Centro de Ecologia Funcional/Centre for Functional Ecology

Helena Freitas

Phone: +351 239 855236
e-mail: hfreitas@ci.uc.pt
Category: Full Professor
Department: Life Sciences
Research Line: Biodiversity and Ecosystems Functioning
Direct URL for this page: http://cfe.uc.pt/hfreitas

Research Interests

Main field: Plant Ecology. Major research areas: 1. Ecosystem physiology; 2. Ecology of invasive and exotic species; 3. Ecology and taxonomy of micorrhizal fungi; 4. Plant-soil interactions; 5. Physiology and biochemistry of heavy metals tolerance; 6. Scenarios of land use change and management. Other interests: Nature conservation. Microbial ecology.

Academic Achievements

1993 - PhD in Plant Ecology, University of Coimbra, Portugal

1994/1995 - Pos-Doc in Ecology (Mediterranean Ecosystems) Stanford University - Stanford, USA

2000 - “Agregação” in Botany

University duties

Director of the Botanical Garden of the University of Coimbra

Coordinator of CEF

Others

President of the Portuguese Ecological Society (SPECO)

Vice-President of the Board of the European Ecological Federation

Projects in Progress (4)
Projects Concluded (3)

International Network of universities and institutes for raising awareness on dual-use concerns in bio-technology (see details)

Value MicotecTruf – Value Mycology-Technology-Truficulture (see details)

F-ECO-DL – Fruit ECO-Drying Line (see details)

Evolutionary changes to reproductive systems during the invasion process of the polyploid Oxalis pes-caprae (see details)

MUTUALNET. Below and aboveground mutualisms and the invasion by Australian acacias: relevance on invasive dynamics and consequences for native ecosystems. (see details)

As missões botânicas em África – nos trilhos de um naturalista (see details)

RESCOE - Risk Assessment And Ecological Sustainability of Cork Oak in Montado Ecosystems (see details)

ISI Papers
Other Papers
Books
Books Chapters
Thesis
Communications
Other publications

Ma Y, Rajkumar M, Vicente J, Freitas H. (in press) Inoculation of Ni-resistant plant growth promoting bacterium Psychrobacter sp. strain SRS8 for the improvement of nickel phytoextraction by energy crops.. International Journal of Phytoremediation . (see details)

Marchante, H., Freitas, H. & Hoffmann, J.H. , Marchante, H., Freitas, H., Hoffmann, J.H. (in press) The potential role of seed banks in the recovery of dune ecosystems after removal of invasive plant species. Applied Vegetation Science. (see details)

Barrico L., Azul A.M., Morais M.C., Coutinho A.P., Freitas H., Castro P. (in press) Biodiversity in urban ecosystems: Plants and macromycetes as indicators for conservation planning in the city of Coimbra (Portugal). Landscape and Urban Planning. (see details)

M. Rajkumar., S. Sandhya., M.N.V. Prasad, H. Freitas (in press) Perspectives of plant associated microbes in heavy metal phytoremediation. Biotechnology advances. (see details)

Mesquita N., Portugal A., Piñar G., Loureiro J., Coutinho A.P., Trovão J., Nunes I., Botelho L.M., Freitas H. (in press) Flow cytometry as a tool to assess the effects of gamma radiation on the viability, growth and metabolic activity of fungal spores. (see details)

CRISÓSTOMO, J.A., RODRÍGUEZ-ECHEVERRÍA, S., FREITAS, H. (2013) Co-introduction of exotic rhizobia to the rhizosphere of the invasive legume Acacia saligna along an intercontinental gradient.. Applied Soil Ecology. 64, 118-126. (see details)

Roiloa, S. R., Rodríguez-Echeverría, S., Freitas, H., Retuerto, R. (2013) Developmentally-programmed división of labour in the clonal invader Carpobrotus edulis. Biological Invasions. (see details)

E. Buscardo, S. Rodríguez-Echeverría, L. Barrico, M. García, H. Freitas, M P. Martín, P. Angelis, L. A.H. Muller (2012) Is the potential for the formation of common mycorrhizal networks influenced by fire frequency?. Soil Biology & Biochemistry. 46 , 136-144. (see details)

M.C. Morais, M.R. Panuccio, A. Muscolo, H. Freitas (2012) Salt tolerance traits increase the invasive success of Acacia longifolia in Portuguese coastal dunes. Plant Physiology and Biochemistry. 55, 60-65. (see details)

M.C. Morais,M. R. Panuccio, A. Muscolo, H. Freitas (2012) Does salt stress increase the ability of the exotic legume Acacia longifolia to compete with native legumes in sand dune ecosystems?. Environmental and Experimental Botany. 82, 74-79. (see details)

H. Marchante, H. Freitas and J.H. Hoffmann (2011) Assessing the suitability and safety of a well-known bud-galling wasp, Trichilogaster acaciaelongifoliae, for biological control of Acacia longifolia in Portugal. Biological Control. 56, 2, 193-201. (see details)
Link: http://dx.doi.org/10.1016/j.biocontrol.2010.11.001

Y. Ma, M.N.V. Prasad, M. Rajkumar, H. Freitas (2011) Plant growth promoting rhizobacteria and endophytes accelerate phytoremediation of metalliferous soils. Biotechnology Advances. (see details)
Link: doi:10.1016/j.biotechadv.2010.12.001

Nabais C., Labuto G., Gonçalves S.C., Buscardo E., Semensatto D., Nogueira A.R.A., Freitas H. (2011) Effect of root age on the allocation of metals, amino acids and sugars in different cell fractions of the perennial grass Paspalum notatum (bahiagrass). Plant Physiology and Biochemistry. 49, 1442-1447. (see details)
Link: http://dx.doi.org/10.1016/j.plaphy.2011.09.010

Marchante, H., Freitas, H. , Hoffmann, J. H (2011) Post-clearing recovery of coastal dunes invaded by Acacia longifolia: is duration of invasion relevant for management success?. Journal of Applied Ecology. 48, 1295–1304. (see details)

Gutiérrez E., Campelo F., Camarero J.J., Ribas M., Muntán E., Nabais C., Freitas H. (2011) Climate controls act at different scales on the seasonal pattern of Quercus ilex L. stem radial increments in NE Spain. Trees. 25, 4, 637-647. (see details)
Link: http://www.springerlink.com/index/10.1007/s00468-011-0540-3

Azul AM, Sousa JP, Agerer R, Martín MP & Freitas H (2010) Land use practices and ectomycorrhizal fungal communities from oak woodlands dominated by Quercus suber L. considering drought scenarios. Mycorrhiza. 20, 2, 73-88 . (see details)

Mirta Teichberg, Sophia E. Fox, Ylva S. Olsen, Ivan Valiela, Paulina Martinetto, Oscar Iribarne, Elizabetiyuriko Muto, Monica A. V. Petti, Tha S N. Corbisier, Martín Soto-Jiménez, Federico Páez-Osun, (2010) Eutrophication and macroalgal blooms in temperate and tropical coastal waters: nutrient enrichment experiments with Ulva spp. Global Change Biology. 16, 9, 2624–2637. (see details)
Link: doi: 10.1111/j.1365-2486.2009.02108.x

Roiloa, S.R., Rodríguez-Echeverría, S., de la Peña, E. & Freitas H. (2010) Physiological integration increases survival and growth of the clonal invader Capobrotus edulis. Biological Invasions. 12, 1815-1823. (see details)
Link: DOI 10.1007/s10530-009-9592-

Maltez-Mouro S, Maestre FT & Freitas H. (2010) Co-occurrence patterns and abiotic stress in sand -dune communities: their relationship varies with spatial scale and the stress estimator. Acta Oecologica. 36 , 1, 80-84. (see details)
Link: DOI 10.1007/s10530-009-9613-2

Maltez-Mouro S, Maestre FT & Freitas H. (2010) Weak effects of the exotic invasive Carpobrotus edulis on the structure and compostition of Portuguese sand -dune communitties. Biological Invasions. 12, 7, 2117-2130 . (see details)

M.N.V. Prasad, Helena Freitas, Stefan Fraenzle, Simone Wuenschmann, Bernd Markert (2010) Knowledge explosion in phytotechnologies for environmental solutions. Environmental Pollution. 158, 18-23. (see details)

Campelo F., Nabais C., Gutiérrez E., Freitas H., García-González I. (2010) Vessel features of Quercus ilex L. growing under Mediterranean climate have a better climatic signal than tree-ring width. Trees. 24, 463-470. (see details)
Link: http://www.springerlink.com/content/a60015n3182064r8/

LORENZO, P. , RODRÍGUEZ-ECHEVERRÍA, S., GONZÁLEZ, L., FREITAS, H. (2010) Effect of invasive Acacia dealbata Link on soil microorganisms as determined by PCR-DGGE.. Applied Soil Ecology. 44, 245-251. (see details)

Castro H., Lehsten V. , Lavorel S. , Freitas H. (2010) Functional Response Traits in Relation to Land Use Change in the Montado. Agriculture, Ecosystems and Environment. 137, 1, 183-191. (see details)
Link: doi:10.1016/j.agee.2010.02.002

Castro H., Fortunel C., Freitas H. (2010) Effects of land abandonment on plant litter decomposition in a Montado system: relation to litter chemistry and community functional parameters. Plant and Soil. 333, 1-2, 181-190. (see details)

Y. Ma, M.N.V. Prasad, M. Rajkumar & H. Freitas (2010) Plant growth promoting rhizobacteria and endophytes accelerate phytoremediation of metalliferous soils. Biotechnology Advances. (see details)
Link: http://dx.doi.org/10.1016/j.biotechadv.2010.12.001

Barrico M.L., Rodríguez-Echeverría S., Freitas H. (2010) Diversity of soil basidiomycete communities associated with Quercus suber L. in Portuguese montados. European Journal of Soil Biology. 46, 280-287. (see details)

M. Rajkumar., N. Ae., M.N.V. Prasad., H. Freitas (2010) Potential of siderophore-producing bacteria for improving heavy-metal phytoextraction. Trends in Biotechnology. 28, 3, 142-149. (see details)

Marchante, H., Freitas, H., Hoffmann, J.H. (2010) Marchante, H., Seed ecology of an invasive alien species, Acacia longifolia (Fabaceae), in Portuguese dune ecosystems. American Journal of Botany . 97, 1-11. (see details)

BUSCARDO, E., RODRIÍGUEZ-ECHEVERRIA, S., MARTIÍN, M., DE ANGELIS, P. PEREIRA, J.S., FREITAS, H. (2010) Impact of wildfire return interval on the ectomycorrhizal resistant propagules communities of a Mediterranean open forest. Fungal Biology. 114, 628- 636. (see details)

Reis, CS; Dos Santos, MCV; Marais, M, et al. (2010) First record of Helicotylenchus varicaudatus Yuen, 1964 (Nematoda: Hoplolaimidae) parasitizing Ammophila arenaria (L.) Link in Portuguese coastal sand dunes. PHYTOPATHOLOGIA MEDITERRANEA . 49 , 2, 212-226. (see details)

Y. Ma, M. Rajkumar, and H. Freitas (2009) Improvement of plant growth and nickel uptake by nickel resistant plant growth promoting bacteria. Journal of Hazardous Materials. 166, 1154-1161. (see details)

Araújo GCL, Lemos SG, Nabais C (2009) Nickel sorption capacity of ground xylem of Quercus ilex trees and effects of selected ligands present in the xylem sap. Journal Plant Physiology. 166, 270-277. (see details)

Y. Ma, M. Rajkumar and H. Freitas (2009) Inoculation of plant growth promotinng bacterium Achromobacter xylosoxidans strain Ax10 for the improvement of copper phytoextraction by Brassica juncea.. Journal of Environmental Management . 90, 831-837. (see details)

RODRÍGUEZ ECHEVERRÍA, S., DE LA PEÑA, E., MOENS, M., FREITAS H., VAN DER PUTTEN, W. H. (2009) Can root-feeders alter the composition of AMF communities? Experimental evidences from the dune grass Ammophila arenaria.. Basic and Applied Ecology. 10, 131-140. (see details)

Rodriguez-Echeverría, S., Crisóstomo, J.A., Nabais, C., Freitas, H. (2009) Belowground mutualists and the invasive ability of Acacia longifolia in coastal dunes of Portugal. Biological Invasions. 11, 3, 651-661. (see details)

Elizabete Marchante, Annelise Kjøller, Sten Struwe, Helena Freitas (2009) Soil recovery after removal of the N2-fixing invasive Acacia longifolia: consequences for ecosystem restoration. Biological Invasions. 11, 813-823. (see details)
Link: DOI 10.1007/s10530-008-9295-1

Claire Fortunel et al. (2009) Leaf traits capture the effects of land use changes and climate on litter decomposability of herbaceous communities across Europe. Ecology. 90, 3, 598-611. (see details)

Gouveia, A.C., Freitas, H. (2009) Modulation of leaf attributes and water use efficiency in Quercus suber along a rainfall gradient. Trees. 23, 2, 267-275. (see details)
Link: http://dx.doi.org/10.1007/s00468-008-0274-z

Gonçalves S.C., Martins-Loução M.A. & Freitas H. (2009) Evidence of adaptive tolerance to nickel in isolates of Cenococcum geophilum from serpentine soils. Mycorrhiza. 19, 221-230. (see details)
Link: http://dx.doi.org/10.1007/s00572-008-0211-4

Rajkumar M, Prasad M.N.V, , Freitas H, Noriharu Ae (2009) Biotechnological Applications of Serpentine soil Bacteria for Phytoremediation of Trace metals`for publication in Critical Reviews in Biotechnology. Critical Reviews in Biotechnology. 29, 2, 120-130. (see details)

R. Jayakumar, M. Rajkumar, H. Freitas, N, Selvamurugan, S.V. Nair, T.Furuike, H. Tamura (2009) Preparation, charecterization, bioactive and metal uptake studies of alginate/phosphorilated chitin blend films. International Journal of Biological Macromolecules. 44, 107-111.. (see details)

Castro, H., Freitas, H. (2009) Aboveground biomass and productivity in the Montado: from herbaceous to shrub dominated communities. J.Arid Env.. 73, 506-511. (see details)

Myriam Kanoun-Boulé, Joaquim A.F. Vicente, Cristina Nabais, M.N.V. Prasad and Helena Freitas (2009) Ecophysiological tolerance of duckweeds exposed to copper. Aquatic Toxicology . 91, 1-9. (see details)
Link: doi:10.1016/j.aquatox.2008.09.009

Y. Ma, M. Rajkumar, H. Freitas (2009) Isolation and characterization of Ni mobilizing PGPB from serpentine soils and their potential in promoting plant growth and Ni accumulation by Brassica spp.. Chemosphere. 75, 719-725. (see details)

Maltez-Mouro S., García, L.V. & Freitas (2009) Maltez-Mouro S., García, L.V. & Freitas, H. Influence of forest structure and environmental variables on recruit survival and performance of two Mediterranean tree species (Quercus faginea L. and Q. suber Lam.).. European Journal of Forest Research. 128, 27-36. (see details)

R. Jayakuamr, M. Rajkumar, H. Freitas, P.T. Sudhees kumar, S.V. Nair, T. Faruike, H. Tamura. (2009) Bioactive and metal uptake studies of chitosan-graft-D-glucuronic acid membranes for tissue engineering and environmental applications.. International Journal of Biological Macromolecules . 45, 135-139. (see details)

Mesquita, N., Portugal, A., Videira, S., Rodríguez-Echeverría, S., Bandeira, A.M.L., Santos, M.J.A., Freitas, H. (2009) Fungal diversity in ancient documents. A case study on the Archive of the University of Coimbra. International Biodeterioration & Biodegradation. 63, 5, 626-629. (see details)
Link: doi:10.1016/j.ibiod.2009.03.010

M. Rajkumar., N. Ae., H. Freitas (2009) Endophytic bacteria and their potential to enhance heavy metal phytoextraction.. Chemosphere . 77, 153-160. (see details)

Campelo F., Nabais C., García-González I., Cherubini P., Gutiérrez E., Freitas H. (2009) Dendrochronology of Quercus ilex L. and its potential use for climate reconstruction in the Mediterranean region. Canadian Journal of Forest Research. 39 , 12, 2486-2493. (see details)
Link: http://rparticle.web-p.cisti.nrc.ca/rparticle/AbstractTemplateServlet?ca...

Azul AM, Castro P, Sousa JP, Freitas H (2009) Diversity and fruiting patterns of ectomycorrhizal and saprobic fungi as indicators of land use severity in managed woodlands dominated by Quercus suber L. - a case study from South Portugal. Canadian Journal of Forest Research. 39, 12, 2404-2417. (see details)

Castro, P., Valiela, I., Freitas, H. (2009) Sediment pool and plant content as indicators of nitrogen regimes in Portuguese estuaries. Journal of Experimental Marine Biology and Ecology. 380, 1-10. (see details)

Susana Rodriguez-Echeverria, W.H.Gera Hol, Helena Freitas, William Eason, Roger Cook. (2008) Arbuscular mycorrhizal fungi of Ammophila arenaria (L.) Link: Spore abundance and root colonisation in six locations of the European coast.. European Journal of Soil Biology. 44, 1, 30-36. (see details)
Link: doi:10.1016/j.ejsobi.2007.01.003

Rodríguez Echeverría, S., Freitas, H. and Van Der Putten, W.H. (2008) Genetic diversity and differentiation of Ammophila arenaria (L.) Link as revealed by ISSR markers. Journal of Coastal Research. 24, 1, 122-126. (see details)

Prasad M.N.V, Rajkumar M, Freitas H (2008) Rehabilitation of abandoned mine sites: connection to bioprospecting of metal tolerant plants and phytoassisted rhizoremediation.. The Paleobotanist . 57, 3, 559-571. (see details)

Azul AM, Ramos V, Pato A, Azenha M, Freitas H (2008) Mycorrhiza in the Mediterranean Basin: safety teaching and training. Journal of Biological Education. 42, 3, 54-61. (see details)
Link: http://www.iob.org/userfiles/File/JBE_42_3_Azul.pdf

Buscardo, E., Smith G.F., Kelly, D.L., Freitas, H., Iremonger, S., Mitchell F., O’Donoghue, S. and McKee, A.M. (2008) The early effects of afforestation on biodiversity of grasslands in Ireland. Biodiversity and Conservation. 17, 1057-1072. (see details)

Rajkumar, M., Freitas, H. (2008) Effects of inoculation of plant growth promoting bacteria on Ni uptake by indian mustard. Bioresource Technology. 99, 3491–3498. (see details)

Gouveia, A.C. & Freitas, H. (2008) Intraspecific competition and water use efficiency in Quercus suber: evidence of an optimum tree density?. Trees. 22, 521-530. (see details)
Link: http://dx.doi.org/10.1007/s00468-008-0212-0

Schreck Reis C., Antunes do Carmo J., Freitas H., , , , (2008) Learning with nature: A sand dune system case-study (Portugal). Journal of Coastal Research . 24, 6, 1506-1515. (see details)

Rajkumar, M., Freitas, H. (2008) Influence of metal resistant-plant growth promoting bacteria on the growth of Ricinus communis in soil contaminted with heavy metals. Chemosphere . 71, 834-842. (see details)

Schreck Reis C., Freitas H., van der Putten W.H. (2008) Responses of roo-feeding nematodes (Helicotylenchus spp.) to local and non-local populations of the host plant Ammophila arenaria. Applied Soil Ecology (in press). (see details)

Rajkumar, M., K.J. Lee and Freitas, H. (2008) Effects of chitin and salicylic acid on biological control activity of Pseudomonas spp. againts damping off of pepper.. South African Journal of Botany . 64, 268-273. (see details)

Robin J. Pakeman, Eric Garnier, Sandra Lavorel, Pauline Ansquer, Helena Castro, Pablo Cruz, Jiri Doležal, Ove Eriksson, Helena Freitas, Carly Golodets, Jaime Kigel, Michael Kleyer, Jan Lepš, Tonia Mei (2008) Impact of abundance weighting on the response of seed traits to climate and land use. Journal of Ecology . 96 , 2, 355–366 . (see details)
Link: doi:10.1111/j.1365-2745.2007.01336.x

Marchante, E., Kjøller, A., Struwe, S., Freitas, H. (2008) Short and long-term impacts of Acacia longifolia invasion on the belowground processes of a Mediterranean coastal dune ecosystem. Applied Soil Ecology. 40, 210-217. (see details)
Link: doi:10.1016/j.apsoil.2008.04.004

M. Rajkumar., Y. Ma., H. Freitas (2008) Charecterization of metal resistant plant growth promoting Bacillus weihenstephanensis isolated from serpentine soil in Portugal.. Journal of Basic Microbiology (Accepted). . 48, 1-9. (see details)

Elizabete Marchante, Annelise Kjøller, Sten Struwe, Helena Freitas (2008) Invasive Acacia longifolia induce changes in the microbial catabolic diversity of sand dunes. Soil Biology & Biochemistry. 40, 2563-2568. (see details)
Link: doi:10.1016/j.soilbio.2008.06.017

Bandeira de Albuquerque M., Kanoun-Boulé M., Freitas H., Prasad M.N.V. (2008) Erica andevalensis - Potential use for phytoremediation of the abandoned copper mine of São Domingos, Portugal. Proceedings of the Joint Conference of the 6th International Acida Sulfate Soil conference and The Acid Rock Drainage Symposium. 20/23. (see details)

Kanoun-Boulé M., Vicente J.A.F., Nabais C., Prasad M.N.V., Freitas H. (2008) Ecophysiological tolerance of duckweeds exposed to copper. Aquatic Toxicology. (see details)
Link: http://dx.doi.org/10.1016/j.aquatox.2008.09.009

BANDEIRA DE ALBUQUERQUE, M, RODRÍGUEZ-ECHEVERRÍA, S., FREITAS, H. (2008) Genetic diversity in populations of Erica andevalensis, a vulnerable metallophyte species from the Iberian Peninsula.. Web of Ecology. 8, 135-141. (see details)

Azul AM, Agerer R, Martín MP, Freitas H (2008) “Quercirhiza tomenteloreticulata” + Quercus suber L. Descr. Ectomyc. 11/12, 135-139. (see details)

Azul AM, Agerer R, Martín MP, Freitas H (2008) “Quercirhiza tomentelloepidermoidea” + Quercus suber L. Descr. Ectomyc. 11/12, 131-134. (see details)

Azul AM, Agerer R, Martín MP, Freitas H (2008) “Quercirhiza tomentellocumulata” + Quercus suber L. Descr. Ectomyc. 11/12, 125-130. (see details)

Azul AM, Agerer R, Martín MP, Freitas H (2008) “Quercirhiza tomentellostellata” + Quercus suber L. Descr. Ectomyc. 11/12, 141-146. (see details)

Castro, H., Alcazar, R., Freitas, H. (2008) Reposnse of plant functional attributes to extensive agricultural practices. Two case studies from Alentejo South Portugal. Les Cahiers d'Orphée. 1, 173-182. (see details)

Castro, P., Valiela, I., Freitas, H. (2007) The use of sedimentary %C, %N, δ15N, and Pb concentrations to assess historical changes in anthropogenic influence on Portuguese estuaries. Environmental Pollution. 147, 3, 706-712. (see details)
Link: http://10.1016/j.envpol.2006.09.011

Silva, H., Caldeira, G. & Freitas, H. (2007) Salicornia ramosissima population dynamics and tolerance of salinity.. Ecol. Research. 22, 125-134. (see details)

Marta-Pedroso, C., Freitas , H.& Domingos, T. (2007) Testing for the survey mode effect on contingent valuation data quality: A case study of web based versus in-person interviews. . Ecol. Econ. (2007), doi:10.1016/j.ecolecon.2007.02.005. 62, 3-4, 388-398. (see details)

Sara Maltez-Mouro, Luis V. García, Teodoro Marañón, and Helena Freitas. (2007) Recruitment patterns in a Mediterranean oak forest: a case study showing the importance of the spatial component. Forest Science. 53, 6, 645-652. (see details)

Gonçalves M.T., Gonçalves S.C., Portugal A., Silva S., Sousa J.P. & Freitas H. (2007) Effects of nickel hyperaccumulation in Alyssum pintodasilvae on model arthropods representatives of two trophic levels. Plant and Soil. 293, 177-188. (see details)
Link: http://dx.doi.org/10.1007/s11104-006-9174-4

Garnier E., Lavorel S., Ansquer P., Castro H., Cruz P., Dolezal J.,Eriksson O., Fortunel C., Freitas H., Golodets C., Grigulis K., Jouany C., Kazakou E., Kigel J., Kleyer M., Lehsten V., Lepš J., Meie (2007) Assessing the effects of land use change on plant traits, communities and ecosystem functioning in grasslands: a standardized methodology and lessons from an application to 11 European sites. Annals of Botany. 99, 967-985. (see details)

García, L. V., Maltez-Mouro, S., Pérez-Ramos, I. M., Freitas, H. and Marañón, T. (2007) Counteracting gradients of light and soil nutrients in the understorey of Mediterranean oak forests. Web Ecology. 6, 67-74. (see details)

Crisóstomo, J.A., Freitas, H., Rodríguez-Echeverría, S. (2007) Comparison between relative growth rates of three woody legumes: implications in the process of ecological invasion. Web Ecology. 7, 22-26. (see details)
Link: http://www.oikos.ekol.lu.se/wepdfs/Web_Ecol.7.22-26.pdf

Campelo, F., Nabais, C., Gutierrez, E. and Freitas, H. (2007) Climatic significance of intra-annual density fluctuations in Pinus pinea from a dry Mediterranean area (Portugal). Annals of Forest Science. 64, 2, 229-238. (see details)
Link: http://www.afs-journal.org/index.php?option=article&access=standard&Item...

Campelo F., Gutiérrez, E., Ribas, M., Nabais, C. and Freitas, H. (2007) Relationships between climate and double rings in Quercus ilex from NE Spain. Canadian Journal of Forest Research. 37, 10, 1915-1923. (see details)
Link: http://rparticle.web-p.cisti.nrc.ca/rparticle/AbstractTemplateServlet?jo...

Araújo, G.C.L., Lemos, S.G., Ferreira, A.G. , Freitas,H. Nogueira, A.R.A. (2007) Effect of pre-treatment and supporting media on Ni(II), Cu(II), Al(III) and Fe(III) sorption by plant root material. Chemosphere. 68, 3, 537-545. (see details)

Rodríguez-Echeverría, S., Crisóstomo, J.A., Freitas, H. (2007) Genetic diversity of rhizobia associated with Acacia longifolia in two stages of invasion of coastal sand dunes. Applied and Environmental Microbiology. 73, 15, 5066-5070. (see details)
Link: doi:10.1128/AEM.00613-07

Ribeiro, P. Paiva, J. & Freitas, H. (2007) Narcissus × caramulensis (Amaryllidaceae), a new hybrid for the portuguese flora. Anales del Jardín Botánico de Madrid. 64, 1, 43-46. (see details)

Castro, P., Valiela, I., Freitas, H., (2007) Eutrophication in Portuguese estuaries evidenced by δ15N of macrophytes. Marine Ecology Progress Series/ MEPS . 351, 9, 43-51. (see details)

Gonçalves S.C.*, Portugal A.*, Gonçalves M.T., Vieira R., Martins-Loução M.A. & Freitas H. (2007) Genetic diversity and differential in vitro responses to Ni in Cenococcum geophilum isolates from serpentine soils in Portugal. Mycorrhiza. 17, 677-687 (* denotes first co-authorship). (see details)
Link: http://dx.doi.org/10.1007/s00572-007-0145-2

Cristina Marta-Pedroso,Tiago Domingos, Helena Freitas, Rudolf S. de Groot (2007) Cost–benefit analysis of the Zonal Program of Castro Verde (Portugal): Highlighting the trade-off between biodiversity and soil conservation. Soil & Tillage Research. 97, 79–90. (see details)

Almeida, J.D. & Freitas, H. (2006) Exotic Flora of continental Portugal – a reassessment.. Botanica Complutensis. 30, 117-130. (see details)

de la Peña, E., Rodríguez Echeverría, S., Van der Putten, W., Freitas, H., Moens, M. (2006) Mechanism of control of root-feeding nematodes by mycorrhizal fungi in the dune grass Ammophila arenaria. New Phytologist. 4, 169 , 829-840. (see details)
Link: doi:10.1111/j.1469-8137.2005.01602.x

Van der Putten, W., Cook, R., Costa, S., Davies, K.G., Fargette, M., Freitas, H., Hol, W.H., Kerry, B.R., Mateille, T., Moens, M., de la Peña, E., Piśkiewicz, Rodriguez-Echeverria, S. (2006) Nematode Interactions in Nature: Models for Sustainable Control of Nematode Pests of Crop Plants?. Advances in Agronomy. 89, 227-260. (see details)
Link: doi:10.1016/S0065-2113(05)89005-4

Rodriguez-Echeverria & Helena Freitas. (2006) Diversity of AMF associated to Ammophila arenaria ssp. arundinacea in Portuguese sand dunes. Mycorrhiza. 16, 543-552. (see details)
Link: doi:10.1007/s00572-006-0070-9

Barrico ML, Nabais C, Martins MJ and Freitas H. (2006) Effect of the season, land use and soil type on the occurrence of phenolic compounds in two catchments of southern Portugal. Chemosphere. 65, 482-488. (see details)

Antunes do Carmo, J., Schreck Reis, C., Freitas, H. (2006) Successful rehabilitation of a sand dune system.. WIT Transactions on Ecology and the Environment. 88, 195-204. (see details)

Castro, P. and Freitas, H. (2006) Anthropogenic effects and salt marsh loss in the Mondego and Mira estuaries (Portugal). Web Ecology. 6, 59-66. (see details)

J. Pratas, M.N.V.Prasad, H.Freitas & L.Conde. (2005) Plants growing on abandoned mines of Portugal contaminated with As (Arsenic), Sb (Antimony) and W (Tungsten), delineate areas of anomalous soil composition for biogeochemical prospecting and possible mine reclamation. Journal of Geochemical Exploration. 85, 99-107. (see details)

Spehn, E.M., Hector, A., Joshi, J., Scherer-Lorenzen, M., Schmid, B., Beierkuhnlein, C., Caldeira, M. C., Diemer, M., Dimitrakopoulos, P. G., Finn, J. A., Freitas, H., Giller, P. S., Good, J., Harris, (2005) Ecosystem effects of biodiversity manipulations in European grasslands. Ecological Monographs. 75, 37-63. (see details)

Schreck Reis, C., Freitas, H., van der Putten, W.H. (2005) Plant-parasitic nematodes associated with Ammophila arenaria (L.) Link in Portuguese coastal sand dunes. Nematologia Mediterranica. 33, 11-18. (see details)

Maltez-Mouro, S., García, L.V., Marañón, T. & Freitas, H. (2005) The combined role of topography and overstory tree composition in promoting edaphic and floristic heterogeneity in a Mediterranean forest. Ecological Research. 20, 668-677. (see details)

Portugal, A., Vieira, R., Freitas, H. (2005) Caracterização molecular por AFLP de isolados do fungo ectomicorrízico Cenococcum geophilum de solos derivados de formações ultramáficas do NE de Portugal. Revista de Ciências Agrárias. XXVIII, (see details)

Nabais, C., Hagemeyer, J., Freitas, H. (2005) Nitrogen transport in the xylem sap of Quercus ilex: The role of ornithine. Journal of Plant Physiology. 162, 603—606. (see details)

Freitas, H., Prasad, M.N.V. & Pratas, J. (2004) Heavy metals in the plant community of São Domingos, an abandoned mine in SE Portugal: Possible aplications in mine remediation. Environmental International. 1, 30, 65-72. (see details)

Freitas, H., Prasad, M.N.V. & Pratas, J. (2004) Serpentine soil and plant analysis for heavy metals accumulation. Chemosphere. 11, 54, 1625-1642. (see details)

Alados, C. L., Elaich, A. E, Papanastasis, V. P, Ozbek, H., Navarro, T. , Freitas, H. , Larrossi, D. , Vrahnakis, M. , & Cabezudo, B. (2004) Change in plant spatial patterns and diversity along the successional gradient of Mediterranean grazing ecosystems. Ecol. Mod.. 180, 523-535. (see details)

Carla P. Fonseca, Liliana P. Montezinho, C. Nabais, A. R. Tomé, H. Freitas, Carlos F. G. C. Geraldes & M. Margarida C.A. Castro. (2004) Effects of Li+ transport and intracellular binding on Li+/Mg2+ competition in bovine chromaffin cells. Biochimica et Biophysica Acta. 1691, 79-90. (see details)

Marchante H.; Marchante E.; Buscardo E.; Maia J. & Freitas H. (2004) Recovery potential of dune ecosystems invaded by an exotic Acacia species (Acacia longifolia). Weed Technology. 18, 1427-1433. (see details)

Santos J., Schreck Reis C., Gonçalves M.T. & Freitas H., Santos, J., Schreck Reis, C., Gonçalves, M.T., Freitas, H. (2004) Micorrizas em Ammophila arenaria – Comparação entre dois sistemas dunares. Revista de Biologia. 22, 101-108. (see details)

Maltez-Mouro S., García L.V., Marañón T. & Freitas H. (2004) Understory floristic heterogeneity within a Mediterranean oak forest: how much is explained by edaphic, spatial and overstory components?. Revista de Biologia. 23, 121-133. (see details)

Pratas J, Prasad M.N.V., Freitas H., and Conde L. (2004) Pinus pinaster Aiton (maritime pine): a reliable indicator for delineating areas of anomalous soil composi-tion for biogeochemical prospecting of As (Arsenic), Sb (Antimony)and W (Tungsten).. European J Mineral Processing & Envir Protection . 4, 136-143. (see details)

Freitas, H., Prasad, M.N.V., Pratas, J. (2004) Analysis of serpentinophytes from north–east of Portugal for trace metal accumulation––relevance to the management of mine environment. Chemosphere. 54, 1625–1642. (see details)

Prasad, M.N.V. & Freitas, H. (2003) Metal hyperaccumulation in plants - Biodiversity prospecting for phytoremediation technology. (Review article). Electronic Journal of Biotechnology. (see details)
Link: http://ejbiotechnology.ucv.cl/content/vol6/issue3/full/6/index.html

Castro H, Nabais C, Alados CL & Freitas H (2003) Effects of cessation of grazing on leaf-level photosynthesis of Periploca laevigata. App. Veg. Sci.. 6, 255-260. (see details)

Domingos, J.D & Freitas, H. (2002) Acerca de algumas plantas vasculares invasoras em Portugal Continental. Studia Botanica. 21, 27-35. (see details)

Portugal A., Gonçalves S.C., Vieira R. & Freitas H. (2002) Chromosome number in the ectomycorrhizal fungus Cenococcum geophilum from ultramafic soils of NE Portugal. The Nucleus. 45, 14-18. (see details)

Portugal A., Martinho P., Vieira R. & Freitas H. (2001) Molecular characterization of Cenococcum geophilum isolates – a case study. Journal of Mediterranean Ecology. 2, 1, 21-30. (see details)

Portugal A., Martinho P., Vieira R. & Freitas H. (2001) Molecular characterization of Cenococcum geophilum isolates from na ultramafic soil (Portugal). South African Journal of Sciences. 97, 617-619. (see details)

Azul AM, Agerer R, Freitas H (2001) “Quercirhiza ectendotrophica” + Quercus suber L. Descr. Ectomyc. 5, 67-72. (see details)
Link: http://www.deemy.de/

Azul AM, Agerer R, Freitas H (2001) “Quercirhiza internangularis” + Quercus suber L. Descr. Ectomyc. 5, 79-83. (see details)
Link: http://www.deemy.de/

Azul AM, Agerer R, Freitas H (2001) “Quercirhiza pedicae” + Quercus suber L. Descr. Ectomyc. 5, 85-91. (see details)
Link: http://www.deemy.de/

Azul AM, Agerer R, Freitas H (2001) “Quercirhiza russulocystidiata” + Quercus suber L. Descr. Ectomyc. 5, 93-98. (see details)
Link: http://www.deemy.de/

Gonçalves S.C., Martins-Loução M.A. & Freitas H. (2001) Arbuscular mycorrhizas (AM) of Festuca brigantina, an endemic serpentinophyte from Portugal. South African Journal of Science. 97, 571-572. (see details)

Azul AM, Agerer R, Freitas H (2001) “Quercirhiza sclerotiigera” + Quercus suber L. Descr. Ectomyc. 5, 99-105. (see details)
Link: http://www.deemy.de/

Portugal, A., Vieira, R., Freitas, H. (2001) O uso de marcadores genéticos na caracterização de isolados do micobionte Cenococcum geophilum de solos ultramáficos do NE de Portugal.. Revista de Ciências Agrárias. XXIV, 227-238. (see details)

Marchante E., Madeira M. & Freitas H. (2001) Avaliação da colonização ectomicorrízica em plantações experimentais de Eucalyptus globulus. Revista das Ciências Agrárias. XXIV, 3 e 4, 205-212. (see details)

Portugal, A., Vieira, R., Gonçalves, S.C., Freitas, H. (2001) Aspectos cariológicos do fungo ectomicorrízico Cenococcum geophilum de áreas ultramáficas do NE Portugal. Boletim da Sociedade Broteriana . LXX, 153-161. (see details)

Hector, A., Schmid, B., Beierkuhnlein, C., Caldeira, M. C., Diemer, M., Dimitrakopoulos, P. G., Finn, J. A., Freitas, H., Giller, P. S., Good, J., Harris, R., Högberg, P., Huss-Danell, K., Joshi, J.,, Lawton, J. H. (2000) No consistent effect of plant diversity on productivity : Response. . Science (Washington, D.C.). 289, 1255a. (see details)

Prasad, M. N. V. & Freitas, H. (2000) Removal of toxic metals from the aqueous solution by the leaf, stem and root phytomass of Quercus ilex L. – potential scope for the application in wastewater treatment. Environmental Pollution. 110, 277-283. (see details)

Castro, Paula, Freitas, Helena (2000) Fungal biomass and decomposition in Spartina maritima leaves in the Mondego salt marsh (Portugal). Hydrobiologia. 428, 171-177. (see details)

Hector, A. Schmid, B., Beierkuhnlein, C. , Caldeira, M.C., Diemer, M., Dimitrakopoulos, P.G., Finn, J., Freitas, H., Giller, P.S., Good, J., Harris, R., Högberg, P., Huss-Danell, K., Joshi, J., Jumppo (1999) Plant diversity and production in European grasslands. Science. 286, 1123-1127. (see details)

Nabais C, Freitas H & Hagemeyer J (1999) Dendroanalysis: a tool for biomonitoring environmental pollution?. The Sci. Total Environm. . 232, 33-37. (see details)

Nabais C, Freitas H & Hagemeyer J (1999) Tree-rings to climate relationships of Quercus ilex L. in NE-Portugal. Dendrochronologia. 16-17, 41-48. (see details)

Prasad, M. N. V. & Freitas, H. (1999) Feasible biotechnological and bioremediation strategies for serpentine soils and mine spoils (Review article). Electronic Journal of Biotechnology. 2, 1, 36-50. (see details)
Link: http://ejb.ucv.cl or http://www.ejb.org

Azul AM, Agerer R, Freitas H (1999) “Quercirhiza nodulosomorpha” + Quercus suber L. Descr. Ectomyc. 4, 103-108. (see details)
Link: http://www.deemy.de/

Castro P. & Freitas H. (1999) Dinâmica do azoto no rio Mondego. Revista de Biologia. 17, 241-247. (see details)

Azul AM & Freitas H. (1998) “Estudo da micorrização de Q. suber L. em condições naturais (populações de Grândola e Santiago do Cacém). Revista de Biologia. 16, 231-234. (see details)

Campelo F., Marchante H., Martins M.J. & Freitas H. (1998) Contribuição para o Estudo Evolutivo da Paisagem no Concelho de Montemor-o-Velho. Revista de Biologia. 16, 279-283. (see details)

Castro P. & Freitas H. (1998) Regulação iónica em folhas senescentes de Spartina maritima. Revista de Biologia. (Lisboa). 16, 217-220. (see details)

Reis, C. S., Freitas, H. (1998) Monitorização de Ammophila arenaria em ecossistemas dunares portugueses. Revista de Biologia. 16, 1-4, 211-215. (see details)

Nabais C, Freitas H, Hagemeyer J & Breckle S-W (1996) Radial distribution of Ni in stemwood of Quercus ilex L. trees grown on serpentine and sandy loam (umbric leptosol) soils of NE-Portugal. Plant and Soil. 183, 181-185. (see details)

Freitas, H. & Mooney, H. (1996) Effects of water stress and soil texture on the performance of two genotypes of Bromus hordeaceus from sandstone and serpentine soils.. Acta Oecologica . 17, 307-317. (see details)

Freitas, H. & Breckle, S.-W (1993) Progressive cutinization in Atriplex bladder stalk cells.. Flora. 188, 287-290. (see details)

Freitas, H. & Breckle, S.-W. (1993) Accumulation of nitrate in bladder hairs of some Atriplex species.. Plant Physiol. Biochem. . 31, 6, 887-892. (see details)

Freitas, H. & Breckle, S.-W. (1992) Importance of bladder hairs for salt tolerance of field-grown Atriplex species of a Portuguese salt marsh. Flora. 187, 283-297. (see details)

Breckle, S.-W., Freitas, H. & Reimann, C. (1990) A new method for sampling Atriplex bladders. Plant, Cell and Environment. 13, 871-873. (see details)

Gonçalves S.C., Sedlmayr A., Castro H., Gonçalves M.T. & Freitas H. (2005) Diversidade de tipos de micorrizas em áreas sujeitas a diferentes usos do solo. Revista de Biologia. 23, 23-34. (see details)

Marchante, E., Freitas, H. & Marchante, H.(2009) Guia Prático para a Identificação de Plantas Invasoras de Portugal Continental. Coimbra. Imprensa da Universidade de Coimbra. 183. pp see details

Marchante H.; Marchante E. & Freitas H.(2005) Plantas Invasoras em Portugal – guia para identificação e controlo. Coimbra. Ed. dos autores. see details Link:
http://www.uc.pt/invasoras/resultados/fichas/especies_perfis.htm

Traça de Almeida, A., Freitas, H. & Figueiredo, M.(2005) Investir nas Florestas Portuguesas. Florestas e Desenvolvimento Sustentável.. Universidade de Coimbra. Imprensa da Universidade de Coimbra.. Vol 1. see details

Kanoun-Boulé M., Bandeira de Albuquerque M., Nabais C., Freitas H.(in press) Copper as an Environmental contaminant: Phytotoxicity and Human Health Implications In: Trace Elements: Nutritional Benefits, Environmental Contamination, and Health Implications. M.N.V. Prasad. (eds) John Wiley and Sons, Inc..

see details

Marchante, E., Kjøller, A., Struwe, S., Freitas, H.(2008) Soil microbial activity in dune ecosystems invaded by Acacia longifolia (Andrews) Willd In: Plant Invasions: Human perception, ecological impacts and management. B. Tokarska-Guzik, J. Brock, G. Brundu, L. Child, C. Daehler & P. Pyšek. (eds) Backhuys Publisher. Leiden, The Netherlands. 247-257pp see details

Nabais C., Barrico M.L., Freitas H., Prasad M.N.V.(2007) Agriculture-induced contamination of surface water and groundwater in Portugal In: Concepts and Applications in Environmental Geochemistry. S. Sarkar, R. Datta and R. Hannigan. (eds) Elsevier. 197-208pp see details

Nabais C., Gonçalves S.C. & Freitas H.(2007) Phytoremediation in Portugal – present and future In: Phytoremediation – Methods and Reviews. Neil Willey. (eds) Methods in Biotechnology. The Humana Press Inc. Totowa. Vol 23. 405-422pp see details Link:
http://www.humanapress.com

RODRÍGUEZ ECHEVERRÍA, S., COSTA, S.R., FREITAS, H.(2007) Biodiversity and interactions in the rhizosphere: effects on ecosystem functioning In: Handbook of functional Plant Ecology, 2nd Edition.. CRC. . 581-600pp see details

Azul AM, Agerer R, Martín MP, Freitas H(2006) Quercirhiza summatriangularis In: Colour Atlas of Ectomycorrhizae. Agerer R. (eds) Einhorn-Verlag, Schwäbisch Gmünd. see details

Azul AM, Azul AM, Agerer R, Martín MP, Freitas H, Agerer R, Freitas H(2006) Quercirhiza tomentellocystidiata In: Colour Atlas of Ectomycorrhizae. Agerer R. (eds) Einhorn-Verlag, Schwäbisch Gmünd. see details

Alados. C, Ahmed ElAich, Vasilios P. Papanastasis, Huseyin Ozbek, Helena Freitas(2006) Monitoring tools to assess vegetation successional regression and predict catastrophic shifts and desertification in mediterranean rangeland ecosystems. W.P. Kepner, J.L. Rubio, D.A. Mouat & F. Pedrazzini, eds. (eds) Desertification in the Mediterranean Region: a Security issue. Springer. NATO Security through Science Series. 431-449pp see details

Freitas, H.(2006) Land-use/Land-cover changes and biodiversity loss. In: Encyclopedia of Life Support Systems. EOLSS,. Eolss Publishers. Oxford, UK. see details Link:
http://www.eolss.net

Freitas, Helena(2006) Biodiversity. Our Earth’s Changing Land. In: An Encyclopedia of Land-Cover Change.. Helmut Geist. (eds) Greenwood Press. London. Vol 1: A-K.. 59-64pp see details

J. S. Pereira, A. Vaz Correia, A. Cristina Correia, M.T. Ferreira, N. Onofre, H. Feitas, F. Godinho.(2006) Florestas e Biodiversidade. In: Alterações Climáticas em Portugal. Cenários, Impactos e Medidas de Adaptação. Projecto SIAM II.. F.D. Santos e P. Miranda (eds). . (eds) Edições Gradiva. Lisboa. see details

Azul AM, Agerer R, Freitas H(2006) Quercirhiza stelladuplicata In: Colour Atlas of Ectomycorrhizae. Agerer R. (eds) Einhorn-Verlag, Schwäbisch Gmünd. see details

Azul AM, Martín MP, Agerer R, Freitas H(2006) Quercirhiza flavocystidiata In: Colour Atlas of Ectomycorrhizae. Agerer R. (eds) Einhorn-Verlag, Schwäbisch Gmünd. see details

Azul AM, Agerer R, Freitas H(2006) Quercirhiza annelata In: Colour Atlas of Ectomycorrhizae. Agerer R. (eds) Einhorn-Verlag, Schwäbisch Gmünd. see details

Azul AM, Agerer R, Freitas H(2006) Quercirhiza dendrohyfidiomorpha In: Colour Atlas of Ectomycorrhizae. Agerer R. (eds) Einhorn-Verlag, Schwäbisch Gmünd. see details

Azul AM, Martín MP, Agerer R, Freitas H(2006) Quercirhiza auraterocystidiata In: Colour Atlas of Ectomycorrhizae. Agerer R. (eds) Einhorn-Verlag, Schwäbisch Gmünd. see details

Azul AM, Agerer R, Freitas H(2006) Quercirhiza ateracusrugosa In: Colour Atlas of Ectomycorrhizae. Agerer R. (eds) Einhorn-Verlag, Schwäbisch Gmünd. see details

Azul AM, Agerer R, Freitas H(2006) Quercirhiza sclerotiigera In: Colour Atlas of Ectomycorrhizae. Agerer R. (eds) Einhorn-Verlag, Schwäbisch Gmünd. see details

Azul AM, Agerer R, Freitas H(2006) Quercirhiza internangularis In: Colour Atlas of Ectomycorrhizae. Agerer R. (eds) Einhorn-Verlag, Schwäbisch Gmünd. see details

Azul AM, Agerer R, Freitas H(2006) Quercirhiza ectendotrophica In: Colour Atlas of Ectomycorrhizae. Agerer R. (eds) Einhorn-Verlag, Schwäbisch Gmünd. see details

Azul AM, Agerer R, Freitas H(2006) Quercirhiza pedicae In: Colour Atlas of Ectomycorrhizae. Agerer R. (eds) Einhorn-Verlag, Schwäbisch Gmünd. see details

Prasad, M.N.V., Prasad, M.N.V., Freitas, H., Freitas, H., Pratas, J. 2005(2005) Metal tolerant plants and biodiversity prospecting to promote phytotechnologies for cleanup of metals in the environment. Chap. 25 In: Trace elements in the environment: Biogeochemistry, Biotechnology and Bioremediation. M.N.V. Prasad, K.S.Sajwan, and Ravi Naidu (Eds). (eds) CRCPress, USA. 483-506pp see details

Prasad, M.N.V., Freitas, H., Pratas, J.(2005) Trace elements in plants and soils of abandoned mines from Portugal: significance for phytomanagement and biogeochemical prospecting. Chap. 26 In: Trace elements in the environment: Biogeochemistry, Biotechnology and Bioremediation. M.N.V. Prasad, K.S.Sajwan, and Ravi Naidu (Eds). (eds) CRCPress, USA. 507-521pp see details

Marchante H.; Marchante E. & Freitas H.(2003) Invasion of the Portuguese dune ecosystems by the exotic species Acacia longifolia (Andrews) Willd.: effects at the community level In: Plant Invasions: Ecological Threats and Management Solutions. Child L.E.; Brock J.H.; Brundu G; Prach K.; Pysek P.; Wade P.M. & Williamson M. (eds) Backhuys Publishers. The Netherlands. 75-85pp see details

Castro, P., Marques JC, Freitas, H., Pardal MA, Maranhão P(2002) Nitrogen dynamics in the Mondego estuary: leaf senescence and N mobilization in Spartina maritima. Capítulo 3.7 In: Aquatic Ecology of the Mondego River Basin. Global importance of local experience. Pardal M. A., Marques, J. C. & Graça, M. A. S.. (eds) Imprensa da Universidade de Coimbra. Coimbra. 313-324pp see details

Nabais, C., Hagemeyer, J., Freitas, H.(2001) Tree Rings and Dendroanalysis In: Metals in the Environment: Analysis by Biodiversity. M.N.V. Prasad. Marcel Dekker Pub.. (eds) New York, USA. 367-400pp see details

Azul AM, Freitas H(1999) “Mycorrhizal fungi and their application to forestation programmes with cork oak (Quercus suber L.)” In: Micorrización en las áreas Mediterraneas de la Peninsula Ibérica. F.M.V. Pardo, S.R. Hércules, S.R. Maqueda & E.D. Pérez. (eds) Junta de Extremadura, Cáceres. 75-82pp see details

Azul, A M, Agerer, R., Freitas, H.(1999) “Quercirhiza nodulosomorpha” + Quercus suber L In: Descriptions of Ectomycorrhizae. Agerer R., Danielson RM, Egli S, Ingleby K, Luoma D, Treu R (eds). (eds) Vol 4. 103-108pp see details

Freitas, H.(1999) Functional diversity In: Handbook of Functional Plant Ecology. F.I. Pugnaire & F. Valladares, Marcel Dekker, Inc.. (eds) New York. 719-733pp see details

Nabais, C., Freitas, H., Hagemeyer, J.(1997) Seasonal variations of aminoacids and organic acids in the xylem sap of Quercus ilex growing on serpentine and sandy loam soils In: Plant Nutrition - for Sustainable Food Production and Environment. T Ando, K Fujita, T Mae, H Matsumoto, S Mori, and J Sekiya. (eds) Kluwer Academic Publishers. Dordrecht. 405-406pp see details

Barrico M.L.(2004) Natureza e origem de compostos fenólicos nas bacias hidrográficas das albufeiras de Santa Clara e do Roxo, Alentejo.. Departamento de Botânica. Faculdade de Ciências e Tecnologia da Universidade de Coimbra. Coimbra. Mestrado. 105pp. see details

Portugal, A.(2004) Genetic variability and multi-loci analysis in isolates of the ectomycorrhizal fungus Cenoccocum geophilum from the NE Portugal ultramafic areas.. Departament of Botany. Universidade de Coimbra. Coimbra. PhD. 123pp. see details

(2002) 2002 – Castro, P. & Freitas, H. Nitrogen dynamics in the Mondego estuary: leaf senescence and N mobilization in Spartina maritima. In Pardal M. A., Marques, J. C. & Graça, M. A. S. (eds). Aquatic Ecology of the Mondego River Basin. Global importance of local experience. Capítulo 3.7: 313-324, Imprensa da Universidade de Coimbra, Coimbra.. see details

Azul AM.(2002) Diversidade de fungos ectomicorrízicos em ecossistemas de Montado. Coimbra University. 769pp. see details

Castro H.(2002) Ecofisiologia de Periploca laevigata: Efeito do pastoreio na nutrição e fotossíntese. University of Coimbra. MSc. thesis. see details

Marchante, E.(2002) Avaliação da colonização ectomicorrízica em plantações experimentais de Eucalyptus globulus Labill. sujeitas a tratamentos de gestão de resíduos orgânicos e fertilização (Effect of fertilization and organic matter management practices on ectomycorrhizas of Eucalyptus globulus plantations). Departamento de Zoologia. Faculdade de Ciências e Tecnologia da Universidade de Coimbra. Coimbra. Mestrado. see details

(2001) Invasão dos ecossistemas dunares portugueses por Acacia: uma ameaça para a biodiversidade nativa /Invasion of the Portuguese dune ecosystem by Acacia: a threat to native biodiversity. Faculdade de Ciências e Tecnologia. Universidade de Coimbra. Coimbra. Mestrado/ MSc. 147pp. see details

Nabais, C.(2000) Seasonal transport, allocation and speciation of nickel in Quercus ilex trees grown on serpentine and nickel spiked soil. University of Coimbra. PhD Thesis. 167pp. see details

Gonçalves S.C.(2000) Mycorrhizas in Festuca brigantina: functioning and ecological meaning. University of Coimbra. Master thesis. 56pp. see details

Azul AM.(1999) Ectomicorrizas associadas ao sobreiro (Quercus suber L.) . Coimbra University. MSc. Thesis. 195pp. see details

Nabais, C.(1995) Dendroanalyse of Quercus ilex in serpentine areas of north-east Portugal. University of Coimbra. Master Thesis. 84pp. see details

Gonçalves, S.C., Barrico, L. Portugal, A., Pilz, D., Freitas, H. & Gonçalves, M.T. (2007) Productivity of Tricholoma flavovirens and other edible mushrooms in maritime pine forests in Portugal: effect of thinning regimes. Abstracts from the 1st World Conference on the Conservation and Sustainable Use of Wild Fungi (World Fungi 2007). 10-17 December, Cordoba, Spain. see details

Portugal, A., Bidartondo, M., Rodríguez-Echeverría, S., Gonçalves, S.C., Freitas, H. & Gonçalves, M.T. (2007) Contribution to the molecular delimitation of the Tricholoma flavovirens species complex. Abstracts from the 1st World Conference on the Conservation and Sustainable Use of Wild Fungi (World Fungi 2007). 10-17 December, Cordoba, Spain. see details

(2006) Rodríguez-Echeverría, S., Crisóstomo, J.A., Marchante, E., Pérez-Fernández, M.A., Gallardo, A. & Freitas, H. Diversidad rizobiana asciada a Acacia longifolia en la Reserva Natural de las Dunas de São Jacinto (ORAL PRESENTATION) 2º Congresso Ibérico de Ecologia. Lisboa (Portugal) 18-21 July-2006 . see details

(2006) Rodríguez-Echeverría, S. & Freitas, H.Diversidad morfológica y genética de Ammophila arenaria (L.) Link en la costa europea. 2º Congresso Ibérico de Ecologia. Lisboa (Portugal) 18-21 July-2006. see details

(2006) Crisóstomo, J.A., Rodríguez-Echeverría, S., Costa, S.R. & Freitas, H. Comparação da taxa de crescimento de três espécies de leguminosas lenhosas: implicações no proceso de invasão ecológica. 2º Congresso Ibérico de Ecologia. Lisboa (Portugal) 18-21 July- 2006 . see details

Rodriguez-Echeverria, S, de la Peña, E., Freitas, H. (2006) Insights into the control of root-feeding nematodes by arbuscular mycorrhizal fungi . 5th International Conference on Mycorrhiza. 23-27, Granada, Spain. see details

(2006) Crisóstomo, J.A., Rodríguez-Echeverría, S. & Freitas, H. AM fungi diversity associated with three woody legumes in the Reserva Natural de São Jacinto, Portugal. 5th International Conference on Mycorrhiza. Granada (Spain) 23-27 July -2006 . see details

(2006) 2006. ICOM V. 5th International Conference on Mycorrhiza, Granada, Spain, 23-27 July. Oral Communication: Azul AM, Martín MP, Agerer R, Sousa JP & Freitas H “Land-use history and ectomycorrhizal fungi richness and diversity patterns in managed European Mediterranean oak woodlands: Alentejo region, Portugal”.. see details

(2006) 2006. ICOM V. 5th International Conference on Mycorrhiza, Granada, Spain, 23-27 July. Poster: Azul AM, Ramos V & Sales F “Vegetation cover diversity and mycorrhizal fungi patterns in a biogenetic reserve: after fire communities in Serra da Estrela grassland, Portugal.”. see details

(2006) 2006 - Padrão espacial das plântulas de quatro espécies lenhosas num bosque misto de carvalhos: o papel da estrutura e da composição específica da canópia. Maltez-Mouro S., García L.V, Marañón T. & Freitas H. 2º Congresso Ibérico de Ecologia (18-21 Julho) Lisboa.. see details

(2006) • KANOUN M., FREITAS H. 2006 (In preparation). Ecophysiological responses of ecotypes of Lemna minor and Spiodela polyrrhiza to trace metal exposure. 10th International Conference on Wetland Systems for Water Pollution Control. International Water Association. 23-29 September, Lisbon (Portugal). . see details

Gonçalves S.C., Bona E., Martins-Loução M.A., Freitas H. & Berta G. (2006) Nickel-induced protein pattern modifications in a serpentine tolerant isolate of the ectomycorrhizal fungus Cenococcum geophilum. Abstracts from the 5th International Conference on Serpentine Ecology. 9-13 May, Siena, Italy. see details

Marchante E., Marchante H., Freitas H. (2006) Recovery potential of coastal dunes invaded by Acacia longifolia. International Symposium on Intractable Weeds and Plant Invaders. 17-21 July, S. Miguel, Azores, Portugal. see details

Portugal, A., Gonçalves, S.C., Gonçalves, M.T., Vieira, R., Martins-Loução, M.A., Freitas, H. (2006) Diversity of Cenococcum geophilum isolates from serpentine soils of NE Portugal assessed by AFLP and in vitro Ni tolerance. V International Conference on Serpentine Ecology. 9-13 May, Siena, Italy. see details

(2006) • KANOUN M., FREITAS H. 2006 (In preparation). Impact of pH and trace metals bioavailability on the colonisation of the drainage water of São Domingos mine (Portugal) by Lemna minor. Bioavailability of Pollutants and Soil Remediation Workshop. 11-13 September 2006, Sevilla (Spain).. see details

Kanoun-Boulé M., Vicente J., Freitas H. (2006) Ecophysiological responses of ecotypes of Lemna minor and Spirodela polyrrhiza to trace metal exposure.. 10th International Conference on Wetland Systems for Water Pollution Control. International Water Association. . 23-29 September, Lisbon , Portugal. see details

(2005) Underground relationships between arbuscular mycorrhizal fungi and endoparasitic nematodes in coastal sand dunes. Rodríguez-Echeverría, S., de la Peña, E., Moens, M. & Freitas, H. IOBC-meeting “Multitrophic interactions in the soil”. Wageningen 2005.. see details

(2005) Castro, H. & Freitas, H. 2005. Land use changes, plant functional traits and ecosystem processes. 35th Annual Conference of the Ecological Society, "Landscapes, ecosystems and populations - dynamics, functions and conservation". Regensburg, Germany, 19 - 23 of September. Poster. . see details

(2005) Castro, H. & Freitas, H. 2005. Effect of land use changes on species richness and plant functional traits. 48th International Association Vegetation Science Symposium. Lisbon, Portugal, 24 - 29 July. Oral communication.. see details

(2005) Castro, H., Alcazar, R. & Freitas, H. 2005. Response of plant functional attributes to extensive agriculture practices. Two case studies from Alentejo, South Portugal. International Symposium VISTA - WP5, "Tools for the Management of Natural Grassland". Toulouse, France, 6 - 8 of July. Oral communication.. see details

(2005) • KANOUN M., BANDERA DE ALBUQUERQUE M., FREITAS H. 2005 Trace metal tolerance of Erica andevalensis: a potential for phytomanagement of degraded mining soils. 48ThInternationalAssociationforVegetationScienceSymposium. ''Marginal landscapes (and nutrient-poor ecosystems)-processes and adaptation''. 24-29 July, Lisbon (Portugal) Abstract Book, P-101.. see details

Gonçalves M.T., Gonçalves S.C., Portugal A, Campelo F., Martins M.J., Nabais C. & Freitas H. (2005) The MÍSCARO project: ecology and management of the commercially harvested Tricholoma flavovirens in maritime pine forests of Beira Litoral, Portugal. Abstracts from the 4th International Workshop on Edible Mycorrhizal Mushrooms. 29 Nov - 2 Dec, Murcia, Spain. see details

Marchante H., Santos C. & Freitas H (2005) Evaluation of seed bank composition as a tool to assess invaded system restoration potential (poster). SER conference on Ecological Restoration: a global challenge. 12 - 18 September, Zaragoza, Spain. see details

Marchante, E., Kjøller, A., Struwe, S., Freitas, H. (2005) Soil microbiological effects of the invasive species Acacia longifolia. 8th International Conference on the "Ecology and Management of Alien Plant Invasion" . 5-12 September, University of Silesia, Katowice, Poland. see details

Marchante, H., Marchante, E., Freitas, F. (2005) Invasive plant species in Portugal: an overview. International Workshop on Invasive Plants in Mediterranean Type Regions of the World. 25-27 May, Montpellier, France. see details

Marchante, H., Marchante, E., Freitas, H. (2005) Contribution for the management of dune ecosystems invaded by Acacia longifolia (Andrews) Wild: a case study from Portugal. International Workshop on Invasive Plants in Mediterranean Type Regions of the World. 25-27 May, Montpellier, France. see details

Pereira, A.J., Pinto, M.J., Marchante, H., Marchante, E., Schreck, C., Freitas, H., Ferreira, J., Martins-Loução, M.A., Correia, O., Máguas, C. (2005) Two different patterns of Acacia spp. invasion in coastal dune ecosystems (Portugal): with and without disturbance. 8th International Conference on the "Ecology and Management of Alien Plant Invasion". 5 -12 September, University of Silesia, Katowice, Poland. see details

Santos C., Marchante H., Freitas H. (2005) Seed bank composition in a dune ecosystem invaded by Acacia longifolia. (poster). IAVS symposium on Marginal Landscapes and Nutrient-poor Ecosystems – Processes and Adaptations. 24 - 29 July, Lisbon, Portugal. see details

de la Peña, E., Rodríguez-Echeverría, S., Freitas, H., Moens, M. (2005) Regulation of endoparasitic nematodes in the dune grass Ammophila arenaria: host plant vs. plant mutualists. IOBC-Meeting "Multitrophic interactions in soil". 5-8 June, Wageningen, The Netherlands. see details

Kanoun-Boulé M., Bandeira de Albuquerque M., Freitas H. (2005) Trace metal tolerance of Erica andevalensis: a potential for phytomanagement of degraded mining soils.. 48ThInternationalAssociationforVegetationScienceSymposium. ''Marginal landscapes (and nutrient-poor ecosystems)-processes and adaptation''. 24-29 July, Lisbon, Portugal. see details

Portugal A., Gonçalves S.C., Vieira R. & Freitas H. (2004) Characterization of Cenococcum geophilum isolates from a serpentine area by microsatellite-primed PCR. A tool for future revegetation programmes. Proceedings of the 4th International Conference on Serpentine Ecology. Havana, Cuba. see details

(2004) Santos, J., Sousa, J. P., Gonçalves, M. T. & Freitas H. 2004. Utilização de parâmetros microbianos na avaliação da gestão do solo em ecossistemas de Montado. Resumos do I Encontro Ibérico da Ciência do Solo. Escola Superior Agrária de Bragança, 15 a 18 de Junho. (Oral comunication). see details

(2004) 2004: Arbuscular mycorrhizal fungi associated with Ammophila arenaria L. in European coastal sand dunes. Rodríguez Echeverría, S.; Crisóstomo, J. & Freitas, H. Proceedings of MEDECOS X International Conference Mediterranean Ecology. Rhodes, Greece.. see details

(2004) 2004. Control of plant parasitic nematodes in a natural system: I. Plant variability and their Mutualists (Oral presentation). Susana Rodriguez-Echeverria & Helena Freitas CONFERENCE: Advances in applied biology: providing new opportunities for consumers and producers in the 21st century. Organised by The Association of Applied Biologists. Oxford (Great Britain) . see details

(2004) 2004 - Mouro, S., Pinto, M. J. & Freitas H. Spatial floristic heterogeneity inside an apparently homogeneous Mediterranean forest. Ecology, Conservation and Management of Mediterranean Climate Ecosystems; Proceedings 10th MEDECOS Conference. Margarita Arianoutsou & Vasilios P. Papanastasis (Eds.) Milpress 2004, Rotterdam. . see details

Marchante, H., Buscardo, E., Marchante, E., Freitas, H. (2004) Seed longevity and influence of depth in the germination ability of the invasive species Acacia longifolia seeds in dune ecosystems. Preliminary results. Seed Ecology Conference. 29 April - 4 May, Rhodes Island, Greece. see details

Marchante, H., Freitas, H. (2004) Evaluation of the seed bank composition by seed emergence approach in areas invaded by Acacia longifolia (Andrews) Willd. Seed Ecology Conference. 29 April - 4 May, Rhodes Island, Greece. see details

Marchante, H., Marchante, E., Freitas, H. (2004) Effectiveness of mechanical cutting on Acacia longifolia control. 3rd International Conference on Biological Invasions NEOBIOTA – From Ecology to Control. 30 September - 1 October, Bern, Switzerland. see details

Pereira, A.J., Evangelista, H., Marchante, H., Marchante, E., Schreck, C., Freitas, H., Ramos, M., Correia, O., Máguas, C. (2004) Water use in dune ecosystems: native versus invasive species (Acacia longifolia). VII Simposio Luso-espanhol de relações hídricas em plantas. . 27-29 September, Faro, Portugal. see details

Pereira, A.J., Pinto, M.J., Marchante, H., Marchante, E., Ferreira, J., Schreck, C., Freitas, H., Martins-Loução, M.A., Correia, O., Máguas, C. (2004) Competition ability and resource dynamics in Portuguese coastal dune ecosystems: invasive vs native plant species. Workshop on Water Use of Woody Crops: techniques, issues, modelling and applications on water management. 20th - 21st May, Ilhavo, Portugal. see details

Rodríguez-Echeverría, S., Crisóstomo, J., Freitas, H. (2004) Arbuscular mycorrhizal fungi associated with Ammophila arenaria L. in European coastal sand dunes. Proceedings 10th MEDECOS Conference. 1-7, Rotterdam, see details

(2004) 2004. I Congresso Ibérico da Ciência do Solo, Bragança, Portugal. Poster: Azul AM & Freitas H “Diversidade de fungos ectomicorrízicos associados ao sobreiro em sistemas de Montado”.. see details

Marchante, H., Marchante, E., Buscardo, E., Maia, J., Freitas, H. (2003) Recovery potential of dune ecosystems invaded by Acacia longifolia (Andrews) Willd. 7th International Conference on the Ecology and Management of Alien Plant Invasions + Invasive Plants in Natural and Managed Systems: Linking Science and Management. 3 - 7 November, Ft. Lauderdale, Florida, EUA. see details

Pereira A. J., Pinto, M. J., Marchante, H., Marchante, E., Ferreira, J., Schreck, C., Freitas, H., Martins-Loução, M.A., Correia, O., Máguas, C. (2003) Competition ability and resource dynamics in Portuguese coastal dune ecosystems: invasive vs. native plant species. Invasive Plants in Natural and Managed Systems: Linking science and Management in conjunction with the 7th International Conference on the Ecology and Management of Alien Plant Invasions. 3 - 7 November, Ft. Lauderdale, Florida, USA. see details

Marchante, H., Freitas, H. (2003) Invasion by Acacia longifolia (Andrews) Willd.: a comparison of seed bank availability in invaded and non-invaded dunes. Preliminary results. 7th International Conference on the Ecology and Management of Alien Plant Invasions + Invasive Plants in Natural and Managed Systems: Linking Science and Management”. 3 - 7 November, Ft. Lauderdale, Florida, EUA. see details

(2003) Schreck Reis, C. & Freitas, H. (2003) Ecotypes of Ammophila arenaria in the Portuguese coast. Proceedings of the Sixth International Conference on the Mediterranean Coastal Environment, Medcoast 03, E. Özhan (Editor),Ravenna, Italy, 7-11 October: 1401-1411. . see details

(2003) 2003 – Castro, P; Freitas, H.; Maia, R.; Máguas, C. Using stable-nitrogen (d15N) isotopes to assess N-loading effects in salt marshes. Caricostas 2003: First International Conference on Integrated Coastal Zone Management. Santiago de Cuba, 5 a 7 de Maio.. see details

Freitas, H., Gonçalves, T., Maia, J., Marchante, E., Marchante, H., Reis, M. (2002) Recovery potential of ecosystems invaded by Acacia. Methodologies to control invasion (INVADER). 6th International Conference LITTORAL 2002. 22-26 September, Porto, Portugal. see details

(2002) 2002 – Castro, P. ; Campelo, F. & Freitas, H. Assessing habitat changes in two portuguese estuaries during recent decades. 3rd European Conference on Restoration Ecology: “Changes of the new millennium – our joint responsability”. Budapeste, Hungria, 25 a 31 de Agosto.. see details

(2002) 2002 – Castro, P.; Valiela, I. & Freitas, H. Assessing habitat loss to anthropogenic activity in the Mondego and Mira estuaries (Portugal). 87th Ecological Society of America and 14th Society for Ecological Restoration meeting. “A convocation: understanding and restoring ecosystems”. Tucson, Arizona, E. U. A, 4 a 9 de Agosto.. see details

(2002) Schreck Reis, C., Freitas, H. & van der Putten, W. (2002) Plant-parasitic nematodes associated with Ammophila arenaria (L.) Link in Portuguese coastal sand dunes, Fourth International Congress of Nematology, Tenerife, Spain, 8-13 June; Nematology, 4 (part 2): 275. . see details

Marchante, H., Marchante, E., Freitas, H. (2001) Invasion of Portuguese dune ecosystem by Acacia: evaluation of its effects on soil and plant communities. 6th International Conference on Ecology and Management of Alien Plant Invasions (EMAPi). 12-14 September, Loughborough, United Kingdom. see details

(2001) 2001 – Castro, P.; Freitas, H & Valiela I. Assessing habitat changes during the last decades due to eutrophication in two portuguese estuaries. Proceedings of the 12th Biennial Coastal Zone Conference. Cleveland, E.U.A., 15 a 19 de Julho.. see details

Marchante, H., Marchante, E., Campelo, F., Freitas, H. (2000) N availability in Portuguese coastal sand dunes invaded by the exotic genus Acacia. 9th International Conference on Mediterranean-Type Ecosystems: Past, Present and Future (MEDECOS). 11-15 September, Stellenbosch, South Africa. see details

Marchante, H., Campelo, F., Freitas, H. (2000) Invasion of Portuguese coastal sand dunes by the exotic Acacia longifolia - a threat to native plant biodiversity. 9th International Conference on Mediterranean-Type Ecosystems: Past, Present and Future (MEDECOS). 11-15 September, Stellenbosch, South Africa. see details

(1999) Reis, C. & Freitas, H. (1999) Protection of the Portuguese Coastal Sand Dunes. The importance of biodiversity, Coastal Zone 99 - The People, The Coast, The Ocean – Vision 2020, San Diego, California, USA, 24-30 July: 408. . see details

(1999) 1999 - Castro, P & Freitas H. Fungal importance for leaf senescence and decomposition of Spartina maritima in a Portuguese salt marsh. EURECO'99 – 8th European Ecological Congress, P?170. Halkidiki - Grécia, 18-23 Setembro.. see details

Marchante, E., Madeira, M., Freitas, H. (1999) Effect of different management practices on ectomycorrhizas of Eucalyptus globulus plantations. XIII Congress of European Mycologists (CEM). 21-25 September, Alcalá de Henares, spain. see details

Marchante, H., Campelo, F., Freitas, H. (1999) Impact of the genus Acacia sp. on plant biodiversity of the Portuguese sandy coast. 5th International Conference on the Ecology of Invasive Alien Plants. 13-16 October, Sardenia, Italy. see details

(1998) Reis, C. & Freitas, H. (1998) Population Ecology of Ammophila arenaria in Portuguese coastal sand dunes, Land-Water Interface: Science for a Sustainable Biosphere, St Louis, Missouri, USA, 7-12 June: A-82. . see details

(1998) 1998 – Castro, P & Freitas H. Nitrogen partitioning in Spartina maritima in the Mondego estuary (Portugal). ASLO/ESA - The Land-Water Interface: Science for a Sustainable Biosphere, P-15. St. Louis, Missouri, EUA, 7-12 Junho.. see details

(1998) 1998 - Castro, P & Freitas H. A importância da biomassa fúngica para a senescência e decomposição de Spartina maritima - X Simpósio Ibérico de Estudos de Bentos Marinho, P?53. Praia do Carvoeiro, 23-26 de Fevereiro.. see details

(1997) Nabais, C., Freitas, H. & Hagemeyer, J. (1997) Dendroanalysis: a tool for biomonitoring environmental pollution. A critical assessment. International Workshop on Biomonitoring of Atmospheric Pollution.. see details

Gonçalves S.C., Gonçalves M.T., Freitas H. & Martins-Loução M.A. (1997) Mycorrhizae in a Portuguese serpentine community. Proceedings of the 2nd International Conference on Serpentine Ecology. Noumea, New Caledonia. see details

(1996) Reis, C. & Freitas, H. (1996) Biology of Ammophila arenaria of the Portuguese coastal sand dunes: effects of sand mobility, British Ecological Society Winter Meeting, Durham, 16-19 December. . see details

(1995) 1995 - Castro, P; Marta, C & Freitas, H. Contribuição das halófitas Spartina maritima, Artrocnemum fruticosum e Halimione portucaloides para o ciclo de nitratos num gradiente de eutrofização do sapal do Rio Mondego. IV congresso Luso-Espanhol de Fisiologia Vegetal XI Reunion Nacional de la S. E. F. V., P?29. Estoril, 3-6 Outubro.. see details

(1995) Nabais, C., Freitas, H. & Hagemeyer, J. (1995) Nickel, calcium and magnesium concentrations in xylem rings of Quercus ilex L. from serpentine soils of north?east Portugal. Abstracts of the 3rd International Conference on the Biogeochemistry of Trace Elements, B1. . see details

(1995) 1995 - Marta, C.; Castro, P; Nabais, C & Freitas, H. Contribuição de algumas halófitas para o ciclo de nutrientes do sapal do Mondego. Resumo do 1º Congresso Ibérico sobre Contaminação e Toxicologia Ambiental, P-35, Coimbra, 5 a 8 de Março. . see details

(1993) Nabais, C., Freitas, H., Paiva, J. & Mesquita, J. (1993) Ultrastructural aspects of leaves of Nerium oleander L. from lead polluted and non-polluted sites. Abstracts of the SECOTOX Regional Meeting Environmental Toxicology: hazards to environment and man in the mediterranean region, 154.. see details

(1991) Freitas, H., Nabais, C. & Paiva, J. (1991) Heavy metal pollution in roads of Portugal using Nerium oleander L.. Proceedings of the 8th International Conference Heavy Metals in the Environment, Vol 1, 240-242.. see details

Marchante, H; Campelo, F. & Freitas, H.(in press) Avaliação do impacto de Acacia sobre a diversidade vegetal dos sistemas dunares (Dunas de S.Jacinto e Palheirão). (in press Actas do 1º Simpósio sobre Espécies Exóticas). . see details

Freitas, H.(2005) Biodiversidade e Conservação da Natureza: o contributo da ecologia. Cap. 8.2, In: 20 anos 20 temas, 1985-2005. Associação Portuguesa de engenharia do ambiente.. see details

Azul AM & Freitas H.(2005) Sobre a diversidade de micorrizas e o funcionamento dos ecossistemas florestais mediterrânicos. Anais Associação Micológica a Pantorra 5: 45-58.. see details

Freitas, H.(2004) Breve reflexão sobre o ambiente urbano. Rua Larga, nº 6. Reitoria da Universidade de Coimbra. 15-16.. see details

Freitas, H. & Horta, K.(2003) Proposed Portugal dam would flood culturally rich, biologically diverse area. World Rivers Review, June. 10-11.. see details

Freitas, H.(2003) The risk of indifference: the ultimate challenge for environmental activists and society. In: World Trends in Environmental Education. U. Azeiteiro, F. Gonçalves, W. L. Filho, F. Morgado & M. Pereira (eds). Peter Lang, Frankfurt am Main, Cap. 9: 153-162.. see details

Almeida J.D.; Marchante E.; Marchante H. & Freitas H.(2003) Invasive plant species in Portugal: state of the art. Aliens (Newsletter do Invasive Species Specialist Group of the IUCN) 18: 16-18.. see details

Portugal, A., Freitas, H.(1998) A Biodiversidade do Solo. Pedon 12, 128-134.. see details

Martins M.J.; Caldeira R.; Marchante H.; Campelo F.; Freitas H. & Paiva J.(1997) A flora e vegetação da Serra da Cabreira. Atlas ambiental para a conservação da Serra da Cabreira.. see details