Los gradientes altitudinales pueden generar límites ambientales, influyendo en el crecimiento y desarrollo de las especies vegetales. Se tuvo por objetivo identificar las variaciones edafoclimáticas en gradientes altitudinales y su influencia en los bosques tropicales. Se buscaron artículos de investigación con ámbito geográfico entre 27º N y 27º S de latitud, con influencia de gradientes altitudinales entre 0 m y 5000 m. Se sistematizó la información, organizándose en temáticas del clima, en las propiedades fisicoquímicas y biológicas del suelo, y en el comportamiento de las especies forestales. Se determinó que la temperatura media anual (TMA) disminuye conforme aumenta la altitud; y la precipitación anual (PA) presenta máximos pluviales en altitudes medias. Los valores del pH del suelo disminuyen hasta 3000 m, aumentando sobre esta altitud; sin embargo, la materia orgánica, carbono orgánico, carbono total (CT), nitrógeno total (NT) y la relación C/N del suelo aumentan hasta 3000 m; sobre esta altitud los valores disminuyen. El potasio (K), el calcio (Ca), el magnesio (Mg), el fierro (Fe), y el aluminio (Al) del suelo disminuyen con el aumento de la altitud por influencia de las bajas temperaturas y humedad del suelo (HS). La variación edafoclimática en los gradientes altitudinales interactúa con las especies forestales, afectando las respuestas fisiológicas, disminuyendo su crecimiento y altura con el aumento de la altitud; del mismo modo disminuye su densidad y diversidad con el aumento de la altitud. Las especies forestales de los trópicos prosperan en amplios o estrechos límites altitudinales y edafoclimáticos, por lo que identificar estos límites es fundamental no solo en términos ecológicos, sino también políticos y económicos, para diseñar políticas efectivas de uso de la tierra y de conservación.

Tara production occurs mainly in the altitude gradient, where the edaphoclimatic conditions that affect the production of pods still need to be understood. The goal was to determine the altitudinal and edaphoclimatic effect on the production of tara pods in agroforestry and natural remnants in Cajamarca, Peru. Data analyses performed were the following: principal component analysis (PCA), regression analysis, the bootstrap method, and Pearson correlation analysis. For each 1 °C increase in temperature, the length and width of the pod decreased by 2.1 and 0.62 mm, and of the seed by 0.17 and 0.12 mm in the agroforestry environment; likewise, pod, valve, seed and gum weights were reduced by 23.9, 10.9, 13 and 2.3 g in the agroforestry environment, and 22.3, 13, 9.3 and 2.1 g in the natural environment. Activities such as association with annual crops and perennial pasture possibly favor the length and width of the pod and seed and the weight of the pod, valve, seed and gum in the agroforestry environment when compared to the natural environment. Larger pod and seed dimensions and higher pod, valve, seed and gum weights are related to higher soil CaCO₃ contents in the natural environment and higher soil P and B contents in the agroforestry environment at higher altitudes. Higher Fe contents in the soil suggest an improvement in tara’s tannin weight (valve) in the natural and agroforestry environment. The effective response of tara, reflected in its weight and size of pods, was higher in an agroforestry environment than in a natural environment. Further studies on the production of tara pods are necessary for a better understanding of the interaction between altitude and soil fertility to expand the revenue and employment of Peruvian tara farmers.

This research examined how edaphoclimatic variations are related to dendrometric variables of the Tara tree in natural and agroforestry systems in Cajamarca, Peru. Evaluations followed three approaches: (a) principal components analysis (PCA) with environmental factors and altitude classes with 1 °C of temperature variation for edaphic and dendrometric variables; (b) evaluation of possible differences by the bootstrap method for the different variables in the PCAs; and (c) correlation analysis between plant density, plant and crown height, stem and crown diameter, and the number of stem branches with the physical and chemical attributes of the soil and with air temperature. In the altitudinal gradient from 2021 to 3007 ± 7 m, the temperature ranged from 19.8 to 13.4 ± 0.4 °C; the soils possessed alkaline pH, high organic matter (OM), K and CEC, lower contents of CaCO₃, N, P, K, B, Cu, Fe, Mn, and Zn. The soil properties with the most significant contribution to PCAs were OM, CEC, N content, and sand, with no variation among environments but among altitudes. None of the dendrometric variables varied as a function of altitude and temperature in PCAs run in the natural environment. However, in the agroforestry environment, there was a greater crown diameter, and tree and crown height in the 2185 m altitude class associated with Medicago sativa. In contrast, the opposite behavior was found in these variables and in the altitude class 2798 m associated with low Fe content, and already in the altitude class at 3007 m, a larger stem diameter is associated with higher levels of CaCO₃. The anthropic effect on the agroforestry environment did not significantly alter the soil’s CEC, OM, N, and sand. Tara’s crown diameter and tree height appeared higher in agroforestry environments. The variations of Fe and CaCO₃ in the soil might have influence on the development of Tara individuals in natural and agroforestry environments. It is important to carry out further studies for a better understanding of the relationship between the production of Tara pods and soil fertility in altitudinal variation, aiming to improve the income and employment of family farmers who exploit Tara in the Peruvian Andes.

Faced with the challenges of extreme climatic events and increasing food demand, cowpea farming offers a viable option for generating grains and foliage while aiding soil preservation. This research aimed to evaluate the impact of diverse organic fertilizers and plastic mulches on cowpea yields and soil macrofauna. A completely randomized block design was employed, with a factorial arrangement of 3 × 3 + 1, encompassing plastic mulch (3.5 mm) color (white, black, and blue), organic fertilizer (compost of chicken manure-agricultural soil-dolomite, island guano, and cattle manure compost), as well as a control (without synthetic mulch and organic fertilization). The study evaluated soil temperature, plant height, area biomass, foliar macronutrients, yield, and soil macrofauna. The findings demonstrate that soil temperature varies based on the color of the plastic mulch. It was observed that using organic fertilizers resulted in significantly taller plants than the control group, with fresh and dry biomass weight also being significantly greater (p<0.05) for cattle manure compost compared to the other treatments. Furthermore, the use of plastic mulches had an impact on soil macrofauna. Cowpea displayed resistance to low soil fertility and fluctuations in soil temperature ranging from 40°C. However, high precipitation during the fruiting and harvesting seasons significantly impacted grain yields. Organic fertilizers produced noticeable variances (p<0.05) in the aerial biomass weight of cowpeas, particularly cattle manure compost. The data, indicates that soil macrofauna, like the earthworm Pontoscolex corethrurus, improved the availability of N, P, and K to the plant during the reproductive stage. Plastic mulches and organic fertilizers were linked to an increase in earthworm weights, specifically P. corethrurus. Additionally, plastic mulches served as a physical barrier against ants and bugs.

Camu-camu is a native plant of the Peruvian Amazon. It is noted for its high concentration of ascorbic acid, however this feature varies widely from one location to another due to genetic and environmental factors. In order to determine the relationship between mineral nutrients and the concentration of ascorbic acid in camu-camu plants, a study was conducted in three camu-camu producing areas in flood-prone soils and soils on dry land conditions in the Ucayali Region. For this purpose, soil samples and camu-camu were collected. The content of following macronutrients was analyzed: nitrogen, phosphorus, potassium, calcium and magnesium; also was determined the concentration of aluminum, pH, organic matter and ascorbic acid. The results show that the camu-camu plantations located in upland soils had lower concentrations of ascorbic acid and lower natural fertility, than soils prone to flooding. Ascorbic acid is negatively related to the concentration of aluminum and positively to the concentration of magnesium and phosphorus in the camu-camu producing areas. It is concluded that the concentration of ascorbic acid in camu-camu plants is best expressed when soils have better chemical attributes and good conditions of natural fertility.

In the Peruvian tropics, crossbreeding occurs between Bos taurus cattle, such as Brown Swiss (BS), Holstein (H), and Jersey (J), and Bos indicus cattle, such as Brahman (B) and Gyr (G). However, these cattle are exposed to high temperature humidity indices (THI). The aim was to evaluate variations in milk components, blood parameters of cows, and weight gain of calves in pasture-based production systems with mixed approaches along an altitudinal gradient. Six cows and six calves were evaluated at altitudes of 170, 503, 661, and 1110 m. Cattle experience higher heat stress in monoculture pasture areas; however, silvopastoral areas and altitudinal gradients mitigate this stress. The fat content in the milk of BSxJ cows showed significant differences (CI: 95%), with lower values; glucose and hemoglobin in their blood exhibited strong positive and negative correlations (p<0.05) with THI. At 661 m, the milk from GxH cows had higher values of fat, solids, density, protein, and salts, which were associated with better chemical properties of the pastures. Blood electrolytes Cl ^- and Na ⁺ tended to be higher in BSxG cows, while Na ⁺ levels were lower in GxH cows. However, red blood cells and hemoglobin were higher in GxH cows and lower in cows crossed with BS. In calves, the highest weight gains at lower altitudes were observed in BSxB crosses, while at higher altitudes, GxH crosses showed the greatest gains, likely associated with better production management.