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Objective: To analyze the changes in land-use and vegetation (LUV), from 1985 to 2014, in the sites in northern Mexico where 16 pine trees listed in the NOM-059-SEMARNAT-2010 are collected. Design/Methodology/Approach: Based on consultations in botanical collections, a georeferenced database of the species under study was developed. A point coverage was created to which LUV vector information from Series I (1985) and VI (2014) was added. Subsequently, LUV class changes were identified during the evaluation period through spatial analysis and geoprocessing. Results: A total of 2,242 georeferenced records of pine species were obtained. Fifty percent of the pine records consulted in collections with Series I information belong to other non-primary forest categories of LUV, while with Series VI information with this condition rose to 58.7%. Consequently, in the study period major changes occurred in the conversion of primary forests to agricultural lands, pasture, secondary vegetation in coniferous and oak forests, and mainly urban areas. Limitations/Implications: The availability of larger-scale cartographic material limited the generation of a risk analysis study about the changes and threats to forest conservation. Findings/Conclusions: The number of collection sites registered in coniferous forest, scrubland, and primary oak forest in Series I —which are now agricultural lands, water bodies, pastures, and urban areas— was significantly lower than in Series VI. [ABSTRACT FROM AUTHOR]

Water quality is a relevant factor for production of forest species, but it is not always taken into account in nurseries in Mexico. One of the parameters of water quality is its acidity. The objective of this work was to study the response in morphology and concentration of ions and cations in leaf tissue of Pinus cembroides Zucc., to different water pH and concentrations of compounds in fertigation solutions. Plants were cultivated in a nursery in 170 cm3 containers with a substrate made of peat moss (40 %), vermiculite (30 %) and agrolite (30 %). The experimental design was completely randomized blocks with two factors and two levels: 1) pH of irrigation water (8 and 5.5); 2) fertilization (ppm): establishment (50-123-73 of N, P, K for both levels), growth (100-22-83 and 150-33-125) and finalization (15- 41-109 and 30-82-218); these levels of fertilization were denominated low and high. The effect of factors and their interaction was determined with an ANOVA (p⩽0.10). The morphological variables and quality indexes evaluated were height, diameter, shoot dry weight, root dry weight, Dickson quality index, shoot/root ratio, lignification index, slenderness index and leaf nutrient concentration. There was no response in terms of morphological variables or indexes. There was, however, a response in leaf nutrient concentration. The highest leaf concentration of K (p⩽0.001) was obtained with high fertilization at both levels of pH, and the highest concentration of Mn with higher fertilization without adjusting pH (8.0). The highest concentrations of Ca (p⩽0.092), Mg (p⩽0.074), and Cu (p⩽0.093) occurred with high fertilization and pH=5.5, and that of Zn (p⩽0.001) was with low fertilization and adjusted pH. There were interactions between fertilization and water pH for K (p⩽0.005), Ca (p⩽0.1) and Zn (p⩽0.039). The highest nutrient concentrations were obtained with water pH=5.5 and high fertilization. [ABSTRACT FROM AUTHOR]

La calidad del agua es un factor relevante para la producción de especies forestales, pero no siempre se toma en cuenta en viveros de México. Uno de los parámetros de calidad de agua es su acidez. El objetivo de esta investigación fue estudiar la respuesta en la morfología y en la concentración de iones y cationes en el tejido foliar de Pinus cembroides Zucc., a diferentes niveles de pH de agua y concentraciones de compuestos en las soluciones de ferti-irrigación. Las plantas fueron cultivadas en vivero, en contenedores de 170 cm3, con sustrato a base de turba de musgo (40 %), vermiculita (30 %) y agrolita (30 %). El diseño experimental fue en bloques completamente al azar, con dos factores y dos niveles por factor: 1) pH del agua de riego (8 y 5.5); 2) fertilización (ppm): establecimiento (50-123-73 de N, P, K para ambos niveles), crecimiento (100-22-83 y 150-33-125), y finalizador (15-41-109 y 30-82-218); estos niveles de fertilización se denominaron bajo y alto. El efecto de factores y su interacción fue determinado con un ANDEVA (p⩽0.10). Las variables morfológicas e índices de calidad evaluados fueron: altura, diámetro, peso seco aéreo, peso seco de raíz, índice de calidad de Dickson (ICD), relación parte aérea/raíz, índice de lignificación, índice de esbeltez y concentración nutrimental foliar. No hubo respuesta en variables morfológicas ni en índices, pero sí en concentración nutrimental foliar. La mayor concentración foliar de K (p⩽0.001) fue con la fertilización alta en ambos niveles de pH, y la de Mn con fertilización alta y sin ajuste de pH (8.0). Las mayores concentraciones de Ca (p⩽0.092), Mg (p⩽0.074) y Cu (p⩽0.093) ocurrieron con fertilización alta y pH=5.5, y la de Zn (p⩽0.001) fue con fertilización baja y pH ajustado. Hubo interacciones entre fertilización y pH del agua para K (p⩽0.005), Ca (p⩽0.1) y Zn (p⩽0.039). Las mayores concentraciones nutrimentales fueron para agua con pH=5.5 y la fertilización alta. [ABSTRACT FROM AUTHOR]