Leaf-Litter Arthropods in Restored Forests in the Colombian Andes: A Comparison Between Secondary Forest and Tree Plantations Gustavo H. Kattan,1 Darı´o Correa,1,2 Federico Escobar,1,3 and Claudia Medina1,4 Abstract Tree monocultures of native and exotic species are frequently used as tools to catalyze forest recovery throughout the tropics. Although plantations may rapidly develop a canopy cover, they need to be evaluated as habitat for other organisms. We compared samples of leaf-litter arthropods from two elevations in restored forest in the Colombian Andes. At the upper elevation (2,430 m), we compared native Andean alder (Alnus acuminata) plantation and secondary forest, and at the lower elevation (1,900 m) exotic Chinese ash (Fraxinus chinensis) plantation and secondary forest. Samples were obtained in two periods, March–April and September 1995. Species richness and abundance of arthropods were highest in secondary forest at the lower elevation. There were no differences in richness between both plantations and high-elevation forest. Arthropod richness and abundance increased in the second sampling period in both secondary

Introduction Many restoration efforts in the tropics have used monospecific tree plantations of both native and exotic species to accelerate forest recovery (Haggar et al. 1997; Lugo 1997; Parrotta et al. 1997; Powers et al. 1997; Ewel & Putz 2004). Although tree plantations may rapidly produce a canopy cover, particularly if fast-growing species are used, the resulting forest may not resemble a native ecosystem. If the objective is to obtain vegetative cover for soil stabilization and erosion control, then plantations may be adequate (Ewel & Putz 2004). Ideally, however, ecological restoration projects for conservation purposes should aim not only to restore tree cover but also to reproduce original ecosystems as closely as possible in terms of composition, structure, and ecological functions. Even if invaded by native vegetation, tree plantations may fail to provide adequate habitat for some animal species (Medina et al. 2002).

1 Fundacio´n EcoAndina/Wildlife Conservation Society Colombia Program, Apartado Ae´reo 25527, Cali, Colombia. 2 Address correspondence to D. Correa, email [email protected] 3 Present address: Departamento de Ecologı´a y Comportamiento Animal, Instituto de Ecologı´a A. C., Xalapa, 91070 Veracruz, Me´xico. 4 Present address: Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa.

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forest types and the ash plantation but not in the alder plantation, reflecting population recovery after the dry season. Alder leaf litter apparently buffered seasonal variations in arthropod richness and abundance. Composition of morphospecies was different among forest types. Although arthropod richness was lower in ash plantations compared to secondary forest, plantations still provided habitat for these organisms. On the other hand, the alder plantation was not different from secondary forest at the same elevation. At our site, plantations are embedded in a forested landscape. Whether our results apply to different landscape configurations and at different spatial scales needs to be established. The use of plantations as a restoration tool depends on the objectives of the project and on local conditions of forest cover and soils. Key words: Leaf Litter Arthropods, Restoration, Plantations, Andean forests.

In the Colombian Andes, monospecific tree plantations have been used for restoring vegetative cover in watershed protection programs. Although the initial objective was to stabilize soils and regulate water flow, in some cases these plantations have been included in protected areas. The Otu´n River drainage in the Central Cordillera of the Andes is one example (London˜o 1994). Mid- and upper elevation (1,700–2,600 m) forests in this drainage were cleared for pasture establishment during the early twentieth century. Starting in the late 1950s, local government agencies started buying lands and establishing monospecific tree plantations. Stands of native Andean alder (Alnus acuminata) were planted at the upper elevations (2,400–2,600 m) and exotic Chinese ash (Fraxinus chinensis) at the lower elevations (1,800–2,000 m). Other plots, intermixed with plantations, were abandoned at different times to natural regeneration, with seed rain provided by remnant forest patches. These lands were later included in two protected areas. Plantations were not managed and were invaded by native vegetation. Thus, although the canopy is dominated by one species, plantations have well-vegetated understories and edges. The resulting mosaic of tree plantations and forest patches of different ages is ideal for evaluating plantations as restoration tools. Previous studies have indicated that alder plantations are poorer in plant species than adjacent

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second-growth forest of the same age (Murcia 1997). However, the understories of alder and ash plantations do provide adequate habitat and resources for at least some species such as bess beetles (Passalidae), dung beetles (Scarabaeinae), and birds (Murcia et al. 2001; Medina et al. 2002; Dura´n & Kattan 2005). In this article, we present results of an evaluation of the leaf-litter arthropod fauna of alder and ash plantations and adjacent secondary forest of the same age. We compared samples from ash plantation and forest at 1,900 m and alder plantation and forest at 2,430 m, obtained at two different periods (March–April and September) in a year. Thus, our comparisons involved forest type (plantation vs. forest), elevation, and sampling period. Arthropods play a fundamental role in leaf-litter dynamics by reducing decomposing material to small particles and by facilitating nutrient cycling through the activity of microorganisms. Small changes in soil arthropod communities may have major effects on local nutrient dynamics (Heneghan & Bolger 1998). In addition, litter arthropods form complex and diverse food webs (Pfeiffer 1996; Barberena-Arias & Aide 2002, 2003) and provide resources for other predators such as ground birds. Therefore, leaflitter arthropods play an important role in forest dynamics and their recovery is a crucial part of forest restoration (Heneghan & Bolger 1998; Longcore 2003). Study Area and Methods This study was conducted at the Otu´n River catchment located on the western slope of the Central Cordillera of the Colombian Andes, east of the city of Pereira. This catchment was cleared for pasture establishment during the first decades of the twentieth century. Native forest remained only on the steepest slopes and in some scattered patches in the valley. During the late 1950s and 1960s, the regional utilities company (a government agency) started buying lands for a revegetation program to protect the watershed (London˜o 1994). To accelerate development of a canopy cover, monospecific tree plantations were established and interspersed with patches that were abandoned to natural regeneration. Presently, the region is a small-scale mosaic of plantations and forest of different ages and is over 80% forested. The entire catchment is under protection status from 1,700 m of elevation to the Otu´n River headwaters at Otu´n Lake, at 3,800 m. Three reserves provide this protection: Los Nevados National Park (53,000 ha of high-elevation ecosystems above 2,600 m), Ucumarı´ Regional Park (4,240 ha, 1,700–2,600 m), and Otu´n Quimbaya Flora and Fauna Sanctuary (489 ha at the southwest corner of Ucumarı´). The Otu´n River presently supplies water for urban consumption and irrigation to a population of over two million people. The rain regime in the area is bimodal, with precipitation peaks in April and October, a mild dry season in December–January, and a stronger dry season in July–August (Fig. 1).

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The study was conducted in 1995. We selected two sites, one at 1,900 m and the other at 2,430 m. At the upper elevation, we compared alder plantations and adjacent secondary forest of the same age (about 40 years), and at the lower elevation, the comparison involved ash plantation and adjacent secondary forest. In each habitat type, we took 20 leaf-litter samples from points scattered throughout habitat patches covering about 30 ha each. Each sample was 50 3 50 cm2 of leaf litter. Samples were sieved manually with a funnel, and the sieved material was put into a white tray, from which we manually collected all arthropods for a standardized time of 10 minutes. Samples were taken twice, the first during March–April, in the middle of the rainy season, and the second in September, at the beginning of the rains after the midyear dry season (Fig. 1). Thus, the total of samples collected was 160. Arthropods were separated into class, order, and, whenever possible, family (e.g., Coleoptera). Within each group we assigned individuals to morphospecies. For analyses, we used a nested analysis of variance model, with habitat type (forest and plantation) nested in site (elevation) and with sampling period as a covariate. We compared three variables: number of families, number of morphospecies, and number of individuals. Because variables did not conform to normality and homogeneity of variances, we performed analyses using the log-transformed variables. To compare the four forest types in terms of morphospecies composition, we conducted a detrended correspondence analysis (DCA).

Results In the 160 leaf-litter samples, we obtained a total of 4,236 arthropods belonging to 370 morphospecies in 49 families, representing the classes Arachnida, Crustacea, Hexapoda, Chilopoda, and Diplopoda (Appendix 1).

Figure 1. Mean (±SD) monthly precipitation (1961–2002) and 1995 monthly rainfall for El Cedral weather station (lat 4°429N, long 75°329W) located at 2,120 m, halfway between sampling sites (1,900 and 2,430 m) in the Colombian Central Andes. SP1 and SP2 indicate sampling periods. Rainfall in July 1995 was above the average, but August was very dry (22 continuous days without rainfall).

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There were significant differences among forest types in the number of families (F[2,152] ¼ 6.77, p ¼ 0.002), number of morphospecies (F[2,152] ¼ 5.87, p ¼ 0.004), and number of individual arthropods (F[2,152] ¼ 10.96, p < 0.001) (Fig. 2). The number of families was highest in the natural forest at the lower elevation (Fig. 2). There were no differences between the ash plantation at the lower elevation and the two forest types at the higher elevation. There was a significant interaction between elevation and sampling period ( p ¼ 0.049). The number of families increased in the second sampling period at the lower elevation but not at the higher elevation. Likewise, the number of morphospecies was highest in the natural forest at the lower elevation but was not different between the ash plantation and the two upper elevation forest types (Fig. 2). The number of morphospecies increased for the second sampling period at all sites except at the alder plantation.

The number of individual arthropods captured was higher overall at the lower elevation than at the higher elevation and increased for the second sampling period, except at the alder plantation (Fig. 2). However, there was a significant interaction between forest type and sampling period. The number of arthropods was higher in the alder plantation than in the adjacent regenerated forest ( p ¼ 0.0002) and decreased in the alder plantation for the second sampling period ( p ¼ 0.02), that is, the alder plantation behaved in an opposite way relative to the three other forest types. There was a mixed response in the patterns of richness and abundance of the different taxonomic groups of arthropods among forest types and elevations. The number of families, morphospecies, and individuals of Arachnida collected was relatively homogeneous in all samples, except for the natural forest samples at the lower elevation in the second sampling period. In these samples, the

Figure 2. Mean (±SD) number of arthropod families, morphospecies, and individuals per leaf-litter sample, obtained in two forests types (natural regeneration and tree plantation) at two elevations (1,900 and 2,430 m) and in two sampling periods (SP1 and SP2; see text for dates) in the Central Andes of Colombia (n ¼ 20 samples per type of forest, elevation, and sampling period).

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number of individuals of Arachnida increased significantly (F[3,152] ¼ 13.9, p < 0.001). This effect was due to an enormous increase in the number of spiders (Araneae). Spiders also showed a decrease in the number of individuals from the first sampling period (X ± SD ¼ 2.5 ± 1.9 per sample) to the second (X ± SD ¼ 0.4 ± 0.7). Acari also showed differences between sampling periods (F[1,152] ¼ 12.64, p ¼ 0.038) and between elevations (F[1,152] ¼ 12.8, p < 0.001). These organisms were more abundant in the second sampling period (X ± SD ¼ 1.3 ± 1.8) than in the first (X ± SD ¼ 0.4 ± 0.8) and at the upper elevation (X ± SD ¼ 1.2 ± 1.7) than at the lower elevation (X ± SD ¼ 0.5 ± 1.1). Pseudoscorpions were in general scarce. Crustacea (mostly Isopoda) were more abundant in the leaf litter of the alder plantation than at any other site (F[3,152] ¼ 13.94, p < 0.001). Hexapoda, on the other hand, showed varied responses as expected from their great ecological diversity. Individuals of Coleoptera were more abundant (F[1,152] ¼ 26.5, p < 0.001) in the second sampling (X ± SD ¼ 7.8 1 6.5) than in the first (X ± SD ¼ 3.9 ± 2.9). This difference was more marked in regenerated forest at the upper elevation, where a mean of 3.6 (±1.4) individuals per sample was obtained in the first sampling and 11.5 (± 7.9) in the second sampling. The response of Coleoptera was mostly driven by Staphylinidae, which represented over 44% of all individual beetles and almost 10% of all arthropods collected (Appendix 1). For several insect groups, there was a significant effect of elevation on abundance, but this effect was not consistent among taxonomic groups. Cockroaches (Blattaria) were 10 times more abundant (F[1,158] ¼ 72.9, p < 0.001), dermapterans almost 7 times (F[1,158] ¼ 9.4, p ¼ 0.003), and ants 10 times (F[1,158] ¼ 27.5, p < 0.001) at the lower elevation. On the other hand, dipterans (F[1,158] ¼ 4.2, p ¼ 0.04) and collembolans (F[1,158] ¼ 12.3, p < 0.001) were more abundant at the upper elevation. Chilopoda and Diplopoda also showed contrasting patterns. Spirobolids were more abundant at the lower elevation and particularly in the ash plantation (F[3,152] ¼ 37.9, p < 0.001), in contrast to Polydesmids, which were more abundant at the higher elevation (F[1,158] ¼ 15.6, p < 0.001). Chilopods, on the other hand, were more abundant at the upper elevation forests. Geophilomorphs were more abundant in the alder plantation than in all other forest types (F[3,152] ¼ 8.1, p < 0.001) but were scarce, with less than one individual per sample. Scolopendrids were only found in the first sampling period and only at the upper elevation. The DCA showed differences in morphospecies composition among the four forest types (Fig. 3). The first axis explained 56% of the variation and was mostly associated with differences between the two sampling periods at the upper elevation. The second axis, in contrast, represented 37% of the variation and was associated with differences in composition between secondary forest and ash plantation at the lower elevation.

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Figure 3. Detrended correspondence analysis for four forest types at two elevations and two sampling periods, based on abundances of 370 morphospecies. The first axis (eigenvalue ¼ 0.56) is associated with differences between sampling periods at the upper elevation. The second axis (eigenvalue ¼ 0.37) is generated by differences in composition between secondary forest and ash plantations at the lower elevation.

Discussion Overall, our results showed an effect of forest type on the richness, abundance, and composition of leaf-litter arthropods. There were, however, complex interactions between forest type, elevation, and sampling period. Richness and abundance of arthropods were in general highest at the lower elevation secondary forest. A decrease in diversity with elevation is a well-documented phenomenon for many taxonomic groups (Olson 1994; Lomolino 2001; Nor 2001; Medina et al. 2002; Kattan & Franco 2004). At a local scale, this decrease is related to ecosystem productivity and climatic factors, particularly in arthropods. In our study, however, this pattern was not consistent among taxonomic groups. Species richness of cockroaches, dermapterans, and ants decreased with elevation, but dipterans and collembolans showed the opposite trend. We observed great spatial heterogeneity among the four sampled forests, so these patterns could change temporally. Spatial variability in abundance, diversity, and composition (‘‘patchiness’’) is apparently a consistent feature of litter and soil arthropods (Dangerfield 1997; BarberenaArias & Aide 2002). Differences between sampling periods are likely related to seasonal effects in water content of the leaf litter. Population densities of leaf-litter arthropods increase at the beginning of the rainy season (Levings & Windsor 1982, 1984, 1985; Tanaka & Tanaka 1982; Adis 1984; Ananthakrishnan 1996), particularly if the dry season was intense (Levings & Windsor 1982, 1985; Dangerfield 1997), as was the case in this study. In contrast, population densities decrease as the wet season progresses and litter becomes

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saturated (Frith & Frith 1990). In our study, the response of arthropods in the alder plantation was opposite to that in the other forest types in that diversity and abundance were not lower in the rainy season. In addition, species composition changed between the two temporal samples. Leaf-litter production in alder plantations is higher than in mixed cloud forest, and in spite of their higher nitrogen content, alder leaves decompose slower than other leaves under the same conditions (Murcia, unpublished data). Thus, litter accumulates more rapidly in the alder plantation. Litter mass correlates with insect species richness because litter accumulation provides increased resources and structural complexity (Barberena-Arias & Aide 2003). Alternatively, a deeper leaf-litter layer could provide more refuges and maintain moisture during the dry season, buffering population declines during this period. Our capture method was biased toward mobile macroarthropods, so groups such as Acari and Collembola were under-represented in our samples (3.3 and 4.5%, respectively, of all individuals). In contrast, these organisms represent 70–90% of arthropods in other studies (Frith & Frith 1990; Pfeiffer 1996). On the other hand, Diplopoda represented 22% of arthropods captured in our study, much higher than the values reported in other studies (Pfeiffer 1996) in which this group represents less than 2%, even if Acari and Collembola are removed from the analysis. Abundance of millipedes is related to availability of partially decomposed leaves with high calcium content and low content of secondary metabolites (Levings & Windsor 1982; Pfeiffer 1996). Our results indicated that the leaf-litter arthropod fauna was in general richer in the naturally regenerated forest than in the adjacent ash plantation (1,900 m), and composition was different between these two forest types. Litter insect diversity increases with secondary succession (Barberena-Arias & Aide 2003), so ash may be retarding succession, as occurs in alder plantations (Murcia 1997). However, no differences in litter insect richness were observed between forest and alder plantation (2,400 m), which may be related to the buffering effect of alder litter. Other studies conducted at the same site have produced mixed results. Although plant species richness is lower in plantations than in secondary forest of the same age, this does not necessarily translate into functional differences, particularly in the understory; in addition, the response depends on the particular taxonomic group or process studied (Murcia 1997; Garcı´a 2000; Murcia et al 2001; Useche 2001; Lentijo 2002; Medina et al. 2002; Dura´n & Kattan 2005). We must bear in mind that at our site, plantations are presently embedded in a forest matrix. Although soils were profoundly disturbed by cattle ranching for several decades, there were remnant forest patches in the region that presumably served as recolonization sources and litter insect communities may recover rapidly after a perturbation (Barberena-Arias & Aide 2002). In this case, the best chance to recover a fully functional tropical forest, with a species composition and structure

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resembling the original forest, is probably through natural regeneration (Murcia 1997), although preliminary work to restore soils may be necessary. The best course of action in a particular restoration project depends on initial conditions and the endpoint desired. In particular, the presence of a soil seed bank or nearby seed sources will dictate what options are available. Both conditions may be absent when soils have been disturbed for a long time and when deforestation is extensive. The use of plantations has been promoted because they may modify local conditions that favor the establishment of other plants or because they provide perches for birds that deposit seeds (McClanahan & Wolfe 1993; Da Silva et al. 1996; Haggar et al. 1997; Powers et al. 1997; Wunderle 1997). In addition, plantations may serve other purposes, such as providing resources for human communities (Ewel & Putz 2004). Thus, although natural regeneration may be the ideal choice for restoring a native ecosystem, plantations remain a valuable tool to assist the process and may be the only option in some cases.

Acknowledgments We are thankful to the Corporacio´n Auto´noma Regional de Risaralda and the former INDERENA (presently the National Parks Unit), in particular Eduardo London˜o and Jorge Marulanda, for logistical and financial assistance ´ for providing meteorofor this study and to CENICAFE logical data. Additional funding was provided by the John D. and Catherine T. MacArthur Foundation. We thank Carolina Murcia for statistical advice and for sharing unpublished data.

LITERATURE CITED Adis, J. 1984. Seasonal igapo´ forests of central Amazonian black-water rivers and their terrestrial arthropod faunas. Pages 245–268 in H. Sioli, editor. The Amazon. Limnology and landscape ecology of a mighty tropical river and its basin. Dr W. Junk Publishers, Dordrecht, the Netherlands. Ananthakrishnan, T. N. 1996. Forest litter insect communities: biology and chemical ecology. Oxford & IBH Publishing, Co. Pvt. Ltd., New Delhi, India. Barberena-Arias, M. F., and T. M. Aide. 2002. Variation in species and trophic composition of insect communities in Puerto Rico. Biotropica 34:357–367. Barberena-Arias, M. F., and T. M. Aide. 2003. Species diversity and trophic composition of litter insects during plant secondary succession. Caribbean Journal of Science 39:161–169. Dangerfield, J. M. 1997. Abundance and diversity of soil macrofauna in northern Botswana. Journal of Tropical Ecology 13:527–538. Da Silva, J. M. C., C. Uhl, and G. Murray. 1996. Plant succession, landscape management, and the ecology of frugivorous birds in abandoned Amazonian pastures. Conservation Biology 10:491–503. Dura´n, S. M., and G. H. Kattan. 2005. A test of the utility of exotic tree plantations for understory birds and food resources in the Colombian Andes. Biotropica 37:129–135. Ewel, J. J., and F. E. Putz. 2004. A place for alien species in ecosystem restoration. Frontiers in Ecology and the Environment 2:354–360.

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Frith, D., and C. Frith. 1990. Seasonality of litter invertebrate populations in an Australian upland tropical rain forest. Biotropica 22: 181–190. Garcı´a, C. 2000. Efecto de tres estrategias de restauracio´n de bosques sobre el proceso de herbivorı´a en Palicourea (Rubiaceae). Undergraduate Thesis. Universidad de Los Andes, Bogota´, Colombia. Haggar, J., K. Wightman, and R. Fisher. 1997. The potential of plantations to foster woody regeneration within a deforested landscape in lowland Costa Rica. Forest Ecology and Management 99: 55–64. Heneghan, L., and T. Bolger. 1998. Soil microarthropod contribution to forest ecosystem processes: the importance of observational scale. Plant and Soil 205:113–124. Kattan, G. H., and P. Franco. 2004. Bird diversity along elevational gradients in the Andes of Colombia: area and mass effects. Global Ecology and Biogeography 13:451–458. Lentijo, G. M. 2002. Estratificacio´n vertical de la avifauna en un bosque de regeneracio´n natural, un bosque maduro y una plantacio´n monoespecı´fica. Undergraduate Thesis. Universidad del Valle, Cali, Colombia. Levings, S. C., and D. M. Windsor. 1982. Seasonal and annual variation in litter arthropod populations. Pages 355–387 in E. G. Leigh, A. S. Rand, and D. M. Windsor, editors. The ecology of a tropical rain forest. Seasonal changes and long-term rhythms. Smithsonian Institution Press, Washington, D.C. Levings, S. C., and D. M. Windsor. 1984. Litter moisture content as a determinant of litter arthropod distribution and abundance during the dry season on Barro Colorado Island, Panama. Biotropica 16:125–131. Levings, S. C., and D. M. Windsor. 1985. Fluctuations in litter arthropod populations. Journal of Animal Ecology 54:61–69. Lomolino, M. V. 2001. Elevation gradients of species density: historical and prospective views. Global Ecology and Biogeography 10: 3–13. London˜o, E. 1994. Parque regional natural Ucumarı´, un vistazo histo´rico. Pages 13–21 in J. O. Rangel, editor. Ucumarı´: un caso tı´pico de la diversidad bio´tica andina. Corporacio´n Auto´noma Regional de Risaralda, Pereira, Colombia. Longcore, T. 2003. Terrestrial arthropods as indicators of ecological restoration success in coastal sage scrub (California, U.S.A.). Restoration Ecology 11:397–409.

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Lugo, A. E. 1997. The apparent paradox of reestablishing species richness on degraded lands with tree monocultures. Forest Ecology and Management 99:9–19. McClanahan, T. R., and R. W. Wolfe. 1993. Accelerating forest succession in a fragmented landscape: the role of birds and perches. Conservation Biology 7:279–288. Medina, C. A., F. Escobar, and G. H. Kattan. 2002. Diversity and habitat use of dung beetles in a restored Andean landscape. Biotropica 34:181–187. Murcia, C. 1997. Evaluation of Andean alder as a catalyst for the recovery of tropical cloud forests in Colombia. Forest Ecology and Management 99:163–170. Murcia, C., G. Kattan, and A. Galindo. 2001. Recovery of bess beetles key to long-term restoration of Andean forests (Colombia). Ecological Restoration 19:254–255. Nor, S. M. 2001. Elevational diversity patterns of small mammals on Mount Kinabalu, Sabah, Malaysia. Global Ecology and Biogeography 10:41–62. Olson, D. M. 1994. The distribution of leaf litter invertebrates along a neotropical altitudinal gradient. Journal of Tropical Ecology 10: 129–150. Parrotta, J. A., J. W. Turnbull, and N. Jones. 1997. Catalyzing native forest regeneration on degraded tropical lands. Forest Ecology and Management 99:1–7. Pfeiffer, W. J. 1996. Litter invertebrates. Pages 137–182 in D. P. Reagan and R. B. Waide, editors. The food web of a tropical rain forest. University of Chicago Press, Chicago, Illinois. Powers, J. S., J. P. Haggar, and R. F. Fisher. 1997. The effect of overstory composition on understory woody regeneration and species richness in 7-year-old plantations in Costa Rica. Forest Ecology and Management 99:43–54. Tanaka, L. K., and S. K. Tanaka. 1982. Rainfall and seasonal changes in arthropod abundance on a tropical oceanic island. Biotropica 14:114–123. Useche, A. 2001. Efecto de dos estrategias de restauracio´n sobre la remocio´n de frutos en Palicourea deviae en el Parque Natural Regional Ucumarı´, Risaralda. Undergraduate Thesis. Universidad del Valle, Cali, Colombia. Wunderle, J. M. 1997. The role of animal seed dispersal in accelerating native forest regeneration on degraded tropical lands. Forest Ecology and Management 99:223–235.

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Arachnida Acari Araneae Opiliones Pseudoscorpionida Crustacea Amphipoda Decapoda Isopoda Chilopoda Geophilomorpha Scolopendromorpha Unidentified Diplopoda Polydesmidae Spirobolidae Unidentified Hexapoda Blattaria Coleoptera Cantharidae Carabidae Chrysomelidae Curculionidae Elateridae Histeridae Pselaphidae Ptilodatilidae Scydmaenidae Staphylinidae Tenebrionidae Unidentified Collembola Entomobryidae Unidentified Dermaptera Unidentified Diplura Campodeidae Japygidae

Class/Order/Family

8 24 1 — 23 24 2 22 — 72 51 18 3 141 2 — 1 — 2 1 1 16 4 6 11 5 25 1 25 2 — 11

1 6 — 7 3 1 2 3 2 26 1 31 1 2 6 1 1

53 19 26

SP1

55 11 36 4 4 4 1 — 3 6 3 2 1 39 10 5 24 161 4

No. of Morphospecies

Forest

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6

5 12

— 8 — 2 2 — 1 2 — 101 — 114

48 25 16 1 6 9 — — 9 14 13 — 1 53 21 6 26 395 3

SP2

9 18

106 —

1 4 — 1 2 3 4 1 17 16 2 28

80 12 51 2 15 133 — — 133 41 34 3 4 103 54 8 41 259 9

SP1

3 7

1

3 —

— 4 — 6 — — — 6 3 52 — 93

55 42 8 4 1 63 — — 63 39 32 — 7 115 59 10 46 245 6

SP2

Plantation

No. of Individuals

2,300 m

1 1

12

1 1

— 8 1 5 — 1 2 2 2 29 1 30

47 5 35 5 2 4 — 1 3 5 3 — 2 31 6 3 22 171 8

No. of Morphospecies

6 3

9

5 —

— 5 — 1 — 2 13 6 4 22 — 22

56 3 46 2 5 36 — 1 35 13 11 — 2 65 21 25 19 192 32

SP1

Forest

12 11

32

8 1

— 8 1 — — — 50 — 3 36 — 36

151 20 117 4 10 57 — 1 56 16 12 — 4 124 24 48 52 337 61

SP2

— 3

4

17 —

— 1 — 2 — — 2 1 4 42 4 34

35 7 1 — 6 165 17 116 32 267 55

2 35 —

21

23

SP1

6 —

18

16 —

— 5 — 2 — — 3 7 — 49 — 35

65 19 36 5 5 85 — — 85 21 20 — 1 247 20 165 62 308 44

SP2

Plantation

No. of Individuals

1,900 m

Appendix 1. Number of morphospecies and individual arthropods obtained in 20 leaf-litter samples at each forest type, elevation, and sampling period.

37 54

72

161 38

1 36 1 16 5 6 89 27 37 329 11 387

531 140 321 18 52 442 1 2 439 175 125 25 25 944 267 396 281 2,144 212

Total

0.87 1.27

1.70

3.80 0.90

0.02 0.85 0.02 0.38 0.12 0.14 2.10 0.64 0.87 7.77 0.26 9.14

12.54 3.31 7.58 0.42 1.23 10.43 0.02 0.05 10.36 4.13 2.95 0.59 0.59 22.29 6.30 9.35 6.63 50.61 5.00

%

No. of Individuals

Leaf-Litter Arthropods in Restored Forests

101

102

6 — — 2 2 3 1 2 3 — — 7 1 — — — 1 383 35

1 1 1 26 3 1 1 5 3 1 — 10 1 3 — 5 1 280 44

— 546 34

— 3

2 — 1

2 1 —

2 13

7 —

5 3 98

—

Arthropods were separated into class, order, and, for most of the hexapods, family.

Unidentified Diptera Muscidae Simulidae Unidentified Orthopotera Gryllidae Unidentified Heteroptera Pentatomidae Unidentified Homoptera Cercopidae Cicadellidae Unidentified Hymenoptera Formicidae Microhymenoptera Unidentified Lepidoptera Geometridae Unidentified Thysanoptera Unidentified No. of individuals No. of families

Appendix 1. Continued

— 678 35

— —

3 — 2

1 — —

2 3

7 8

— 2 10

—

— 586 31

— 3

6 — —

1 — —

1 7

1 2

3 3 34

—

— 267 41

1 3

14 — 10

1 2 3

2 7

3 2

1 1 16

—

— 408 33

1 1

48 — 1

— — 2

— 1

1 2

— — 5

—

— 757 34

—

26 — 10

1 1 2

7 7

7 4

1 — 12

—

— 630 25

— 1

69 — —

— — —

17 6

— —

— — 5

—

— 911 29

— 3

77 — 5

— 2 3

5 13

— —

— 2 13

—

1 4,236 49

1 11

238 1 19

8 4 7

35 52

25 19

9 10 179

6

0.02

0.02 0.26

5.62 0.02 0.45

0.19 0.09 0.17

0.83 1.23

0.59 0.45

0.21 0.24 4.23

0.14

Leaf-Litter Arthropods in Restored Forests

Restoration Ecology

MARCH 2006