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1.
Photosynthetically active radiation use efficiency (PARUE) of orchardgrass (Dactylis glomerata L.) and tall fescue (Schedonorus phoenix (Scop.) Holub) was determined. Leaf mass was harvested for canopies at different shade levels when each reached 20 cm height with 5 cm residue for regrowth to simulate grazing. Total incident PAR at each site was summed for the growth period (S-PAR). Values for PARUE were calculated from dried leaf mass divided by S-PAR. The more highly shaded plants reached 20 cm at lower S-PAR. While overall leaf mass decreased linearly with shade induced decreases in S-PAR, PARUE increased exponentially. The coefficients for the equations representing this exponential increase vary for forage species and may represent a useful index for characterizing forage response to silvopastoral systems.  相似文献   

2.
Tagasaste (Chamaecytisus palmensis), a multipurpose fodder tree, is highly productive in the tropical highlands. The forage has high crude protein (CP) concentrations but is reported to have low intake by ruminants. This study investigated the effects of plant harvest stage and feeding management (wilted, dried and fresh) on levels of tannins in tagasaste and on preference and intake by Menz sheep and cattle fed during the dry season. The treatments were (1) fresh tagasaste, (2) wilted tagasaste, (3) dried tagasaste and (4) native hay. There were three preference experiments using sheep (20.2 ± 0.66 kg) to investigate intake under ad libitum or restricted offering of the forages, and to assess effect of harvest age (6- or 10-month regrowth age) on ad libitum intake. In two further experiments ad libitum offerings of the forages were evaluated using young steers (131.2 ± 19.6 kg) and heifers (156.3 ± 5.4 kg). The CP (201 g/kg), hydrolysable tannin (150.2 g/kg) and condensed tannin (8.97abs measured as absorbance at 550 nm wavelength/g NDF) contents of tagasaste forage were not affected by the physical treatments and harvesting stage. When fed ad libitum, sheep preferred (P < 0.01) fresh forage to wilted or dry tagasaste (24.5 vs. 22.9 and 7.9 g dry matter (DM)/kg metabolic body weight (MBW). The restricted offering increased intake of the less preferred dried form. Regrowth age (6 vs. 10 months) did not affect sheep preference. Unlike sheep, steers and heifers preferred (P < 0.01) dried tagasaste rather than the fresh or wilted forage. Animal preference and intake were affected by the preparation method of the forage, but not by regrowth age. Methods to improve intake (for cattle), effects of long-term feeding and evaluation on the subsequent effect of anti-nutritional compounds during digestion and animal performance should be further investigated.  相似文献   

3.
文中论述了木本饲料的概念及特点, 综述了木本饲料的饲用价值和饲用效果, 在对国内外木本饲料发展进行回顾和对我国发展木本饲料的必要性及有利条件进行分析的基础上, 针对我国木本饲用植物资源的状况, 提出了发展木本饲料的建议。  相似文献   

4.
在调查鉴定内蒙古贺兰山国家级自然保护区内的植物标本的基础上,结合查阅有关研究饲用植物资源文献,统计分析了保护区的野生饲用植物资源,结果表明,保护区内分布的野生饲用植物共有370种(含种以下单位),隶属57科188属。其中草本植物占绝对优势,共计302种,占保护区内饲用植物总种数的81.62%;从水分生态型分析,中生植物最多,有199种,占保护区内饲用植物总种数的53.79%。从饲用价值上看优等37种、良等101种、中等121种、低等91种、劣等20种,分别占保护区内饲用植物总种数的10%、27.30%、32.70%、24.59%和5.41%。良等以上饲用植物占该保护区野生饲用植物总种数的37.30%,可以看出该保护区饲用植物价值高,具有很高的开发利用潜力。本文还对该保护区野生饲用植物资源的保护及开发利用提出建议。  相似文献   

5.
Forage and wood yield of Acacia cyanophylla, also known as Acacia saligna, was studied in a 300–400 mm precipitation zone in Tunisia. Yields were measured during and after drought. This short (2–8 m) evergreen leguminous tree is used as a forage drought reserve in frost free regions where mean annual precipitation exceeds 250 mm. The standing crop of leafy forage builds up year after year for at least four years or until the tree is cut. It rapidly regrows after cutting from coppice shoots. The leaves provide high protein forage for sheep and goats during the long dry summer season typical of the Mediterranean climate as well as emergency forage during drought. The tree is used to stabilize moving sand dunes, and as a windbreak to protect cropland. It also provides fuelwood and increasaes soil nitrogen by fixation. The need for supplemental irrigation during establishment is a major constraint. Research in the 350 mm precipitation zone of Tunisia found 3.2 year old trees to yield over 1400 kg of forage standing crop per hectare after a severe drought. Trees harvested at 2.5 years of age in May, during the worst drought in over 30 years, yielded a standing forage crop of 724 kg per hectare. Forage regrowth 8 months after cutting and 4 months after rains returned was 700 kg/ha. The forage standing crop for trees harvested only once during the 3.2 year period was double the amount of forage regrowth from trees harvested the previous year, but mean annual forage yield similar. This demonstrates that it is possible for forage to be conserved as a living forage reserve for later use during drought. Total wood yield was only 1621 kg/ha for trees cut twice compared to 3683 kg/ha for trees cut only once. Annual cutting will substantially reduce the amount of forage available during drought and reduce the production of fuelwood. It may also reduce the vigor, productivity and life of the tree. Acacia cyanophylla alley cropped on cereal farmland can protect the soil from erosion, protect the associated crop from wind damage, fix nitrogen, provide fuelwood and provide a reserve of high quality forage for use during drought. This work was supported by the Government of Tunisia and the U.S.A.I.D. Tunisia Range Development and Management Project (664-0312.8).  相似文献   

6.
The nutritive value of edible forage from Leucaena leucocephala cv. Cunningham (CUNN) and cv. CNIA-250 (CNIA) was determined during the rainy (R) and dry (D) seasons of Cuba without fertilization or irrigation. Forage was supplied ad libitum and the French system of total faeces collection was used for nutritive value determination and expression by using six adult castrated Pelibuey wethers for each determination. There were noticeable differences in the chemical composition and nutritive value between the two cultivars which were also influenced by year season. The highest protein and energy content were found in CNIA and during the rainy season which could also explain its higher forage intake and digestibility, while CUNN expressed higher DM and nutrient yield throughout the year, mainly due to advantages in tree size and morphology (higher ramification and proportion of leaves, and acceptable branch length). Quality and nutritive value results indicated that these Leucaena cultivars have a suitable potential as supplements for sustainable ruminant nutrition strategies during both seasons of the year; CNIA, because of its smaller height, is strongly recommended for agrosilvopastoral small ruminant browsing systems.  相似文献   

7.
Interactions among ecosystem services are increasingly perceived as important to ecosystem service delivery. Synergies and trade-offs among ecosystem services arise through direct ecological interactions or indirectly through correlated responses to other factors. To investigate whether and how interactions of overstory trees and shrubs with livestock forage species growing beneath generate ecosystem service interactions, overstory and forage species were examined in smallholder fallows in western Kenya. In 18 grazed and 21 improved fallows, we estimated biomass and quantified soil properties. We assessed whether the overstory reduces forage biomass and quality through competition, and whether overstory niche complementarity ameliorates competition or enhances facilitation. In improved fallows, forage biomass declined with overstory biomass, indicating competition and a wood-forage trade-off. In grazed fallows, biomass of higher quality forage species increased with overstory biomass, indicating a synergy, likely indirect. Niche complementarity, quantified as taxonomic and functional diversity, did not appear influential. Forage quality was not associated with overstory characteristics, but declined with grazing intensity. The contrasting relationships between overstory and forage species among fallow types appear ultimately attributable to the presence and intensity of grazing and the dense overstory in improved fallows.  相似文献   

8.
Forage seeding, seeding grasses and legumes in conifer plantations, has been touted as a method of simultaneously improving elk (Cervus elaphus) and black-tailed deer (Odocoileus hemionus columbianus) nutrition and forest regeneration. When suited to local physiographical and biological conditions forage seeding may (1) increase the nutritional quality and biomass of forage preferred by cervids and (2) reduce the establishment of seral vegetation that competes with conifer seedlings. The effectiveness of forage seeding in reducing conifer browsing by cervids remains questionable. In the past, forage seeding programs have been implemented over wide geographic areas far beyond experimental study sites; many of these have had limited success. In addition, the effects of forage seeding on cervid biology and reforestation have not been rigorously tested. Thus, if forage seeding programs are implemented, it should be done so cautiously with the expectation that the outcome may differ markedly from prior experimental results. We outline criteria for selecting sites for forage seeding programs and prescribe methods for optimizing the seeding of forages. We offer guidelines for designing large-scale forage seeding research to infer treatment differences to a representative population of clearcuts with a specific set of clearly defined site conditions and management objectives. For situations where such large-scale experimentation is prohibitive, we outline research questions we believe are both important and can be answered in small-plot studies.  相似文献   

9.
为寻求适合毛乌素沙区大力发展舍饲养殖业的优质高产主效牧草品种,探索农牧交错牧业 可持续发展的有效途径,特在红石峡沙地引进7种牧草进行试验。结果表明,所引牧草新品种完全适生于引种区的气候条件和土壤条件,其抗逆性强,并能获得较高的经济、生态和社会效益。建议在毛乌素沙区大力推广。  相似文献   

10.
根据沙地饲料桑的生态学特性和生长特性,针对酒泉市开展沙地饲料桑育苗存在的许多问题,采用不同处理措施,进行了沙地饲料桑硬枝扦插育苗试验。结果表明,ABT生根粉、NAA和IBA等3种植物生长调节剂中,质量分数为100×10-6的ABT处理最适合沙地饲料桑的扦插繁殖,成活率为85.5%;质量分数为300×10-6的NAA处理效果次之,成活率成为83.4%;质量分数为300×10-6的ABT处理效果最差,成活率为67.2%。  相似文献   

11.
Silvopastures may have the potential to increase forage yields beneath trees compared to open pasture at some sites. This has been attributed to a combination of factors including improved water use efficiency by shaded grass and increased water availability through hydraulic lift by trees. The objectives of this research were to determine if silvopastures changed forage mass production and available soil water, and to determine how these two factors were related. Forage mass and soil water were sampled at 1.0, 2.0, and 3.6 m from the tree stem, or plot center under honey locust (Gleditsia triacanthos L.), black walnut (Juglans nigra L.) and shade cloth in 2006 and 2007. Soil water was measured in the top 10 cm of soil using a capacitance probe, and at 30-cm intervals, from 45 to 105 cm, using a neutron probe. Forage was collected to determine dry mass and annual yield. In 2006, forage mass was greater under black walnuts and honey locusts than under 70% shade cloth. In 2007, with a 50% shade cloth, forage growth was similar in all treatments. In both 2006 and 2007, soil moisture in the top 10 cm was higher under shade cloth compared to honey locust or black walnut trees. Similarities in forage mass between treatments in 2007 indicate that the differences in soil water were not biologically significant for forage growth. Lower forage mass under the 70% shade cloth in 2006 was due to suppressed growth from intense shading. The major implication for pasture managers is that trees in these pastures had no negative effect on soil water availability and forage growth.  相似文献   

12.
Agroforestry Systems - Sound management of native forests used for cattle grazing requires understanding the dynamics of forage productivity in the openings. Despite their importance, forage...  相似文献   

13.
以利用发挥沙棘的饲用价值为根本,兼顾考虑其生态效益的发挥,按照综合、可测、科学合理的指标确定原则,采用分级复合方法建立了饲用型沙棘品种选择评价指标体系,确定了生态效益指数、饲用适宜性指数、营养价值指数的计算方法;并结合饲用型沙棘品种引种试验的观测数据,筛选出饲用性能好的沙棘品种.  相似文献   

14.
Four forage management treatments, bahiagrass, common bermudagrass, Coastal bermudagrass, and timber only were established in 26-year-old loblolly pine plantation. Pine growth data were collected in 1984, 1990, and 1995, and forage production was evaluated at 21-day intervals from April to October from 1991 through 1995. Forage management practices improved timber production, increasing five-year merchantable volume growth by 13 m3 ha-1. Mean five-year forage crop yields differed among treatments (P = 0.05) with daily dry matter yields averaging 39, 46, and 48 kg ha-1 for bahiagrass, common bermudagrass, and Coastal bermudagrass, respectively. Forage nutritional quality did not differ among forage crops. Forage management treatment future net values were computed for a 5% real interest rate. Although the future net value for bahiagrass and common bermudagrass exceeded Coastal bermudagrass, the mean forage crop future net value was similar to the timber only treatment. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

15.
We undertook ethnobotanical study of forage/fodder plant species used by the Afar and Oromo (Kereyu and lttu) Nations in and around the semi=arid Awash National Park (ANP), Ethiopia. The study aimed at investigating and documenting indigenous knowledge (IK) on forage/fodder plant species and threats to their survival. Ninety-six in= formants between 20 and 80 years old were selected using prior informa- tion. Data were collected using semi-structured interview, guided field wail discussion and field observation. Preference ranking, Jaccard's coefficient of similarity and priority ranking were used for data analysis. One hundred twenty-six forage/fodder species of 90 genera and 43 fami- lies were collected in the study area. More than 88% of the species were reported with their vernacular names, where 68% were reported by the Afar Nation and 70% by the Oromo Nation. Family Poaceae was repre- sented by 25 species (20%), followed by Fabaceae 18 (14%). Preference ranking for the most preferred forage grasses as perceived by key informants revealed that Chrysopogon plumulosus was the most important forage/fodder species. Overgrazing was the major threat in the study area, scoring 22%.  相似文献   

16.
Resource sharing among agroforestry system components, as expressed by spatial patterns along interfaces between components, is a crucial factor in both understanding present systems and in designing new agroforestry applications. A study of the spatial pattern of forage production surrounding 9–10 year old Douglas-fir trees in a agrosilvopastoral plantation near Corvallis, Oregon, was conducted during 1988 and 1989. Transects of plots were clipped both between trees (tree/tree) and between trees and open pastures (tree/pasture). Best-fit regression models relating forage production to distance from trees (tree/tree R 2 = 0.87; and tree/pasture R 2 = 0.89) were combined into a single prediction model. Observed forage production increased rapidly with increasing distance from trees during the initial 4 m. Trees had little effect on forage production beyond 4.5 m (approximately 2 canopy diameters) from the nearest tree. Predictions of different combinations of tree density and planting pattern indicated a strong interaction between density and pattern with highly aggregated plantations better able to maintain forage production at high tree densities.  相似文献   

17.
采用光合衰减法,计算陕北6县1970~2000年各年度牧草的生产潜力,对影响该区域牧草生产力的主要因素加以分析。结果表明,气候条件中的降水因子直接影响着牧草的生产力,加之人文因素的干扰作用,导致牧草生产力水平下降。并通过对该区域自然、经济和社会条件的综合分析,探讨草场资源合理利用的有效途径。  相似文献   

18.
Forest management strongly influences the interactions between ungulates and their food resources. Different ungulate-adapted measures have been proposed in forestry to improve forage availability or to reduce browsing damage. However, the potential and feasibility of such measures are inadequately known. We studied the effects of harvest timing and slash treatment in final felling and commercial thinning on the availability of Scots pine Pinus sylvestris forage and its use by ungulates during winter in the Swedish boreal forests. Pellet group counts showed that moose (Alces alces) was the dominating species using the post-harvest stands. Under conventional slash treatment, final felling stands held on average 226 kg pine forage ha?1 after harvesting and commercial thinning stands 137 kg ha?1. Ungulate-adapted slash treatment increased the available forage biomass by 20 %, but had no significant effect on consumption of forage by ungulates. Time since harvest had the strongest effect on forage consumption; for example, under conventional slash treatment, there was a tenfold increase in consumption (3 vs. 33 kg ha?1) following final felling as exposure time increased from 2–3 to 4–5 months. Consumption was higher in thinned stands than in final felling stands for the first 3 months but not later. To increase ungulate use of the forage made available at harvest, pine-dominated stands should be harvested in the late autumn or early in the winter.  相似文献   

19.
以草业为纽带的桔园生态系统及其生态效益研究   总被引:5,自引:0,他引:5  
在浙西红壤桔园套种牧草,建立以草业为纽带的"桔-草-畜(渔)"复合生态系统,对调节园地小气候、减少水土流失、改良红壤、促进畜渔业发展,具有良好的作用,生态、经济、社会效益明显。  相似文献   

20.
沙生饲用灌木树种的适应性评价   总被引:1,自引:0,他引:1       下载免费PDF全文
试验对5个沙生灌木树种的引种、生物量、抗旱性、饲料成分及营养价值作了测试和分析,并与乌兰布和沙漠传统饲用灌木、牧草、农副产品饲料进行了比较。结果表明:花棒、梭梭和乔木状沙拐枣不同产地间在高生长、地径生长两个性状上差异显著;乔木状沙拐枣和杨柴的地上生物量低于多枝怪柳(对照)10.69%和18.87%,花棒、梭梭、毛条分别高于对照16.98%、27.04%和2.64%。所选5个树种7项生态生理综合指标反映的抗旱性均高于对照树种二白杨和小叶杨;适于在乌兰布和干旱环境中生长;粗脂肪、租纤维和无氮浸出物高于传统饲料汤、柳、榆树叶;饲料成分及营养价值高于玉米秸和小麦秸;11种氨基酸总含量分别为:毛条12.53%,花棒10.91%,传统饲料多枝栓柳为7.8%,紫花苜蓿1.18%,沙打旺1.24%,玉米秸0.82%,小麦秸1.05%.栽培沙生饲用灌木是沙区发展畜牧业的一条有利途径。  相似文献   

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