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At present, one of the main worldwide problems is the fact related to soil classification and its correlation with the others currently existing, in order to create a universal language, which is a very important aspect on soil preservation and management. Our country is not free from it, since there are serious problems when our soils are characterized and mainly classified, mostly in agriculture. Having in mind what was said above and based on a study through establishing a reference sector and the combined application of a geographical information system, they proceeded to determine soil characterization, classification and distribution in "La Rosita" farm, located at the East of Havana City, as well as soil surface (ha) and the percentage occupied inside the estate. A soil map was devised, where soils were classified until species level, resulting that the main groups present were: Cambisols, Vertisols and Phaeozems. [ABSTRACT FROM AUTHOR]

At present, there is a tendency to confuse different limiting factors, which are intrinsic to the soil due to its own process of formation, with the process of degradation provoked by the anthropic action; it is an essential aspect that should be considered when characterizing and classifying soils. Based on a study conducted after establishing a Reference Sector and the joint application of a Geographic Information System, the main limiting factors were determined and characterized in La Rosita farm soils, as well as the surface area (ha and %) taken up. The farm is located in Habana del Este at the City of Havana. It was obtained that the most important limiting factors in this location were: effective depth, degree of erosion, organic matter and slope. [ABSTRACT FROM AUTHOR]

The present concepts of Global Soil Change (GSC) are exposed in this work, and applied to Rhodic Eutrhic Nitisols, represented in Havana province. Based on the study of 10 soil profiles (FRL), with different land uses (from soils under permanent grove of ficus, soils under fruit groves for 30 years, soils previously cultivated and now with grass, and soils under intensive culture for more than 30 years), changes appearing in the properties of this type of soil were determined, mainly its color, structure, amount of organic matter, dispersal factor, bulk density, total porosity and exchangeable cations. At the same time, one hypothesis is presented about the process that is happening in the last 15-20 years, with pH increase in these soils, in intensive culture areas of Havana province. By this hypothesis, it was determined that pH increase is due to soil functioning, its intensive culture with irrigation application and the climatic change that is happening in Cuba in the last 50 years, due mainly to the increase of 0.6°C in the mean annual temperature and 1.6°C in the daily minimum temperature. [ABSTRACT FROM AUTHOR]

In order to determine the diversity of phytophagous and predators mites in agroecosystems of the farms "El Caimito" and "Dos Rosas", Cotorro municipality, Havana, Cuba, periodic samplings were carried out from February 2018 to March 2019. In all the samplings, 100 simple leaves per plant were selected, which were reviewed under a stereoscopic microscope (Carl ZeissTM, StemiTM DV4 model). The collected adult mites were clarified and mounted on slides. For their identification, they were observed with a Carl ZeissTM microscope, model AxioSkope.A1 and the corresponding taxonomic keys were used. The relative abundance and frequency of each species were calculated, the species accumulation curve was made and the ecological indices were determined by type of ecosystem. As a result of the inventory, eleven families of mites were detected. The phytophagous mites were represented by three families (Tarsonemidae, Tetranychidae and Tenuipalpidae) and six morphospecies, five families of predatory mites (Bdellidae, Cunaxidae, Stigmaeidae, Eupodidae and Phytoseiidae) with 17 morphospecies and four families of mites with varied eating habits (Acaridae, Tarsonemidae, Tydeidae, and Oppidae). The no disturbed ecosystem, represented by plant species in natural habitats, was the most diverse. Agroecosystem management practices were shown to influence the relative abundance and frequency of species, impacting the diversity of ecosystems. [ABSTRACT FROM AUTHOR]

In order to determine the diversity of mites in the farm "Las Piedras", Guanabacoa municipality, Havana Province, Cuba, periodic sampling was carried out between June 2018 and April 2019. In each sampling, 100 simple leaves per plant species were selected, which were examined under a stereoscopic microscope (Carl ZeissTM, StemiTM DV4 model), and the adult mites were clarified and mounted on slides. The corresponding taxonomic keys were used for their identification. The relative abundance and frequency of each species were calculated, the species accumulation curve was made by the Clench equation and the ecological indices by types of ecosystem were calculated. As a result of the inventory, nine families of mites were detected; two of them were phytophagous mites (Tarsonemidae and Tetranychidae), four of predatory mites (Bdellidae, Cunaxidae, Stigmaeidae and Phytoseiidae) and three of mites with varied feeding habits (Acaridae, Tydeidae and Oppidae). The parameters and values estimated by the Clench species accumulation model indicated that the inventory results were reliable. A differential behavior was observed in the relative abundance and frequency of the phytoseid mite species as a function of the management of the ecosystems. The species I. quadripilis were very abundant and very frequent in the undisturbed ecosystem, while E. hibisci and Agistemus sp., were very abundant and frequent in the little disturbed ecosystem. The little disturbed ecosystem, represented by the fruit species, was the most diverse. Among the detected species, I. quadripilis and E. hisbisci stood out for presenting the greatest possibilities of use as biological control agents of harmful organisms in the farm "Las Piedras". This knowledge will make possible to establish the most favorable agroecosystem management practices for the conservation of these important natural enemies. [ABSTRACT FROM AUTHOR]