scholarly journals Community-level reorganizations following migratory pollinator dynamics along a latitudinal gradient

2020 ◽  
Vol 287 (1930) ◽  
pp. 20200649 ◽  
Author(s):  
Ainhoa Magrach ◽  
Carlos Lara ◽  
Ubaldo Márquez Luna ◽  
Sergio Díaz-Infante ◽  
Ingrid Parker
Keyword(s):  
Fruit Set ◽  
Niche Overlap ◽  
Biodiversity Loss ◽  
Latitudinal Gradients ◽  
Migratory Species ◽  
Resident Species ◽  
Pollination Services ◽  
Community Persistence ◽  
Diversity Gradient ◽  
Diverse Communities

Predicting how communities re-arrange in response to changes in species composition remains a key challenge in ecology. Migratory species, which enter and leave communities across latitudinal gradients, offer us a unique opportunity to evaluate community- and species-level responses to a shift in community composition. We focused on a migratory hummingbird and the communities that host it along a latitudinal and species diversity gradient. Our results show higher niche overlap in more diverse communities, allowing resident species to compensate for the loss of the migrant in providing pollination services. Contrastingly, in less diverse communities, the migrant behaves as a specialist, monopolizing abundant resources. In its absence, its role is not fully covered by resident species, resulting in a decrease in the fruit set of the migrant's preferred plant species. These results help us understand the potential impacts of biodiversity loss and have important implications for community persistence given expected changes in the migratory behaviours of some species.

Pollen limitation and xenia effects in a cultivated mass-flowering tree, Macadamia integrifolia (Proteaceae)

2021 ◽  
Author(s):  
Stephen J Trueman ◽  
Wiebke Kämper ◽  
Joel Nichols ◽  
Steven M Ogbourne ◽  
David Hawkes ◽  
...  
Keyword(s):  
Food Production ◽  
Fruit Set ◽  
Pollen Limitation ◽  
Pollination Services ◽  
Mass Flowering ◽  
Shell Mass ◽  
Cross Pollination ◽  
Macadamia Integrifolia ◽  
Kernel Yield ◽  
Flowering Tree

Abstract Background and Aims Pollen limitation is most prevalent among bee-pollinated plants, self-incompatible plants, and tropical plants. However, we have very little understanding of the extent to which pollen limitation affects fruit set in mass-flowering trees despite tree crops accounting for at least 600 million tons of the 9,200 million tons of annual global food production. Methods We determined the extent of pollen limitation in a bee-pollinated, partially self-incompatible, subtropical tree by hand cross-pollinating the majority of flowers on mass-flowering macadamia (Macadamia integrifolia) trees that produce about 200,000–400,000 flowers. We measured tree yield and kernel quality and estimated final fruit set. We genotyped individual kernels by MassARRAY to determine levels of outcrossing in orchards and assess paternity effects on nut quality. Key Results Macadamia trees were pollen limited. Supplementary cross-pollination increased nut-in-shell yield, kernel yield and fruit set by as much as 97%, 109% and 92%, respectively. The extent of pollen limitation depended upon the proximity of experimental trees to trees of another cultivar because macadamia trees were highly outcrossing. Between 84% and 100% of fruit arose from cross-pollination, even at 200 m (25 rows) from orchard blocks of another cultivar. Large variations in nut-in-shell mass, kernel mass, kernel recovery and kernel oil concentration were related to differences in fruit paternity, including between self-pollinated and cross-pollinated fruit, thus demonstrating pollen-parent effects on fruit quality, i.e. xenia. Conclusions This study is the first to demonstrate pollen limitation in a mass-flowering tree. Improved pollination led to increased kernel yield of 0.31–0.59 tons per hectare, which equates currently to higher farm-gate income of approximately US3,720–US7,080 per hectare. The heavy reliance of macadamia flowers on cross-pollination and the strong xenia effects on kernel mass demonstrate the high value that pollination services can provide to food production.

scholarly journals Pollination by hoverflies in the Anthropocene

2020 ◽  
Vol 287 (1927) ◽  
pp. 20200508 ◽  
Author(s):  
Toby Doyle ◽  
Will L. S. Hawkes ◽  
Richard Massy ◽  
Gary D. Powney ◽  
Myles H. M. Menz ◽  
...  
Keyword(s):  
Crop Protection ◽  
Ecosystem Functions ◽  
Anthropogenic Change ◽  
Migratory Species ◽  
Long Distance ◽  
Pollination Services ◽  
Relative Contribution ◽  
Or Groups ◽  
Large Populations ◽  
Global Food

Pollinator declines, changes in land use and climate-induced shifts in phenology have the potential to seriously affect ecosystem function and food security by disrupting pollination services provided by insects. Much of the current research focuses on bees, or groups other insects together as ‘non-bee pollinators’, obscuring the relative contribution of this diverse group of organisms. Prominent among the ‘non-bee pollinators’ are the hoverflies, known to visit at least 72% of global food crops, which we estimate to be worth around US$300 billion per year, together with over 70% of animal pollinated wildflowers. In addition, hoverflies provide ecosystem functions not seen in bees, such as crop protection from pests, recycling of organic matter and long-distance pollen transfer. Migratory species, in particular, can be hugely abundant and unlike many insect pollinators, do not yet appear to be in serious decline. In this review, we contrast the roles of hoverflies and bees as pollinators, discuss the need for research and monitoring of different pollinator responses to anthropogenic change and examine emerging research into large populations of migratory hoverflies, the threats they face and how they might be used to improve sustainable agriculture.

scholarly journals Environmental and ecological factors mediate taxonomic composition and body size of polyplacophoran assemblages along the Peruvian Province

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Christian M. Ibáñez ◽  
Melany Waldisperg ◽  
Felipe I. Torres ◽  
Sergio A. Carrasco ◽  
Javier Sellanes ◽  
...  
Keyword(s):  
Body Size ◽  
Species Composition ◽  
Size Structure ◽  
Environmental Gradients ◽  
Ecological Factors ◽  
Taxonomic Composition ◽  
Latitudinal Gradients ◽  
Size Segregation ◽  
Biogeographic Patterns ◽  
Diversity Gradient

Abstract Intertidal communities’ composition and diversity usually exhibit strong changes in relation to environmental gradients at different biogeographical scales. This study represents the first comprehensive diversity and composition description of polyplacophoran assemblages along the Peruvian Province (SE Pacific, 12°S–39°S), as a model system for ecological latitudinal gradients. A total of 4,775 chitons from 21 species were collected on twelve localities along the Peruvian Province. This sampling allowed us to quantitatively estimate the relative abundance of the species in this assemblage, and to test whether chitons conform to elementary predictions of major biogeographic patterns such as a latitudinal diversity gradient. We found that the species composition supported the division of the province into three ecoregional faunal groups (i.e. Humboldtian, Central Chile, and Araucanian). Though chiton diversity did not follow a clear latitudinal gradient, changes in species composition were dominated by smaller scale variability in salinity and temperature. Body size significantly differed by ecoregions and species, indicating latitudinal size-structure assamblages. In some localities body size ratios differed from a random assemblage, evidencing competition at local scale. Changes in composition between ecoregions influence body size structure, and their overlapping produce vertical size segregation, suggesting that competition coupled with environmental conditions structure these assemblages.

scholarly journals On the inconsistency of pollinator species traits for predicting either response to agricultural intensification or functional contribution

2016 ◽  
Author(s):  
Ignasi Bartomeus ◽  
Daniel P. Cariveau ◽  
Tina Harrison ◽  
Rachael Winfree
Keyword(s):  
Ecosystem Function ◽  
Agricultural Intensification ◽  
Biodiversity Loss ◽  
Species Traits ◽  
Crop Pollination ◽  
Wild Bees ◽  
Ecological Processes ◽  
Pollination Services ◽  
Species Response ◽  
Pollination Systems

AbstractThe response and effect trait framework, if supported empirically, would provide for powerful and general predictions about how biodiversity loss will lead to loss in ecosystem function. This framework proposes that species traits will explain how different species respond to disturbance (i.e. response traits) as well as their contribution to ecosystem function (i.e. effect traits). However, predictive response and effect traits remain elusive for most systems. Here, we present detailed data on crop pollination services provided by native, wild bees to explore the role of six commonly used species traits in determining how crop pollination is affected by increasing agricultural intensification. Analyses were conducted in parallel for three crop systems (watermelon, cranberry, and blueberry) located within the same geographical region (mid-Atlantic USA). Bee species traits did not strongly predict species’ response to agricultural intensification, and the few traits that were weakly predictive were not consistent across crops. Similarly, no trait predicted species’ overall functional contribution in any of the three crop systems, although body size was a good predictor of per capita efficiency in two systems. So far, most studies looking for response or effect traits in pollination systems have found weak and often contradicting links. Overall we were unable to make generalizable predictions regarding species responses to land-use change and its effect on the delivery of ecosystem services. Pollinator traits may be useful for understanding ecological processes in some systems, but thus far the promise of traits-based ecology has yet to be fulfilled for pollination ecology.

scholarly journals Niche conservatism drives the elevational diversity gradient in major groups of free-living soil unicellular eukaryotes

2020 ◽  
Author(s):  
Leonardo D. Fernández ◽  
Christophe V. W. Seppey ◽  
David Singer ◽  
Bertrand Fournier ◽  
Dylan Tatti ◽  
...  
Keyword(s):  
Spatial Scales ◽  
Elevational Gradient ◽  
Testate Amoebae ◽  
Latitudinal Gradients ◽  
Niche Conservatism ◽  
Energy Effect ◽  
Elevation Gradients ◽  
Diversity Gradient ◽  
Phylogenetic Overdispersion ◽  
Multicellular Organisms

Abstract Ancestral adaptations to warm and humid climates drive the biogeographical and macroecological patterns of numerous multicellular organisms. Recent evidence suggests that this niche conservatism may also be shaping broad-scale diversity patterns of soil unicellular organisms, although empirical evidence is limited to Acidobacteria and testate amoebae. Herein, we tested the predictions of this hypothesis for five major soil protist groups (Bacillariophyta, Cercomonadida, Ciliophora, Euglyphida and Kinetoplastida), separately, as well as combined, along an elevational gradient in Switzerland. We found support for the predictions of this hypothesis in all protist groups, including decreasing diversity and increasing geographical ranges towards high and cold elevations (Rapoport effect); correlations between diversity and temperature (species-energy effect); and communities phylogenetically structured by competition (phylogenetic overdispersion) at warm-humid sites and habitat filtering (phylogenetic clustering) at cold-humid sites. Mid-domain null models confirmed that these findings were not the result of stochastic processes. Our results therefore suggest that soil protists exhibit evolutionary constraints to warm and humid climates, probably linked to an ancestral adaptation to (sub)tropical-like environments, which limits their survival in exceedingly cold sites. This niche conservatism possibly drives their biogeographical and macroecological patterns both at the local (e.g., temperature, humidity gradients along elevation gradients) and more global (e.g., latitudinal gradients) spatial scales.

scholarly journals No latitudinal gradients in tempo or mode of morphological evolution in birds

2020 ◽  
Author(s):  
J. Drury ◽  
J. Clavel ◽  
J.A. Tobias ◽  
J. Rolland ◽  
C. Sheard ◽  
...  
Keyword(s):  
Species Interactions ◽  
Morphological Evolution ◽  
Latitudinal Gradients ◽  
Phenotypic Evolution ◽  
Trait Evolution ◽  
Trait Divergence ◽  
Diversity Gradient ◽  
The Tropics ◽  
The Impact ◽  
Phylogenetic Models

AbstractThe latitudinal diversity gradient is one of the most striking patterns in nature yet its implications for morphological evolution are poorly understood. In particular, it has been proposed that an increased intensity of species interactions in tropical biota may either promote or constrain trait evolution, but which of these outcomes predominates remains uncertain. Here, we develop tools for fitting phylogenetic models of phenotypic evolution in which the impact of species interactions can vary across lineages. Deploying these models on a global avian trait dataset to explore differences in trait divergence between tropical and temperate lineages, we find that the effect of latitude on the mode and tempo of morphological evolution is weak and clade- or trait-dependent. Our results indicate that species interactions do not disproportionately impact morphological evolution in tropical bird families and question the validity and universality of previously reported patterns of slower trait evolution in the tropics.

scholarly journals Floral herbivory does not reduce pollination-mediated fitness in shelter rewarding Royal Irises

2017 ◽  
Author(s):  
Mahua Ghara ◽  
Christina Ewerhardy ◽  
Gil Yardeni ◽  
Mor Matzliach ◽  
Yuval Sapir
Keyword(s):  
Fruit Set ◽  
Seed Set ◽  
Pollen Grains ◽  
Reproductive Organs ◽  
Pollen Grain ◽  
Lower Number ◽  
Pollen Deposition ◽  
Pollination Services ◽  
Pollinator Visitation ◽  
Direct Damage

ABSTRACTFlorivory, the damage to flowers by herbivores can affect fitness both directly and indirectly. Flowers consumed by florivores may fail to produce fruit or produce lower seed set because of direct damage to reproductive organs. In addition, eaten flowers are less attractive to pollinators because of reduced or modified advertisement, which reduces pollination services. While observational data are abundant, experimental evidence is scarce and results are contrasting. We tested experimentally the effect of florivory on both pollinator visitation and reproductive success in three species of the Royal Irises, which have large flowers that are attractive to pollinators, and potentially also for florivores. We hypothesized that florivory will reduce pollen deposition due to reduced attractiveness to pollinators, while fruit set and seed set will depend on the extent of florivory. We performed artificial florivory in two experiments over two years. In the first experiment, each of the three floral units of a single Iris flower was subject to either low or high artificial florivory, or left un-touched as control. We counted the number of pollen grains deposited on each of the three stigmas as a measure of pollinator visitation. In the second experiment, three flowers of the same plant received low, high, or no artificial florivory and were further recorded for fruit and seed production. In 2016, high artificial florivory revealed lower number of pollen grains on stigmas of Iris atropurpurea, but in 2017 there was no difference. Similarly, number of pollen grains in high artificial was lower than low florivory in 2017 in I. petrana. No significant effect of florivory was found on pollen grain deposition, fruit set or seed set. The results remained consistent across species and across years. The results undermine the assumption that flower herbivory is necessarily antagonistic interaction and suggests that florivores may not be strong selection agents on floral reproductive biology in the Oncocyclus irises.

scholarly journals Status and conservation of avian fauna of Sultanpur National Park Gurgaon, Haryana (India)

2012 ◽  
Vol 4 (2) ◽  
pp. 207-213 ◽  
Author(s):  
Girish Chopra ◽  
Anil K. Tyor ◽  
Seema Kumari ◽  
Deepak Rai
Keyword(s):  
Threatened Species ◽  
National Park ◽  
Bird Species ◽  
Avian Diversity ◽  
Migratory Species ◽  
Resident Species ◽  
Cattle Egret ◽  
Bubulcus Ibis ◽  
Order Passeriformes

The present study was conducted in Sultanpur National Park Gurgaon, Haryana (India) from February, 2011 to January, 2012 to analyze the avian diversity along with its status and abundance. During the study period, a total of 113 species of birds belonging to 14 orders, 35 families and 80 genera were identified. Maximum 41 species belonging to 12 families of order Passeriformes represented 36.28% of the total identified avian fauna while Podicipediformes and Strigiformes were the least represented avian orders (0.88%) with one species each,namely, Little Grebe, Tachybaptus ruficollis and Spotted Owlet, Athene brama respectively. Out of total reported 113 species, 64 were ‘resident’ species and 49 were ‘migrant’ species. Most of the migratory species were winter visitors except Red throated flycatcher, Ficedula parva; Orange Headed Thrush, Zoothera citrine and Eurasian Golden Oriole, Oriolus oriolus which were summer visitors. In all, 42 species were ‘common’, 33 species were ‘uncommon’ and 38 species were ‘occasional’ bird species. Based on sighting, White Breasted Kingfisher, Halcyonsmyrnensis; White Breasted Water Hen, Amaurornis phoenicurus; Common Moorhen, Gallinule chloropus; Black Wing Stilt, Himantopus himantopus; Red Wattled lapwing, Vanellus indicus; Cattle Egret, Bubulcus ibis and Indian Pond Heron, Ardeola grayii were common wetland bird species of Sultanpur National Park while Pied king fisher, Ceryle rudis and Coppersmith Barbet, Megalaima haemacephala were ‘rarely sighted’ bird species. During the study period, 7 ‘globally threatened’ species, namely, Painted Stork, Mycteria leucocephala; Black neck Stork, Ephippiorhynchus asiaticus; Black headed Ibis, Threskiornis melanocephalus; Darter, Anhinga melanogaster; Pacific Reef Egret, Egretta sacra; Sarus Crane, Grus antigone alongwith Hogson bushchat, Saxicola insignis were also recorded from the study area.

scholarly journals Diversity of resident plant communities could weaken their allelopathic resistance against alien and native invaders

2021 ◽  
Author(s):  
Ling Yuan ◽  
Junmin Li ◽  
Mark van Kleunen
Keyword(s):  
Plant Communities ◽  
Single Species ◽  
Resident Species ◽  
Test Species ◽  
Diverse Communities ◽  
Allelopathic Effects ◽  
Almost All ◽  
Germination Experiment ◽  
Germinated Seeds

AbstractElton’s classic diversity-invasibility hypothesis posits that diversity of resident communities increases resistance against invaders. We tested whether the diversity-invasibility relationsip might be mediated by allelopathic effects of the resident species. In a large germination experiment, we exposed seeds of six alien and six native test species to leachates of one, three, six or twelve species. The leachates tended to slightly delay germination, and almost all single-species leachates reduced the proportion of germinated seeds. Nevertheless, the overall effect of the plant leachate mixtures on the proportion of germinated seeds was not significant. This was because a higher diversity of the leachates increased the proportion of germinated seeds, particularly for native test species. Among the six alien test species, it was only the most invasive one that benefited from increased diversity of the leachates, just like the natives did. Overall, our findings suggest that allelopathy of diverse communities does not provide resistance but could actually facilitate the germination of invaders.

scholarly journals Potential habitat suitability of Iraqi amphibians under climate change

2020 ◽  
Vol 21 (2) ◽  
Author(s):  
Emad Kaky
Keyword(s):  
Climate Change ◽  
Conservation Planning ◽  
Habitat Suitability ◽  
Niche Overlap ◽  
Biodiversity Loss ◽  
Potential Habitat ◽  
Conservation Actions ◽  
Rcp 8.5 ◽  
Threaten Species

Abstract. Kaky E. 2020. Potential habitat suitability of Iraqi amphibians under climate change. Biodiversitas 21: 731-742. Biodiversity management and conservation planning are two techniques for reducing the rate of biodiversity loss, especially under the effect of climate change. Here 289 records of five species of amphibians from Iraq and seven environmental variables were used with MaxEnt to predict potential habitat suitability for each species under current and future conditions, using the 5th IPCC assessment  (RCP 2.6 and RCP 8.5 for the year 2050). The models suggest that annual precipitation and the mean temperature of the wettest quarter are the main factors that shape the distributions of these species. The estimated current habitat suitability was closely similar to that for 2050 under both scenarios, with a high niche overlap between them for all species. Among species, there were low niche overlaps between the frogs Bufo viridis, Hyla savignyi and Rana ridibunda, and also between the salamanders Neurergus crocatus and Neurergus microspilotus. Future sampling should focus on areas not currently covered by records to reduce bias. The results are a vital first step in long-term conservation planning for these species. Via sharing these results with decision-makers and stakeholders a crucial conservation actions need to increase Iraqi Protected Areas to avoid losing biodiversity in Iraq especially the unique populations and threaten species.

Sign in / Sign up

Export Citation Format

Share Document