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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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Detection of Chrysops divaricatus(Diptera:Tabanidae)in Flat Pastures of the Central Yakutia Russian Federation
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作者 Alexander Dmitrievich Reshetnikov Anastasia Ivanovna Barashkova 《Journal of Food Science and Engineering》 2019年第2期63-67,共5页
In Central Yakutia of the Russian Federation 21 species and subspecies of horseflies of two genera are revealed:Chrysops(6 species)and Hybomitra(15 species and 1 subspecies).There are two marked species(dark forms):H.... In Central Yakutia of the Russian Federation 21 species and subspecies of horseflies of two genera are revealed:Chrysops(6 species)and Hybomitra(15 species and 1 subspecies).There are two marked species(dark forms):H.bimaculata var.bisignata and H.montana var.flaviceps.The most numerous species being the main center of population on pastures are 6:Hybomitra montana montana,H.lundbecki lundbecki,H.ciureai,H.arpadi,H.nitidifrons nitidifrons,H.nigricornis(in the amount of 81.46%fees).On the plain pastures Chrysops divaricatus is specified for the first time. 展开更多
关键词 Chrysops divaricatus horseflies pastures of horses
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Comparison of Acidity Parameters for Soils under Perennial and Annual Pastures in Victoria
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作者 LuoShengguo REWhite 《Journal of Northeast Agricultural University(English Edition)》 CAS 1997年第2期81-88,共8页
There are about 5 million ha of strongly acid soils (pH < 4.8 in 0.01 mol·L -1 CaCl 2 ) in Victoria and about 11 million ha of mildly acid soils (pH 4.8~5.5) that are considered susceptible to furthe... There are about 5 million ha of strongly acid soils (pH < 4.8 in 0.01 mol·L -1 CaCl 2 ) in Victoria and about 11 million ha of mildly acid soils (pH 4.8~5.5) that are considered susceptible to further acidification under current agricultural use. However, there appear to be differences in the rate of acidification, as measured by soil pH change, between soils under perennial pastures in the higher rainfall areas of southern Victoria and soils under annual pastures in the sheep-wheat areas of the north-east. Measurements made on representative soils from both regions showed that the southern soils generally had a higher pH buffer capacity, which was primarily determined by the organic carbon content. There was a consistent relationship between the short-term buffer capacity (measured by titration) and the long-term buffer capacity (measured by incubation), irrespective of the origin of the soils. Exchangeable Al, measured in 0.01 mol·L -1 CaCl 2 , was strongly negatively correlated with pH and the relationship for all soils suggested that Al was adsorbed as a cation with an average charge of 1.2 展开更多
关键词 ACIDITY buffering capacity exchangeable aluminium organic carbon content pastures soil pH
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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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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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An Emergy-Based Approach to Assess and Valuate Ecosystem Services of Tropical Wetland Pastures in Brazil
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作者 Sandra Aparecida Santos Fabio Takahashi +5 位作者 Evaldo Luis Cardoso Claudio Flores Luiz Orcirio Fialho de Oliveira Geraldo da Silva e Souza Eliane Goncalves Gomes Enrique Ortega 《Open Journal of Ecology》 2020年第5期303-319,共17页
Wetland grasslands are important ecosystems for raising beef cattle, because they are highly productive and present forages with high quality. Most of these ecosystems are threatened by overgrazing or by being replace... Wetland grasslands are important ecosystems for raising beef cattle, because they are highly productive and present forages with high quality. Most of these ecosystems are threatened by overgrazing or by being replaced by exotic pastures. Emergy synthesis approach was used to assess and value the services provided by native pastures wetland under three conservation status and also to compare them to exotic pastures on wetlands. The ecosystem service that was assessed included forage provision for calves production estimated from grazing capacity of cow with calf at the foot. Habitat maintenance to plant diversity and wild herbivores were also evaluated. The results showed that natural wetland pastures with better conservation status provided valuable ecosystem services and are highly renewable. Data envelopment analysis (DEA) showed that regardless of the conservation state of the natural pastures, wet native grasslands were more efficient than wet exotic grasslands. Replacing native pastures by exotic ones may reduce plant diversity and the renewability of the system. The proposed method has a holistic approach to pasture ecosystems and is able to help decision-makers to define sustainable management practices and to subsidise public policies when it comes to payments regarding ecosystem services. 展开更多
关键词 Data Envelopment Analysis Forage Resources Natural Pasture Plant Diversity SUSTAINABILITY
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Effects of Enclosure on Grassland Ecological and Economic Benefits in Northern China
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作者 HU Bo WEN Qingke +3 位作者 XI Fengjiang LI Mengyao WANG Libing REN Yuejuan 《Chinese Geographical Science》 SCIE CSCD 2024年第1期67-78,共12页
Grasslands in northern China serve the country as both an ecological barrier and a livestock production base.There,installing enclosures has been becoming the major grassland restoration measure adopted by many local ... Grasslands in northern China serve the country as both an ecological barrier and a livestock production base.There,installing enclosures has been becoming the major grassland restoration measure adopted by many local governments.However,the effects of restoration on both ecological and production benefits of grassland remain unclear for implemented grassland restoration policies.Therefore,a representative rangeland in northern China,the Maodeng pasture in Inner Mongolia Autonomous Region was selected as the study area,and remote sensing monitoring analyses were carried out to quantify the ecological benefits and economic benefits from 2015 to 2021.The results showed that:1) in terms of ecological benefits,the grassland area with a grassland coverage rate of more than 60% accounts for 32.3% of the regional area,and 86.4% of its grassland grew significantly better than the same period in2015,showing a significant improvement in grassland growth.Using the average amount of carbon per unit area as the ecological benefit evaluation index,it increased by 27.1% to 32.48Tg C/yr from 2015 to 2021.2) In terms of economic benefits,both theoretical grass production and livestock carrying capacity increased from 2015 to 2021.Compared to 2015,the theoretical grass production in 2021 increased by 24.8% to 71 900 t.The livestock carrying capacity reached 52 100 sheep units in 2021,nearly 11 000 sheep units more than that in 2015.During the study period,multiple economic indicators(on a per capita basis of permanent residents) for the pastoral area of Xilinhot City to which the Maodeng pasture belongs,have grown steadily.Per capita total income rose from 29 630 yuan(RMB) in2015 to 62 859 yuan(RMB) in 2021.Relying on grassland resources to develop the pastoral ecology also broadens the potential economic development space.Overall,the establishment of the reserve and the experiment of implanting an enclosure policy have had a significant and positive impact on Maodeng pasture’s development from both an ecological and economic perspective.With the support of scientific evidence,enclosure policy can be extended to more than 110 000 km~2 of grasslands in northern China with similar precipitation and temperature conditions,enhancing the productive and ecological potential of grasslands.The above research results will contribute to the scientific formulation of grassland pasture quality improvement plans in northern China. 展开更多
关键词 ENCLOSURE GRASSLAND ecological benefit economic benefit Maodeng pasture Inner Mongolia northern China
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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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TOWARD GREENER PASTURES
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《Beijing Review》 2017年第39期12-15,共4页
The 19th National Congress of the Communist Party of China(CPC)will be held in Beijing on October 18.Led by the strong leadership of the CPC Central Committee with Xi Jinping at the core,China has made extraordinary a... The 19th National Congress of the Communist Party of China(CPC)will be held in Beijing on October 18.Led by the strong leadership of the CPC Central Committee with Xi Jinping at the core,China has made extraordinary achievements both at home and on the world stage since the 18th CPC National Congress was held in November 2012. 展开更多
关键词 CPC TOWARD GREENER pastures
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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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Grazing impact on forage quality and macronutrient content of rangelands in Qilian Mountains, NW China 被引量:1
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作者 Alina BARANOVA Jens OLDELAND +1 位作者 WANG Shun-li Udo SCHICKHOFF 《Journal of Mountain Science》 SCIE CSCD 2019年第1期43-53,共11页
An important indicator of the rangeland health, associated with land degradation, is the ability of semi-natural rangelands to provide forage of sufficient quality for livestock production. In Qilian Mountains(Gansu P... An important indicator of the rangeland health, associated with land degradation, is the ability of semi-natural rangelands to provide forage of sufficient quality for livestock production. In Qilian Mountains(Gansu Province, NW China) biomass production and forage quality are dependent on the seasonality of precipitation and temperature; most of the precipitation falls during summer season, when sheep, goats and yaks graze mountain rangelands. To sustain the rangelands and to improve the management strategies, the assessment of the forage quality should be implemented. The purpose of this research was to study the response of biomass, forage quality and macronutrient content different levels of grazing intensity in Qilian rangelands. We sampled aboveground biomass in the growing seasons in 2012 and 2013 within spring/autumn or summer grazing regimes in two altitudinal zones below and above 3000 m a.s.l.(montane-subalpine and subalpine-alpine respectively). In order to estimate forage quality, biomass was sampled in 1 m × 1 m plots, assigned to the center of 10 ×10 m sites, fromwhich we collected different indicator parameters of rangeland health. Mineral and fiber content of forage biomass was estimated under different levels of grazing intensity with regard to the growing period. It was found that an increase in grazing intensity led to a decrease in dry matter weight. No linearity was observed in the relationship between nutritive value and grazing intensity. The highest fiber content(59.20 %) was found in plots mostly disturbed by grazing. The highest protein(16.30 %) and the lowest fiber(51.30 %) contents were associated with slightly grazing intensity. Concentrations of the mineral elements, such as Zn, P, K and S varied significantly and showed maximum values under low grazing intensity. 展开更多
关键词 Grazing intensity Nutritive value FORAGE quality Mineral concentrations Alpine Subalpine pastures
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Relative Competitiveness of Nimblewill (Muhlenbergia schreberi) with Tall Fescues and Kentucky Bluegrass 被引量:2
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作者 Pedro V. D. Moraes Willian W. Witt +2 位作者 Timothy D. Phillips Patricia Rossi Luis E. Panozzo 《American Journal of Plant Sciences》 2014年第26期3777-3787,共11页
Nimblewill (Muhlenbergia schreberi) is a warm-season perennial grass (weed) native to the United States and Canada with low palatability. This species is dominant in many horse pastures in which bluegrass (Poa pratens... Nimblewill (Muhlenbergia schreberi) is a warm-season perennial grass (weed) native to the United States and Canada with low palatability. This species is dominant in many horse pastures in which bluegrass (Poa pratensis) is the primary forage. Tall fescues infected with endophyte fungae gives tall fescue plants greater competitividade ability and enviromental stress tolerance than their noninfected counterparts. The purpose of this study was to compare the relative competitiveness of nimblewill with bluegrass and tall fescues (Lolium arundinaceum) with or without endophytic fungi (strain AR584) through experiments using a replacement series design. Replacement series experiments were conducted in pots to evaluate the growth of species in a pure stand and in a mix stand with variables rates. Species competitiveness was evaluated based on the relative yield and relative yield total (and competitiveness index) of the dry weight of shoots from species grown together. Nimblewill was found to be more competitive than bluegrass, and all tall fescues were more competitive than nimblewill. Our results demonstrated that the presence of endophytes in three different tall fescues did not alter the competitiveness of these fescues with nimblewill, but the tall fescue Kentucky 31 was more competitive between tall fescues. Based on our finding, we concluded that fescues are recommended, especially without the endophytic fungi to suppress nimblewill in implantation of pastures to horses. 展开更多
关键词 COMPETITION pastures WEED ENDOPHYTIC FUNGI
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Fodder Halophytes for Saline Lands of Kyzylkum Desert 被引量:1
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作者 Lola S. Ortiqova 《American Journal of Plant Sciences》 2019年第9期1517-1526,共10页
The article is devoted to the economic and biological characteristics of promising desert semi-shrub halophytes (Kochia prostrate, Salsola orientalis, Ceratoides ewersmaniana, Halothamhus subaphyllus, Camphorosma less... The article is devoted to the economic and biological characteristics of promising desert semi-shrub halophytes (Kochia prostrate, Salsola orientalis, Ceratoides ewersmaniana, Halothamhus subaphyllus, Camphorosma lessingii) to improve saline lands of the Kyzylkum desert. 展开更多
关键词 Kyzylkum DESERT pastures SALINE Lands Karakul
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Rumen Degradability and Post-ruminal Digestion of Nitrogen and Amino acids by Cows Grazing Temperate Pasture
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作者 AIBIBULA Yimamu HALIDAI Rehemujiang +1 位作者 MASAAKI Hanada MEIJI Okamoto 《Asian Agricultural Research》 2015年第5期72-78,共7页
This experiment was conducted to evaluate nutrient digestion in the rumen and flow to the duodenum of steers grazed on orchardgrass( Dactylis glomerata L.,OG) or meadowfescue( Festuca pratensis Huds.,MF.) pastures loc... This experiment was conducted to evaluate nutrient digestion in the rumen and flow to the duodenum of steers grazed on orchardgrass( Dactylis glomerata L.,OG) or meadowfescue( Festuca pratensis Huds.,MF.) pastures located on northern part of Japan without supplement. Fifty-two digestion trials were carried out grazing Holstein steers fitted with cannulas in the rumen,duodenum and distal ileum in the three years. The pastures were divided into several paddocks,and the steers grazed each paddock for a day and allowed double of dry requirements the grazing cattle. The pre-grazing herbage mass did not significantly differ between pastures but the crude protein( N × 6. 25) content of herbage ranged from 19. 3% to 27. 5% on OG pasture and from 20. 0% to 32. 8% on MF pasture. Total N and AA-N intake did not differ but the degradability of dietary nitrogen in the rumen( RDN) was higher in MF than in OG pasture. The ratio of RDN to OM truly digested in the rumen was negatively related to the apparent N absorption in the rumen,and it was suggested that the amount of apparent N absorption in the rumen would be positive when the ratio was above 25 g / kg. Non-ammonia nitrogen( NAN) and AA-N flows to the duodenum of steers were lower in MF than in OG pasture. Duodenal AA flows were more linked to duodenal NAN flows and accounted for approximately 60% of duodenal NAN flows. The proportion of methionine and lysine slightly increased in the duodenal flows compared with the consumed AA,but a comparison between the essential AA composition of milk and the lean tissue indicated that duodenal digesta was most limiting in methionine,lysine,arginine,and histidine,and that deficiencies of arginine and histidine for milk production were relatively small. 展开更多
关键词 GRAZING COWS TEMPERATE pastures NITROGEN Degradabi
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Tolerance of Urochloa brizantha cv.MG5 to Mn Toxicity
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作者 Valéria Santos Cavalcante Gustavo Caione +2 位作者 Luiz Felipe Gevenez de Souza Renato de Mello Prado Anderson Fernando Wamser 《Open Journal of Soil Science》 2013年第8期379-383,共5页
Available information of the effects of manganese nutrition on the forage genus Urochloa is scarce. In the context, this study aims to evaluate the tolerance of Urochloa brizantha cv. MG5 to Mn toxicity. The experimen... Available information of the effects of manganese nutrition on the forage genus Urochloa is scarce. In the context, this study aims to evaluate the tolerance of Urochloa brizantha cv. MG5 to Mn toxicity. The experiment was conducted in a greenhouse at the University of the State of Sao Paulo (UNESP) in the city of Jaboticabal, SP. Plants were cultivated in vases (3.5 L) filled with soil according to a completely randomized experimental design comprising of five levels of Mn (0, 15, 30, 60 and 120 mg?dm?3) and four replications and cut in two periods: one is 42 days after sowing and the other is 30 days after the first one. Samples from both cuts were evaluated as to plant height, number of leaves and tillers, dry weight, Mn content and accumulation, and the green index was determined in the last cut. Manganese addition to soil caused an increase in chlorophyll content at the dosage of 68 mg?dm?3 observed in the second plant cut. Dosages of Mn above 15 mg?dm?3 did not induce increases in nutrient accumulation and in the number of leaves in the first and second cuts of the grass, and tillers in the first cut. The highest concentrations of manganese in the shoots did not produce visual symptoms of damage or a decrease in forage productivity demonstrating that Urochloa brizantha cv. MG5 has high tolerance to manganese toxicity. 展开更多
关键词 FORAGE pastures Plant Nutrition Soil Fertility MICRONUTRIENT
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Modeling the relationship of land use change and some geophysical indicators for the interlock area of farming and pasturing in China 被引量:19
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作者 DENG Xiangzheng, LIU Jiyuan, ZHUANG Dafang, ZHAN Jinyan, ZHAO Tao(Inst. of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 2002年第4期397-404,共8页
This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP) in northern China. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorph... This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP) in northern China. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorphic units and geophysical conditions-constraints or advantages. Additionally, it selects some indicators, according to the availability in acquiring and processing their quantitative data, to analyze the canonical correlations between the typical conversion of grassland and geophysical conditions. The preliminary study indicates that the physical conditions are of great advantages to the development of grassland. There exists significant correlation between land use change and some geophysical conditions. 展开更多
关键词 land use driving force interlock area of farming and pasturing China
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Post-mining policies and practices in the Eastern USA coal region 被引量:8
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作者 Jeff Skousen Carl E.Zipper 《International Journal of Coal Science & Technology》 EI CAS 2014年第2期135-151,共17页
Surface coal mines prior to 1950 in the USA were generally left without any reclamation.As government regulations advanced since then,mine operators were required to backfill the area and plant grasses or trees.After ... Surface coal mines prior to 1950 in the USA were generally left without any reclamation.As government regulations advanced since then,mine operators were required to backfill the area and plant grasses or trees.After the federal Surface Mining Control and Reclamation Act(SMCRA)was passed in 1977 in the USA,mine operators were required to conduct pre-mining analyses of the site and to designate a land use that could be achieved after mining.Successful reclamation,as needed to satisfy today’s societal demands,requires engineering,design,and purposeful reconstruction of the full mining disturbance,not just its surface,and control of waters leaving the mine site.Effective reclamation on modern American coal mines is fully integrated with the mining operation.A suitable and effective postmining land use that is sustainable for future generations is crucial to the long-term success and profitability of the mining business and to the future economic benefits of the landowner.Accepted post-mining land uses in the USA are:(1)prime farmland,(2)hay land and pasture,(3)biofuel crops,(4)forestry,(5)wildlife habitat,and(6)building site development.Policies and regulations for each post-mining land use were developed and practices to achieve successful and sustainable land uses were established.Post-mining conditions should provide ecosystem services and produce lands capable of supporting societal needs in the future. 展开更多
关键词 BIOFUEL Commercial development Laws and regulations PASTURE Prime farmland REFORESTATION Water quality Wildlife habitat
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Impacts of grazing and mowing on reproductive behaviors of Stipa grandis and Stipa krylovii in a semi-arid area 被引量:2
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作者 Hui GAO YuBao GAO XingDong HE 《Journal of Arid Land》 SCIE CSCD 2014年第1期97-104,共8页
Disturbance can affect biomass allocation of plants,but can it influence plant reproductive behavior?To address this issue,we performed field plant community investigations and explored the reproductive behaviors of S... Disturbance can affect biomass allocation of plants,but can it influence plant reproductive behavior?To address this issue,we performed field plant community investigations and explored the reproductive behaviors of Stipa grandis and Stipa krylovii in response to grazing and mowing treatments at Maodeng pasture of Xilinguole League of Inner Mongolia,China during 2007–2009.The results showed that,with a similar niche width for the two plant species under mowing and grazing treatments,mowing significantly increased the ratio of ramet to genet number of S.krylovii and the carbon to nitrogen ratio of S.grandis,and grazing significantly decreased the ratio of vegetative to reproductive tiller biomass of S.grandis and increased the ratio of vegetative to reproductive tiller number of S.krylovii.Regression analysis showed that the significantly positive effect of root to shoot biomass ratio was stronger on the ratio of vegetative to reproductive tiller number of S.grandis than on that of S.krylovii.These results indicated that grazing and mowing influenced the reproductive manner and the process of sexual reproduction of S.grandis and S.krylovii. 展开更多
关键词 Stipa grandis Stipa krylovii DISTURBANCE Maodeng pasture reproductive strategy
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Spatial Differentiation Characteristics of Human Settlements and Their Responses to Natural and Socioeconomic Conditions in the Marginal Zone of an Uninhabited Area,Changtang Plateau,China 被引量:1
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作者 ZHANG Haipeng LIU Hanchu +1 位作者 SUN Yong HE Renwei 《Chinese Geographical Science》 SCIE CSCD 2022年第3期506-520,共15页
The Changtang Plateau(CTP)in Qinghai-Tibet Plateau of China is one of the top-10 uninhabited areas with the most important ecological value in the world.It is of great academic and practical significance to carry out ... The Changtang Plateau(CTP)in Qinghai-Tibet Plateau of China is one of the top-10 uninhabited areas with the most important ecological value in the world.It is of great academic and practical significance to carry out research on human settlements in the marginal zones of the uninhabited areas to promote harmonious coexistence between humans and nature on the CTP.Using high-definition remote-sensing images to visually interpret and identify settlement-patch data,combined with field investigations,this study explores the spatial characteristics of human settlements in Shuanghu and Nyima counties and their responses to natural and socioeconomic conditions in the hinterland of the CTP.Findings reveal that the scale of human settlements on the CTP is extremely small,and density is very sparse.Settlements on the CTP primarily consist of several households,with some containing more than a dozen households,or are sub-village scale.Socioeconomic development is low and socioeconomic factors have a weak influence on the settlement layout on the CTP.Natural factors are the core elements affecting the layout of human settlements on the CTP.Settlements tend to occur on low mountains,gentle slopes,and areas with high average annual temperatures.Careful settlement site selection can help to mitigate the impact of natural disasters.To meet the needs of grazing,settlement layouts must typically have a high-quality grassland orientation.Riverbanks are key settlement areas,and settlement sites are often far away from alpine salt lakes.The characteristics of settlements on the CTP and their responses to environmental conditions significantly differ from those of human settlements in low-altitude inland areas. 展开更多
关键词 alpine pasture SETTLEMENT spatial differentiation influencing factors Qinghai-Tibet Plateau Changtang Plateau China
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