Saltbush Transects, Koonamore Vegetation Monitoring Project (1925-present)

The TGB Osborn Vegetation Reserve (or Koonamore Vegetation Reserve (KVR)) is a protected area on Koonamore Station which has been fenced off from grazing since the mid 1920's. In 1925, Professor Theodore George Bentley (TGB) Osborn and his colleagues established a vegetation reserve by fencing off 400 ha of a badly overgrazed portion of the Koonamore station to study the process of recovery of vegetation in the arid zone of South Australia after the removal of grazing pressure. The fence was established to initially keep sheep and later also rabbits from the reserve and allow vegetation regeneration. The resulting long-term vegetation monitoring project at Koonamore is now over 80 years old, making it one of the longest-running monitoring series of its type in the world.; Reserve History: In the mid 1920's Professor TGB Osborn and his colleagues extended their interests in ecology and field physiology of vegetation to the arid zone of South Australia. In 1892 Dixon had warned the Royal Society of South Australia of serious degradation of the soils and vegetation resulting from pastoralism and other alien influences in the region. Equally important to the origin of KVR was the new theory of vegetation succession derived from North American work early in the century. Osborn was particularly concerned with the question as to whether overgrazing by domestic and feral herbivores would result in return of the original vegetation via recognisable 'seral' stages, or whether the changes were ?artificial, mere destructions and as such outside the ecologist's proper field?. Although the concepts of 'succession' and the scope of ecology have developed and changed much since that time, nevertheless it was interest in 'succession to climax' that gave the initial impetus to KVR and many other long-term vegetation studies from that time. The theory of vegetation succession gave rise to the permanent charted quadrat as a technique for observing vegetation change. An extensive series of permanent quadrats was set up on KVR and supplemented by a series of fixed photopoints, in order to pursue the first aim. Although some of these were allowed to lapse within five years, many others were sampled more or less regularly, some almost annually up to the present. Several early publications reviewing the progress of vegetation change resulted. Nothing was done towards the second aim but autecological and population dynamics studies are still being carried out, based on KVR and its records. The Bibliography contains a complete listing of research publications arising from work done on the Reserve. Much of the continuity of the earlier records is due to the efforts of Miss Constance Eardley, who while a lecturer in the Department of Botany, organised annual visits of students and staff to take records and maintain KVR. However, after 1950 the rate of sampling had begun to decline and in the mid 1960's ceased altogether for a period of several years. In the 1970's Dr Russell Sinclair reactivated the recording programme and also began a sustained effort at rabbit control. Although the Reserve was originally fenced with rabbit-proof netting, the rabbits were never eradicated and the population has fluctuated greatly with the seasons. Beginning in 1975, numbers have been kept very low by careful annual inspection and control. Since that time there has been marked seedling establishment of several tree and shrub species which showed little previous regeneration. The Reserve records now contain a history of the vegetation over 50 years without sheep grazing followed by over 30 years without significant grazing by either sheep or rabbits. Kangaroos and emus have never been excluded from the Reserve, as they can jump the fence, and their numbers vary with the seasons. The monitoring work at KVR and the curation of its records is continuing under the direction of Dr Sinclair. The Reserve is also used for post-graduate study and complements the arid-zone research interests of Environmental Biology at the Middleback Field Sation near Whyalla.; Site Description: The Reserve is located in the centre of Koonamore Station, a sheep-grazing lease 400 km north-east of Adelaide, South Australia (Lat. 32º07'S, Long. 139º20'E) in predominantly chenopod shrubland with mean annual rainfall of about 200mm. The area consists of a complex of low sand dunes alternating with sand plain and harder loam soils with travertine limestone on the intervening flats. The tree cover is a low open woodland formation. The sand dunes carry Acacia aneura (mulga), A. burkittii and Eremophila spp., the sand plain a dense stand of Casuarina pauper (blackoak, belah), and the harder loam soils a mixed community of Myoporum platycarpum (false sandalwood) and Alectryon oleifolius (bullock bush, rosewood). Understorey shrubs, which also form low chenopod shrubland communities in some areas, include Atriplex vesicaria (bladder saltbush), A. stipitata and Maireana sedifolia (bluebush). Numerous other chenopodiaceous shrubs also occur, and grass and ephemeral herb cover varies with the seasons. Several species of Senna, Eremophila and other shrubs also occur.; Monitoring activities: Some or all of the following monitoring activities are carried out during visits to the TGB Osborn Vegetation Reserve: Vegetation Quadrats, Photopoints, Senna Quadrat (Cassia Corner), Myoporum platycarpum Plants, Saltbush Transects, Senna Populations, Kangaroo Transects, Rabbit Activity Monitoring and Control.; Saltbush Transects: Four point intercept transects were monitored across the eastern and southern reserve boundary to record the spread of <em>Atriplex</em> species into the TGB Osborn Vegetation Reserve. Please use the following URL to access the dataset: http://aekos.org.au/collection/adelaide.edu.au/Koonamore/SaltbushTransects

TGB奥斯本植被保护区（亦称库纳莫尔植被保护区，KVR）是位于库纳莫尔牧场的封禁保护区，自20世纪20年代中期起便实施禁牧围栏管理。1925年，西奥多·乔治·本特利·奥斯本（TGB）教授与其同事将库纳莫尔牧场内400公顷严重过度放牧的区域用围栏圈定，建立该植被保护区，以研究南澳大利亚干旱区移除放牧压力后植被的自然恢复过程。该围栏最初用于阻挡绵羊进入，后续增设了防兔功能，旨在为植被自然恢复创造条件。目前，库纳莫尔地区的长期植被监测项目已持续80余年，是全球同类持续时长最长的监测序列之一。

保护区历史：
20世纪20年代中期，TGB奥斯本教授及其团队将植被生态学与野外生理学的研究方向拓展至南澳大利亚干旱区。1892年，迪克森曾向南澳大利亚皇家学会警示，该区域因畜牧业及其他外来人类活动导致土壤与植被出现严重退化。与库纳莫尔植被保护区（KVR）创立息息相关的另一项重要基础，是本世纪早期源自北美研究提出的植被演替新理论。奥斯本尤为关注一个核心问题：家畜与野生植食动物的过度放牧，是否会通过可识别的“演替阶段”推动原生植被恢复，抑或此类变化属于人为干扰下的单纯破坏，已然超出生态学家的常规研究范畴？尽管自彼时起，“演替”的概念与生态学的研究范畴已发生诸多演变，但正是对“向顶级群落演替”的研究兴趣，为库纳莫尔植被保护区（KVR）以及此后诸多长期植被监测项目提供了最初的研究动力。植被演替理论催生了永久性样方（quadrat）这一用于观测植被动态变化的经典研究技术。研究团队在库纳莫尔植被保护区（KVR）内布设了大量永久性样方，并辅以固定摄影点（photopoint），以推进首个研究目标。尽管其中部分样方与摄影点在五年内便停止了监测，但其余多数仍得到了定期或不定期的采样，部分监测点甚至持续至今日，采样频率近乎每年一次。早期已有多篇综述植被变化进程的研究成果发表。针对第二项研究目标的相关工作尚未正式开展，但基于该保护区及其监测记录的个体生态学与种群动态研究仍在持续进行。本参考文献列表完整收录了依托该保护区完成的所有研究出版物。早期监测记录的连续性很大程度上得益于康斯坦斯·厄德利女士的付出：她时任植物学系讲师期间，定期组织师生到访保护区开展数据记录与设施维护工作。不过1950年后，采样频率开始逐步下降，至20世纪60年代中期更是完全中断了数年。20世纪70年代，拉塞尔·辛克莱博士重新启动了监测计划，并牵头开展了持续的兔害防控工作。尽管保护区最初安装了防兔网，但野兔种群始终未能被彻底根除，其数量随季节波动剧烈。1975年起，通过每年细致的巡查与针对性防控，野兔种群被稳定维持在极低水平。自此之后，多种此前几乎无自然更新的乔木与灌木物种出现了显著的幼苗定植现象。保护区的监测记录现已涵盖了50余年无绵羊放牧、以及其后30余年无绵羊或野兔显著放牧的完整植被变化历史。袋鼠与鸸鹋从未被排除在保护区之外，因其可轻易跃过围栏，其种群数量同样随季节波动。目前，库纳莫尔植被保护区（KVR）的监测工作与记录管理仍在辛克莱博士的指导下持续推进。该保护区同时也用于研究生教学实践，并与位于怀阿拉附近的米德尔巴克野外站（Middleback Field Station）的干旱区环境生物学研究方向形成互补。

样地概况：
该保护区坐落于库纳莫尔牧场的中心区域，该牧场为绵羊放牧租赁用地，位于南澳大利亚州阿德莱德东北400公里处，地理坐标为南纬32°07′、东经139°20′，区域植被以藜科灌丛（chenopod shrubland）为主，年均降水量约200毫米。该区域由低矮沙丘、沙质平原与较坚硬的壤土构成，丘间平地分布有钙华石灰岩（travertine limestone）。乔木层为低矮开阔的林分结构：沙丘上生长有多节相思树（Acacia aneura，俗称穆尔加相思）、伯基特相思树（A. burkittii）以及爱沙木属（Eremophila）物种；沙质平原上为密集的贫木麻黄（Casuarina pauper，俗称黑栎、贝拉木）林；较坚硬的壤土区域则分布有肉果木（Myoporum platycarpum，俗称假檀香木）与薄叶异木患（Alectryon oleifolius，俗称牛轭木、玫瑰木）。下层灌丛在部分区域也形成低矮藜科灌丛群落，包括囊滨藜（Atriplex vesicaria，俗称膀胱滨藜）、具柄滨藜（A. stipitata）以及蓝绒藜（Maireana sedifolia，俗称蓝灌丛）。此外还分布有众多其他藜科灌木，草本与一年生草本植被的覆盖度随季节显著变化。番泻决明属（Senna）、爱沙木属（Eremophila）以及其他灌木物种亦有分布。

监测活动：
在到访TGB奥斯本植被保护区期间，会开展下述部分或全部监测活动：植被样方监测、固定摄影点监测、番泻决明属样方（决明角，Cassia Corner）监测、肉果木植株监测、滨藜样带监测、番泻决明属种群监测、袋鼠样带监测、野兔活动监测与防控。

滨藜样带：
研究人员在保护区东部与南部边界布设了4个点截法样带，以记录滨藜属（Atriplex）物种向TGB奥斯本植被保护区的入侵扩散情况。请通过以下URL访问该数据集：http://aekos.org.au/collection/adelaide.edu.au/Koonamore/SaltbushTransects