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A expansão da agropecuária juntamente com o processo de urbanização são fatores que podem contribuir para a redução de florestas nativas em diversas regiões do Brasil. Assim, o objetivo deste trabalho foi analisar o grau de alteração antrópica da paisagem no município de Santa Fé do Araguaia/Tocantins, no período de 2009 a 2019. Para tanto, realizou-se levantamento bibliográfico em bases oficiais de consulta: SciELO e Portal de Periódico Capes sobre as alterações na paisagem, além da obtenção de forma gratuita das bases cartográficas do Instituto Nacional de Pesquisas Espaciais, na escala de 1:100.000, por meio do seu website. Essas bases foram recortadas, delimitando a área de estudo, utilizando os softwares livres QGis, versão 3.18 e Spring versão 5.4.3. Os dados analisados mostram uma redução da vegetação causada, principalmente, pela pecuária extensiva, que atualmente ocupa 75,65% do município estudado. Os tipos de vegetação Savana Florestada e a Área de Tensão Ecológica, com contato entre Savana e Floresta Ombrófila, tiveram suas áreas reduzidas a 0%, enquanto a Floresta Ombrófila Aberta Submontana teve uma redução de 12,14%. Diante dos resultados, é notável destacar a preocupação com o avanço do desflorestamento, uma vez que as florestas fornecem importantes funções para o equilíbrio dos ecossistemas.

Noboa is a rural parish of the canton 24 Mayo, Manabí province, in this context the present investigation is carried out in order to know the amount of tree cover loss and the main causes that cause it. The methods used were descriptive, deductive and theoretical, in addition, an NDVI map was made with Landsat 8 satellite images from the year 2013 through Earth Explorer and with the QGIS desktop 3.16.1 program, the procedure to obtain data was carried out as well Also the use of the global forest watch tool that shows the amount of tree cover loss in any plot greater than 5 meters in which the loss of 435 ha of tree cover was obtained from the years 2008 - 2018 in the parish, representing a decrease of 3.6% since 2000. The main human activities of the parish are itinerant agriculture and forestry with 12288 ha, cattle ranching with 3776 ha and villages and roads with an extension of 538 ha with an area of 16602 ha that represents the area, the same ones that cause tree loss and mostly cause forest fires by using land in these activities. [ABSTRACT FROM AUTHOR]

Remote sensing is an essential tool for monitoring and mapping vegetation. Multitemporal analysis of satellite imagery allows for the observation of landscape evolution, fostering the development of management plans aimed at preserving natural resources and maintaining biodiversity. The objective of this article was to present a multitemporal analysis of land use and land cover in the municipality of São José dos Campos, SP, with a focus on vegetation cover, using TM-Landsat 5 and OLI-Landsat 8 images, over a period of 10 years (2010 to 2020). These images were classified into the following classes: Cerrado (savanna), Atlantic Forest, anthropogenic areas, reforestation, agricultural areas, water bodies, and urban areas, using supervised classification techniques in ArcGIS software. The results showed an increase of 4.52% in the urban area, an increase of 314.17% in the silviculture areas and consequently the reduction of the original vegetation cover of the municipality, where the areas of Cerrado were reduced by 88.9% and those of Atlantic Forest by 8.57%, evidencing the need for the implementation of projects and public policies that favor the preservation of the natural plant remnants of São José dos Campos and the protection of endemic species belonging to the present biomes in the region. [ABSTRACT FROM AUTHOR]

O Sensoriamento Remoto é uma ferramenta imprescindível para o monitoramento e mapeamento da vegetação. As análises multitemporais de imagens obtidas por satélites propiciam a observação da evolução da paisagem, fomentando a elaboração de planos de manejo que visam a preservação dos recursos naturais e a manutenção da biodiversidade. Este artigo teve como objetivo apresentar uma análise multitemporal do uso e cobertura da terra do município de São José dos Campos, SP, com ênfase na cobertura vegetal, utilizando imagens do TM-Landsat 5 e OLI-Landsat 8, no período de 10 anos (2010 a 2020). Estas imagens foram classificadas nas classes Cerrado, Mata Atlântica, campo antrópico, reflorestamento, área agrícola, corpos d’água e área urbana, utilizando técnicas de classificação supervisionada, a partir do Software ArcGis. Observaram-se aumento em 4,5-% e 314-%, da área urbana e de silvicultura, respectivamente, e consequentemente a redução da cobertura vegetal original do município. As áreas de Cerrado foram reduzidas em 89% e as de Mata Atlântica em 8,6%. Estes resultados evidenciam a necessidade da implantação de projetos e políticas públicas que favoreçam a preservação dos remanescentes vegetais naturais de São José dos Campos e proteção das espécies endêmicas pertencentes aos biomas presentes na região

La fracción de cobertura vegetal (FCV) y el índice de área foliar (IAF) son variables biofísicas relacionadas estrechamente con la tasa de evapotranspiración de los cultivos y su producción de biomasa. A pesar de su importancia, usualmente no se miden de manera directa debido al tiempo invertido y costo; sin embargo, se pueden estimar a gran escala y en tiempo casi real mediante información espectral captada en imágenes de satélite, pero esto requiere de su validación a nivel de campo. Se desarrollaron y validaron modelos de regresión lineal simple utilizando 13 índices de vegetación (IV) relacionados con el IAF y la FCV en alfalfa (Medicago sativa). Se usaron tres fuentes de información espectral: (i) La reflectancia para derivar los IV; (ii) fotografías digitales procesadas con Canopeo para estimar la FCV; y (iii) mediciones del IAF utilizando un ceptómetro. Se realizaron seis muestreos de campo entre marzo y junio de 2020, en cuatro parcelas de alfalfa situadas en Palmar de Bravo, Puebla, México. Para evaluar cada IV, se utilizó el coeficiente de determinación (R2) y la raíz del cuadrado medio del error (RCME). Se encontró que el IV más apropiado para estimar la FCV fue el VIgreen (Green Vegetation Index, R2 = 0.987 y RCME = 0.093). En el caso del IAF, el IV que presentó el mejor desempeño fue el Normalized Difference Vegetation Index (NDVI), R2 = 0.935 y RCME = 0.746). Los resultados mostraron la aptitud y utilidad práctica de la información espectral para estimar las variables biofísicas en el cultivo de alfalfa y su monitoreo.

RESUMO As imagens AVHRR do satélite NOAA tem sido amplamente utilizadas para estudos globais devido ao baixo custo, bandas espectrais adequadas e alta resolução temporal. Os dados do sensor AVHRR (bandas 1 e 2) transformados no índice de Vegetação de Diferença Normalizada (NDVI) são os produtos mais comuns utilizados no estudo global da cobertura vegetal. As bandas 1 e 2 do AVHRR podem também ser transformadas em imagens frações (vegetação, solo e sombra) usando o modelo linear de mistura espectral para aprimorar a distinção entre os diferentes tipos de cobertura vegetal.

The primary goal of this study is to identify changes in the vegetation cover of the geopark M’goun region of Morocco, as a sample area to track the Moroccan vegetation status, and the crucial factors that influenced its evolution between 1984 and 2021. The NDVI (Normalized Difference Vegetation Index) method has been used, combined with supervised classification manipulated with the Google Earth Engine and through statistical analysis using R, together with field trips and Google Earth records for supervised classification. The percentage of vegetation density, made up of oak groves, Matorrals, red juniper, and thuja, in addition to a highly biodiverse cover, displays a declining trend. Mediumcover vegetation decreased by 29.5%, dense vegetation decreased considerably by 70.9%, and low-cover vegetation saw a minimal decline of 0.02%. As a result, dense and medium vegetation are being replaced by bare lands or poor-quality cover formed by sparse plants and solitary trees. In addition, precipitation increased slightly, showing an irregular trend, with average minimum and maximum temperatures rising by +1.7°C and +1.4°C, respectively. Furthermore, the population increased by 84.47%. Statistical analysis showed that the most important parameters affecting medium and dense vegetation cover are temperatures (Tmin and Tmax) and population density, as evidenced by the strong correlation between them. In contrast, sparse vegetation cover showed less correlation due to its heterogeneity. However, precipitation played a minimal role in vegetation evolution. Change detection maps revealed a significant negative impact on vegetation cover. This degradation was localized in the southern part of the area of study, where, according to the demographic density map, the majority of the population resides. Deforestation continues due to the lifestyle and economic activities of the local population. These factors, combined with climate change, are exerting large-scale pressure on the forest throughout the geopark. [ABSTRACT FROM AUTHOR]

Human behavior in relation to land use often has negative effects on this resource, resulting in the loss of fertility and its degradation. This, in turn, leads to a decrease in vegetation cover. Four Landsat 7 images were used corresponding to the years 2010, 2015, 2020 and 2021. The results obtained reveal that the values of the Normalized Difference Vegetation Index (NDVI) present similar trends in the coverage of the years 2015 to 2021. In this analysis, the presence of scarce and dispersed vegetation stands out. In 2015, this category experienced an increase of 0.98% compared to 2010, totaling approximately 28,866.9 hectares and covering a total area of 72,964.76 hectares. However, it is still only 4,437 hectares away from covering the entire territorial area studied. The most significant loss rate is observed in 2015, with -9.6% of dense vegetation. It is evident that the pressure of human activities on soil cover has generated a considerable increase in scarce and scattered vegetation. The spatial analysis allowed us to identify the areas with reduction or increase during the study years. [ABSTRACT FROM AUTHOR]

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Se realizó una evaluación de los cambios multitemporales en el hábitat, la percepción y amenazas sobre la zarigüeya (Didelphis marsupialis) por la comunidad asentada entre la carrera 67 y calle 2 Oeste con carrera 69 - calle 3b oeste del sector Alto de Los Chorros de la Comuna 18 de la ciudad de Santiago de Cali. Se determinaron los cambios multitemporales en la cobertura vegetal del área de estudio en los años 1961, 1986, 1998, 2001, 2007, 2012 y 2020; se cuantificó la cobertura boscosa a partir de imágenes de Google Earth y fotografías aéreas de la Corporación Autónoma Regional del Valle del Cauca (CVC). Donde se determinó el porcentaje de cobertura vegetal y el número de hectáreas en cada periodo de tiempo, por medio del programa ArcMap. En general se observó una disminución de la cobertura vegetal frondosa, pero con un incremento de los estratos arbustivo y arbóreo en el año 2001 y 2020. Por medio de entrevistas se identificaron cambios multitemporales en la percepción de los habitantes del sector sobre la zarigüeya entre 1960 y 2020. Las entrevistas también determinaron las amenazas a las que está expuesta la zarigüeya, entre ellas se destacan el atropellamiento, maltrato, pérdida de su hábitat y consumo humano.

La investigación se realizó en la Región Hidrológica 36 (ríos Nazas-Aguanaval), zona árida del norte de México. En 2017, parte de la cuenca fue alterada durante el establecimiento de pasto buffel (Cenchrus ciliaris L.) con rodillo aireador (RA). El objetivo de esta investigación fue proponer un marco metodológico para integrar y analizar la información experimental de una cuenca de zonas áridas. El impacto del RA se cuantificó mediante el uso de simulador de lluvia in situ en el área de la cuenca. Los resultados indican que el empleo de RA provoca un retraso en el inicio del escurrimiento. De igual manera, la producción de escurrimiento fue menor en la parcela donde se utilizó el RA, con una producción media de 0.000004 m3s-1, mientras que la producción media de escurrimiento en las parcelas bajo condiciones naturales (testigo) fue de 0.000016 m3s-1. Además, la producción de sedimentos en la parcela con paso de RA fue significativamente mayor en la producción de sedimentos, con un valor medio de 833 mgl-1; en tanto que en la parcela experimental bajo condiciones naturales, la producción media de sedimentos fue de 470 mgl-1. Se infiere que las microdepresiones causadas por el RA capturaron el agua de lluvia ejerciendo una mayor retención del líquido en el suelo, lo cual redujo la escorrentía y aumentó la infiltración de agua en la cuenca. Los hallazgos muestran que, debido al tamaño, la cuenca (158.87 ha) es muy sensible a los cambios en los regímenes de precipitación y la cubierta vegetal.

En la presente investigación se ha utilizado imágenes satelitales, que con el adecuado procesamiento han permitido evaluar la cobertura vegetal existente el espacio territorial del área natural protegida Santuario Nacional Los Manglares de Tumbes – Perú y que se verificó con recorrido presencial. Se pudo determinar la presencia de 7 tipos de áreas en su interior, 2 sin cobertura cuerpos de agua y zonas salitrosas – bancos de arena; y 5 con cobertura vegetal como bosque seco semidenso, bosque seco denso, manglar de franja baja, manglar de franja media y manglar de franja alta. Las coberturas de manglar ocupan la mayor parte del interior del área natural. Así mismo, en el ecosistema manglar la especie con mayor valor de índice de importancia (IVI) es la especie Rhizophora mangle y en el ecosistema bosque seco lo es la especie Caesalpinia paipai

Este trabajo tuvo como objetivo reconocer la composición y estructura de la cobertura vegetal del ecosistema del páramo de Bordoncillo a partir de la medición de parcelas circulares de 20 m de diámetro en el Páramo de Bordoncillo, determinando la limitación de la parcela y subparcela para el levantamiento de información tomando como base las variables dasométricas integrando un inventario general forestal donde se identificaron las especies de brinzales, latizales y fustales. Una vez identificadas se aplicaron los procedimientos para indicador de diversidad y su valor de importancia, de cada especie. Se concluye que el ecosistema del páramo de Bordoncillo entre los departamentos de Nariño y Putumayo, Colombia, cumple un papel muy importante en la regulación del ciclo hidrológico, el suministro de agua para el consumo humano y las actividades económicas de la zona, por ende, es primordial su conservación y protección.

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Práticas agrícolas, como o uso de plantas de cobertura inoculadas com microrganismos, objetivam transformar os sistemas produtivos em ecossistemas sustentáveis, uma vez que reduzem os impactos negativos ao ambiente e os custos de produção e, ao mesmo tempo, incrementam a produtividade das culturas principais por meio da melhoria nos atributos do solo. Este estudo objetivou determinar o efeito da aplicação de rizobactérias benéficas em plantas de cobertura cultivadas na entressafra, no acúmulo de nutrientes por essas plantas e no controle de plantas daninhas. Os experimentos foram conduzidos em área experimental em Santo Antônio de Goiás, Goiás, nas safras 2020, 2021 e 2022, com delineamento em blocos casualizados, no esquema fatorial 2x8 e quatro repetições. Os tratamentos consistiram na combinação de 8 coberturas vegetais ((1. pousio/plantas daninhas), 2. Milho, 3. Mix 1 (Tremoço Branco, Trigo Mourisco, Aveia Branca, Aveia Preta, C. ochroleuca, C. Juncea, Nabo Forrageiro, Capim coracana); 4. Mix 2 (trigo Mourisco, C. spectabiliis, nabo forrageiro, aveia preta); 5. Mix 3 (Milheto, C. ochroleuca, aveita preta, aveia branca, trigo mourisco, Capim coracana); 6. Mix 4 (C. spectabilis, trigo mourisco, milheto e C. breviflora); 7. Mix 5 (Aveia, Trigo Mourisco, Milheto, Piatã e C. Ocholeuca); e 8. Mix 6 (Aveia preta, Nabo Forrageiro, Tremoço Branco, Capim coracana, Trigo Mourisco)) com ou sem microrganismos (rizobactérias Serratia marcencens (BRM 32114) + Bacillus sp. (BRM 63573)). As avaliações consistiram no teor de nutrientes e biomassa seca da parte aérea, utilizando o teste estatístico LSD (p

Nos últimos 30 anos, a intensidade dos eventos hidrológicos mundiais apresentou significativo aumento, fato que despertou a atenção da Food and Agriculture Organization - FAO para algumas áreas do globo, como as pastagens em áreas tropicais e subtropicais. Desta forma, objetiva-se com este artigo analisar a dinâmica evolutiva do talude erosivo de uma voçoroca e sua relação com o uso e cobertura da terra, os totais pluviométricos no decorrer das estações secas e úmidas e o comportamento dos solos. Para tal, selecionou-se uma voçoroca alocada em um setor submetido a pastagens desde 1962, localizado no município de Analândia (SP). Assim, foram monitorados os dados de chuva e a evolução do talude erosivo da voçoroca durante 21 meses. Com isso, identificou-se uma dinâmica evolutiva do talude classificada como complexa, uma vez que alguns períodos de maior evolução apresentaram correspondência com os dados pluviométricos, no entanto, em outros, a evolução se relacionou de forma expressiva com o comportamento dos solos e da cobertura arbustiva/arbórea sobre o talude.

El presente artículo se desarrolla con la finalidad de analizar los cambios de uso de tierra y su impacto en la cobertura vegetal dentro del Área Natural Protegida (ANP) Parque Nacional Tingo María (PNTM) e identificar los actores y agentes territoriales vinculados a dichos cambios, entre los años 2006 y 2021. Para ello, ha sido conveniente aplicar metodologías cualitativas, mediante entrevistas semiestructuradas y una observación no participante; así como metodologías cuantitativas, mediante el procesamiento de imágenes satelitales para determinar las tasas de cambios de uso de tierra. Los resultados muestran que durante los años estudiados existen cambios en las coberturas de suelos intervenidos y la cobertura vegetal, ambos localizados en las Zonas de Uso Especial y Amortiguamiento del Parque Nacional, que están asociados a prácticas de una agricultura extensiva destinada al autoconsumo y al mercado local. En la gestión del PNTM participan la población local, organizada con los gestores del parque, las universidades e instituciones locales y regionales. Se concluye que, a través del periodo estudiado, los cambios de cobertura, a diferencia de otras ANP, no han sido significativos debido al accionar conjunto de los actores institucionales y población local que frenaron el surgimiento de actividades ilegales y no autorizadas que pudiesen impactar directamente en la cobertura vegetal del PNTM, lo que representa un modelo de gestión efectiva de un espacio natural que brinda diversos servicios ecosistémicos.

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En los últimos 20 años, Ecuador ha sufrido transformaciones en su cobertura vegetal y uso de suelo a causa del acelerado y desordenado crecimiento poblacional, han ejercido presión sobre las tierras con gran potencial. La investigación tiene como objetivo diseñar un modelo prospectivo de la Subcuenca del río Chillayacu, a partir del análisis de cambios de cobertura para el año 2030. Al procesar los datos cartográficos en el Software ArcGIS versión 10.2, se procedió al análisis de cada categoría en ambos periodos estudiados. Para el análisis de los cambios se hizo una comparación cruzada CROSSTAB en el software IDRISI selva y para el modelo prospectivo se utilizó el método de cadenas de Márkov y Autómatas Celulares de CA_Márkov. Los resultados muestran un cambio del 24.04% de la superficie y las conversiones que más destacaron fue de bosque a tierra agropecuaria con un porcentaje de 18,56%. De tal forma para el año 2030, siguen manifestándose cambios, en la zona agrícola presenta un aumento de 1330,47 ha. Sin embargo, el bosque presenta una disminución de 1368,94 ha. Actualmente, se requiere que las autoridades tomen medidas, estrategias, planificación y gestión en el ordenamiento territorial para el adecuado uso de los recursos.

Debido a la falta de métodos para estimar con precisión la pérdida de suelo en México, es necesario realizar estudios experimentales para estimar la erosión basada en datos validados. Por lo que el objetivo de esta investigación fue estimar la Tasa de Erosión Anual (A) para diversas coberturas de suelo empleando la Ecuación Universal de Pérdida de Suelo (EUPS), y ajustada mediante su relación con el índice de Generación de Sedimentos (IGS) obtenido en lotes de escurrimiento. Los resultados muestran que, durante el período y las condiciones de este estudio: EUPS subestima el valor de A al calcular la erosividad de la lluvia con el Índice Modificado de Fournier (RIMF) en los tratamientos con Vegetación Natural (VN) y Roturación con Esquilmo (RE). Los suelos sin coberturas reflejaron mayor IGS. Las ecuaciones obtenidas con la relación IGS vs A, de los tratamientos con Suelo Desnudo (SD) y Roturados (RT), pueden ser empleadas para ajustar la tasa de pérdida edáfica en suelos con características similares a las del estudio, cumpliéndose de forma parcial el objetivo de este trabajo

The acquisition of high-resolution images by drones and their subsequent processing provides valuable information on biophysical variables of grassland vegetation. The objective of this study was to generate a prediction model of the annual productivity dynamics of a semi-arid grassland in northern Mexico through the estimated vegetation cover in digital photographs obtained by drone. A permanent sampling system was designed in the La Cieneguilla cattle ranch. The study variables measured were the direct cut biomass production as the dependent variable and the vegetation cover estimated in digital images acquired by drone as the independent variable. The number of samples collected for both variables was 640 during the year 2020. With 50% of the data, the prediction model was generated and with the other 50% of the data, the validation model, the adjusted regression models were the form Y = ß0 + ß1X + ß2X2 with adjusted R2 = 71.64% and 69.90% respectively. This proposed methodology offers a non-destructive and accurate means for annual monitoring and evaluation of grasslands in dry areas. [ABSTRACT FROM AUTHOR]

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La adquisición de imágenes de alta resolución mediante drones y su posterior procesamiento proporcionan información valiosa sobre variables biofísicas de vegetación de pastizales. El objetivo de este estudio fue generar un modelo de predicción de la dinámica de la productividad anual de un pastizal semiárido del norte de México mediante la cobertura vegetal estimada en fotografías digitales obtenidas por dron. Se diseño un sistema de muestreo permanente en el predio ganadero La Cieneguilla. Las variables de estudio medidas fueron la producción de biomasa de corte directo como variable dependiente y la cobertura vegetal estimada en imágenes digitales adquiridas por dron como variable independiente. El número de muestras recogidas de ambas variables fue de 640 durante el año 2020. Con el 50% de los datos se generó el modelo de predicción y con el otro 50% de los datos el modelo de validación, los modelos de regresión ajustados fueron de la forma Y = β0 + β1X + β2X2 con R2 ajustado = 71.64% y 69.90% respectivamente. Esta metodología propuesta ofrece un medio no destructivo y preciso para el monitoreo y evaluación anual de pastizales en áreas secas.

[Introducción]: Los estudios de antropización de áreas naturales protegidas generalmente se realizan utilizando estudios de fauna, parcelas y otros indicadores. [Objetivo]: Determinar el grado de antropización de un área natural protegida usando el índice de antropización de la cobertura vegetal, que toma como unidad de evaluación el paisaje físico-geográfico. [Metodología]: La antropización se calculó a partir del índice de antropización de la cobertura vegetal, que evalúa cuantitativa y cualitativamente la modificación antrópica de los paisajes de un territorio, tomando como caso el área natural protegida Pico Azul-La Escalera, con el soporte de los paisajes físico-geográficos, lo que permite establecer su diferenciación en el territorio. [Resultados]: Los paisajes altamente antropizados representan el 2.45% del territorio, son los más planos, y muestran un predominio de la antropización por actividades agrícolas; los paisajes categorizados como antropizados ocupan el 22.36% del territorio, están relacionados con relieves de baja pendiente y suelos óptimos para la agricultura; los paisajes con calificación media cubren el 24.46% del área y sirven de zona de amortiguamiento entre los paisajes más y menos antropizados; los paisajes de valores bajos de antropización representan el 42.13% y los no modificados el 8.60% del área y representan los paisajes menos accesibles con pendientes más pronunciadas y suelos menos fértiles. [Conclusiones]: Esta propuesta es una opción confiable para diferenciar el grado de antropización de los paisajes y, en particular, para evaluar la modificación de la cobertura vegetal en un área natural protegida.

Moorland is an ecosystem of tropical high mountain regions that plays an important role in water regulation due to its climatic, orographic and biodiversity-oriented environmental conditions. However, these qualities frequently present conflicts regarding soil use due to production activities unrelated to preservation and conservation. This study analyzes the main changes in vegetation cover (periods 1986 - 2000 - 2016) that reflect edges as agricultural frontiers, in the moorland area of the Cortadera Regional Natural Park (municipality of Siachoque, Colombia). Vegetation cover types were identified using the CORINE Land Cover methodology at a scale of 1:100,000, with the satellite image processor Landsat. Representative cover types included High open forest (Baa), dense non-wooded firm ground grassland (HdTf), mosaic of pastures and crops (Mpc), lagoons, lakes and natural swamps (LlCn) and artificial water bodies (Caa). A continuous decrease of the HdTf over time was identified (from 3,604 ha in 1986, to 3,106 ha in 2000 and 2,531 ha in 2016). In contrast, Mpc cover increased by 1,447 ha in 30 years (from 1,231 ha in 1986 to 2,678 ha in 2016). It is concluded that the changes in distribution of vegetation cover types are produced by the expansion of the agricultural frontier, despite the area's declaration in 2015 as a protected area. These results demonstrate a clear need for this issue to be addressed through participatory action of stakeholders involved in the conservation process, restoration and preservation of the Cortadera moor. [ABSTRACT FROM AUTHOR]

Assessing the vegetation cover of a municipality is essential for monitoring and controlling land use and occupation. Therefore, the study aims to evaluate the evolution of areas with vegetation cover in the municipality of Guarulhos between the years 1986 and 2022, using Landsat-8 and Landsat-5 images acquired in the years 1986, 1991, 2013 and 2022. As a methodology the Normalized Difference Vegetation Index (NVDI) was applied to calculate vegetation. It is concluded that the municipality of Guarulhos has been showing a reduction in its area of vegetation cover, mainly due to irregular occupation related to the construction of the Rodoanel Trecho Norte, precisely the areas with the highest concentrations of vegetation in the municipality. [ABSTRACT FROM AUTHOR]

Introduction: Ants fulfill important ecological functions in many ecosystems and are highly sensitive to changes in land use. However, the response to these changes is poorly documented, at large spatial scales and in different land uses, in poorly studied ecosystems such as the Serranía del Perijá. Objective: To analyze the richness, diversity, and composition of ant communities in four land uses of two agroforestry landscapes of the Serranía del Perijá, Cesar, Colombia. Methods: Two sampling windows of 4 × 4 km were delimited in two agroforestry landscapes (compensation and non-compensation). In each window and landscape four land uses were chosen: forests, coffee agroforestry systems, natural regeneration and pastures, in which two trapping methods were applied: Pitfall traps and Winkler bags. Six environmental variables were measured: canopy cover, leaf litter height, bulk density, temperature, humidity and soil hardness. The sampling effort was 384 Pitfall traps and 192 m2 of leaf litter extraction. The fieldwork was conducted between February and March 2021. Results: Ants showed high sensitivity to changes in land use. Species diversity and richness decreased in land uses with less natural vegetation cover, such as pastures; while forests, in both landscapes, retained the highest species richness. Canopy cover and leaf litter availability were the environmental parameters that favored the diversity and richness of ant communities in all land uses. No differences were found between the ant composition of the two landscapes studied. Conclusions: Ants respond to changes in land use, particularly to vegetation cover. Our hypothesis was confirmed since land uses with high vegetation cover were the habitats with the greatest richness and diversity of ants. Environmental heterogeneity, a product of the dynamics of landscape transformation, is an element that should be considered in future research. [ABSTRACT FROM AUTHOR]

Contextualization: Wetlands are deteriorated, mainly due to human activities that cause degradation processes in the wetlands, due to changes in land use, causing conflicts between people living near to the wetlands, as well as consequences in the supply of resources for the population. Anthropic activities affect water resources, which limits the ecosystem services that wetlands provide. Knowledge gap: There is no information about the availability of water resources in the wetland area, that information would contribute for an efficient and inclusive water governance in the area and could support the formulation of public policies about the integrated management of water resources, thus it would maximize social and economic welfare in the municipality. To achieve those objectives, it is necessary to determine the mentioned availability to conserve the wetland ecosystems of regional importance. Purpose: This research estimated the [net] available surface water supply, using the rainfall-runoff method, in El Gallinazo wetland, located on Aguachica (Cesar-Colombia), as a contribution to the integral management of the hydric resource. Methodology: It was identified the vegetation cover of the area, using the Corine Land Cover method adapted for Colombia, the hydrological group was determined by examining the soil texture; with these two inputs the number of curves was determined through tables. The research included the calculation of the mean annual precipitation, using the Kriging interpolation method, with the help of ArcGIS software and the meteorological data extracted from IDEAM stations to determine the effective precipitation of the area. In addition, the rainfall-runoff method, based on the number of curves (SCS-CN), and the resolution 865 of 2004 were used to establish the net available water supply of El Gallinazo wetland. Results and conclusions: The area has two types of vegetation cover, three hydrologic soil groups, and an average NC of 59,29, demonstrating a moderately high runoff potential and a moderate infiltration capacity; the available annual water supply was estimated at 42573,6 m³. The behavior of water availability depends on the anthropic activities developed inside and outside the wetland, as well as on the precipitation regime. [ABSTRACT FROM AUTHOR]

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La zona andina de la provincia de El Oro (ZAEO), pertenece a la región sur del Ecuador, que se caracteriza de una gran variabilidad y diversidad biológica. El objetivo de este estudio fue analizar los cambios de cobertura vegetal y uso de suelo en la ZAEO. Se usó dos imágenes Sentinel-2 (MSI) de nivel 1C, para el periodo 2017-2020. Se realizó una clasificación supervisada de máxima verosimilitud, en un rango altitudinal desde los 900 a 3900 msnm, usando 4 de las 6 clases de nivel 1 propuestas por el Ministerio del Ambiente del Ecuador, para cada clase se elaboró 16 áreas de entrenamiento (ROI). Se obtuvo una precisión general de 0.855 para el 2017 y de 0.944 para el 2020. Se utilizó 120 pixeles para la elaboración de la matriz de confusión, donde el índice Kappa para el 2017 fue de 0.6870, mientras que para el 2020 fue de 0.9058. Por último, la tasa de cambio entre el 2017 y 2020, se registraron incrementos en las clases: bosques (BO), zona antrópica (ZA) y vegetación arbustiva y herbácea (VAH), con valores de 43.90%, 9.52% y 4.22%, respectivamente, mientras que tierra agropecuaria (TA) registró pérdidas del 9.43%.

Contextualización: Hoy en día los humedales se encuentran en deterioro a causa principalmente de las actividades antrópicas que provocan procesos de sustitución y degradación por el cambio en los usos de los suelos causando conflicto de uso así como consecuencias en el suministro de los recursos. En especial, el recurso hídrico el cual presenta diversas alteraciones lo que limita los servicios ecosistémicos que los humedales prestan. Vacío de conocimiento: Información inexistente sobre la disponibilidad del recurso hídrico en la zona del humedal que sirve de base para la gobernanza del agua eficaz, eficiente e incluyente en la zona, permitiendo contribuir en la formulación de políticas públicas en la gestión integral del recurso hídrico maximizando así el bienestar social y económico en el municipio, y se hace necesario la determinación de esta con el fin de conservar los ecosistemas periurbanos de importancia regional. Propósito: Este trabajo se estimó la oferta hídrica superficial neta disponible mediante el método lluvia-escorrentía, en el humedal El Gallinazo, Aguachica (Cesar – Colombia) como aporte a la gestión integral del recurso. Metodología: Se basó en el establecimiento de la cobertura vegetal por medio del sistema Corine Land Cover adaptado para Colombia, el grupo hidrológico mediante la textura del suelo y con esto se determinó a través de tablas el número de curvas. La investigación incluyó el cálculo de la precipitación media anual empleando el método de interpolación de Kriging con ayuda del software ArcGIS y datos meteorológicos extraídos de estaciones del IDEAM, para luego determinar la precipitación efectiva de la zona. Además, se utilizó el método lluvia-escorrentía en función al número de curvas (SCS-CN) y la resolución 865 de 2004 para establecer la oferta hídrica neta disponible del humedal El Gallinazo. Resultados y conclusiones: La zona posee dos tipos de coberturas vegetales, tres grupos hidrológicos de suelo y un CN promedio de 59,29 demostrando un potencial de escorrentía moderadamente alto y una capacidad de infiltración moderada; la oferta hídrica anual disponible fue de 42573,6 m3. El comportamiento de la disponibilidad del agua depende de las actividades antrópica dentro y fuera del humedal así como del régimen de precipitación.

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Copyright of Revista Chapingo Serie Ciencias Forestales is the property of Universidad Autonoma Chapingo 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.)

Seeding pastures or forage crops by no-tillage methods usually involves the spray of glyphosate to suppress the existing vegetation. While many studies found detrimentaleffects of glyphosate on seed germination and seedling growth of the subsequent crop, others found negligible effects. This study aimed to evaluate the effect of glyphosate spraying on germination, seedling emergence and seedling growth of four forage species: Trifolium repens, Lotus tenuis, Festuca arundinacea and Paspalum dilatatum. The experiment was carried out spraying glyphosate on the pre-existing vegetation and on bare soil 1, 30, 60 and 90 days before sowing, and a control treatmentsprayed with water. Glyphosate sprayed on pre-existing vegetation 1 to 60 days before seeding reduced emergence, while sprayed 1 to 30 or 1 to 60 days before seeding reduced seedlings belowground biomass and root length of all species and aboveground biomass of legumes respect to sprayed 90 days before seeding, sprayed on bare soil, and control treatment. This herbicide would remain active in the soil environment for at least 60 days after spraying when it was previously absorbed by plants, causing a severe damage to seedlings emergence and growth. Highlights: • Glyphosate sprayed on pre-existing vegetation 1 to 60 days before seeding reduced seedling emergence of Trifolium repens, Lotus tenuis, Festuca arundinacea and Paspalum dilatatum. • Glyphosate sprayed on pre-existing vegetation 1-30 or 1-60 days before seeding reduced seedlings belowground biomass and root length of all species and aboveground biomass of legumes • Gyphosate sprayed 90 days before seeding or sprayed on bare soil did not affect seggling emergence and growth. • Gyphosate would remain active in the soil environment for at least 60 days after spraying when it was previously absorbed by plants.

El presente trabajo de investigación aborda, desde el enfoque paisajístico, el estudio de la cubierta vegetal en zonas de transición del Distrito Pampeano Austral. Se propone analizar la distribución de la vegetación representativa de un sector de espacios lacustres del sudoeste de la provincia de Buenos Aires, Argentina. Dado que la vegetación presenta cualidades que permiten identificar y diferenciar patrones espaciales e impactos territoriales, el estudio resulta apropiado para la interpretación paisajística del área de estudio. El relevamiento se realizó mediante trabajo de campo, se aplicó el método cuadrados de vegetación en seis unidades de muestreo. Se realizó una revisión bibliográfica de material especializado en el reconocimiento de plantas para la identificación de las mismas; además, se diseñó una planilla de relevamiento a fin de sistematizar información que permita especificar las características y el medio en el cual se desarrollan las especies, como también su distribución espacial. Los resultados registraron mayor presencia de especies nativas sobre introducidas, no obstante, cabe destacar que la flora nativa evidencia una significativa intervención antrópica en toda la región, producto del desarrollo de actividades agro productivas. Se observó un predominio exclusivo del estrato herbáceo, siendo las gramíneas las de mayor representatividad y cobertura. En este caso, se destaca la familia Poaceae con paja vizcachera o pasto puna (Stipa ambigua), gramilla o pata de perdiz (Cynodon dactylon) y cola de zorro (Setaria parviflora) como las especies más representativas. Abordar el estudio de la vegetación con una perspectiva paisajística resulta un aporte relevante orientado a obtener mayor conocimiento del área de estudio en pos de definir el potencial del paisaje que la caracteriza para diseñar propuestas de uso, manejo y conservación del mismo.

Studying the role of mycorrhyzae for supporting ecological processes and the stability and aggregation of soil is of great importance in the ecosystems of the Andean region undergoing high transformation. This study evaluated the importance of the arbuscular mycorrhizal fungi (AMF) through the traits of spore density, external mycelium length (EML), and glomalin concentration on the aggregation indices and the physical and chemical characteristics in 20 patches classified in four land uses (forest, stubble, coffee plantations, and cattle pastures) in the high basin of Cali River (Colombia). The traits of EML, difficult-extractable glomalin-related soil protein (DE-GRSP), and total glomalin-related soil protein (T-GRSP), were significantly higher in forest, stubble and coffee soils, which, in turn, presented the highest soil aggregation values. On the other hand, the soils from cattle pastures presented a significantly higher percentage of microaggregates, macroaggregates, spore density and easily-extractable glomalin-related soil protein (EE-GRSP) than the other land uses which suggests adverse effects from compaction and erosion. The higher proportion of stable macroaggregates suggests that the AMF improve soil conditions during the agglutination of particles in stable aggregates due to glomalin. Although it is evident how the effects of some mycorrhizal traits can improve the soil conditions, in other agroecosystems, these effects are affected by the type of agricultural activity and the intensity of soil tillage. Similarly, other ecosystem processes involved in the regulation of fertility and the transformation of organic matter can also be affected. [ABSTRACT FROM AUTHOR]

A plant diversity study was conducted in the district of Cajatambo with emphasis on the agricultural and shrubland ecosystems. The records were made during 2015 and 2016 using 44 transects of 30 meters, in 9 plant formations. The alpha diversity in agricultural areas such as Parientana, Urpaycocha and Tizapampa grass were highly variable over time, but with low plant diversity, while the scrublands near the quarry and mine and the grasslands of Tocanca and road to Viconga were less variable and with higher diversity. The results suggest that an important factor for this behavior is the degree of human intervention. Beta diversity showed two large groups separated by altitude: one with agricultural zones and scrublands and the other with high Andean ecosystems. Both the agricultural zones and the scrublands showed that only in the dry periods of each year were some transects again quite similar (more than 80%), although others were less similar (62%). The presence and persistence of species during both dry seasons such as Trifolium repens, Rumex obtusifolius, Plantago lanceolata, Medicago sativa, Medicago polymorpha and Taraxacum officinale in the agricultural areas, as well as Minthostachys mollis, Ophryosporus peruvianus, Austrocylindropuntia subulata, Ribes viscosum, Acaena torilicarpa, Mutisia acuminata and Muehlenbeckia volcanica in the scrublands, is of great importance not only in the dynamics, but also in the management of the system because it includes species that are used by the inhabitants of Cajatambo. [ABSTRACT FROM AUTHOR]

Land use change studies are very important tools because they evaluate the speed of deforestation/reforestation, determine its geographic extension and comprehend the social and economic causes of the changes at global, regional and local scales. The objective of this work was to analyze land use changes in the Guangras sector, in an area of 1 609.48 ha focused on to the recovery of ecosystem services and biodiversity conservation in the southern zone of the eastern Andean Cordillera within Sangay National Park. A spatio-temporal study was carried out through satellite images, where Landsat images were pre-processed and classified using ArcGis 10.1 software to determine the change in land use and the analysis of the transition matrix. As a result of this geospatial study, five land uses were identified: moorland, agricultural crops, forest, grassland and water bodies, as well as a change dynamic from 1991 to 2016, in relation to the forest, a decrease of 2.47 %, of moorland 0.76 %, of water bodies 0.28 %, while grassland increased by 3.07 %, and agricultural crops by 1.88 %. [ABSTRACT FROM AUTHOR]

This study evaluated soil organic carbon sequestration (SOC) in four vegetation covers (secondary vegetation [VS], forest plantations of Eucalyptus globulus (EUC) and Pinus patula [PIN] and pastures [PAS]), and its correlation with the physicochemical properties of the soil. Soil samples were taken at two depths in the A horizon (0-10 and 10-20 cm). Soil physicochemical variables were measured to evaluate their relationship with changes in SOC sequestration. We found that the highest SOC storage was in horizon A of EUC (100.5 ton C ha−1), followed by PAS (75.55 ton C ha−1), PIN (66.70 ton C ha−1) and SV (56.53 ton C ha−1). The SOC was significantly and positively correlated with the maximum water retention capacity, structural stability index, content of sand, clay, and carbon in humic and fulvic acids. However, SOC was negatively correlated with apparent density, state of aggregation, silt content, pH and CICE. These results suggest that cover change significantly affects SOC sequestration, soil organic matter characteristics, and soil physicochemical properties. [ABSTRACT FROM AUTHOR]

Seeding pastures or forage crops by no-tillage methods usually involves the spray of glyphosate to suppress the existing vegetation. While many studies found detrimental effects of glyphosate on seed germination and seedling growth of the subsequent crop, others found negligible effects. This study aimed to evaluate the effect of glyphosate spraying on germination, seedling emergence and seedling growth of four forage species: Trifolium repens, Lotus tenuis, Festuca arundinacea and Paspalum dilatatum. The experiment was carried out spraying glyphosate on the pre-existing vegetation and on bare soil 1, 30, 60 and 90 days before sowing, and a control treatment sprayed with water. Glyphosate sprayed on pre-existing vegetation 1 to 60 days before seeding reduced emergence, while sprayed 1 to 30 or 1 to 60 days before seeding reduced seedlings belowground biomass and root length of all species and aboveground biomass of legumes respect to sprayed 90 days before seeding, sprayed on bare soil, and control treatment. This herbicide would remain active in the soil environment for at least 60 days after spraying when it was previously absorbed by plants, causing a severe damage to seedlings emergence and growth. [ABSTRACT FROM AUTHOR]

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Copyright of Revista Chapingo Serie Ciencias Forestales is the property of Universidad Autonoma Chapingo 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.)