Vom „armen Schwein“ zur „Rampensau“ Stachelschweinhaltung (Hystrix indica Kerr, 1792) im Naturschutz-Tierpark Görlitz-Zgorzelec

The modification of the porcupine enclosure with enlargement of the area and creation of various levels and structures in combination with a feeding management that involves the visitors has essentially increased the presentation value of porcupines at Goerlitz Zoo. This kind of animal presentation requires a high-quality animal management, which has to take the behavior as well as the number of visitors into account. The activity of the porcupines has risen notably since the described modifications, which has made these exotic rodents one of the most frequented visitor attractions at the Zoo.     

Acceleration of vegetation succession on eroded land by reforestation in a subtropical zone

Based on field investigations in the East River basin in Guangdong Province, south China, the processes of vegetation development and vegetation succession on bare slopes with high erosion rates are studied. Different reforestation measures have been applied to the slopes, which have resulted in very different processes of vegetation development and succession. On an experimental plot with burned forest but surviving roots, the vegetation restored naturally and quickly because there was little soil erosion. However, in the plots suffering from long-term severe soil erosion, natural vegetation recovery on these barren slopes is very slow. After 26 years, a barren slope has only been partly colonized by poorly developed vegetation composed of heliophilous herbages and scattered shrubs. On the other hand, plantation of some selected wood species on the slope land has dramatically accelerated the vegetation recovery and succession. The plots were reforested with plantation of Acacia auriculiformis in the early 1980s. Twelve years later, the vegetation cover of the artificial forests reached 90% and an understory vegetation community consisting of local species had naturally developed. Reforestation with suitable strategies may control erosion and greatly accelerate vegetation succession in the eroded slope land in the subtropical zones.     

Habitat associations of the Small Red Damselfly (<Emphasis Type="Italic">Ceriagrion tenellum)</Emphasis> (De Villiers) in heathland in southern England (Zygoptera: Coenagrionidae)

The Small Red Damselfly (Ceriagrion tenellum) (De Villiers) (Odonata: Coenagrionidae: Ceriagrion) is classed as vulnerable (Shirt, British Red Data Book, Nature Conservancy Council, Peterborough, UK, 1987) throughout the UK, and is included in certain Local Biodiversity Action Plans (LBAPs) in the south. A large proportion of any Biodiversity Action Plan is concerned with the requirement of conservation and management programmes. In order to guide them, information about the habitat preferences of the species concerned is vital. Detailed habitat information was collected to include a variety of physical parameters particularly vegetation, both in-channel and bankside. The species was found to be primarily associated with in-channel emergent broad-leaved plants, bankside grasses and rushes, and shallow, narrow channels with dark organic substrate. The consequences of these findings are discussed in relation to the conservation and management of C. tenellum.

Competitive effects of herbaceous vegetation on tree seedling emergence,growth and survival: Does gap size matter?

Question: What is the effect of gap size on the seedling emergence, growth and survival of four common tree species in wooded pastures? Location: A pasture in the Jura mountains, Switzerland. Methods: Seeds were sown in a complete three‐way factorial design with eight blocks in May 2003. Each block consisted of a competition treatment (four gap sizes including zero) and a mowing treatment (mown and unmown). Emergence, survival and total biomass of tree seedlings of three species (Picea abies, Acer pseudoplatanus and Fagus sylvatica) were measured. A fourth species (Abies alba) failed to germinate. Results: Gaps had a positive influence on the early stages of tree development for all species. Larger gaps favoured growth and survival more than small gaps. Seedling growth was higher when vegetation around the openings was mown. Mowing the vegetation at gap size zero enhanced both growth and survival compared to unmown vegetation. Mown gaps larger than zero had increased seedling desiccation but decreased seedling predation. Species showed similar trends in their emergence and growth responses to gap size and mowing treatments but for Picea emergence rate was higher and survivorship was lower than for Acer and Fagus. Conclusions: Gap size does matter for tree seedling success but even in more favourable large gaps only a small percentage of seedlings emerged and survived. The effects of gaps on tree seedling establishment are complex as a result of interactions between biotic and abiotic changes caused by gaps.     

Niches of plant populations in mangrove reserve of Qi’ao Island, Pearl River Estuary

Thirty-two 10 × 10 m² quadrats were set up in four mangrove communities for the study of the niches of nine plants with horizontal and vertical resource sequences in Dawei Bay, Qi’ao Island, Zhuhai City. Generally, species diversities of natural mangroves were higher than those of plantations. The diversities decreased along sequence of substrate layer, shrub layer and tree layer in natural mangroves; and were highest on the shrub layer in plantations. At the horizontal resource sequence, the niche breadth varied 0.132–0.896 (B_(sw)) and 0.120–0.693 (B_(L)). The niche breadth of Acanthus ilicifolius and Aegiceras corniculatum were the highest and that of Spartina alterniflora was the lowest. At the vertical resource sequence, the niche breadth varied 0–0.400 (B_(sw)) and 0.333–0.747 (B_(L)). All the niche breadth values were the lowest except those of A. ilicifolius and A. corniculatum. The niche similarity of the populations varied 0–0.746 and 0–1.000 at the horizontal and vertical resource sequences, respectively. A. ilicifolius and A. corniculatum had niche overlap with all plants at the horizontal resource sequence, while the introduced Sonneratia caseolaris and Sonneratiaapetala had no such overlapping between six and five plants in the community, respectively. At the vertical resource sequence, A. ilicifolius and A. corniculatum had niche overlapping with all the populations. The more niche overlapping existed among the other populations. The results indicated that, currently, the mangrove plantation in Qi’ao Island had a simplex structure and composition of species. The status of plant populations’ niche was determined by the species selected and structure of afforestation. It is suggested to create forest gaps artificially and introduce Kandelia obovata saplings to reverse its current status of lower niche breadth, facilitate natural regeneration and spreading of A. corniculatum and A. ilicifolius, and accelerate the restoration process of natural mangrove. Simultaneously, the species matching and planting methods of mix stands should be emphasized in the future.     

大明山中山植被恢复过程植物物种多样性的变化

对大明山中山退化生态系统植被恢复过程植物物种多样性的发展研究表明：大明山中山植被恢复过程物种数量的增减总是伴随着阳性先锋物种的衰退和中生性顶极种的发展。恢复过程中植物物种数量呈前期（２～２０年）迅速增加,中期（５０～６０年）减少,后期（１５０年以上）维持一定水平的发展趋势。中山区退化生态系统的植被恢复是朝着地带性植被类型的方向发展的,此过程可以不经过马尾松先锋林阶段,而直接进入以阔叶树种为优势的先锋群落。因此,大大缩短了中山山地退化生态系统植被向中生性顶极植被恢复的进程。     

Changes in soil properties and vegetation following livestock grazing exclusion in degraded arid environments of South Tunisia

In this study, characteristics of vegetation and soil properties under continued grazing and exclusion of livestock for 6 and 12 years were examined in a degraded Stipa tenacissima steppe in South Tunisia.     

岷江上游干旱河谷西康扁桃灌丛生长繁殖特征

以西康扁桃（Amygdalus tangutica（Batal.） Korsh.）为材料,在岷江干旱河谷四川省阿坝藏族羌族自治州茂县至松潘段设置47个调查点进行该物种的自然分布调查;选取4个典型分布点,随机选择20株灌丛,测定西康扁桃的年龄、基径、高度、冠幅等生长指标以及结实量、结实重量等特征指标;并设置5个4 m×6 m的灌木样方,调查西康扁桃的群落结构与物种组成情况。结果显示：西康扁桃广泛分布于岷江上游干旱河谷,并在松潘县南部安宏乡形成优势群落,群落主要由灌木及多年生草本植物组成,物种丰富度较高（43~55种/24 m²）;西康扁桃当年结实量较小,平均值为（8.83 ±2.25）粒/丛;灌丛平均萌生枝数为（7.38 ±0.46）枝/丛,其中25.68%的萌生枝处于5~10 a的年龄阶段,而果重/枝叶重仅为（0.69 ±0.16）%,表明其结实能力较低,主要依靠产生萌生枝维持种群稳定;各生长与结实参数关系密切,灌丛年龄、高度是影响结实量的主要因素。研究结果表明,西康扁桃广泛分布于岷江上游干旱河谷内,灌丛有性繁殖贡献率较低,依靠无性繁殖维持群落稳定,亟需开展资源保护。     

黄土高原植被恢复的水分生态环境研究

水分是制约黄土高原地区植被恢复与生态环境重建的决定性因子,在分析现有关于该区植被建设中的水分生态环境的各项研究的基础上,从水资源,土壤水分背景,土壤水分动态,土壤干层,土壤水分的林草生产力,水分性质分区,林草对策等7个方面,对黄土高原的土壤水分环境进行了阐述,针对该问题的研究现状,指出其中存在的问题,并对今后的研究进展了展望。     

Changes in a salt-marsh vegetation as a result of grazing and mowing — A five-year study of permanent plots

Summary Part of a salt-marsh (32 ha), ungrazed from 1958 until 1971, was grazed again from 1972 onwards with young cattle (1.3–1.7 per ha, May–October). In five vegetation types management experiments, including doing nothing (control). June mowing, August mowing, June and August mowing, all in combination or not in combination with grazing have been started with the objective to compare annually their effects on the vegetational structure and composition by means of permanent plots (2×2 m).Thirteen years (1958–1971) after the grazing had ceased the vegetation types of Festuca rubra/Armeria maritima, Artemisia maritima, Juncus maritimus and Elytrigia pungens hardly changed anymore. The vegetation type of Festuca rubra/Limonium vulgare, changed considerably. The experiments showed rather specific effects during the period 1971–1975 for each type of vegetation. Changes in the Festuca rubra/Armeria maritima vegetation were small and gradually under all treatments. Changes in The Artemisia maritima, Festuca rubra/Limonium vulgare and Juncus maritimus vegetation types were rather great under the different grazing treatments, the changes being abrupt and especially taking place in the third and fourth year of the experiments. The Elytrigia pungens vegetation showed large changes under all treatments, except the control plot, whereas these changes were abrupt, particularly occurring in the first and second year of the experiments. The study is continued.Nomenclature of taxa follows Heukels & van Ooststroom (1970), that of syntaxa Westhoff & den Held (1969).Contribution to the Symposium of the Working Group for Succession research on permanent plots of the International Society for Vegetation Science, held at Yerseke, the Netherlands, October 1975.Thanks are due to Prof. Dr. D. Bakker for his interest in the present study and his critical reading of the text, and to Drs D.C.P. Thalen for critical reading and correction of the English text. Thanks are also due to the students who analyzed the permanent plots: M. van der Duim and F. Prins (1971), M. van der Duim (1972), R. Schwab and T. Schwab-Vos (1973), and G. Allersma (1974, 1975).     

植被生态系统恢复及其在华南的研究进展

介绍了恢复生态学常用的理论,并指出恢复生态学研究大多涉及植被生态系统恢复。植被恢复的目标就是要恢复植被的合理结构、功能和动态过程,从而为人类提供生态系统服务。植被恢复可以把区域的地带性植被生态系统作为参考生态系统,但目前的植被恢复工作绝大部分只是恢复了植被生态系统的部分组成、结构和功能。植被生态系统恢复研究主要从退化的原因与过程、恢复的过程与机理,以及从生境恢复、种群恢复、群落恢复、生态系统和景观恢复等不同尺度上的恢复开展。在介绍华南地区的植被生态系统现存问题的基础上,对华南地区开展的植被生态系统恢复,尤其是华南植物研究所(园)开展的植被生态系统恢复研究进行了介绍。最后,提出了华南地区植被生态系统恢复的方向及发展趋势。