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1.
Biomechanical models of the gecko adhesive system typically focus on setal mechanics from a single gecko species, Gekko gecko. In this study, we compared the predictions from three mathematical models with experimental observations considering an additional gecko species Phelsuma grandis, to quantify interspecific variation in setal micromechanics. We also considered the accuracy of our three focal models: the frictional adhesion model, work of detachment model, and the effective modulus model. Lastly, we report a novel approach to quantify the angle of toe detachment using the Weibull distribution. Our results suggested the coupling of frictional and adhesive forces in isolated setal arrays, first observed in G. gecko is also present in P. grandis although P. grandis displayed a higher toe detachment angle, suggesting they produce more adhesion relative to friction than G. gecko. We also found the angle of toe detachment accurately predicts a species’ maximum performance limit when fit to a Weibull distribution. When considering the energy stored during setal attachment, we observed less work to remove P. grandis arrays when compared with G. gecko, suggesting P. grandis arrays may store less energy during attachment, a conclusion supported by our model estimates of stored elastic energy. Our predictions of the effective elastic modulus model suggested P. grandis arrays to have a lower modulus, E eff, but our experimental assays did not show differences in moduli between the species. The considered mathematical models successfully estimated most of our experimentally measured performance values, validating our three focal models as template models of gecko adhesion (see Full and Koditschek in J Exp Biol 202(23):3325–3332, 1999), and suggesting common setal mechanics for our focal species and possibly for all fibular adhesives. Future anchored models, built upon the above templates, may more accurately predict performance by incorporating additional parameters, such as variation in setal length and diameter. Variation in adhesive performance may affect gecko locomotion and as a result, future ecological observations will help to determine how species with different performance capabilities use their habitat.  相似文献   

2.
Many invasive alien plants drive changes in native community composition, structure and diversity. They alter soil nutrient regimes of native communities and affect native plant recovery outcomes following their removal. We assessed whether Eucalyptus grandis invasion and removal alters the soil physico‐chemical properties and native vegetation recovery in the Eastern Cape Province, South Africa. We collected samples from topsoil in E. grandis invaded sites (canopy cover > 75%), cleared sites (eight years ago) and native sites (canopy cover > 80%) and quantified soil moisture, concentrations of soil macro elements (N, C and P), pH and exchangeable cations (K, Ca, Mg, Na) as well as measured soil water repellency using the Water Droplet Penetration Time and infiltration. We conducted vegetation surveys in plots measuring 10 × 10 m. Invasion by E. grandis had varying effects on soil physico‐chemical properties, causing increase in soil pH and P, while decreasing total N and C. The removal of E. grandis also showed varying effects on soil physico‐chemical properties, but seems to have further triggered the loss of some soil nutrients (especially soil P). Soil water repellency (a measure of soil compaction) has improved in cleared sites to non‐repellent soils compared to repellent soils in invaded site. Eucalyptus grandis reduced species richness of the invaded sites. The presence of native species on cleared sites indicates a positive trajectory towards vegetation recovery. We conclude that E. grandis invasion and removal trigger varying effects on soil properties (both increases and decreases). For soil and vegetation restoration of cleared sites to be effective, active restoration techniques such as soil transfer, nutrient manipulation and native plant seeding should be considered.  相似文献   

3.
The invasion of the giant Madagascar day gecko Phelsuma grandis has increased the threats to the four endemic Mauritian day geckos (Phelsuma spp.) that have survived on mainland Mauritius. We had two main aims: (i) to predict the spatial distribution and overlap of P. grandis and the endemic geckos at a landscape level; and (ii) to investigate the effects of P. grandis on the abundance and risks of extinction of the endemic geckos at a local scale. An ensemble forecasting approach was used to predict the spatial distribution and overlap of P. grandis and the endemic geckos. We used hierarchical binomial mixture models and repeated visual estimate surveys to calculate the abundance of the endemic geckos in sites with and without P. grandis. The predicted range of each species varied from 85 km2 to 376 km2. Sixty percent of the predicted range of P. grandis overlapped with the combined predicted ranges of the four endemic geckos; 15% of the combined predicted ranges of the four endemic geckos overlapped with P. grandis. Levin''s niche breadth varied from 0.140 to 0.652 between P. grandis and the four endemic geckos. The abundance of endemic geckos was 89% lower in sites with P. grandis compared to sites without P. grandis, and the endemic geckos had been extirpated at four of ten sites we surveyed with P. grandis. Species Distribution Modelling, together with the breadth metrics, predicted that P. grandis can partly share the equivalent niche with endemic species and survive in a range of environmental conditions. We provide strong evidence that smaller endemic geckos are unlikely to survive in sympatry with P. grandis. This is a cause of concern in both Mauritius and other countries with endemic species of Phelsuma.  相似文献   

4.
We evaluated growth responses to gap formation for juvenile individuals of three canopy rain forest species: Peltogyne cf. heterophylla, Clarisia racemosa and Cedrelinga catenaeformis. Gaps were formed during selective logging operations 7 yr before sampling in a Bolivian rain forest. We collected wood samples for tree‐ring analyses at different distances to the stump (<10, 10–40 and >40 m) and from trees with different diameters (5–30 cm diameter at breast height [dbh]). Tree‐rings width was measured in at least two radii and converted to average diameter growth. Changes in 7‐yr median diameter growth before and after selective logging were analyzed. Diameter growth rates significantly increased by 0.7–0.8 mm/yr after gap formation for P. heterophylla and C. catenaeformis, but not for C. racemosa. We applied a multiple regression analysis to explain variation in growth responses of P. heterophylla and C. catenaeformis by distance to logging gap and tree size. For P. heterophylla we found that growth increase occurring close to logging gaps was strongest for large juvenile trees (20–25 cm dbh) and almost absent in small juveniles. For C. catenaeformis, variation in growth responses was not related to tree size or distance to gaps. Our results show that growth responses to gap formation strongly differ across species and tree sizes. This finding calls for caution in the interpretation of growth releases in tree‐ring series, as gap formation does not necessarily invoke growth responses and if such growth responses occur, their strength is species‐ and size specific.  相似文献   

5.
首次报道老挝泽泻科(Alismataceae)一新记录属——泽薹草属(Caldesia),及新记录种——宽叶泽薹草(Caldesia grandis)。宽叶泽薹草为旧世界广布属泽薹草属中唯一叶宽大于叶长的物种,原记载分布在中国、孟加拉国、印度和马来西亚。同时,还提供了宽叶泽薹草的描述和其原生境图片。  相似文献   

6.
Small, benthic, cryptic fishes represent a species-rich guild on marine substrates. Most of them are micropredators that feed on crustaceans that are often smaller than 1 mm. Typical examples are seahorses and pipefishes (Syngnathidae), most gobies (Gobiidae), dragonets (Callionymidae) and triplefins (Tripterygiidae). Previous work on the yellow black-headed triplefin Tripterygion delaisi demonstrated that it actively redirects downwelling sunlight sideways using its iris and can use this to locally illuminate objects of interest. We call this form of active sensing using light “diurnal active photolocation”. Visual modelling predicted that light redirection can be sufficient to induce a perceivable change in luminance in the eyes of one of its prey species, a cryptic gammarid crustacean (Cheirocratus sp.), over distances of 1–2 cm. Empirical validation, however, was not possible because measurements of predation distances have not been quantified for free-ranging, small, benthic fishes before. Here, we present interaction distances measured from videos of T. delaisi approaching and striking at prey in the field. Out of 160 recordings, we were able to quantify 78 prey approaching distances and 100 striking distances. Approaching distances ranged from 2.1 to 4.1 cm (interquartile range, IQR) and involved one to five approaching steps before the actual strike occurred. The distance over which the final strike took place varied from 0.7 to 1.6 cm (IQR). Both approaching and striking distances increased with fish body size. We conclude that most approaching sequences started too far away to be explained by prey detection through light redirection. Striking distances, however, fell well with the distances predicted by the model. We conclude that if diurnal active photolocation plays a role in prey detection, it is during the final decision whether to strike or not.  相似文献   

7.
Toucans (Ramphastidae) are highly frugivorous, widespread throughout the Neotropics, and travel long distances, thus likely providing dispersal for many tropical trees. Despite being large conspicuous members of the canopy and subcanopy bird community, their movement ecology has been little studied. To understand how these frugivores move through a lowland tropical forest, I tracked the movements of Ramphastos tucanus (White‐throated Toucan), Ramphastos vitellinus (Channel‐billed Toucan), and Pteroglossus pluricinctus (Many‐banded Araçari) in Yasuní National Park, Ecuador. The objectives of this study were to use radiotelemetry to estimate toucan home ranges, movement patterns, and potential seed dispersal distances. Using canopy nets, a total of 20 P. pluricinctus and three Ramphastos toucans were captured, radio‐tagged, and tracked over a 4‐yr period from 2001 to 2005. Average home range sizes were 191 and 86 ha for P. pluricinctus and Ramphastos toucans, respectively. The maximum travel distance in a single 30‐min tracking interval was 3665 m for P. pluricinctus and 3027 m for Ramphastos. Estimated dispersal distances of medium‐sized seeds ranged from 269 to 449 m. Large home range size and long‐distance movements indicate that toucans likely disperse seeds over a scale of hundreds of meters. This study is the first to estimate home range size of any toucan species in intact closed‐canopy forests. Abstract in Spanish is available at http://www.blackwell‐synergy.com/loi/btp .  相似文献   

8.
There are few effective or efficient established methods for monitoring cryptic herpetofauna. Footprint tracking tunnels are routinely used to index small mammal populations, but also have potential for monitoring herpetofauna. We evaluated the utility of tracking tunnels for identification of New Zealand lizards using captive- and wild-sourced animals (four skink and eight gecko species). All skink prints that we obtained were indistinct or obscure, but we obtained relatively clear, measurable prints for all gecko species. We found that identification to species level was possible for the two gecko species for which we had a large sample—Naultinus gemmeus and Woodworthia ‘Otago large’—using linear discriminant analysis (the best model correctly assigned 96.1% of individuals). Our findings suggest that footprints from tracking tunnels may be used to distinguish between species of geckos. Additional research is needed to assess the ability to further discriminate intra- and inter-genera lizard footprints from tracking tunnels, and the utility of the technique for surveying and monitoring lizard populations.  相似文献   

9.
Questions: Do spatial and temporal patterns of encroachment of Pinus contorta and Abies grandis in a montane meadow suggest strong biotic controls on the invasion process? Location: Forest–meadow mosaic, 1350 m a.s.l., Cascade Range, Oregon, US. Methods: We combined spatial point pattern analysis, population age structures, and a time‐series of stem maps to quantify spatial and temporal patterns of conifer invasion over a 200‐yr period in three plots totaling 4 ha. Results: Trees established during two broad, but distinct periods (late 1800s, then at much greater density in the mid‐1900s). Recent invasion was not correlated with climatic variation. Abies grandis dominated both periods; P. contorta established at lower density, peaking before A. grandis. Spatially, older (≥90 yr) P. contorta were randomly distributed, but older A. grandis were strongly clumped (0.2‐20 m). Younger (<90 yr) stems were positively associated at small distances (both within and between species), but were spatially displaced from older A. grandis, suggesting a temporal shift from facilitation to competition. Establishment during the 1800s resulted in widely scattered P. contorta and clumps of A. grandis that placed most areas of meadow close to seed sources permitting more rapid invasion during the mid‐1900s. Rapid conversion to forest occurred via colonization of larger meadow openings – first by shade‐intolerant P. contorta, then by shade‐tolerant A. grandis– and by direct infilling of smaller openings by A. grandis. Conclusions: In combination, spatial and temporal patterns of establishment suggest an invasion process shaped by biotic interactions, with facilitation promoting expansion of trees into meadows and competition influencing subsequent forest development. Once invasion is initiated, tree species with different life histories and functional traits can interact synergistically to promote rapid conversion of meadow to forest under a broad range of climatic conditions.  相似文献   

10.
It has long been argued that seed dispersal enhances recruitment in tropical trees by allowing offspring to `escape' strong density/distance-dependent attack by insects, pathogens and rodents. Here we examined the effects of canopy openness and parent-offspring distance upon the frequency and timing of Chlorocardium rodiei seed attack and germination within a 15-ha plot of Guyanan tropical rain forest. Seeds were artificially dispersed beneath parent trees, in the understorey away from trees and in gaps. Analysing our data from an 85-week period of regular monitoring, we found that the main spatial gradients, canopy openness and distance to nearest adult conspecific, do not lead to differences in the final number of seeds attacked by infesting scolytid beetles or rodents. The timing of beetle attack, however, varied along the distance gradient and this difference affords seeds at further distances a `window' in which to germinate and produce a seedling before attack. Canopy openness was not a good predictor of rooting success, but distance was strongly associated with root and shoot formation success and the mean time to shoot formation. There was a strong negative effect of distance on the likelihood of a seed being colonised by scolytid beetles prior to removal by rodents and shoot failure was strongly associated with prior infestation. We believe these results bring a key point to bear on the well-established notion of distance-dependent attack on seeds in tropical rainforests, viz. that seed characteristics (size, germination syndrome) and the timing of attack may be more important in explaining patterns of early seedling recruitment than distance. Our studies suggest that advantages accrued through dispersal in species like Chlorocardium will depend heavily on the `race' between seed germination and attack. In the case of Chlorocardium, the `race' can be lost at considerable distances due to its prolonged dormancy and the temporal fluctuations in fruitfall and rainfall which influence attack and germination. The results presented here suggest that the lag between seed attack and germination in tropical trees can regulate the influence of parent-offspring distance on cohort recruitment at this life history stage. Received: 5 March 1998 / Accepted: 6 December 1998  相似文献   

11.
The vertical distribution, microenvironmental preference, canopy cover, as well as monthly fluctuations of recently described species of three genera of macropyline oribatid mites, Mesoplophora, Bicyrthermannia and Nothrus and three genera of brachypyline mites, Scheloribates, Muliercula and Galumnella were investigated over a 9-month period in shaded and unshaded areas of a secondary regrowth forest floor in Ile Ife, Nigeria. Sampling was done monthly from August 2002 to April 2003 covering the two seasons of the annual cycle. There was an overwhelming predominance of mite populations in the 5 cm topsoil compared with the fermentation and litter layers. The preference of M. ifeana and B. nigeriana extracted from the topsoil for the shaded plot was attributed to highly conducive moisture conditions provided by the canopy. It is suggested that M. ifeana, B. nigeriana, N. lasebikani, S. mochlosimilaris, M. inexpectata and G. sonpona, that exhibited a single peak density in the wet season in this study, had similar ecological needs. The populations of M. ifeana and S. mochlosimilaris were relatively stable in the fermentation layer. The study concluded that canopy cover affected the sensitivity of soil dwelling mites on the floor of a secondary regrowth forest with regard to vertical gradients of light, microclimate and foliage quality in a complex way.  相似文献   

12.
为了解桉树人工林土壤种子库特征,对不同林龄尾巨桉(Eucalyptusurophylla×E.grandis)人工林种子库的储量、垂直分布特征及与林下植被的相似度进行了分析。结果表明,土壤活力种子储量最高的为1~2 a生桉林,显著高于其他林型;其次为3~4 a生桉林和马尾松(Pinus massoniana)林;最低的为杉木(Cunninghamia lanceolata)林,显著低于其他林型。随林龄增加,尾巨桉林土壤种子库储量快速下降。土壤种子库中植物种类最为丰富的是杂木林和马尾松林,显著大于其他林型。随林龄增加,尾巨桉林土壤种子库植物种类先增后降。所有林型中,0~5 cm土壤种子库的密度均显著高于5~10 cm土层。杂木林种子库和林下植被共存植物种类最多,其次是马尾松林,杉木林最少。尾巨桉人工林随林龄的增加,共存植物种数呈先升高后下降趋势,土壤种子库Jaccard (CJ)和Sorensens (CS)相似系数也呈先升后降的趋势。因此,在速生桉人工林经营中适当间种(保留)乡土树种,可增加森林生态系统的生物多样性和生态功能的稳定性。  相似文献   

13.
In our study, we assessed patterns of resource use in an assemblage of birds by observing their foraging behaviour from a crane in the canopy of a temperate alluvial forest. We selected 12 bird species and addressed seasonal changes in feeding activity during a 2-month period in spring focussing on average staying time and utilisation of crown strata in two tree species, the common oak (Quercus robur) and the sycamore maple (Acer pseudoplatanus). We further examined ecological characteristics of the trees (i. e., crown density) that are likely to influence resource use in birds. The selected birds differed in their preference for the tree species. Most birds preferred common oaks. This preference was probably associated with higher food abundance related to substrate characteristics (i.e., roughness of bark) which offer more microhabitats for arthropods and thus permit higher densities of potential prey. Some bird species switched feeding preferences within the study period from sycamore maples to common oaks in association with tree phenology. We found two main foraging techniques. All birds searched for prey at short distance (≤50 cm) and gleaned food from substrate except the Pied Flycatcher that foraged by hovering and searched over longer distances (>50 cm). Overall, we demonstrate in our study that canopy access with mobile crane systems provides excellent opportunities to observe canopy birds and enables detailed analysis of their foraging behaviour. The main result of our study reveals fine-grained resource partitioning of birds within the canopy as an important factor structuring assemblages, with species-specific and in part also seasonal differences in stratification and substrate use.  相似文献   

14.
王馨慧  刘楠  任海  徐贝贝  简曙光 《广西植物》2017,37(1):1489-1497
对收集于广西桂林的17份野生毛葡萄种质和24份栽培葡萄种质,分别使用12条ISSR和12条SCoT引物进行了遗传多样性和亲缘关系检测。结果表明:两种分子标记均能产生较丰富的多态性片段,可有效应用于葡萄的遗传多样性检测,但在聚类分析结果上表现出一定的差异性,SCoT分子标记能更好地区分野生种质和栽培品种,说明SCoT分子标记在葡萄遗传多样性检测和系统进化研究上可能更有优势。从SCoT聚类结果上看,广西植物研究所收集的3个野生毛葡萄种质zws1、zws2和zws3相对其它野生种质而言,更偏向于与栽培种质聚为一类,说明这一类野生毛葡萄可能是这些栽培品种的原始亲本来源之一。不同的野生种质聚为多个类群,并表现出明显的地域特性,但遗传距离相对较远,说明桂林野生毛葡萄资源具有丰富的遗传变异。栽培品种没有明显的聚类特点,可能因为所选用的栽培品种的地域代表性并不是很强,也可能是因为栽培品种在不断的人工杂交选育过程中,遗传背景趋向一致,遗传多样性降低。该研究证明SCoT分子标记在葡萄遗传多样性研究上具有一定的优势。该研究结果为桂林毛葡萄资源的保护、利用和品种选育提供了理论依据,也为葡萄的系统进化研究提供了参考。  相似文献   

15.
16.
 Within the context of the reciprocal recurrent selection scheme developed in 1989 by CIRAD-Forêt on Eucalyptus, RAPD essays were performed to assess the genetic diversity in the two species E. urophylla and E. grandis. The molecular markers were split into two parts: the specific markers (present with different frequencies in the two species) and the common markers (present with similar frequencies in the two species). The study analyses the structure of genetic diversity within and between the two species of Eucalyptus. Different genetic distances are worked out for use in prediction equations of the individual tree trunk volume of hybrids at 38 months. Each distance is expressed as the sum of the general genetic distance and the specific genetic distance. The general genetic distance based on the double presence plus the double absence of bands seems to be an interesting co-variate to use in a factor regression model. Through this model the distance calculated between species explains the general combining ability (GCA) and the specific combining ability (SCA) of the phenotypic character with a global coefficient of determination of 81.6%. Received: 3 November 1996/Accepted: 8 November 1996  相似文献   

17.
In a series of studies conducted in Hawaii under seminatural conditions, we quantified the response of sexually mature, host‐seeking female melon flies, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae), to different types of visual and chemical host‐associated stimuli with the main aim of developing a monitoring device for females. Experiments were conducted using Tangletrap‐coated fruit mimics of either spherical (8 cm diameter) or cylindrical (4.3 cm diameter; 15 cm length) shapes coated with different artificial color pigments both at the ground level and at the tree‐canopy level so as to take into account the foraging behavior of adult melon flies. Females were particularly attracted to objects of spherical shape colored either yellow, white, or orange; these three pigments offered the highest reflectance values. Cucumber (Cucumis sativus L.) (Cucurbitaceae) odor was more attractive to females than odors of three other cultivated host fruit [zucchini, Cucurbita pepo L. var. medullosa Alef. (Cucurbitaceae); papaya, Carica papaya L. (Caricaceae); or tomato Solanum lycopersicum L. (Solanaceae)] or of ivy gourd [Coccinia grandis (L.) Voigt (Cucurbitaceae)], one of the major wild hosts of melon fly in Hawaii. A combination of both visual and olfactory stimuli was needed to elicit high levels of response compared to each stimulus offered alone. We discuss our results in relation to the potential implementation of improved female monitoring and/or attract‐and‐kill strategies for melon flies in Hawaii.  相似文献   

18.
Tapio Eeva  Esa Lehikoinen 《Oecologia》1996,108(4):631-639
We studied nestling growth, growth abnormalities, mortality and breeding success of two hole-nesting passerines, the great tit (Parus major) and the pied fly-catcher (Ficedula hypoleuca), at 14 study sites around a copper smelter complex in Harjavalta, south-west Finland in 1991–1993. The main pollutants in the area are heavy metals and sulphuric oxides. Exposure of birds to heavy metals was shown by measuring their faecal concentrations. Copper, nickel and lead contents of nestling faeces were high near the factory and decreased with distance away from the pollution source. F. hypoleuca nestlings suffered high mortality very close to the factory complex, but did relatively well at all other sites. Breeding success of P. major was below background levels up to 3–4 km from the pollution source and nestlings grew poorly close to the factory. Growth abnormalities of legs and wings in F. hypoleuca nestlings were significantly more common near the factory than farther away. In contrast, F. hypoleuca nestlings grew equally well at all distances. The poor breeding success of F. hypoleuca close to the factory complex is probably related to the high amount of heavy metals in its diet, and low availability of calcium-rich food items may enhance this effect. We suggest that the poor breeding success of P. major is related to habitat changes that have taken place around the factory. The different responses of these two bird species are probably due to their different diet. Our results show convincingly that species-specific differences in response should be carefully considered when planning schemes for air pollution monitoring.  相似文献   

19.
We used logistic and Poisson regression models to determine factors of forest and landscape structure that influence the presence and abundance of rodent species in the rain forest of Ranomafana National Park in southeastern Madagascar. Rodents were collected using live-traps along a gradient of human disturbance. All five endemic rodent species (Nesomys rufus, N. audeberti, Eliurus tanala, E. minor and E. webbi) and the introduced rat Rattus rattus were captured in both secondary and primary forests, but the introduced Mus musculus was only trapped in secondary forest. The abundance of R. rattus increased with the level of habitat disturbance, and it was most common in the heavily logged secondary forest. Furthermore, the probability of the presence of R. rattus increased with decreasing distance from forest edge and decreasing canopy cover, while the probability of presence increased with increasing herbaceous cover, altitude and overstory tree height. The species was never observed farther than 500 m away from human habitation or camp-site. N. rufus prefered selectively-logged forest at altitudes above 900 m a.s.l. Its probability of presence increased with increasing canopy cover, herbaceous cover and distance from forest edge, and with decreasing density of fallen logs, overstory tree height and distance from human habitation. N. audeberti prefered heavily-logged areas, while E. tanala was the only species occurring along the entire range of forest disturbance. We suggest that in the Ranomafana National Park the spread of R. rattus is associated with deforestation.  相似文献   

20.
Question: What is the role of dispersal, persistent soil seed banks and seedling recruitment in population persistence of fleshy‐fruited obligate seeding plant species in fire‐prone habitats? Location: Southeastern Australia. Methods: We used a long‐term study of a shrubby, fleshy‐fruited Persoonia species (Proteaceae) to examine (1) seed removal from beneath the canopy of adult plants; (2) seedling recruitment after fire; (3) the magnitude and location of the residual soil seed bank; and (4) the implications for fire management of obligate seeding species. We used demographic sampling techniques combined with Generalised Linear Modelling and regression to quantify population changes over time. Results: Most of the mature fruits (90%) on the ground below the canopy of plants were removed by Wallabia bicolor (Swamp wallaby) with 88% of seeds extracted from W. bicolor scats viable and dormant. Wallabies play an important role in moving seeds away from parent plants. Their role in occasional long distance dispersal events remains unknown. We detected almost no seed predation in situ under canopies (< 1%). Seedling recruitment was cued to fire, with post‐fire seedling densities 6‐7 times pre‐fire adult densities. After fire, a residual soil seed bank was present, as many seeds (77‐100%) remained dormant and viable at a soil depth where successful future seedling emergence is possible (0‐5 cm). Seedling survival was high (> 80%) with most mortality within 2 years of emergence. Plant growth averaged 17 cm per year. The primary juvenile period of plants was 7–8 years, within the period of likely return fire intervals in the study area. We predicted that the study population increased some five‐fold after the wildfire at the site. Conclusions: Residual soil seed banks are important, especially in species with long primary juvenile periods, to buffer the populations against the impact of a second fire occurring before the seed bank is replenished.  相似文献   

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