ABSTRACT Desertification is the degradation process caused by climatic conditions and human activities that results in loss of soil productivity and decline in vegetation growth in the long term. Several indices related to vegetation, soil and climate are used to monitor desertification, but few studies explore qualitative and quantitative aspects of indices on desertification on spatial and hierarchical scale. This study aims to identify and measure indices related to increased risk of desertification on global, local and hierarchical scales using multinomial logistic regression models. Images from TM, ETM+ and OLI sensor from 1997 to 2018 in the end of dry and rainy seasons were used to quantify NDVI, TGSI, albedo, temperature, aridity index, evapotranspiration and precipitation on global spatial scale (Irauçuba Centro Norte) and local spatial scale (Miraíma, Canindé, Irauçuba and Santa Quitéria). GISD was calculated by geometric mean of weighted indices and segmented into 8 classes of susceptibility to desertification (hierarchical scale). The results showed that the best models were obtained on local scale and for the end of the rainy season. Temperature proved to be the most important variable for increased risk of desertification on global, local and hierarchical scales. Therefore, the increase in the risk of desertification in the studied areas is due to human activities of deforestation, overgrazing and fire. These factors contributed to reduction of vegetation cover and increase in temperature, changing the microclimatic, which led to decline in precipitation and worsening of desertification. term TM ETM 199 201 NDVI TGSI albedo temperature index Norte Miraíma, Miraíma (Miraíma Canindé Quitéria. Quitéria . Quitéria) scale) season Therefore deforestation fire microclimatic 19 20 1 2

ABSTRACT World demand for wood products and the shortage of good quality lumber species are exerting pressure on native forests. This study aimed to evaluate the efficiency of Eremanthus erythropappus crude oil in improving the resistance of Pinus taeda wood to Rhodonia (≈Postia) placenta, Gloeophyllum trabeum, Neolentinus lepideus (brown rot) and Pycnoporus sanguineus (white rot) in accelerated laboratory decay tests. Test samples measured 1.90 × 1.90 × 1.90 cm. Oil was applied to wood surfaces using a brush to obtain nominal retentions of 15, 30, 45, and 60 kg of oil per m3 of wood. After treatment, the samples reached average retentions of 16.25, 28.75, 41.50, and 53.75 kg m-3, respectively, and were submitted to a soil block decay test (accelerated decay test) for 12 weeks. Increased oil retention caused a decline in the mass loss of Pinus taeda wood exposed to the fungi tested. A retention of 16.25 kg m-3 inhibited Rhodonia placenta degradation and prevented other xylophagous fungi attacks. The most severe decay occurred with Rhodonia placenta and the least with Pycnoporus sanguineus. Oil improved Pinus taeda resistance to the decay fungi, indicating that it is useful for treating wood in contact with domestic animals and humans, since it is not toxic to them. forests ≈Postia Postia (≈Postia trabeum brown rot white tests 190 1 90 1.9 cm 15 30 45 6 m treatment 1625 16 25 2875 28 75 28.75 4150 41 50 41.50 5375 53 53.7 m3, 3, 3 respectively weeks tested 16.2 m- attacks humans them 19 9 1. 4 162 2 287 7 28.7 415 5 41.5 537 53. 16. 28. 41.

RESUMO A demanda mundial por produtos madeireiros e a escassez de espécies de madeira de boa qualidade estão pressionando as florestas nativas. Esta pesquisa teve como objetivo avaliar a eficiência do óleo de candeia (Eremanthus erythropappus) bruto para melhorar a resistência da madeira de Pinus taeda aos fungos apodrecedores Rhodonia (≈Postia) placenta, Gloeophyllum trabeum, Neolentinus lepideus (podridão parda) e Pycnoporus sanguineus (podridão branca) em ensaios de apodrecimento acelerado em laboratório. As amostras tinham dimensões nominais de 1,90 × 1,90 × 1,90 cm. O óleo foi aplicado nas superfícies da madeira com pincel, visando obter retenções nominais de 15; 30; 45 e 60 kg de óleo por m3 de madeira. As amostras após o tratamento atingiram retenções médias de 16,25; 28,75; 41,50; e 53,75 kg m-3, e foram submetidas ao teste solo-bloco (apodrecimento acelerado) durante 12 semanas. O aumento da retenção de óleo provocou redução na perda de massa da madeira de Pinus taeda submetida aos fungos testados. Observou-se que a retenção de 16,25 kg m-3 foi capaz de inibir a degradação do fungo Rhodonia (≈Postia) e prevenir o ataque de outros fungos xilófagos. Os maiores danos foram observados para Rhodonia (≈Postia) e os menores danos para Pycnoporus sanguineus. O óleo conferiu maior resistência à madeira de Pinus taeda aos fungos testados, indicando ser útil para o tratamento de madeiras que ficarão em contato com animais domésticos e seres humanos, uma vez que não é toxico a tais organismos. nativas Eremanthus erythropappus ≈Postia Postia (≈Postia placenta trabeum podridão parda branca laboratório 190 1 90 1,9 cm pincel 15 30 4 6 m 1625 16 25 28,75 2875 28 75 41,50 4150 41 50 5375 53 53,7 m3, 3, 3 solobloco solo bloco semanas testados Observouse Observou se 16,2 m- xilófagos humanos organismos 19 9 1, 162 2 28,7 287 7 41,5 415 5 537 53, 16, 28, 41,

ABSTRACT Unsustainable reclamation activities (URAs) have been increasingly conducted to respond to the rising global food demand, leading to severe repercussions on land environments. A total of 120 soil samples representing 12 sites were randomly selected in the three distinct land types (PMFs, PALs, and BHLs) to a depth of 60 cm. The impacts of URAs on soil properties and functions (SPFs) across the Nghe An mountainous province, Vietnam were assessed using the SPSS software (version 26.0) through a one-way analysis of variance (ANOVA). The findings indicated the distinct differences in soil particle size (SPS) among different land types (DLTs). Pristine and mixed forests (PMFs) exhibited the lowest sand ratios, ranging from 31.4 to 35.2%, while bare hills and lands (BHLs) recorded the highest sand ratios, ranging from 49.7 to 55.1%. High bulk density (BD) was observed in BHLs (1.36 ± 0.07 kg dm-3) and PMFs (0.89 ± 0.02 to 1.13 ± 0.03 kg dm-3) while perennial and annual lands (PALs) varied from 1.17 ± 0.04 to 1.25 ± 0.08 kg dm-3. PMFs showed low values for total soil porosity (TSP), and soil water content (SWC) with respective ranges of 32.97-36.18% and 4.72-6.15% while PALs and BHLs exhibited high values for TSP (39.25-43.19%; 43.97-49.62%), and SWC (7.39-10.07%; 9.98-12.74%). Cation exchange capacity (CEC), Ca2+, K+, and Mg2+ were recorded higher in PALs compared to PMFs and PALs while total organic contents (TOCs) detected little variation among DLTs. Overall, the URAs enhanced the adverse effects on the SPFs across the study area. (URAs demand environments 1 PMFs, (PMFs 6 cm (SPFs province version 26.0 260 26 0 oneway one way ANOVA. ANOVA . (ANOVA) SPS (SPS DLTs (DLTs) ratios 314 31 4 31. 352 35 2 35.2% (BHLs 497 49 7 49. 551 55 55.1% BD (BD 1.36 136 36 (1.3 007 07 0.0 dm3 dm 3 dm-3 0.89 089 89 (0.8 002 02 113 13 1.1 003 03 (PALs 117 17 004 04 125 25 1.2 008 08 dm3. 3. TSP, , (TSP) (SWC 32.9736.18% 32973618 32.97 36.18% 32 97 18 32.97-36.18 4.726.15% 472615 4.72 6.15% 72 15 4.72-6.15 39.2543.19% 39254319 39.25 43.19% 39 43 19 (39.25-43.19% 43.9749.62%, 43974962 43.97 49.62% 62 43.97-49.62%) 7.3910.07% 7391007 7.39 10.07% 10 (7.39-10.07% 9.9812.74%. 9981274 9.98 12.74% 9 98 74 9.98-12.74%) CEC, CEC (CEC) Ca2 Ca Ca2+ K K+ Mg2 Mg TOCs (TOCs Overall area 26. (ANOVA (DLTs 35.2 5 55.1 1.3 (1. 00 0. dm- 0.8 8 (0. 11 1. (TSP 9736 32.9736.18 3297361 3297 32.9 3618 36.18 32.97-36.1 726 4.726.15 47261 472 4.7 615 6.15 4.72-6.1 2543 39.2543.19 3925431 3925 39.2 4319 43.19 (39.25-43.19 9749 43.9749.62% 4397496 4397 43.9 4962 49.62 43.97-49.62% 3910 7.3910.07 739100 739 7.3 1007 10.07 (7.39-10.07 9812 9.9812.74% 998127 998 9.9 1274 12.74 9.98-12.74% (CEC 35. 55. (1 (0 973 32.9736.1 329736 329 32. 361 36.1 32.97-36. 4.726.1 4726 47 4. 61 6.1 4.72-6. 254 39.2543.1 392543 392 39. 431 43.1 (39.25-43.1 974 43.9749.62 439749 439 43. 496 49.6 43.97-49.62 391 7.3910.0 73910 73 7. 100 10.0 (7.39-10.0 981 9.9812.74 99812 99 9. 127 12.7 9.98-12.74 ( 32.9736. 32973 36. 32.97-36 4.726. 6. 4.72-6 39.2543. 39254 (39.25-43. 43.9749.6 43974 43.97-49.6 7.3910. 7391 10. (7.39-10. 9.9812.7 9981 12. 9.98-12.7 32.9736 32.97-3 4.726 4.72- 39.2543 (39.25-43 43.9749. 43.97-49. 7.3910 (7.39-10 9.9812. 9.98-12. 32.973 32.97- 39.254 (39.25-4 43.9749 43.97-49 7.391 (7.39-1 9.9812 9.98-12 (39.25- 43.974 43.97-4 (7.39- 9.981 9.98-1 (39.25 43.97- (7.39 9.98- (39.2 (7.3 (39. (7. (39 (7 (3

RESUMO As atividades de recuperação insustentáveis (URAs) têm sido cada vez mais realizadas para responder à crescente procura global de alimentos, levando a graves repercussões nos ambientes terrestres. Um total de 120 amostras de solo representando 12 locais foram selecionadas aleatoriamente nos três tipos distintos de terra (PMFs, PALs e BHLs) a uma profundidade de 60 cm para avaliar os impactos das URAs na província de Nghe An Mountain, no Vietnã. A análise estatística dos parâmetros do solo foi realizada no software SPSS (versão 26.0) por meio de análise de variância unidirecional (ANOVA). As descobertas indicam diferenças distintas no tamanho das partículas do solo (SPS) entre os diferentes tipos de terreno (DLTs). Florestas virgens e mistas (PMFs) exibiram as menores proporções de areia, variando de 31,4 a 35,2%, enquanto colinas e terras nuas (BHLs) registraram as maiores proporções de areia, variando de 49,7 a 55,1%. Elevado densidade global (BD) foi observado em BHLs (1,36 ± 0,07 kg dm-3) e PMFs (0,89 ± 0,02 a 1,13 ± 0,03 kg dm-3) enquanto terras perenes e anuais (PALs) variaram de 1,17 ± 0,04 a 1,25 ± 0,08 kg dm-3. Os PMFs apresentaram baixos valores de porosidade total do solo (TSP) e teor de água do solo (SWC) com respectivas faixas de 32,97-36,18% e 4,72-6,15% enquanto PALs e BHLs exibiram valores elevados para TSP (39,25-43,19%; 43,97-49,62%). e SWC (7,39-10,07%; 9,98-12,74%). A capacidade de troca catiônica (CEC), Ca2+, K+ e Mg2+ registrou altos valores nos PALs em comparação aos PMFs e PALs, enquanto o conteúdo orgânico total (TOCs) detectou pouca variação entre os DLTs. No geral, as URAs aumentaram os efeitos adversos nas propriedades e funções do solo (SPFs) em toda a área de estudo. (URAs alimentos terrestres 1 PMFs, (PMFs 6 Mountain Vietnã versão 26.0 260 26 0 ANOVA. ANOVA . (ANOVA) SPS (SPS DLTs (DLTs) areia 314 31 4 31, 352 35 2 35,2% (BHLs 497 49 7 49, 551 55 55,1% BD (BD 1,36 136 36 (1,3 007 07 0,0 dm3 dm 3 dm-3 0,89 089 89 (0,8 002 02 113 13 1,1 003 03 (PALs 117 17 004 04 125 25 1,2 008 08 dm3. 3. (TSP (SWC 32,9736,18% 32973618 32,97 36,18% 32 97 18 32,97-36,18 4,726,15% 472615 4,72 6,15% 72 15 4,72-6,15 39,2543,19% 39254319 39,25 43,19% 39 43 19 (39,25-43,19% 43,9749,62%. 43974962 43,97 49,62% 62 43,97-49,62%) 7,3910,07% 7391007 7,39 10,07% 10 (7,39-10,07% 9,9812,74%. 9981274 9,98 12,74% 9 98 74 9,98-12,74%) CEC, CEC , (CEC) Ca2 Ca Ca2+ K Mg2 Mg TOCs (TOCs geral SPFs (SPFs estudo 26. (ANOVA (DLTs 35,2 5 55,1 1,3 (1, 00 0, dm- 0,8 8 (0, 11 1, 9736 32,9736,18 3297361 3297 32,9 3618 36,18 32,97-36,1 726 4,726,15 47261 472 4,7 615 6,15 4,72-6,1 2543 39,2543,19 3925431 3925 39,2 4319 43,19 (39,25-43,19 9749 43,9749,62% 4397496 4397 43,9 4962 49,62 43,97-49,62% 3910 7,3910,07 739100 739 7,3 1007 10,07 (7,39-10,07 9812 9,9812,74% 998127 998 9,9 1274 12,74 9,98-12,74% (CEC 35, 55, (1 (0 973 32,9736,1 329736 329 32, 361 36,1 32,97-36, 4,726,1 4726 47 4, 61 6,1 4,72-6, 254 39,2543,1 392543 392 39, 431 43,1 (39,25-43,1 974 43,9749,62 439749 439 43, 496 49,6 43,97-49,62 391 7,3910,0 73910 73 7, 100 10,0 (7,39-10,0 981 9,9812,74 99812 99 9, 127 12,7 9,98-12,74 ( 32,9736, 32973 36, 32,97-36 4,726, 6, 4,72-6 39,2543, 39254 (39,25-43, 43,9749,6 43974 43,97-49,6 7,3910, 7391 10, (7,39-10, 9,9812,7 9981 12, 9,98-12,7 32,9736 32,97-3 4,726 4,72- 39,2543 (39,25-43 43,9749, 43,97-49, 7,3910 (7,39-10 9,9812, 9,98-12, 32,973 32,97- 39,254 (39,25-4 43,9749 43,97-49 7,391 (7,39-1 9,9812 9,98-12 (39,25- 43,974 43,97-4 (7,39- 9,981 9,98-1 (39,25 43,97- (7,39 9,98- (39,2 (7,3 (39, (7, (39 (7 (3

Summary: The state of Chiapas presents degradation processes of dif ferent kinds, as a consequence of the current established agricultural model. It is estimated that, in the near future, the surface of the state of Chiapas will present more than 55% degradation, generating changes in the physical, chemical and biological properties of the soil, af fecting the quality of life of human beings, mainly due to scarcity of food. The objective of this research was to evaluate the quality of the soils in three municipalities of the central depression of Chiapas, Mexico. The analysis were interpreted taking NOM-021-SEMARNAT-2000 as a reference and were classified according to the world reference base (WRB), version 2014. For the evaluation of soil quality, the sustainable use of land subindex (SUSS). 144 soil samples corresponding to 21 profiles were analyzed. Of the 21 profiles studied, 17 present poor soil qualities, two a sensitive quality, one acceptable quality and one with good quality. Only two soil groups presented good fertility and are classified as Vertisols and Phaeozems, which present good quality and capacity to maintain sustainable agricultural production in this region.

Resumen: El estado de Chiapas presenta procesos de degradación de diferente índole, como consecuencia del actual modelo agrícola establecido. Se estima que, en el futuro cercano, la superficie del estado de Chiapas presente más de 55% de degradación, generando modificaciones en las propiedades físicas, químicas y biológicas del suelo; afectando la calidad de vida de los seres humanos, principalmente por escasez de alimentos. El objetivo de esta investigación fue evaluar la calidad de los suelos en tres municipios de la depresión central de Chiapas, México. Los análisis se interpretaron tomando como referencia la NOM-021-SEMARNAT-2000 y se clasificaron de acuerdo con la world reference base (WRB), versión 2014, para la evaluación de calidad del suelo se utilizó el subíndice de uso sustentable del suelo (SUSS). Se analizaron 144 muestras de suelo correspondientes a 21 perfiles. De los 21 perfiles estudiados, 17 presentan calidad de suelo pobre, dos calidades sensibles, uno calidad aceptable y uno con calidad buena. Solo dos Grupos de suelo presentaron buena fertilidad y son clasificados como Vertisols y Phaeozems, los cuales presentan buena calidad y capacidad para mantener producción agrícola sostenible en esta región.

Resumen Introducción. La erosión acelerada del suelo es una de las principales causas de la degradación del suelo, que se ve reforzada por las actividades humanas que reducen la cobertura del suelo y aumentan su densidad. Metodologia: Por lo tanto, el objetivo de este estudio es cuantificar y comparar las pérdidas de suelo por erosión, entre áreas con agricultura convencional y vegetación natural en el sitio Potós ubicado en la zona rural del municipio de Ubajara, Ceará, Brasil. Resultados. Para monitorear la erosión, se instalan nueve pines de erosión en cada tratamiento, distribuidos en forma triangular, en el sentido de la pendiente, entre las hileras de plantas. El monitoreo se realizará mensualmente durante los años 2020 y 2021. Las pérdidas mensuales varían entre 0 y 948,73 Mg ha-1 mes, siendo las mayores en los meses más lluviosos, registrándose las mayores pérdidas en el año de mayor precipitación total acumulada.

Abstract Introduction. Accelerated soil erosion is one of the major causes of land degradation, which is exacerbated by human activities that reduce soil cover and increase its density. Objective. This study aimed to quantify and compare the levels of soil erosion between areas with conventional agriculture and natural vegetation at the Potós site located in the rural area of the municipality of Ubajara, Ceará, Brazil. Methodology. To monitor erosion, nine erosion pins were installed in each treatment area, arranged in a triangular mesh pattern, in the direction of the slope and between the rows of plants. Monitoring will occur monthly during 2020 and 2021. Results. Monthly losses range from 0 to 948.73 Mg ha-1 month, with the highest losses occurring in the driest months. The greatest losses were recorded in the year with the highest total accumulated precipitation.

Resumo Introdução: A erosão acelerada do solo é uma das principais causas de sua degradação, sendo esta potencializada por atividades antrópicas que reduzem a cobertura do solo e aumentam sua densidade. Objetivo: Ante isso, com o presente estudo objetivou-se quantificar e comparar as perdas de solos por erosão, entre áreas com agricultura convencional e vegetação natural no sítio Potós localizado na zona rural do município de Ubajara, Ceará, Brasil. Metodologia: Para monitorar a erosão foram instalados nove pinos de erosão em cada tratamento, distribuídos em malha triangular, no sentido do declive e entre as fileiras de plantas. O monitoramento ocorreu mensalmente durante os anos de 2020 e 2021. Resultados: As perdas de solos mensais variaram entre 0 e 948,73 Mg ha-1 por mês e foram maiores nos meses mais chuvosos, sendo as maiores perdas registradas no ano com maior precipitação total acumulada.

ABSTRACT Inadequate grassland management has resulted in the degradation of extensive areas, loss of productivity and sustainability of many of them, reflecting a common reality among livestock farmers in Colombia. Therefore, at the Paysandú Agricultural Station of the Universidad Nacional de Colombia, located in the Santa Elena township of the city of Medellín, a study was carried out to determine a soil quality index (SQI) by evaluating the physical and chemical indicators that were most related to the deterioration and dry matter production of kikuyu grass (Cenchrus clandestinus). A minimum data set (MDS) was established for the most sensitive indicators, selected by principal component analysis (PCA), and a nonlinear scoring function was used to obtain the SQI. Statistical differences were found between all the treatments in relation to dry matter production (P<0.05: 1.91x10-32). The most sensitive indicators were bulk density BD > total porosity TP > macropores MAC > micropores MIC > penetration resistance PR > effective cation exchange capacity ECEC > pH. As a result, the following formula was obtained: SQI = (0.225×BD) + (0.224×TP) + (0.220×MAC) + (0.218×MIC) + (0.113×PR) + (0.0879×ECEC) + (0.0877×pH). This index should be tested in kikuyu grass-dominated pastures located in the Colombian high tropics. The baseline is critical at values > 0.58 Mg m-3 for BD and > 2.25 MPa for PR. In addition, the optimum pH range for kikuyu grass development was between 5.4 and 6.4.

RESUMEN El manejo inadecuado de los pastizales ha provocado la degradación de extensas áreas, la pérdida de productividad y sostenibilidad de muchas de ellas, reflejando una realidad común entre los ganaderos de Colombia. Por ello, en la Estación Agraria Paysandú de la Universidad Nacional de Colombia, ubicada en el corregimiento de Santa Elena de la ciudad de Medellín, se realizó una investigación para determinar un índice de calidad del suelo (SQI) mediante la evaluación de los indicadores físicos y químicos más relacionados con el deterioro y producción de materia seca del pasto kikuyo (Cenchrus clandestinus). Se estableció un conjunto mínimo de datos (MDS) para los indicadores más sensibles, elegidos mediante el análisis de componentes principales PCA, y se utilizó una función de puntuación no lineal para obtener el SQI. Se encontraron diferencias estadísticas entre todos los tratamientos y la producción de materia seca (P<0,05: 1,91x10-32). Los indicadores más sensibles fueron: densidad aparente DR > porosidad total TP > macroporos MAC > microporos MIC > resistencia a la penetración PR > capacidad de intercambio catiónico efectiva ECEC > pH. Como resultado, se obtuvo el siguiente SQI = (0,225×BD) + (0,224×TP) + (0,220×MAC) + (0,218×MIC) + (0,113×PR) + (0,0879×ECEC) + (0,0877×pH). Se sugiere probar el índice en praderas dominadas por pasto kikuyo ubicadas en el trópico alto colombiano. La línea de base es crítica a valores > 0,58 Mg m-3 para BD y > 2,25 MPa para PR. Además, el intervalo de pH óptimo para el desarrollo del pasto kikuyo se situó entre 5,4 y 6,4.

ABSTRACT Soil salinization, a rising issue globally, is a negative effect of the ever-changing climate, which has drawn attention to, and exacerbated problems related to soil degradation and the decline in wetland rice (Oryza sativa L.) production, leading to an unstable national economy. The use of rhizosphere inhabiting microorganisms (plant growth-promoting rhizobacteria, PGPR) is a viable method for boosting agricultural production on saline soils and reduce salt stress in rice crops. The objective of this study was to support the development of rice under salt stress by using a consortium of bacterial strains. ‘Pokkali’ rice plants inoculated with single Bacillus tequilensis and B. aryabhattai isolates were compared with consortium and non-inoculated plants while salinity was increased and by irrigation with tap water (control), 30 mM (5 dS m-1) and 60 mM (10 dS m-1) NaCl. The present study exhibited that inoculation of a mixed inoculum at 5 dS m-1 resulted in significantly higher dry weight of the shoots and roots of seedlings (9.29 and 1.24 g, respectively) which was due to the increased SPAD value, proline content (7.55 µmol g-1 FW), and antioxidant enzyme activity in the inoculated plants. The higher accumulation of osmoprotectants such as proline supported Na+ ion reduction and antioxidant enzymes such as ascorbate peroxidase and reduced polyphenol oxidase content protect against higher cellular damage, eventually leading to increase plant growth performance in saline soil. This study demonstrates some positive effects of the locally isolated salt tolerant consortium PGPR strains on the growth of rice plants under salt stress conditions.

Abstract The forest soil provides various ecosystem services; however, it does not escape the phenomenon of degradation, a situation that has repercussions on the structure of the forests. This has been particularly noticeable in the La Malinche National Park, a natural protected area in Tlaxcala, Mexico, which has large areas with a variety of disturbance conditions. The objective of this study was to determine the physical and chemical properties of forest soils to obtain quality indicators by means of a Principal Component Analysis (PCA). Two sites were selected (San Francisco Tetlanohcan and Teolocholco), and five points exhibited different disturbance and vegetation in each site. The results show a higher percentage of sand in all soils (>70 %) than of clay and silt; bulk density >1 g cm-3, low organic matter content in all soils, and variability concerning nutrient content, except for phosphorus content, which was high at all sites, possibly depending on the type of vegetation and the condition at each of the sampling points. The Principal Component Analysis showed that bulk density, porosity, usable moisture, pH, cation exchange capacity, and concentrations of Mn, Na, Cu, B, Ca and K can be used to determine the physical and chemical quality of forest soils, which would support the design of rehabilitation strategies aimed at halting soil degradation within the protected natural area.

Resumen El suelo forestal proporciona diferentes servicios ecosistémicos, pero que no escapan del fenómeno de la degradación, situación que repercute en la estructura de los bosques. Esto ha sido particularmente notable en el Parque Nacional La Malinche, área natural protegida de Tlaxcala, México, la cual tiene grandes superficies con diferentes condiciones de perturbación. El objetivo del presente estudio fue determinar las propiedades físicas y químicas de suelos forestales para obtener indicadores de calidad por medio de un Análisis de Componentes Principales (ACP). Se seleccionaron dos sitios (San Francisco Tetlanohcan y Teolocholco) y en cada sitio se establecieron cinco puntos, con diferente condición de perturbación y vegetación. Los resultados muestran un mayor porcentaje de arena en todos los suelos (> 70 %) que de arcilla y limo; densidad aparente >1 g cm-3, contenido de materia orgánica bajo en todos los suelos y una variabilidad respecto a la parte nutrimental; a excepción del contenido de fósforo, que fue alto en todos los sitios, lo que posiblemente depende del tipo de vegetación y de la condición propia de cada uno de los puntos de muestreo. El Análisis de Componentes Principales evidenció que la densidad aparente, porosidad, humedad aprovechable, pH, capacidad de intercambio catiónico y las concentraciones de Mn, Na, Cu, B, Ca y K pueden emplearse para determinar la calidad física y química de los suelos forestales, lo cual apoyaría el diseño de estrategias de rehabilitación encaminadas a detener la degradación de los suelos dentro del área natural protegida.

ABSTRACT Among the problems of physical degradation of soils, compaction and densification are the main ones, and these cause strong decreases in subsequent crop yields. The degradation of the soil structure is a problem today in Cuba, which can occur in all soils and at all levels of livestock production. Taking into account the above, this document aims to expose the main changes produced in the internal structure of soils as a result of its degradation. Soil compaction, due to the collapse or reduction of pore spaces, is the most common cause of physical restriction for root growth and development. As an aggravating factor, the degradation of the soil structure is commonly considered the most difficult type of land degradation to locate and reconvert; the reason is that this degradation is a subsurface phenomenon. Finally, it is about establishing some possible solutions to this problem, among which the main method of restoring the porosity of the limiting layers of root growth and that must take into account the chemical and physical factors of the soil, the species, the type of soil and the degree of degradation of the species that are proposed to restore, the use of plowing v+ harrow or plowing alone is the most efficient method for the recovery of pastures of the species.

RESUMEN Entre los problemas de la degradación física de los suelos, la compactación y el adensamiento son los principales, y estos causan fuertes decrementos en los rendimientos posteriores de los cultivos de los mismos. La degradación de la estructura del suelo es un problema hoy en Cuba, que puede ocurrir en todos los suelos y a todos los niveles de producción pecuaria. Teniendo en cuenta lo anterior, este documento pretende exponer los principales cambios producidos en la estructura interna de los suelos como resultado de su degradación. La compactación del suelo, debido al colapso o disminución de los espacios de poros, es la causa más común de restricción física para el crecimiento y desarrollo de las raíces. Como agravante, la degradación de la estructura del suelo es comúnmente considerada como el tipo de degradación de tierras más difícil de localizar y reconvertir; la razón es que ésta degradación es un fenómeno subsuperficial. Finalmente se trata de establecer algunas posibles soluciones a dicha problemática, entre las cuales el método principal de restauración de la porosidad de las capas limitantes del crecimiento de las raíces y que se deben tener en cuenta los factores químicos y físicos del suelo, la especie, el tipo de suelo y el grado de degradación de las especies que se proponen restaurar, el uso de la aradura + grada o de la aradura sola resulta el método más eficiente para la recuperación de pastizales de las especies

ABSTRACT The conventional intensive agriculture, resultant of the technological and social development is the biggest degrader of waters and agricultural environments. The agricultural mechanization and the irrigation in general are the main causing factors of the degradation, for what should always be used with conservationist and recuperative technologies. Diverse projects and programs of international collaboration related with the protection of the environment have been carried out, among whose objectives are the research of the effects of the agricultural mechanization on the environment, reason why was taking as objective to center the efforts in carrying out a study to determine the possible measures to counteract the negative aspects of this influence, like basis for the elaboration of new research projects of international collaboration. For the study were used the methodologies for the realization of the Participative Diagnostics, which included the realization of surveys, discussion seminars and statistical analysis, with the use of computing tools and programs. Among the main conclusions of the study is the description of the possible measures guided to reduce the impacts of the agricultural mechanization on the environment.

RESUMEN La agricultura intensiva convencional, resultante del desarrollo tecnológico y social es el mayor degradador de aguas y ambientes agrícolas. La mecanización agrícola en general y el riego son los principales factores causantes de la degradación, por lo que debe utilizarse siempre con un sentido conservacionista y recuperador. Se han estado desarrollando diversos proyectos y programas de colaboración internacional relacionados con la protección medioambiental, entre cuyos objetivos se encuentra la investigación de los efectos de la mecanización agropecuaria sobre el medio ambiente, por lo cual ser trazó como objetivo centrar los esfuerzos en realizar un estudio para determinar las posibles medidas para contrarrestar los aspectos negativos de esta influencia, como base para la fundamentación de nuevos proyectos de investigación y de colaboración internacional. Se emplearon las metodologías para la realización de los Diag nósticos Participativos, la cual comprendió la realización de encuestas, seminarios de discusión, análisis estadístico, con el uso de herramientas y programas de computación. Entre las principales conclusiones del estudio se encuentra la descripción de las posibles medidas encaminadas a reducir los impactos de la mecanización agropecuaria sobre el medio ambiente.

ABSTRACT Pesticides, such as insecticides, fungicides, herbicides, and rodenticides, are a group of chemical compounds that have different actions. After their application, the degradation process is slow. They can remain in the soil and groundwater, contaminating the water. Climate change transforms the process of degradation of chemical compounds, by altering soil composition, producing alterations in the ecosystem and biodiversity. The impact of pesticides on human health is challenging because of the great potential for harm they have. Since 2004, genetically modified seeds have been introduced in Paraguay, accompanied by a great increase in cultivation areas and pesticide use. To review the current state of knowledge about the effects of these chemical substances on the different organs and systems in pediatric and pregnant populations, a descriptive review was carried out, utilizing the main available databases. As a secondary objective, considering the extension of cultivation areas in Paraguay, we also described the results of studies carried out in the country. The results of the reviewed studies show an association between the involvement of different organ systems in these populations and environmental exposure, water, and food. Some of these results are replicated in those carried out in the country's growing areas.

RESUMEN Los pesticidas son un grupo de compuestos químicos que tienen diferentes acciones, insecticidas, fungicidas, herbicidas, rodenticidas. Luego de su aplicación el proceso de degradacion es lento. Pueden permanecer en el suelo y en las aguas subterráneas, contaminando el agua. El cambio climático transforma el proceso de degradación de los compuestos químicos, por la alteración de la composición del suelo, produciendo alteraciones en el ecosistema y la biodiversidad.El impacto de los pesticidas sobre la salud humana es un desafío por el gran potencial de daño que tienen. Desde el año 2004, se introduce en Paraguay las semillas geneticamente modificadas, acompañado de un gran incremento de las areas de cultivo y la utilizacion de pesticidas.Con el objetivo de revisar el estado del conocimiento actual sobre los efectos de estas sustancias quimicas, sobre los diferentes organos y sistemas en las poblaciones pediatricas y embarazadas, se realizo una revision descriptiva, abarcando las principales base de datos disponibles.Como objetivo secundario, considerando la extension de areas de cultivo en Paraguay, describir los resutlados de los estudios realizados en el pais. Los resultados de los estudios revisados muestran asociacion entre afectacion de diferentes organos, sistemas, de estas poblaciones y la exposcion ambiental, de las aguas y los alimentos. Algunos de estos resultados se replican en los realizados en las zonas de cultivo del pais.

Abstract The natural durability of wood is defined as its intrinsic ability to resist degradation caused by biotic and abiotic factors. There are few records of natural wood durability in Mexico; in this study, it was determined based on the degradation of the wood of six commercial species: Pinus durangensis, P. strobiformis, P. cooperi, Juniperus deppeana, Quercus sideroxyla, and Alnus acuminata, in addition to Fagus sylvatica as the control. Test specimens were placed in contact with soil for 12 months at the Mineral de Nuestra Señora de la Candelaria Ecological Reserve of in Cósala, Sinaloa, and at the Las Bayas property in the state of Durango. Five specimens of each species were buried at 50 % of their length and analyzed following the UNE-EN 252:2015 European standard for determining degradation in wood, and UNE-EN 350:2016 for estimating durability. Due to the absence of normality (p<0.05) in the degradation data, the Kruskall-Wallis nonparametric test was used to determine statistical differences between species, locality, and puncture area. Statistical analysis was performed in the R-Studio program. According to UNE-EN 252:2015 and UNE-EN 350:2016, J. deppeana was the most durable wood classified as Class 1; Q. sideroxyla, P. strobiformis, P. durangensis and F. sylvatica (control) were Class 2 timbers, with slight damage; and A. acuminata and P. cooperi were classified as Class 3, with evident degradation. It is concluded that J. deppeana has the most durable wood.

Resumen La durabilidad natural de la madera se define como la capacidad intrínseca que tiene para resistir la degradación ocasionada por factores bióticos y abióticos. Existen pocos registros de la durabilidad natural de la madera en México; en este estudio se determinó con base en la degradación de la madera de seis especies comerciales: Pinus durangensis, P. strobiformis, P. cooperi, Juniperus deppeana, Quercus sideroxyla y Alnus acuminata, además de Fagus sylvatica como testigo. Se usaron probetas colocadas en contacto con el suelo por 12 meses en dos localidades: la Reserva Ecológica del Mineral de Nuestra Señora de la Candelaria en Cósala, Sinaloa, y el predio Las Bayas, Durango. Cinco probetas de cada especie se enterraron a 50 % de su longitud y se analizaron siguiendo la norma europea UNE-EN 252:2015 que determina la degradación en la madera, y la UNE-EN 350:2016 para la durabilidad. Debido a la ausencia de normalidad (p<0.05) en los datos de degradación, se usó la prueba no paramétrica de Kruskall-Wallis para determinar diferencias estadísticas entre especies, localidad y área de punzado. El análisis estadístico se realizó en el programa R-Studio. De acuerdo con las normas UNE-EN 252:2015 y UNE-EN 350:2016, J. deppeana fue la madera más durable clasificada como Clase 1; Q. sideroxyla, P. strobiformis, P. durangensis y F. sylvatica (control), fueron maderas Clase 2, con ligero daño; A. acuminata y P. cooperi clasificaron como Clase 3, con evidente degradación. Se concluye que J. deppeana presenta la madera más durable.

Abstract Mountain areas face various problems such as environmental degradation, deforestation, unsustainable agricultural expansion, soil erosion, coupled with the loss of traditional knowledge, among others, which has become the focus of concern and reflection of both theoretical and practical discourse, due to the environmental, economic and social deterioration they have experienced. Higher Education in Cuba plays a very important role in the face of these problems, by contributing, through scientific means, to their solution. The following original research has as its objective to implement agroforestry resilience actions in mountainous areas from community projects with the Municipal University Center of Remedios in the province of Villa Clara, Cuba. The methodology used was participatory action research, using theoretical methods such as synthetic analytical and historical-logical, empirical methods such as document analysis, observation, interviews, which allowed recording the information directly from the subjects studied and workshops with brainstorming techniques in the dynamics of the research. The results have been structured in the foundation of the conceptual elements necessary to clarify the object of study, main needs and potentialities of the mountainous area studied, as well as agroforestry resilience actions, which allowed greater public participation in the community context in the management of its natural resources, aimed at contributing to the fulfillment of the Sustainable Development Goals (Agenda 2030) and one of the strategic axes within the National Economic and Social Development Plan of Cuba.

Resumo As áreas montanhosas enfrentam vários problemas, como a degradação ambiental, o desmatamento, a expansão agrícola insustentável, a erosão do solo, juntamente com a perda de conhecimentos tradicionais, entre outros, razão pela qual se tornaram foco de preocupação e reflexão tanto no discurso teórico quanto no prático, devido à deterioração ambiental, econômica e social que sofreram. A educação superior em Cuba desempenha um papel muito importante no enfrentamento desses problemas, contribuindo para sua solução por meios científicos. A pesquisa original a seguir tem como objetivo implementar ações de resiliência agroflorestal em áreas montanhosas por meio de projetos comunitários com o Centro Universitário Municipal de Remedios, na província de Villa Clara, Cuba. A metodologia utilizada foi a pesquisa-ação participativa, com o uso de métodos teóricos, como os métodos analítico sintético e histórico-lógico, métodos empíricos, como análise de documentos, observação e entrevistas, que possibilitaram o registro de informações diretamente dos sujeitos investigados, e oficinas com técnicas de brainstorming na dinâmica da pesquisa. Os resultados foram estruturados na fundamentação dos elementos conceituais necessários para esclarecer o objeto de estudo, principais necessidades e potencialidades da área montanhosa estudada, bem como ações de resiliência agroflorestal, que permitiram maior participação pública no contexto comunitário na gestão de seus recursos naturais, visando contribuir para o cumprimento dos Objetivos de Desenvolvimento Sustentável (Agenda 2030) e um dos eixos estratégicos dentro do Plano Nacional de Desenvolvimento Econômico e Social de Cuba.

Resumen Las zonas montañosas enfrentan diversas problemáticas como la degradación ambiental, la desforestación, la expansión agrícola no sostenible, la erosión del suelo, unido a la pérdida de conocimientos tradicionales, entre otros, por lo que se ha convertido en centro de preocupación y reflexión tanto del discurso teórico como práctico, debido a su deterioro ambiental, económico y social que han experimentado. La Educación Superior en Cuba juega un papel muy importante ante estas problemáticas, al contribuir con la vía científica, a su solución. La siguiente investigación original tiene como objetivo implementar acciones de resiliencia agroforestal en zonas montañosas desde proyectos comunitarios con el Centro Universitario Municipal de Remedios en la provincia de Villa Clara, Cuba. La metodología utilizada fue la investigación acción participación, se emplearon métodos teóricos como el analítico sintético y el histórico lógico, empíricos como el análisis de documentos, la observación, entrevistas, que permitieron registrar la información directamente de los sujetos investigados y los talleres con técnicas de lluvia de ideas en la dinámica de la investigación. Los resultados han quedado estructurados en la fundamentación de los elementos conceptuales necesarios para esclarecer el objeto de estudio, principales necesidades y potencialidades de la zona montañosa estudiada, así como acciones de resiliencia agroforestal, que permitieron una mayor participación pública en el contexto comunitario en la gestión de sus recursos naturales, orientado a contribuir al cumplimiento de los Objetivos del Desarrollo Sostenible (Agenda 2030) y uno de los ejes estratégicos dentro del Plan Nacional de Desarrollo Económico y Social de Cuba.

There is growing evidence that soil degradation, among other factors, has led to both the decline and constraint of agriculture in southern Africa. Conservation and regenerative agriculture (CA/RA) have been proposed as a grain crop production system that could slow down, halt or even reverse some of these disturbing trends. But the question remains whether it is financially viable. We sought to find an answer to this question by comparing the financial returns of a CA/RA system over a 20-year period to its alternatives, namely conventional tillage (CT) and no-tillage (NT) production systems. The cumulative free cash flow (CFCF) of the average between the realistic and conservative CA/RA scenarios in year 20 is considerably higher than that of the other systems under investigation. The CFCF for CA/RA in year 20 in Mpumalanga is estimated to be ZAR86 million, compared to -ZAR51 million for CT and about ZAR4 million for NT. That is a net difference between ZAR137 million (compared to CT) and ZAR82 million (compared to NT). In the Maluti area, the CFCF for the CA/RA production system is estimated at ZAR26 million, compared to -ZAR66 million for CT and -ZAR19 million for NT. In the North-West production area, the CFCF for the CA/RA production system is estimated at ZAR35 million, compared to -ZAR9 million for CT and about ZAR21 million for NT. The differences between the CFCF of the CA/RA system and the other systems represent the financial opportunity cost of not converting to the CA/RA system. SIGNIFICANCE: • Soil degradation leads to both the decline and constraint of agriculture in southern Africa. • Conservation and regenerative agriculture (CA/RA) have been proposed as a grain crop production system that could slow down, halt or even reverse some of these disturbing trends. • CA/RA are financially more viable in three grain production areas of South Africa. • The cumulative free cash flow (CFCF) CA/RA in year 20 is considerably higher than that of the other systems. • The differences between the CFCF of the CA/RA system and the other systems represent the financial opportunity cost of not converting to the CA/RA system.

ABSTRACT The agricultural frontier in the Semiarid Pampas Region of Argentina has expanded into marginal environments, resulting in the current reactivation of wind erosion hotspots and desertification processes. Zoning based on soil quality indicators (SQI) reveals differences in soil degradation. The aim of this study was to define zones based on the susceptibility of sandy soils to wind erosion in a 1,4 million hectare plain in the Pampa Medanosa at the south of Cordoba province, Argentina. Soil quality indicators related to wind erosion (erodible fraction (FE), organic carbon (CO) and clay and silt contents, and dry structural stability) were analyzed in samples from 0-5 cm depth at 283 sites. Spatial principal component analysis (PCA) and cluster analysis were performed to group sites with similar characteristics and define subregions based on erosion susceptibility. Four subregions (SR) with different susceptibility were identified: SR-I, with the highest potential wind erosion rate (EEP) (65 t. ha-1. year-1), the lowest CO values (10.95 g.kg-1), and the highest FE, 41%, which is above the permissible threshold (40%); SR-II, the largest in extension, with an EEP of 51 t. ha-1. year-1, showed a FE of 36% and 12.47 g.kg-1 of CO; SR-III, with an EEP of 35 t. ha-1. year-1, 31% FE, and 13 g.kg-1 of CO; SR-VI, with an EEP of 20 t. ha-1. year-1, 30% more CO than SR-I, 14.26 g.kg-1, and a FE of 27%. The results have allowed understanding that the Pampa Medanosa is a heterogeneous region where it is necessary to implement wind erosion mitigation techniques and respect the soil’s potential use in each subregion to achieve sustainable agricultural production systems.

RESUMEN La frontera agrícola en la Región Pampeana Semiárida Argentina ha avanzado sobre ambientes marginales observándose como consecuencia la reactivación de focos de erosión eólica y de procesos de desertificación. La zonificación a través del estudio de indicadores de la calidad de suelo refleja diferencias en cuanto a la degradación. El objetivo del presente trabajo fue definir zonas por susceptibilidad a la erosión eólica en la Pampa Medanosa. Esta es una planicie arenosa ubicada al sur de Córdoba con 1,4 MM de hectáreas. Se analizaron indicadores de calidad del suelo (ICS) relacionados con la erosión eólica (fracción erosionable (FE), carbono orgánico (CO), arcilla más limo y estabilidad estructural en seco) en muestras de 0-5 cm de profundidad de 283 sitios. Se realizó un análisis de componentes principales espaciales (ACPe) y un análisis de clústeres para agrupar sitios con características similares y definir subregiones por susceptibilidad a la erosión. Se identificaron cuatro subregiones (SR) con distinta susceptibilidad: la SR-I de mayor tasa de erosión eólica potencial (EEP), 65 t. ha-1. año-1, con los menores valores de CO (10,95 g.kg-1) y la mayor FE, 41%, sobre umbral admisible (40%). La SR-II de mayor extensión, con una EEP de 51 t. ha-1. año-1 presentó una FE de 36% y 12,47 g.kg-1 de CO. La SR-III, con una EEP de 35 t. ha-1. año-1, 31% de FE y 13 g.kg-1 de CO. Y la SR- VI, con una EEP de 20 t. ha-1. año-1 y un 30% más de CO que la SR-I, 14,26 g.kg-1, con una FE de 27%. Los resultados han permitido comprender que la Pampa Medanosa es una región heterogénea en la que para alcanzar sistemas de producción agropecuarios sustentables es necesario implementar técnicas de mitigación de la erosión eólica y respetar el potencial de uso de los suelos de cada subregión.