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1.
新疆马鹿(Cervus elaphus)有3个亚种(塔里木亚种C.e.yarkandensis、天山亚种C.e.songarieus和阿勒泰亚种C.e.sibirieus)。本文报道新疆马鹿3个亚种头骨形态学特征描述和14项形态学指标测定。被测定的指标主要有颅全长(GLC)、颜面长(FL)、鼻骨全长(GLN)、前头长(MFL)、眼窝长(OFW)、基底全长(CBL)、口盖最大幅(GPB)、前臼齿间距离(Pm—P)、眼间最小幅(ZB)、筋突起高(CH)、关筋突起高(LH)、牙齿间隙裂高(DH)、前下颚骨高(HMP2)、后下颚骨高(HMM,),采用主成分分析并在这3个亚种之间进行了比较。结果表明:1)阿勒泰亚种的头骨长度和高度值比塔里木亚种大,宽度值比塔里木亚种小;2)天山亚种的头骨大小一般处在塔里木亚种和阿勒泰亚种的中间,但三者之间没有显著性差异;3)阿勒泰亚种和天山亚种的头骨形态测量数据比较接近,塔里木亚种的头骨形态比较特殊(塔里木亚种的头骨短而宽,明显区别于其他两亚种的特征)。在新疆导致马鹿3个亚种头骨形态差异的主要因素有栖息地环境和气候因素的差异。阿勒泰亚种和天山亚种栖息在大陆性气候寒冷区的针叶林中,冬天气候比较寒冷;塔里木亚种栖息在大陆性气候温热区的塔里木河流域胡杨林中,气候干旱炎热。因此,阿勒泰和天山亚种在适应寒冷的气候并适应生软食物的食性过程中头骨变成长细,而塔里木亚种长期适应干旱炎热并适应生硬食物的食性使头骨变的短而宽。 相似文献
2.
As compared to natural forests, managed boreal forests are younger, more homogeneous in terms of tree age and species composition,
and consist of smaller fragments. Here we examine the effects of such characteristics caused by forestry on carabid beetles
(Coleoptera, Carabidae) in the boreal region. The main results are the following. (1) Fragmentation of forests and the size
of a fragment appear not to be crucial for the survival of the majority of forest carabids, as they tend to be distributed
over various successional stages, but species requiring old-growth habitats suffer. (2) For carabids there appear to be no
or very few edge specialist species, and forest-open land edges appear to be effective barriers for species associated with
forest or open habitat. However, generalist species easily cross the edge, and edges of forest fragments may be invaded by
species from the surrounding open habitat. (3) Habitat change following clear-cutting dramatically changes the composition
of carabid assemblages: species restricted to mature forests disappear and open-habitat species invade, while habitat generalists
survive at least in the short term. Carabid diversity can probably best be maintained if forest management mimics natural
processes, maintains natural structures and includes the natural composition of vegetation and other structural elements (such
as dead wood) within the stands, provided that these forest features can be maintained and recreated through forest management
practices. At a larger scale, the whole spectrum of forest types and ages (especially old-growth forests), and different successional
processes (especially fire) should be maintained. These require the development and use of innovative logging methods, and
the planning, implementation, and assessment of landscape-scale ecological management strategies. 相似文献
3.
A review of the ground beetles of the Ukrainian fauna is given. Almost 750 species from 117 genera of Carabidae are known to occur in the Ukraine. Approximately 450 species of ground beetles are registered in the Carpathian region. No less than 300 species of ground beetles are found in the forest zone. Approximately 400 species of Carabidae present in the forest-steppe zone are relatively similar in species composition to those in the forest territories. Some 450 species of Carabidae are inhabitants of the steppe zone. Representatives of many other regions of heterogeneous biotopes such as forest, semi desert, intrazonal, etc. can be found in the steppe areas. The fauna of Carabidae (ca. 100 species) of the lowlands of southern Ukraine (sandy biotopes), situated mostly in the Kherson region, is very peculiar. The fauna of the Crimean mountains contains about 300 species. Conservation measures for the Carabidae are discussed. 相似文献
4.
塔里木马鹿分布在干旱地区,是唯一的适应干旱荒漠环境的特殊马鹿亚种之一.目前,塔里木马鹿种群面临着栖息地退缩和片段化的双重影响,这不仅导致了种群数量的锐减,而且也因物种遗传漂变和近亲繁殖的不断增加,进一步加剧其濒危程度.为了有效地保护该物种,全面了解种群结构是至关重要.对塔里木马鹿粪便的长度、宽度、长度/宽度比例和体积等参数进行了测量,并采用判别分析方法划分种群年龄.结果表明,塔里木马鹿粪便形态在不同性别之间有差异,一般雌性的粪便大于雄性(P<0.05).同时根据粪便形态对种群年龄划分为成年雄性、成年雌性和幼体等3个年龄组. 相似文献
5.
目的:检测雄性塔里木马鹿的睾酮,雌鹿的雌二醇、雌三醇、孕酮等粪便激素含量,并比较不同月份之间的变化。方法:利用放射免疫分析法(RIA)在且末和尉犁县马鹿场采集塔里木马鹿粪便,检测了2004年2~12月间塔里木马鹿粪便中的激素水平。结果:粪便性激素水平有明显的季节变化(P<0.05)。雄鹿粪便睾酮水平月间差异显著(P<0.05),浓度在8月有2个高峰。雌鹿粪便雌二醇在3月和6月有2个高峰;粪便孕酮水平在3月有2个高峰,在8月有1个高峰;雌三醇差异不显著,但4月的最高值也显著高于其他各时间点(P<0.05)。结论:利用动物粪便研究激素具有对保护动物完全无伤害、材料收集容易等优点,并且有助于评估动物青春期的健康状况、判断动物排卵方式、早孕检查、产前预测等,因而是目前研究野生珍稀动物性激素的一种较为理想的方法。 相似文献
6.
Abstract The impact of silvicultural practices (clearfelling, slash burning and sowing) on carabid beetle communities in tall wet Eucalyptus obliqua forests in southern Tasmania was examined using traplines of pitfalls in a chronosequence of regenerating coupes. Total species richness ( n= 18) was modest compared to other temperate forests and was not systematically changed by forest management, although it was considerably lower in 20 year old regrowth than in younger regrowth or old-growth controls, possibly due to habitat simplification. The Shannon-Weiner Index was at a minimum in intermediate aged regeneration. TWINSPAN analysis assisted recognition of beetle communities typical of broad stages in the forest succession, with a major dichotomy between most old-growth sites plus young sites and intermediate plus advanced regeneration sites. Vector fitting of environmental variables in an ordination of the sites by non-metric multidimensional scaling revealed a significant influence for the age of regeneration and litter depth, but not bare ground percentage or soil pH. Survival of carabids in the habitat mosaic created by commercial forestry activity is likely to depend on both reinvasion from edges and survival of individuals in the fire-protected refuges that exist within the coupes. Pioneer species were winged, small in size, and non-endemic whereas the opposite was true of the fauna in the older sites. Carabids in eucalypt forests have good potential as indicators but their seasonality in occurrence demands that sampling be extended over most of the year. 相似文献
7.
Bullet-derived lead in game food products is an important source of human contamination. Careless removal of tissues from around the bullet pathway in the animal body results in elevated lead doses being ingested by humans. To assess bullet-derived lead contamination of soft game tissues, muscle tissue samples were collected from ten wild boars and ten red deer immediately after they had been shot. The samples were collected from around the entry and exit wounds, from around the bullet pathway at different sites along its length, and from a distance of about 5, 15, 25, and 30 cm from the bullet track. The individuals examined differed in the lead contents in their tissues surrounding the entry and exit wounds and at different sites along the bullet pathway. One of the animals showed as much lead as 1,095.9 mg kg −1 wet weight in the tissue surrounding the bullet track near the entry wound, 736.0 mg kg −1 being recorded around the exit wound. 相似文献
8.
Few studies in wild animals have assessed changes in mineral profile in long bones and their implications for mechanical properties. We examined the effect of two diets differing in mineral content on the composition and mechanical properties of femora from two groups each with 13 free-ranging red deer hinds. Contents of Ca, P, Mg, K, Na, S, Cu, Fe, Mn, Se, Zn, B and Sr, Young’s modulus of elasticity ( E), bending strength and work of fracture were assessed in the proximal part of the diaphysis (PD) and the mid-diaphysis (MD). Whole body measures were also recorded on the hinds. Compared to animals on control diets, those on supplemented diets increased live weight by 6.5 kg and their kidney fat index (KFI), but not carcass weight, body or organ size, femur size or cortical thickness. Supplemental feeding increased Mn content of bone by 23%, Cu by 9% and Zn by 6%. These differences showed a mean fourfold greater content of these minerals in supplemental diet, whereas femora did not reflect a 5.4 times greater content of major minerals (Na and P) in the diet. Lower content of B and Sr in supplemented diet also reduced femur B by 14% and Sr by 5%. There was a subtle effect of diet only on E and none on other mechanical properties. Thus, greater availability of microminerals but not major minerals in the diet is reflected in bone composition even before marked body effects, bone macro-structure or its mechanical properties are affected. 相似文献
9.
Factors affecting the light response of the riparian species Bembidion petrosum (Coleoptera: Carabidae) were studied with various experimental designs in laboratory and in field. B. petrosum, which lives in open gravely/stony sites, oriented towards directed light at higher temperatures (above 15.0°C). This positive phototaxis was replaced by an orientation towards a dark silhouette (screen) at low temperatures. The orientation towards silhouettes is mainly a simple type of form vision, although a fraction of the individuals seems to exhibit a negative phototaxis. In experiments with a dark zone and a zone with directed light, individuals of B. petrosum mainly selected the dark zone. However, if two stones were placed in the light part of the arena, individuals tended to hide under them. This applied independent of light intensity and whether a tuft of grass was present or absent in the dark part of the arena. The experiments indicate that the shift of the species between the reproduction (spring/summer) and hibernation (autumn/winter) habitat involves a change from an orientation towards silhouettes at low temperatures in autumn to an orientation towards directed light at higher temperatures in spring. This is combined with a specialized low thigmokinesis (preference of heavy and rough objects) and lower moisture requirements of the species in autumn/winter than in spring/summer. 相似文献
10.
Labial and maxillary palps in 22 species of ground beetle larvae revealed the presence of four different types of sensilla: sensilla digitiformia, sensilla campaniformia, sensilla basiconica and sensilla chaetica. Using transmission electron microscopy techniques, the role of most of them was defined: sensilla campaniformia and sensilla chaetica are mechanoreceptors; while sensilla basiconica are chemoreceptors. Sensilla digitiformia can be both mechanoreceptors and chemoreceptors, though hygroreception may also be postulated on the basis of their abundance on the mouthparts of some hygrophilous species that depend on damp or wet patchy biotopes/seasons. The number and location of the sensory structures has been found to vary among the investigated taxa. The differences are related to the larval behavioural types, and are an adaptive response to different lifestyles, feeding habits and use of space. 相似文献
11.
Carabus nitens, one of the most endangered ground beetles in Central Europe, was investigated with pitfall traps at 30 sampling sites in 17 heath fragments of the largest German heath landscape under nature conservation (nature reserve 'Lüneburger Heide'). The preference for damp Erica heaths and dry Calluna heaths in the building phase was thereby evident. Calluna heaths in the mature and degenerate phase, with and without extensive coverage by Avenella flexuosa, are either not inhabited or are avoided. The results of ovary dissections indicate that the populations in two successive spring seasons consisted mainly of animals which had already reproduced and were therefore older than one and a half years. Allozyme electrophoreses revealed variation for three of the nine investigated enzyme loci, and large differences in the allele frequency at one of these loci indicated genetic drift and fluctuations in the size of local populations. According to these results and statements in the literature, the loss of heathland areas and habitat quality are both responsible for the decline of the species. Suitable measures for preserving the species are (1) restoration of building phases of the Calluna heaths and (2) interconnection of at least the smaller heath fragments. Finally, recommendations are given for reintroductions. 相似文献
12.
External and internal thoracic structures of two carabid species (Trechini) were examined and documented with different techniques. The study has a main focus on the eyeless cave-dwelling specialist Sinaphaenops wangorum, but detailed information is also provided for a species occurring in cave entrances. The phylogenetic background of the structural features of the thoracic skeletomuscular system was addressed. The thoracic morphology of the examined species was compared to conditions observed in previously studied carabids and non-related subterranean leiodids (Staphylinoidea) in order to identify cave adaptations. Main thoracic character complexes linked with cavernicolous habits in Trechini are elongation of the pro- and mesothorax and the legs, and a complete and irreversible reduction of the flight apparatus. The lost flight capacity is linked with a far reaching modification of skeletal elements of the metathorax including a strongly shortened and simplified metanotum, a shortened metaventrite, and completely reduced wings and sclerites of the wing base. The elongate prothorax together with the long and slender head and elongated legs distinctly increases the activity range in the subterranean lightless environment, which likely facilitates foraging of the carnivorous beetles. Some of the observed features like wing loss and elongation of the anterior thorax and legs are also found in some cave-dwelling Leiodidae (Leptodirini), whereas some other subterranean members of the staphylinoid family have a compact body and legs of normal length. In contrast to the predaceous Trechini, Leptodirini are scavengers. 相似文献
13.
Laboulbenia ophioneae is described as a new species with illustrations. It is closely related to Laboulbenia celestialis and Laboulbenia asiatica because of some similarities in the morphology of appendages and perithecia. The present species from the latter two species
can be distinguished by the shorter, inflated perithecia, the shorter receptacles, and the appendages consisting of more or
less darkly colored, broader branches. This new species was found on elytra of Ophionea indica from Taiwan, which has been also known as a host of Laboulbenia polymorpha. A mature thallus noticed by Terada (2004) on the slide 673b (M. Ishikawa collection) and a young thallus illustrated by
Sugiyama (1978, fig. 1-G as L. polymorpha) on 673d (M. Ishikawa collection) are both identified as L. ophioneae. 相似文献
14.
Degraded areas constitute challenging tasks with respect to sustainable management of natural resources. Maintaining or even establishing certain successional stages seems to be particularly important. This paper presents a model of the succession in five different types of degraded areas in Poland based on changes in the carabid fauna. Mean Individual Biomass of Carabidae (MIB) was used as a numerical measure for the stage of succession. The run of succession differed clearly among the different types of degraded areas. Initial conditions (origin of soil and origin of vegetation) and landscape related aspects seem to be important with respect to these differences. As characteristic phases, a 'delay phase', an 'increase phase' and a 'stagnation phase' were identified. In general, the runs of succession could be described by four different parameters: (1) 'Initial degradation level', (2) 'delay', (3) 'increase rate' and (4) 'recovery level'. Applying the analytic solution of the logistic equation, characteristic values for the parameters were identified for each of the five area types. The model is of practical use, because it provides a possibility to compare the values of the parameters elaborated in different areas, to give hints for intervention and to provide prognoses about future succession in the areas. Furthermore, it is possible to transfer the model to other indicators of succession. 相似文献
15.
Low reproductive productivity of young red deer ( Cervus elaphus) hinds on New Zealand deer farms appears to reflect high incidences of puberty failure at 16 months of age. This is despite the general attainment of average liveweights 15–25 kg in excess of the accepted minimum threshold for puberty in subspecies of western European origin ( scoticus, elaphus and hippelaphus) that form the basis of the national herd. The present study tests the hypotheses that introgression of the larger North American wapiti subspecies ( nelsoni, manitobensis and roosevelti) into breeding herds (1) can be assessed from morphological features of individuals, (2) that there is a relationship between the level of wapiti parentage and non-pregnancy rate at 18 months of age (a proxy for puberty failure) and (3) that minimum liveweight thresholds for puberty increase with increasing levels of wapiti parentage. A total of 4329 18-month-old hinds across four “red” deer farms in southern New Zealand were scanned for pregnancy status. Each hind was assigned a wapiti score (WS) as a subjective assessment of the obviousness of wapiti features. Various body measurements were additionally recorded for each hind. A hair sample was collected for DNA analysis (14 markers) to objectively assign subspecies pedigree (i.e. “Elkmeter”) on a subset of 1258 individuals. A total of 506 (11.7%) hinds were not pregnant at 18 months of age with rates varying between 4.1 and 37.3% between farms and years. Mean WS differed significantly between farms and reflected the genetic management policy of each farm. WS was positively correlated to Elkmeter for each farm/year (<0.05) although regression slopes varied significantly. WS was able to be adjusted for these differences to assign a corrected WS (CWS) for all 4329 individuals that estimated the proportion wapiti parentage. Discriminant analysis of morphological variables relative to Elkmeter supported the first hypothesis and showed that shoulder height and body length were good indicators of the degree of wapiti parentage within individuals. This enabled the development of an objective estimate of wapiti parentage (EWP). The actual level of such parentage within herds ranged from <5 to >55%. There was a significant negative association between wapiti parentage and pregnancy, which was strongly influenced by liveweight, supporting the second and third hypotheses. This was manifest as marked displacement of pregnancy probability curves in relation to liveweight between genotype groups, particularly for those groups with >20% wapiti parentage. For example, predicted threshold liveweights required to achieve a 90% pregnancy rate for EWP values that represent 0, 10, 20, 30, 40 and 50% wapiti parentage were 81, 81, 85, 106, 127 and 137 kg, respectively. Within the study herds, the majority of hinds of 0–20% wapiti parentage exceeded the predicted 90% threshold liveweights for their genotype cohort. However, hinds with higher levels of wapiti parentage generally fell below the predicted threshold for their genotype group. The data strongly suggest that under liveweight performance levels measured for red deer, hinds with >20% wapiti parentage are at high risk of puberty failure. 相似文献
16.
Although most Carabidae are recognized as predacious, recent studies have shown that some tropical rain forest Carabidae use the small seeds of fallen fruit from some tree species as a key food resource (particularly figs [Moraceae] but also those from other families). Assemblages of carabid beetles (Coleoptera: Carabidae) at fruit falls of the Melastomataceae tree genera, Bellucia, Loreya, and Miconia, were studied in a terra firme rain forest near Manaus (Amazonia, Brazil) from February 1992 to August 1996. Of 5483 specimens of 14 carabid species collected at 53 fruit falls, 98.2 percent of the collected beetles represented the seed-feeding genus Notiobia. Four of the 7 Notiobia species were found to reproduce at Melastomataceae fruit falls. The most abundant species, N. glabrata, was found to be a Melastomataceae seed generalise while N. maxima seemed to prefer the seeds of Bellucia, and N. aulica and Af. umbrifera the seeds of Miconia. The presence of larvae indicated reproduction of N. glabrata at fruit falls of all three tree genera and reproduction of N. maxima at those of Bellucia. Fruit falls of different species and genera of Melastomataceae appeared to occur at different times of die year and not continuously throughout the year. The seed-feeding Notiobia species, which specialize on Melastomataceae, used fruit falls of figs as migratory “stepping stones” during periods when there were no Melastomataceae fruit falls. The comparable suite of fig seed-feeding specialist species of Notiobia did not appear to do the reverse and seemed to avoid Melastomataceae fruit falls. The carabid assemblage at fig fruit falls was more diverse than the assemblage at those of Melastomataceae. Among the Melastomataceae, carabid species richness was highest at Miconia fruit falls and lowest at Loreya fruit falls. The three most common predatory species caught at Ficus fruit falls were also caught at those of Melastomataceae and appeared to reproduce at both fruit fall types. The proportion of the carabid assemblage accounted by predatory species was much lower at Melastomataceae (1.8%) than at fig fruit falls (8%). 相似文献
17.
Increased interest in biomass harvesting for bioenergetic applications has raised questions regarding the potential ecological consequences on forest biodiversity. Here we evaluate the initial changes in the abundance, species richness and community composition of rove ( Staphylinidae) and ground beetles ( Carabidae), immediately following 1) stem-only harvesting (SOH), in which logging debris (i.e., tree tops and branches) are retained on site, and 2) whole-tree harvesting (WTH), in which stems, tops and branches are removed in mature balsam fir stands in Quebec, Canada. Beetles were collected throughout the summer of 2011, one year following harvesting, using pitfall traps. Overall catch rates were greater in uncut forest (Control) than either stem-only or whole-tree harvested sites. Catch rates in WTH were greater than SOH sites. Uncut stands were characterized primarily by five species: Atheta capsularis, Atheta klagesi, Atheta strigosula, Tachinus fumipennis/ frigidus complex ( Staphylinidae) and to a lesser extent to Pterostichus punctatissimus( Carabidae). Increased catch rates in WTH sites, where post-harvest biomass was less, were attributable to increased catches of rove beetles Pseudopsis subulata, Quedius labradorensis and to a lesser extent Gabrius brevipennis. We were able to characterize differences in beetle assemblages between harvested and non-harvested plots as well as differences between whole tree (WTH) and stem only (SOH) harvested sites where logging residues had been removed or left following harvest. However, the overall assemblage response was largely a recapitulation of the responses of several abundant species. 相似文献
18.
The Corsican red deer, a sub-species of the European red deer endemic to Sardinia and Corsica, was abundant on both islands
at the beginning of 1900. It went extinct in Corsica and reached a minimum of 100 individuals in Sardinia by 1970. Numbers
have recovered in Sardinia with more than 1,000 rutting males now present; in the 1980s the deer was reintroduced to Corsica,
but the Sardinian population remains fragmented. We developed a potential distribution model in Sardinia using Ecological
Niche Factor Analysis. To assess the deer’s protection status we compared the model with the existing and proposed conservation
areas and investigated different conservation scenarios in relation to the expansion of its current range and resilience to
future changes in land use and predicted trends of desertification. According to our results over 70% of Sardinia is unsuitable
to the deer, nevertheless high suitability areas (Mediterranean forests away from main roads) are available throughout the
island, particularly in the south and in the central-eastern part. Existing protected areas do not provide for the conservation
of the deer but public owned forests, where hunting is prohibited, extend some level of protection, and the protected areas
proposed by the Regional administration, if implemented, will be increasing this protection. Three main areas have emerged
as conservation priorities to guarantee adequate conservation potential in the future. Our approach provides valuable data
to inform conservation policy, and could be easily replicated in other parts of the Mediterranean. 相似文献
19.
Comparisons of structural features (principally mouthparts, elytral-abdominal locking mechanism, and female genitalia) of the ardistomine genera (Aspidoglossa Putzeys, Ardistomis Putzeys, and Semiardistomis Kult) with those features of members of the subtribe Clivinina (Clivina Latreille, Oxydrepanus Putzeys, Schizogenius Putzeys,Ancus Putzeys, Nyctosyles Putzeys, and Obadius Burmeister) confirm the taxonomic validity of the subtribe Ardistomina. Based on morphological features, the ardistomine genera are postulated to be related as follows: [Aspidoglossa [Ardistomis + Semiardistomis]]. Knowledge of this subtribe is further extended by taxonomic treatment of the genus Semiardistomis Kult. Of the 30 valid names of Semiardistomis previously recognized, four were proposed as variety names, and are listed as junior synonyms: Ardistomis labialis picipes Bates, 1881, Ardistomis labialis nanus Bates, 1881, and Ardistomis labialis dilatatus Bates, 1881; and Ardistomis pallipes caerulea Putzeys, 1846. Eight names, treated as specific epithets, are junior synonyms, as follows: Ardistomis (Semiardistomis) balthasari Kult, 1950 = Semiardistomis glabratus (Putzeys, 1866); Ardistomis (Semiardistomis) emdeni Kult, 1950 = Semiardistomis deletus (Putzeys, 1846); Ardistomis aenea Putzeys, 1866, Ardistomis (Semiardistomis) brittoni Kult, 1950, and Ardistomis (Semiardistomis) marani Kult, 1950 = Semiardistomis flavipes (Dejean, 1831); Ardistomis tuspanensis Putzeys, 1846 = Semiardistomis labialis (Chaudoir, 1837); Ardistomis (Semiardistomis) vlastae Kult, 1950 = Semiardistomis subglabra (van Emden, 1949); and Ardistomis striga Putzeys, 1866 = Semiardistomis pallipes (Dejean, 1831). Two new species described are Semiardistomis exspectatussp. n.(type locality PERU, Madre de Dios, Rio Manu, 11°56'47"S, 071°17'00"W), and Semiardistomis majorsp. n. (type locality PERU, Loreto, Rio Samiria, 05°12'S, 75°20'W). The 20 species of Semiardistomis are arranged intwo species-groups here proposed: the puncticollis group, including 12 species; and labialis group, including eight species. The species recognized are keyed, described or redescribed, and notes are provided about their Geographical distribution, habitat and activity. Distribution maps show known geographical ranges, from which are inferred patterns of speciation from a center of radiation in northern South America of both lineages. 相似文献
20.
1. In addition to exhibiting preferences for particular plant species, vertebrate herbivores select particular individuals of these species whilst leaving others undamaged. This pattern of diet selection may reflect differences in the chemical composition (and hence nutritional quality) between individual plants, and/or variability in the physical constraints on intake rate, such as plant structure. 2. An experiment was conducted to test the effects of environmental manipulations on the morphology and chemical composition of Sitka Spruce saplings, and to evaluate the consequences for herbivory by Red Deer. Fertilizing the trees increased tree height, branch span and leader length, twig width and needle width, and decreased the concentrations of total phenolics, condensed tannins, fibre and lignin but monoterpene content was not altered. Shading also reduced phenolic and tannin concentrations. 3. When the fertilized and shaded trees were offered to deer in feeding trials, the probability of a tree being visited by a deer and the biomass removed were influenced by tree morphological variables, as were the bite rate and intake rate of the deer. More biomass was removed from larger trees. 4. Once the effects of tree morphology had been taken into account, there was no effect of the fertilizer and shade treatments on deer browsing behaviour that could be attributed to changes in chemical composition of the trees. The relationship between intake rate and bite size at each tree varied between individual deer, but the functional response relationship between intake rate and bite size was not influenced by the treatments applied to the trees. 5. Tree morphology may have a larger influence on deer feeding behaviour than tree chemical composition. 相似文献
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