Plant-plant interactions in tropical alpine environments

Perspectives in Plant Ecology, Evolution and Systematics

Volumn 14, Issue 5, 2012, Pages 363-372

  Anthelme, Fabien ^a,b   Dangles, Olivier ^b,c  

^a INSTITUT DE RECHERCHE POUR LE DÉVELOPPEMENT   (France)

^b PONTIFICIA UNIVERSIDAD CATÓLICA DEL ECUADOR   (Ecuador)

^c INSTITUT DE RECHERCHE POUR LE DÉVELOPPEMENT   (France)

Author keywords

Community organization; Competition; Facilitation; Niche differentiation; Nurse effect; Stress gradient hypothesis

Indexed keywords

ALPINE ENVIRONMENT; CONCEPTUAL FRAMEWORK; EXTRATROPICAL ENVIRONMENT; FACILITATION; FREEZE-THAW CYCLE; LATITUDINAL GRADIENT; NICHE PARTITIONING; NURSE PLANT; SPECIES DIVERSITY; TROPICAL ENVIRONMENT;

EAST AFRICA; SOUTH AMERICA; SOUTH ASIA;

EID: 84866338111     PISSN: 14338319     EISSN: 16180437     Source Type: Journal    
DOI: 10.1016/j.ppees.2012.05.002     Document Type: Review

References (124)

1. Albert C.H., Grassein F., Schurr F.M., Vieilledent G., Violle C. When and how should intraspecific variability be considered in trait-based plant ecology?. Persp. Plant Ecol. Evol. Syst. 2011, 13:217-225.
2. Anthelme F., Buendia B., Mazoyer C., Dangles O. Unexpected mechanisms sustain the stress gradient hypothesis in a tropical alpine environment. J. Veg. Sci. 2012, 23:62-72.
3. Anthelme F., Michalet R. Grass-to-tree facilitation in an arid grazed environment (Aïr Mountains Sahara). Basic Appl. Ecol. 2009, 10:437-446.
4. Antonelli A., Sanmartín I. Why are there so many plant species in the Neotropics?. Taxon 2011, 60:403-414.
5. Armas C., Ordiales R., Pugnaire F.I. Measuring plant interactions: a new comparative index. Ecology 2004, 85:2682-2686.
6. Arroyo M.T.K., Cavieres L.A., Castor C., Humana A.M. Persistent soil seed bank and standing vegetation at a high alpine site in the central Chilean Andes. Oecologia 1999, 119:126-132.
7. Badano E.I., Cavieres L.A., Molina-Montenegro M.A., Quiroz C.L. Slope aspect influences plant association patterns in the Mediterranean matorral of central Chile. J. Arid Environ. 2005, 62:93-108.
8. Badano E.I., Jones C.G., Cavieres L.A., Wright J.P. Assessing impacts of ecosystem engineers on community organization: a general approach illustrated by effects of a high-Andean cushion plant. Oikos 2006, 115:369-385.
9. Badano E.I., Marquet P.A. Biogenic habitat creation affects biomass-diversity relationships in plant communities. Perspect. Plant Ecol. Evol. Syst. 2009, 1:191-201.
10. Bannister P., Maegli T., Dickinson K.J.M., Halloy S.R.P., Knight A., Lord J.M., Mark A.F., Spencer K.L. Will loss of snow cover during climatic warming expose New Zealand alpine plants to increased frost damage?. Oecologia 2005, 144:245-256.
11. Barbier N., Couteron P., Lejoly J., Deblauwe V., Lejeune O. Self-organized vegetation patterning as a fingerprint of climate and human impact on semi-arid ecosystems. J. Ecol. 2006, 94:537-547.
12. Barthélémy D., Caraglio Y. Plant architecture: a dynamic, multilevel and comprehensive approach to plant form, structure and ontogeny. Ann. Bot. 2007, 99:375-407.
13. Baumeister D., Callaway R.M. Facilitative effects of Pinus flexilis during succession: a hierarchy of mechanisms benefits other plant species. Ecology 2006, 87:1816-1830.
14. Beck E. Cold tolerance in tropical plants. Tropicalpine Environments: Plant Form and Function 1994, 77-110. Cambridge Univ. Press. P.W. Rundel, A.P. Smith, F.C. Meinzer (Eds.).
15. Bertness M.D., Callaway R.M. Positive associations in communities. Trends Ecol. Evol. 1994, 9:191-193.
16. Billings W.D., Mooney H.A. The ecology of arctic and alpine plants. Biol. Rev. 1968, 43:481-529.
17. Brooker R.W., Callaghan T.V. The balance between positive and negative interactions and its relationship to environmental gradient: a model. Oikos 1998, 81:196-207.
18. Brooker R.W., Maestre F.T., Callaway R.M., Lortie C.L., Cavieres L., Kunstler G., Liancourt P., Tielbörger K., Travis J.M.J., Anthelme F., Armas C., Coll L., Corcket E., Delzon S., Forey E., Kikvidze Z., Olofsson J., Pugnaire F., Quiroz Cl., Saccone P., Schiffers K., Seifan M., Touzard B., Michalet R. Facilitation in plant communities: the past, the present and the future. J. Ecol. 2008, 96:18-34.
19. Burns J.H., Strauss J.Y. More closely related species are more ecologically similar in an experimental test. Proc. Natl. Acad. Sci. U. S. A. 2011, 108:5302-5307.
20. Buytaert W., Cuesta-Camacho F., Tobón C. Potential impacts of climate change on the environmental services of humid tropical alpine regions. Global Ecol. Biogeogr. 2011, 20:19-33.
21. Caldwell M.M., Robberecht R. A steep latitudinal gradient of solar ultraviolet-B radiation in the arctic-alpine life zone. Ecology 1980, 61:600-611.
22. Callaway R.M. Positive Interactions and Interdependence in Plant Communities 2007, Springer.
23. Callaway R.M., Brooker R., Choler P., Kikvidze Z., Lortie C., Michalet R., Paolini L., Pugnaire F., Newingham B., Aschehoug E., Armas C., Kikodze D., Cook B.J. Positive interactions among alpine plants increase with stress. Nature 2002, 417:844-848.
24. Callaway R.M., Walker L.R. Competition and facilitation: a synthetic approach to interactions in plant communities. Ecology 1997, 78:1958-1965.
25. Catorci A., Cesaretti S., Velasquez J.L., Zeballos H. Plant-plant spatial interactions in the dry Puna (southern Peruvian Andes). Alp. Bot. 2011, 121:113-121.
26. Cavieres L.A., Badano E.I. Do facilitative interactions increase species richness at the entire community level?. J. Ecol. 2009, 97:1181-1191.
27. Cavieres L.A., Badano E.I., Sierra-Almeida A., Molina-Montenegro M.A. Positive interactions between alpine plant species and the nurse cushion plant Laretia acaulis do not increase with elevation in the Andes of central Chile. New Phytol. 2006, 169:59-70.
28. Cavieres L.A., Quiroz C., Molina-Montenegro M., Pauchard A. Nurse effect of the native cushion plant Azorella monantha on the invasive non-native Taraxacum officinale in the high-Andes of central Chile. Perspect. Plant Ecol. Syst. Evol. 2005, 7:217-226.
29. Choler P., Michalet R., Callaway R.M. Facilitation and competition on gradients in alpine plant communities. Ecology 2001, 82:3295-3308.
30. Crawford R.M.M. Plants at the Margin: Ecological Limits and Climate Change 2008, Cambridge Univ. Press.
31. Dullinger S., Kleinbauer I., Pauli H., Gottfried M., Brooker R., Nagy L., Theurillat J.P., Holten J.I., Abdaladze O., Benito J.L., Borel J.-L., Coldea G., Ghosn D., Kanka R., Merzouki A., Klettner C., Moiseev P., Molau U., Reiter K., Rossi G., Stanisci A., Tomaselli M., Unterlughauer P., Vittoz P., Grabherr G. Weak and variable relationships between environmental severity and small-scale co-occurrence in alpine plant communities. J. Ecol. 2007, 95:1284-1295.
32. Farji-Brener A.G., Chinchilla F.A., Magrach A., Romero V., Rios M., Velilla M., Serrano J.M., Amador-Vargas S. Slope orientation enhances the nurse effect of the páramo shrub Hypericum irazuense (Hypericaceae) in Costa Rica. J. Trop. Ecol. 2009, 25:331-335.
33. Francou B., Le Méhauté N., Jomelli V. Factors controlling spacing distance of sorted stripes in a low-latitude, alpine environment (Cordillera Real, 16°S, Bolivia). Permafrost and Periglacial Process. 2001, 12:367-377.
34. Fugère V., Andino P., Espinosa R., Anthelme F., Jacobsen D., Dangles O. Testing the stress-gradient hypothesis with aquatic detritivorous invertebrates: insights for biodiversity-ecosystem functioning research. J. Anim. Ecol. Early View 2012, 10.1111/j.1365-2656.2012.01994.x.
35. Gomez-Aparicio L. The role of plant interactions in the restoration of degraded ecosystems: a meta-analysis across life-forms and ecosystems. J. Ecol. 2009, 97:1202-1214.
36. Graff P., Aguiar M.R. Testing the role of biotic stress in the stress-gradient hypothesis. Processes and patterns in arid rangelands. Oikos 2011, 120:1023-1030.
37. Grime J.P. Plant Strategies, Vegetation Processes and Ecosystem Properties 2001, Wiley, Chichester. 2nd ed.
38. Gross N., Kunstler G., Liancourt P., de Bello F., Suding K.N., Lavorel S. Linking individual response to biotic interactions with community structure: a trait-based framework. Funct. Ecol. 2009, 23:1167-1178.
39. Halloy S.R.P., Mark A.F. Comparative leaf morphology spectra of plant communities in New Zealand, the Andes and the European Alps. J. R. Soc. N. Z. 1996, 26:41-78.
40. Haussmann N.S., Boelhouwers J.C., McGeoch M.A. Fine scale variability in soil frost dynamics surrounding cushions of the dominant vascular plant species (Azorella selago) on sub-Antarctic Marion Island. Geografiska Ann. 2009, 91:257-268.
41. Haussmann N.S., McGeoch M.A., Boelhouwers J.C. Contrasting nurse plants and nurse rocks: the spatial distribution of seedlings of two sub-Antarctic species. Acta Oecologica 2010, 36:299-305.
42. Hedberg I., Hedberg O. Tropical-alpine life-forms of vascular plants. Oikos 1979, 33:297-307.
43. Herzog T. Die Pflantzenwelt des bolivischen Anden und irhes ostlichen 1923, Verlag, Vorlandes.
44. Holzapfel C., Tielbörger K., Parag H.A., Kigel J., Sternberg M. Annual plant-shrub interactions along an aridity gradient. Basic Appl. Ecol. 2006, 7:268-279.
45. Jacobsen D. Tropical high-altitude streams. Tropical Stream Ecology 2008, 219-256. Elsevier Science. D. Dudgeon (Ed.).
46. Jacobsen D., Dangles O. Environmental harshness and global richness patterns in glacier-fed streams. Glob. Ecol. Biogeogr. Early View 2012, 21:647-656.
47. Kessler M. The elevational gradient of Andean plant endemism: varying influences of taxon-specific traits and topography at different taxonomic levels. J. Biogeogr. 2002, 29:1159-1165.
48. Kikvidze Z., Pugnaire F.I., Brooker R.W., Choler P., Lortie C.J., Michalet R., Callaway R.M. Linking patterns and processes in alpine plant communities: a global study. Ecology 2005, 86:1395-1400.
49. Kikvidze Z., Michalet R., Brooker R.W., Lohengrin A.C., Lortie C.J., Pugnaire F.L., Callaway R.M. Climatic drivers of plant-plant interactions and diversity in alpine communities. Alp. Bot. 2011, 121:63-70.
50. Kleier C., Rundel P. Energy balance and temperature relations of Azorella compacta, a high-elevation cushion plant of the central Andes. Plant Biol. 2009, 11:351-358.
51. Kleier C., Lambrinos J.G. The importance of nurse associations for three tropical alpine life forms. Arctic Antarctic Alp. Res. 2005, 37:331-336.
52. Körner C. Alpine Plant Life: Functional Plant Ecology of High Mountain Ecosystems 2003, Springer-Verlag. 2nd ed.
53. Körner C. The use of 'altitude' in ecological research. Trends Ecol. Evol. 2007, 22:569-574.
54. Körner C. Coldest places on Earth with Angiosperm plant life. Alp. Bot. 2011, 121:73-78.
55. Le Roux P.C., McGeoch M.A. Spatial variation in plant interactions across a severity gradient in the sub-Antarctic. Oecologia 2008, 155:831-844.
56. Le Roux P.C., McGeoch M.A. Interaction intensity and importance along two stress gradients: adding shape to the stress-gradient hypothesis. Oecologia 2010, 162:733-745.
57. Letouzey R. Notice de la Carte Phytogéographique du Cameroun 1985, Institut de la Carte Internationale de la Végétation, Toulouse.
58. Leibold M.A., Holyoak M., Mouquet N., Amarasekare P., Chase J.M., Hoopes M.F., Holt R.D., Shurin J.B., Law R., Tilman D., Loreau M., Gonzalez A. The metacommunity concept: a framework for multi-scale community ecology. Ecol. Lett. 2004, 7:601-613.
59. Leuschner C. Timberline and alpine vegetation on the tropical and warm-temperate oceanic islands of the world: elevation, structure and floristics. Plant Ecol. 1996, 123:193-206.
60. Leuschner C. Are high elevations in tropical mountains arid environments for plants?. Ecology 2000, 81:1425-1436.
61. Leuschner C., Schulte M. Microclimatological investigations in the tropical alpine scrub of Maui Hawaii: evidence for a drought-induced alpine timberlin. Pacific Sci. 1991, 45:152-168.
62. Liancourt P., Callaway R.M., Michalet R. Stress tolerance and competitive-response ability determine the outcome of biotic interactions. Ecology 2005, 86:1611-1618.
63. Lipp C.C., Goldstein G., Meinzer F.C., Niemczura W. Freezing tolerance and avoidance in high elevation Hawaiian plants. Plant Cell Environ. 1994, 17:1035-1044.
64. Lortie C.J. Synthetic analysis of the stress-gradient hypothesis. Positive Plant Interactions and Community Dynamics 2010, 125-147. CRC Press. F.I. Pugnaire (Ed.).
65. Luteyn J.L. Páramos. A Checklist of Plant Diversity Geographical Distribution and Botanical Literature 1999, Garden Press, New York Bot.
66. Maestre F.T., Bautista S., Cortina J. Positive, negative and net effects in grass-shrub interactions in Mediterranean semiarid grasslands. Ecology 2003, 84:3186-3197.
67. Maestre F.T., Callaway R.M., Valladares F., Lortie C. Refining the stress-gradient hypothesis for competition and facilitation in plant communities. J. Ecol. 2009, 97:199-205.
68. Malkinson D., Tielbörger K. What does the stress-gradient hypothesis predict? Resolving the discrepancies. Oikos 2010, 119:1546-1552.
69. Mark A.F., Dickinson K.J.M., Hofstede R.G.M. Alpine vegetation, plant distribution, life forms, and environments in a perhumid New Zealand region: oceanic and tropical high mountain affinities. Arctic Antarctic Alp. Res. 2000, 32:240-254.
70. Matsuoka N. Temporal and spatial variations in periglacial soil movements on alpine crest slopes. Earth Surf. Process. Landforms 2005, 30:41-58.
71. Medina B.M.O., Ribeiro K.T., Scarano F.R. Plant-plant and plant-topography interactions on a rock outcrop at high altitude in southeastern Brazil. Biotropica 2006, 38:27-34.
72. Meinzer F.C., Goldstein G., Rundel P.W. Comparative water relations of tropical alpine plants. Tropic Alpine Environments: Plant form and Function 1994, 61-76. Cambridge Univ. Press. P.W. Rundel, A.P. Smith, F.C. Meinzer (Eds.).
73. Michalet R., Brooker R.W., Cavieres L.A., Kikvidze Z., Lortie C.J., Pugnaire F.I., Valiente-Banuet A., Callaway R.M. Do biotic interactions shape both sides of the humped-back model of species richness in plant communities?. Ecol. Lett. 2006, 9:767-773.
74. Michalet R., Xiao S., Touzard B., Smith D.S., Cavieres L.A., Callaway R.M., Whitham T.G. Phenotypic variation in nurse traits and community feedbacks define an alpine community. Ecol. Lett. 2011, 14:433-443.
75. Michel P., Lee W.G., During H.J., Cornelissen J.H.C. Species traits and their non-additive interactions control the water economy of bryophyte cushions. J. Ecol. 2012, 100:222-231.
76. Miller G.A., Silander J.A. Control of the distribution of giant rosette species of Puya (Bromeliaceae) in the Ecuadorian Paramos. Biotropica 1991, 23:134-143.
77. Miriti M.A. Ontogenetic shift from facilitation to competition in a desert shrub. J. Ecol. 2006, 94:973-979.
78. Mitchell M.G.E., Cahill J.F., Hik D.S. Plant interactions are unimportant in a subarctic-alpine plant community. Ecology 2009, 90:2360-2367.
79. Mizuno K. Succession processes of alpine vegetation in response to glacial fluctuations of Tyndall Glacier, Mt. Kenya, Kenya. Arctic Antarctic Alp. Res. 1998, 30:340-348.
80. Molau U. Mountain biodiversity patterns at low and high latitudes. Ambio 2004, 13:24-28. (special report).
81. Monasterio M. El Páramo Desértico en el altiandino de Venezuela. El Medio Ambiente Páramo 1979, 117-146. CIET-IVIC/MAB-UNESCO. M.L. Salgado-Labouriau (Ed.).
82. Nagy L., Grabherr G. The Biology of Alpine Habitats 2009, Oxford Univ. Press.
83. Patty L., Halloy S.R.P., Hiltbrunner E., Körner C. Biomass allocation in herbaceous plants under grazing impact in the high semi-arid Andes. Flora 2010, 205:695-703.
84. Pérez F.L. Needle-ice activity and the distribution of stem-rosette species in a Venezuelan Páramo. Arctic Alp. Res. 1987, 19:135-153.
85. Pérez F.L. Soil moisture and the upper altitudinal limit of giant paramo rosette. J. Biogeogr. 1987, 14:173-186.
86. Pérez F.L. Some effects of giant Andean stem-rosettes on ground microclimate, and their ecological significance. Int. J. Biometeorol. 1989, 33:131-135.
87. Pérez F.L. Influence of substrate on the distribution of the Hawaiian Silversword (Argyroxiphium sandwicense DC.) in Haleakala (Maui HI). Geomorphology 2003, 55:173-202.
88. Ramsay P.M., Oxley E.R.B. The growth form composition of plant communities in the Ecuadorian páramos. Plant Ecol. 1997, 131:173-192.
89. Rada F., Garcia-Nunez C., Boero C., Gallardo M., Hilal M., Gonzalez J., Prado F., Liberman-Cruz M., Azocar A. Low temperature resistance in Polylepis tarapacana, a tree growing at the highest altitudes in the world. Plant Cell Environ. 2001, 24:377-381.
90. Reid A.M., Lamarque L.J., Lortie C.J. A systematic review of the recent ecological literature on cushion plants: champions of plant facilitation. Web Ecol. 2010, 10:44-49.
91. Rundel P.W. Tropical alpine climates. Tropic Alpine Environments: Plant Form and Function 1994, 21-44. Cambridge Univ. Press. P.W. Rundel, A.P. Smith, F.C. Meinzer (Eds.).
92. Rundel P.W., Smith A.P., Meinzer F.C. Tropical Alpine Environments: Plant Form and Function 1994, Cambridge Univ. Press.
93. Safford H.D. Brazilian páramos. I. An introduction to the physical environment and vegetation of the campos de altitude. J. Biogeogr. 1999, 26:693-712.
94. Sakai A., Larcher W. Frost Survival of Plants: Responses and Adaptation to Freezing Stress 1987, Springer-Verlag, Berlin.
95. Sarmiento L., Llambí L.D., Escalona A., Marquez N. Vegetation patterns, regeneration rates and divergence in an old-field succession of the high tropical Andes. Plant Ecol. 2003, 166:63-74.
96. Schiffers K., Tielbörger K. Ontogenetic shifts in interactions among annual plants. J. Ecol. 2006, 94:336-341.
97. Seifan M., Seifan T., Ariza C., Tielbörger K. Facilitating an importance index. J. Ecol. 2010, 98:356-361.
98. Sgorbati S., Labra M., Grugni E., Barcaccia G., Galasso G., Boni U., Mucciarelli M., Citterio S., Benavides Iramategui A., Venero Gonzales L., Scannerini S. A survey of genetic diversity and reproductive biology of Puya raimondii (Bromeliaceae), the endangered queen of the Andes. Plant Biol. 2004, 6:222-230.
99. Simpson B. Glacial migration of plants: island biogeographical evidence. Science 1974, 185:698-700.
100. Sklenář P. Presence of cushion plants increases community diversity in the high equatorial Andes. Flora 2009, 204:270-277.
101. Sklenář P., Duskova E., Balslev H. Tropical and temperate: evolutionary history of páramo flora. Bot. Rev. 2011, 77:71-108.
102. Sklenář P., Laegaard S. Rain-shadow in the high Andes of Ecuador evidenced by paramo vegetation. Arctic Antarctic Alp. Res. 2003, 35:8-17.
103. Smith A.P. Notes on wind-related growth patterns of pdramo plants in Venezuela. Biotropica 1972, 4:10-16.
104. Smith A.P. The paradox of plant height in an Andean giant rosette species. J. Ecol. 1980, 68:63-73.
105. Smith A.P. Growth and population dynamics of Espeletia (Compositae) in the Venezuelan Andes. Smithson. Contrib. Bot. 1981, 48:1-45.
106. Smith A.P. Postdispersal parent-offspring conflict in plants: antecedent and hypothesis from the Andes. Am. Nat. 1984, 123:354-370.
107. Smith A.P. Introduction to tropical alpine vegetation. Tropic Alpine Environments: Plant Form and Function 1994, 1-20. Cambridge Univ. Press. P.W. Rundel, A.P. Smith, F.C. Meinzer (Eds.).
108. Smith A.P., Young T.P. Tropical alpine plant ecology. Ann. Rev. Ecol. Syst. 1987, 18:137-158.
109. Smith A.P., Young T.P. Population biology of Senecio keniodendron (Asteraceae), an Afroalpine giant rosette plant. Tropic Alpine Environments: Plant Form and Function 1994, 273-294. Cambridge Univ. Press. P.W. Rundel, A.P. Smith, F.C. Meinzer (Eds.).
110. Smith T.J., McNamara J.P., Flores A.N., Gribb M.M., Aishlin P.S., Benner S.G. Small soil storage capacity limits benefit of winter snowpack to upland vegetation. Hydro. Process. 2011, 25:3858-3865.
111. Soliveres S.L., DeSoto L., Maestre F.T., Olano J.M. Spatio-temporal heterogeneity in abiotic factors modulates multiple ontogenetic shifts between competition and facilitation. Perspect. Plant Ecol. Evol. Syst. 2010, 12:227-234.
112. Squeo F.A., Rada F., Garcia C., Ponce M., Rojas A., Azocar A. Cold resistance mechanisms in high desert Andean plants. Oecologia 1996, 105:552-555.
113. Stocks G., Seales L., Paniagua F., Maehr E., Bruna E.M. The geographical and institutional distribution of ecological research in the tropics. Biotropica 2008, 40:397-404.
114. Tilman D. Resource Competition and Community Structure 1982, Princeton University Press.
115. Turner R.M., Alcorn S.M., Olin G., Booth J.A. The influence of shade, soil and water on saguaro seedling establishment. Bot. Gazette 1966, 127:95-102.
116. Valiente-Banuet A., Verdu M. Temporal shifts from facilitation to competition occur between closely related taxa. J. Ecol. 2008, 96:489-494.
117. van der Hammen T., Cleef A.M. Development of the high Andean páramo flora and vegetation. High Altitude Tropical Biogeography 1986, 153-201. Oxford University Press. F. Vuilleumier, M. Monasterio (Eds.).
118. Venn S.E., Morgan J.W., Green P.T. Do facilitative interactions with neighboring plants assist the growth of seedlings at high altitudes in alpine Australia?. Arctic Antarctic Alp. Res. 2009, 41:381-387.
119. Violle C., Enquist B.J., McGill B.J., Jiang L., Albert C.H., Hulschof C., Jung V., Messier J. The return of the variance: intraspecific variability in community ecology. Trends Ecol. Evol. 2012, 27:244-252.
120. Violle C., Navas M.L., Vile D., Kazakou E., Fortunel C., Hummel I., Garnier E. Let the concept of trait be functional!. Oikos 2007, 116:882-892.
121. Wipf S., Rixen C. A review of snow manipulation experiments in arctic and alpine tundra ecosystems. Polar Res. 2010, 29:95-109.
122. White F. The Vegetation of Africa 1983, UNESCO.
123. Young T.P., Peacock M.M. Giant Senecios and alpine vegetation of Mount Kenya. J. Ecol. 1992, 80:141-148.
124. Young T.P., van Arden Robe S. Microenvironmental role of a secreted aqueous solution in the afro-alpine plant Lobelia keniensis. Biotropica 1986, 18:267-269.