VOL. 11, NO. 23, DECEMBER 2016 ISSN 1819-6608 ARPN Journal of Engineering and Applied Sciences ©2006-2016 Asian Research Publishing Network (ARPN). All rights reserved. www.arpnjournals.com ENVIRONMENTAL SUSTAINABILITY STRATEGIES FOR COUNTERACTING EROSION EFFECTS AND SOIL DEGRADATION IN THE TATACOA DESSERT Jennifer Katiusca Castro, Nestor Enrique Cerquera and Freddy Humberto Escobar Universidad Surcolombiana, Avenida Pastrana, Neiva, Huila, Colombia E-Mail: [email protected] ABSTRACT Three procedures aimed at establishing environmental sustainability strategies to counter the effects of erosion and soil degradation which contribute to improve productivity and biodiversity in the ecoregion of the Desert Tatacoa located in Neiva, Huila State, Colombia (South America). Phytogeographicalindex affinity of the Tatacoa Desert with other areas of tropical dry forest (bs-T) of Colombia were determined; the results allowed establishing the most suitable species living in this area for regreening work, promoting the conservation of native species of tropical dry forest in the Tatacoa Desert and knowing an existing phytogeographic affinity between other parts of the country to improve plant cover of all affected areas. Likewise, a model to estimate the gross value of agricultural production was built and found that the advance of the desertification process of this ecoregion has a significant reducing effect on soils’ production. Finally, a comparative analysis of respiratory activity and the mineralization rate of soil organic matter from different localities of the tropical dry forest (bs-T)of Huila state, which showed a different behavior for each treatment reflected as significant respiration changes and a mineralization rate whichprove that the potential degradation of soil microorganisms, for middle- and low organic matter content is low. This document attempts to benefit the community that lives in the study area and the academic community that provides advisory and assistance to the population of the mentioned area. Keywords: phytogeographic affinity, tropical dry forest, economic valuation, respirometry, mineralization rate. INTRODUCTION grass and bushes which leads to create erosion process and Desertification and soil damage threaten to finish to impede the vegetable cover development. Furthermore, the strategic ecosystems and endangered economic certain amount of water rain falls as intensive heavy rain, activities of the eco-region people which leads to reduce then, water precipitation and surface rain-off are very their life quality. erosive. These two factors plus the anthropic effect have According to Ortiz (2013), desertification is the generated the formation of furrows and the activation of degradation of arid soils, semi-arid and dry sub-humid collapse and caving in the terrains with low vegetation. zones caused mainly by climatic variations and such Besides, it is important to perform researches highly human activities as crop and excessive grazing, contributing to direct efforts towards improving economic deforestation and scarcity of water. According to UN and social by adequate soil and water use according to the through the program for the environment (PNUMA) desert potential. (1994), desertification threatens one fourth of the planet’s This study has a result a model for the economic life, affects directly more than 250 million people and value of the desertification effects and soil degradation in endangers the living resources of people from more than the Tatacoa desert. 100 countries since soil productivity for agriculture and cattle rising is reduced. 1. INTRODUCTION In Huila State (Colombia) this type of The Tatacoa is a region belonging Villavieja inconvenient is presented in arid and semi-arid zones (Huila state) municipality. It is located at the north of belonging to the Tatacoa desert eco-region in the Huila state, in the Magdalena River Valley. It presents dry mayorship of Villavieja. It is located in the north part of and erosive conditions where the native plants are adapted the Huila state and according to Espinal (1990), is has two by morphologic and physiologic characteristics. zones with bio-temperature in °C and rain precipitation en According the bioclimatic system proposed by mm corresponding to: very dry tropical woodland (bms- Holdridge (1967), the Tatacoa belongs to tropical dry T) with +- 24°C, rain 500-1000 mm; dry tropical forest and very dry tropical forest (Espinal, 1990; Olaya, woodland (bs-T) +- 24°C, rain 1000-2000 mm. 1995). These types of forest is found in Colombia Olaya, Sanchez and Acebedo (2001) affirm that especially in the inter andean valleys of Magdalena, Patía in the Tatacoa desert predominate surface soils, eroded and Chicamocha Rivers (Llanos, 2001). with rock outcrops and many natural drainage channels Forero (2005) affirms that only 3% or less of and dry-sterile edaphic association with shorter original natural forest exists in such zones asTatacoa.This availability of water periods and longer humidity deficit is because the cover plant was remived in the region for periods. Soils of these zones present sedimentary implementing extensive cattle activities which, in few accumulation materials very sensitive to erosion. Cattle, years, caused degradation problems and lost of soil natural sheep and goats belonging to the zone are fed with native capability to infiltrate and conserve humidity. Currently, 13477 VOL. 11, NO. 23, DECEMBER 2016 ISSN 1819-6608 ARPN Journal of Engineering and Applied Sciences ©2006-2016 Asian Research Publishing Network (ARPN). All rights reserved. www.arpnjournals.com the Tatacoa presents extensive erosion processes, increase 2. METHODOLOGICAL PROCEDURE of salt levels, desertification and scarcity of live in the soil. The deteriorating factors of soil resources reduce the 2.1. Phytogeographical affinity biologic diversity and, therefore, prevent to reach the A literature review of the number of existing sustainable development goals, (Cortés, 2002). documented vegetable species in the Tatacoa zone and Several researches on strategic ecosystems have other national zones were carried out to elaborate a been carried out in Colombia. To name some of them: consolidated document so the Jacard similarity indexes Vargas (2001) studied the geological aspects of the can be determined using a commercial statistics software Tatacoa Desert and Malagón (2003), studied the soils’ by conforming n x P size matrix (102x9) where the typologies by región in Colombia; Calvachi (2012); vegetable species of the Tatacoa Desert represented the Mendoza (1999); Rangel & Franco (1985) and Llanos hundred and two rows (n) and the area where the life Bs-T (2001), have performed inventories of vegetable species of zone in Colombia is presented corresponds to the nine the Tatacoa Desert and phytoecological observations in columns (P). The Jacard similarity index is binary which several life regions in the Colombian Central mountain indicate that forming the similarity matrix a number one chain. (1) is written if the specie is present in a given ecoregión Ortiz &Polanía (2013), described the advance of and zero (0) if it is absent. Subsequently, the the desertification process in this ecoregion, Delgado, phytogeographical affinity index (PAI) and estimated by Hernández &Castaño (2012) made a computational study Equation (1) following the methodology proposed by on the radiation of the desert atmosphere. By the same Herrmann & Tappan (2013): token, Guerrero, Sarmiento & Navarrete (2000) analyzed the cretacic replacement of the Magdalena River Valley; nn (1) Setoguchiet al.(1985) found primate fossilsfrom the PAI (* PAii AC )/() AC i medium Miocen; Villaroel, Brieva& Cadena (2012) found ii00 fossils of mammals belonging to the late Pleistocene and Sánchez (2001) found some fossil remains of invertebrate, being n the species number in the place, PA is the fish, reptiles and birds. similarity index and y AC abundance category (Rare: 1, Olaya& Sánchez (2001) have documented the scarce: 2, common: 3, very common: 4, native: 5). The interaction of Tatacoa Desert with important hydric results permitted to establish not only the more common resources of the High Magdalena River. As far as the species in the studied zone but also what species can be fauna is concerned, Losada& Molina (2011) built and cultivated in other biogeographical zones of the country. inventory of bird species existing in the life zone of dry tropical forest; Acosta-Galvis (2012) found amphibious in 2.2. Economical assessment of the erosion process the dry enclaves of Tatacoa and its influence area in the advance High Magdalena. Sánchez &Olaya (2001) The basic aggregated model was utilized. This allowed mentionedzoological groups predominating in the higher observing the desertification effect on the “capital and extension environment and the ecologic role of them in the work” variables expressed in the model as “bulk value of Tatacoa region. agriculture production” (VBP). For the economical Although the Tatacoa Desert has been researched assessment of the advance in the erosion process was by several science disciplines, it was necessary to establish employed the basic aggregated model according to the the index of phytogeographical affinity that allows methodology used by Morales (2012), which permits to measuring the inclusion of foreign species into the diverse observe the desertification effects on “capital and work” similarity resulting as a consequence of the environmental variables,