Water Freedom System

Survive Global Water Shortages

Get Instant Access

Fig. 3.34 Leaf-cutter ants

Leaf-cutter ants are a special case because they collect an enormous amount of plant biomass and carry it into complicated underground chamber systems where they cultivate fungi. Some quantitative data are compiled in Table 3.3. The loss of foliage by the host plants of up to 40% can reduce their fitness. However, there is also compensatory feedback. Leaf-cutter ants prefer to collect leaf pieces from the upper canopy. Partial defoliation causes an increase in the frequency and variability of light flecks and may result in higher rates of photosynthesis due to increased light penetration and incident irradiance on the remaining parts of tree crowns. Thus, herbivory by leaf-cutter ants appears to have little effect on whole forest canopy photosynthesis although it may considerably reduce photosynthesis locally. The effects on nutrient flow in the forests are patchy because the ants, Atta colombica as the species of the case study of Wirth et al. (2003), bury the nitrogen rich exhausted fungal substrate or refuse from their fungi gardens in large refuse chambers below the fungus chambers of their nests at a depth of 7 m below the surface and only partially on the soil surface. Only deep rooting trees may have access to the former but fine roots of nearby plants may penetrate the latter. The refuse is enriched in nitrogen because the ants prefer to collect the more N-rich young leaves and use more the carbon than the nitrogen. The carbon/nitrogen ratios are 22 in canopy foliage and 36 in normal leaf litter, 21 in the leaf harvest of the ants and only 16 in the refuse dump from the ant's fungi gardens. In the study area of Wirth et al. (2003) on Barro Colorado Island, Panamá, in locations covering less than 0.5% of the area populated by leaf-cutting ants nitrogen flux is therefore about 20 - 30 times higher than in the rest of the forest. Hence, while a large scale benefit of plant nutrition from leaf-cutter ants is debatable local positive effects on plant growth and fitness are evident. Nutrient Partitioning

Different partitioning of inorganic nitrogen assimilation between the roots and shoots of trees is observed in pioneer and mature phase trees of tropical forests. In gaps the mineralization of a large mass of fresh litter, e.g. from fallen trees, may lead to higher availability of NO--N (not NH+-N) and PO4-P (Denslow et al. 1998). Thus, rapidly growing pioneer or colonizing tree species, which are exposed to high irradiation, exhibit a large capacity to assimilate nitrate in their leaves, where light energy can be directly used in photosynthetic nitrate reduction (Aidar et al. 2003). Partitioning of NO--assimilation between roots and shoots is strongly related with average daily photosynthetically active radiation rather than the availability of NO-in the soil (Stewart et al. 1992). Leaves of shaded species have low levels of nitrate reductase and show little capacity to utilize nitrate, even when it was readily available, and primarily assimilate ammonia (Stewart et al. 1988, 1990; Fredeen et al. 1991; Fredeen and Field 1992; Denslow et al. 1998). Flushing of New Leaves and Longevity of Mature Leaves Related to Nutrient Budgets

An interesting phenomenon, which may also be related to nutrient budgets is leaf flushing. New leaves and shoots expand from their buds very rapidly to attain a size close to that of mature leaves, much before they reach their final rigidity and pigmentation. In fact they hang down from the branches as if wilted, and often are coloured brightly yellow or red (Fig. 3.35). The development of chloroplasts and the photosynthetic apparatus is delayed which are both particularly nitrogen-demanding. This can be considered to be an adaptation to conditions of high fungal and herbivore damage to the expanding leaves. Damage may be 100 times higher to young than to mature leaves. Mature leaves are better protected (Kursar and Co-ley 1992a,b; Schlindwein et al. 2006). Costs of damage to the newly flushed leaves remains low since not so many resources have been invested in them. Resource allocation to leaves becomes beneficial when they mature and establish photosynthetic productivity in return. Delayed greening is observed in many species (Kursar and Coley 1992b; Miyazawa and Terashima 2001) and occurs mainly in shade tolerant species and not in gap-requiring species. In the shade a late development of photosynthesis is less disadvantageous than in high light (Kursar and Coley 1992b). It would be interesting to know if the bright colour of freshly flushed leaves even functions in attracting herbivores to these "cheap" leaves, thus protecting the "expensive" mature leaves. In a tropical dry-deciduous forest and a dry-thorn forest in India, phenological strategies have also been observed in relation to leaf flushing. Flushing occurs in the dry season and reaches a peak before the onset of the rains. Herbivorous insects emerge with the rains and attain a peak biomass during the wet months, so that early leaf flushing and maturation provides protection (Murali and Sukumar 1993).

Nutrient availability also affects the structure and longevity of leaves of forest trees. Leaf longevity may vary in different tropical forest tree species from about

Fig. 3.35A,B Leaf-flushing. A in a mango tree, B in Brownea sp.

18 months to several years (Richards 1996). It is highly plastic and can respond to light (Osada et al. 2001). Small leathery leaves ("scleromorphic microphylls") are developed on infertile soils due to N- but mainly P-deficiency (Medina and Cuevas 1989; Medina et al. 1990). Such leaves are more durable and better protected from herbivory (Choong et al. 1992) than large, thin leaves. Thus, nutrient investment in leaf structure provides a return in the form of photosynthetic products for a longer period of time. Deciduous and evergreen species coexist in tropical dry forests. They differ greatly in their investments of resources for leaf construction and maintenance. In deciduous species, with roots occurring under relatively nutrient-rich conditions, leaves can have a potentially high nitrogen-use efficiency (CO2-assimilation related to leaf N-content; see Sect. 4.1.2). Conversely, in evergreen species with lower nitrogen-use efficiency, the long residence time of nitrogen is favourable because roots occur in nutrient-poor soil microhabitats (Sobrado 1991). Both deciduous and evergreen species preserve nitrogen resources. Reserves of nitrogen are maintained in the twigs in drought-deciduous species and in the older leaves in evergreen species, providing some nitrogen for the reconstruction of new leaves following drought and during leaf exchange respectively (Sobrado 1995). In conclusion, plant species obviously allocate resources either to obtain a high photosynthetic assimilation rate from large and fragile leaves for a brief time or to provide a resistant physical structure which results in a lower rate of CO2 assimilation over a longer time (Reich et al. 1991). Thus, mineral nutrition influences the lifespan of leaves.


Aidar MPM, Schmidt S, Moss G, Stewart GR, Joly CA (2003) Nitrogen use strategies of neotropical rainforest trees in threatened Atlantic Forest. Plant Cell Environ 26:389-399 Beard JS (1946) The natural vegetation of Trinidad. Oxford Forestry Memoirs, No 20. Oxford

University Press, Oxford Beard JS (1955) The classification of tropical American vegetation types. Ecology 36:89-100 Beck E, Lüttge U (1990) Streß bei Pflanzen. Biol Unserer Zeit 20:237-244 Bell G, Lechowicz MJ, Appenzeller A, Chandler M, DeBlois E, Jackson L, Mackenzie B, Preziosi R, Schallenberg M, Tinker N (1993) The spatial structure of the physical environment. Oe-cologia 96:114-121

Bereau M, Louisanna E, Garbaye J (2004) Mycorrhizal symbiosis in the tropical rainforest of French Guiana and its potential contribution to tree regeneration and growth. In: Gourlet-Fleury S, Guehl J-M, Laroussinie O (eds) Ecology and management of a neotropical rainforest. Elsevier, Amsterdam, pp 114-119 Bongers F, Meer PJ van der, Thery M (2001) Scales of ambient light variation. In: Bongers F, Charles-Dominique P, Forget P-M, Thery M (eds) Nouragues. Dynamics and plant animal interactions in a neotropical rainforest. Kluwer Academic Publishers, Dordrecht, pp 19-29 Booth RE, Grime JP (2003) Effects of genetic impoverishment on plant community diversity. J Ecol 91:721-730

Booy G, Hendriks RJJ, Smulders MJM, Groenendael JM van, Vosman B (2000) Genetic diversity and the survival ofpopulations. Plant Biol 2:379-395 Brearley FQ, Press MC, Scholes JD (2003) Nutrients obtained from leaf litter can improve the growth of dipterocarp seedlings. New Phytol 160:101-110 Buchmann N, Kao W-Y, Ehleringer JR (1996) Carbon dioxide concentrations within forest canopies

- variation with time, stand culture, and vegetation type. Global Change Biol 2:421-432 Buchmann N, Bonal D, Barigah TS, Guehl J-M, Ehleringer JR (2004) Insights into the carbon dynamics of tropical primary rainforests using stable carbon isotope analyses. In: Gourlet-Fleury S, Guehl J-M, Laroussinie O (eds) Ecology and management of a neotropical rainforest. Elsevier, Amsterdam, pp 95-113 Campbell BD, Grime JP, Mackey JML, Jalili A (1991) The quest for a mechanistic understanding of resource competition in plant communities: the role of experiments. Funct Ecol 5:241-253 Chazdon RL, Fetcher N (1984) Light environments of tropical rainforests. In: Medina E, Mooney HA, Vazquez-Yanes C (eds) Physiological ecology of plants in the wet tropics. Dr W Junk, The Hague, pp 27-50

Choong MF, Lucas PW, Ong JSY, Pereira B, Tan HTW, Turner IM (1992) Leaf fracture toughness and sclerophylly:their correlations and ecological implications. New Phytol 121:597-610 Chuyong GB, Newbery DM, Songwe NC (2000) Litter nutrients and retranslocation in a central

African rain forest dominated by ectomycorrhizal trees. New Phytol 148:493-510 Clements FE (1936) Nature and structure of the climax. J Ecol 24:252-284 Crook MJ, Ennos AR, Banks JR (1997) The function of buttress roots: a comparative study of the anchorage systems of buttressed (Aglaia and Nephelium ramboutan species) and non-buttressed (Mallotus wraja) tropical trees. J Exp Bot 48:1703-1716 Dalling JW, Hubbell SP, Silvera K (1998) Seed dispersal, seedling establishment and gap partitioning among tropical pioneer trees. J Ecol 86:674-689 Davidson DW, Epstein WW (1989) Epiphytic associations with ants. In: Lüttge U (ed) Vascular plants as epiphytes. Evolution and ecophysiology. Ecological Studies, vol 76. Springer, Berlin Heidelberg New York, pp 200-233 Davies SJ, Palmiotto PA, Ashton PS, Lee HS, Lafrankie JV (1998) Comparative ecology of 11 sympatric species of Macaranga in Borneo: tree distribution in relation to horizontal and vertical resource heterogeneity. J Ecol 86:662-673 Denslow JS, Ellison AM, Sanford RE (1998) Treefall gap size effects on above- and below-ground processes in a tropical wet forest. J Ecol 86:597-609

Doley D, Yates DJ, Unwin GL (1987) Photosynthesis in an Australian rainforest tree, Argyroden-dron peralatum, during the rapid development and relief of water deficits in the dry season. Oecologia 74:441-449

Domenach A-M, Roggy J-C, Molino J-F, Marechal J, Sabatier D, Prévost M-F (2004) Diversity of the leguminous tree Rhizobium associations and role of the nitrogen fixation on the stability of the rainforest in French Guiana. In: Gouret-Fleury S, Guehl JM, Laroussinie O (eds) Ecology and management of a neotropical rainforest. Elsevier, Amsterdam, pp 120-143 Duarte Rocha CF, Godoy Bergallo H (1992) Bigger ant colonies reduce herbivory and herbivore residence time on leaves of an ant-plant: Azteca muelleri vs. Coelomera ruficornis on Cecropia pachystachya. Oecologia 91:249-252 Esteves FA (1998) Considerations on the ecology of wetlands, with emphasis on Brazilian flood-plain ecosystems. In: Scarano FR, Franco AC (eds) Ecophysiological strategies of xerophytic and amphibious plants in the neotropics. Oecologia Brasiliensis, vol IV, Universidade Federal do Rio de Janeiro, Rio de Janeiro, pp 111-135 Fernandez MD, Pieters A, Donoso C, Herrera C, Tezara W, Rengifo E, Herrera A (1999) Seasonal changes in photosynthesis of trees in the flooded forest of the Mapire river. Tree Physiol 19:7985

Fischer RC, Wanek W, Richter A, Mayer V (2003) Do ants feed plants? A 15N labelling study of nitrogen fluxes from ants to plants in the mutualism of Pheidole and Piper. J. Ecol 91:126-134 Fredeen AL, Field CB (1992) Ammonium and nitrate uptake in gap generalist and understory species of the genus Piper. Oecologia 92:207-214 Fredeen AL, Griffin K, Field CB (1991) Effects of light quantity and quality and soil nitrogen status on nitrate reductase activity in rainforest species of the genus Piper. Oecologia 86:441-446 Gehrig H, Gaussmann O, Marx H, Schwarzott D, Kluge M (2001) Molecular phylogeny of the genus Kalanchoë (Crassulaceae) inferred from nucleotide sequences of the IST-1 and IST-2 regions. Plant Sci 160:827-835 Grime JP, Mackey JML, Hillier SH, Read DJ (1987) Floristic diversity in a model system using experimental microsoms. Nature 328:420-422 Guehl J-M, Bonal D, Ferhi A, Barigah TS, Farquhar G, Granier A (2004) Community-level diversity of carbon-water relations in rainforest trees. In: Gourlet-Fleury S, Guehl J-M, Laroussinie O (eds) Ecology and management of a neotropical rainforest. Elsevier-Amsterdam, pp 75-94 Herz H, Beyschlag W, Hölldobler B (2006) Herbivory rate of leaf-cutting ants in a tropical moist forest in Panama at the population and ecosystem scales. Biotropica (in press) Jacobs M (1988) The tropical rain forest. Springer, Berlin Heidelberg New York Junk WJ (1997) Distribution and size of neotropical floodplains. In: Junk WJ (ed) The Central Amazon floodplain. Ecological Studies vol 126. Springer, Berlin Heidelberg New York, pp 12-16

Junk WJ, Furch K (1985) The physical and chemical properties of Amazonian waters and their relationships with biota. In: Prance GT, Lovejoy TE (eds) Amazonia. Pergamon, Oxford, p 7 Kitayama K, Aiba S-I (2002) Ecosystem structure and productivity of tropical rainforests along al-titudinal gradients with contrasting soil phosphorus pools on Mount Kinabalu, Borneo. J Ecol 90:37-51

Kleunen M van, Fischer M (2005) Constraints on the evolution of adaptive phenotypic plasticity in plants. New Phytol 166:49-60 Kratochwil A (1998) Biodiversity in ecosystems. Atti dei Convegni Lincei 145:23-62 Kursar TA, Coley PD (1992a) Delayed development of the photosynthetic apparatus in tropical rain forest species. Funct Ecol 6:411-422 Kursar TA, Coley PD (1992b) The consequences of delayed greening during leaf development for light absorption and light use efficiency Plant Cell Environ 15:901-909 Larcher W (1987) Streß bei Pflanzen. Naturwissenschaften 74:158-167

Levin SA, Muller-Landau HC (2001) The emergence of diversity in plant communities. CR Acad

Sci Paris Sci de la Vie 323:129-139 Levitt J (1980) Responses of plants to environmental stresses, vol I. Academic Press, New York

Lobo PC, Joly CA (1998) Tolerance to hypoxia and anoxia in neotropical tree species. In: Scarano FR, Franco AC (eds) Ecophysiological strategies of xerophytic and amphibious plants in the neotropics. Oecologia Brasiliensis, vol IV, Universidade Federal do Rio de Janeiro, Rio de Janeiro, pp 111-135

Löscher HW, Oberbauer SF, Gholz HL, Clark DB (2003) Environmental controls on net ecosystem-level carbon exchange and productivity in a Central American tropical wet forest. Global Change Biol 9:396-412

Lüttge U (1995) Ecophysiological basis of the diversity of tropical plants: the example of the genus Clusia. In: Heinen HD, San José JJ, Caballero-Arias H (eds) Nature and human ecology in the neotropics. Sci Guaianae 5:23-26 Lüttge U (2005) Genotypes-phenotypes-ecotypes: relations to Crassulacean acid metabolism.

Nova Acta Leopoldina NF 92/342, pp 177-193 Lüttge U (2007) Physiological ecology. In: Lüttge U (ed) Clusia: a woody neotropical genus of remarkable plasticity and diversity. Ecol Studies vol. 194. Springer, Berlin Heidelberg NewYork, pp 187-234

Manrubia SC, Solé RV (1996) Self-organized criticality in rainforest dynamics. Chaos, Solitons and Fractals 7:523-541

Massey FP, Massey K, Press MC, Hartley SE (2006) Neighbourhood composition determines growth, architecture and herbivory in tropical rain forest tree seedlings. J Ecol 94:646-655 Mattheck C (1992) Design in der Natur. Der Baum als Lehrmeister. Rombach Freiburg i. Breisgau Medina E (1983) Adaptations of tropical trees to moisture stress. In: Golley FB (ed) Tropical rain forest ecosystems, A. Structure and function. Elsevier, Amsterdam, pp 225-237 Medina E (1986) Forests, savannas and montane tropical environment. In: Baker NR, Long SP

(eds) Photosynthesis in contrasting environments. Elsevier Amsterdam, pp 139-171 Medina E, Cuevas E (1989) Patterns of nutrient accumulation and release in Amazonian forests of the upper Rio Negro basin. In: Proctor J (ed) Mineral nutrients in tropical forest and savanna ecosystems. Blackwell Oxford, pp 217-240 Medina E, Cuevas E (1994) Mineral nutrition:humid tropical forests. Prog Bot 55:115-129 Medina E, García V, Cuevas E (1990) Sclerophylly and oligotrophic environments: relationships between leaf structure, mineral nutrient content, and drought resistance in tropical rain forests of the upper Rio Negro region. Biotropica 22:51-64 Meer PJ van der, Bongers F (1996) Patterns of tree-fall and branch-fall in a tropical rain forest in

French Guiana. J Ecol 84:19-29 Miyazawa S-I, Terashima I (2001) Slow development of leaf photosynthesis in an evergreen broad-leaved tree, Castanopsis sieboldii: relationships between leaf anatomical characteristics and photosynthesis and photosynthetic rate. Plant Cell Environ 24:279-291 Morawetz W, Wallnöfer B (1992) Die Ameisenpflanzen entlang eines Transekts durch das Sira-Gebirge (Peruanisches Amazonien) und ihre ökologische Stellung im Regenwald. Dtsch Ges Tropenökologie, Jahrestagung Bonn Morawetz W, Henzl M, Wallnöfer B (1992) Tree killing by herbicide producing ants for the establishment of pure Tococa occidentalis populations in the Peruvian Amazon. Biodivers Conserv 1:19-33

Murali KS, Sukumar R (1993) Leaf flushing phenology and herbivory in a tropical dry deciduous forest, southern India. Oecologia 94:114-119 Myers N, Mittermeier RA, Mittermeier CG, Fonseca GAB, Kent J (2000) Biodiversity hotspots for conservation priorities. Nature 403:853-858 Newell EA, McDonald EP, Strain BR, Denslow JS (1993) Photosynthetic responses of Miconia species to canopy openings in a lowland tropical rainforest. Oecologia 94:49-56 Nickol MG (1992) Untersuchungen der Myrmekodomatien von Tococa guianensis (Melastomat-

aceae). Dtsch Ges Tropenökologie, Jahrestagung Bonn Noss RF (1983) A regional landscape approach to maintain diversity. BioScience 33:700-706 Orians GH (1982) The influence of tree-fall in tropical forest on tree species richness. Trop Ecol 23:255-279

Osada N, Takeda H, Furukawa A, Awang M (2001) Leaf dynamics and maintenance of tree crowns in a Malaysian rain forest stand. J Ecol 89:774-782 Palmiotto PA, Davies SJ, Vogt KA, Ashton MS, Vogt DJ, Ashton PS (2004) Soil-related habitat specialization in dipterocarp rain forest tree species in Borneo. J Ecol 92:609-623 Phillips OL, Vargas PN, Monteagudo AL, Cruz AP, Zans MEC, Sánchez WG, Yli-HallaM, Rose S (2003) Habitat association among Amazonian tree species: a landscape-scale approach. J Ecol 91:757-775

Piedade MTF, Long SP, Junk WJ (1994) Leaf and canopy photosynthetic CO2 uptake of a stand of Echinochloa polystachia on the Central Amazon floodplain. Are the high potential rates associated with the C4 syndrome realized under the near-optimal conditions provided by this exceptional natural habitat? Oecologia 97:193-201 Pimenta JA, Bianchini E, Medri ME (1998) Adaptations to flooding by tropical trees: morphological and anatomical modifications. In: Scarano FR, Franco AC (eds) Ecophysiological strategies of xerophytic and amphibious plants in the neotropics. Oecologia Brasiliensis, vol IV, Universidade Federal do Rio de Janeiro, Rio de Janeiro, pp 157-176 Pons TL, Perreijn K, Kessel C van, Werger MJA (2007) Symbiotic nitrogen fixation in a tropical rainforest: 15N natural abundance measurements supported by experimental isotopic enrichment. New Phytol 173:154-167 Reich PB, Uhl C, Walters MB, Ellsworth DS (1991) Leaf life span as a determinant of leaf structure and function among 23 amazonian tree species. Oecologia 86:16-24 Reichholf JH (1994) Biodiversity. Why are there so many different species? Universitas 1994/1:4251

Remmert H (1985) Was geschieht im Klimax-Stadium? Ökologisches Gleichgewicht durch Mosaik aus desynchronen Zyklen. Naturwissenschaften 72:505-512 Remmert H (1991) The mosaic cycle of ecosystems. Ecological Studies, vol 85. Springer, Berlin Heidelberg New York

Richards PW (1996) The tropical rain forest. An ecological study, 2nd edn. Cambridge Univ Press, Cambridge

Santiago LS, Mulkey SS (2005) Leaf productivity along a precipitation gradient in lowland

Panama: patterns from leaf to ecosystem Trees 19:349-356 Sarmiento G (1984) The ecology of neotropical savannas. Harvard University Press, Cambridge Schlindwein CCD, Fett-Neto AG, Dillenburg LR (2006) Chemical and mechanical changes during leaf expansion of four woody species of a dry restinga woodland. Plant Biol 8:430-438 Schuster P (1998) Evolution in molekularer Auflösung. Ber u Abh Berlin-Brandenb Akad Wiss 6:187-215

Selye H (1973) The evolution of the stress concept. Am Sci 61:693-699

Silver WL (1994) Is nutrient availability related to plant nutrient use in humid tropical forests? Oecologia 98:336-343

Simone O de, Haase K, Müller E, Junk WJ, Gonsior G, Schmidt W (2002) Funct Plant Biol 29:1025-1035

Simone O de, Haase K, Müller E, Junk WJ, Hartmann K, Schreiber L, Schmidt W (2003a) Apoplasmic barriers and oxygen transport properties by hypodermal cell walls in roots from four Amazonian tree species. Plant Physiol 132:206-217 Simone O de, Müller E, Junk WJ, Richau K, Schmidt W (2003b) Iron distribution in three central Amazon tree species from white water-inundation areas (várza) subjected to different iron regimes. Trees 17:535-541 Sobrado MA (1991) Cost-benefit relationships in deciduous and evergreen leaves of tropical dry forest species. Func Ecol 5:608-616 Sobrado MA (1995) Seasonal differences in nitrogen storage in deciduous and evergreen species of a tropical dry forest. Biol Plant 37:291-295 Solbrig OT (1994) Plant traits and adaptive strategies: their roles in ecosystem function. In: Schulze E-D, Mooney HA (eds) Biodiversity and ecosystem function. Ecological Studies 99. Springer, Berlin Heidelberg New York, pp 97-116

Solé RV, Manrubia SC (1995a) Self-similarity in rain forests: evidence for a critical state. Phys Rev E 51:6250-6253

Solé RV, Manrubia SC (1995b) Are rainforests self-organized in a critical state? J Theor Biol 173:31-40

Solé RV, Manrubia SC, Luque B (1994) Multifractals in rainforest ecosystems: modelling and simulations. In: Novak NM (ed) Fractals in the natural and applied sciences. Elsevier, Amsterdam, pp 397-407

Souza Moreira FM de, Silva MF da, Faria SM de (1992) Occurrence of nodulation in legume species in the Amazon region of Brazil. New Phytol 121:563-570 Stewart GR, Hegarty EE, Specht RL (1988) Inorganic nitrogen assimilation in plants of Australian rainforest communities. Physiol Plant 74:26-33 Stewart GR, Gracia CA, Hegarty EE, Specht RL (1990) Nitrate reductase activity and chlorophyll content in sun leaves of subtropical Australian cloud-forest (rainforest) and open-forest communities. Oecologia 82:544-551 Stewart GR, Joly CA, Smirnoff N (1992) Partitioning of inorganic nitrogen assimilation between the roots and shoots of cerrado and forest trees of contrasting plant communities of South East Brasil. Oecologia 91:511-517 Sultan SE, Bazzaz FA (1993) Phenotypic plasticity in Polygonum persicaria. I. Diversity and uniformity in genotypic norms of reaction to light. Evolution 47:1009-1031 Talbott LD, Rahveh E, Zeiger E (2003) Relative humidity is a key factor in the acclimation of the stomatal response to CO2. J Exp Bot 54:2141-2147 Tilman D (1982) Resource competition and community structure. Princeton Univ. Press, Princeton Torquebiau EF (1988) Phtosynthetically active radiation environment, patch dynamics and architecture in a tropical rainforest in Sumatra. Aust J Plant Physiol 15:327-342 Valencia R, Foster RB, Villa G, Condit R, Svenning JC, Hernández C, Romoleroux K, Losos E, Magárd E, Balsev H (2004) Tree species distributions and local habitat variation in the Amazon: large forest plot in eastern Ecuador. J Ecol 92:214-229 Vareschi V (1980) Vegetationsökologie der Tropen. Ulmer, Stuttgart Walter H (1973) Vegetationszonen und Klima. Ulmer, Stuttgart

Walter H, Breckle S-W (1984) Ökologie der Erde, vol 2. Spezielle Ökologie der tropischen und subtropischen Zonen. G Fischer, Stuttgart Watt AS (1947) Pattern and process in the plant community. J Ecol 35:1-22 Webber BL, Abaloz BA, Woodrow IE (2006) Myrmecophilic food body production in the under-storey tree, Ryparosa kurrangii (Achariaceae), a rare Australian rain forest taxon. New Phytol 173:250-263

West-Eberhard MJ (1986) Alternative adaptations, speciation, and phylogeny (a review). Proc Natl

Acad Sci USA 83:1388-1392 West-Eberhard MJ (1989) Phenotypic plasticity and the origins of diversity. Annu Rev Ecol Syst 20:249-278

West-Eberhard MJ (2003) Developmental plasticity and evolution. Oxford University Press, Oxford

Whitmore TC (1990) An introduction to tropical rain forests. Oxford University Press, Oxford Whittaker RH (1975) Communities and ecosystems, 2nd edn. Macmillan, New York Wirth R, Herz H, Ryel RJ, Beyschlag W, Hölldobler B (2003) Herbivory of leaf-cutting ants. A case study on Atta colombica in the tropical rainforest of Panamá. Ecological Studies, vol. 164. Springer, Berlin Heidelberg New York

Was this article helpful?

0 0
Renewable Energy 101

Renewable Energy 101

Renewable energy is energy that is generated from sunlight, rain, tides, geothermal heat and wind. These sources are naturally and constantly replenished, which is why they are deemed as renewable. The usage of renewable energy sources is very important when considering the sustainability of the existing energy usage of the world. While there is currently an abundance of non-renewable energy sources, such as nuclear fuels, these energy sources are depleting. In addition to being a non-renewable supply, the non-renewable energy sources release emissions into the air, which has an adverse effect on the environment.

Get My Free Ebook

Post a comment