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在广泛调查的基础上,对黄河源头区天然草场中的高寒草原、高寒灌丛、高寒沼泽与水生植被、高寒沼泽草甸、高寒草甸、高山垫状植被、高山冰缘和流石坡稀疏植被等主要草场植被类型的分布范围、群落结构和组成及其年轻性、脆弱性、敏感性、原始性、典型性等特点进行了论述,最后提出了对黄河源区天然草场植被保护的意见。 相似文献
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黄河源区天然草场的植被类型及其特点 总被引:1,自引:0,他引:1
在广泛调查的基础上,对黄河源头区天然草场中的高寒草原、高寒灌丛、高寒沼泽与水生植被、高寒沼泽草甸、高寒草甸、高山垫状植被、高山冰缘和流石坡稀疏植被等主要草场植被类型的分布范围、群落结构和组成及其年轻性、脆弱性、敏感性、原始性、典型性等特点进行了论述,最后提出了对黄河源区天然草场植被保护的意见。 相似文献
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观测了浙江要种山羊的浙江低山灌丛草场从丘陵山地草丛草场的海拔、光、热、水等气象因子,植被及牧草质量等生态因素影响下的采食行为和繁殖性能。结果表明,除遗传因素外,草场的植被类型与牧草的营养水平是影响山羊繁殖力的基本因素;丘陵山地草丛草场的地势、植被种类等生态因素比低山灌丛草场更适合杂种山羊的放牧,使其有较大的日采食量与营养总摄入量;在光、热、水等气候因子同时直接作用下,丘陵山地草丛草场的杂种山羊性成 相似文献
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毛乌素沙地高等植物资源 总被引:8,自引:0,他引:8
为了解禁牧和退耕后毛乌素沙地的植被状况,2002-2004年在查阅相关资料和野外调查的基础上,对沙地高等植物资源进行统计与分析。结果表明:毛乌素沙地的高等植物共有1106种,分属于98科420属;主要科有菊科、禾本科、豆科、蔷薇科和藜科;主要属有蒿属、黄芪属、葱属、柳属、杨属;主要种有油蒿、沙竹、牛心朴子、沙柳和乌柳;植被类型主要有草原植被、草原和荒漠灌丛、沙生植被、草甸植被、盐生植被、沼泽和沼泽性植被、水生植被,其中沙生植被占主导地位,其次为草甸植被;植物群落主要有油蒿群落、油蒿—柠条群落和沙柳、乌柳、沙棘组成的“柳湾”;简述了毛乌素沙地的植被特征,提出灌木应为该区植被建设的主要物种,加强灌、草、乔之间的结合。 相似文献
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我区生态平衡失调,由来已久,特别是解放后,由于“左倾”政策干忧,人口失控和自然灾害频繁,造成草场面积不断缩小,超载过牧,草地沙化、碱化、植被退化日趋严重。根据1983年草场资源调查,全区有天然草场2454.8万亩(合灌丛草场),其植被 相似文献
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通过研究皖北石灰岩山地生态系统的植被群落,分析不同植被恢复群落的组成、结构、多样性和生活型组成,进而阐明石灰岩山地生态系统植被恢复模式对群落结构特征以及植物物种多样性的影响。结果表明:研究区有54种植物,隶属26科54属。侧柏(Platycladus orientalis)+构树(Broussonetia papyrifera)人工混交林有植物种类16科26种,分别占总数的61.5%和48.1%。酸枣(Ziziphus jujuba var.spinosa)+牡荆(Vitex negundo var.cannabifolia)灌丛和荩草(Arthraxon hispidus)+牡荆草灌丛植物种类分别为32和33种,分别占调查总物种数的59.3%和61.1%。不同植被恢复群落生活型也有差异。侧柏+构树人工混交林群落高位芽植物占优势,而酸枣+牡荆灌丛和荩草+牡荆草灌丛则以地面芽植物所占比例较大。分析表明,多样性指数、均匀度指数和优势度指数均表现为侧柏+构树混交林>酸枣+牡荆灌丛>荩草+牡荆草灌丛,但物种丰富度表现为荩草+牡荆草灌丛>酸枣+牡荆灌丛>侧柏+构树混交林。Sörensen较高值出现在酸枣+牡荆灌丛与侧柏+构树混交林和荩草+牡荆草灌丛之间,侧柏+构树混交林与荩草+牡荆草灌丛Sörensen多样性值较低。研究结果表明,石灰岩山地独特的地貌特征和人工植被恢复对植物群落组成、多样性及其生活型组成产生重要影响。 相似文献
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1986年,乌兰察布盟开展了低山丘陵区人工灌丛草场建设,经过八年试验,示范及大面积推广,至今已建成9.39万hm^2,本文对5个类型的灌丛草场进行盖度,高度,产量及群落结构进行调查分析,表明,利用柠条,羊柴,沙打旺,陈少等适应当地生态条件的有饲用价值的灌木,半灌木,多年生牧草建立的人工灌丛草场,不但可解决饲草供给的不足,而且,是保持水土,防风固沙,改善生态环境的有效途径。 相似文献
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新疆草地荒漠化过程及驱动因素分析 总被引:7,自引:0,他引:7
草地作为新疆生态环境的主体,其荒漠化的发生与发展关乎新疆的生态安全及生态环境质量。本研究通过对新疆草地生态系统分布规律、特征及利用现状的分析,从草地荒漠化过程及其与其他生态系统的相互关系入手,探讨自然因素和人为因素对草地荒漠化的影响。结果表明,1)新疆草地荒漠化过程分为两种类型,Ⅰ型为低山、平原荒漠类型草地的沙化、盐碱化和退化过程,Ⅱ型为山地草地类型的退化过程;2)在人类活动和水文环境变化的综合作用下,草地与耕地、沙地、林地、湿地和社区在荒漠化过程中可进行相互转化;3)地形地貌、气候和土壤等自然因素是草地荒漠化发展的背景条件,为草地荒漠化的发展提供了物质基础,气候变化是南疆和东疆盆地草地荒漠化的主要驱动因素之一;4)水资源不合理利用是各流域中下游草地荒漠化的主导因素,滥垦滥挖是绿洲周边草地荒漠化的直接导因,放牧场、割草场荒漠化的主要导因是长期超载、无序利用及草地建设投入严重不足。新疆草地荒漠化形成的驱动因素不仅具有多因素性、地域性的特点,而且具有交叉和叠加的综合特点和多营力综合作用特征。 相似文献
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为探索半干旱沙化荒漠地区牧草生态系统重建与保持技术,在甘肃省张掖典型沙化撂荒地,采用固沙保土有机肥与草原3号杂花苜蓿相结合的方法进行野外试验。结果表明:在半干旱沙化荒漠地,草原3号杂花苜蓿(Medicago variacv.caoyuan No.3)条播后,随即喷施50~60倍的具有黏结、吸湿、保水功能的"固沙保土有机肥"溶液90~120 t/hm2,同时完成浇水、施肥、铺膜(自然形成的可降解生态地膜)3道工序,基本满足草原3号杂花苜蓿发芽生长所需的水分和养分,从而初步形成牧草生态系统。 相似文献
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以青海省治多县轻度沙化和重度沙化草地为研究对象,对其植被群落特征和土壤理化性状进行了调查。结果表明:随着草地沙化程度的加剧,草地植物群落结构(如群落优势种等)发生了明显的变化,群落盖度、生物量均明显下降(P0.01),植被高度反而上升(P0.01)。而通过保护与综合治理,重度沙化草地物种数、多样性指数、均匀性指数却大于轻度沙化草地。同时,随着草地沙化程度的加剧,土壤养分在0~15cm水平上明显下降(P0.01),而在15~30cm水平上变化不明显。 相似文献
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Eva Straková Pavel Suchý Ivan Král David Zapletal Ivan Herzig 《Journal of Equine Veterinary Science》2013
Ten samples of plant vegetation and 10 samples of fresh excrement were taken from the same pasture area. The excrement were collected from 10 2-year-old Old Kladruber horses that received the pasture vegetation daily. The apparent digestibility of nitrogen and amino acids in pasture vegetation was determined by using the acid-insoluble ash marker method. In comparison with excrement, the pasture vegetation contained higher levels of Ser, Ala, Leu, and His and higher levels of Pro (P ≤ .01), Met (P ≤ .01), and Arg (P ≤ .05). The mean level of Ile in pasture vegetation was lower than in excrement (P ≤ .05). The apparent digestibility of amino acids from pasture vegetation was high for Pro and Met (86.75 and 89.39%), moderate for Ser, Ala, Leu, His, and Arg (68.61%-76%), and low for Asp, Thr, Glu, Gly, Val, Leu, Tyr, Phe, and Lys (56.15%-66.03%). The digestibility of lysine and Ile was relatively low (56.39% and 56.15%, respectively). The total content of nitrogen per dry matter was 10.98 ± 2.46 g/kg for pasture vegetation and 12.12 ± 2.38 g/kg for excrement, whereas the content of protein nitrogen was 7.20 ± 0.25 g/kg and 6.89 ± 0.21 g/kg of dry matter in pasture vegetation and excrement, respectively. This means that only 65.55% and 56.90% of N is bound in proteins in pasture vegetation and excrement, respectively. Non-protein nitrogen accounts for 34.45% in pasture vegetation and for 43.10% in excrement. 相似文献
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Daniels MJ Lees JD Hutchings MR Greig A 《Veterinary journal (London, England : 1997)》2003,165(3):1-257
Grazing herbivores avoid grass swards contaminated with faeces as the ingestion of faeces is a common route of micro- and macro-parasite transmission. The recent novel finding that herbivores do not avoid grass swards contaminated with rabbit faeces suggests that disease risk posed to herbivores by rabbits is determined by rabbit ranging and excretory behaviour. Using as a case study rabbits and the risk Mycobacterium avium sub-species paratuberculosis (M. a. paratuberculosis) poses to cattle, the interaction between rabbits and grazing pasture was studied on an infected farm in the east of Scotland in spring and autumn 2000. Radio telemetry, burrow surveys and faecal pellet count data were collected on two areas (Areas 1 and 2) of the farm with different habitat mosaics, to study the potential effects of season and habitat on the spatial distribution of rabbits faeces and thus disease in the environment. Twenty one rabbits were radio tracked and a total of 902 fixes collected. Mean home range sizes (100% minimum convex polygons) were between 2.0 and 7.1 ha per rabbit per season. Home ranges were significantly larger in spring, and in Area 1 which had more moor and woodland and less rough pasture. Rabbits used rough pasture most in Area 1 and gorse scrub in Area 2. In both areas, significantly more burrows were located in gorse scrub than in any other habitat. Most faecal pellets were deposited on the moorland habitat of Area 2 in autumn. In habitats to which grazing livestock had access, the mean rate of faecal deposition was 8571 pellets per ha per day. The greatest risk of disease transmission occurred in habitats of poor grazing quality (e.g., gorse scrub) which were used by rabbits for burrowing and thus contained high concentrations of faeces. The findings of the study are discussed in relation to management practices aimed at reducing disease risk to livestock, including the fencing of scrub and the reduction of rabbit population size to prevent expansion of rabbit burrows from scrub into grazing pastures. 相似文献
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在荒漠生态系统中,以人工灌丛进行植被恢复与重建是土地荒漠化防治最有效、最经济、最持久、最稳定的措施之一。土壤动物是荒漠生态系统土壤生物的重要组分,在物质循环、养分流动和信息传递中扮演着重要角色。荒漠灌丛和土壤动物互相作用能够促进灌丛“肥岛”演变,有利于灌丛生态功能发展和退化生态系统有效恢复。降水变化条件下,基于“荒漠灌丛和土壤动物关系”这一核心问题,在总结荒漠灌丛分布特征、荒漠灌丛和土壤动物分布关系的基础上,分析了荒漠灌丛土壤动物分布对降水变化的响应规律及内在机制。在未来全球变化条件下,从荒漠灌丛土壤动物对地上的反馈效应、研究方法与先进技术应用及荒漠灌丛土壤动物多样性与生态系统服务功能方面,探索了荒漠生态系统中荒漠灌丛土壤动物研究中应重点关注的几个科学问题,为荒漠生态系统生物多样性保护、植被建设及响应气候变化管理提供了科学依据。 相似文献