ENVIRONMENTAL INFLUENCE ON THE PRODUCTIVITY OF THE SECOND HONEY HARVEST IN AGUASCALIENTES FROM 1998 TO 2010
INFLUENCIA DEL AMBIENTE SOBRE LA PRODUCTIVIDAD DE LA SEGUNDA COSECHA DE MIEL DE ABEJA EN AGUASCALIENTES DE 1998 A 2010
/ pages 159-165
We analyzed the effect of temperature, rainfall, rainfed harvested area and labor applied on honey production in the second honey harvest season (1998-2010), in Aguascalientes. This analysis was performed by modeling a Cobb-Douglas function by twostage least squares. The criteria for variables selection was based on works concerning the henology of bees, and the predominant source of nectar, as well as, the design of the production function. We obtained a model based on each apiary (78 apiaries) annual data, considering 4,901 beehives, with a R2 in differences of 0.71. The honey per beehive production elasticity, in relation to rainfall, rainfed harvested area and labor were positive, and negative regarding last year honey production, and temperature. The weather and labor per beehive were the factors responsible for yield variability of honey per beehive.
SITE INDEX FOR Pinus greggii Engelm. PLANTATIONS IN METZTITLÁN, HIDALGO, MEXICO
ÍNDICE DE SITIO PARA PLANTACIONES DE Pinus greggii Engelm. EN METZTITLÁN, HIDALGO, MÉXICO
/ pages 167-176
Productivity indices are essential to sustainable forest management planning. Site Index is the primary method used to classify the quality of forest sites. However, this information is not available to aid in the planning of silvicultural interventions for most forest stands and plantations. Therefore, the objective was to estimate the site index for forest plantations of Pinus greggii Engelm., which were already established in the mountainous region of the municipality of Metztitlán, Hidalgo. Schumacher, Chapman-Richards and Weibull functions were fitted to 233 age-height data pairs obtained from stem analysis. Based on the lowest value of the mean square error, the highest R2 value and the distribution of residuals, the Schumacher model was selected for the construction of the guide curve and the families of anamorphic and polymorphic curves. Five site index labels were established for heights of 12, 14, 16, 18 and 20 m with site qualities of V, IV, III, II and I, respectively. A good representation of dominant height growth as a function of age was achieved given that all conditions existing within the plantations were considered in the models.
EQUATIONS FOR ESTIMATING GROSS CALORIFIC VALUE OF WOOD FROM FOUR TREE SPECIES
ECUACIONES PARA ESTIMAR EL PODER CALORÍFICO DE LA MADERA DE CUATRO ESPECIES DE ÁRBOLES
/ pages 177-186
The objective of this study was to fit regression equations that express the gross calorific power (GCV) of wood from four tree species: Acacia mearnsii De Willd., Eucalyptus grandis Hill, Mimosa scabrella Benth. and Ateleia glazioviana Baill. The backward variable selection procedure was used to formulate GCV equations according to the volatile matter content (VMC), ash content (AC), fixed carbon content (FCC) and organic matter content (OMC). Sample collection was performed one year after planting to determine such variables. All equations performed well: fitted values for the coefficient of determination was greater than 82 %, standard error of the estimate was less than 1.1 % and distribution of residuals was adequate. The equations involving only the VMC for A. mearnsii, AC for E. grandis and A. glazioviana, and elements of proximate analysis for M. scabrella are just as effective at estimating GCV as other equations that include a greater number of independent variables.
SELECTION OF ENVIRONMENTAL PREDICTORS FOR SPECIES DISTRIBUTION MODELING IN MAXENT
SELECCIÓN DE PREDICTORES AMBIENTALES PARA EL MODELADO DE LA DISTRIBUCIÓN DE ESPECIES EN MAXENT
/ pages 188-201
Prior to conducting the modeling of the potential distribution of a species, it is advised to make a pre-selection of covariables because redundancy or irrelevant variables may induce errors in most modeling systems. In this study, we propose an automated method for a priori selection of covariables used in modeling. We used five typical species of the Mexican flora (Catopheria chiapensis, Liquidambar styraciflua, Quercus martinezii, Telanthopora grandifolia and Viburnum acutifolium) and 56 environmental covariables. Presence-absence matrices were generated for each species and were analyzed using logistic regression, and the resulting model of each species was evaluated via a bootstrap resampling. We modeled the distribution of five species using maximum entropy and employed three sets of environmental covariables. The precision of the models generated was evaluated with the confidence intervals for each receiver operating characteristic (ROC) curve. The confidence intervals of the resulting ROC curves showed no significant difference between (P < 0.05) the three predictive models generated; nevertheless, the most parsimonious model was obtained with the proposed method.
BORON FERTILIZATION IN PLANTATIONS OF Eucalyptus urophylla S.T. Blake in TABASCO
FERTILIZACIÓN CON BORO EN PLANTACIONES DE Eucalyptus urophylla S. T. Blake en TABASCO
/ pages 204-213
This study was carried out in commercial Eucalyptus urophylla plantations owned by the Forestaciones Operativas de México, S.A. de C.V. (FOMEX) company in Huimanguillo, Tabasco, Mexico, to determine the effect of boron (B) fertilization on the growth of this species. Follow-up was given to 199 E. urophylla trees that received different B doses (0, 6 and 12 g·tree-1) during establishment. Tree diameter and height were measured at 1.5, 4.5 and 11 years of age. Destructive sampling was performed by separating the bole, branches, twigs + leaves to quantify biomass and its distribution. In addition, total leaf nutrient content was evaluated and the response to B application was measured using vector analysis. Results showed that B fertilization favored growth in height and wood volume, but this effect was not observed in aerial biomass accumulation. Vector analysis showed increased leaf P, K and Ca content when B was applied at a dose of 6 g·tree-1. At the higher dose (12 g·tree-1), foliar biomass was lower, presenting similar net nutrient contents and concentrations to those of the smallest leaves.
PROVISIONAL ALTITUDINAL ZONING OF Abies religiosa IN AN AREA NEAR THE MONARCH BUTTERFLY BIOSPHERE RESERVE, MICHOACÁN
ZONIFICACIÓN ALTITUDINAL PROVISIONAL DE Abies religiosa EN UN ÁREA CERCANA A LA RESERVA DE LA BIÓSFERA DE LA MARIPOSA MONARCA, MICHOACÁN
/ pages 215-225
The aim of this study was to determine whether there is a morphological differentiation (as an indicator of genetic variation) among populations of Abies religiosa, in order to delineate an altitudinal zoning to decide seed movement in reforestation programs. Branches and cones of 11 individuals of 15 A. religiosa populations on San Andrés Mountain, Municipality of Hidalgo, Michoacán (near the Monarch Butterfly Biosphere Reserve), along an altitudinal transect (2,850- 3,550 m, a population every 50 m of altitudinal difference) were collected and analyzed for morphological traits. The results indicate a significant morphological differentiation among populations along the altitudinal gradient: low-altitude populations have shorter needles and longer cones than high-altitude populations. It is suggested to delineate three provisional altitudinal zones with the following limits: 2,800 to 3,050 m, 3,050-3,300 m and 3,300-3,550 m. Ignoring climate change, it is suggested to reforest each altitudinal zone using seedlings originated from the same seed zone. Considering climate change, it is suggested to conduct an altitudinal assisted migration, by planting sites in the zone immediately above the zone from where seed were collected.
ISOLATION AND IDENTIFICATION OF STEROLS IN A COMMERCIAL STRAIN OF Pleurotus sp.
AISLAMIENTO E IDENTIFICACIÓN DE ESTEROLES DE UNA CEPA COMERCIAL DE Pleurotus sp.
/ pages 227-235
Five compounds in a commercial strain of the mushroom Pleurotus sp. were obtained from ethyl acetate and methanol extracts. The compounds were isolated using techniques such as column and thin layer chromatography. The following sterols were identified by 1H NMR spectroscopy: 1) ergosta-5,7,22-trien-3β-ol (ergosterol), 2) 5α, 8α-epidioxy-22E ergosta-6, 22-dien-3β-ol (ergosterol peroxide), 3) 3β,5α,6β,9α-tetrahidroxiergosta-7,22 dieno, 4) 3β, 5α, 6β, 9α-tetrahydroxyergosta-7, 22-dien and 5) 3β, 5α, 9α trihidroxiergosta-7,22-dien-6-one.
SOFTWARE Assofu TO ASSESS ENVIRONMENTAL SOIL FUNCTIONS
SOFTWARE PARA LA EVALUACIÓN DE LAS FUNCIONES AMBIENTALES DE LOS SUELOS (Assofu)
/ pages 237-249
The interpretive analysis of soil functions is essential for its proper use and handling. The evaluation of these soil functions evolved from the theoretical to the practical with the outlines of the method “Technique for soil evaluation and categorization for natural and anthropogenic soils”. On other hand, the soil interpretive models oriented to agriculture and environmental objectives, such as MicroLEIS DSS (Land evaluation decision support system for agricultural soil protection) have been the most used in the world, however, few models of soil functions are included in software so its manual handling can lead to errors and inaccuracies. The aim of this work was the development of a software system includes the advantages and benefits of MicroLEIS DSS and TUSEC models considering a more user-friendly. Assofu software stored as input the properties of soil profiles, and based on this information systematized assessments applying soil functions.
REGIONAL DISTRIBUTION OF RED BROCKET DEER (Mazama temama) IN PUEBLA, MEXICO
DISTRIBUCIÓN REGIONAL DEL VENADO TEMAZATE ROJO (Mazama temama) EN EL ESTADO DE PUEBLA, MÉXICO
/ pages 251-260
The aim of this study was to determine the distribution of red brocket deer (Mazama temama) in Puebla, through a field sample, based on literature references and interviews with people related to the species. This sampling was performed by linear path quadrants with variable length and width fixed to determine the presence of deer through direct observation (seeing animals) and indirect observation (footprints, feces, bark rubbing or captive animals). The regional distribution was obtained from the information generated at sites that corroborated the presence of temazate, using Geographic Information System (GIS) using the Arc View 3.2 program. The GIS results suggest that the deer is distributed in the Totonacapan and the western area of the Sierra Norte and in the eastern part of the Sierra Negra, covering a total area of 99,410.96 ha. The similarity index (95.2) in both Sierras, by direct evidence or traces, indicates presence and similar distribution of red brocket deer, agreeing with the results of the GIS. We conclude that the regional distribution of red brocket deer in Puebla is concentrated in 42 municipalities of the Sierra Norte and east of the Sierra Negra.
CAPACITY OF PHENOLOGICAL DATA DERIVED FROM CYCLOPES LAI FOR THE YEAR 2000 TO DISTINGUISH LAND COVER TYPES IN THE STATE OF MICHOACÁN, MEXICO
CAPACIDAD DE LOS DATOS FENOLÓGICOS DERIVADOS DE CYCLOPESLAI DEL AÑO 2000 PARA DISTINGUIR LOS TIPOS DE COBERTURA EN EL ESTADO DE MICHOACÁN, MÉXICO
/ pages 261-276
The capacity of the phenological data of the CYCLOPES project LAI series for the year 2000 to distinguish general vegetation types (evergreen forest, deciduous forest, crops and pastureshrubland) in Michoacán, Mexico, was explored. Using the TIMESAT program, 11 phenological variables of each 1-km pixel of that series were extracted. The behavior of each variable was analyzed using the INF2000 map as a reference. The main differences relate to the deciduous or evergreen character of the vegetation. The 11 variables were reduced to five principal components (98% of the variance) to make an unsupervised classification of 250 phenological classes or groups. Each class was associated with one of the cover types, with a criterion of maximum area matched with the INF2000 reference map, in order to construct the CYCL2000 cover map. Comparing the two maps yielded modest results, with 63 % total accuracy. Deciduous forests were better identified (80.1 % of pixels correctly identified and 62.1 % correctly classified), followed by evergreen forests (74.1 %, 69.9 %), crops (62.9 %, 61.1 %) and pasture shrubland (16.9 %, 52.3 %). The relatively good identification of forests shows that this approach could be used to estimate deforestation.
Cratylia argentea: A POTENTIAL FODDER SHRUB IN SILVOPASTORAL SYSTEMS. YIELD AND QUALITY OF ACCESSIONS ACCORDING TO REGROWTH AGES AND CLIMATIC SEASONS
Cratylia argentea: UN ARBUSTO FORRAJERO POTENCIAL EN SISTEMAS SILVOPASTORILES. RENDIMIENTO Y CALIDAD DE ACCESIONES SEGÚN LAS EDADES DE REBROTE Y ESTACIONES CLIMÁTICAS
/ pages 277-293
In silvopastoral systems, high nutritional quality shrub legumes represent an alternative to shortage of grasses in dry periods of the year. The effect of different regrowth ages (6, 9, 12 and 15 weeks) in three climatic seasons (rainy, winter and dry seasons, 2007-2008) of four Cratylia argentea accessions (18516, 18666, 18668 and 18676) were evaluated in Veracruz, Mexico, for dry matter yield (DMY), neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin (Lig), crude protein (CP) and in situ DM degradation (ISDMD). Dry matter yield (mean ± standard error) was affected by season and regrowth age, but not by accession or interactions. The dry season showed the largest DMY (3632 ± 306 kg·ha-1), representing 45 % of total forage yield, followed by the rainy (33 %, 2615±188 kg·ha-1) and winter (22 %; 1733 ± 61 kg·ha-1) seasons. For NDF, ADF, Lig and CP, statistical effects were found for regrowth age in all three seasons. The largest ISDMD occurred in the rainy and dry seasons, reaching average values of 66 and 65 % at 72 h of incubation, respectively. The dry season was the best period for DMY and ISDMD, making Cratylia argentea a reliable feed resource for silvopastoral systems.