Publications by authors named "Pablo L Peri"

19 Publications

  • Page 1 of 1

General destabilizing effects of eutrophication on grassland productivity at multiple spatial scales.

Nat Commun 2020 10 23;11(1):5375. Epub 2020 Oct 23.

Department of Ecology, Evolution, and Behavior, University of MN, St. Paul, MN, 55108, USA.

Eutrophication is a widespread environmental change that usually reduces the stabilizing effect of plant diversity on productivity in local communities. Whether this effect is scale dependent remains to be elucidated. Here, we determine the relationship between plant diversity and temporal stability of productivity for 243 plant communities from 42 grasslands across the globe and quantify the effect of chronic fertilization on these relationships. Unfertilized local communities with more plant species exhibit greater asynchronous dynamics among species in response to natural environmental fluctuations, resulting in greater local stability (alpha stability). Moreover, neighborhood communities that have greater spatial variation in plant species composition within sites (higher beta diversity) have greater spatial asynchrony of productivity among communities, resulting in greater stability at the larger scale (gamma stability). Importantly, fertilization consistently weakens the contribution of plant diversity to both of these stabilizing mechanisms, thus diminishing the positive effect of biodiversity on stability at differing spatial scales. Our findings suggest that preserving grassland functional stability requires conservation of plant diversity within and among ecological communities.
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http://dx.doi.org/10.1038/s41467-020-19252-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7585434PMC
October 2020

Microbial processing of plant remains is co-limited by multiple nutrients in global grasslands.

Glob Chang Biol 2020 08 10;26(8):4572-4582. Epub 2020 Jun 10.

German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany.

Microbial processing of aggregate-unprotected organic matter inputs is key for soil fertility, long-term ecosystem carbon and nutrient sequestration and sustainable agriculture. We investigated the effects of adding multiple nutrients (nitrogen, phosphorus and potassium plus nine essential macro- and micro-nutrients) on decomposition and biochemical transformation of standard plant materials buried in 21 grasslands from four continents. Addition of multiple nutrients weakly but consistently increased decomposition and biochemical transformation of plant remains during the peak-season, concurrent with changes in microbial exoenzymatic activity. Higher mean annual precipitation and lower mean annual temperature were the main climatic drivers of higher decomposition rates, while biochemical transformation of plant remains was negatively related to temperature of the wettest quarter. Nutrients enhanced decomposition most at cool, high rainfall sites, indicating that in a warmer and drier future fertilized grassland soils will have an even more limited potential for microbial processing of plant remains.
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http://dx.doi.org/10.1111/gcb.15146DOI Listing
August 2020

Nutrient availability controls the impact of mammalian herbivores on soil carbon and nitrogen pools in grasslands.

Glob Chang Biol 2020 Feb 3. Epub 2020 Feb 3.

Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, The Netherlands.

Grasslands are subject to considerable alteration due to human activities globally, including widespread changes in populations and composition of large mammalian herbivores and elevated supply of nutrients. Grassland soils remain important reservoirs of carbon (C) and nitrogen (N). Herbivores may affect both C and N pools and these changes likely interact with increases in soil nutrient availability. Given the scale of grassland soil fluxes, such changes can have striking consequences for atmospheric C concentrations and the climate. Here, we use the Nutrient Network experiment to examine the responses of soil C and N pools to mammalian herbivore exclusion across 22 grasslands, under ambient and elevated nutrient availabilities (fertilized with NPK + micronutrients). We show that the impact of herbivore exclusion on soil C and N pools depends on fertilization. Under ambient nutrient conditions, we observed no effect of herbivore exclusion, but under elevated nutrient supply, pools are smaller upon herbivore exclusion. The highest mean soil C and N pools were found in grazed and fertilized plots. The decrease in soil C and N upon herbivore exclusion in combination with fertilization correlated with a decrease in aboveground plant biomass and microbial activity, indicating a reduced storage of organic matter and microbial residues as soil C and N. The response of soil C and N pools to herbivore exclusion was contingent on temperature - herbivores likely cause losses of C and N in colder sites and increases in warmer sites. Additionally, grasslands that contain mammalian herbivores have the potential to sequester more N under increased temperature variability and nutrient enrichment than ungrazed grasslands. Our study highlights the importance of conserving mammalian herbivore populations in grasslands worldwide. We need to incorporate local-scale herbivory, and its interaction with nutrient enrichment and climate, within global-scale models to better predict land-atmosphere interactions under future climate change.
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http://dx.doi.org/10.1111/gcb.15023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7155038PMC
February 2020

Essential Nutrient and Trace Element Foliar Resorption of Two Co-Existing Species Grown Under Different Environmental Conditions in Southern Patagonia.

Front Plant Sci 2019 27;10:1542. Epub 2019 Nov 27.

Department of Forestry Research, Instituto Nacional de Tecnología Agropecuaria (INTA), Santa Cruz, Argentina.

Nutrient resorption is crucial for mineral element conservation and efficiency of forest species, but knowledge on its significance and the mechanisms involved is still limited for most species and habitats. Focusing on the harsh conditions for plant growth and survival of southern Patagonia, a field study for comparing the rate of foliar resorption of macro-, micro-nutrients, and trace elements in coexisting and forests was performed. Forests located in three contrasting productivity sites (with different soil and climatic conditions) were selected, and mature, functional versus senescent leaves of both species were collected at two different dates of the growing season. Macro- (N, P, Ca, K, S, and Mg), micronutrients (B, Cu, Fe, Mn, Zn, and Ni), and trace elements (Al, Li, Pb, Rb, Sr, Ti, and Tl) were determined in foliar tissues. The mineral element concentrations of mature and senescent leaves were used for calculating the nutrient resorption efficiency (NuR). In general, and making an average of all sites and species, macro-nutrient resorption showed a decreasing trend for N > S = K > P > Mg, being Ca the only macro-nutrient with negative values (i.e., no resorption). Resorption of the majority of the elements did not vary between species in any of the evaluated sites. Variation across sites in nutrient resorption efficiency for most macronutrients, some micronutrients, and trace elements was observed for , whereas had a similar NuR for all experimental sites. On the other hand, regardless of the site or the species, some elements were not resorbed (e.g., B, Cu, Fe, Mn, Al, and Ti). It is concluded that both species performed similarly concerning their nutrient conservation strategy, when coexisting in the same mixed forest. However, no evidence was gained for an increased rate of foliar NuR in association with the sites subjected to more limiting soil and climatic conditions for plant growth.
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http://dx.doi.org/10.3389/fpls.2019.01542DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6890610PMC
November 2019

Soils need to be considered when assessing the impacts of land-use change on carbon sequestration.

Nat Ecol Evol 2019 12 4;3(12):1642. Epub 2019 Nov 4.

Escuela de Agroforestería, Universidad Científica del Sur, Lima, Peru.

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http://dx.doi.org/10.1038/s41559-019-1026-8DOI Listing
December 2019

Land sharing in South Patagonia: Conservation of above-ground beetle diversity in forests and non-forest ecosystems.

Sci Total Environ 2019 Nov 1;690:132-139. Epub 2019 Jul 1.

Laboratorio de Recursos Agroforestales (CADIC-CONICET), Houssay 200, 9410 Ushuaia, Tierra del Fuego, Argentina. Electronic address:

Land-sharing strategies, as variable retention silvicultural proposals, are useful to mitigate harmful effects of economic activities on forest biodiversity; benefits have been reported worldwide for several organisms. However, we suggest that this approach could be useful to improve beetle conservation not only in forests but also in other ecosystem types, based on the results from Southern Patagonia (Argentina). We studied above-ground beetle communities using pitfall traps in Nothofagus pumilio forests, Mulguraea tridens shrublands, and magellanic steppes. The forests were located in Tierra del Fuego Province, while the shrublands and the steppes were in Santa Cruz Province. In forests and shrublands, we compared retention approaches (aggregated/dispersed retention harvesting in forests, and managed cut and retention strips in shrublands) vs. control situations (without harvesting/cuttings). In dry and humid steppes, both impacted by livestock, we evaluated grazed and exclusion paddocks, comparable to structural retentions (reference areas without grazing do not exist). Richness, abundance, frequency, Shannon-Wiener diversity and Pielou evenness indices, and similarity among assemblages were evaluated using univariate and multivariate statistical tests. In forests and shrublands, retention approaches (aggregated/dispersed and strips) allowed the partial or total maintenance of beetle community richness, preserving them similar to natural and non-impacted ecosystems. In dry and humid steppes, exclusion areas presented significantly different richness, abundance and diversity of arthropod assemblages, but with inverse trends: lower values in grazed areas than in exclusions in dry steppe, and higher values in grazed areas than in exclusions in humid steppe. We concluded that land-sharing could be implemented in forests and non-forest ecosystems to preserve beetle communities, being the variable retention approaches and the grazing exclusion areas good alternatives for private or public lands. Likewise, we consider that legislation to promote conservation (like National Law 26331) should not be only applicable for and implemented in forests, but also in non-forest ecosystems.
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http://dx.doi.org/10.1016/j.scitotenv.2019.06.517DOI Listing
November 2019

Potential biodiversity map of understory plants for Nothofagus forests in Southern Patagonia: Analyses of landscape, ecological niche and conservation values.

Sci Total Environ 2019 Sep 16;682:301-309. Epub 2019 May 16.

Laboratorio de Recursos Agroforestales, Centro Austral de Investigaciones Científicas (CADIC), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Houssay 200, 9410 Ushuaia, Tierra del Fuego, Argentina. Electronic address:

The role of understory plants in native forests is critical for ecosystem function, wildlife protection and ecosystem productivity. The interest to estimate biodiversity increased during the last decades at landscape level. The objective was to elaborate a map of potential biodiversity (MPB) of understory species of Nothofagus forest using potential habitat suitability maps (PHS) of 15 plants in Santa Cruz province, Argentina. Additionally, we asked the following questions: (i) Were plant species differentially distributed according to the forest types?, (ii) do forest types represent different plant species assemblage with specific ecological niche requirements?, and (iii) is it possible to detect hotspots in the MBP according to the forest types? We used 721 plots database of vascular plants, from where 15 indicator species were identified. The assemblage species for different forests (Nothofagus antarctica, N. pumilio and evergreen mixed) were analysed using a detrended correspondence analysis. Also, we explored 41 potential explanatory variables to develop PHS, and combined these maps to obtain one MPB (1-100%). Finally, we analysed the outputs into a GIS through different landscapes alternatives to detect hotspot areas. Marginality and specialization values allowed identifying species assemblage that presented similar variability in the habitat requirements. MPB varied across the landscape, with higher values in the south and lower values near glaciers. MPB had the highest values in N. antarctica forest with >50% cover at landscape level. N. antarctica present more hotspots than N. pumilio forests, mainly in the south, compared to mixed evergreen forests which present few hotspots near glaciers. These results can be used as a tool to design new management and conservation strategies at landscape level.
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http://dx.doi.org/10.1016/j.scitotenv.2019.05.179DOI Listing
September 2019

Soil carbon is a useful surrogate for conservation planning in developing nations.

Sci Rep 2019 03 7;9(1):3905. Epub 2019 Mar 7.

School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, 2052, Australia.

Defining the optimal placement of areas for biodiversity conservation in developing nations remains a significant challenge. Our best methods for spatially targeting potential locations for biodiversity conservation rely heavily on extensive georeferenced species observation data which is often incomplete or lacking in developing nations. One possible solution is the use of surrogates that enable site assessments of potential biodiversity values which use either indicator taxa or abiotic variables, or both. Among the plethora of abiotic variables, soil carbon has previously been identified as a potentially powerful predictor for threatened biodiversity, but this has not yet been confirmed with direct observational data. Here we assess the potential value of soil carbon for spatial prediction of threatened species using direct measurements as well as a wide range of GIS derived abiotic values as surrogates for threatened plant species in the PEBANPA network of permanent plots in Southern Patagonia. We find that soil carbon significantly improves the performance of a biodiversity surrogate elaborated using abiotic variables to predict the presence of threatened species. Soil carbon could thus help to prioritize sites in conservation planning. Further, the results suggest that soil carbon on its own can be a much better surrogate than other abiotic variables when prioritization of sites for conservation are calibrated on increasingly small sets of observation plots. We call for the inclusion of soil carbon data in the elaboration of surrogates used to optimize conservation investments in the developing world.
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http://dx.doi.org/10.1038/s41598-019-40741-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6405948PMC
March 2019

Isotopic evidence for oligotrophication of terrestrial ecosystems.

Nat Ecol Evol 2018 11 22;2(11):1735-1744. Epub 2018 Oct 22.

Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China.

Human societies depend on an Earth system that operates within a constrained range of nutrient availability, yet the recent trajectory of terrestrial nitrogen (N) availability is uncertain. Examining patterns of foliar N concentrations and isotope ratios (δN) from more than 43,000 samples acquired over 37 years, here we show that foliar N concentration declined by 9% and foliar δN declined by 0.6-1.6‰. Examining patterns across different climate spaces, foliar δN declined across the entire range of mean annual temperature and mean annual precipitation tested. These results suggest declines in N supply relative to plant demand at the global scale. In all, there are now multiple lines of evidence of declining N availability in many unfertilized terrestrial ecosystems, including declines in δN of tree rings and leaves from herbarium samples over the past 75-150 years. These patterns are consistent with the proposed consequences of elevated atmospheric carbon dioxide and longer growing seasons. These declines will limit future terrestrial carbon uptake and increase nutritional stress for herbivores.
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http://dx.doi.org/10.1038/s41559-018-0694-0DOI Listing
November 2018

The database of the PREDICTS (Projecting Responses of Ecological Diversity In Changing Terrestrial Systems) project.

Ecol Evol 2017 01 16;7(1):145-188. Epub 2016 Dec 16.

Imperial College London South Kensington London UK.

The PREDICTS project-Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)-has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.
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http://dx.doi.org/10.1002/ece3.2579DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5215197PMC
January 2017

Positive biodiversity-productivity relationship predominant in global forests.

Science 2016 10;354(6309)

Wageningen University and Research (Alterra), Team Vegetation, Forest and Landscape Ecology-6700 AA, Netherlands.

The biodiversity-productivity relationship (BPR) is foundational to our understanding of the global extinction crisis and its impacts on ecosystem functioning. Understanding BPR is critical for the accurate valuation and effective conservation of biodiversity. Using ground-sourced data from 777,126 permanent plots, spanning 44 countries and most terrestrial biomes, we reveal a globally consistent positive concave-down BPR, showing that continued biodiversity loss would result in an accelerating decline in forest productivity worldwide. The value of biodiversity in maintaining commercial forest productivity alone-US$166 billion to 490 billion per year according to our estimation-is more than twice what it would cost to implement effective global conservation. This highlights the need for a worldwide reassessment of biodiversity values, forest management strategies, and conservation priorities.
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http://dx.doi.org/10.1126/science.aaf8957DOI Listing
October 2016

Comment on "Worldwide evidence of a unimodal relationship between productivity and plant species richness".

Science 2016 Jan;351(6272):457

Department of Ecology, Environment and Evolution, La Trobe University, Kingsbury Drive, Bundoora 3086, Victoria, Australia.

Fraser et al. (Reports, 17 July 2015, p. 302) report a unimodal relationship between productivity and species richness at regional and global scales, which they contrast with the results of Adler et al. (Reports, 23 September 2011, p. 1750). However, both data sets, when analyzed correctly, show clearly and consistently that productivity is a poor predictor of local species richness.
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http://dx.doi.org/10.1126/science.aad6236DOI Listing
January 2016

Effectiveness of fencing and hunting to control Lama guanicoe browsing damage: Implications for Nothofagus pumilio regeneration in harvested forests.

J Environ Manage 2016 Mar 17;168:165-74. Epub 2015 Dec 17.

Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Rivadavia 1917 (1033) Ciudad de Buenos Aires, Buenos Aires, Argentina; INTA EEA Santa Cruz, Mahatma Ghandi 1322 (9400) Río Gallegos, Santa Cruz, Argentina; Universidad Nacional de la Patagonia Austral (UNPA), Lisandro de la Torre 1070 (9400) Río Gallegos, Santa Cruz, Argentina.

Browsing damage by native ungulates is often to be considered one of the reasons of regeneration failure in Nothofagus pumilio silvicultural systems. Fencing and hunting in forests at regeneration phase have been proposed to mitigate browsing effects. This study aims to determine effectiveness of these control methods in harvested forests, evaluating browsing damage over regeneration, as well as climate-related constraints (freezing or desiccation). Forest structure and regeneration plots were established in two exclosures against native ungulates (Lama guanicoe) by wire fences in the Chilean portion of Tierra del Fuego island, where tree regeneration density, growth, abiotic damage and quality (multi-stems and base/stem deformation) were assessed. Exclosures did not influence regeneration density (at the initial stage with < 1.3 m high, and at the advanced stage with >1.3 m high). However, sapling height at 10-years old was significantly lower outside (40-50 cm high) than inside exclosures (80-100 cm), and also increased their annual height growth, probably as a hunting effect. Likewise, quality was better inside exclosures. Alongside browsing, abiotic conditions negatively influenced sapling quality in the regeneration phase (20%-28% of all seedlings), but greatly to taller plants (as those from inside exclosure). This highlights the importance of considering climatic factors when analysing browsing effects. For best results, control of guanaco in recently harvested areas by fencing should be applied in combination with a reduction of guanaco density through continuous hunting. The benefits of mitigation actions (fencing and hunting) on regeneration growth may shorten the regeneration phase period in shelterwood cutting forests (30-50% less time), but incremental costs must be analysed in the framework of management planning by means of long-term studies.
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http://dx.doi.org/10.1016/j.jenvman.2015.11.051DOI Listing
March 2016

Convergence of soil nitrogen isotopes across global climate gradients.

Sci Rep 2015 Feb 6;5:8280. Epub 2015 Feb 6.

Biogéochimie des Ecosystèmes Forestiers, INRA Nancy, Champenoux, 54280, France.

Quantifying global patterns of terrestrial nitrogen (N) cycling is central to predicting future patterns of primary productivity, carbon sequestration, nutrient fluxes to aquatic systems, and climate forcing. With limited direct measures of soil N cycling at the global scale, syntheses of the (15)N:(14)N ratio of soil organic matter across climate gradients provide key insights into understanding global patterns of N cycling. In synthesizing data from over 6000 soil samples, we show strong global relationships among soil N isotopes, mean annual temperature (MAT), mean annual precipitation (MAP), and the concentrations of organic carbon and clay in soil. In both hot ecosystems and dry ecosystems, soil organic matter was more enriched in (15)N than in corresponding cold ecosystems or wet ecosystems. Below a MAT of 9.8°C, soil δ(15)N was invariant with MAT. At the global scale, soil organic C concentrations also declined with increasing MAT and decreasing MAP. After standardizing for variation among mineral soils in soil C and clay concentrations, soil δ(15)N showed no consistent trends across global climate and latitudinal gradients. Our analyses could place new constraints on interpretations of patterns of ecosystem N cycling and global budgets of gaseous N loss.
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http://dx.doi.org/10.1038/srep08280DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4319163PMC
February 2015

Correlations between physical and chemical defences in plants: tradeoffs, syndromes, or just many different ways to skin a herbivorous cat?

New Phytol 2013 Apr 14;198(1):252-263. Epub 2013 Jan 14.

Lab. Ecotono, CRUB-UNC, INIBIOMA-CONICET, 8400, Bariloche, Argentina.

Most plant species have a range of traits that deter herbivores. However, understanding of how different defences are related to one another is surprisingly weak. Many authors argue that defence traits trade off against one another, while others argue that they form coordinated defence syndromes. We collected a dataset of unprecedented taxonomic and geographic scope (261 species spanning 80 families, from 75 sites across the globe) to investigate relationships among four chemical and six physical defences. Five of the 45 pairwise correlations between defence traits were significant and three of these were tradeoffs. The relationship between species' overall chemical and physical defence levels was marginally nonsignificant (P = 0.08), and remained nonsignificant after accounting for phylogeny, growth form and abundance. Neither categorical principal component analysis (PCA) nor hierarchical cluster analysis supported the idea that species displayed defence syndromes. Our results do not support arguments for tradeoffs or for coordinated defence syndromes. Rather, plants display a range of combinations of defence traits. We suggest this lack of consistent defence syndromes may be adaptive, resulting from selective pressure to deploy a different combination of defences to coexisting species.
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http://dx.doi.org/10.1111/nph.12116DOI Listing
April 2013

Putting plant resistance traits on the map: a test of the idea that plants are better defended at lower latitudes.

New Phytol 2011 Aug 3;191(3):777-788. Epub 2011 May 3.

Facultad de Ciencias Forestales, University of Nuevo Leon, Linares 67700, Mexico.

• It has long been believed that plant species from the tropics have higher levels of traits associated with resistance to herbivores than do species from higher latitudes. A meta-analysis recently showed that the published literature does not support this theory. However, the idea has never been tested using data gathered with consistent methods from a wide range of latitudes. • We quantified the relationship between latitude and a broad range of chemical and physical traits across 301 species from 75 sites world-wide. • Six putative resistance traits, including tannins, the concentration of lipids (an indicator of oils, waxes and resins), and leaf toughness were greater in high-latitude species. Six traits, including cyanide production and the presence of spines, were unrelated to latitude. Only ash content (an indicator of inorganic substances such as calcium oxalates and phytoliths) and the properties of species with delayed greening were higher in the tropics. • Our results do not support the hypothesis that tropical plants have higher levels of resistance traits than do plants from higher latitudes. If anything, plants have higher resistance toward the poles. The greater resistance traits of high-latitude species might be explained by the greater cost of losing a given amount of leaf tissue in low-productivity environments.
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http://dx.doi.org/10.1111/j.1469-8137.2011.03732.xDOI Listing
August 2011

A new species of Aphis L (Hemiptera: Aphididae) from South Patagonia.

Neotrop Entomol 2009 May-Jun;38(3):366-9

Cátedra de Entomología, Facultad de C.E.F. y N., University Nacional de Córdoba, Córdoba, Argentina.

Aphis adesmiae Delfino sp. n. is described from South Patagonia (Argentina). This new aphid species is associated with a native shrub Adesmia boronioides (Fabaceae). Morphological characters of the apterous viviparous female are described and illustrated and biological remarks are given.
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http://dx.doi.org/10.1590/s1519-566x2009000300011DOI Listing
September 2009