Cálculo de la huella hídrica en fincas ganaderas ubicadas en la cuenca del río La Villa, Panamá

Abstract

El presente estudio se realizó en fincas ganaderas ubicadas en la cuenca del río La Villa, durante la época seca (enero – abril) y parte de la época lluviosa (mayo – julio). La cuenca presenta una precipitación promedio anual entre 1000 a 2400 mm; ocurriendo la mayoría de estas (91%) entre diciembre a abril. La temperatura máxima en la parte alta de la cuenca es de 29,6°C y mínima de 19°C; en la cuenca media, se registran temperaturas máximas de 31,9°C y mínima de 20°C; en la cuenca baja, la temperatura máxima es 34,2°C y mínima 20,7°C. El presente documento está conformado por tres secciones, un sección de aspectos generales del estudio y dos artículos. En el primer artículo se desarrolló una tipología de fincas ganaderas según el nivel tecnológico que presentaban. La clasificación se realizó en dos fases: i) inicialmente se analizó una base de datos ya existente, cuya muestra fue de 211 fincas la cual se obtuvo a partir de una población de 3116 productores ganaderos. Mediante revisión de literatura y criterios del equipo técnico IDIAP se definieron 5 indicadores de clasificación: productivos, usos de la tierra, infraestructura y equipos, suplementación alimenticia y disponibilidad de agua en las fincas; ii) la segunda fase fue el análisis de información; se realizaron análisis de conglomerados con el método de Ward y una distancia de Gower para definir las tipologías de fincas; ANOVAS y pruebas de comparación de medias de Duncan para seleccionar las variables cuantitativas, finalmente tablas de contingencias y análisis de correspondencia para variables cualitativas. Se obtuvieron 3 tipologías de fincas: fincas con nivel tecnológico alto (FNTA), fincas con nivel tecnológico medio (FNTM) y fincas con nivel tecnológico bajo (FNTB). El grupo FNTA se caracterizó por una mayor disponibilidad de infraestructura y equipos, alimentación basada en pastos mejorados, pastos de corte y suplementos elaborados en finca (ensilajes) y externos de la finca (concentrados), con una producción promedio de leche de 139,96 l /finca/día y 4,54 l leche/vaca/día; 168,17 l leche/finca/día y 7,04 l leche/vaca/día, durante época seca y lluviosa respectivamente. Este grupo se caracteriza por proteger fuentes de agua con bosques naturales (79,17%) y tener mayor disponibilidad de agua durante época seca. Las FNTM se caracterizaron por poseer mayor proporción de pastos de cortes, alimentación basada en pastos mejorados y más nacientes de agua, además cuentan con producciones de 41,24 l leche/finca/día y 2,88 l leche/vaca/día; 77,68 l leche/finca/día y 5,08 l leche/vaca/día, durante época seca y lluviosa respectivamente. Las fincas FNTB utilizan como principal alimentación las pasturas naturales, la ganadería presenta el mayor aporte al ingreso total de la finca (84,46%) y la producción promedio de leche es de 22,67 l leche/finca/día y 2,33 l leche/vaca/día; 46,2 l leche/finca/día y 4,88 l leche/vaca/día, durante época seca y lluviosa respectivamente.

The present study was conducted on cattle farms located by the river La Villa basin, during the dry season (January to April) and rainy season (May to July). The average rainfall ranges from 1000-2400 mm annually and 91% of the rainfall occurs between December and April. The maximum temperature in the upper part of the basin is 29.6°C and minimum 19°C. In the middle basin maximum temperatures is 31.9°C and the minimum recorded is 20°C, while, in the lower basin the maximum temperature is 34.2°C and minimum is 20.7°C. In the first article, cattle farms were classified according to the level of technology presented. The classification is performed in two phases. The first phase included existing data. The sample was 211 farms, which was obtained from a population of 3116 cattle producers. Through literature review and criteria of technical equipment classification IDIAP five indicators were defined: production, land use, infrastructure and equipment, nutritional supplementation and water availability at the farm. The second phase was the analysis; cluster analysis with Ward's method and a distance of Gower were performed to define the types of farms. ANOVAS testing and comparison of means by Duncan were used to select quantitative variables, final contingency tables and correspondence analysis for qualitative variables. We obtained 3 types of farms: Farms with high technological level (FHTL), farms with medium technology level (FMTL) and farms with low technological level (FLTL). The FHTL group was characterized by a greater availability of infrastructure and equipment, based on improved pasture and feed supplements. They had an average milk production of 139.96 l milk/farm/day and 4.54 l milk/cow/day, 168.17 l milk/farm/day and 7.04 l milk/cow/day during dry and rainy season respectively. They had higher proportion of farms that protect water sources with natural forests (79.17%) and higher water availability during dry season. The FMTL were characterized by higher proportion of pasture cuts and water sources, as well as milk productions on 41.24 l/farm/day and 2.88 l milk/cow/day, 77.68 l milk/farm/day and 5.08 L milk/cow/day during dry and rainy seasons respectively. The FLTL farms used as main power natural pastures, have more contribution of livestock to total farm income (84.46%) and the average milk yield is 22.67 l milk/farm/day and 2.33 l milk/cow/day, 46.2 l milk/farm/day and 4.88 l milk/cow/day during dry and rainy season respectively. The second article calculated the water footprint (HH) of the production of one liter of milk as well as the water footprint per animal unit. These were then classified as farms with high, medium or low technology. 9 farms were selected, 3 farms with high technological level (FHTL), 3 farms with medium technology (FMTL) and 3 farms with low technology (FLTL). To calculate the whole herd of farms (dairy cows, dry cows, calves, bulls, stallions), the Predominant race was crossing Bos indicus × Bos taurus. The variables measured were: animal weight, dry matter content of forages (% MSF), matter intake of animals ( CMS) offered as diet, milk production ( PL ), liters of water used to produce a kilogram of dry forage ( RA / kg / MSF), direct water consumption (CDA ), indirect water consumption (CAI) and water usage ( UdA ). The water footprint per liter of milk and water footprint per animal unit was obtained from the amounts of water consumption, milk production and animal units averages. Then, the average water footprint per farm was calculated based on the water footprint of dairy cows and non-lactating categories water footprint. The results of water consumption and water footprint was analyzed by lineal model, general and mixed models with different groups and season variances. The water footprint per liter of milk for dry season was 951.31, 1082,96 and 1111,3 l water/l milk in FMTL, FHTL, FLTL farms, whereas in the rainy season was 692.93, 962.76 and 1021.39 l water / l milk in FHTL, FMTL and FLTL farm. The water footprint per animal unit was 1646, 2185 and 2600 l/UA in FMTL, FLTL and FHTL farm and in the rainy season it was 3261.32, 3755.4 and 3832.65 l /UA for FHTL, FMTL and FLTL farm. The average water footprint of times to produce a liter of milk was 845.98 liters of water in Middle Farms with Technology Level, 896.97 liters of water in Farms with High Technological Level and 1022.13 liters of water in Farms with Low Level Technology respectively. Finally, water consumption per farm in terms of l water / UA / day was 3681.75; 3708.27 and 3717.73 for FHTL, FMTL and FLTL groups respectively.