Colombia Forestal

8

Authors: Nelson Gutiérrez Guzmán, Eduardo Valencia Granada, Renso Alfredo Aragón Calderón

In order to evaluate the current operating conditions of wastewater treatment systems of small scale coffee growers in the south of Huila a lab-scale prototype (S 1:25) was constructed. It was composed of both a sediment tank and a filter fit in series, simulating similar operating conditions used by coffee producers. Removal of biological oxygen demand (BOD5) and suspended solids (SS) was performed in wastewater from coffee bean processing. A 23 factorial experimental design for the evaluation of the type of sedimentation tank, type of filter and hydraulic retention time (HRT) in the sedimentation tank was employed. The results showed high removal efficiencies of suspended solid concentrations (more than 95%), and low removal efficiencies in BOD5 (about 20%). The combination of tank type 1 (square with a lower area), filter type 1 (upflow anaerobic filter – UAF) and HRT of 30 hours had the highest removal efficiency.

11

Authors: Diana Lucia Giraldo Charria, Victor Manuel Nieto Rodríguez, Mónica Sarmiento, Nuno Borralho

The study presents the results of a comparison between Pilodyn and other direct estimates such as disks and cores, to determine wood density of Eucalyptus pellita F. Muell clones.The accuracy of Pilodynas a reliable selection criteria for determining the density in standing trees was evaluated. The analysis was based on a collection of ten clones developed by Reforestadora de la Costa, in the Orinoquia of Colombia as part of their breeding program. Wood density of cores and disks were calculated based on the standard water displacement method. The results confirm E. pellita is a high density species, with an average value of 580 kg/m3, based on disks. The estimates of clonal heritability for the three methods were high and similar (between 0.47 and 0.55), as were the phenotypic and genetic correlations between them (between 0.43 and 0.96). This indicates that Pilodyn is an effective indirect selection tool for assessing wood density of E. pellita clones, especially when many individuals need to be assessed per clone. However, Pilodyn is not recommended as a tool for selecting individuals.

13

Authors: Dolors Armenteras, Nelly Rodríguez Eraso

Over the past few years there have been a considerable number of studies on deforestation in Latin America. Deforestation rates reported up to the 2000s are generally lower in the region than in other tropical areas. The causes of deforestation in Latin America are similar to those identified in other regions. In general, studies of deforestation are regional or very localized and do not permit comparison of intraregional variability within the American tropics. In this paper we present results obtained from a meta-analysis of 283 articles on deforestation rates for different types of forests in Latin America (Atlantic, Montane , Dry, Lowland and others). Causes of deforestation identified in the literature and published at the national or subnational level since 1990 are also analyzed. There is an overall deforestation rate of -1.54 for the region, but results indicate a high variability of deforestation rates between countries and that there are even cases of forest cover gains, e.g. in El Salvador. The highest deforestation rates are in dry forest followed by montane forests. Most countries identify agricultural and livestock expansion as the main cause of deforestation.

18

Authors: Wilmar Loaiza Cerón, Yesid Carvajal Escobar & Álvaro Javier Ávila Díaz

The Sustainability Index of Agricultural Production Systems (SIAPS) was used to assess the ecological integrity of study area in the Centella watershed (Dagua, Valle del Cauca). Four components were evaluated: soil management and hedging, water management, solid waste, and social, economic, political and institutional aspects for a total of 23 indicators. SIAPS was used to compare production systems and to estimate conditions of integrity amongst farms. The results permitted definition of minimum thresholds of ecosystem capacity for supporting anthropogenic use. 38% of the farms were constituted as best performers, 56% are "above the threshold" and only 6% were "below the threshold". The key issue is not that farmers use the exact same techniques used by those of the "headlight", but that they are presented as an example of the management and conservation of resources, planning and promotion of sustainable human development on farms.

7

Authors: Juan Carlos Camargo García, Juan David Suarez Franco

The preservation of guadua (Guadua angustifolia) culms is an important process which affects their quality after harvesting and their subsequent utilization as a raw material in handicraft, furniture and construction. Boron and boric acid are frequently used in the preserving solution (PS). To ease the adsorption the culm diaphragm is usually drilled before immersion in the PS. We performed a factorial experiment to determine the possible effects of drilling the culm diaphragm on compression and shear strength. Two measures of culm maturity were considered. The traditional measure is defined by the external features of the culms and another is based on the time since culm emergence. Variance analyses did not show any significant (p > 0.05) difference in mechanical properties when the diaphragm was drilled. Nevertheless, those culms with maturity defined using the traditional approach had significantly lower values of compression and shear strength. In addition, culms with higher moisture content were significantly stronger.

14

Authors: César Augusto Polanco Tapia, Jenny Paola Caicedo Velásquez, Diego Hernán Beltrán Hernández

The wood anatomy of Caryodaphnopsis cogolloi Van der Werff was studied using xilological characteristics identified in transverse and longitudinal wood cuts (tangential and radial views). Wood natural durability was established in an accelerated laboratory trial, using two methods: a soil block method established by the Colombian Technical Standard NTC 1127 (NTC for its acronym in Spanish), and an Agar block method ruled by the standard norm EN 350-1: 1994 in which the decay fungi used were Trametes versicolor and Gloeophyllum trabeum. The durability was assessed by weight loss and analysis of the fungal decay characteristics over a four month incubation period on the wood samples where each month the colonization mechanism, development and fungal growth characteristics were observed, along with the effects on the cell wall. Caryodaphnopsis cogolloi wood is significantly resistant to fungal white and brown rotting showing a mean weight loss of 5.1% and 6.1% respectively in the soil block method, while in the agar block method the weight loss was 5.9 % for both fungi. Decay patterns in the samples demonstrated that T. versicolor eroded cell walls and produced enlargement in the cell wall holes in some cells, while G. trabeum produced a reduction in cell wall thickness in a few cells.

16

Authors: Andrés Avella Muñoz, J. Orlando Rangel Churio

Characterizations of oak forests according to their floristic composition and structure and the identification of the main use requirements of local communities were performed. This permitted recommendations for the sustainable use and preservation of these forest types in the Guantiva-La Rusia-Iguaque conservation corridor (Santander-Boyacá, Colombia). The oak forests correspond to the Quercus humboldtii - Billia rosea major forest formation, which can be categorized into a hierarchical structure of seven forest types. The Q. humboldtii - Ocotea calophylla forests present in the high Andean fringe (>2200-3200 m.a.s.l); the Q. humboldtii - Alchornea grandiflora forests, common in the Andean region include two types of forests, Q. humboldtii - Blakea cuatrecasii, and Q. humboldtii - Cyathea multiflora forests; furthermore, these types of forests comprise the Q. humboldtii - Daphnopsis caracasana and Q. humboldtii - Pouteria baehniana forests. The final forest type is the Virola macrocarpa - Q. humboldtii forests present in the sub-Andean life zone. According to interviews with members of local communities oak forests are considered the main components of ecosystems of high cultural and social value. The interviews identified two principle uses of oaks, for fuel and for land tenure and property maintenance (fence posts, stakes for crops, timber and tool handles). According to ecological characterization and conservation status assessments the Virola macrocarpa - Q. humboldtii, Q. humboldtii - Pouteria baehniana and Q. humboldtii - Daphnopsis caracasana forests can be used by the community with technical prescriptions. The Q. humboldtii - Blakea cuatrecasii and Q. humboldtii - Ocotea calophylla forests should not be used under any circumstance and should be subject to strict strategies for their protection and ecological restoration. The future of oak forests is uncertain unless appropriate strategies based on the generation of co-management agreements with local communities for sustainable use and conservation are proposed and implemented.

19

Authors: Cristopher Edgar Camargo Roa, Jesús Enrique Andrades Grassi, Raúl Oswaldo Vidal García

Digital elevation models -DEM- as a visual representation of landforms and altitude have been very useful in the study of topography. This research took place in a 3.39 km2 area of the La Machirí torrential micro-watershed (Táchira State, Venezuela). Its purpose was to evaluate a DEM generated through a process of digital photogrammetry that was also checked against a DEM edited from existing level curves in topographic charts. Exploratory Spatial Data Analysis (ESDA) and the Multiple-Point Geostatistics (Minimal Distance Analysis, Special Pattern Analysis, Variogram, and Variographic Analysis of Surfaces) methods were used. Differences between the two models were identified generated by the sum of the errors caused by the spatial distribution of checkpoints marked for the photogrammetric process (less than the number of checkpoints of a normal distribution, possible spatial bias between checkpoints and indications of spatial dependence phenomena), the error generated from the interpolation method applied during the process, and by the error caused by local erosion processes. The first assessment indicated a difference in the surface area of 0.57 ha and of 9.41 hm3 in volume in both DEMs. A zoned analysis indicated that at least three more checkpoints are necessary in order to get a more accurate DEM.

11

Authors: Eduard Muñoz

A catalogue of species and an identification key for the native fern and lycophyte genera of Las Delicias Botanical Garden is presented. The garden is located in Andean forest between 2700-2800 a.s.l., in the Inzá township, Cauca, Colombia, in an undisturbed wooded area. An essential objective of Las Delicias Botanical Garden is the conservation of the local flora in order to protect the habitat of the many animal species in this habitat. This study is one of the first in the Botanical Garden in an initiative proposed by the Guambiana community. Collections in the interior and periphery of the Botanical Garden were made. In total there were 70 species in 27 genera and 16 families in an area of 75 ha. Notes on some morphological features of the plants and their habits are also presented.

13

Authors: Diego Fernando Vélez-Sánchez, Víctor Manuel Nieto-Rodríguez

This study evaluated the performance of eleven rubber clones (Hevea brasiliensis) in a large-scale clonal field 12 and 36 months after planting. Clonal materials were established using a randomized complete block design with four replications of 100 trees per clone. Growth in height and circumference were evaluated. The clones that showed the greatest circumference growth at 12 and 36 months were FX 3864 (6,69 cm and 10,99 cm) and IAN 710 (6,48 cm and 11,41 cm), those with lesser growth in circumference at 12 months were IAN 873 with 4.65 cm and PR255 with 4,61 cm, while the clone with least growth at 36 months was IAN 873 with 7,80 cm. IAN 710 (4,97 m and 5,20 m) had the best growth in height at 12 and 36 months, while PR 255 with 2,21 m and PR 303 with 2,12 cm had the lowest height growth at 12 months and at 36 months IAN 873 had least growth with 2,82 m.

18

Authors: Edgard E. Cantillo Higuera, Melisa Gracia Cuéllar

Remnants of vegetation in the eastern hills of Bogotá (Parque Nacional Enrique Olaya Herrera, Quebrada La Vieja and Agroparque Los Soches) were floristically characterized by preferentially sampling twenty surveys of 0.07 ha distributed at altitudes between 2730 m and 3170 m. According to the Caldas-Lang classification the study area has a semi-wet cold climate, and according to the Holdridge system it corresponds to lower montane moist forest. We classified seven phytosociological units, dominated by Chusqueo scandentis - Weinmanietalia tomentosae vegetation, four units correspond to recovering forests of a Macleanio rupestris -Weinmanion tomentosae vegetation alliance, and another that corresponds to the Piperi bogotensis -Miconietum squamulosae type. The greatest diversity was found in the National Park with 48 families, 78 genera and 101 species, followed by Quebrada La Vieja with 44 families, 69 genera and 87 species, and finally Agroparque Los Soches with 40 families 63 genera and 78 species. We highlight the presence of ecologically important species such as Dicksonia sellowiana and Dysopsis paucidentata. Shannon -Weaver index values range between 3.14 and 3.99 and the average for the six vegetation types was 3.61. Vegetation units had very similar values, but the Ocotea sericea-Weinmania tomentosa and Oreopanax floribundum-Axinaea macrophylla communities had the lowest.

22

Authors: Alexandra Duque, Esteban Álvarez, Wilson Rodríguez, Álvaro Lema

We analyse the relationship between landscapescale variables (fragment area, shape, connectivity, altitude, edge contrast, forest type, etc.) and vascular plant richness in an Andean forest of northern Colombia. Using a vegetation map at a scale of 1:10000, we randomly selected 39 fragments (from a total of 700) in each of which we established a 200 m2 plot where we counted the total number of species of vascular plants. The sample consisted of fragments of between one ha and 840 ha at altitudes of between 1800 and 2800 m. In the 60 plots (1,2 ha in total) we found 108 families, 259 genera and 556 species of vascular plants. Species richness varied between 34 and 74 per 200 m2 plot. The analysis showed that the individual variables most closely related to species richness (according to the Pearson r coefficient) are the total area of the fragment (r = 0,43, p <0,001, n = 60), the central area of the fragment (r = 0,49, p <0,001, n = 60) and the fragment edge contrast (r = - 0,48, p <0,00, n = 60). Finally, we built multiple regression models to explain up to 32,6 % of the variation in species richness of each fragment. We discuss the usefulness of these models for the identification of small scale conservation priorities.

11

Authors: Jhon Alvarado, Hernán Jair Andrade, Milena Segura

The increase in greenhouse gas emissions from anthropogenic sources has resulted in climate change, which affects all living beings. Coffee (Coffea arabica L.) plantations, in monoculture or together with timber species such as salmwood (Cordia alliodora), mitigate climate change due to fixation of atmospheric CO2 that is deposited in biomass and soils. This study was carried out in the municipality of Líbano, Tolima, Colombia with the objective of defining which of the following coffee production systems store more soil organic carbon (SOC): 1) monoculture, 2) agroforestry systems (AFS) with salmwood, and 3) AFS with plantain. Farms with those systems that are the most dominant in the study zone were selected. From each system, five repetitions were identified to be analyzed with a completely randomized design. In each plot or repetition, five samples for bulk density (BD) using the cylinder method and a composite sample for concentration of SOC were taken and analyzed using the Walkley and Black approach. The systems of production did not significantly (p > 0.05) affect either the BD or the concentration of SOC. However, AFS with plantain tended to have less BD than monoculture and AFS with salmwood (0.83 ± 0.03 vs 0.88 ± 0.03 vs 0.92 ± 0.04 g·cm-3, respectively). These systems of production stored between 50 and 54 t·ha-1 of SOC in the top 30 cm, which indicates their capacity for climate change mitigation.

13

Authors: Fermín José Chamorro-García, Daniela León-Bonilla & Guiomar Nates-Parra

The Andean forests of the Eastern Andean high-lands of Colombia have a high conservation priority given the vulnerable condition of species such as Quercus humboldtii (Fagaceae) that inhabit these ecosystems. Beekeeping is regarded as an alternative activity that could play a role in the conservation of Andean forests, but little is known about how the floras of these ecosystems contribute to honey and bee pollen production. We analyzed the contribution of Andean forests to bee pollen production, given the productive potential and commercial importance of this product. Pollen analyses were performed on 25 samples from apiaries near Andean forests located in the states of Cundinamarca, Boyacá and Santander. We found that Q. humboldtii is an important source of pollen with high potential for monofloral bee pollen production. In addition, bees collect pollen from other Andean forests species such as Weinmannia tomentosa, Viburnum spp. and Morella spp. Utilization of bee pollen could lead to incentives to carry out forest conservation practices through beekeeping management.

16

Authors: Victoria Eugenia Vallejo-Quintero

Environmental sustainability is achieved by main-taining and improving soil quality. This quality is defined as “the ability of soil to function” and is evaluated through measuring a minimum set of data corresponding to different soil properties (physical, chemical and biological). However, assessment of these properties does not meet all the conditions necessary to be ideal indicators such as: clearly discriminating between the systems use and / or management evaluation, sensitivity to stress conditions associated with anthropogenic actions, easy measurement, accessibility to many users and short response time. Because loss in quality is associated with the alteration of many processes performed by soil microorganisms they meet the above conditions and have been proposed as valid indicators for diagnosing the impact of changes in land-use and ecosystem restoration. Thus, through the evaluation of the density, activity and /or structure-composition of microorganisms we can determine whether current management systems maintain, improve or degrade the soil. In this article we review the main concepts related to soil quality and its indicators. We discuss the effect of the implementation of silvopastoral systems on soil quality, with an emphasis on the use of microbial indicators.