Habitat Plots Research Articles

Large avian frugivores in the Philippines show linear responses to improvements in forest quality

Large avian frugivores are important in ecosystem function, but are seriously threatened across the tropics. To conserve them we must understand their habitat needs and the effects of improved forest management on individual species and the community as a whole. We recorded the presence/absence of 18 parrot, pigeon and hornbill species along nearly 500km of transects at 24 sites in Luzon, Philippines, and used logistic GLMMs to identify bird-habitat associations based on topographical, forest structure and floristic data taken at 1227 habitat plots. We then searched for more complex relationships and thresholds in species responses along forest quality/restoration gradients using GAMMs. Frugivore species richness was highest in forest with large-girthed trees, although some small-scale agricultural disturbance was tolerated or even favoured. Importantly, richness was highest in forests on flat ground, areas which are usually the first to be converted to agriculture. Individual species were positively associated with large trees but responses to floristic gradients were more variable. Very few species had complex relationships with forest quality; for the great majority, the probability of occurrence increased linearly along the forest quality/restoration gradient. While the precise benefits in terms of seed dispersal, and costs of management, at different points along the quality/restoration gradient are likely to be themselves complex, avian frugivores benefit proportionately from step improvements right along the gradient. Thus, any actions to improve forest quality on Luzon, from reforesting the most degraded lands to preventing degradation of relatively healthy forests, are likely to benefit frugivores.

Adult Movement Pattern and Habitat Preferences of the Maghribian EndemicGomphus lucasii(Odonata: Gomphidae)

The Algerian Cubtail (Gomphus lucasii Selys) (Odonata: Gomphidae) is a river-dwelling dragonfly and one of the least known gomphid in the Palearctic. A survey of the movement patterns and habitat requirements of adults was conducted in the largest currently known population, located in the Seybouse River (Northeast Algeria). Daily mark-release-resighting surveys along a 2.5 km stretch of the watercourse and within plots in terrestrial habitats were carried out; a total of 1,316 individuals were marked. The resighting rate along the watercourse was 8.13% and did not significantly vary with sex and age. Adult spatial distribution differed according to sex and age. Mature females were significantly further from the water than males. Mature males were observed not only along the watercourse but also far from the water, up to 450 m where reproductive pairs in copula were recorded. Preferred maturation and foraging sites were open grasslands and dense wheat fields. Philopatry to reproductive sites had a mean of 1.11%, while philopatry to emergence site was lower (0.4%) and noted only in males. The mean distance of natal dispersal (from emergence to reproductive areas) was 596.5 ± 4.94 m. The mean dispersal distance from one reproductive site to another was 180.97 ± 238.54 m. Both mature males and females preferred fast flowing water, but females were observed to oviposit in relatively small watercourses.

The effect of the construction and renovation of a highway bypass in Central Poland on the carabid beetle fauna (Coleoptera: Carabidae)

The aim of this research was to define the effect of the construction and renovation of a highway bypass around the town of Skepe on the environment and assemblages of carabid beetles. This four-year study was based on catching samples of beetles using pitfall traps. The traps were set first in 2008 and later from 2010 to 2012, after the renovation of the road, along roadside verges adjacent to two ca. 100-year-old pine forest stands, wet habitats and fallows of arable fields and inside these habitats about 25 m from the road (control plots). The carabids collected were identified to species and numbers of individuals and dominance values of each of the species were calculated for each study plot and each year. Furthermore, the dominance of the different species of plants was assessed. Numbers of species, numbers of individuals, percentage share of forest species and individuals, and Shannon diversity values of the carabid assemblages were analyzed. Multivariate statistical analyses (ordinations) were carried out using the dominance of the different species of carabids and using the ecological indicator values of plants as environmental factors. The construction of the bypass in 1987 resulted in more diversified carabid assemblages along the roadsides. Carabid fauna along the roadsides differed from that in the control plots in forests and in terms of some parameters from the control plots in wet habitats, but not statistical from the control plots in the fallow areas of arable fields. The renovation of the road 22 years after construction did not result in any significant changes in the characteristic parameters of the carabid assemblages along the roadsides, but gradient analysis indicated that it did have an effect. In terms of the environmental conditions of the habitats based on the plant associations occurring there the roadside habitats differed from the control plots in forests and wetlands. Since the number of sites studied is rather low, the results of this study have to be considered to be preliminary, but may provide research hypotheses for further research on highway roadsides.

Multiple assessments of succession rates on Mount St. Helens

Understanding what regulates successional recovery improves ecosystem management, but since facets of vegetation structure respond differentially to regulatory mechanisms and do not develop concurrently, multiple measures of succession rates are needed to fully describe recovery. Using permanent plots located across a disturbance gradient on Mount St. Helens, we explore factors that regulate succession rates and methods to assess them. Rates were assessed with eight criteria. Structural recovery was determined by cover accumulation. Floristic turnover was evaluated by trajectory complexity (community type turnover), time to reach 20 % similarity to initial conditions, mean plot similarity, regression of the similarity decay, Euclidean distance (ED) in detrended correspondence analysis (DCA) space, principal components analysis of the DCA space, and the slope of this regression. Cover recovery is related to impact intensity, while floristic changes were inversely related to impact intensity, modified by local conditions. Scour sites soon achieved maximum cover, but stress delayed floristic recovery. Development on lahars was inhibited by isolation. Pumice and protected blasted ridge sites developed quickly; rates were slowed by disturbance and enhanced in protected sites and where Lupinus lepidus thrived. Comparisons of plots in different habitats confirmed that recovery rates are slowed by stresses imposed by elevation, exposure, and infertility, by isolation and by disturbance. No single criterion can characterize succession rates comprehensively, but trajectory complexity, matrix similarity, and ED in DCA space offer critical insight to understand the interactive effects of environment and disturbance history on rates of successional recovery.

When do grazers accelerate or decelerate soil carbon and nitrogen cycling in tundra? A test of theory on grazing effects in fertile and infertile habitats

It is generally predicted that grazers enhance soil microbial activity and nutrient availability and promote soil bacteria in fertile ecosystems, but retard microbial activity and nutrient availability and promote soil fungi in infertile ecosystems. We tested these predictions in tundra by comparing grazing effects between fertile and infertile habitats and with/without nutrient manipulation by fertilization. Grazing decreased soil N content in fertile and in fertilized plots in infertile habitats while increased it in infertile tundra habitats, which directly opposed our prediction. We conclude that this unpredicted outcome probably resulted from nutrient transport between habitats. Also contrasting with our hypothesis, grazing increased fungal rather than bacterial abundance in fertilized plots at both habitats. In support with predictions, grazing increased microbial activity for soil C decomposition in fertile but decreased it in infertile habitats. The effect of grazing on soil C decomposition followed same patterns as grazer‐induced changes in the activity of β‐glucosidase, which is an extracellular enzyme synthesized by soil microorganisms for degrading soil cellulose. We suggest that the theoretical framework on grazer–soil interactions should incorporate microbial potential for extracellular enzyme production (‘microscale’ grazer effects) and nutrient translocation by grazers among habitats (‘macroscale’ grazer effects) as important mechanisms by which grazers influence soil processes and nutrient availability for plants at contrasting levels of habitat fertility.

Anurans of a threatened savanna area in western Brazil

The Upper Paraguay River Basin is located in the center of South America and harbors one of the largest wetland in the world, known as Pantanal. This floodplain is surrounded by uplands, which presently have most of their area converted into pastures or monocultures, besides being poorly known scientifically. Also, most of these upland areas are considered conservation priorities. Here we present a list of anuran species from a savanna-like area (municipality of Camapuã, state of Mato Grosso do Sul, Brazil) inserted in the uplands surrounding the Pantanal floodplain, in the Upper Taquari River sub-basin, and evaluate the effectiveness of the sampling effort. Data were obtained through active searches in 22 plots in aquatic habitats, during the rainy season (from December 2009 to April 2010). We found 26 species, in four families. Although sampling effort was found to sufficiently represent the local anuran assemblage, future inventories in this region should ideally include samplings during the dry and early rainy seasons, and include both active and passive capturing methods.

Airborne laser scanner (LiDAR) proxies for understory light conditions

Canopy cover and canopy closure are two closely related measures of vegetation structure. They are used for estimating understory light conditions and their influence on a broad range of biological components in forest ecosystems, from the demography and population dynamics of individual species to community structure. Angular canopy closure is more closely related to the direct and indirect light experienced by a plant or an animal than vertical canopy cover, but more challenging to estimate. We used airborne laser scanner (ALS) data to estimate canopy cover for 210 5-m radius vegetation plots in semi-open habitats and forests in protected nature areas in Denmark. The method was based on the area of Thiessen (Voronoi) polygons generated from the ALS points. We also estimated angular canopy closure by transforming ALS points from Cartesian to spherical coordinates, and calculating the percentage of azimuth and zenith angle intervals which contained points. We compared these estimates with field-based estimates using densiometer for 60 vegetation plots in forest. Finally, we compared ALS-based estimates of canopy cover and canopy closure to field-based estimates of understory light, based on the average Ellenberg indicator values for light for the plant species present in a given plot. The correlations of Ellenberg values with ALS-based canopy closure were higher (r2: 0.47) than those with ALS-based canopy cover (r2: 0.26) and densiometer readings (r2: 0.41) for the forest sites. ALS-based canopy closure is thus a reasonable indicator of understory light availability and has the advantage over field-based methods that it can be rapidly estimated for extensive areas.

Community Structure and Ecological and Behavioral Traits of Ants (Hymenoptera: Formicidae) in Massachusetts Open and Forested Habitats

Abstract - We investigated ant species richness, interspecific behavioral interactions, and community composition in adjacent forested and open habitat plots in two forest types of the northeastern United States: 1) the more common hemlock-White Pine forest studied at Harvard Forest Long Term Ecological Research Station in central Massachusetts, and T) the rare Pitch Pine barrens of Myles Standish State Forest in southeastern Massachusetts, which also provide habitat for multiple rare and endangered species. Overall, we found that species richness, behavioral interactions, and ecological traits vary between forested and adjacent open habitat plots. The number of species is five times higher per plot in the hemlock-White Pine open habitat (compared to forest habitat), but this pattern (i.e., higher species richness in open vs. forested plots) is not observed in the Pitch Pine barren site. Non-metric multidimensional scaling analyses suggest that community composition is significantly different between fore...

圈养大熊猫野化培训期的生境选择特征

大熊猫(<em>Ailuropoda melanoleuca</em>)是我国特有的珍稀物种,也是世界上最濒危的野生动物之一。为了将人工繁育的部分大熊猫个体重引入其历史分布区或复壮野生种群,中国保护大熊猫研究中心从2003年开始进行圈养大熊猫的野外放归工作,通过野化培训以提高圈养大熊猫适应和选择野外环境的能力。对野化培训大熊猫"淘淘"的生境选择研究表明:该野化培训大熊猫幼仔经常活动于新笋密度较大的区域[生境与对照:(2.68±1.14)对(1.58±0.66)],却避开成竹密度过大[(9.91±2.51)对(12.18±4.68)]、竹子较高[(4.57±1.09) m对(4.98±0.66) m]以及枯死竹过多[(2.52±0.86)对(3.39±1.33)]的区域;喜欢活动于离水源[(1.59±0.67)对(2.19±0.87)]和隐蔽场所较近[(5.37±2.14) m对(8.35±7.76)m],以及距离乔木较远[(3.09±0.69) m对(2.70±0.42) m]和郁闭度较低[(1.85±0.57)对(2.10±0.47)]的区域(<em>P</em> < 0.05),新笋密度大小是该栖息地在整个野化培训期间是否被利用的最重要因素。该野化培训大熊猫幼仔保持着与带仔母兽相近的生境选择特征,对竹子环境的选择也与卧龙野生大熊猫相似,野化培训对该大熊猫幼仔产生了积极的作用。野化培训大熊猫幼仔形成的家域和核域面积分别为9.21 hm² 和1.93 hm²,占野化培训圈面积的51.95%和10.89%,其中家域面积仅有卧龙野生大熊猫的1.4%-2.4%,所以在以后的野化培训过程中需要采取增加野化培训圈中环境丰富度等方式,促进野化培训大熊猫形成较大的家域面积。;The giant panda (<em>Ailuropoda melanoleuca</em>)is a rare endangered species listed on the IUCN(International Union for Conservation of Nature and Natural Resources)Red List of Threatened Species and in the Appendices of CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora). The giant panda has encountered risks of gene loss and local extinction of metapopulations due to habitat loss as a result of both biogeological and anthropologenic disturbance. One way to save endangered species is to reintroduce captive animals to sparsely populated regions of their historical distribution area. However, in order for reintroduction to succeed, captive animals must be able to select habitat that ensures their survival in the wild, a crucial skill that can be honed during pre-release training. We conducted research involving pre-release training of a giant panda in an enclosure in an area of natural habitat at the China Conservation and Research Center for the Giant Panda (CCRCGP) in Wolong Nature Reserve. We found that the panda selected areas with a high density of <em>Fargesia robusta </em>bamboo shoots (means±standard deviation of habitat plots and control plots: 2.68±1.14 vs. 1.58±0.66), but avoided areas with a high density of adult bamboo (9.91±2.51 vs. 12.18±4.68) dead bamboo (2.52±0.86 vs. 3.39±1.33) and areas with higher bamboo culms ((4.57±1.09) m vs. (4.98±0.66) m). The panda was found in areas near water ((1.59±0.67) m vs. (2.19±0.87) m) and shelter ((5.37±2.14) m vs. (8.35±7.76) m) more often than other areas, but avoided areas close to trees ((3.09±0.69) m vs. (2.70±0.42) m) and areas with higher canopy cover (1.85±0.57 vs. 2.10±0.47) (<em>P</em> < 0.05). Logistic regression showed that the density of new bamboo shoots was the main factor predicting habitat use by the pre-released giant panda. The pre-released giant panda had similar habitat selection patterns as its mother, suggesting that it may be able to learn skills from its mother, an important factor that can impact the success of the reintroduction. The pre-released giant panda also displayed similar habitat selection patterns as wild giant pandas in Wolong Nature Reserve, suggesting that it may be prepared for foraging in the wild. The fact that the pre-released giant panda selected areas close to the shelter suggests it might have learned predator avoidance skills from pre-release training, which could have a positive effect on its survival in the wild. Home range and home range core areas were 9.21 hm² and 1.93 hm², about 51.95% and 10.89% of the pre-release training enclosure respectively, while the home range was only 1.4%-2.4% of home ranges of wild giant pandas in Wolong Nature Reserve. It is essential to enrich the bamboo species richness of the pre-release training enclosure (such as by including <em>Bashania faberi </em>in the enclosure) in the future.

Changes in plant functional groups and species diversity under three grassland using modes in typical grassland area of Inner Mongolia, China

Aims Our objectives were to reveal changes in plant functional groups and species diversity under three grass-land using modes in typical steppe of Inner Mongolia, China. Methods Three plots in similar habitats were selected from the Hulunbeier steppe area of the Hui River National Nature Reserve: an meadow plot (controlled utilization), pasture plot (moderate utilization) and public pasture plot (severe utilization). Plots were 250 m × 250 m and consisted of three sample belts separated by 20 m. Each sample belt had eight 1 m × 1 m sample plots. Important findings There were differences in species composition and community characteristics of the func-tional groups. Shrubs and sub-shrubs combined were significantly different (p 0.05) among the plots, with the highest value in meadow. Perennial grasses were significantly different (p 0.05). Annual and biennial herbs combined had significant differences (p 0.05), with the highest value in the public pasture. The public pasture also had the highest percentage of the xerophyte functional group (50%) and the lowest mesoxerophyte and meso-phyte (19%), and differences were significant (p 0.05) among the plots. The biomass of shrubs and sub-shrubs were lower in all plots. The combined biomass of perennial grasses and forbs decreased with the increase in grassland use intensity among meadow, pasture and public pasture, while the combined biomass of annual and biennial herbs increased. With the increase in use intensity, the community structure and composition tended to become simplified and susceptible to change. Richness and diversity were lowest in the pasture and highest in meadow. Differences in evenness were not significant. The use of meadow contributed to improving the health of the grassland, but pasture and public pasture exhibited over-grazing phenomena. The public pasture had degraded significantly because of the uncertainty about property responsibility and ineffective management.

唐家河自然保护区高山姬鼠和中华姬鼠夏季生境选择的比较

Habitat selection among allied species is one of the key supports for niche theory in ecology.Line transects and systematic sampling was used to study habitat selection by Chevrier′s field mouse and the South China field mouse from June to August 2009.The two species are sympatric in the Tangjiahe Nature Reserve,Qingchuan County,Sichuan Province,China.We compared habitat plots used by both mammals and control plots reflecting the environment at large to investigate their habitat use patterns.140 plots were measured totally.Of which,49 were used by Chevrier′s field mouse,41 were used by South China field mouse and the rest 50 were control plots.21 environmental variables potentially influencing their habitat selection were measured. In univariate analysis,16 variables were significantly different between plot groups,indicating the two mammals both have a distinct significant habitat preference.In addition,their selected habitats overlapped to some extent: they both preferred for habitats with gentle slopes,lower canopy height,significant fallen leaf ground coverage,a relatively higher proportion of open land,larger tree diameter at breast height,greater tree height,moderate shrub bamboo and herb density,and larger herb coverage when compared with the control plots. Significant differences in habitats selected indicated the two species have distinct habitat selection patterns.Chevrier′s field mouse occurred more frequently in habitats with lower elevations(about 1400 m) and taller herbs(about 16—30 cm),while South China field mouse occurred in habitats with higher elevations(about 1900 m) and shorter herbs(15 cm).Moreover,Chevrier′s field mouse preferred for habitats characteristic of evergreen and deciduous mixed broad-leaved forests,a shorter distance to water sources(50 m),vegetation in earlier successional stage(a small growth of trees) and shorter bamboo height(1 m).South China field proved to be more of a generalist with no prominent selectivity for the above ecological factors.This indicated the former′s habitat is more decentralized while Chevrier′s field mouse′s habitat is more centralized or its habitat use is more specialized. Stepwise discriminant function analysis showed the four variables of elevation,vegetation stage of succession,canopy,and herb height contributed more to habitat separation between the two small mammals than others.The higher discriminant function coefficients indicated the two species could coexist sympatrically. Habitat-use strategies are often cited as the means by which sympatric species avoid competition.Occupying separate microhabitats is common among sympatric species.It seemed that these two small mammals can coexist and evolve in the same region contributing to their temporal and spatial separation in habitat use.Since they have similar body sizes and breeding dates and share the same food sources,we hypothesize habitat separation between the two species may not have resulted from differences in physiological and ecological requirements,but from ecological or evolutionary adjustment to reduce interspecific competition.Based on our findings,different habitat management strategies should be adopted for the two species.

No Evidence of Local Adaptation inUniola paniculataL. (Poaceae), a Coastal Dune Grass

Abstract Studies of local adaptation generally investigate plants growing in relatively stable habitats. We asked whether populations of the long-lived clonal grass Uniola paniculata (Sea Oats) are locally adapted to microhabitats in the southeastern US coastal dunes, a habitat characterized by dynamic environmental gradients spanning relatively small distances. Although vegetative zonation is well characterized across these gradients, little is known about intraspecific evolutionary responses of species spanning the gradients. Plants from the foredune and backdune areas of the gradient (<10 m and 40–60 m from the shoreline, respectively) were reciprocally transplanted into experimental plots in both habitats. Although foredune plots were washed away by storms before harvest, the foredune plants demonstrated no early advantage in stem diameter or height growth, and thus there was no support for local adaptation in foredune plants. In the backdune plots, the backdune plants demonstrated no early growth adv...

Sedimentation effects on the benthos of streams and estuaries: a cross-ecosystem comparison

Connected ecosystems can be detrimentally affected by the same stressor, such as occurs when excess fine sediment moves from streams into estuaries. However, no previous study has directly compared sedimentation effects across these ecosystems. Responses of benthic macroinvertebrate communities to sedimentation were predicted to vary between streams and estuaries, because of intersystem differences in the physical environment and representation of species traits. To compare these responses, fine terrigenous sediment was added simultaneously to replicated plots in stream-run habitats and the adjacent estuary. Although sediment addition to streams caused reduced invertebrate densities after 1 week, no changes in taxon richness or consistent changes in community structure were detected, and densities had recovered another week later. In contrast, sediment addition to estuarine sites caused large declines in invertebrate densities and changes in community structure, which remained evident at the innermost sites 16 days after addition. Across both systems, sedimentation effects were detectable only for some of the common taxa, and biological traits were not predictive of effects. The potential for more severe effects in estuaries should be considered when predicting the implications of land-use changes that may increase sedimentation, and when setting guidelines for maintaining stream and estuarine condition.

Summer habitat selection of alpine musk deer in Xinglongshan National Nature Reserve, Northwestern China

During July and August from 2006 to 2008, summer habitat selection was studied in Alpine musk deer (Moschus sifanicus) in Xinglongshan National Natural Reserve in northwestern China. In total, seventy one musk deer utilized habitat plots and 246 random habitat plots were surveyed. Seventeen habitat characteristics were recorded and compared between the two habitat types, using Mann-Whitney U test and chi-square to compare the differences between utilized and random habitat plots, and principal component analysis (PCA) to determine the main factors influencing the habitat selection of musk deer. Mann-Whitney U test and chi-square was conducted to test whether there was significant difference between utilized and random plots. The results showed that musk deer prefers habitat with taller arbor height (7.57 +/- 0.83 ) m, higher food-plants abundance (12.97 +/- 1.80), increasing foliage cover for concealment, lower water dispersion, and higher anthropogenic disturbance. Furthermore, PCA results suggested that the arbor characteristics (arbor canopy and arbor DBH), altitude characteristic, food characteristics (ground-plant cover and food-plant abundance) and shrub characteristics (shrub canopy, shrub height and related arbor density) influence summer habitat selection patterns of alpine musk deer in Xinglongshan National Nature Reserve. The general pattern of summer habitat utilization and selection of alpine musk deer is an adaptive strategy to the changing food, concealment, water source and the physical condition of summer habitat.

Effects of Japanese Barberry (Ranunculales: Berberidaceae) Removal and Resulting Microclimatic Changes on Ixodes scapularis (Acari: Ixodidae) Abundances in Connecticut, USA

Japanese barberry (Berberis thunbergii de Candolle) is a thorny, perennial, exotic, invasive shrub that is well established throughout much of the eastern United States. It can form dense thickets that limit native herbaceous and woody regeneration, alter soil structure and function, and harbor increased blacklegged tick (Ixodes scapularis Say) populations. This study examined a potential causal mechanism for the link between Japanese barberry and blacklegged ticks to determine if eliminating Japanese barberry could reduce tick abundance and associated prevalence of Borrelia burgdorferi (Johnson, Schmid, Hyde, Steigerwalt, and Brenner). Japanese barberry was controlled at five study areas throughout Connecticut; adult ticks were sampled over three years. Each area had three habitat plots: areas where barberry was controlled, areas where barberry remained intact, and areas where barberry was minimal or absent. Sampled ticks were retained and tested for B. burgdorferi presence. At two study areas, temperature and relative humidity data loggers were deployed in each of the three habitat plots over two growing seasons. Intact barberry stands had 280 ± 51 B. burgdorferi-infected adult ticks/ha, which was significantly higher than for controlled (121 ± 17/ha) and no barberry (30 ± 10/ha) areas. Microclimatic conditions where Japanese barberry was controlled were similar to areas without barberry. Japanese barberry infestations are favorable habitat for ticks, as they provide a buffered microclimate that limits desiccation-induced tick mortality. Control of Japanese barberry reduced the number of ticks infected with B. burgdorferi by nearly 60% by reverting microclimatic conditions to those more typical of native northeastern forests.

TREE FLORA ON FRESHWATER WET HABITATS IN LOWLAND OF BORNEO: DOES WETNESS COOL THE SITES?

SUZUKI, E. 2010. Tree flora on freshwater wet habitats in lowland of borneo: does wetness cool the sites?. Reinwardtia 13(2): 199-210. - The floristic records of lowland forests of Borneo in dry (not inundated) and wet (kerangas and peat swamp) habitats, and in montane forest of West Java were compared to clarify the characteristics of the flora in the lowland wet habitats. The data was flora of trees (DBH is equal to or more than 4.8 cm) in 12, 7, and 3 plots in dry lowland, wet lowland and mountain, respectively (20.9 ha in total). Plots in dry habitats had 42 to 53 families in 1 ha, except two plots on river banks (33 and 37 families). Plots in wet habitats and in mountain had 32 - 45 and 21 - 40 families, respectively. The clusters of plots in dendrogram using number of species in family mostly coincided with the difference in habitats. The preference for wet habitats existed in some families: Aquifoliaceae, Icacinaceae, Thymelaeaceae, Guttiferae, Myrtaceae, and Anacardiaceae though most families including Dipterocarpaceae and Euphorbiaceae had no tendency. Myristicaceae, Meliaceae, and Sapindaceae preferred dry habitats. Some species consisting of the flora of tropical mountains were found occasionaly in wet habitats of lowland though very rarely in dry habitats. There was a weak but singificant correlation between preference for wet habitats and abundance in Japanese tree flora of each family. These results suggest that the wet habitat where the forest floor is periodically filled with water has cooler environment than dry habitat, and families adapted cooler climate prefer the former.

What limits the spread of two congeneric butterfly species after their reintroduction: quality or spatial arrangement of habitat?

AbstractPopulation growth and spread of recently reintroduced species is crucial for the success of their reintroduction. We analysed what limits the spread of two congeneric butterfly species Maculinea teleius and Maculinea nausithous, over 10 years following their reintroduction. During this time, their distributions appeared to be limited to a few sites although it was thought that more suitable habitats were available. Thus, we question, does the quality or the spatial arrangement of their habitat limit their spread? Although adult individuals of both species can select high‐quality plots, we show that selection of suitable plots in the area of reintroduction is spatially constrained. A low colonization probability of unoccupied distant plots of high quality was found for both species. The abandonment of occupied plots in Ma. teleius was also found to be dependent on the distance to occupied plots. We conclude that the spatial distribution of the two species during the 10 years following reintroduction was limited by the spatial arrangement of their habitat, rather than by the availability of high‐quality plots. The spatial constraints in movement can explain observed source–sink structures when female butterflies deposit their eggs on low‐quality plots. We conclude that although these species have very similar life histories, they require different approaches to their conservation due to subtle differences in adult habitat use and movement. Conservation of Ma. teleius should concentrate on improving local habitat quality, whereas conservation of Ma. nausithous is predicted to be more effective by creating a spatial network of suitable habitat plots, such as along road verges.

Long‐Term Variation in Small Mammal Abundance in Forest and Savanna of Bolivian Cerrado

ABSTRACTSmall mammals were trapped annually in two savanna and two forest plots in cerrado habitats of Noel Kempff Mercado National Park, Santa Cruz, Bolivia, for 5–10 yr. Eighteen species were captured in forest and seven species in savanna. Species numbers and total number of individuals captured were tightly correlated. In forest, species and abundance varied interannually by up to fourfold in one plot and to 100‐fold in the other, and showed alternating highs and lows as is typical for small mammals. The largest faunal differences were due not to site differences, but to year differences, with markedly different patterns in forests and savannas. Abundance was not correlated with rainfall overall, but showed correlation in exceptional years of rainfall and ENSO drought. In savanna, species and overall abundance declined without recovery during 3 yr after reaching minimum numbers in 2004. One species, Cavia aperea, became extinct on both plots, and subsequently, apparently on the entire savanna. Both herbivorous and insectivorous species declined together. Rainfall, fire, and flooding do not seem to account for savanna rodent declines. I propose the novel hypothesis that smoke from anthropogenic burning raises nocturnal temperatures and prevents dew formation, and that a decrease in nightly dry season dewfall has been instrumental in rodent declines. Anecdotal and climatic data are consistent with this hypothesis, but it cannot yet be tested.

Changes of Grassland Vegetation in Surroundings of New Railway Flyover (Eastern Bohemia, Czech Republic). Part I: Plant Communities and Permanent Habitat Plots

Paper shows (1) the results based on vegetation mo nitoring during the time period 19752005 in the grassland segment of undulated landscape alo ng railway corridor close to village Dlouha T řebova (Usti nad Orlici district, Eastern Bohemia, C zech Republic). Survey was focused on the meadow communities, identification of phycenological changes by comparison of historical phytosociological recor ds (1975) with the present ones (2005). (2) Actual releves taken within transect design sho wed that there is direct dependence between the meadow species composition and soil moisture gradient. Along the soil moisture gradient different formations can be found : Carex acuta communities occupying the wet sites close to river bank with high groundw ater table, followed by wet Calthion meadows with Cirsium rivulare in mosaic with Holcus lanatus formation on drier microsites. Arrhenatherum elatius stands grow in mesic conditions in contact with Calthion wet meadows. Dry sites on high slope are dominated by Festuca rubra . There are also some plant species of semi-thermophilous flora and species that prefer more acid soil reaction as a part of grassland complex. Meadow bio topes which were not affected by site alteration during bridge building, and communities with Carex acuta seem to be relatively stable in time. There are two populations of protec ted rare plant species in the locality: first an orchid Dactylorhiza majalis and the second Gentianopsis ciliata . (3) The railway reconstruction resulted mainly into degradation pro cesses of grassland sites which is documented by the sown plant mixture or ruderal pla nt assemblages.

Local above‐ground persistence of vascular plants: Life‐history trade‐offs and environmental constraints

AbstractQuestions: 1. Which plant traits and habitat characteristics best explain local above‐ground persistence of vascular plant species and 2. Is there a trade‐off between local above‐ground persistence and the ability for seed dispersal and below‐ground persistence in the soil seed bank?Locations: 845 long‐term permanent plots in terrestrial habitats across the Netherlands.Methods: We analysed the local above‐ground persistence of vascular plants in permanent plots (monitored once a year for ca. 16 year) with respect to functional traits and habitat preferences using survival statistics (Kaplan‐Meier analysis and Cox’ regression). These methods account for censored data and are rarely used in vegetation ecology.Results: Local above‐ground persistence is determined by both functional traits (especially the ability to form long‐lived clonal connections) and habitat preferences (especially nutrient requirements). Above‐ground persistence is negatively related to the ability for dispersal by wind and to the ability to accumulate a long‐term persistent soil seed bank (‘dispersal through time’) and is positively related to the ability for dispersal by water.Conclusions: Most species have a half‐life expectation over 15 years, which may contribute to time lags after changes in habitat quality or ‐configuration (‘extinction debt’). There is evidence for a trade‐off relationship between local above‐ground persistence and below‐ground seed persistence, while the relationship with dispersal in space is vector specific. The rate of species turnover increases with productivity.