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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]

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Biometric systems are the basis of forest management and consist of a set of equations that describe the relationships between forest attributes and dendrometric variables. A systematic review of the state of the art of biometric systems in Mexico was carried out by a Mexican consortium (10 researchers), covering a period of 50 years ca (1970–2019), using the main scientific literature delivered by a systematic search (WoS, Scopus, Scielo, Redalyc) and a targeted search (theses, technical reports, etc.). A single selection criterion was established for the inclusion of information in the analysis: the document had to present at least one of the equations of interest. We found 376 documents containing 2524 equations for volume (69%), diameter (11%), height (9%) and site index (11%). These equations were developed for forest species mainly from temperate regions (88%), such as pine (66%) and oak (9%). Consequently, the Mexican states with the highest number of equations were Durango (28%), Chihuahua (17%), Hidalgo (13%) and Oaxaca (8%). Although large, the number of equations identified concentrated on a relatively small number of models: Schumacher & Hall and Fang et al. for volume; Chapman-Richards and Schumacher for site index and diameter; and Chapman-Richards and the allometric equation for height. An analysis of model fit, measured through R2, showed that, on average, the volume, diameter and site index models show high fit (R2 = 0.96), although this pattern was more consistent in the volume models. Publication bias was evaluated by means of a funnel plot analysis, with no apparent bias identified. A limitation of our study is that the information obtained is not updated to the present year; however, the 50-year trends allow us to assume that no recent significant changes in the patterns exist. Finally, we highlight the need to assess the predictive ability of the models to ensure accurate estimates to support better forest management decisions. [ABSTRACT FROM AUTHOR]

Copyright of Estudios Demográficos y Urbanos is the property of El Colegio de Mexico AC and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article discusses the features, perspectives and challenges that define the forest regulation and its problems in Mexico. It is part of the evolution of forest regulation in our country, to analyze the elements and definitions that have influenced the regulation and legal practice in forest. Although already have implemented legislation the different elements that make up a new model of forest regulation oriented towards sustainable forest development, it is concluded that control mechanisms and effective enforcement of the legislation; it takes in not establishing clearly the objectives of each of the forest functions, which generates in legal practice, a contradiction between production and conservation of forest resources policies. [ABSTRACT FROM AUTHOR]