Universidad Nacional Agraria La Molina. Escuela de Posgrado. Maestría en Economía de los Recursos Naturales y del Ambiente

El objetivo de esta investigación fue estimar el consumo animal óptimo, considerando aspectos biológicos y económicos en condiciones de pastoreo extensivo en la sierra central del Perú. La base de datos se construyó con información proveniente de estudios de perfiles alimentarios de explotaciones ganaderas que permitieron conocer el efecto de la carga animal sobre la dinámica de vegetación y el nivel de remoción de la misma para vacunos.  Se aplicó el modelo bioeconómico de Gordon y Schaefer, el enfoque de carga animal segura y máxima de Noy - Meier y el método de Galarza y Collado para la estimación del precio sombra de los recursos naturales. Se estimó que la carga animal óptima expresada en unidad animal mes por hectárea (UAM/ha) fue de 2,26 cuando se empleó los precios de mercado. El nivel de carga óptima tiene asociado un stock de biomasa disponible de 4587,32 k...

Moderate resolution imagery (MODIS) data from the Normalized Difference Vegetation Index (NDVI) can be used to estimate aboveground biomass at large spatial scales; however, validation of the information with fieldwork is required to make more accurate grassland vegetation predictions. The study was conducted in three districts of the central highlands of Peru. In total, 153 grass samples (high grassland and low grassland) were collected after reading NDVI in situ within a pixel of 250x250 m, with a frequency of three months during a three year period. Satellite images were downloaded from the MODIS sensor to obtain the NDVI. The NDVI-MODIS values were calibrated with the NDVI registered in situ, using regression models. The calibrated equations modelled the dynamic trends of vegetation between 2000 and 2018 for the central highlands. The NDVI in situ of the low grassland ranged between ...

The aim of this study was to determine the effect of the age of the quail (Coturnix coturnix japonica) on the morphometry of the egg and the size of the bird at birth. In total, 227 fertile quail eggs of three ages (15, 19 and 34 weeks) were used. Egg weight (g), shape index (%), hatching weight (g), body weight/egg weight ratio, and hatching length (mm) were evaluated using a completely randomized block design. There were no significant differences between ages with egg weight. Egg shape index was significantly higher in 15-week-old birds (79.50±0.34%) than in 34-week-old birds (78.0±0.36%; p<0.05). Birth weight was greater for 34-week-old birds (7.91±0.08 g) compared to 15-week-old birds (7.63±0.07 g; p<0.05). Live weight/egg weight ratio was significantly different between breeders of 15 (68.9±0.37%) and 34 weeks (70.4±0.41%), while quail length at hatch was greater in 19-...

Tillage conservation practices (CA), traditional agriculture (TA), and liming influence soil properties and crop yield. However, it is essential to demonstrate which tillage and liming practices improve soil properties and forage corn yield. This study compared soil properties and forage corn production in two tillage systems with the addition of dolomite and lime, which formed four treatments. The tillage in the first three days surpassed the TA soil CO2 emission, with 64.8% more CO2 than in the CA soil, and the TA hydraulic conductivity and bulk density were more suitable than those in the CA soil. The CA soil had 233 earthworms m−2 more than in TA. The TA green forage corn yielded 6.45 t ha−1 more than in CA, with a higher P, Ca, and Mg foliar content than in CA, but in the CA, the foliar N and K were higher than in TA. The liming increased soil cations (except K), highlighting th...