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1.
A survey of the use of trees, shrubs and herbs for livestock production was conducted through questionnaires among 90 farmers in the communal areas of northern KwaZulu-Natal in South Africa. The areas surveyed were located at Mtubatuba, Hluhluwe, Kwadlangezwa and Jozini. All the farmers questioned were found to own some form of livestock, mostly the Nguni breed. The commonly perceived sources of constraints on livestock production were external and internal parasites. The well known plants reported to be consumed by the animals were Vitellariopsis arginata and Rhus gueinzii. Most of the farmers (27.7%) used Cissus quadrangularis and Gnidia kraussiana for treating worm infestations and coughs in livestock. Plants used for increasing milk production were Crinum macowanii and Sarcostemma viminale. The well known plant species detrimental to livestock was Moraea spathulata, which causes diarrhoea and death.  相似文献   

2.
Vernonia amygdalina and Annona senegalensis, two plants used by local/smallholder livestock farmers in Nigeria as anthelmintic were screened for in vitro anthelmintic activity using Haemonchus contortus eggs. The extract of V. amygdalina did not show any significant activity at concentrations up to 11.2mg/ml. The extract of A. senegalensis showed significant (P<0.001) reduction in egg hatch at a concentration of 7.1mg/ml. The in vitro fecal culture of eggs with A. senegalensis showed significant (P<0.001) reductions in larval recovery with increasing concentrations from 1 to 10% ((w/w) in fecal culture) when whole ground plant material was used. Although traditional veterinary healers and local livestock farmers claim both plants are effective as anthelmintics, our result indicate that only A. senegalensis showed promising anthelmintic activity especially with use of ground whole plant materials as used by some farmers.  相似文献   

3.
Livestock traders are a key conduit for incentives in livestock production systems. Their actions affect producer prices, investment decisions, and their livelihoods. However, smallholder farmers in rural communities of eastern Africa often have limited understanding of the marketing process and the interactions among market actors. This study was undertaken following the introduction of improved indigenous goat and sheep breeds in Climate Smart Villages of Nyando in western Kenya. We sought to understand the marketing of sheep and goats in five key rural markets used by the smallholder farmers of Nyando, to generate information on key market actors, their functions in the value chain, and their preferences for attributes in sheep and goats. Most traders (65%) in all the markets were men. Four different types of traders operated in the markets, producers, retailers, wholesalers, and brokers, each making a profit. Preference for selling sheep or goats and the animal attributes desired by the traders differed depending on the surrounding community. Markets in Kericho County of Nyando traded more goats than sheep while those in Kisumu County of Nyando traded more sheep than goats. There were no clear policies guiding pricing of animals. Prices offered to producers depended on previous days, and the number of animals available for sale at the marketing point. The collaborative group actions of the producers in the Climate Smart Villages did not extend beyond the level of production to the marketing of their livestock. A critical change is required for the smallholder farmers to derive better incomes from improved quality of animals following adoption of improved breeding and management practices. The results illustrate the need to engage rural market actors when implementing livestock improvement programs for smallholder farmers for better farm gate prices of animals, and thus achieve the improved incomes envisioned.  相似文献   

4.
Inselbergs are regarded as ‘islands of diversity’ due to the high number of plant species present and level of endemism. They also act as natural sources of fodder for livestock and thus risk becoming homogenised in a heavily grazed rangeland. The aim of this study was to compare plant diversity on inselbergs and matrices in heavily grazed sections of three arid biomes of South Africa’s west. The inselbergs are scattered in a matrix of rangeland vegetation in the Desert, Nama-Karoo and Succulent Karoo biomes where pastoral herding is the main land use. Plant composition, cover and growth forms were quantified in plots and along transects in 21 inselberg and matrix sites. Inselbergs had more diverse plant and growth forms and greater cover than adjacent matrices. Defoliated plants on inselbergs are able to recover due to more mesic conditions and because inselbergs are largely grazed during drier periods, species are able to flower and set seed during winter. Inselbergs are also less accessible to livestock due to their unique geomorphology. Therefore, inselbergs are able to persist as islands of diversity and warrant inclusion into conservation and rangeland farming management plans since climate change will result in biome boundary shifts.  相似文献   

5.
通过实地考察和植物标本的采集与鉴定,并结合相关文献资料的查阅,对新疆西昆仑山禾本科植物物种多样性特点进行了研究。结果表明,新疆西昆仑山的禾本科植物共计37属137种,分别占新疆禾本科植物属、种总数的52.11%和42.55%,属种丰富度比较高;其中发现该区新记录植物6种。本区禾本科植物特有现象不明显,属的组成以仅含1种的属(17属17种)和少种属(13属35种)为主,共计30属52种,分别占属、种总数的81.08%和37.96%;中型属(4属32种)和较大属(3属53种)共计7属85种,分别占属、种总数的18.92%和62.04%,在种级水平占据明显优势,是该区系的主体。区系地理成分有6个分布类型和4个变型,以温带分布及其变型为主。植物生活型以多年生草本(116种,占84.67%)为主,其次为一年生草本(21种,占15.33%)。生态型以中生植物(63种,占45.99%)和旱生植物(61种,占44.53%)为主,显示其与草原、草甸的密切关系,另有少量湿生植物(13种,占9.49%)。说明该地区比较适合禾本科多年生的旱生和中生植物生长,且该区系的禾本科植物地理成分类型与该区所处地理位置为温带较吻合。  相似文献   

6.
荒漠绿洲过渡带天然植被对于绿洲生态环境的维护具有非常重要的意义。土地利用等绿洲化的人类活动如何影响天然植被对于评估过渡带的植被结构和功能非常重要。生态化学计量学在限制性营养判断和评估生态系统稳定性上得到了广泛利用。以塔克拉玛干沙漠南缘典型植物多枝柽柳、疏叶骆驼刺和花花柴为研究对象,研究不同土地利用方式和强度对植物碳(C)、氮(N)、磷(P)、C∶N、C∶P和N∶P的影响。研究表明,3种植物的C、N、P、C∶N、C∶P和N∶P平均值分别为385.94 mg·g-1、13.62 mg·g-1、1.49 mg·g-1、30.33、294.01和9.69。与干旱区以及全球其他群落类型相比,植物C和P处于中间水平,而N则普遍低于其他区域。土壤的利用方式、强度以及二者的交互作用能够显著影响大部分指标。过渡带不同利用方式外围荒漠样点C、N、P及其比值差异较大,土地利用后也具有较大的差异。土地利用后,3种植物的总C呈下降趋势,而N和P整体呈增加趋势,利用程度越高,增加越明显,但也受物种差异的影响。土壤与植物元素含量的相关关系在物种间具差异性,土壤与柽柳和花花柴两种植物营养之间相关性非常低。3种植物的N和P之间具有显著相关性。塔克拉玛干沙漠南缘区域植物普遍缺少N素,土地利用在一定程度上缓解这种N素缺乏。随着荒漠绿洲过渡带利用强度的变化,预计过渡带植被的化学计量将发生不同的改变。  相似文献   

7.
There is rapidly growing national interest in grazing lands’ soil health, which has been motivated by the current soil health renaissance in cropland agriculture. In contrast to intensively managed croplands, soil health for grazing lands, especially rangelands, is tempered by limited scientific evidence clearly illustrating positive feedbacks between soil health and grazing land resilience, or sustainability. Opportunities exist for improving soil health on grazing lands with intensively managed plant communities (e.g., pasture systems) and formerly cultivated or degraded lands. Therefore, the goal of this paper is to provide direction and recommendations for incorporating soil health into grazing management considerations on grazing lands. We argue that the current soil health renaissance should not focus on improvement of soil health on grazing lands where potential is limited but rather forward science-based management for improving grazing lands’ resilience to environmental change via 1) refocusing grazing management on fundamental ecological processes (water and nutrient cycling and energy flow) rather than maximum short-term profit or livestock production; 2) emphasizing goal-based management with adaptive decision making informed by specific objectives incorporating maintenance of soil health at a minimum and directly relevant monitoring attributes; 3) advancing holistic and integrated approaches for soil health that highlight social-ecological-economic interdependencies of these systems, with particular emphasis on human dimensions; 4) building cross-institutional partnerships on grazing lands’ soil health to enhance technical capacities of students, land managers, and natural resource professionals; and 5) creating a cross-region, living laboratory network of case studies involving producers using soil health as part of their grazing land management. Collectively, these efforts could foster transformational changes by strengthening the link between natural resources stewardship and sustainable grazing lands management through management-science partnerships in a social-ecological systems framework.  相似文献   

8.
甄莉娜  刘丽珍  牛艳  李侠  李朕  吴娜  王润梅 《草地学报》2022,30(8):2009-2018
为探讨不同植物类型对煤矸石山丛枝菌根(Arbuscular mycorrhiza, AM)真菌群落的影响,本研究通过高通量测序的方法,调查了禾本科、菊科、豆科和藜科植物根际土壤的AM真菌群落结构及多样性,以期为煤矸石山生态修复中植物种类的选择提供理论依据。结果表明:4科植物共获得球囊菌门(Glomeromycota)OTU数454个,分属于5目7科7属41种,禾本科和藜科植物的OTU数量较多。禾本科AM真菌α多样性中的Chao1指数和Shannon指数最高,藜科组成较为单一,豆科植物根际土壤菌群多样性较低。RDA分析表明,土壤有机质和pH值对AM真菌群落影响作用较大,不同植物AM真菌生态网络关系差异显著,禾本科和黎科植物网络连接密集程度更高且核心物种组成更丰富。研究认为:煤矸石山恢复初期,不同科植物根际AM真菌群落多样性不同,禾本科植物通过与不同种类AM真菌形成良好的共生关系,促使其在煤矸石山恢复早期占据优势地位。  相似文献   

9.
在气候变化和过度放牧影响下,高寒草地退化日趋严重。当前,围栏封育作为退化草地生态恢复的主要措施之一,其对植物功能性状和生理过程影响的研究相对较少。以藏西北荒漠草原植物为对象,选取植物叶片碳(LCC)和氮含量(LNC)及稳定同位素组成(δ13C和δ15N)来表征植物水分利用效率(WUE)和氮素利用效率(NUE),以期探明围栏封育对高寒荒漠草原植物WUE和NUE的相对影响。结果表明:1)高寒荒漠草原不同功能群植物间LCC、LNC、δ13C和δ15N存在差异;2)在植物群落和功能群水平上,围栏封育对LCC、LNC、δ13C和δ15N均无显著影响;3)土壤含水量和pH值是影响荒漠植物叶片δ13C的主要因子,表明植物内在WUE主要受土壤因素的调控。生长季气温是影响叶片δ15N的主导因子,表明气候条件是影响藏西北荒漠草原生态系统氮循环的主导因素;4)荒漠草原植物WUE和NUE之间无明显权衡关系。综上所述,短期围栏封育并不会显...  相似文献   

10.
This paper was prepared in response to a paper prepared by Vetter (in this issue) that addressed the issue of policy development related to sustainable management of rangelands. In line with the sentiments of Vetter, policies are understood to guide the allocation of resources. The important contribution that livestock make to rural livelihoods is well recognised and strengthening crop–livestock interactions is seen as an effective way of improving livestock productivity while generally being understood as an effective way to increase agricultural production so as to meet the growing needs of the global population. The use of crop residues by livestock is one specific linkage that offers opportunities, but this could be maximised by increasing the yield and quality of the residues. One key challenge to strengthening crop–livestock interactions is the extent to which arable lands are being abandoned. Efforts need to be made to reverse this situation, which requires a range of technical and social/institutional interventions. Although some policy documents refer to integrated systems and alternative cropping practices, there is limited evidence that this in fact is happening on the ground. Policy needs to support crop–livestock interactions more actively so that on-farm research with farmers, as is happening in Msinga, becomes more widespread.  相似文献   

11.
培育措施对高寒草甸草原植物多样性和生产力的影响   总被引:1,自引:0,他引:1  
以植物群落特征和根系生物量为主要指标研究了高寒草甸草原对封育(E)、封育+灌溉(EI)、封育+灌溉+施肥(EIF)、封育+灌溉+施肥+补播(EIFR)和全年连续放牧(CG)的响应,以期为该区草地恢复、保护和管理提供支持。结果表明:与CG和E相比,各培育措施均增加了各功能群植物的高度和群落地上、地下生物量,提高了禾本科植物在草群中的比例,垂穗披碱草(Elymus nutans)和冷地早熟禾(Poa crymophila)等优质牧草的重要值显著增加,杂类草植物的重要值降低,其中以EIFR效果最为显著;各培育措施均不同程度的提高了群落物种多样性指数,其中EIF显著高于其他处理;各培育措施不同程度降低了地下与地上生物量比。说明合理选择和组合应用不同培育措施是提升退化高寒草甸草原生产力和有效恢复草地生态的重要手段。  相似文献   

12.
Economic impact of poisonous plants on the rangeland livestock industry   总被引:1,自引:0,他引:1  
Poisonous plants on rangelands cost producers and consumers upwards of $250 million annually in the U.S. These costs are attributable not only to livestock deaths and diminshed productivity related to plant poisoning, but also to the management costs associated with usage of forage in areas infested with poisonous plants. At present, even relatively small losses from plant poisoning can cause financial and economic impacts that threaten range enterprises, particularly those using public lands.  相似文献   

13.
Plateau pikas (Ochotona curzoniae) often clip tall plants near active burrow entrances to detect and avoid predators. This clipping behavior influencing plant communities near active burrow entrances has not been well documented. A field experiment was conducted to investigate the effects of this clipping behavior on plant communities across three sites in the Qinghai-Tibetan Plateau by comparing plant communities near active burrow entrances with communities near abandoned burrow entrances. This study showed that the clipping behavior decreased plant community height and increased plant cover and species richness of the community and had no effect on plant community biomass across three sites or at each site. This study further showed that clipping behavior decreased the plant biomass of the graminoid group and had no effect on the plant species richness of the graminoid group, whereas it increased the plant biomass and plant species richness of the forb group across the three sites or at each site. These findings suggest that a general pattern concerning the effect of the clipping behavior can increase plant species richness and decrease the grazing quality of alpine meadows near active burrow entrances.  相似文献   

14.
Changes in soil and vegetation due to livestock grazing are occurring in arid lands throughout the world. The most extreme cases result in desertification, which is seen as largely irreversible, because of altered soil properties. To understand better how long-term livestock removal affects soil properties and vegetation, we compared water-infiltration rates, soil bulk density, and perennial grass cover inside and outside a long-term livestock exclosure in an arid grassland site in southeastern Arizona, United States. The site had not been desertified at the time of this study. Exclusion of livestock for 40 yr was associated with lower bulk density and higher water infiltration in both the dry and wet seasons. Perennial grass cover was higher and two native grasses, Eragrostis intermedia and Bouteloua hirsuta were significantly more common (P < 0.05) in the ungrazed area. These findings parallel our results from a desertified site and suggest that changes in soil physical properties associated with long-term livestock removal are not an artifact of desertification and can take place in a system that has remained in a grassland state. Our data suggest that, although significant changes in species composition have occurred, this grassland is relatively resilient to substantial changes in soil physical properties.  相似文献   

15.
通过2年的连续放牧试验,采用比较样地法,调查了不同放牧强度对环青海湖高寒草原生物多样性和生产力的影响,并探讨了植物物种多样性与草地生产力之间的关系,为高寒草原的合理利用提供基础资料。结果表明:物种丰富度和多样性指数随放牧强度的增加基本呈单峰变化,即在中度放牧下多样性最高,重度放牧下群落物种丰富度、多样性指数和均匀度指数均表现为最小;群落生产力随放牧强度的增加而降低(P<0.05);莎草科地上生物量差异不显著,禾本科和豆科生产力降低(P<0.05),杂类草生物量有增加趋势;禾草和豆科比例减小,莎草和杂类草比例增加;草地生产力与Simpson多样性指数和Alatalo均匀度指数呈显著的单峰函数关系(R2=0.910, P=20.027; R2=0.953, P=20.010),结合Simpson多样性指数和Alatalo均匀度指数才能更好地反映维持草地生产力水平的多样性指标。放牧强度是影响群落物种多样性和生产力及其关系的重要因素。  相似文献   

16.
Grazing lands and their management in livestock systems are a matter of special importance in the search for sustainability. Socio-economic and ecological objectives should be considered jointly in considering livestock production. In addition to the general issues of biodiversity and habitat preservation, the challenges for their management vary according to the regional conditions. In Southern European environments, where the past changes in livestock farming have led to a general decrease in their use, the questions under study are how to find ways to meet the threats to landscape amenity, biodiversity, the sustainability of local animal feeding resources and the rural population. Grazing lands and their management is also an important target of EU agri-environmental policy. The multifunctional use of this land, which is currently sought, reinforces the need for animal scientists to consider the use and management of grazing lands in reference not only to the techno-economical efficiency of animal feeding systems but also in reference to the long-term (e.g. biodiversity change) and at larger spatial scales (for example the landscape and watershed). An overview of the current challenges attached to grazing lands and their management in livestock farming systems in South European environments, an understanding of the ways to jointly meet production objectives and the realisation of sociological and ecological functions is presented.  相似文献   

17.
为了解氮素沉降对草地群落植物生长策略和群落组成的影响,通过长期(2009-2012年)氮素添加野外控制试验,研究了黄土高原天然草地禾本科植物长芒草(Stipa bungeana)、赖草(Leymus secalinus),豆科植物达乌里胡枝子(Lespedeza davurica)以及菊科植物阿尔泰狗哇花 (Heteropappus altaicus) 4种植物在不同施氮水平下叶片比叶面积(SLA)和物种重要值(IV)的变化特征,并探讨了氮素添加对各种植物叶片SLA和物种重要值影响的内在联系.结果显示:沿施氮水平,禾草科植物长芒草和赖草叶片SLA增加幅度较小、物种重要值整体上呈现逐渐增加的趋势,非禾草科植物阿尔泰狗娃花和达乌里胡枝子叶片SLA增加幅度较大,物种重要值整体上呈降低的趋势,施氮对禾草科植物更有利;各物种的重要值与叶片SLA之间无相关关系;物种重要值随着氮素添加量增加所产生的变异系数与该物种在群落中的重要值大小成显著负相关.表明在干旱贫瘠环境中,植物叶片SLA保守性强、可塑性低;氮素沉降对禾草科植物更有利.  相似文献   

18.
侵染禾本科植物的麦角菌Claviceps sp.不但会引发植物的麦角病造成作物减产,还会引起人和牲畜的中毒。在新疆中部和青海东部部分地区,发现牲畜喜食的3族5属的牧草发生了麦角病,局部地区发病率高达65%,病株上还有瓢虫、丽蝇以及蚂蚁等昆虫活动。研究从5属6种禾本科发病植物上获得了18个分离菌株,观察了分离菌株的菌落形态和生长速度、孢子形态和大小等特征。这些培养特征及形态特征和麦角菌属真菌的无性世代麦角蜜孢霉属Sphacelia真菌类似。通过研究这些分离菌株对农药的敏感性,发现多菌灵对该菌有明显的抑制作用。禾本科植物的麦角病在旅游区-牧区大范围地发生值得注意。  相似文献   

19.
20.
An assessment of nonequilibrium rangeland dynamics was conducted in the Aru basin, a semiarid site located in the very dry northwest part of the Chang Tang Nature Reserve, Tibet, China. A grazing gradient approach was used to examine the effects of different livestock grazing intensities on vegetation, providing data to determine if plant–herbivore interaction has been a major structuring force of the plant community and thus to indicate what type of dynamic might apply in the study area. No significant differences were found between a highly grazed site and a lightly grazed site in vegetation cover, standing biomass, and Shannon–Wiener species diversity index of total, graminoid, forb, and tomtza (Oxytropis glacialis Benth. ex Bunge) functional groups, with the exception that tomtza coverage was significantly higher at the highly grazed (1.04%) than at the lightly grazed site (0.02%). Grazing intensity alone did not explain a significant amount of variation in the plant species data. These results indicate that a dominance of nonequilibrium dynamics appears to be the case in the basin, probably one of the least-arid sites in the northwest Chang Tang region of the Tibetan Plateau. Thus, opportunistic livestock management strategies adapted to variable vegetation production from year to year, rather than the setting of a rigid stocking rate that assumes a stable carrying capacity, is probably the most plausible approach for managing livestock and its relationship to biodiversity values in this region.  相似文献   

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