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Human Impacts on the Cloud Forests of the Upper Guayllabamba River Basin, Ecuador, and Suggested Management Responses
Abstract
The fate of tropandean landscapes in Ecuador is of special concern because of the ongoing biological impoverishment and habitat fragmentation. Ecuador hosts a great variety of ecosystems, ranging from the lush Amazonian forests to snow-capped mountains and from the Andean vergent to the semi-arid Galapagos islands. The topographic complexity of the Andes mountains produces a large number of bioclimatic zones, each with different land use regimes. Ecuador is one of the most biologically diverse nations per unit area (Steinitz-Kannan, Colinvaux, and Kannan 1983) in the neotropics. In addition to the great biodiversity, Ecuador has a rich variety of indigenous cultures, which have lived there for millennia. Post-Colombian anthropogenic pressures have had severe impacts on the land and biotic resource base, with feedbacks on the traditional lifestyles of indigenous peoples. Currently, Ecuador stands at an important environmental crossroad. Therefore, protection of the fragile and fragmented natural tropandean ecosystems is an immediate concern for Ecuadorian land use planning.
... Despite the high value for the biodiversity conservation of this watershed, a number of anthropogenic processes have been associated with the degradation and loss of Inter-Andean Dry Forest and Tropical Montane Forest, such as intensive agriculture, extraction of firewood, and overexploitation of native species (Aguirre et al., 2006(Aguirre et al., , 2011Mittermeier et al., 2011;NatureServe & EcoDecision, 2015). The foregoing impacts on the native forest have been the focus of discussion among environmental entities of government and communities, which have highlighted the need to implement effective conservation strategies for native forest ecosystems (Sarmiento, 1995;Aguirre et al., 2011;Ministerio del Ambiente del Ecuador, 2013;NatureServe & EcoDecision, 2015). ...
... Although there are few specific studies on the diversity of flora and fauna and their state of conservation in the Inter-Andean Dry Forest and Tropical Montane Forest in the HRGW (Sarmiento, 1995;Aguirre et al., 2006Aguirre et al., , 2011Cadena-Ortíz et al., 2015;Cisneros-Heredia et al., 2017), there are no spatio-temporal studies on the transformation state of this landscape, and in particular on the changes in spatial patterns of the native forest ecosystems due to the intensification of agricultural and urban land-use. This type of information is necessary to implement actions or strategies of conservation and restoration at the landscape scale, which offers a way out to the degradation of the ecosystems while ensuring the participation of different levels of governance and the community in this process (Ministerio del Ambiente del Ecuador, 2013). ...
Currently, there is no precise information on the degree of transformation of Tropical Andes hotspot landscape and native ecosystems due to the intensification of agricultural and urban land-use. Proper knowledge of these changes would provide crucial information for planning conservation strategies. We evaluated the impact of the intensification of agricultural and urban land-use on the Inter-Andean Dry Forest and Tropical Montane Forest, both of which are categorized as Critically Endangered, and the state of the landscape in the High Rio Guayllabamba watershed, Ecuador, during the periods 1991–2005 and 2005–2017. The evaluation was carried out using Landsat satellite images of 30 x 30 m pixels and landscape metrics. We found an advanced state of landscape transformation. Since the 1990s, the loss of both ecosystems was largely caused by the conversion of forest to agriculture, resulting in substantial changes in the spatial configuration of these ecosystems. From 1991 to 2017, 19.8 % and 16.1 % of Inter-Andean Dry Forest and Tropical Montane Forest respectively, were converted to agriculture. The loss of Inter-Andean Dry Forest was 28 % and the number of forest patches increased by more than 150%. The loss of Tropical Montane Forest was 16.5 % and the number of forest patches increased by more than 300 %. The largest loss and fragmentation of forest cover occurred from 1991 to 2005. We suggested planning landscape-scale conservation, using the patch-corridor-matrix model. This model is appropriate given the current configuration of the landscape studied, with Inter-Andean Dry Forest and Tropical Montane Forest restricted to small patches sparsely distributed across the landscape.
... Land-use changes in areas of cloud forest affect ecosystem functions irreversibly (Ledo et al. 2009;Hamilton et al. 1994). Activities such as the conversion of forested land to agricultural land, fuel-extraction (Sarmiento 1993) or illegal logging (Aubad et al. 2008), has caused the disappearance and fragmentation of TMCF (Young and León 1993). ...
... Although Philipines (Penafiel 1994), Meso-america (Nadkarni et al. 1995), Ecuador (Sarmiento 1993) and Malasia (Kitayama 1994). In the studied forest, Lauraceae is not the dominant family, other families such as Sabiaceae being more abundant. ...
Cloud forests are unusual and fragile habitats, being one of the least studied and least understood ecosystems. The tropical Andean dominion is considered one of the most significant places in the world as regards biological diversity, with a very high level of endemism. The biodiversity was analysed in an isolated remnant area of a tropical montane cloud forest known as the “Bosque de Neblina de Cuyas”, in the North of the Peruvian Andean range. Composition, structure and dead wood were measured or estimated. The values obtained were compared with other cloud forests. The study revealed a high level of forest biodiversity, although the level of biodiversity differs from one area to another: in the inner areas, where human pressure is almost inexistent, the biodiversity values increase. The high species richness and the low dominance among species bear testimony to this montane cloud forest as a real enclave of biodiversity.
... On the other side, H. ferruginea presented low dominance (small trees, 1.6% of the total basal area), but high abundance and frequency. Their high seed productivity, plasticity, and ecophysiological adaptation may have facilitated their distribution in disturbed areas, however we notice that this species may be also found in mature Andean montane forests [42][43][44]. ...
Composition, diversity, and structure of trees in tropical montane forests are responsive to ecological gradients and local succession. Those parameters are a result of ecological interactions between vegetation, environment, and location. This study identified floristic groups on mainly secondary forests and evaluated how the composition, diversity, and structure of trees correlate with climate, soil, and age since abandonment. We included in our models a measurement of spatial correlation, to explore the role of dispersion. For this purpose, we measured diameter and height of all trees with DBH ≥ 10 cm, in twenty-eight 500 m2 plots, in an elevation range between 2900 and 3500 m. We found 14 indicator species in three floristic groups. Group composition was explained by age since abandonment, which showed strong succession effects. Mean monthly precipitation and Manganese, but not spatial correlation, explained plant composition in these montane forests, suggesting a minor role of dispersion. Species richness and structure of the arboreal vegetation were influenced by interactions between age, precipitation, and soil nutrients concentration. We concluded that in fragmented landscapes, within the rugged region of southern Ecuador, it is possible to find different floristic groups that encompass high variation in their composition.
... However, modern anthropogenic pressures (e.g. land-use change, landcover modification, pollution) arguably exceeded climate as the dominant control on vegetation structure through much of the TMCF of the eastern Andean flank (Sarmiento, 1995). ...
Understanding the impact of landscape-scale disturbance events during the last glacial period is vital in accurately reconstructing the ecosystem dynamics of montane environments. Here, a sedimentary succession from the tropical montane cloud forest of the eastern Andean flank of Ecuador provides evidence of the role of non-climate drivers of vegetation change (volcanic events, fire regime and herbivory) during the late-Pleistocene. Multiproxy analysis (pollen, non-pollen palynomorphs, charcoal, geochemistry and carbon content) of the sediments, radiocarbon dated to ca. 45-42. ka, provide a snap shot of the depositional environment, vegetation community and non-climate drivers of ecosystem dynamics. The geomorphology of the Vinillos study area, along with the organic-carbon content, and aquatic remains suggest deposition took place near a valley floor in a swamp or shallow water environment. The pollen assemblage initially composed primarily of herbaceous types (Poaceae-Asteraceae-Solanaceae) is replaced by assemblages characterised by Andean forest taxa, (first Melastomataceae-Weinmannia-Ilex, and later, Alnus-Hedyosmum-Myrica). The pollen assemblages have no modern analogues in the tropical montane cloud forest of Ecuador. High micro-charcoal and rare macro-charcoal abundances co-occur with volcanic tephra deposits suggesting transportation from extra-local regions and that volcanic eruptions were an important source of ignition in the wider glacial landscape. The presence of the coprophilous fungi Sporormiella reveals the occurrence of herbivores in the glacial montane forest landscape. Pollen analysis indicates a stable regional vegetation community, with changes in vegetation population co-varying with large volcanic tephra deposits suggesting that the structure of glacial vegetation at Vinillos was driven by volcanic activity.
... The Chocó-Andean region of Ecuador is located within 2 of the world's biodiversity hotspots: forests of the Chocó and Andes Tropicales (Sarmiento 1995, Myers et al. 2000, Rieckmann et al. 2011). The region is marked by high levels of biodiversity and endemism, but >50% of the region has been deforested as a result of colonization and unsustainable land use (Gentry 1986, Balslev 1988, Palacios and Neill 1993, Webster and Rhode 2001, Justicia 2007. ...
The Andean bear (Tremarctos ornatus) is the only extant species of bear in South America and is considered threatened across its range and endangered in Ecuador. Habitat loss and fragmentation is considered a critical threat to the species, and there is a lack of knowledge regarding its distribution and abundance. The species is thought to occur at low densities, making field studies designed to estimate abundance or density challenging. We conducted a pilot camera-trap study to estimate Andean bear density in a recently identified population of Andean bears northwest of Quito, Ecuador, during 2012. We compared 12 candidate spatial capture-recapture models including covariates on encounter probability and density and estimated a density of 7.45 bears/100 km² within the region. In addition, we estimated that approximately 40 bears used a recently named Andean bear corridor established by the Secretary of Environment, and we produced a density map for this area. Use of a rub-post with vanilla scent attractant allowed us to capture numerous photographs for each event, improving our ability to identify individual bears by unique facial markings. This study provides the first empirically derived density estimate for Andean bears in Ecuador and should provide direction for future landscape-scale studies interested in conservation initiatives requiring spatially explicit estimates of density. © 2017 International Association for Bear Research and Management.
... Frequent disturbances and subsequent diminishing of the forest cover, especially in ecologically sensitive areas may have led many plant species to be extinct from the earth. Conversion of forests to agricultural land, fuel wood extraction (Sarmiento, 1995), illegal logging (Aubad et al., 2008) and human population densities and trends (Young and León, 1995) have been cited as major threats to TMCFs, leading to their fragmentation or disappearance. Thus, in Sri Lanka, 3,000 ha of montane forests are left in the island at present (Wijesundara, 2012). ...
Plant species in Tropical Montane Cloud Forests (TMCFs) of Dothalugala Man and Biosphere (MAB) Reserve were recorded in twenty six 10 x 15 m 2 experimental plots, aiming to reveal the total species richness and the richness of endemic and threatened flowering plant species in the forest canopy and the understory and, to find out the impacts of cardamom cultivation on the plant diversity of the study area. One hundred and forty eight plant species (77 tree, 46 shrub, 24 climber and one herbaceous species) belonging to 106 plant genera and 55 plant families have been found from the area examined. A high percentage endemicity of plant species (50%) was revealed in this site due to the presence of 74 (38 tree, 29 shrub, 6 climber and one hebaceous) species endemic to Sri Lanka. Similarly, 68 out of all plant species (45.9%) and 47 out of all endemic plant species (63.5%) in these forests were either globally or nationally threatened. The endemic and 'Critically Endangered' Stemonoporus affinis (Dipterocarpaceae) was also found to be thrive in the area. Cardamom cultivation had caused a tremendous reduction in the floristic diversity (total number of species and the number of endemic and threatened species) and the conservation value of TMCFs in Dothalugala MAB reserve. Therefore, the cardamom cultivation and other related disturbances within and adjacent to Dothalugala MAB Reserve should be arrested for the conservation of plant diversity in this fragile ecosystem and, this will eventually contribute towards the conservation of biodiversity not only in Sri Lanka but also in the globe as a whole.
Community-based tropical forest restoration projects, often promoted as a win-win solution for local communities and the environment, have increased dramatically in number in the past decade. Many such projects are underway in Andean cloud forests, which, given their extremely high biodiversity and history of extensive clearing, are understudied. This study investigates the efficacy of community-based tree-planting projects to accelerate cloud forest recovery, as compared to unassisted natural regeneration. This study takes place in northwest Andean Ecuador, where the majority of the original, highly diverse cloud forests have been cleared, in five communities that initiated tree-planting projects to restore forests in 2003. In 2011, we identified tree species along transects in planted forests (n = 5), naturally regenerating forests (n = 5), and primary forests (n = 5). We also surveyed 120 households about their restoration methods, tree preferences, and forest uses. We found that tree diversity was higher in planted than in unplanted secondary forest, but both were less diverse than primary forests. Ordination analysis showed that all three forests had distinct species compositions, although planted forests shared more species with primary forests than did unplanted forests. Planted forests also contained more animal-dispersed species in both the planted canopy and in the unplanted, regenerating understory than unplanted forests, and contained the highest proportion of species with use value for local people. While restoring forest increased biodiversity and accelerated forest recovery, restored forests may also represent novel ecosystems that are distinct from the region's previous ecosystems and, given their usefulness to people, are likely to be more common in the future.
Rapid 21st-century climate change may lead to large population decreases and extinction in tropical montane cloud forest species in the Andes. While prior research has focused on species migrations per se, ecotones may respond to different environmental factors than species. Even if species can migrate in response to climate change, if ecotones do not they can function as hard barriers to species migrations, making ecotone migrations central to understanding species persistence under scenarios of climate change. We examined a 42-year span of aerial photographs and high resolution satellite imagery to calculate migration rates of timberline-the grassland-forest ecotone-inside and outside of protected areas in the high Peruvian Andes. We found that timberline in protected areas was more likely to migrate upward in elevation than in areas with frequent cattle grazing and fire. However, rates in both protected (0.24 m yr(-1)) and unprotected (0.05 m yr(-1)) areas are only 0.5-2.3% of the rates needed to stay in equilibrium with projected climate by 2100. These ecotone migration rates are 12.5 to 110 times slower than the observed species migration rates within the same forest, suggesting a barrier to migration for mid- and high-elevation species. We anticipate that the ecotone will be a hard barrier to migration under future climate change, leading to drastic population and biodiversity losses in the region unless intensive management steps are taken.
Conservation biology has traditionally focused on the fine scale and the species level of biological organization (Soulé and Wilcox 1980), and biotic conservation is only one of the various goals that has directed the preservation and management of natural areas and resources. Resource management goals have largely been utilitarian or commercial, such as the maintenance of large areas for watersheds; preservation of marshes, bogs, and seasonal wetlands for flood water storage, nursery areas, and flow continuity in river systems, and the sustained yield of forests, fisheries, and wildlife (Temple et al. 1988; Aplet, Laven, and Fiedler in press). There have, however, been both practically and theoretically motivated calls for widening the focus to include scales beyond that of the individual site and levels of organization above that of the species (Soulé 1989; Western 1989) to approach new goals. This essay will explore the relationship of this new frontier for conservation biology to advances in ecology. Much of the new ecological focus of conservation biology is driven by the shift in the overarching paradigm of ecology itself. We begin by defining the concept of paradigm and characterizing the classical paradigm of ecology. The classical paradigm had definite implications for conservation, and these are shown to be problematical. Therefore, we outline the contemporary paradigm in ecology and show how the science of ecology has been affected by the shift in paradigm.
• • • John Harper • • • Nature conservation has changed from an idealistic philosophy to a serious technology. Ecology, the science that underpins the technol ogy of conservation, is still too immature to provide all the wisdom that it must. It is arguable that the desire to conserve nature will in itself force the discipline of ecology to identify fundamental prob lems in its scientific goals and methods. In return, ecologists may be able to offer some insights that make conservation more practicable (Harper 1987). The idea that nature (species or communities) is worth preserv ing rests on several fundamental arguments, particularly the argu ment of nostalgia and the argument of human benefit and need. Nostalgia, of course, is a powerful emotion. With some notable ex ceptions, there is usually a feeling of dismay at a change in the sta tus quo, whether it be the loss of a place in the country for walking or rambling, the loss of a painting or architectural monument, or that one will never again have the chance to see a particular species of bird or plant.
Ecología y Fitoecologia. Casa de la Cultura Ecuatoriana
- M Acosta-Solis
El Mapa Ecológico y Bioclimático del Ecuador. Ministerio de Agricultura y Ganaderia, Program de Regionalización Agraria
- L Canadas
Antologia Ecológica del Ecuador. Desde la selva hasta el mar. Casa de la Cultura Ecuatoriana
- F O Sarmiento
Priorities for conservation of the biodiversity in the Colombian Andes
- H P Van Venzen
- HP Venzen Van