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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
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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
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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
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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
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Preparation of silage is a common method to preserve green forage. It plays an important role in improving forage utilization, 相似文献
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《Journal of Sustainable Forestry》2013,32(2-3):29-44
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
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T. R. Clason 《Agroforestry Systems》1998,44(2-3):293-303
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
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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
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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
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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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Lars Edenius Jean-Michel Roberge Johan Månsson Göran Ericsson 《European Journal of Forest Research》2014,133(1):191-198
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
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4种禾本科牧草种子的抗旱性评价 总被引：10，自引：0，他引：10
通过对20%PEG处理种子96 h后的胚芽伸长速度、种子吸水速率、种子萌发胁迫指数等3项抗旱性指标的测定,并采用抗旱性综合评价法,评价了狗牙根(1号)、波特鸭茅(2号)、德梅特苇状羊茅(3号)、黑籽雀稗(4号)4种禾本科牧草种子的抗旱性能。用20%PEG处理种子96 h后的胚芽伸长速度评价4种牧草种子的抗旱性,其抗旱性由强至弱的顺序为:3号>2号=4号>1号;用种子吸水速率评价4种牧草种子的抗旱性,抗旱性由强至弱的顺序为:2号>4号>3号>1号;用种子萌发胁迫指数评价4种牧草种子的抗旱性,抗旱性由强至弱的顺序为:3号>1号>4号=2号;用综合评价方法评价4种牧草种子的抗旱性,抗旱性由强至弱的顺序为:3号>2号>4号>1号。 相似文献
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Rapid conversion of lodgepole pine (Pinus contorta) dominated landscapes in western Alberta to a mosaic of successional stand ages has long-term implications for elk populations in the region that have not been fully assessed. We developed stand-level models of forage succession using data from 159 cutblocks to simulate forage and cover availability within the home range of an elk under “even-flow” and “pulsed” timber cutting scenarios that are common in this area. We found forage biomass peaked approximately 9 years following felling for both herbaceous (graminoids and forbs) and palatable browse forage. Forage production was determined primarily by the age of the cutblock (time since felling) and to a lesser extent elevation, compound topographic index (a measure of site wetness), and the distance to the nearest deciduous forest patch. Forbs became increasingly abundant as stands matured. Browse composition shifted from palatable species to unpalatable species after approximately 30 years. Within an elk home range (100 km2), we found that simulating an “even-flow” cutting regime resulted in forage availability that was always higher than under the current conditions of 90% forests when more than 10 ha were harvested per year. Further, forest cover (>30-year-old stands) was never less than the guideline of 60% of the area needed to provide adequate thermal and hiding cover. In contrast, when a “pulsed” harvest scenario was simulated, similar to what occurs for mountain pine beetle control, forage availability changed dramatically over time as a large cohort of harvested timber aged. Without further harvesting the stand conditions in the home range eventually returned to a state of pre-harvest risk for mountain pine beetle outbreak. We demonstrated several additional harvesting scenarios that avoided the potential risk and produced a much higher level of forage than currently exists. 相似文献
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华西雨屏区不同密度柳杉林下两种牧草生长效果评价 总被引：2，自引：0，他引：2
针对川西低山丘陵区坡耕地发展林草复合模式的需要,选择"柳杉+多年生黑麦草"和"柳杉+苇状羊茅"两种林草复合模式,研究在不同密度柳杉林(2 222株.hm-2、1 667株.hm-2、1 333株.hm-2、1 111株.hm-2)下多年生黑麦草和苇状羊茅的净光合速率、草高及生物量的变化。结果表明:(1)随着柳杉林密度的降低,两种牧草的净光合速率、草高和生物量均表现为上升趋势,但净光合速率差异均不显著(P0.05),黑麦草草高和生物量在柳杉林各密度下差异显著(P0.05);(2)4种柳杉林密度下,两种牧草净光合速率均为苇状羊茅多年生黑麦草,但随着柳杉林密度的降低,两者之间差值减小;(3)4种柳杉林密度下,黑麦草草高和生物量均明显高于苇状羊茅,且随着柳杉密度的增加,差值越大。 相似文献
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S. H. Sharrow 《Agroforestry Systems》1991,16(2):167-175
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