Species Richness and Habitat Use of Small Carnivores in the Arusha National Park (Tanzania)

The carnivore community of Arusha National Park, Tanzania, was monitored using live trapping and diurnal and nocturnal visual counts and recording of tracks and signs along line transects. Nine carnivore species were recorded. Hyena (Crocuta crocuta), the most common large species, leopard (Panthera pardus) and African civet (Civettictis civetta) were detected along line transects, while the smaller species were counted and/or captured. Mungos mungo, Galerella sanguinea, and Genetta maculata were the most prevalent at transect counts, while G. sanguinea, Bdeogale crassicauda, and G. maculata were most frequently captured. Ichneumia albicauda and Ictonyx striatus were captured at only a single site. Carnivores selected natural habitat types, multilayered forest, open shrubs and herbaceous savannah, and were absent, or tended to avoid disturbed (man-made) habitats. Species of which sufficient data were gathered seemed to behave as habitat generalists (C. crocuta, G. sanguinea, G. maculata, M. mungo and I. striatus). The need for more detailed studies on small carnivore ecology and the importance of smaller protected areas for their conservation are discussed.     

Sward height and bite size affect the functional response of barnacle geese Branta leucopsis

Intake rate, the rate in which herbivores can process their food, is presumed to be an important factor in habitat selection down to the scale of the foraging patch. Much attention has been given to the selection of swards of high nutritional quality, but much less has been given to the influences of sward structure on patch selection in small herbivores. In this study we tested the effects of sward density and height on the functional foraging response of barnacle geese, Branta leucopsis. The functional response curve for herbivores describes how intake rate is affected by food availability. We conducted feeding trials to determine intake rate and bite size of barnacle geese on experimentally manipulated swards. Results indicate that intake rate is mainly dependent on sward height and that there is a strong correlation between bite size and intake rate. Sward density does not influence the rate of food consumption; it is, however, a crucial parameter affecting potential total yield. We conclude that bite size is the crucial parameter influencing intake rate. Bite size is explained both by sward height and individual differences in bill morphology. Furthermore, intake rate seems to be dependent on the physical structure of the grass species consumed.     

Conditioning ewes and lambs to increase consumption of spotted knapweed

Spotted knapweed (Centaurea maculosa Lam.) is an invasive plant that alters species composition and grazing value of rangelands in the northwestern United States. The spread of invasive plants may be reduced by using livestock as a biological control. We determined if mature ewes and their lambs (n = 34 ewe/lamb pairs) consume more spotted knapweed when ewes and/or lambs are conditioned to fresh-cut spotted knapweed. Ewe/lamb pairs were randomly assigned to one of four conditioning treatments: ewes and lambs not conditioned to spotted knapweed (N), conditioned ewes with non-conditioned lambs (E), non-conditioned ewes with conditioned lambs (L), or conditioned ewes and lambs (both—B). Then, ewes and lambs were observed together for 5 days (Trial 1); 11 days later, lambs were observed for 4 days without their mothers (Trial 2). During conditioning, intake by conditioned and non-conditioned ewes and lambs varied over time (as-fed basis, treatment by day interaction; ewes P = 0.03; lambs P = 0.05). Overall, non-conditioned lambs (N, E) consumed more than conditioned lambs (L, B; P = 0.02). In Trial 1, N ewes consumed similar amounts of spotted knapweed and bromegrass (Bromus inermis Leyss.) as the E, L, and B ewes (P = 0.67). E ewes spent more time eating spotted knapweed than L ewes (P = 0.001), and E ewe/lamb pairs consumed more spotted knapweed than L ewe/lamb pairs (P = 0.02). In Trial 2, N lambs consumed less spotted knapweed than E, L, and B lambs (P = 0.06). L lambs consumed more than E lambs (P = 0.007). Conditioning ewes, lambs, or ewes and lambs did not increase time spent eating spotted knapweed when both grazed together in a drylot, but conditioned lambs, without their mothers present, consumed more spotted knapweed 11 days later than non-conditioned lambs. Conditioning lambs only in a group setting with their peers may have the greatest potential to enhance consumption of spotted knapweed, because of social facilitation and the predilection for young animals to try novel feeds.     

Body size dimorphism and sexual segregation in polygynous ungulates: an experimental test with Soay sheep

Sexual segregation in Soay sheep (Ovis aries) was investigated using an experimental approach in order to test the sexual dimorphism-body size hypothesis. Two corollaries of the sexual dimorphism-body size hypothesis were tested: (1) in dimorphic species males, the larger sex, have relatively smaller bite sizes on short swards because of the scaling of incisor arcade with body weight, and (2) they move off earlier to feed on taller but poorer-quality swards when such swards are patchily distributed on a scale which enables the spatial segregation of individuals. Patch choice between sexes was estimated using a matrix of grass patches which differed in both quality and biomass of grass on offer (HQ: high-quality-low-biomass; LQ: low-quality-high-biomass). Sex differences in patch choice and grazing behaviour were tested in short-term preference trials. Incisor breadth showed no significant difference between sexes. On the other hand, muzzle width was dimorphic, with females having a narrower muzzle than males. Bite size was significantly different between the sexes, being smaller in females than in males, although it was not significantly different between sward types. Females had a higher bite rate than males and the bite rate was higher in the HQ sward type than the LQ sward type. When the effect of body mass was removed, no sex differences in muzzle size, bite size or bite rate were found. The intake rate did not differ between the sexes or between sward types. Whilst both sexes preferred the HQ sward type, females spent a significantly longer time feeding on the LQ sward type than did males. The difference detected between the sexes in patch choice was not consistent directly with the sexual dimorphism-body size hypothesis. Alternative explanations based on sex differences in foraging behaviour in relation to body mass sexual dimorphism are discussed to explain the result. Received: 1 February 1999 / Accepted: 12 May 1999     

王朗国家级自然保护区滑坡体兰科植物分布格局及其保护策略

滑坡体是大熊猫国家公园岷山片区中广泛存在的一种生境, 但其在生物多样性研究和保护中的作用却没有得到足够的重视。王朗国家级自然保护区的滑坡体具有丰富的兰科植物资源, 其中白沙沟滑坡体最为丰富。本文以白沙沟滑坡体为例, 探究岷山地区滑坡体生境中兰科植物的空间分布格局, 拟为王朗国家级自然保护区及周边区域的兰科植物保护提供指导。本研究设置4条样带共186个样方, 利用除趋势对应分析(DCA)和双向指示种分析(TWINSPAN)研究滑坡体兰科植物的空间分布格局, 同时对兰科植物做了种间关联和相关性分析。结果表明, 白沙沟滑坡体的草本群落受环境因素的影响, 物种间竞争较弱, 处于自然演替的初始阶段。郁闭度和水流冲刷对滑坡体兰科植物的分布具有重要影响。受郁闭度和水流干扰因素的影响, 滑坡体可分成滑坡体-林缘生境(类型1)、滑坡体生境(类型2)和高郁闭度滑坡体生境(类型3) 3种类型。兰科植物在类型1和类型3两种生境中产生了适应性分化。建议在一些兰科物种集中分布的区域设立保护点并进行监测。此外还应对其他不同时间、不同土壤基质形成的滑坡体进行详细的调查, 摸清王朗国家级自然保护区甚至岷山地区兰科植物分布的整体情况。     

中国三江源国家公园与韩国智异山国家公园的对比研究

自1967年智异山被认定为韩国首个国家公园以来,韩国以国家公园为主体的自然保护地体系建设已历经50余年。这期间韩国在国家公园的建设中积累了大量经验,十分值得我国借鉴。选取我国首个国家公园体制试点——三江源国家公园和韩国首个国家公园——智异山国家公园为研究对象,对二者的管理现状进行了定性分析,并运用基于最优实践的国家公园管理能力评价方法对二者的管理能力进行了定量评价。研究表明:三江源国家公园的管理能力综合得分低于智异山国家公园,在体制建设、保障机制、资源环境管理、社区管理和科普教育五个方面均与智异山国家公园存在一定差距;智异山国家公园在资源本底调查、法制建设、多方参与、环境教育和游憩管理方面的管理能力十分突出,为三江源国家公园管理能力的提升提供了有益借鉴;三江源国家公园在生态补偿和制度约束方面具有比较优势,但在自然资源权属、资源本底调查、社区组织建设和游憩管理方面则亟待提升。在此基础上,针对三江源国家公园建设提出了强化科研支撑、健全多方参与制度、推进全民福利共享三项建议,针对我国国家公园体制建设提出了制定《国家公园法》、设置自然保护地顶层规划两项建议,以期促进三江源国家公园管理能力提升、推动我国国家公园体制建设。     

旅游废弃物生态影响评价——以九寨沟、黄山风景区为例

从旅游生态系统物质与能量循环的特点出发,提出旅游废弃物的概念,构建基于生态足迹的旅游废弃物生态影响评价模型,并以九寨沟、黄山风景区为例进行实证比较研究.研究结果表明:(1)2004年九寨沟旅游废弃物生态足迹总量为46960.5678hm2,是黄山总量22331.4490hm2的2.1倍,人均0.024560966hm2是黄山人均0.01394088 hm2的1.76倍.(2)显性生态因子的废水、粪便、固体垃圾、废弃物处理设施的生态足迹很小,4类合计仅占总量的0.16%(九寨沟)与0.3%(黄山),而隐性生态因子CO2排放的生态足迹则占总量的99.84%(九寨沟)与99.70%(黄山).(3)2004年九寨沟与黄山旅游业的CO2排放量分别高达309455.66t与146947.84t,游客人均CO2排放量分别为161.85kg、91.74kg,旅游业的CO2排放对全球气候变化与生态影响的特征明显.(4)旅游废弃物生态足迹中游客占1%,居民占0.26%,而相关企业(交通、饭店)占98.74%.(5)旅游废弃物对九寨沟风景区、成都-九寨沟沿途区域、成都—九寨沟沿途区域以外地区不同空间尺度的生态影响分别为1.26%、34.8%、63.94%;对黄山风景区、黄山市区域、黄山市区域以外地区的生态影响分别为14.6%、31.97%、53.43%.(6)2004年九寨沟、黄山旅游业的生态效率分别为2.53kgCO2-e/US$、1.67kgCO2-e/US$,生态效率值偏大,对生态环境的影响深远.(7)由于风景区规模、性质、游客构成以及游客选择交通工具的差异,旅游废弃物对不同旅游地生态影响的程度与方向不同,而降低游客规模、缩短旅行距离、减少飞机旅行方式等是降低旅游废弃物生态影响的关键.     

浙江天童国家森林公园红凉伞交配系统研究

 交配系统是影响植物种群遗传结构的重要因素之一,测定植物的交配系统不仅可以了解物种的繁殖格局,而且也有助于预测生境条件发生变化(如生境片断化)时物种遗传结构的变化趋势。红凉伞是常绿阔叶林伴生小灌木,雌雄同花。采用水平切片淀粉凝胶电泳法分析种子萌发幼苗的基因型,结合Ritland异交率估算模型(MLT),测定了浙江天童国家森林公园红凉伞的交配系统,共采用了3个酶位点(Adh-1,Fe-2和Amp-2)。两个红凉伞种群的异交率均大于1,分别为1.055和1.159,可能是由于处理过程中将小的集群合并处理的结果,因为小集群内家系数量少,无法计算异交率。计算的家系异交率大多很大,只是在小集群内存在异交率低的家系,表明当红凉伞聚生形成的集群内开花个体数少时,异交率将降低。分析了常绿阔叶林片断化对红凉伞种群交配系统的影响。     

自然旅游地居民自然保护态度的影响因素——中国九寨沟和英国新森林国家公园的比较

居民的自然保护态度对自然旅游地的自然保护与旅游可持续发展至关重要,自然旅游地居民自然保护态度的影响因子及影响方式,已经成为自然旅游地管理的重要内容,但相关研究薄弱。以中国九寨沟和英国新森林国家公园(New Forest National Park,NF)为例,根据实地问卷调查数据,从两地居民的人口属性、旅游环保期望、旅游环境影响感知及旅游环境伦理观与其自然保护态度关系的角度,进行定量比较研究。研究发现:(1)两地居民的自然保护态度受不同因子的影响,存在明显的中外差异;(2)人口属性特征如性别、年龄、居住年限、教育水平及旅游业参与情况对新森林国家公园社区居民的自然保护态度没有影响;但性别、旅游业参与情况却影响九寨沟居民的自然保护态度,女性及旅游业参与者更支持对九寨沟进行自然保护;(3)新森林国家公园居民的自然保护态度受其旅游环保期望及旅游环境伦理观的影响:旅游环保期望较高、持保护主义环境伦理观的新森林国家公园居民,更有可能支持对新森林国家公园进行自然保护;(4)九寨沟居民的自然保护态度不受其旅游环保期望及旅游环境伦理的影响,但受其旅游环境影响感知的影响;居民的旅游环境影响感知越消极,越支持对九寨沟进行自然保护。