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1.
Braz. j. biol ; 76(3): 700-707, tab, graf
Artículo en Inglés | LILACS | ID: lil-785024

RESUMEN

Abstract Assess the state of public green areas, their importance and influence on environmental quality and living in urban centers is an arduous task considering the conceptual and scientific regarding quantification and data analysis methods divergence. In this study, we aimed to determine two indicators of public green areas relative to the percentage of public green areas (PPGA) and the public green areas index (PGAI) in the urban area of São Carlos, SP. The study area was organized into administrative regions (ARs), using satellite images, topographical maps of 1:10,000 Geographic and Cartographic Institute (1990) and data provided by the Municipality of São Carlos. The results show that public green areas comprise 6.55% of the municipality, with a public green areas index (PGAI) of 18.85 m2/inhabitant, indicating good urban environmental quality when compared to rates of 15 m2/capita for public green areas for recreation, suggested by the Brazilian Society of Urban Forestry. The differences between the administrative regions are concern with situations from 4.16 to 36.30 m2/inhabitant. In this context, it is recommend specific public policies and popular participation in the process of continuous improvement for increasing public green areas in the less favored regions. The Genebrino method applied to indicators of public green areas (GPGA – amount of public green areas divided by population density), showed a commendable goal above 40% for urban environmental quality.


Resumo Diagnosticar a situação das áreas verdes públicas, sua importância e influência na qualidade ambiental e de vida nos centros urbanos é uma tarefa árdua, considerando a divergência conceitual e de métodos científicos no que tange a quantificação e a análise dos dados. Neste estudo, objetivou-se determinar dois indicadores de áreas verdes públicas, referentes ao percentual de áreas verdes públicas (PAVP) e ao índice de áreas verdes públicas (IAVP) no perímetro urbano do Município de São Carlos, SP. A área de estudo foi organizada em regiões administrativas (RAs), utilizando imagens de satélite, cartas topográficas 1:10.000 do Instituto Geográfico e Cartográfico (1990) e dados fornecidos pela Prefeitura Municipal de São Carlos. Os resultados demonstram que as áreas verdes públicas compreendem 6,55% do território do município, com um índice de áreas verdes públicas (IAVP) de 18,85 m2/habitante, indicando uma boa qualidade ambiental urbana quando comparado aos índices de 15 m2/habitante para áreas verdes públicas destinadas à recreação, sugerido pela Sociedade Brasileira de Arborização Urbana. As diferenças entre as regiões administrativas são preocupantes, com situações de 4,16 a 36,30 m2/habitantes. Neste contexto, recomendam-se políticas públicas específicas e a participação popular no processo de melhoria contínua para o incremento das áreas verdes públicas nas regiões menos favorecidas. O método genebrino, aplicado aos indicadores de áreas verdes públicas (IAVP – somatório das áreas verdes públicas dividido pela densidade populacional), apontou uma meta recomendável acima de 40% para a qualidade ambiental urbana.


Asunto(s)
Humanos , Bosques , Monitoreo del Ambiente/métodos , Monitoreo del Ambiente/estadística & datos numéricos , Ciudades , Parques Recreativos/normas , Parques Recreativos/estadística & datos numéricos , Población Urbana , Urbanización , Brasil , Densidad de Población
2.
Braz J Biol ; 76(3): 700-7, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-27097087

RESUMEN

Assess the state of public green areas, their importance and influence on environmental quality and living in urban centers is an arduous task considering the conceptual and scientific regarding quantification and data analysis methods divergence. In this study, we aimed to determine two indicators of public green areas relative to the percentage of public green areas (PPGA) and the public green areas index (PGAI) in the urban area of São Carlos, SP. The study area was organized into administrative regions (ARs), using satellite images, topographical maps of 1:10,000 Geographic and Cartographic Institute (1990) and data provided by the Municipality of São Carlos. The results show that public green areas comprise 6.55% of the municipality, with a public green areas index (PGAI) of 18.85 m2/inhabitant, indicating good urban environmental quality when compared to rates of 15 m2/capita for public green areas for recreation, suggested by the Brazilian Society of Urban Forestry. The differences between the administrative regions are concern with situations from 4.16 to 36.30 m2/inhabitant. In this context, it is recommend specific public policies and popular participation in the process of continuous improvement for increasing public green areas in the less favored regions. The Genebrino method applied to indicators of public green areas (GPGA - amount of public green areas divided by population density), showed a commendable goal above 40% for urban environmental quality.


Asunto(s)
Ciudades , Monitoreo del Ambiente/métodos , Monitoreo del Ambiente/estadística & datos numéricos , Bosques , Parques Recreativos/estadística & datos numéricos , Parques Recreativos/normas , Brasil , Humanos , Densidad de Población , Población Urbana , Urbanización
3.
Braz J Biol ; 75(3): 511-6, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26465720

RESUMEN

Estuaries present an environmental gradient that ranges from almost fresh water conditions to almost marine conditions. Salinity and flooding are the main abiotic drivers for plants. Therefore, plant zonation in estuaries is closely related to the tidal cycles. It is expected that the competitive abilities of plants would be inversely related to the tolerance toward environmental stress (tradeoff). Thus, in estuaries, plant zonation tends to be controlled by the environment near the sandbar and by competition away from it. This zonation pattern has been proposed for regular non-tropical estuaries. For tropical estuaries, the relative importance of rain is higher, and it is not clear to what extent this model can be extrapolated. We measured the tidal influence along the environmental gradient of a tropical irregular estuary and quantified the relative importance of the environment and the co-occurrence degree. Contrary to the narrow occurrence zone that would be expected for regular estuaries, plants presented large occurrence zones. However, the relative importance of the environment and competition followed the same patterns proposed for regular estuaries. The environmental conditions allow plants to occur in larger zones, but these zones arise from smaller and infrequent patches distributed across a larger area, and most species populations are concentrated in relatively narrow zones. Thus, we concluded that the zonation pattern in the Massaguaçu River estuary agrees with the tradeoff model.


Asunto(s)
Inundaciones , Dispersión de las Plantas , Salinidad , Brasil , Estuarios , Modelos Biológicos
4.
Braz J Biol ; 75(3): 709-17, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26465731

RESUMEN

Vegetation coverage can be inappropriately used, especially in the absence of proper planning, and can result in a reduction of the occupied area. Demographic and economic alterations are factors that contribute to the degradation of vegetation coverage in landscape units. In addition, because vegetation is essential for protection of recharge areas in aquifers, the fragmentation of habitats in hydrographic basins causes changes in climate temperature, soil erosion, eutrophication, and siltation of watercourses. This study analyzed the vegetation coverage from the municipality of São Carlos, State of São Paulo (SP) to assess the environmental quality of water resources in the hydrographic basins and sub-basins, in the Guarani Aquifer System. The vegetation coverage was analyzed in three scales: municipality, Hydric Resource Management Units (UGRHIs), and hydrographic sub-basins based on map overlapping from the LAPA/UFSCar Digital Cartographic Collection and visual interpretation of LANDSAT 5, TM sensor, Path 220, row 075 on satellite images. The municipality of São Carlos has vegetation coverage of 31,776.4 hectares, in which 57% is classified as preserved vegetation typology, and 58% is over the Guarani aquifer recharge area. The vegetation coverage with savannas, riparian forests, and mesophyll forests represented 28% of the total studied area and is located over 28.3% of the Guarani aquifer recharge area extension. The Permanent preservation areas (PPAs) represent 21.6% of the total vegetation coverage with 51% of it being vegetated. The municipality has a total of 686 springs (Topographic maps of IBGE, escale 1:50,000) distributed on an average of 60 springs per km2; 40% of these are protected by vegetation.


Asunto(s)
Bosques , Dispersión de las Plantas , Brasil , Clima , Temperatura
5.
Genet Mol Res ; 13(4): 9044-55, 2014 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-25366795

RESUMEN

Tephrosia cinerea L. (Pers.) is a tropical species that exhibits antileishmanial activity in Leishmania amazonensis promastigote cultures and is commonly used to treat infections, inflammations, ulcers, nervous conditions, and diarrhea. However, no studies have investigated its effects on genetic material. Therefore, we evaluated the genotoxic potential, antigenotoxic potential, and cytotoxic effects of hydroalcoholic extracts of T. cinerea leaves. In an in vitro genotoxicity study, human peripheral blood leukocytes were treated for 3, 24 (comet assay), or 48 h (cell death assay) with 22, 44, or 88 µg/mL plant extract. In the in vivo assay, Swiss mice were treated with 500, 1000, or 2000 mg extract/kg body weight by intraperitoneal injection and were evaluated 24 h later. Antigenotoxicity was investigated in pre- and post-treatment assays in which the animals received the plant extract (2000 mg/kg) 24 h before or after receiving cyclophosphamide (50 mg/kg), respectively. The extract had no genotoxic effects in the in vitro or in vivo assays. However, the extract reduced apoptotic cell death and induced necrotic cell death at concentrations that presented leishmanicidal activity in vitro. The extract also had an antigenotoxic effect, reducing the levels of genomic damage that were caused by cyclophosphamide in Swiss mice by more than 80%.


Asunto(s)
Ciclofosfamida/toxicidad , Daño del ADN/efectos de los fármacos , Extractos Vegetales/farmacología , Tephrosia/química , Animales , Antiprotozoarios/administración & dosificación , Antiprotozoarios/farmacología , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Ensayo Cometa , Relación Dosis-Respuesta a Droga , Humanos , Inyecciones Intraperitoneales , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/efectos de los fármacos , Ratones , Mutágenos/toxicidad , Fitoterapia , Extractos Vegetales/administración & dosificación , Sustancias Protectoras/administración & dosificación , Sustancias Protectoras/farmacología
6.
Braz J Biol ; 74(3 Suppl 1): S64-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25627367

RESUMEN

The Brazilian cerrado presents strong climate seasonality. During the dry season, plants may be exposed to stressful situations, such as a soil surface water deficit, that stimulate their chemical defenses. However, the seasonality effect on the production of allelopathic compounds of cerrado plant species is poorly understood. In this study, the phytotoxic activities of common native cerrado plants were evaluated during rainy and dry seasons. Crude leaves extracts (10% concentration: weight/volume, with dry leaves and distilled water) from eleven species were tested on lettuce and sesame germination. The negative effects on germination percentages, rates and informational entropies of the target species were higher when submitted to plant extracts from the dry season, where the germination rate was the most sensible parameter. The higher sensibility of lettuce and the germination rate parameter showed this difference. Only two exceptions had higher effects for rainy season extracts; one species showed higher negative effects on germination informational entropy of lettuce and another species on the germination rate of sesame. Thus, increases in the allelopathic activity were seen in the majority of the studied cerrado plant species during the dry season. These distinct responses to stressful situations in a complex environment such as the Brazilian cerrado may support the establishment and survival of some species.


Asunto(s)
Alelopatía/fisiología , Estaciones del Año , Árboles/fisiología , Brasil , Árboles/clasificación
7.
Genet Mol Res ; 12(2): 1132-42, 2013 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-23661438

RESUMEN

Julocroton triqueter extracts have antileishmanial activity; however, the effect on genetic stability has not been studied. We evaluated genotoxic and cell death induction potential (in vitro and in vivo) of J. triqueter var. triqueter hydroalcoholic extracts, as well as their antigenotoxic potential in vivo. The in vitro genotoxic studies were performed using human leukocytes at four different concentrations. For the in vivo tests, Swiss mice were treated with 125, 250 or 500 mg/kg of extract injected intraperitoneally. Antigenotoxic effects of the extract were measured before and after cyclophosphamide treatment. An absence of genotoxic effects was observed both in vitro and in vivo. In the antigenotoxic studies, no significant difference was observed between the treatments and the positive control, indicating that the extracts did not protect against damage caused by cyclophosphamide. Hydroalcoholic extracts of J. triqueter did not provoke DNA damage at concentrations and doses normally used for antileishmanial treatment; however, they reduced apoptotic cell death and induced necrotic cell death.


Asunto(s)
Antiprotozoarios/toxicidad , Croton/química , Leishmania/efectos de los fármacos , Extractos Vegetales/toxicidad , Animales , Antiprotozoarios/química , Muerte Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayo Cometa , Femenino , Humanos , Leucocitos/efectos de los fármacos , Leucocitos/metabolismo , Masculino , Ratones , Pruebas de Mutagenicidad , Extractos Vegetales/química
8.
Braz J Biol ; 66(2B): 587-602, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16906291

RESUMEN

Secondary succession in degraded areas is little studied, especially where long-term observation of evolutionary processes is concerned. The aim of this work was to follow the qualitative and quantitative changes in vegetation throughout the regeneration process after fire in a cerrado with forest physionomy. The area under study is a reserve on CPPSE-EMBRAPA's farm, São Carlos region of São Paulo State, Brazil. In 1981, an especially destructive fire eliminated the aerial part of the vegetation and litter. From that time, the vegetation in three permanent quadrats of 2 x 20 m was recorded for twenty years. The results demonstrated the rapid growth of herbs, shrubs, climbers and trees successively, with a great species richness and, after a certain time, a decline in density at a rate similar to the initial recovery. Both the soil seed bank and sprouting subterranean organs played important parts in the recovery of the vegetation. Three phases were observed in the plant succession: plant growth, followed by intraspecific competition with a reduction in the number of individuals and finally interspecific competition with the disappearance of some species from the quadrats. The different populations behaved similarly and the rise and fall in density of each species over time reflected their ecological role.


Asunto(s)
Incendios , Desarrollo de la Planta , Brasil , Plantas/clasificación , Densidad de Población
9.
Braz. j. biol ; 66(2b): 587-602, May 2006. tab
Artículo en Inglés | LILACS | ID: lil-433144

RESUMEN

A sucessão secundária em áreas degradadas é pouco estudada, principalmente em relação ao acompanhamento dos processos evolutivos por longo período. O objetivo deste trabalho foi de verificar as mudanças qualitativas e quantitativas da vegetação durante o processo de regeneração após fogo em um cerrado com fisionomia de cerradão. A área estudada pertence a uma reserva institucional da CPPSE EMBRAPA, São Carlos, SP, Brasil. No ano de 1981 ocorreu um incêndio de proporções elevadas eliminando todo o folhedo e o dossel. O acompanhamento foi realizado em três parcelas fixas de 2 x 20 m ao longo de vinte anos. Os resultados demonstraram um rápido estabelecimento de indivíduos sucessivamente com plantas herbáceas, arbustivas, lianas e arbóreas, uma grande riqueza em espécies e, depois de determinado tempo, uma regressão em densidade na mesma ordem de estabelecimento. O banco de sementes do solo e o rebrotamento subterrâneo tiveram papel importante na recuperação da vegetação. No processo sucessional ocorreram três fases sucessivas: estabelecimento de plantas; competição intra-específica devido ao reajuste no número de indivíduos por espécies e competição interespecífica com a eliminação de algumas espécies das parcelas. As populações analisadas apresentaram padrões semelhantes de comportamento e a maior ou menor densidade ao longo do tempo refletiu o comportamento ecológico das espécies.


Asunto(s)
Incendios , Plantas/crecimiento & desarrollo , Brasil , Densidad de Población , Plantas/clasificación
10.
Braz. j. biol ; 63(3): 527-536, Aug. 2003. mapas, tab
Artículo en Inglés | LILACS | ID: lil-353976

RESUMEN

A map of the native vegetation remaining in São Carlos County was built based on aerial images, satellite images, and field observations, and a projection of the probable original vegetation was made by checking it against soil and relief surveys. The existing vegetation is very fragmented and impoverished, consisting predominantly of cerrados (savanna vegetation of various physiognomies), semideciduous and riparian forest, and regeneration areas. Araucaria angustifolia (Bertol.) Kuntze, found in patches inside the semideciduous forest beginning at a minimum altitude of 850 m, has practically disappeared. By evaluating areas on the map for different forms of vegetation, we obtained the following results for original coverage: 27 percent cerrado (sparsely arboreal and short-shrub savanna, and wet meadows); 16 percent cerradäo (arboreal savanna); 55 percent semideciduous and riparian forests; and 2 percent forest with A. angustifolia. There are now 2 percent cerrados; 2.5 percent cerradäo; 1 percent semideciduous forest and riparian forests; 1.5 percent regeneration areas; and 0 percent forest with A. angustifolia.


Asunto(s)
Variación Genética , Árboles , Brasil , Densidad de Población
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