РАСПРОСТРАНЕНИЕ РОДА ЦЕДРЕЛА В ЭКВАДОРЕ

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INTRODUCTION Each year between 2010 and 2015, worldwide 7,6 million hectares (ha) of forest were lost due to the deforestation. South America is not an exception, is one of the continents with the highest rate of deforestation (2 million ha/year) [6]. Same as Ecuador with one of the highest rates of the Continent according to the Food and Agriculture Organization of the United Nations (annual rate of 1.8% for the 2001-2010 period) and the main causes are related to urban sprawl, expansion of agricultural and pasturelands, lack of adequate government policies, high demand for timber products, logging and forest fires [15; 16; 26]. Although, the annual rate of deforestation in Ecuador has been reduced in recent years, it continues affecting a large range of species, such as Cedrela. Cedar is demanded by the timber and construction industries due to the high quality of its wood in terms of color, fragrance, strength and durability [3; 8; 17). In Ecuador, the genus Cedrela P. Browne (Meliaceae) includes 4 species: Cedrela odorata, C. fissilis, C montana and C. nebulosa [21]. These species have shown a huge decrease in their population size and distribution due to their high quality timber. According to CITES data between 2002 to 2009, Ecuador exported 342 m3 of cedar wood, however in the international market, this wood replaced collapsed sales of other species such as mahogany, this lasted a couple of years before collapsing the exports. Furthermore, the selective logging of big and better formed trees is a common practice in Ecuador, which erodes the genetic quality of the remain populations [21; 25]. Other threats to the future survival of this genus are the expansion of human settlements, conversion of land for agricultural and livestock use, the construction of highways and the extraction of oil and minerals [26]. All of these threats trigger the genetic diversity diminish and generate problems in the conservation and management policies of these plants. As a consequence of the selective logging of cedar, C. fissilis is an endangered species and Cedrela odorata is considered as a vulnerable species [10]. Despite the economic and ecological relevance of the genus Cedrela, studies on the current status and the distribution of its species in Ecuador are scarce [11; 21; 22]. This study provides information about the distribution of Cedrela genus in Ecuador, which can be a valuable contribution to the management of these species. METHODS Georeference data was obtained of herbarium specimen.s from the National Herbarium of Ecuador (QCNE), Herbarium of the Pontificia Universidad Católica del Ecuador (QCA), Ministry of the Environment (MAE) and Walter Palacios, the expert in Meliaceae. In addition, data was included from field collections of the Phylogeography of Cedrela [14]. Two hundred forty seven specimens (247) were collected and georeferenced (Garmin Etrex Summit and Magellan Meridian Platinum GPS). The map of geographical distribution of the genus Cedrela in Ecuador was generated using data collected and vegetable formations division of the continental Ecuador [2; 12; 20; 23]. ArcGIS 10.3 Software was used in this study. RESULTS AND DISCUSION On large scale, there was a clear division in the geographical distribution of Cedar species in Ecuador: Cedrela montana is distributed in the Andean Region between 805 and 3200 meters above sea level; C. nebulosa in the Andean Region in heights between 1420 to 2300 masl; Cedrela odorata was the most widespread species located in three regions: Pacific (330-825 masl), Amazonian (200-1300 mas) and Insular region at 350 m. Cedrela fissilis was found only in the Amazon Region at elevations between 200 and 510 masl (Fig. 1 and 2). 3500 Altitude (masl) 3000 2500 2000 1500 1000 500 0 Altitudinal range according to species and region 0 10 20 30 40 50 60 Specimen Numbers C. montana (Andes Region) C. odorata (Pacific Region) C. odorata (Amazon Region) C. odorata (Insular Region) C. fissilis (Amazon Region) C. nebulosa (Andes Region) Fig. 1. Scatter plot of Cedar species distribution by altitudinal range and region The Cedar distribution in the Ecoregions of Ecuador classified by [23; 20] showed a notorious preference of each species to different formations. As shown in Figure 2, the most widely distributed species was Cedrela odorata, found in the following Ecoregions: Lowland Evergreen Forest of the Amazon, and Flooded Lowland Forest of the Amazon at heights from 200 to 1300 masl. In the Pacific Region it was presented in Lowland Evergreen Forest, Piedmont Evergreen Forest of the Coast Mountains and Deciduous Forest of Lowlands, at heights from 330 to 825 masl. In Galápagos Islands C. odorata was found in the Xeric Scrub Ecoregion at 350 masl. Cedrela montana was restricted to the Andean Region in the following Ecoregions: Lower Montane Evergreen Forest and Montane Mist Forest of the Western Andes, Lower Montane Evergreen Forest of the North and Central Andes, and High Montane Evergreen Forest of the Eastern Andes in heights between 805 and 3200 masl. In the previous Ecoregion and in the Montane Mist Forest of the Eastern Andes, the species C. nebulosa was also located in heights between 1420 to 2300 masl. Cedrela fissilis appeared only in the Amazon Region in the Lowland Evergreen Forest and Flooded Forest of the Amazon at heights between 200 to 510 masl (Fig. 2). The regions where Cedrela species were located are enclosed in three different biodiversity hotspots. C. odorata in the Coast Region (Mache Chindul Ecological Reserve and Maglares Churute Nature Reserve) is located in Chocó-Darién-Western Ecuador Hotspot [4]. Both, Cedrela odorata and C. fissilis in the Amazon and Cedrela montana is in the Hotspot of the Tropical Andes (Table 1). The C. odorata distribution determine that is adapted to two habitat types: tropical rainforest and tropical monsoon where the climate is warm dry and warm humid in the regions of the Central and Insular Coast and in the North Coast and Amazon Regions, respectively. Adaptations due to growth in different regions have been recorded in previous studies [18; 19], where it was established that C. odorata populations of Xeric (high solar radiation and low humidity) and Mesics environments (higher humidity and lower radiation) of Costa Rica differ in morphological and adaptive characteristics such as seed weight, seedling size, root neck diameter (RND) of the seedling, leaf size, weight of the sheet. In Xeric environment C. odorata populations showed higher values in the morphological characteristics than C. odorata of Mesics habitat as an adaptation to survive in drought. Fig. 2. Map of Cedrela Distribution in Ecuador based in the plant formations classification of Sierra et al (1999) and Olson (2002). Symbology: C. odorata, blue circle; C. montana, red circle; C. fissilis, yellow circle and C. nebulosa, green circle (ArcGis 10.3) The leaves of C. odorata sampled in dry and humid environments showed differences in size. In addition, in the research developed by [14] about molecular phylogenetics of Cedar in Ecuador using chloroplasidic genes cpDNA and transcripted internal spacers (ITS) was suggested a possible incipient speciation and/or a subspecies status over C. odorata populations. The two lineages found for this species were correlated with the region of distribution, one from the Central Coast Region and Insular Region (dry climate) and the other from the North Coast and Amazon Region (humid climate). However, to corroborate this hypothesis it is suggested to perform morphological and ecological studies to determine the parameters on which the dry and humid environments caused a selective pressure and therefore its adaptation. Summary of cedrela species location according to hotspot and plant formations Table 1 Species Hotspot (h) or Region (r) Plant formation (Sierra et al., 1999; Olson, 2002) Cedrela odorata Amazonía (r) Lowland Evergreen Forest of the Amazon Piedmont Evergreen Forest Flooded Lowland Forest of the Amazon Choco-Darien (h) Lowland Evergreen Forest Deciduous Lowlands Forest Island (r) Xeric Scrub Cedrela montana Tropical Andes (h) Lower Montane Evergreen Forest of the Western Andes Montane Mist Forest of the Western Andes Lower Montane Evergreen Forest of the North and Central Andes High Montane Evergreen Forest of the Eastern Andes Cedrela nebulosa Andes (h) High Montane Evergreen Forest of the Eastern Andes Montane Mist Forest of the Western Andes Cedrela fissilis Amazon (r) Lowland Evergreen Forest of the Amazon Flooded Lowland Forest of the Amazon Cedrela montana and C. nebulosa share the same Andean region, however the first one is more widely distributed. This ecoregions are characterized by the frequent presence of moving fog. The climate is pluvial humid to hyperhumid and the soil is well moist and drained. The altitudinal range between both species also varies slightly, being that C. montana can reach a higher altitude of up to 3200 masl. Finally, C. fissilis was the least dispersed and in a lower altitudinal range, it was located only in the Amazon region. CONCLUSION With the exception of the studies of [21], there is only scarce information on current distribution of cedar in Ecuador; with this study is cleared the distribution of cedar taking to consider the altitude and the ecoregions where each species develops. Also we found that C. odorata of tropical rainforest and tropical monsoon climates shows morphological differences like the size leaf. To prove if there are adaptations to both habitats morphological, ecological and phylogenetic studies must be carried out. The distribution of cedar has been observed to be restricted to tree main regions depending of each species. All of these regions coincide with highly deforested areas, hence, Cedrela genus must be consider a priority conservation group due to their vulnerability to extinction as a result of anthropogenic activities that destroy or modify the environment; In general, deforestation in Ecuador has shown a high rate and is one of the main cause to the climate change with important implications for ecosystem functioning and biodiversity conservation [24]. The deforestation plays an important role in increasing global warming because has enhanced emission of greenhouse gases such as carbon dioxide, methane, and nitrous oxide, especially it has contributed 6-17% of global anthropogenic CO2 emissions to the atmosphere [1; 5; 9]. Therefore, deforestation avoidance is helpful for supporting reduced greenhouses gases and also provides other benefits such as conservation of ecosystem biological diversity, prevention of forest fragmentation, protection of watersheds, improvement of local livelihoods, and provision of additional income for developing countries [13; 16]. The threat of species is the direct consequence of Cedrela logging, in particular C. fissilis which is as a rare species (restricted distribution and sparse populations) and in danger of extinction. Therefore, the cedar reforestation can improve the current state of Cedrela in Ecuador; in order to have a good reforestation management, the actual distribution and the habitat preferences of each species must be considered. In addition, because cedar distribution concurs with biological ‘hotspot’, it has a high conservation value [24] owing hotspots have been considered such prior areas to research about of the origin of the biologic diversity [7].

Об авторах

Сильвия Алехандра Йерена

Российский университет дружбы народов

Email: alellerenag@gmail.com
магистр экологии и природопользования кафедры экологии Российского университета дружбы народов Российская Федерация, 115093, Москва, Подольское шоссе, 8/5

Наталья Салинас

Университет Флориды

Email: alellerenag@gmail.com
кандидат технических наук кафедры садоводства Университета Флориды. США США, 32611, Флорида

Орландо Луиз Оливеира

Федеральный университет Викоза

Email: alellerenag@gmail.com
кандидат наук (генетика и селекция растений) кафедры биохимии и молекулярной биологии Федерального университета Викоза. Бразилия Бразилия, 36570-900, Викоса, ул. Питер Генри Рольфс

Моника Хадан-Герреро

Университет вооруженных сил - ESPE

Email: alellerenag@gmail.com
кандидат наук PhD (c) кафедры естественных наук и сельского хозяйства Университета вооруженных сил - ESPE. Санголки, Эквадор. Эквадор, 171103, Санголки, просп. Главн. Руминьяви

Клаудия Сеговиа-Салцедо

Университет вооруженных сил - ESPE

Email: alellerenag@gmail.com
кандидат наук PhD в области молекулярной систематики кафедры естественных наук и сельского хозяйства Университета вооруженных сил - ESPE. Санголки, Эквадор Эквадор, 171103, Санголки, просп. Главн. Руминьяви

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