fold increase in both groups from wks -1 to +1. The results confirm that changes in feeding strategy without an adaptation period modified animal metabolism. The inclusion of grazing to cows that were fed TMR during early lactation, increased IGF-1 concentrations and modified hepatic expression of genes related with IGF system and fatty acid metabolism indicating redistribution of nutrients and energy towards maintenance requirements (increased due to walking and grazing activity) in detriment of milk production. 展开更多
关键词 TURNOUT to pasture Hepatic Expression DAIRY CATTLE
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A Little Thought for Pasture Informatization Construction
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作者 Yan Lei Sun Yanqin +2 位作者 Yan Yuefei Zhu Yexia Zhang Zhen 《Animal Husbandry and Feed Science》 CAS 2017年第3期131-134,137,共5页
Dairy industry is an indispensable component of modem agriculture. How to improve informatization level and technology content of dairy industry and progress informationalization construction process of pastures has b... Dairy industry is an indispensable component of modem agriculture. How to improve informatization level and technology content of dairy industry and progress informationalization construction process of pastures has been one of the most popular topics in development of dairy industry in China. Compared with the countries with developed dairy industry worldwide, dairy industry in China is featured by not high informationization level and backward modernization level at the present stage. However, development and maturity of related technologies for pasture informatization construction provides a significant opportunity for transformation and upgrading and leaping development of dairy industry in China. 展开更多
关键词 Dairy breeding pasture Informatization construction Development status Problems THINKING
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