Silvopastoral systems have great potential for storing carbon because of carbon assimilation in tree woody biomass, carbon input through litterfall and below‐ground carbon turnover. In this study, we ...quantified and compared the carbon stocks at livestock ranches in Tabasco, Mexico, containing either scattered trees in grazing pastures (STP) or grass monocultures. Sampling plots were randomly established at each ranch where the above‐ and below‐ground carbon stocks, carbon input from litterfall, grass production and arboreal biomass growth were measured. We found that silvopastoral systems stored an average of 257.45 Mg ha−1 of soil organic carbon (SOC) compared to 119.17 Mg SOC ha−1 at grass monoculture ranches (to 30 cm depth); silvopastoral systems also stored 44.64 Mg C ha−1 in wood biomass; and, grass monocultures had greater cumulative grass biomass production. Overall, it is concluded that livestock ranches in Tabasco, Mexico, with scattered trees in grazing pastures stored 58.8% more carbon than those grass monocultures, with carbon stocks of 327.01 Mg C ha−1and 134.47 Mg C ha−1, respectively. The results are useful for land management decision making for sustainable livestock systems framed in the Sustainable Development Goals (SDGs).
This study aimed to quantify the dynamics of soil CO2 fluxes in two silvopastoral systems based on Leucaena leucocephala, one associated with Panicum maximum (L + P) and another with Cynodon ...plectostachyus (L + C). We measured CO2 fluxes fortnightly during the dry and rainy seasons in the morning and the afternoon, with an infrared gas analyzer. Simultaneously, we measured soil temperature, soil moisture, ambient temperature, and relative humidity. Soil CO2 fluxes ranged from 6.0 ± 0.14 to 6.1 ± 0.12 µmol CO2/m2/s but no statistical differences were observed between systems. Soil CO2 flux in the L + P was 12.5% higher in the rainy season compared with the dry season but the season did not affect the fluxes in L + C. Regarding the diurnal variation, CO2 fluxes were 17.6%–34.8% higher in the morning compared with afternoon measurements. Soil moisture and temperature were higher in L + C, but the ambient temperature and relative humidity showed no statistical differences between systems. In both systems, soil temperature was greater in the afternoon, while the soil moisture and relative humidity were greater in the morning. The diurnal variation of soil CO2 fluxes in silvopastoral systems correlated positively with soil temperature and ambient temperature, but negatively with relative humidity. We concluded that soil CO2 fluxes did not vary between silvopastoral systems but respond differently to the seasons. The results have important implications on the establishment and management of Leucaena‐based silvopastoral systems for the mitigation of soil CO2 fluxes from extensive livestock production lands.
Owing to the increasing extension of land for livestock production, silvopastoral practices have been among the promising approaches to enhance carbon (C) sequestration. However, the extent of C ...sequestration in different silvopastoral systems (SPS) and their relationship with fine root production (FRP) is not well understood. The objective of this research was to evaluate the changes in C storage, FRP, and turnover in a part of tropical SPS. We evaluated above‐ and belowground C storage, FRP and turnover in live fences (LF), dispersed tree (DT) silvopasture, and compared these with open pasturelands (OP) in Southeastern Mexico. We applied the stock change approach to calculate biomass growth rates and the ingrowth monolith method for FRP. Biomass stocks in the same plots are re‐measured over time in the stock change approach. Woody biomass stocks differed significantly between SPS (DT: 37.2, LF: 9.8 Mg ha−1) and the accumulation rates in both SPS were significantly higher than zero (0.2–2.2 Mg ha−1 yr−1). Soil organic carbon (SOC) contents were significantly higher in SPS (LF: 2.4%, DT: 3.1%) compared to OP (1.6%). FRP significantly differed between SPS (LF: 27.8, DT: 45.4, and OP: 9.4 g m−2 yr−1) and correlated positively with SOC content. Higher SOC reduced soil compaction in silvopastoral lands as indicated by lower soil bulk density. The results on C stocks change and fine root dynamics contribute to understanding C sequestration potential of tropical SPS, identifying ecologically sound strategies to mitigate greenhouse gases from the livestock sector, and aid restoration of ecosystem services for degraded pasturelands.
El déficit de forrajes tropicales en la temporada seca requiere de estrategias de alimentación alternas que involucren trasferencia de tecnologías y la conservación de alimentos locales. El objetivo ...fue evaluar la respuesta animal y el costo beneficio ante raciones mixtas con diferentes niveles de inclusión de ensilado de maíz en sistemas de producción doble propósito del sur de Quintana Roo. Se utilizaron nueve vacas lactantes con 152 días en leche en un diseño experimental de cuadrado latino 3 x 3 por triplicado. Las secuencias de tratamiento fueron asignadas al azar con periodos experimentales de 12 días, el tratamiento uno (T1) estuvo conformado por la inclusión del 15% de ensilado maíz; el T2 por 31%, T3 por un 45%. Se evaluó la producción de leche, peso vivo, condición corporal, la composición química de la leche y la viabilidad económica. La producción de leche promedio fue de 4.4 kg vaca−1 día−1, con un contenido de grasa de 3.3% y proteína cruda de 3.4%. El peso vivo promedio fue de 424.6 kg y la condición corporal de 2.3, manteniéndose constante a lo largo del experimento. Solo se observaron diferencias (P < 0.05) para la condición corporal siendo favorable para T3. La incorporación del ensilado de maíz en un 15, 31 o 45% vaca−1 día−1 en las raciones mixtas de vacas doble propósito que producen 4.4 kg leche−1 día−1 no incrementó la producción de leche, pero si tienen un efecto en los costó total de alimentación.
Background: Nitrogen (N) plays an important role within milk production systems (MPS), as an indicator of environmental and economic efficiency. Objective. The objective was to determine utilisation ...of N offered in the ration and estimate GHG from the enteric fermentation and manure management in 12 small-scale dairy farms under two feeding strategies. Methodology. Six farms had their herds in confinement under a cut-and-carry feeding system, and six farms implemented day grazing of mixed pastures, both systems used commercial concentrates as a supplement. Cows in milk production and their replacements were considered in the study. Pasture intake was calculated by difference in dry matter intake, using 3.2 % of live weight as intake factor. The N utilisation was determined by difference between N intake and excretion at each farm during a whole year operation. The GHG emissions were estimated following Tier 2 guidelines rom IPCC. Differences in feeding strategies were analysed with a completely random block design using farms as a blocking factor. Results. Mean farm size was 5.0 ha for cut-and-carry and 16.0 ha for grazing, and dry matter feed self-sufficiency was 62 and 83% respectively, considering 12% and 22% refusals for each strategy. There were no statistically significant differences (P>0.05) for any of the N utilisation components (N in diet, N in milk, N in manure, NH3 and N2O or GHG emissions. Implications. This is a novel report on assessing N fluxes and GHG emissions from small-scale dairy systems in Mexico and Latin America. Conclusions. In general, 87.6% of the N consumed is excreted in manure and urine. The feeding strategies did not diverge enough to have an impact on GHG emissions.
This paper presents an intelligent system for the dynamic estimation of sheep body weight (BW). The methodology used to estimate body weight is based on measuring seven biometric parameters: height ...at withers, rump height, body length, body diagonal length, total body length, semicircumference of the abdomen, and semicircumference of the girth. A biometric parameter acquisition system was developed using a Kinect as a sensor. The results were contrasted with measurements obtained manually with a flexometer. The comparison gives an average root mean square error (RMSE) of 9.91 and a mean R2 of 0.81. Subsequently, the parameters were used as input in a back-propagation artificial neural network. Performance tests were performed with different combinations to make the best choice of architecture. In this way, an intelligent body weight estimation system was obtained from biometric parameters, with a 5.8% RMSE in the weight estimations for the best architecture. This approach represents an innovative, feasible, and economical alternative to contribute to decision-making in livestock production systems.
Background: The use of Tithonia diversifolia foliage can improve the quality of animal feed because its crude protein content doubles that of tropical grasses. However, plant response regarding ...biomass production to frequent harvest disturbances are not known well. Objective: To evaluate the effect of different cutting heights and repeated harvests on biomass production and nutrient content of T. diversifolia in fodder banks under warm sub-humid climate. Methodology: We used a completely randomized design with a factorial arrangement; the treatments consisted of six harvest dates: Mar, May, July, September, November 2019 and January 2020; and three harvest heights: 40, 60 and 80 cm from the ground level. After each harvest date, the biomass was separated into different components, weighed and dried. Samples were taken to analyse the chemical composition of the forage. Results: The highest yield of leaves was found in the month of January, while tender stems in November. The Senescent material and total biomass were lower in September. The cutting height influenced leaf yield. Crude protein content was higher in September at a cutting height of 60 cm. Neutral detergent fiber was higher in the month of November for all cutting heights. Likewise, the highest contents of acid detergent fiber were in November for all cutting heights and in January for the cutting height of 60 cm. Lignin content was similar for all treatments. Implications: These results contribute to the development sustainable livestock production by providing alternatives to reduce grassland degradation from overgrazing. Conclusion: Biomass yield and chemical composition of T. diversifolia are affected by harvest date and heights, so it is necessary to consider it in the management strategies for optimal use of forage resources, incorporation in silvopastoral systems and the development of sustainable livestock production.
Methane produced by enteric fermentation contributes to the emission of greenhouse gases (GHG) into the atmosphere. Methane is one of the GHG resulting from anthropogenic activities with the greater ...global warming contribution. Ruminant production systems contribute between 18% and 33% of methane emissions. Due to this, there has been growing interest in finding feed alternatives which may help to mitigate methane production in the rumen. The presence of a vast range of secondary metabolites in tropical trees (coumarins, phenols, tannins, and saponins, among others) may be a valuable alternative to manipulate rumen fermentation and partially defaunate the rumen, and thus reduce enteric methane production. Recent reports suggest that it is possible to decrease methane emissions in sheep by up to 27% by feeding them saponins from the tea leaves of Camellia sinensis; partial defaunation (54%) of the rumen has been achieved using saponins from Sapindus saponaria. The aim of this review was to collect, analyze, and interpret scientific information on the potential of tropical trees and their secondary metabolites to mitigate methane emissions from ruminants.
Deforestation of tropical forests for the establishment of grass monoculture for livestock production is responsible for about 30 % of COâ emissions. This issue is particularly severe in degraded ...pastures because degraded soils favor COâ flow to the soil surface. Silvopastoral systems could reduce COâ emissions, notably by using live fences. Here, we hypothesized that live fences of Gliricidia sepium in livestock systems should reduce variations in environmental relative humidity and soil temperature and, in turn, reduce soil COâ emissions. Here, we studied two livestock systems: (1) grass monoculture of Brachiaria decumbens with live fences of G. sepium and (2) grass monoculture of B. decumbens without live fences. We measured soil COâ seasonal emissions at different times of the day, soil temperature, and environmental relative humidity. Nine 600-m² plots were established in each system. All variables were measured over four 6-h period during a 24-h period, twice a month from April to September. Our results show that soil COâ emissions showed less variability with G. septum live fences than without live fences. This lower variability is explained by the creation of a microclimate with a higher and more stable environmental relative humidity, provided by the shade of trees. Results also show, however, that global soil COâ emissions did not differ between the two systems, with and without live fence. Moreover, soil COâ emissions varied according to season, as shown by 1.082 g COâ mâ»Â²Â hâ»Â¹ in the wet season versus 0.871 g COâ mâ»Â²Â hâ»Â¹ in the dry season. Soil COâ emissions varied also according to sampling time, as shown by 1.116 g CO â mâ»Â²Â hâ»Â¹ in the night versus 0.960 CO â mâ»Â²Â hâ»Â¹ in the morning.
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