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Crecimiento y desarrollo inicial de arbóreas nativas en un arreglo silvopastoril en La Guajira, Colombia | Growth and initial development of native trees in a silvopastoral arrangement in La Guajira, Colombia النص الكامل
2022
Lombo Ortiz, Darwin Fabian | Arias Rojas, Jaime Andrés | Rivera Rojas, Milton | Caballero López, Adelina Rosa | Rúa Bustamante, Clara Viviana | Hernandez Martinez, Cristian Camilo
Crecimiento y desarrollo inicial de arbóreas nativas en un arreglo silvopastoril en La Guajira, Colombia | Growth and initial development of native trees in a silvopastoral arrangement in La Guajira, Colombia النص الكامل
2022
Lombo Ortiz, Darwin Fabian | Arias Rojas, Jaime Andrés | Rivera Rojas, Milton | Caballero López, Adelina Rosa | Rúa Bustamante, Clara Viviana | Hernandez Martinez, Cristian Camilo
Se evaluó el crecimiento y desarrollo de cuatro especies arbóreas nativas en su etapa inicial de desarrollo establecidas en un arreglo silvopastoril para ramoneo de ovinos y caprinos en territorio de una comunidad indígena Wayuu ubicada en la zona de amortiguamiento del Parque Nacional Natural de Macuira en la GuajiraColombia. Se establecieron 3594 plántulas de cuatros especies diferentes en un diseño de bloques completos al azar con cuatro repeticiones, para la evaluación de crecimiento se tomaron diez unidades experimentales por bloque. Se estimaron parámetros de crecimiento e índices de mortalidad y supervivencia. Se estimó un nivel de supervivencia para Guazuma ulmifolia y Pithecellobium dulce de 39% y 48 % respectivamente. Mientras, Caesalpinia coriaria yCordia alba registraron los mayores valores con 86 y 75%. C. alba mostro los índices de desarrollo más importantes respecto al conjunto de las especies con una altura de 39.75 + 11.90 cm y diámetro a la base del tallo de 9.81 + 3.68 mm. En cuanto al crecimiento periódico mensual en altura existe decrecimiento en altura para P dulce, esto responde a la muerte de la parte apical de algunos individuos debido a herviboría en el sitio de estudio. Igualmente se aprecia una tasa de mortalidad mensual considerablemente alta para las especies G. ulmifolia y P. dulce de 20.48 y 12.28 % respecto al conjunto de las especies, situación que reduce su vida media en 5.5 y 7.5 meses de persistir las condiciones actuales de manejo. Finalmente, las especies C. coriaria y C. alba presentan una mejor adaptación en su etapa inicial de desarrollo a las condiciones bióticas y abióticas de la zona en estudio y manejo actual del sistema silvopastoril.
اظهر المزيد [+] اقل [-]Evaluación del estado y revisión de técnicas de conservación de suelos pertenecientes a ecosistemas de bosque seco tropical. النص الكامل
2022
Hernandez Bustos, Laura Camila | Acevedo Pabón, Paola Andrea | Cabeza Rojas, Iván Orlando | Universidad Santo Tomás
La degradación de los suelos en ecosistemas de bosque seco tropical (BST) hace que las dinámicas ambientales en los municipios de nuestro territorio como lo es El Espinal, Tolima tomen un enfoque más genérico a la hora de hablar sobre los usos, la conservación y la importancia que tienen a nivel local y nacional. Conocer el estado actual de los suelos en relación con el ecosistema de bosque seco tropical en el Espinal Tolima hizo que se lograra una investigación más efectiva a la hora de comparar y analizar la implementación de técnicas de recuperación como el biochar y el compostaje, describiendo cada una de estas enmiendas en función de la recuperación que se requiere en las muestras caracterizadas por el crecimiento de biomasa. Cada muestra se estudió en el laboratorio midiendo los parámetros físico-químicos como capacidad de retención de agua, nitrógeno total y materia orgánica. La finalidad de este estudio fue establecer una línea base mediante la comparación de suelos muestreados en una explotación agrícola de El Espinal (Tolima), con el objeto de identificar si los componentes del suelo necesitan ser restaurados con las técnicas mencionadas. Parte del estudio encontró que las principales características han sido la intervención agrícola, ganadera y asentamientos urbanos, generando cambios en su composición fisicoquímica, disminución de materia orgánica, entre otros. Al finalizar, se concluye que los parámetros no muestran mayor degradación (WHC >50%, MO < 1-5%, NTK >0,25%), sin embargo, por las condiciones del ecosistema, del clima, de las actividades agrícolas y demás, es necesario hacer seguimientos, ya que, la disminución de la fertilización inorgánica y su complementación mediante la incorporación de enmiendas orgánicas y biochar puede generar un efecto positivo en la búsqueda del equilibrio productivo entre los elementos que componen el suelo. | The degradation of soils in tropical dry forest ecosystems (BST) makes the environmental dynamics in the municipalities of our territory, such as El Espinal, Tolima, take a more generic approach when talking about the uses, conservation and importance they have at the local and national level. Knowing the current state of the soils in relation to the tropical dry forest ecosystem in Espinal Tolima led to more effective research in comparing and analyzing the implementation of recovery techniques such as biochar and composting, describing each of these amendments in terms of the recovery required in samples characterized by biomass growth. Each sample was studied in the laboratory by measuring physico-chemical parameters such as water retention capacity, total nitrogen and organic matter. The purpose of this study is to make a comparison of soils, which is done by means of a statistical analysis in order to recognize if the components of the soil need to be restored with the aforementioned techniques, as well as to highlight the importance of these techniques since they have been used as an invaluable resource within the framework of the Colombian soils. Part of the study found that the main characteristics have been agricultural intervention, livestock and urban settlements, generating changes in its physicochemical composition, decrease of organic matter, among others. At the end, it is concluded that the parameters do not show greater degradation (WHC >50%, MO < 1-5%, NTK >0. 25%), however, due to the conditions of the ecosystem, climate, agricultural activities and others, it is necessary to follow up, since the reduction of inorganic fertilization and its complementation through the incorporation of organic amendments and biochar can generate a positive effect in the search for a productive balance between the elements that make up the soil. | Ingeniero Ambiental | http://unidadinvestigacion.usta.edu.co | Pregrado
اظهر المزيد [+] اقل [-]Effect of sun-dried and fresh cassava leaves on growth of Tilapia (Oreochromis niloticus) fish fed basal diets of rice bran or rice bran mixed with cassava root meal النص الكامل
2010
Chhay, T. | Borin, K. | Sopharith, N | Preston, Thomas R. | Aye, Tin Maung
The growth response of Tilapia fish (Oreochromis niloticus) to supplementation with fresh or dried leaves of a sweet variety of cassava was studied in 1 m deep ponds (each 4 m * 2.5 m * 1 m). Rice bran or rice bran mixed with cassava root meal was provided as the energy source (20-24% of feed DM), the mixed feed being given at the rate of 5% of fish LW. There were 30 fish per pond with average initial weight of 6 g per head. The treatments were arranged as a 2*2 factorial in a Completely Randomized Design (CRD) with 4 replicates. The first factor was cassava leaf processing (sun-dried or fresh); the second factor was energy source (rice bran or rice bran mixed with cassava root meal). The cassava leaves and roots were from a local “sweet” variety traditionally planted by farmers for human consumption. The experiment was conducted for 100 days. Daily gain in weight and length, and the ratio weight: length after 100 days of growth, did not differ among treatments. All the fish survived and there was no evidence of HCN toxicity. Water quality parameters were not affected by the treatments. There were no interactions between sources of protein and of energy. It is concluded that the feeding of cassava leaves with rice bran can be readily adopted by small scale farmers as both these feed resources are readily available in rural areas.
اظهر المزيد [+] اقل [-]Estimation and comparison of benefits due to feeding hay and silage during the dry season on commercial dual-purpose cattle production systems in Honduras and Costa Rica النص الكامل
2006
Schoonhoven, Aart van | Holmann, Federico J. | Argel M., Pedro J. | Pérez, E. | Ordoñez, J.C. | Chaves, J.
Smallholders with dual-purpose cattle production systems in most Central America experience a shortage of forages during the dry season (4-8 month. As a result, substantially lower milk production and weight gain occurs. Dual-purpose operations seeking to maximize milk and beef production in the dry season can produce and feed hay or silage to their livestock. The increase in milk and beef production due to feeding hay or silage during the dry season on commercial dual-purpose cattle productions systems, the production costs of making silage or hay and the benefits as a result of feeding silage or hay are estimated and compared in Honduras and Costa Rica. Due to feeding silage or hay, farmers in Honduras and Costa Rica have increased milk production during the dry season. The costs of feeding hay are lower in both countries, although farmers feed a higher amount (kg DM/cow/day) than silage. Feeding silage or hay to milking cows is profitable in both countries. The income-cost ratio and the net benefit ($/cow/day) due to feeding these feedstuffs are positive. Farmers with milking cows in Honduras realise a higher income-cost ratio and net benefit due to feeding silage and hay than farmers in Costa Rica. Likewise, beef cows or young livestock supplemented with these feeding alternatives don't loose weight during the dry season. In Honduras as well in Costa Rica, it is profitable to feed silage or hay to beef cows or young livestock. Currently, no silage and a small hay market exist in Honduras. Possibly, these will develop due to an increasing demand for these profitable feedstuffs. In Costa Rica thanks to the efforts of agricultural organisations, a hay market of different qualities is developing.
اظهر المزيد [+] اقل [-]The use of cassava products in animal feeding
2012
Buitrago A., Julián A. | Gil, Jorge L. | Ospina Patiño, Bernardo