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Soil organic carbon (SOC) is of most importance for the development of all ecosystems, specifically carbon forest stock, as it is affected by climate, tree species and forest management. The aim of this study is to determine SOC changes in an Umbrisol under forest management in a temperate forest in Mexico. Three silvicultural forest stands were analyzed (Clear cutting, Seed-trees and Selection) and compared with a Post-fire area and a Reference stand. At each stand, 4 composite soil samples were collected at two depths (0–20 and 20–40 cm) to determine SOC; the values obtained from these samples were then used as inputs for the RothC 26 model. The ANOVA indicated differences in the SOC between stands and depths. Seed-trees showed highest content of SOC (0–20 cm), with an increase of 63% with respect to Reference. At depth 20–40 cm, Clear cutting presented the highest SOC, with increase rates above 100% with respect to Reference. Differences in the SOC can be attributed to litter deposition from forest harvesting and fires. Forest management contributes to improving and increasing the capacity of Umbrisols as carbon reservoirs. The modeled scenarios for both depths showed that SOC reservoirs reach an equilibrium after 50–60 years. [ABSTRACT FROM AUTHOR]

In the small ruminant sector, there is a great interest in measuring and improving their production systems and their environmental performance, since its great adaptability and inhabits a wide variety of ecosystems, with a great biodiversity of food resources, grazing in turn, generates economic-productive and environmental benefits. However, unplanned management and overexploitation of the natural resources of these areas have caused erosion, water depletion and even desertification, in the same manner intensive production systems and intensive agriculture that feeds these farming systems. To compare scientific innovations in the sustainability of the different production systems of small ruminants a bibliometric analysis was carried out to describe the advantages and disadvantages of the management of extensive, semi-intensive and intensive-stable production systems in the sustainability of small ruminants. There is concern in society about the environmental impact of animal production systems and that these have been carried out in a sustainable way. This trend influences the production of sheep, goats, and white-tailed deer, which are develop in intensive, semi-extensive and extensive systems. Due to the pressure to increase the volume and efficiency of production and to cope with demand, intensive systems are best suited, but face greater environmental problems such emission of greenhouse gases (GHGs), which contribute to global warming and animal welfare problems. On the other hand, semi-extensive and extensive systems also emit GHGs, however are associated with greater animal welfare and cleaner production. However, are affected by seasonal variations for forage production to maintain production levels. [ABSTRACT FROM AUTHOR]

Since the XVI century, the Chihuahuan desert has been a grazing area. This area has ecological and economical significance for the country; however, overgrazing has caused changes in the physical and hydrological properties of the soil. These changes were evaluated on microphyllus desert scrublands (MDM) and rosette desert scrublands (MDR) in Coahuila, Mexico. The rehabilitation techniques were an aerator roller during 2004, 2008 and 2011, and natural fires. The hypothesis was that both techniques promote the increase of the soil's organic matter (MOS), water infiltration, and decrease soil compaction. A bifactorial experimental design was used which consisted of 10 treatments: 1) control (MDMt and MDRt); 2) aerator roller, applied in 2004 (MDMRA04 and MDRRA04); 3) 2008 (MDMRA08 and MDRRA08); 4) 2011 (MDMRA11 and MDRRA11); and, 5) burned area, 2011 (MDMIN11 and MDRIN11). The following variables were analyzed: useful water (AU), coefficient of permeability, electrical conductivity, apparent density, water infiltration on the soil, soil organic matter, soil reaction, mechanical resistance to penetration, and soil texture. Five treatments were applied on both types of vegetation, and the analysis of variance showed significant differences in all the variables, except for the AU percentage. The RA11 and IN11 treatments' MOS content doubled on both types of vegetation, with regard to the content observed on the control treatments. Permeability decreased by 5, 82, 45, 48, and 12 %, on the MDMRA04, MDMRA08, MDMRA11, MDRRA08, and MDRIN11 treatments, respectively, and increased by 6 and 2 % on the MDMIN11 and MDRRA04 treatments, in relation to control. During the first 3 years, the aerator roller increased MOS and decreased soil compaction. Therefore using the aerator roller is a periodic management option depending on the soil variables' state, in relation with its use. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the monthly composition of the minerals Ca, P, K, Mg, Cu, Fe, Mn and Zn in five shrub species that are consumed by small ruminants in the semi-arid regions of northeastern Mexico. Leaves samples of shrub species; Celtis pallida, Croton suaveolens, Forestiera angustifolia, Guaiacum angustifolium and Parkinsonia aculeata were randomly collected during twelve consecutive months from July 2018 to June 2019 in two sites, located in Linares and Los Ramones counties, in the state of Nuevo Leon, Mexico. Mineral content was analyzed using an atomic absorption spectrophotometer, while phosphorus was measured by the colorimetry method. The Linares county showed the highest content of macro- and micro-minerals. Among species, C. pallida showed the highest values of macrominerals and P. aculeata content of micro-minerals was highest. Ca (total mean = 40.0 g kg-1 DM), K (15.4 g kg-1), Mg (3.7 g kg-1), Fe (87.2 mg kg-1), Mn (35.5 mg kg-1) were available in adequate quantities, while P (1.3 g kg-1 DM), Cu (6.4 mg kg-1) and Zn (17.7 mg kg-1) were found deficient. Shrub species in this study can be considered as a good source of Ca, K, Mg, Fe and Mn except in C. suaveolens. However, P, Cu and Zn must be supplemented. [ABSTRACT FROM AUTHOR]

In the present study, an experiment was conducted to evaluate the effect of Lippia palmeri S. Watson and the nutrient synchronization of four goat diets by using a model of repeated measures experimental design, evaluating the variables of milk production, feed consumption and food conversion. Three landrace goats were used per treatment to assess the differences between diets. Goats were fed over a period of 3 months with diets consisting of a controlled consumption of the same feed. According to the results, the treatments showed no significant differences (p>0.05) in the three variables studied. Goats fed with ASYNC with ORE (T1) tended to achieve higher feed consumption compared to other treatments. Regarding milk production, it was observed that there was a variation between treatments, where ASYNC without ORE (T2) showed a higher production in month 1, ASYNC with ORE (T1) in month 2 and SYNC with ORE (T4) in the last month tested. Milk production ranged from 0.543 kg/day to 1.027 kg/day, food consumption varied from 0.821 kg/day to 1.588 kg/day and food rejection from 0.036 kg/day to 0.259 kg/day. The results suggest that the inclusion of Lippia palmeri S. Watson in the diet of early lactating dairy goats can be used as a natural additive, to support the production in seasons of feed shortage in rangelands of arid and semi-arid regions. [ABSTRACT FROM AUTHOR]

Seasonal xylem water potentials (Ψ, MPa) and their relationship to soil water content and evaporative demand components were studied in the shrub speciesAcacia amentacea, Celtis ehrenbergiana, Forestiera angustifolia, andParkinsonia texanavar.macra. Predawn (Ψpd) and midday (Ψmd) water potentials were estimated at 15 days intervals, between January 15 and October 30, 2009 using a Scholander pressure bomb at 06:00 h (predawn) and 14:00 h (midday), respectively. During the humid period, Ψpd ranged from −0.30 MPa (C. ehrenbergiana), to −0.90 MPa (P. texana). In contrast, over the driest period, Ψpd varied between −2.18 (P. texana) and −3.94 MPa (F. angustifolia). At midday,P. texanaandF. angustifoliashowed the highest (−1.14 MPa) and lowest (−3.38 MPa) Ψ values, respectively. Average soil water content accounted for 35 to 70% of the variation in predawn Ψ. Furthermore, both Ψ reflected the environmental conditions, as indicated by typical correlations observed. The studied shrub species exhibited what seem to be different strategies to avoid damage caused by drought. Thus,P. texanabehaved rather as an isohydric plant able to deal well with severe, but short periods of drought. Under exceptionally dry environmental conditions, Ψpd undercut Ψmd values. Similar observations have been made by researchers studying plants in dry ecosystems. All studied native species are recommended for reforestation of the Tamaulipan shrublands, althoughC. ehrenbergianaandF. angustifoliaseem to have limited tolerances for extreme water stress. [ABSTRACT FROM AUTHOR]

Background: Trough collections of plants and interviews with 110 individuals, an ethnobotanical study was conducted in order to determine the knowledge and use plant species in Rayones, Nuevo Leon, Mexico. The aim of this study was to record all useful plants and their uses, to know whether differences exist in the knowledge about the number of species and uses between women and men, and to know if there is a correlation between the age of individuals and knowledge of species and their uses. Methods: A total of 110 persons were interviewed (56 men, 56 women). Semistructured interviews were carried out. The data were analyzed by means of Student t test and the Pearson Correlation Coeficient. Results: A total of 252 species, 228 genera and 91 families of vascular plants were recorded. Astraceae, Fabaceae and are the most important families with useful species and Agave and Opuntia are the genera with the highest number of useful species. One hundred and thirty six species are considered as medicinal. Agave, Acacia and Citrus are the genera with the highest number of medicinal species. Other uses includes edible, spiritual rituals, construction and ornamentals. There was a non-significant correlation between the person's age and number of species, but a significant very low negative correlation between the person's age and number of uses was found. Conclusions: Knowing their medicinal uses is an important issue for the people of Rayones. Boiling and preparing infusions are the main ways of using plants by residents. The leaves, the branches, and the fruits are the most commonly used parts. Almost 18% of the flora is used for wood and construction purposes. Several uses such as cosmetic, shampoo, firming skin tonics and health hair products recorded in Rayones has not been reported for other areas in the state of Nuevo León. In Rayones, women have a greater knowledge about plants and their uses than men, particularly, medicinal plants, but, men have a greater knowledge about wood and construction species. [ABSTRACT FROM AUTHOR]

During the summer of 2007, a study of the status of trees and woody vegetation was performed at four sites, in the state of Nuevo Leon, Mexico. Site one (S1, Bosque Escuela) was located at 1600 m elevation in Iturbide county. Sites S2 (Crucitas, 550 m), S3 (Campus, 350 m) and S4 (Cascajoso, 300 m) were located in Linares county. In each site, 10 random plots (10 m x 10 m) were laid out, and relative abundance, relative dominance and relative frequency were estimated. In addition, dasometric parameters such as height and crown diameter were determined. Plant diversity was estimated by the Shannon- Wiener index, and similarity between sites was calculated using the Jaccard index. A total of 13710 individual plants belonging to 28 families were registered. Leguminosae had the highest number of species (10) followed by Fagaceae (4), Rutaceae (4), Euphorbiaceae (3), Oleaceae (3), Cupressaceae (3), Rhamnaceae (2) and Verbenaceae (2). Eighteen families included only one species. The site with higher and lower Shannon index was Cascajoso (2,08) and Bosque Escuela (1,64), respectively. The Jaccard index showed similarity among species only among S2, S3 and S4 sites. The plant species more frequent were: in S1 Quercus canbyi, Pinus pseudostrobus and Rhus pachyrranchys (11,9%); in S2 Havardia pallens (9,9%); in S3 Havardia pallens and Forestiera angustifolia (9,8%) and in S4 Acacia rigidula, Cordia boissieri and Karwinskia humboldtiana (9,8%). S2 and S3 were the sites with the greatest species diversity, perhaps as a result of higher rainfall. [ABSTRACT FROM AUTHOR]