Abstract. Forest structural complexity could be a good predictor of overall species diversity. Since tree harvesting has a negative effect on forest structure, it is important to analyse the effects of this disturbance on sensitive groups, as forest birds. In this study, we aimed to shed light on this aspect by analysing a set of univariate metrics in bird communities breeding in three coppiced forest habitats (coppiced of chestnut, coppiced of Turkey oak and high forest of beech) along a gradient in age classes. We hypothesised that, with increasing forest age, (i) breeding bird communities will progressively increase in diversity and, (ii) due to higher habitat heterogeneity due to coppicing, a higher species turnover in the first age classes could appear. In each forest habitat, all the metrics significantly increased, from recently coppiced to more mature forests, due to progressively higher availability of resources and niches along the gradient. When comparing paired forest habitats, abundance and richness were significantly different only in the two oldest age classes, highlighting that responses to different tree composition were more marked in the mature phase. In all forest habitats, species turnover (βw diversity) decreased progressively along the age gradient and was highest in the youngest age classes where many vegetation layers were present. Due to different coppice management practices, growth regime and consequent habitat heterogeneity, chestnuts showed a different pattern when compared to other forest habitats, with an increase in species turnover (βw diversity) at intermediate level. With increasing age of the forests, all the diversity metrics increased and species turnover decreased, highlighting the role of older forests as strategic habitats for highly structured bird communities.
{"title":"The older the richer: significant increase in breeding bird diversity along an age gradient of different coppiced woods","authors":"Lorenzo Mentil, C. Battisti, G. Carpaneto","doi":"10.5194/WE-18-143-2018","DOIUrl":"https://doi.org/10.5194/WE-18-143-2018","url":null,"abstract":"Abstract. Forest structural complexity could be a good predictor of overall species\u0000diversity. Since tree harvesting has a negative effect on forest structure,\u0000it is important to analyse the effects of this disturbance on sensitive\u0000groups, as forest birds. In this study, we aimed to shed light on this\u0000aspect by analysing a set of univariate metrics in bird communities\u0000breeding in three coppiced forest habitats (coppiced of chestnut, coppiced\u0000of Turkey oak and high forest of beech) along a gradient in age classes. We\u0000hypothesised that, with increasing forest age, (i) breeding bird communities will\u0000progressively increase in diversity and, (ii) due to higher habitat\u0000heterogeneity due to coppicing, a higher species turnover in the first age\u0000classes could appear. In each forest habitat, all the metrics significantly\u0000increased, from recently coppiced to more mature forests, due to\u0000progressively higher availability of resources and niches along the gradient.\u0000When comparing paired forest habitats, abundance and richness were\u0000significantly different only in the two oldest age classes, highlighting that\u0000responses to different tree composition were more marked in the mature\u0000phase. In all forest habitats, species turnover (βw diversity)\u0000decreased progressively along the age gradient and was highest in the\u0000youngest age classes where many vegetation layers were present. Due to\u0000different coppice management practices, growth regime and consequent habitat\u0000heterogeneity, chestnuts showed a different pattern when compared to other\u0000forest habitats, with an increase in species turnover (βw diversity)\u0000at intermediate level. With increasing age of the forests, all the diversity\u0000metrics increased and species turnover decreased, highlighting the role of\u0000older forests as strategic habitats for highly structured bird communities.\u0000","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"48 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2018-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84681195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. Polyploidization has been traditionally considered a phenomenon that mediates ecological differentiation; however, the adaptive value of genome duplications has been seldom explored. Natural or synthetic polyploids offer unique opportunities to experimentally quantify the immediate consequences of genome duplications in plant traits that may be involved with ecological differentiation. Jasione maritima is a diploid-tetraploid complex with cytotypes distributed allopatrically in an environmental gradient ideal for exploring the role of genome duplications in the success of polyploid lineages. However, like in numerous other polyploid complexes, neotetraploids of J. maritima have not been found in nature. In this study we developed a methodology to obtain synthetic tetraploids from seeds collected in wild diploid plants of J. maritima. We tested the effect of different colchicine concentrations and seedling ages in survival and polyploidization success of J. maritima seedlings, using flow cytometry to assess ploidy level and considering the population of origin. A methodology to synchronize seed germination was also explored. Synchronization of seed germination was best achieved using a cold treatment of 2 weeks before the transference to a growth chamber. An overall survival rate of 11.5±0.7 % and further tetraploid conversion of 35.6±2.9 % was obtained using 3-day-old seedlings of J. maritima. Survival rates were variable depending on colchicine treatment (the highest the most lethal) and seedling origin (i.e. population), while conversion rate was similar across these factors and high rates of tetraploid conversion were obtained. Considering that the main constraint was survival to the colchicine treatment, we suggest the use of the lowest colchicine concentration tested, i.e. 0.1 % colchicine. The use of older seedlings increased survival rates but, in many cases, compromised a complete tetraploid conversion, generating many diploid-tetraploid mixoploid plants.
{"title":"Production of synthetic tetraploids as a tool for polyploid research","authors":"M. Castro, S. Castro, J. Loureiro","doi":"10.5194/WE-18-129-2018","DOIUrl":"https://doi.org/10.5194/WE-18-129-2018","url":null,"abstract":"Abstract. Polyploidization has been traditionally considered a phenomenon that mediates\u0000ecological differentiation; however, the adaptive value of genome\u0000duplications has been seldom explored. Natural or synthetic polyploids offer\u0000unique opportunities to experimentally quantify the immediate consequences of\u0000genome duplications in plant traits that may be involved with ecological\u0000differentiation. Jasione maritima is a diploid-tetraploid complex\u0000with cytotypes distributed allopatrically in an environmental gradient ideal\u0000for exploring the role of genome duplications in the success of polyploid\u0000lineages. However, like in numerous other polyploid complexes, neotetraploids\u0000of J. maritima have not been found in nature. In this study we\u0000developed a methodology to obtain synthetic tetraploids from seeds collected\u0000in wild diploid plants of J. maritima. We tested the effect of\u0000different colchicine concentrations and seedling ages in survival and\u0000polyploidization success of J. maritima seedlings, using flow\u0000cytometry to assess ploidy level and considering the population of origin. A\u0000methodology to synchronize seed germination was also explored.\u0000Synchronization of seed germination was best achieved using a cold treatment\u0000of 2 weeks before the transference to a growth chamber. An overall survival\u0000rate of 11.5±0.7 % and further tetraploid conversion of 35.6±2.9 % was obtained using 3-day-old seedlings of J. maritima.\u0000Survival rates were variable depending on colchicine treatment (the highest\u0000the most lethal) and seedling origin (i.e. population), while conversion rate\u0000was similar across these factors and high rates of tetraploid conversion were\u0000obtained. Considering that the main constraint was survival to the colchicine\u0000treatment, we suggest the use of the lowest colchicine concentration tested,\u0000i.e. 0.1 % colchicine. The use of older seedlings increased survival\u0000rates but, in many cases, compromised a complete tetraploid conversion,\u0000generating many diploid-tetraploid mixoploid plants.\u0000","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"10 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2018-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88635625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. Natural sceneries or single plants may have positive influences on human health. Here we show that plant species richness can positively influence recovery from stress. Meadow-like arrays of different species richness (1, 16, 32, 64 species) were presented to visitors (n=171) of a popular park in Zurich, Switzerland (one array per participant). Participants' systolic blood pressure was measured twice: directly after they had been stressed and once again after a 2 min post-stress relaxation period during which they looked at one of either the meadow-like arrangements of plants in pots or at bare ground, shielded on three sides by a tent-like structure. The decrease in blood pressure was larger when respondents could view an arrangement of plants instead of ground without vegetation. Relaxation was strongest at intermediate species richness (32 species). Age, gender, and a person's attachment to nature did not influence relaxation. Our results indicate that species-rich vegetation may contribute to recovery from stress which should be considered in landscape management and planning.
{"title":"The influence of plant species richness on stress recovery of humans","authors":"Petra Lindemann-Matthies, D. Matthies","doi":"10.5194/WE-18-121-2018","DOIUrl":"https://doi.org/10.5194/WE-18-121-2018","url":null,"abstract":"Abstract. Natural sceneries or single plants may have positive influences on human health. Here we show that plant species richness can positively influence recovery from stress. Meadow-like arrays of different species richness (1, 16, 32, 64 species) were presented to visitors (n=171) of a popular park in Zurich, Switzerland (one array per participant). Participants' systolic blood pressure was measured twice: directly after they had been stressed and once again after a 2 min post-stress relaxation period during which they looked at one of either the meadow-like arrangements of plants in pots or at bare ground, shielded on three sides by a tent-like structure. The decrease in blood pressure was larger when respondents could view an arrangement of plants instead of ground without vegetation. Relaxation was strongest at intermediate species richness (32 species). Age, gender, and a person's attachment to nature did not influence relaxation. Our results indicate that species-rich vegetation may contribute to recovery from stress which should be considered in landscape management and planning.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"68 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2018-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90253363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. L. Peláez, A. Valdecasas, D. Martinez, J. L. Horreo
Abstract. The genus Arion includes several slug species, some of which are considered to be a pest to both cultivated and wild flora. Within this genus, the Arion ater complex comprises two different morphological forms: Arion rufus and A. ater, but there is no consensus about their species status. Their phylogenetic relationships have been recently solved, both of them belonging to different phylogenetic clades, but their species status is still unclear (as different clades are not always different species). For this reason, the aim of this study was to precisely identify these species status by employing the up-to-date multi-rate Poisson tree processes (mPTP) methodology as well as the classic methodology of genetic distances, both of which have three different mitochondrial genes. Results confirmed that both A. ater and A. rufus are independent evolutionary clades, and the high genetic distances between them (K2P distances ranged between 9.1 and 16.4 %, depending on genes) together with mPTP analyses, supported the idea that the clades correspond to different species. Results will be useful for the classification of these specific species as well as for developing proper pest control methodologies and conservation policies in both cultivated and wild plants.
{"title":"Towards the unravelling of the slug A. ater–A. rufus complex (Gastropoda Arionidae): new genetic approaches","authors":"M. L. Peláez, A. Valdecasas, D. Martinez, J. L. Horreo","doi":"10.5194/WE-18-115-2018","DOIUrl":"https://doi.org/10.5194/WE-18-115-2018","url":null,"abstract":"Abstract. The genus Arion includes several slug species, some of which are\u0000considered to be a pest to both cultivated and wild flora. Within this genus,\u0000the Arion ater complex comprises two different morphological forms:\u0000Arion rufus and A. ater, but there is no consensus about\u0000their species status. Their phylogenetic relationships have been recently\u0000solved, both of them belonging to different phylogenetic clades, but their\u0000species status is still unclear (as different clades are not always different\u0000species). For this reason, the aim of this study was to precisely identify these species\u0000status by employing the up-to-date multi-rate Poisson tree processes (mPTP)\u0000methodology as well as the classic methodology of genetic distances, both of\u0000which have three different mitochondrial genes. Results confirmed that both\u0000A. ater and A. rufus are independent evolutionary clades,\u0000and the high genetic distances between them (K2P distances ranged between 9.1\u0000and 16.4 %, depending on genes) together with mPTP analyses, supported\u0000the idea that the clades correspond to different species. Results will be\u0000useful for the classification of these specific species as well as for\u0000developing proper pest control methodologies and conservation policies in\u0000both cultivated and wild plants.\u0000","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"48 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2018-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81388755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Carvalho, R. C. Martins, A. Portugal, M. T. Gonçalves
Abstract. Maritime pine forests are a major ecosystem throughout the Portuguese coast and are severely affected by the invasion of Acacia longifolia. The presented study investigated the diversity of ectomycorrhizal fungi (ECM) of major plant species in these ecosystems to find possible links between Pinus pinaster, three native Cistaceae shrubs and the Acacia invasive species. We successfully identified 13 ECM fungal taxa. Within those, two species from the order Helotiales were found in all plant species, and over half of the fungal ECM species found in Pinus pinaster were also common to the Cistaceae shrubs. Network analysis points to the Cistaceae shrubs having a central role in these below-ground communities, therefore enforcing the idea that they are key to these communities and should not be underestimated. Our results also point to the evolving role of invasive plant species in the ecosystem dynamics in the rhizosphere, which host fungal species that are common to native plants, although it is not yet clear whether these fungal taxa are native or a consequence of the presence of Acacia longifolia.
{"title":"Do mycorrhizal fungi create below-ground links between native plants and Acacia longifolia? A case study in a coastal maritime pine forest in Portugal","authors":"P. Carvalho, R. C. Martins, A. Portugal, M. T. Gonçalves","doi":"10.5194/WE-18-105-2018","DOIUrl":"https://doi.org/10.5194/WE-18-105-2018","url":null,"abstract":"Abstract. Maritime pine forests are a major ecosystem throughout the\u0000Portuguese coast and are severely affected by the invasion of Acacia longifolia.\u0000The presented study investigated the diversity of ectomycorrhizal\u0000fungi (ECM) of major plant species in these ecosystems to find possible links\u0000between Pinus pinaster, three native Cistaceae shrubs and the\u0000Acacia invasive species. We successfully identified 13 ECM fungal\u0000taxa. Within those, two species from the order Helotiales were found in all\u0000plant species, and over half of the fungal ECM species found in Pinus pinaster were also common to the Cistaceae shrubs. Network analysis points to\u0000the Cistaceae shrubs having a central role in these below-ground communities,\u0000therefore enforcing the idea that they are key to these communities\u0000and should not be underestimated. Our results also point to the evolving role\u0000of invasive plant species in the ecosystem dynamics in the rhizosphere, which\u0000host fungal species that are common to native plants, although it is not\u0000yet clear whether these fungal taxa are native or a consequence of the presence of\u0000Acacia longifolia.\u0000","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"21 1","pages":""},"PeriodicalIF":2.2,"publicationDate":"2018-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82679850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. Laboratory experiments with food-deprived larvae of odonates suggested that these predators may have the potential to control mosquito populations. However, it remains unclear whether larvae of odonates co-occur with mosquito larvae in the field and whether larvae of odonates reduce the density of mosquito larvae in the field. We exposed 35 water-filled concrete containers in the field in shady and sunny conditions. Some of these containers were partially covered (for simplicity called closed containers, allowing only mosquitoes to lay eggs), whereas others remained open. The density of mosquito larvae was higher in shaded containers and in closed containers. The multivoltine odonate Bradinopyga strachani colonized open containers and the occurrence of these predators resulted in a clear reduction of the mosquito population. Our results indicate that increasing the colonization of water bodies by Bradinopyga strachani is a promising strategy for controlling populations of mosquitoes.
{"title":"Effect of a dragonfly ( Bradinopyga strachani Kirby, 1900) on the density of mosquito larvae in a field experiment using mesocosms","authors":"Daniel Acquah-Lamptey, R. Brandl","doi":"10.5194/WE-18-81-2018","DOIUrl":"https://doi.org/10.5194/WE-18-81-2018","url":null,"abstract":"Abstract. Laboratory experiments with food-deprived larvae of odonates suggested that these predators may have the potential to control mosquito populations. However, it remains unclear whether larvae of odonates co-occur with mosquito larvae in the field and whether larvae of odonates reduce the density of mosquito larvae in the field. We exposed 35 water-filled concrete containers in the field in shady and sunny conditions. Some of these containers were partially covered (for simplicity called closed containers, allowing only mosquitoes to lay eggs), whereas others remained open. The density of mosquito larvae was higher in shaded containers and in closed containers. The multivoltine odonate Bradinopyga strachani colonized open containers and the occurrence of these predators resulted in a clear reduction of the mosquito population. Our results indicate that increasing the colonization of water bodies by Bradinopyga strachani is a promising strategy for controlling populations of mosquitoes.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"32 1","pages":"81-89"},"PeriodicalIF":2.2,"publicationDate":"2018-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82892457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. Acacia longifolia is an aggressive invader worldwide. This species was brought to Portugal by the forestry services and is now found throughout the country with very strong ecological and social impacts. Although several ecological and physiological studies have been carried out, molecular studies in this species are sparse. Particularly, genetic variability evaluation in invasive ranges clearly deserves more attention. The aim of this study was to evaluate the genetic diversity and the genetic differentiation among populations of the alien invasive A. longifolia under different Mediterranean conditions. For that we studied three sandy dune populations along the Portuguese coast: Osso da Baleia (mesomediterranean), Pinheiro da Cruz and Vila Nova de Milfontes (termomediterranean). All sampled acacia plants were located underneath a pine forest, with the exception of the latter case study, where we also sampled in a diversified habitat conditions associated with the margins of agriculture fields. According to the historical records, it was also possible to compare acacia samples from original plantations and recently invaded areas. We have used two molecular markers – inter-simple sequence repeats (ISSR) and microsatellites (SSR). ISSR analysis showed that A. longifolia populations at all sampled locations have similar levels of diversity and a relatively low differentiation ( ΦPT=0.135 ). However, samples tended to cluster according to the regional (macro-scale) collection site. Microsatellites confirmed this low differentiation pattern. Our results indicate that differences in phenology and reproductive success observed during a previous study cannot be accounted for by genetic diversity and differentiation alone. Furthermore, our results taken together with historical information of A. longifolia suggest a single original introduction and a subsequent acclimation process.
摘要金合欢是一种世界性的侵略性入侵者。这个物种是由林业部门带到葡萄牙的，现在遍布全国，具有很强的生态和社会影响。虽然已经进行了一些生态学和生理学的研究，但对该物种的分子研究却很少。特别是，入侵物种的遗传变异评估显然值得更多的关注。本研究旨在评价不同地中海条件下外来入侵长叶橐吾居群的遗传多样性和遗传分化。为此，我们研究了葡萄牙海岸的三个沙丘种群:Osso da Baleia(中地中海)，Pinheiro da Cruz和Vila Nova de Milfontes(中地中海)。除后一个案例研究外，所有的金合欢植物样本都位于松林下，我们在与农田边缘相关的多样化栖息地条件下进行了采样。根据历史记录，还可以比较原始种植园和最近入侵地区的金合欢样本。我们使用了两种分子标记-简单序列重复序列(ISSR)和微卫星(SSR)。ISSR分析显示。各采样点长叶属种群多样性水平相近，分化程度较低(ΦPT=0.135)。然而，根据区域(宏观尺度)的采集地点，样本倾向于聚集。微型卫星证实了这种低分化模式。我们的研究结果表明，在先前的研究中观察到的物候和生殖成功的差异不能仅仅用遗传多样性和分化来解释。此外，我们的研究结果与历史资料一起表明，长叶冷杉有一个单一的原始引种和随后的驯化过程。
{"title":"Genetic diversity and differentiation of invasive Acacia longifolia in Portugal","authors":"S. Vicente, C. Máguas, H. Trindade","doi":"10.5194/WE-18-91-2018","DOIUrl":"https://doi.org/10.5194/WE-18-91-2018","url":null,"abstract":"Abstract. Acacia longifolia is an aggressive invader worldwide. This\u0000species was brought to Portugal by the forestry services and is now\u0000found throughout the country with very strong ecological and social\u0000impacts. Although several ecological and physiological studies have\u0000been carried out, molecular studies in this species are\u0000sparse. Particularly, genetic variability evaluation in invasive\u0000ranges clearly deserves more attention. The aim of this study was to\u0000evaluate the genetic diversity and the genetic differentiation among\u0000populations of the alien invasive A. longifolia under\u0000different Mediterranean conditions. For that we studied three sandy\u0000dune populations along the Portuguese coast: Osso da Baleia\u0000(mesomediterranean), Pinheiro da Cruz and Vila Nova de Milfontes\u0000(termomediterranean). All sampled acacia plants were located\u0000underneath a pine forest, with the exception of the latter case\u0000study, where we also sampled in a diversified habitat conditions\u0000associated with the margins of agriculture fields. According to the\u0000historical records, it was also possible to compare acacia samples\u0000from original plantations and recently invaded areas. We have used\u0000two molecular markers – inter-simple sequence repeats (ISSR) and\u0000microsatellites (SSR). ISSR analysis showed that\u0000A. longifolia populations at all sampled locations have\u0000similar levels of diversity and a relatively low differentiation\u0000( ΦPT=0.135 ). However, samples tended to cluster\u0000according to the regional (macro-scale) collection\u0000site. Microsatellites confirmed this low differentiation\u0000pattern. Our results indicate that differences in phenology and\u0000reproductive success observed during a previous study cannot be\u0000accounted for by genetic diversity and differentiation\u0000alone. Furthermore, our results taken together with historical\u0000information of A. longifolia suggest a single original\u0000introduction and a subsequent acclimation process.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"171 1","pages":"91-103"},"PeriodicalIF":2.2,"publicationDate":"2018-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72681934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E. Deus, Joaquim S. Silva, H. Marchante, E. Marchante, Catarina Félix
Abstract. Plantations of Eucalyptus globulus Labill. have been expanding rapidly worldwide. The species is considered invasive in several regions. While in the native range, post-dispersal seed predation is known to severely limit eucalypt recruitment, there is no experimental evidence of seed predation in the introduced range. We hypothesised that E. globulus seeds largely escape predation in Portugal, which may explain its prolific recruitment in some locations. We tested this hypothesis in central Portugal by exposing E. globulus seeds to the local fauna. For comparison purposes, we also used seeds from locally common species: Acacia dealbata Link (alien, larger, elaiosome-bearing seeds) and Cistus salviifolius L. (native, similarly sized seeds). We installed 30 feeding stations across three study sites, each one dominated by one study species. Each feeding station featured four feeders with different animal-access treatments: invertebrates; vertebrates; full access; no access (control). We placed five seeds of each plant species every day in each feeder and registered the number of seeds missing, eaten and elaiosome detached over 9 summer days. Eucalyptus globulus seeds were highly attractive to fauna in the three sites. Nearly half of E. globulus seeds were predated or removed, thus contradicting our hypothesis. Surprisingly, E. globulus and A. dealbata seeds were used by animals in similar proportions and C. salviifolius seeds were the least preferred. Vertebrates were the predominant seed predators and preferred the alien seeds. Invertebrates used all seed species in similar proportions. We found spatial variation regarding the predominant type of seed predators and the levels of seed predation according to the following patterns: predominance of vertebrates; predominance of invertebrates; negligible seed predator activity. Locations with negligible seed predation were abundant and scattered across the study area. Such spatial variation may help to explain the heterogeneous recruitment patterns of E. globulus seedlings found in previous studies.
{"title":"Are post-dispersed seeds of Eucalyptus globulus predated in the introduced range? Evidence from an experiment in Portugal.","authors":"E. Deus, Joaquim S. Silva, H. Marchante, E. Marchante, Catarina Félix","doi":"10.5194/WE-18-67-2018","DOIUrl":"https://doi.org/10.5194/WE-18-67-2018","url":null,"abstract":"Abstract. Plantations of Eucalyptus globulus Labill. have been\u0000expanding rapidly worldwide. The species is considered invasive in several\u0000regions. While in the native range, post-dispersal seed predation is known to\u0000severely limit eucalypt recruitment, there is no experimental evidence of\u0000seed predation in the introduced range. We hypothesised that\u0000E. globulus seeds largely escape predation in Portugal, which may\u0000explain its prolific recruitment in some locations. We tested this hypothesis\u0000in central Portugal by exposing E. globulus seeds to the local\u0000fauna. For comparison purposes, we also used seeds from locally common\u0000species: Acacia dealbata Link (alien, larger, elaiosome-bearing\u0000seeds) and Cistus salviifolius L. (native, similarly sized seeds). We\u0000installed 30 feeding stations across three study sites, each one dominated\u0000by one study species. Each feeding station featured four feeders with\u0000different animal-access treatments: invertebrates; vertebrates; full access;\u0000no access (control). We placed five seeds of each plant species every day in\u0000each feeder and registered the number of seeds missing, eaten and\u0000elaiosome detached over 9 summer days. Eucalyptus globulus seeds were highly attractive to fauna in the\u0000three sites. Nearly half of E. globulus seeds were predated or\u0000removed, thus contradicting our hypothesis. Surprisingly,\u0000E. globulus and A. dealbata seeds were used by animals in\u0000similar proportions and C. salviifolius seeds were the least\u0000preferred. Vertebrates were the predominant seed predators and preferred the\u0000alien seeds. Invertebrates used all seed species in similar proportions. We\u0000found spatial variation regarding the predominant type of seed predators and\u0000the levels of seed predation according to the following patterns:\u0000predominance of vertebrates; predominance of invertebrates; negligible seed\u0000predator activity. Locations with negligible seed predation were abundant and\u0000scattered across the study area. Such spatial variation may help to explain\u0000the heterogeneous recruitment patterns of E. globulus seedlings\u0000found in previous studies.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"309 1","pages":"67-79"},"PeriodicalIF":2.2,"publicationDate":"2018-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74399535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. Land use change can affect biodiversity, and this has an impact on ecosystem services (ESs), but the relationships between biodiversity and ESs are complex and poorly understood. Biodiversity is declining due to the abandonment of extensively grazed semi-natural grasslands. We therefore aim to explore relationships between biodiversity and ESs provided by extensively managed semi-natural grasslands. Focusing on vascular plant species richness, as well as the ESs fodder quantity, quality, and stability, allergy control, climate regulation, nutrient cycling, pollination, and aesthetic appreciation, we carried out botanical field surveys of 28 paired extensively grazed and abandoned semi-natural grassland plots, with four subplots of 4 m 2 in each plot. The management of the semi-natural grasslands is and has been at low intensity. We calculated the influence of abandonment on the ES indicators, measured the correlation between the biodiversity measure of vascular plant species richness and ES indicators, and finally determined how the relationships between plant species richness and the ES indicators were affected by the cessation of the extensive management. ES indicators are often, but not always, positively correlated with species richness. Cessation of extensive grazing has both negative and positive effects on ES indicators but the relationships between species richness and ES indicators are often different in extensively managed and abandoned semi-natural grasslands. The relationships between species richness and ES indicators are less pronounced in the extensively managed semi-natural grassland than for the abandoned. One possible reason for this outcome is high functional redundancy in the extensively managed semi-natural grasslands.
{"title":"The relationships between biodiversity and ecosystem services and the effects of grazing cessation in semi-natural grasslands","authors":"S. Wehn, K. Hovstad, L. Johansen","doi":"10.5194/WE-18-55-2018","DOIUrl":"https://doi.org/10.5194/WE-18-55-2018","url":null,"abstract":"Abstract. Land use change can affect biodiversity, and this has an impact on ecosystem\u0000services (ESs), but the relationships between biodiversity and ESs are\u0000complex and poorly understood. Biodiversity is declining due to the\u0000abandonment of extensively grazed semi-natural grasslands. We therefore aim to explore relationships between biodiversity and ESs\u0000provided by extensively managed semi-natural grasslands. Focusing on vascular\u0000plant species richness, as well as the ESs fodder quantity, quality, and stability,\u0000allergy control, climate regulation, nutrient cycling, pollination, and\u0000aesthetic appreciation, we carried out botanical field surveys of 28 paired\u0000extensively grazed and abandoned semi-natural grassland plots, with four\u0000subplots of 4 m 2 in each plot. The management of the semi-natural\u0000grasslands is and has been at low intensity. We calculated the influence of\u0000abandonment on the ES indicators, measured the correlation between the\u0000biodiversity measure of vascular plant species richness and ES indicators,\u0000and finally determined how the relationships between plant species richness\u0000and the ES indicators were affected by the cessation of the extensive\u0000management. ES indicators are often, but not always, positively correlated with species\u0000richness. Cessation of extensive grazing has both negative and positive\u0000effects on ES indicators but the relationships between species richness and\u0000ES indicators are often different in extensively managed and abandoned\u0000semi-natural grasslands. The relationships between species richness and ES\u0000indicators are less pronounced in the extensively managed semi-natural\u0000grassland than for the abandoned. One possible reason for this outcome is\u0000high functional redundancy in the extensively managed semi-natural\u0000grasslands.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"14 1","pages":"55-65"},"PeriodicalIF":2.2,"publicationDate":"2018-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90507158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. Acacia longifolia, a native legume from Australia, has been introduced in many European countries and elsewhere, thus becoming one of the most important global invasive species. In Europe, its flowering occurs in a period unsuitable for insect activity: nonetheless it is considered entomophilous. Floral traits of this species are puzzling: brightly coloured and scented as liked by insects, but with abundant staminate small-sized flowers and relatively small pollen grains, as it is common in anemophilous species. Invasion processes are especially favoured when reshaping local ecological networks, thus the interest in understanding pollination syndromes associated with invasive plant species that may facilitate invasiveness. Moreover, a striking difference exists between its massive flowering and relatively poor seed set. We introduced a novel approach: first, we consider the possibility that a part of the pollination success is carried on by wind and, second, we weighted the ethological perspective of the main pollinator. During the flowering season of A. longifolia (February–April 2016), we carried on exclusion experiments to detect the relative contribution of insects and wind. While the exclusion experiments corroborated the need for pollen vectors, we actually recorded a low abundance of insects. The honeybee, known pollinator of acacias, was relatively rare and not always productive in terms of successful visits. While wind contributed to seed set, focal observations confirmed that honeybees transfer pollen when visiting both the inflorescences to collect pollen and the extrafloral nectaries to collect nectar. The mixed pollination strategy of A. longifolia may then be the basis of its success in invading Portugal's windy coasts.
{"title":"Why so many flowers? A preliminary assessment of mixed pollination strategy enhancing sexual reproduction of the invasive Acacia longifolia in Portugal","authors":"M. Giovanetti, M. Ramos, C. Máguas","doi":"10.5194/WE-18-47-2018","DOIUrl":"https://doi.org/10.5194/WE-18-47-2018","url":null,"abstract":"Abstract. Acacia longifolia, a native legume from Australia, has been\u0000introduced in many European countries and elsewhere, thus becoming one of the\u0000most important global invasive species. In Europe, its flowering occurs in a\u0000period unsuitable for insect activity: nonetheless it is considered\u0000entomophilous. Floral traits of this species are puzzling: brightly coloured\u0000and scented as liked by insects, but with abundant staminate\u0000small-sized flowers and relatively small pollen grains, as it is common in\u0000anemophilous species. Invasion processes are especially favoured when\u0000reshaping local ecological networks, thus the interest in understanding\u0000pollination syndromes associated with invasive plant species that may\u0000facilitate invasiveness. Moreover, a striking difference exists between its\u0000massive flowering and relatively poor seed set. We introduced a novel\u0000approach: first, we consider the possibility that a part of the pollination\u0000success is carried on by wind and, second, we weighted the ethological\u0000perspective of the main pollinator. During the flowering season of A. longifolia (February–April 2016), we carried on exclusion experiments to\u0000detect the relative contribution of insects and wind. While the exclusion\u0000experiments corroborated the need for pollen vectors, we actually recorded a\u0000low abundance of insects. The honeybee, known pollinator of acacias, was\u0000relatively rare and not always productive in terms of successful visits. While wind\u0000contributed to seed set, focal observations confirmed that honeybees transfer pollen when visiting both the inflorescences to collect pollen and\u0000the extrafloral nectaries to collect nectar. The mixed pollination strategy\u0000of A. longifolia may then be the basis of its success in invading\u0000Portugal's windy coasts.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"36 1","pages":"47-54"},"PeriodicalIF":2.2,"publicationDate":"2018-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75386644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：