The woody vegetation is an important plant community constituent of tropical inselbergs,yet it remains largely overlooked.These environments of high socio-cultural and ecological value face pressures in many places,ma...The woody vegetation is an important plant community constituent of tropical inselbergs,yet it remains largely overlooked.These environments of high socio-cultural and ecological value face pressures in many places,mainly related to mining exploitation and fires.This study provides the first systematic overview of inselberg woody vegetation in the Brazilian Atlantic Forest.We used four inselbergs as models to characterize the composition and structure of the woody vegetation.In addition,the biomass and carbon storage were estimated using the general equations for tropical regions and carbon concentration values.Ten transects(50 m×2 m)were systematically installed on each inselberg,and all woody plants with a diameter at breast height≥5 cm were measured,registered,and identified.A total of 312 individuals belonging to 26 species,23 genera,and 14 families were found.The Fabaceae family and the genus Eugenia(Myrtaceae)exhibited a higher richness.The woody community's diameters ranged from 5.0 to 116.9 cm(with a mean of 23.9 cm),and heights ranged from 1.7 to 16.0 m(with a mean of 6.2 m).All specialist lithophyte woody species found on inselbergs are wind-dispersed.Among the endemic species of the Atlantic Forest,four were endemic to inselbergs,with Pseudobombax petropolitanum and Wunderlichia azulensis being threatened.A few species dominated the communities:P.petropolitanum,Guapira opposita,Amburana cearensis,and Tabebuia reticulata.Carbon accumulated in aboveground biomass ranged from 14 to 48 Mg ha-1,indicating variability in woody vegetation structure and growing conditions among inselbergs.Lastly,we highlight target species for potential use for inselberg vegetation restoration in stone mining areas in Atlantic Forest.展开更多
Tree growth synchrony serves as a valuable ecological indicator of forest resilience to climate stress and disturbances.However,our understanding of how increasing temperature affects tree growth synchrony during rapi...Tree growth synchrony serves as a valuable ecological indicator of forest resilience to climate stress and disturbances.However,our understanding of how increasing temperature affects tree growth synchrony during rapidly and slowly warming periods in ecosystems with varying climatic conditions remains limited.By using tree-ring data from temperate broadleaf(Fraxinus mandshurica,Phellodendron amurense,Quercus mongolica,and Juglans mandshurica)and Korean pine(Pinus koraiensis)mixed forests in northeast China,we investigated the effects of climate change,particularly warming,on the growth synchrony of five dominant temperate tree species across contrasting warm-dry and cool-wet climate conditions.Results show that temperature over water availability was the primary factor driving the growth and growth synchrony of the five species.Growth synchrony was significantly higher in warm-dry than in cool-wet areas,primarily due to more uniform climate conditions and higher climate sensitivity in the former.Rapid warming from the 1960s to the 1990s significantly enhanced tree growth synchrony in both areas,followed by a marked reversal as temperatures exceeded a certain threshold or warming slowed down,particularly in the warm-dry area.The growth synchrony variation patterns of the five species were highly consistent over time,although broadleaves exhibited higher synchrony than conifers,suggesting potential risks to forest resilience and stability under future climate change scenarios.Growing season temperatures and non-growing season temperatures and precipitation had a stronger positive effect on tree growth in the cool-wet area compared to the warm-dry area.High relative humidity hindered growth in the cool-wet area but enhanced it in the warm-dry area.Overall,our study highlights that the diversity and sensitivity of climate-growth relationships directly determine spatiotemporal growth synchrony.Temperature,along with water availability,shape long-term forest dynamics by affecting tree growth and synchrony.These results provide crucial insights for forest management practice to enhance structural diversity and resilience capacity against climate changeinduced synchrony shifts.展开更多
A new species of the genus Achalinus is described based on five specimens collected from the villages of Huangjialing and Fuxi, Huangshan, Anhui, China. It can be morphologically differentia ted from all the other spe...A new species of the genus Achalinus is described based on five specimens collected from the villages of Huangjialing and Fuxi, Huangshan, Anhui, China. It can be morphologically differentia ted from all the other species in Achalinus except for A. spinalis and A. werneri by the presence of a dotted black streak in the middle of the subcaudal. It can be distinguished from A. spinalis in that its two anterior temporals are in contact with eye, and A. werneri by its light brown flanks. The phylogenetic rela tionship of Achalinus was reconstructed using the mitochondrial locus of cytochrome coxidase subunit 1(CO1). The five new specimens form a monophyletic clade with strong support. The uncorrected p-dista nces between the new species and other representatives of Achalinus range from 13.6% to 21.7%. The recognition of the new species increases the number of described Achalinus species to 14.展开更多
Most studies that have examined mercury （Hg） contamination of fish have focused on game species feeding near the top of the food web, while studies that examine forage fish that feed near the base of the food web ar...Most studies that have examined mercury （Hg） contamination of fish have focused on game species feeding near the top of the food web, while studies that examine forage fish that feed near the base of the food web are rare. We conducted a survey of Hg contamination in three species of forage fish, brook silverside （Labidesthes sicculus）, threadfin shad （Dorosoma petenense） and gizzard shad （Dorosoma cepedianum）, from Caddo Lake, Texas, USA and found species-specific differences in Hg concentrations. We examined total length, age, trophic position （determined using δ15N）, and growth rate of forage fish as factors that could have influenced within-and between-species differences in Hg concentration. Total length and age were the best predictors of within-species differences in Hg concentration. Between-species differences in Hg concentrations were most strongly influenced by trophic position.展开更多
Over the past few decades, field studies conducted by Chinese primatologists have contributed significant new theoretical and empirical insights into the behavior, ecology, biology, genetics, and conservation of Ioris...Over the past few decades, field studies conducted by Chinese primatologists have contributed significant new theoretical and empirical insights into the behavior, ecology, biology, genetics, and conservation of Iorises, macaques, langurs, snubnosed monkeys, and gibbons. With the recent establishment and inaugural meeting of the China Primatological Society in 2017, China has emerged as a leading nation in primate research. Several research teams have conducted long-term studies despite the difficult challenges of habituating and observing wild primates Inhabiting mountainous temperate forests, and the fact that some 80% of China＇s 25-27 primate species are considered vulnerable, endangered, or critically endangered and are distributed in small isolated subpopulations. In going forward, it is recommended that primatologists in China increase their focus on seasonal differences in the social, ecological, physiological, and nutritional challenges primates face in exploiting high altitude and cold temperate forests. In addition, provisioning as a habitation tool should be minimized or eliminated, as it is difficult to control for its effects on group dynamics, patterns of habitat utilization, and feeding ecology. Finally in the next decade, Chinese primatologists should consider expanding the taxonomic diversity of species studied by conducting research in other parts of Asia, Africa, and the Neotropics.展开更多
The control of exotic and invasive species in areas undergoing recovery is a challenge for ecological restoration and this problem may be even greater in urbanized areas. This study evaluated the seed bank and seed ra...The control of exotic and invasive species in areas undergoing recovery is a challenge for ecological restoration and this problem may be even greater in urbanized areas. This study evaluated the seed bank and seed rain of a 5-year-old riparian forest located at the metropolitan region of Belo Horizonte in southeast Brazil, and verified changes over time in the abundance and species richness and whether planted species already were providing propagules to the site. At the forest, fifteen parcels of 100 m<sup>2</sup> were distributed randomly and soil samples were collected thrice (October 2011, March 2012 and July 2012) to evaluate the seed bank. Seed traps were installed in nine parcels to collect propagules over 1 year. Propagules were segregated and germinate at greenhouse. Species richness and abundance were estimated, and variance and similarity were quantified. In total, 86 species were recorded in the seed banks, 41.9% natives and 33.7% exotics, with the predominance of herbs (87.2%) and only 7% of trees. Species classified as weeds amounted to 52.3%. In the seed rain 642 seedlings germinated but they belonged to only 10 species, half of them were exotics. Regarding life forms, half of the species were arboreal and dominated the samples, highlighting the exotic species Melia azedarach. The species richness of the seed bank did not differ by season, unlike the seed rain which varied significantly by month. Seed bank and seed rain species had a very low floristic similarity with the list of planted species, suggesting that few planted trees had dispersed or were stocking propagules. Many non-planted species were recorded, mostly exotics and/or invasive that were probably derived from the surrounding urban matrix. These might interrupt the successional dynamics of the restoration forest and compromise the restoration process in the medium and long-terms. Our results highlight: (1) the importance of monitoring areas undergoing restoration; (2) that restoration methods and management actions directed to control exotic and invasive species are particularly important for sites in urban regions; and (3) the relevance of conserving forest fragments as sources of propagules for nearby areas.展开更多
Studies in recent years have shown that aquatic pollution by microplastics(MPs)can be considered to pose additional stress to amphibian populations.However,our knowledge of how MPs affect amphibians is very rudimentar...Studies in recent years have shown that aquatic pollution by microplastics(MPs)can be considered to pose additional stress to amphibian populations.However,our knowledge of how MPs affect amphibians is very rudimentary,and even more limited is our understanding of their effects in combination with other emerging pollutants.Thus,we aimed to evaluate the possible toxicity of polyethylene MPs(PE-MPs)(alone or in combination with a mix of pollutants)on the health of Physalaemus cuvieri tadpoles.After 30 days of exposure,multiple biomarkers were measured,including morphological,biometric,and developmental indices,behavioral parameters,mutagenicity,cytotoxicity,antioxidant and cholinesterase responses,as well as the uptake and accumulation of PE-MPs in animals.Based on the results,there was no significant change in any of the parameters measured in tadpoles exposed to treatments,but induced stress was observed in tadpoles exposed to PE-MPs combined with themixture of pollutants,reflecting significant changes in physiological and biochemical responses.Through principal component analysis(PCA)and integrated biomarker response(IBR)assessment,effects induced by pollutants in each test group were distinguished,confirming that the exposure of P.cuvieri tadpoles to the PE-MPs in combination with a mix of emerging pollutants induces an enhanced stress response,although the uptake and accumulation of PE-MPs in these animalswas reduced.Thus,our study provides newinsight into the danger to amphibians of MPs coexisting with other pollutants in aquatic environments.展开更多
Populations that have recently diverged offer a powerful model for studying evolution. Ecological differences are expected to generate divergent selection on multiple traits, including neurobiological ones. Animals mu...Populations that have recently diverged offer a powerful model for studying evolution. Ecological differences are expected to generate divergent selection on multiple traits, including neurobiological ones. Animals must detect, process, and act on information from their surroundings and the form of this information can be highly dependent on the environment. We might expect different environments to generate divergent selection not only on the sensory organs, but also on the brain regions responsible for processing sensory information. Here, we test this hypothesis using recently evolved reproductively isolated species pairs of threespine stickleback fish Gasterosteus aculeatus that have well-described differences in many morphological and behavioral traits corre- lating with ecological differences. We use a state-of-the-art method, magnetic resonance imaging, to get accurate volumetric data for 2 sensory processing regions, the olfactory bulbs and optic tecta. We found a tight correlation between ecology and the size of these brain regions relative to total brain size in 2 lakes with intact species pairs. Limnetic fish, which rely heavily on vision, had relatively larger optic tecta and smaller olfactory bulbs compared with benthic fish, which utilize olfaction to a greater extent. Benthic fish also had larger total brain volumes relative to their body size compared with limnetic fish. These differences were erased in a collapsed species pair in Enos Lake where anthropogenic disturbance has led to intense hybridization. Together these data indicate that evolution of sensory processing regions can occur rapidly and independently.展开更多
Leadership is a key issue in the study of collective behavior in social animals.Affiliation-leadership models predict that dyadic partner preferences based on grooming relationships or allianee formation positively af...Leadership is a key issue in the study of collective behavior in social animals.Affiliation-leadership models predict that dyadic partner preferences based on grooming relationships or allianee formation positively affect an in dividua I's decision to follow or support a con spec ific.In the case of many primate species,females without young infants are attracted to mother-infant dyads.However,the effects of mother-infant-female associations on affiliation-leadership models remain less clear.In free-rangi ng Tibeta n macaques Macaca thibetana,we used social network analysis to examine the importance of mother-inf a nt-adult female"social bridging eve nts as a predictor of who leads and who follows during group movement.Social bridging is a common behavior in Tibetan macaques and occurs whe n 2 adults,gen erally females,engage in coordinated in fa nt handling.Using eigenvector centrality coefficients of social bridging as a measure of social affiliation,we found that among lactating females,initiating bridging behavior with another female played a sign讦icant role in leadership success,with the assisting female following the mother during group movement.Among non lactati ng females,this was not the case.Our results in dicate that in fa nt attracti on can be a strong trigger in collective action and directing group movement in Tibetan macaques and provides benefits to mothers who require helpers and social support in order to ensure the safety of their infants.Our study provides new insights into the importance of the third-party effect in rethinking affiliation-leadership models in group-living animals.展开更多
Fire is a major type of disturbance that has important influences on ecosystem dynamics and carbon cycles.Yet our understanding of ecosystem fires and their carbon cycle consequences is still limited,largely due to th...Fire is a major type of disturbance that has important influences on ecosystem dynamics and carbon cycles.Yet our understanding of ecosystem fires and their carbon cycle consequences is still limited,largely due to the difficulty of large-scale fire monitoring and the complex interactions between fire,vegetation,climate,and anthropogenic factors.Here,using data from satellite-derived fire observations and ecosystem model simulations,we performed a comprehensive investigation of the spatial and temporal dynamics of China’s ecosystem fire disturbances and their carbon emissions over the past two decades(1997–2016).Satellite-derived results showed that on average about 3.47-4.53×10^(4) km^(2) of the land was burned annually during the past two decades,among which annual burned forest area was about 0.81-1.25×10^(4) km^(2),accounting for 0.33-0.51%of the forest area in China.Biomass burning emitted about 23.02 TgC per year.Compared to satellite products,simulations from the Energy Exascale Earth System Land Model(ELM)strongly overestimated China’s burned area and fire-induced carbon emissions.Annual burned area and fire-induced carbon emissions were high for boreal forest in Northeast China’s Daxing’anling region and subtropical dry forest in South Yunnan,as revealed by both the satellite product and the model simulations.Our results suggest that climate and anthropogenic factors play critical roles in controlling the spatial and seasonal distribution of China’s ecosystem fire disturbances.Our findings highlight the importance of multiple complementary approaches in assessing ecosystem fire disturbance and its carbon consequences.Further studies are required to improve the methods of observing and modelling China’s ecosystem fire disturbances,which will provide valuable information for fire management and ecosystem sustainability in an era when both human activities and the natural environment are rapidly changing.展开更多
Personality can play a large role in dispersal decisions, influencing how each individual estimates and values ex- pected costs versus benefits of ventnring out to explore the unknown. We contrast the impact of persis...Personality can play a large role in dispersal decisions, influencing how each individual estimates and values ex- pected costs versus benefits of ventnring out to explore the unknown. We contrast the impact of persistence on fitness using deci- sion theory models to examine the relative success of prospecting movement （which is a widespread behavior used by animals to explore available breeding habitat before determining where to settle） in different landscapes among individuals with different personalities. While evaluating trends in the costs and benefits of movement we provide a quantifiable measure of the impacts of relative tenacity in prospecting behavior on fitness gains/losses. Our model results predict that, regardless of landscape composi- tion, individuals with greater tenacity in prospecting strategy have reduced fitness gains relative to individuals who are more willing to both initiate novel strategies, but then also abandon the new strategy rapidly if initial search does not seem fruitful. We show that fitness gains from choosing an appropriate prospecting strategy （i.e. abandoning poor habitat or staying in rich habitat） can be very high, indicating a potentially large influence from personality on fitness. Importantly, the model predicts that relative fitness gains are highly dependent on the availability of high quality habitat in the landscape, even if the difference under varying fitness outcomes between poor and rich habitat was substantial展开更多
Attributing biological explanations to observed ecogeographical and ecological patterns require eliminating potential statistical and sampling artifacts as alternative explanations of the observed patterns.Here,we ass...Attributing biological explanations to observed ecogeographical and ecological patterns require eliminating potential statistical and sampling artifacts as alternative explanations of the observed patterns.Here,we assess the role of sample size,statistical power,and geographic inclusivity on the general validity and statistical significance of relationships between body size and latitude for 3 well-studied species of turtles.We extend those analyses to emphasize the importance of using statistically robust data in determining macroecological patterns.We examined intraspecific trends in body size with latitude in Chelydra serpentina,Chrysemys picta,and Trachemys scripts using Pearson's correlations,diagnostic tests for influential points,and resampling.Existing data were insufficient to ascertain a latitudinal trend in body size for C.serpentina or T.scripts.There was a significant relationship for C.picta,however,resampling analyses show that,on average,16 of the 23 available independent populations were needed to demonstrate a significant relationship and that at least 20 of 23 populations were required to obtain a statistically powerful correlation between body size and latitude.Furthermore,restricting the latitudes of populations resampled shows that body size trends of C.picta were largely due to leveraging effects of populations at the edge of the species range.Our results suggest that broad inferences regarding ecological trends in body size should be made with caution until underlying(intraspecific)patterns in body size can be statistically and conclusively demonstrated.展开更多
Some types of plant accumulate liquid in their inflorescences creating phytotelmata.These environments protect the flowers against florivory,although they may be colonized by aquatic or semiaquatic florivorous insect ...Some types of plant accumulate liquid in their inflorescences creating phytotelmata.These environments protect the flowers against florivory,although they may be colonized by aquatic or semiaquatic florivorous insect larvae,whose effects on the fitness of the plants remain unclear.We tested the hypothesis of floral antagonism by the occupants of phytotelmata,which predicts that florivory by the occupants of the phytotelmata represents a cost to the female fitness of the plant,reducing its fecundity.We manipulated experimentally the infestation by 3 florivores larvae species occupants of phytotelmata in inflorescences of Heliconia spathocircinata(Heliconiaceae)to test for negative direct trophic effects on the fecundity of the flowering and fruiting bracts.We found that the foraging of the hoverfly(Syrphidae)and moth(Lepidoptera)larvae in the inflorescences contributed to a decline in the fecundity of the plant.While the lepidopteran impacted fecundity when foraging in both flowering and fruiting bracts,the syrphid only affected the fruiting bracts,which indicates that the nectar and floral tissue are the principal resource exploited by the hoverfly.By contrast,soldier fly(Stratiomyidae)had a neutral effect on fecundity,while foraging in flowering or fruiting bracts.These findings corroborate our hypothesis,that herbivory by the larval occupants represents cost to the host plant having phytotelmata.The negative influence of this foraging on plant fecundity will nevertheless depend on the consequences of the exploitation of resources,which vary considerably in ephemeral habitats such as the phytotalmanta of flower parts.展开更多
Intraspecific diversity has widespread effects on ecological communities and ecosystems. To elucidate the mechanisms underlying these effects, manipulative studies require a rigorous and efficient empirical approach. ...Intraspecific diversity has widespread effects on ecological communities and ecosystems. To elucidate the mechanisms underlying these effects, manipulative studies require a rigorous and efficient empirical approach. Yet, replicating sufficient numbers of genetically identical individuals remains a challenge. As a result, we are limited in our understanding of the mechanisms underlying the ecological effects of intraspecific diversity. In contrast, large sample sizes are routinely produced in horticultural research using micropropagation, or tissue culture. In order to determine the potential usefulness of micropropagation technique for ecological studies, we investigated the efficiency and efficacy of micropropagation on the ecologically important non-model C4 grass species, Andropogon gerardii. Our preliminary results demonstrate that micropropagation is a rapid and effective technique for producing large numbers of genetically identical clones at up to 100 times the rate of traditional propagation. Key intraspecific differences among clones of A. gerardii were also retained through the micropropagation process. Given that traditional techniques used to test the effects of intraspecific diversity manipulations are time-limiting (greenhouse propagation) or can be biologically misrepresentative (seeds) for some species, we suggest that micropropagation might be a powerful tool for advancing ecological genetics studies in many plant systems.展开更多
Land use trajectory analysis provides both the time and kind of land cover changes to monitor land use dynamics. Land cover change trajectories for three different dates (1965, 1989 and 2014) extracted from satellite ...Land use trajectory analysis provides both the time and kind of land cover changes to monitor land use dynamics. Land cover change trajectories for three different dates (1965, 1989 and 2014) extracted from satellite images by vectorization of the thematic information were studied This study was carried out on a cultural landscape (S?o Carlos municipality, SP, Brazil) with three major land use-cover classes (forest, agriculture and other uses). The results showed the spatio temporal variability of landscape pattern and forest and agriculture change trajectories. Analysis based on these landscape trajectories demonstrates that agriculture and forest cover changes have been caused by human activities. The results reflect the conflicting interactions between environmental and human systems in the study area. A key question is that the pressure exerted on forest land use-cover depends on the incentives that move society from a conflicting relation with a municipal territory. A more sustainable landscape transition and trajectory for S?o Carlos municipality are extremely dependent on the regulatory role of the government through strategies related to the implementation of specific categories of legally protected areas (Legal Reserves and Areas of Permanent Preservation).展开更多
Recent evidence suggests that Brazilian Cerrado has been largely converted, mainly due to agribusiness activities and urbanization. Thus, the present work aimed to obtain the diagnosis of a watershed characterized by ...Recent evidence suggests that Brazilian Cerrado has been largely converted, mainly due to agribusiness activities and urbanization. Thus, the present work aimed to obtain the diagnosis of a watershed characterized by the expansion of sugar cane fields in the Brazilian Cerrado (Southeastern), employing integrity landscape indicators (Hemeroby, Urbanity Index, Landscape Vulnerability Index, and Water Quality Index) to verify the landscape naturalness, and the consequences of these actions to the ecosystem services provision. Remote sensing data for the years 1998, 2008, and 2018 were employed to verify the land-use changes in the Feijão River watershed (southeastern Brazil), as well as a matrix that considers the land use typologies and their capability to provide ecosystem services. The study area is classified as mixed land use, with the main categories related to agribusiness (sugar cane, pasture, bare soil). The Hemeroby and Urban Index denote naturalness declines over the years, and the observed patterns negatively impact ecosystem service provision. Landscape Vulnerability Index and Water Quality Index demonstrated that remaining vegetation cannot effectively retain pollutants, and severe impairments in the resilience of natural components of key ecosystem service providers (i.e. water and native vegetation) were observed. The results allowed the identification of priority areas for recovery and the maintenance of ecosystem services in agricultural lands.展开更多
The spatial distribution of plant species reveals how members of a population are horizontally organized in the environment. Individuals at different development stages can be influenced differently by abiotic and bio...The spatial distribution of plant species reveals how members of a population are horizontally organized in the environment. Individuals at different development stages can be influenced differently by abiotic and biotic factors because they are temporally separated. This may cause changes in spatial patterns in ontogenetic stages. The objectives of this study were to verify the pattern of spatial distribution of saplings and adults in Dalbergia cearensis Ducke and relate it to the pattern of seed dispersal. In two areas of 4.0 ha each, located in a Private Natural Heritage Reserve (RPPN) “Não Me Deixes”, there were counted all saplings and adults. This data were applied to the spatial analysis by distance indices, using the software Sadie Shell, version 8.0. The aggregation index (Ia) of adults was significant for both areas and showed aggregated distribution. D. cearensis saplings showed an aggregated distribution in the area I and area II. The dispersion distance was proportional for both areas, and the highest proportion of seeds was 10 - 20 m away from the center of the aggregation. Spatial analysis by distance indices showed an aggregated spatial distribution pattern for saplings and adults of D. cearensis.展开更多
Veredas are regarded as humid complexes of ecological, water and scenery significance in Cerrado biome related to water table outcrop. Direct alterations in these environments can lead to species diversity reduction a...Veredas are regarded as humid complexes of ecological, water and scenery significance in Cerrado biome related to water table outcrop. Direct alterations in these environments can lead to species diversity reduction and also facilitate biological invasion processes. Thus our study aims to investigate the natural regeneration, the coverage of woody vegetation and the invasive species in two sites in secondary successional stage in the central part of Cerrado biome. Our study was carried out at two sites located at Minas Gerais state, Brazil. We established plots randomly throughout transects laid perpendicularly to the vereda’s drain line. We used the line intercept method to analyze the vegetation coverage. We set five 10-m width transects in each of both areas, perpendicular to the vereda’s drain line to evaluate the distribution of invasive alien species in the two areas. The richness did not vary between communities (U = 67.50;p = 0.061);on the other hand we found significant difference in density estimates (U = 36.50;p = 0.002). We found significant difference between categories for soil coverage in both sites. Grasses showed the highest coverage when compared to the other categories (K = 45.06;p < 0.001 for site 1 and K = 67.47;p < 0.001 for site 2). We observed a zonation tendency in site 1, with a higher native grass coverage at middle and backwards zones (K = 7.734, p < 0.05). We only found Pinus caribaea Morelet individuals in the invasive species survey. We recorded 46 Pinus caribaea individuals at site 1 and 116 Pinus caribaea individuals at site 2. From the latter group we found 13 individuals within the vereda and 103 in the surrounding vegetation. Both sites have a high natural woody plant regeneration potential although the presence of alien grasses in the veredas’ edge and Pinus caribaea all over the humidity gradient highlights the vulnerability of these areas to biological invasion.展开更多
The thermal ecology of ectotherms has been studied for almost 2 centuries,but additional attention is currently being paid to it,to understand how organisms deal with the environment in a climate change context....The thermal ecology of ectotherms has been studied for almost 2 centuries,but additional attention is currently being paid to it,to understand how organisms deal with the environment in a climate change context.A consensus is still far away due to the large number of factors involved and their complex interactions.In this context,3 analyses in lacertid lizards were carried out:(i)a meta-analysis,to test for differences between body and air temperatures from 71 populations;(ii)a meta-analysis concerning correlations between body and air temperatures from 60 populations;and(iii)a multimodel inference of thermoregulation effectiveness indices from 45 populations.The importance of different factors,including body size,habitat,insularity,altitude,climate and season,was evaluated in all analyses to model the response variables.A strong seasonality effect was observed,with a consistent pattern of less effective thermoregulation in summer compared to other seasons.Altitude was the second most important factor,with a consistent higher thermoregulation effort in populations occurring at high elevations(>1000 m above sea level).Other factors,such as insularity or body size,can also be important,but did not exhibit a clear pattern.Finally,thermoregulation was less affected by climate and habitat type.展开更多
基金the project funding from Fundacao de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIGNo: APQ-02049-21)+3 种基金the National Council for Scientific and Technological Development (CNPqgrant 312567/2021-9)the Carlos Chagas Filho Foundation for Research Support of the State of Rio de Janeiro (FAPERJgrant E26/201.007/2022) for funding support
文摘The woody vegetation is an important plant community constituent of tropical inselbergs,yet it remains largely overlooked.These environments of high socio-cultural and ecological value face pressures in many places,mainly related to mining exploitation and fires.This study provides the first systematic overview of inselberg woody vegetation in the Brazilian Atlantic Forest.We used four inselbergs as models to characterize the composition and structure of the woody vegetation.In addition,the biomass and carbon storage were estimated using the general equations for tropical regions and carbon concentration values.Ten transects(50 m×2 m)were systematically installed on each inselberg,and all woody plants with a diameter at breast height≥5 cm were measured,registered,and identified.A total of 312 individuals belonging to 26 species,23 genera,and 14 families were found.The Fabaceae family and the genus Eugenia(Myrtaceae)exhibited a higher richness.The woody community's diameters ranged from 5.0 to 116.9 cm(with a mean of 23.9 cm),and heights ranged from 1.7 to 16.0 m(with a mean of 6.2 m).All specialist lithophyte woody species found on inselbergs are wind-dispersed.Among the endemic species of the Atlantic Forest,four were endemic to inselbergs,with Pseudobombax petropolitanum and Wunderlichia azulensis being threatened.A few species dominated the communities:P.petropolitanum,Guapira opposita,Amburana cearensis,and Tabebuia reticulata.Carbon accumulated in aboveground biomass ranged from 14 to 48 Mg ha-1,indicating variability in woody vegetation structure and growing conditions among inselbergs.Lastly,we highlight target species for potential use for inselberg vegetation restoration in stone mining areas in Atlantic Forest.
基金supported by the National Natural Science Foundation of China(Nos.42107476 and 42177421)the China Postdoctoral International Exchange Fellowship Program(No.PC2021099)+1 种基金the Science and Technology Innovation Program of Hunan Province(No.2020RC2058)the China Scholarship Council(CSC,No.202206600004,to D.Yuan).
文摘Tree growth synchrony serves as a valuable ecological indicator of forest resilience to climate stress and disturbances.However,our understanding of how increasing temperature affects tree growth synchrony during rapidly and slowly warming periods in ecosystems with varying climatic conditions remains limited.By using tree-ring data from temperate broadleaf(Fraxinus mandshurica,Phellodendron amurense,Quercus mongolica,and Juglans mandshurica)and Korean pine(Pinus koraiensis)mixed forests in northeast China,we investigated the effects of climate change,particularly warming,on the growth synchrony of five dominant temperate tree species across contrasting warm-dry and cool-wet climate conditions.Results show that temperature over water availability was the primary factor driving the growth and growth synchrony of the five species.Growth synchrony was significantly higher in warm-dry than in cool-wet areas,primarily due to more uniform climate conditions and higher climate sensitivity in the former.Rapid warming from the 1960s to the 1990s significantly enhanced tree growth synchrony in both areas,followed by a marked reversal as temperatures exceeded a certain threshold or warming slowed down,particularly in the warm-dry area.The growth synchrony variation patterns of the five species were highly consistent over time,although broadleaves exhibited higher synchrony than conifers,suggesting potential risks to forest resilience and stability under future climate change scenarios.Growing season temperatures and non-growing season temperatures and precipitation had a stronger positive effect on tree growth in the cool-wet area compared to the warm-dry area.High relative humidity hindered growth in the cool-wet area but enhanced it in the warm-dry area.Overall,our study highlights that the diversity and sensitivity of climate-growth relationships directly determine spatiotemporal growth synchrony.Temperature,along with water availability,shape long-term forest dynamics by affecting tree growth and synchrony.These results provide crucial insights for forest management practice to enhance structural diversity and resilience capacity against climate changeinduced synchrony shifts.
基金supported by Postdoctoral Research Program of Department of Human Resources and Social Security of Anhui Province (2020B422)Doctoral Research Starting Foundation of Anhui Normal University (752017)National Natural Science Foundation of China (NSFC 31471968)。
文摘A new species of the genus Achalinus is described based on five specimens collected from the villages of Huangjialing and Fuxi, Huangshan, Anhui, China. It can be morphologically differentia ted from all the other species in Achalinus except for A. spinalis and A. werneri by the presence of a dotted black streak in the middle of the subcaudal. It can be distinguished from A. spinalis in that its two anterior temporals are in contact with eye, and A. werneri by its light brown flanks. The phylogenetic rela tionship of Achalinus was reconstructed using the mitochondrial locus of cytochrome coxidase subunit 1(CO1). The five new specimens form a monophyletic clade with strong support. The uncorrected p-dista nces between the new species and other representatives of Achalinus range from 13.6% to 21.7%. The recognition of the new species increases the number of described Achalinus species to 14.
文摘Most studies that have examined mercury （Hg） contamination of fish have focused on game species feeding near the top of the food web, while studies that examine forage fish that feed near the base of the food web are rare. We conducted a survey of Hg contamination in three species of forage fish, brook silverside （Labidesthes sicculus）, threadfin shad （Dorosoma petenense） and gizzard shad （Dorosoma cepedianum）, from Caddo Lake, Texas, USA and found species-specific differences in Hg concentrations. We examined total length, age, trophic position （determined using δ15N）, and growth rate of forage fish as factors that could have influenced within-and between-species differences in Hg concentration. Total length and age were the best predictors of within-species differences in Hg concentration. Between-species differences in Hg concentrations were most strongly influenced by trophic position.
文摘Over the past few decades, field studies conducted by Chinese primatologists have contributed significant new theoretical and empirical insights into the behavior, ecology, biology, genetics, and conservation of Iorises, macaques, langurs, snubnosed monkeys, and gibbons. With the recent establishment and inaugural meeting of the China Primatological Society in 2017, China has emerged as a leading nation in primate research. Several research teams have conducted long-term studies despite the difficult challenges of habituating and observing wild primates Inhabiting mountainous temperate forests, and the fact that some 80% of China＇s 25-27 primate species are considered vulnerable, endangered, or critically endangered and are distributed in small isolated subpopulations. In going forward, it is recommended that primatologists in China increase their focus on seasonal differences in the social, ecological, physiological, and nutritional challenges primates face in exploiting high altitude and cold temperate forests. In addition, provisioning as a habitation tool should be minimized or eliminated, as it is difficult to control for its effects on group dynamics, patterns of habitat utilization, and feeding ecology. Finally in the next decade, Chinese primatologists should consider expanding the taxonomic diversity of species studied by conducting research in other parts of Asia, Africa, and the Neotropics.
基金supported by Coordination for the Improvement of Higher Educational Personnel(CAPES)
文摘The control of exotic and invasive species in areas undergoing recovery is a challenge for ecological restoration and this problem may be even greater in urbanized areas. This study evaluated the seed bank and seed rain of a 5-year-old riparian forest located at the metropolitan region of Belo Horizonte in southeast Brazil, and verified changes over time in the abundance and species richness and whether planted species already were providing propagules to the site. At the forest, fifteen parcels of 100 m<sup>2</sup> were distributed randomly and soil samples were collected thrice (October 2011, March 2012 and July 2012) to evaluate the seed bank. Seed traps were installed in nine parcels to collect propagules over 1 year. Propagules were segregated and germinate at greenhouse. Species richness and abundance were estimated, and variance and similarity were quantified. In total, 86 species were recorded in the seed banks, 41.9% natives and 33.7% exotics, with the predominance of herbs (87.2%) and only 7% of trees. Species classified as weeds amounted to 52.3%. In the seed rain 642 seedlings germinated but they belonged to only 10 species, half of them were exotics. Regarding life forms, half of the species were arboreal and dominated the samples, highlighting the exotic species Melia azedarach. The species richness of the seed bank did not differ by season, unlike the seed rain which varied significantly by month. Seed bank and seed rain species had a very low floristic similarity with the list of planted species, suggesting that few planted trees had dispersed or were stocking propagules. Many non-planted species were recorded, mostly exotics and/or invasive that were probably derived from the surrounding urban matrix. These might interrupt the successional dynamics of the restoration forest and compromise the restoration process in the medium and long-terms. Our results highlight: (1) the importance of monitoring areas undergoing restoration; (2) that restoration methods and management actions directed to control exotic and invasive species are particularly important for sites in urban regions; and (3) the relevance of conserving forest fragments as sources of propagules for nearby areas.
基金supporting the financing of this study(Process#307743/2018–7)the granting of research productivity grants to Dr.Malafaia G.(Proc.#307743/2018–7)and Dr.Melo e Silva D.(Process#307652/2018-1)+1 种基金for the scientific initiation scholarships to students Silva A.M.and Luz T.M.In addition,the authors thank the Federal Institute of Goiano(GO,Brazil)granting important financial assistance for the publication of this study(Proc.#23219.000139.2022-17).
文摘Studies in recent years have shown that aquatic pollution by microplastics(MPs)can be considered to pose additional stress to amphibian populations.However,our knowledge of how MPs affect amphibians is very rudimentary,and even more limited is our understanding of their effects in combination with other emerging pollutants.Thus,we aimed to evaluate the possible toxicity of polyethylene MPs(PE-MPs)(alone or in combination with a mix of pollutants)on the health of Physalaemus cuvieri tadpoles.After 30 days of exposure,multiple biomarkers were measured,including morphological,biometric,and developmental indices,behavioral parameters,mutagenicity,cytotoxicity,antioxidant and cholinesterase responses,as well as the uptake and accumulation of PE-MPs in animals.Based on the results,there was no significant change in any of the parameters measured in tadpoles exposed to treatments,but induced stress was observed in tadpoles exposed to PE-MPs combined with themixture of pollutants,reflecting significant changes in physiological and biochemical responses.Through principal component analysis(PCA)and integrated biomarker response(IBR)assessment,effects induced by pollutants in each test group were distinguished,confirming that the exposure of P.cuvieri tadpoles to the PE-MPs in combination with a mix of emerging pollutants induces an enhanced stress response,although the uptake and accumulation of PE-MPs in these animalswas reduced.Thus,our study provides newinsight into the danger to amphibians of MPs coexisting with other pollutants in aquatic environments.
文摘Populations that have recently diverged offer a powerful model for studying evolution. Ecological differences are expected to generate divergent selection on multiple traits, including neurobiological ones. Animals must detect, process, and act on information from their surroundings and the form of this information can be highly dependent on the environment. We might expect different environments to generate divergent selection not only on the sensory organs, but also on the brain regions responsible for processing sensory information. Here, we test this hypothesis using recently evolved reproductively isolated species pairs of threespine stickleback fish Gasterosteus aculeatus that have well-described differences in many morphological and behavioral traits corre- lating with ecological differences. We use a state-of-the-art method, magnetic resonance imaging, to get accurate volumetric data for 2 sensory processing regions, the olfactory bulbs and optic tecta. We found a tight correlation between ecology and the size of these brain regions relative to total brain size in 2 lakes with intact species pairs. Limnetic fish, which rely heavily on vision, had relatively larger optic tecta and smaller olfactory bulbs compared with benthic fish, which utilize olfaction to a greater extent. Benthic fish also had larger total brain volumes relative to their body size compared with limnetic fish. These differences were erased in a collapsed species pair in Enos Lake where anthropogenic disturbance has led to intense hybridization. Together these data indicate that evolution of sensory processing regions can occur rapidly and independently.
基金This work was funded by the Natural Science Foundation of China(Grant No.31801983,31971404,31772475,31372215)the Initial Foundation of Doctoral Scientific Research(Y040418135)the Program of Outstanding Young Teachers Training(Z010139011)in Anhui University,and China Scholarship Council.R.C.K.'s effort was supported in part by the Office of Research Infrastructure Programs(ORIP)of the National Institutes of Health(NIH)through Grant Number P5IODO 10425 to the Washington National Primate Research Center.
文摘Leadership is a key issue in the study of collective behavior in social animals.Affiliation-leadership models predict that dyadic partner preferences based on grooming relationships or allianee formation positively affect an in dividua I's decision to follow or support a con spec ific.In the case of many primate species,females without young infants are attracted to mother-infant dyads.However,the effects of mother-infant-female associations on affiliation-leadership models remain less clear.In free-rangi ng Tibeta n macaques Macaca thibetana,we used social network analysis to examine the importance of mother-inf a nt-adult female"social bridging eve nts as a predictor of who leads and who follows during group movement.Social bridging is a common behavior in Tibetan macaques and occurs whe n 2 adults,gen erally females,engage in coordinated in fa nt handling.Using eigenvector centrality coefficients of social bridging as a measure of social affiliation,we found that among lactating females,initiating bridging behavior with another female played a sign讦icant role in leadership success,with the assisting female following the mother during group movement.Among non lactati ng females,this was not the case.Our results in dicate that in fa nt attracti on can be a strong trigger in collective action and directing group movement in Tibetan macaques and provides benefits to mothers who require helpers and social support in order to ensure the safety of their infants.Our study provides new insights into the importance of the third-party effect in rethinking affiliation-leadership models in group-living animals.
基金funding was provided by the Carbon Mitigation Initiative(CMI)of the Princeton Environmental Institute,and by an Oak Ridge National Lab research subcontract to A.C.C.Y.and P.C.were supported by the fire_cci project(http://www.esa-fire-cci.org/)funded by the European Space AgencyS.R.was supported by a Graduate Research Fellowship from the U.S.National Science Foundation+1 种基金R.T.,J.M.,X.S.and D.R.were supported by the Terrestrial Ecosystem Science Scientific Focus Area(TES SFA)project and the Reducing Uncertainties in Biogeochemical Interactions through Synthesis and Computing Scientific Focus Area(RUBISCO SFA)project funded by the US Department of Energy,Office of Science,Office of Biological and Environmental ResearchOak Ridge National Laboratory is supported by the Office of Science of the US Department of Energy under Contract No.DE-AC05-00OR22725.
文摘Fire is a major type of disturbance that has important influences on ecosystem dynamics and carbon cycles.Yet our understanding of ecosystem fires and their carbon cycle consequences is still limited,largely due to the difficulty of large-scale fire monitoring and the complex interactions between fire,vegetation,climate,and anthropogenic factors.Here,using data from satellite-derived fire observations and ecosystem model simulations,we performed a comprehensive investigation of the spatial and temporal dynamics of China’s ecosystem fire disturbances and their carbon emissions over the past two decades(1997–2016).Satellite-derived results showed that on average about 3.47-4.53×10^(4) km^(2) of the land was burned annually during the past two decades,among which annual burned forest area was about 0.81-1.25×10^(4) km^(2),accounting for 0.33-0.51%of the forest area in China.Biomass burning emitted about 23.02 TgC per year.Compared to satellite products,simulations from the Energy Exascale Earth System Land Model(ELM)strongly overestimated China’s burned area and fire-induced carbon emissions.Annual burned area and fire-induced carbon emissions were high for boreal forest in Northeast China’s Daxing’anling region and subtropical dry forest in South Yunnan,as revealed by both the satellite product and the model simulations.Our results suggest that climate and anthropogenic factors play critical roles in controlling the spatial and seasonal distribution of China’s ecosystem fire disturbances.Our findings highlight the importance of multiple complementary approaches in assessing ecosystem fire disturbance and its carbon consequences.Further studies are required to improve the methods of observing and modelling China’s ecosystem fire disturbances,which will provide valuable information for fire management and ecosystem sustainability in an era when both human activities and the natural environment are rapidly changing.
文摘Personality can play a large role in dispersal decisions, influencing how each individual estimates and values ex- pected costs versus benefits of ventnring out to explore the unknown. We contrast the impact of persistence on fitness using deci- sion theory models to examine the relative success of prospecting movement （which is a widespread behavior used by animals to explore available breeding habitat before determining where to settle） in different landscapes among individuals with different personalities. While evaluating trends in the costs and benefits of movement we provide a quantifiable measure of the impacts of relative tenacity in prospecting behavior on fitness gains/losses. Our model results predict that, regardless of landscape composi- tion, individuals with greater tenacity in prospecting strategy have reduced fitness gains relative to individuals who are more willing to both initiate novel strategies, but then also abandon the new strategy rapidly if initial search does not seem fruitful. We show that fitness gains from choosing an appropriate prospecting strategy （i.e. abandoning poor habitat or staying in rich habitat） can be very high, indicating a potentially large influence from personality on fitness. Importantly, the model predicts that relative fitness gains are highly dependent on the availability of high quality habitat in the landscape, even if the difference under varying fitness outcomes between poor and rich habitat was substantial
文摘Attributing biological explanations to observed ecogeographical and ecological patterns require eliminating potential statistical and sampling artifacts as alternative explanations of the observed patterns.Here,we assess the role of sample size,statistical power,and geographic inclusivity on the general validity and statistical significance of relationships between body size and latitude for 3 well-studied species of turtles.We extend those analyses to emphasize the importance of using statistically robust data in determining macroecological patterns.We examined intraspecific trends in body size with latitude in Chelydra serpentina,Chrysemys picta,and Trachemys scripts using Pearson's correlations,diagnostic tests for influential points,and resampling.Existing data were insufficient to ascertain a latitudinal trend in body size for C.serpentina or T.scripts.There was a significant relationship for C.picta,however,resampling analyses show that,on average,16 of the 23 available independent populations were needed to demonstrate a significant relationship and that at least 20 of 23 populations were required to obtain a statistically powerful correlation between body size and latitude.Furthermore,restricting the latitudes of populations resampled shows that body size trends of C.picta were largely due to leveraging effects of populations at the edge of the species range.Our results suggest that broad inferences regarding ecological trends in body size should be made with caution until underlying(intraspecific)patterns in body size can be statistically and conclusively demonstrated.
基金Funding for this study was provided by the Brazilian Coordination for Higher Education Personnel Training(CAPES:Coordenacao de Aperfeic¸oamento de Pessoal de Nıvel Superior)for providing C.C.C.M.with a doctoral research scholarship(this study was financed in part by CAPES—Finance Code 001).The Rio de Janeiro State Research Foundation(FAPERJ:Fundacao Carlos Chagas Filho de Amparo aPesquisa do Estado do Rio de Janeiro)provided C.C.C.M.with a grant(DSC-10 process E_01/201.955/2017)supported the research of M.A.S.A.(CNE processes E-26/203191/2015,E-26/202.835/2018)The Brazilian National Research Council(CNPq:Conselho Nacional de Desenvolvimento Cientıfico e Tecnologico)provided M.A.S.A.with a research fellowship(PQ processes 305798/2014-6,306.579/2018-9).
文摘Some types of plant accumulate liquid in their inflorescences creating phytotelmata.These environments protect the flowers against florivory,although they may be colonized by aquatic or semiaquatic florivorous insect larvae,whose effects on the fitness of the plants remain unclear.We tested the hypothesis of floral antagonism by the occupants of phytotelmata,which predicts that florivory by the occupants of the phytotelmata represents a cost to the female fitness of the plant,reducing its fecundity.We manipulated experimentally the infestation by 3 florivores larvae species occupants of phytotelmata in inflorescences of Heliconia spathocircinata(Heliconiaceae)to test for negative direct trophic effects on the fecundity of the flowering and fruiting bracts.We found that the foraging of the hoverfly(Syrphidae)and moth(Lepidoptera)larvae in the inflorescences contributed to a decline in the fecundity of the plant.While the lepidopteran impacted fecundity when foraging in both flowering and fruiting bracts,the syrphid only affected the fruiting bracts,which indicates that the nectar and floral tissue are the principal resource exploited by the hoverfly.By contrast,soldier fly(Stratiomyidae)had a neutral effect on fecundity,while foraging in flowering or fruiting bracts.These findings corroborate our hypothesis,that herbivory by the larval occupants represents cost to the host plant having phytotelmata.The negative influence of this foraging on plant fecundity will nevertheless depend on the consequences of the exploitation of resources,which vary considerably in ephemeral habitats such as the phytotalmanta of flower parts.
文摘Intraspecific diversity has widespread effects on ecological communities and ecosystems. To elucidate the mechanisms underlying these effects, manipulative studies require a rigorous and efficient empirical approach. Yet, replicating sufficient numbers of genetically identical individuals remains a challenge. As a result, we are limited in our understanding of the mechanisms underlying the ecological effects of intraspecific diversity. In contrast, large sample sizes are routinely produced in horticultural research using micropropagation, or tissue culture. In order to determine the potential usefulness of micropropagation technique for ecological studies, we investigated the efficiency and efficacy of micropropagation on the ecologically important non-model C4 grass species, Andropogon gerardii. Our preliminary results demonstrate that micropropagation is a rapid and effective technique for producing large numbers of genetically identical clones at up to 100 times the rate of traditional propagation. Key intraspecific differences among clones of A. gerardii were also retained through the micropropagation process. Given that traditional techniques used to test the effects of intraspecific diversity manipulations are time-limiting (greenhouse propagation) or can be biologically misrepresentative (seeds) for some species, we suggest that micropropagation might be a powerful tool for advancing ecological genetics studies in many plant systems.
文摘Land use trajectory analysis provides both the time and kind of land cover changes to monitor land use dynamics. Land cover change trajectories for three different dates (1965, 1989 and 2014) extracted from satellite images by vectorization of the thematic information were studied This study was carried out on a cultural landscape (S?o Carlos municipality, SP, Brazil) with three major land use-cover classes (forest, agriculture and other uses). The results showed the spatio temporal variability of landscape pattern and forest and agriculture change trajectories. Analysis based on these landscape trajectories demonstrates that agriculture and forest cover changes have been caused by human activities. The results reflect the conflicting interactions between environmental and human systems in the study area. A key question is that the pressure exerted on forest land use-cover depends on the incentives that move society from a conflicting relation with a municipal territory. A more sustainable landscape transition and trajectory for S?o Carlos municipality are extremely dependent on the regulatory role of the government through strategies related to the implementation of specific categories of legally protected areas (Legal Reserves and Areas of Permanent Preservation).
文摘Recent evidence suggests that Brazilian Cerrado has been largely converted, mainly due to agribusiness activities and urbanization. Thus, the present work aimed to obtain the diagnosis of a watershed characterized by the expansion of sugar cane fields in the Brazilian Cerrado (Southeastern), employing integrity landscape indicators (Hemeroby, Urbanity Index, Landscape Vulnerability Index, and Water Quality Index) to verify the landscape naturalness, and the consequences of these actions to the ecosystem services provision. Remote sensing data for the years 1998, 2008, and 2018 were employed to verify the land-use changes in the Feijão River watershed (southeastern Brazil), as well as a matrix that considers the land use typologies and their capability to provide ecosystem services. The study area is classified as mixed land use, with the main categories related to agribusiness (sugar cane, pasture, bare soil). The Hemeroby and Urban Index denote naturalness declines over the years, and the observed patterns negatively impact ecosystem service provision. Landscape Vulnerability Index and Water Quality Index demonstrated that remaining vegetation cannot effectively retain pollutants, and severe impairments in the resilience of natural components of key ecosystem service providers (i.e. water and native vegetation) were observed. The results allowed the identification of priority areas for recovery and the maintenance of ecosystem services in agricultural lands.
文摘The spatial distribution of plant species reveals how members of a population are horizontally organized in the environment. Individuals at different development stages can be influenced differently by abiotic and biotic factors because they are temporally separated. This may cause changes in spatial patterns in ontogenetic stages. The objectives of this study were to verify the pattern of spatial distribution of saplings and adults in Dalbergia cearensis Ducke and relate it to the pattern of seed dispersal. In two areas of 4.0 ha each, located in a Private Natural Heritage Reserve (RPPN) “Não Me Deixes”, there were counted all saplings and adults. This data were applied to the spatial analysis by distance indices, using the software Sadie Shell, version 8.0. The aggregation index (Ia) of adults was significant for both areas and showed aggregated distribution. D. cearensis saplings showed an aggregated distribution in the area I and area II. The dispersion distance was proportional for both areas, and the highest proportion of seeds was 10 - 20 m away from the center of the aggregation. Spatial analysis by distance indices showed an aggregated spatial distribution pattern for saplings and adults of D. cearensis.
基金We would like to thank Duratex for funding the project of which this study is partWe are also thankful to the graduate Program in Ecology and Natural Resources Conservation and CAPES for the graduate scholarship provided.
文摘Veredas are regarded as humid complexes of ecological, water and scenery significance in Cerrado biome related to water table outcrop. Direct alterations in these environments can lead to species diversity reduction and also facilitate biological invasion processes. Thus our study aims to investigate the natural regeneration, the coverage of woody vegetation and the invasive species in two sites in secondary successional stage in the central part of Cerrado biome. Our study was carried out at two sites located at Minas Gerais state, Brazil. We established plots randomly throughout transects laid perpendicularly to the vereda’s drain line. We used the line intercept method to analyze the vegetation coverage. We set five 10-m width transects in each of both areas, perpendicular to the vereda’s drain line to evaluate the distribution of invasive alien species in the two areas. The richness did not vary between communities (U = 67.50;p = 0.061);on the other hand we found significant difference in density estimates (U = 36.50;p = 0.002). We found significant difference between categories for soil coverage in both sites. Grasses showed the highest coverage when compared to the other categories (K = 45.06;p < 0.001 for site 1 and K = 67.47;p < 0.001 for site 2). We observed a zonation tendency in site 1, with a higher native grass coverage at middle and backwards zones (K = 7.734, p < 0.05). We only found Pinus caribaea Morelet individuals in the invasive species survey. We recorded 46 Pinus caribaea individuals at site 1 and 116 Pinus caribaea individuals at site 2. From the latter group we found 13 individuals within the vereda and 103 in the surrounding vegetation. Both sites have a high natural woody plant regeneration potential although the presence of alien grasses in the veredas’ edge and Pinus caribaea all over the humidity gradient highlights the vulnerability of these areas to biological invasion.
基金The Biodiversity Survey and Assessment Project of the Ministry of Ecology and EnvironmentChina[grant numbers 2019HJ2096001006]TNC China Program[2002-2004]。
文摘野生灵长类夜宿地的利用方式可以明确地反映一个物种特有的生境利用方式和生存之道。2003年12月至2004年10月,我们利用可自动脱落GPS无线电项圈对云南省丽江市金丝厂的一个滇金丝猴(Rhinopithecus bieti)群体的活动进行了持续跟踪记录。本研究着重于对所研究猴群夜宿树的选择和夜宿地的利用方式的考查,并结合可能影响夜宿地选择和利用的环境因素,比如天气、季节、日均温度等做了系统分析。研究群计有180余只个体,家域面积约27.8 km^(2)。GPS项圈记录到夜宿树的有272个夜晚,由此我们确认了131个夜宿地。其中70个(54.3%)夜宿地仅利用了一次,剩余的则不同程度地多次利用(2~9次)。在这些重复利用的夜宿地中,持续利用同一夜宿点的情形共发生了19次,其中连续3个夜晚在同一夜宿地过夜的现象出现了3次,剩下的16次是连续利用同一夜宿地2次。这种连续利用同一夜宿地的情况占重复利用同一夜宿的7.0%,发生频率不高,而且几乎都出现在冬季(84.0%)。滇金丝猴对于同一夜宿地的重复造访的时间间隔约50 d。一旦发生连续重复利用的情况,猴群当天的移动距离显著缩短(527 m vs.884 m),降低了群体移动所必需的能量消耗。明显地,滇金丝猴夜宿点的选择受其当天下午和第二天早上觅食点的位置的影响。鉴于较大的群体和明显回避夜宿地重复利用的特性,提示这是猴群对家域内食物分布的行为响应,避免对同一地点的过度利用造成食物的不足。采用大量(131个)而分散的夜宿地利用方式会保证猴群能够获得充足的食物供应。此外,相较于其他树种,滇金丝猴更喜欢在云南铁杉(Tsuga dumosa)树上过夜,而且尽量不以夜宿点作为觅食点,可能与卫生和安全有关。
文摘The thermal ecology of ectotherms has been studied for almost 2 centuries,but additional attention is currently being paid to it,to understand how organisms deal with the environment in a climate change context.A consensus is still far away due to the large number of factors involved and their complex interactions.In this context,3 analyses in lacertid lizards were carried out:(i)a meta-analysis,to test for differences between body and air temperatures from 71 populations;(ii)a meta-analysis concerning correlations between body and air temperatures from 60 populations;and(iii)a multimodel inference of thermoregulation effectiveness indices from 45 populations.The importance of different factors,including body size,habitat,insularity,altitude,climate and season,was evaluated in all analyses to model the response variables.A strong seasonality effect was observed,with a consistent pattern of less effective thermoregulation in summer compared to other seasons.Altitude was the second most important factor,with a consistent higher thermoregulation effort in populations occurring at high elevations(>1000 m above sea level).Other factors,such as insularity or body size,can also be important,but did not exhibit a clear pattern.Finally,thermoregulation was less affected by climate and habitat type.
