Levantamento de animais silvestres atropelados em trecho da rodovia BR482 / Survey of road-killed wild animals in stretch of the highway BR482

The objective of this study was to evaluate the occurrence of wild animals found run over on the highway BR482 in the stretch between the cities Conselheiro Lafaiete and Viçosa, Minas Gerais, Brazil. The average of run over was 0.010 animals/km traveled. The mammals represented the most hit, followed by birds, amphibians and reptiles. This work, pioneered in this region, presents the species most affected by the traffic in the highway BR482 and contributes to a preliminary assessment of the present fauna of this region and the anthropological impact along that stretch.

Response of understory vegetation to exclosure in a heavily compacted forest recreational site.

Objectives of this study were to investigate effect of exclosure on understory vegetation recovery and determine the time required for understory vegetation recovery in a forest recreational site. Recovery of understory vegetation in an exclosure was monitored for three growing seasons and plant density and vegetation cover were determined for each plant species. Exclosure was compared with control plot for the Shannon index of diversity. Results showed that a total of 33 (18 woody, 15 herbaceous) plant taxa were established in the exclosure while 42 (16 woody, 26 herbaceous) were encountered in the forest plot. Quercus petraea (Mattuschka) Liebl. subsp. iberica (Steven ex Bieb.) Krassiln. had the highest density both in the exclosure (30.37 plants m-2) and forest plot (25.75 plants m-2) and followed by Hedera helix L. (28.44 plants m-2 in the exclosure, 23.33 plants m-2 in the forest plot). Plant species recovered in the exclosure did not survive very long as growing season progressed, top soil dried, and canopy closure increased. H. helix L. was the major dominant plant species for vegetation cover in both exclosure (45.23 %) and forest plot (45.08 %). There was a significant difference between plots for species diversity and forest plot had diversity index of 1.01 while exclosure had a diversity index of 0.741.

Compactação superficial de Latossolos sob integração lavoura: pecuária de leite no noroeste do Rio Grande do Sul / Surface compaction of oxisols with crops: dairy cattle production in northwest of Rio Grande do Sul, Brazil

Em sistemas de integração lavoura-pecuária, o solo sofre pressões pelo pisoteio animal e tráfego de máquinas, alterando sua estrutura. Neste trabalho, avaliaram-se a densidade, a porosidade e a resistência do solo à penetração em cinco propriedades rurais que adotam o sistema de integração lavoura-pecuária. Os resultados indicaram um aumento da compactação pelo pisoteio animal na camada superficial do solo (0,10m). Os valores de densidade estavam acima de 1,4Mg m-3, a macroporosidade abaixo de 0,10m³ m-3 e a resistência à penetração acima de 2MPa na umidade de 0,26kg kg-1, o que indica degradação física do solo. Assim, é necessário adotar práticas de manejo adequadas para a recuperação desses solos e evitar o aumento da compactação.

In crop and livestock integration system, pressure applied by animal trampling and farm-machinery wheeling changes soil structure. In this study soil bulk density, porosity and soil penetration resistance were evaluated in five farms which adopt the crop and livestock integration system. The results indicated an increase in soil compaction by cattle trampling in the surface soil layer (0.10m). The bulk density was above 1.4Mg m-3, the porosity is below 0,10m³m-3 and soil penetration resistance is above 2MPa at 0.26kg kg-1 soil moisture, which characterize soil physical degradation. Thus, adoption of management practices suitable for the soil physical amelioration and prevent further increase in the state of compaction is necessary.

Effects of human trampling on a rocky shore fauna on the Sao Paulo coast, southeastern Brazil / Impactos do pisoteio humano na fauna de um costão rochoso do litoral de São Paulo, no sudeste brasileiro

Increased tourist activity in coastal regions demands management strategies to reduce impacts on rocky shores. The highly populated coastal areas in southeastern Brazil are an example of degradation caused by development of industry and tourism. Among different shore impacts, trampling has been intensively studied, and may represent a significant source of stress for intertidal fauna. A randomised blocks design was applied to experimentally study the effects of two different trampling intensities on richness, diversity, density and biomass of the rocky shore fauna of Obuseiro beach, Guarujá, southeastern Brazil. Blocks were distributed in two portions of the intertidal zone, dominated respectively by Chthamalus bisinuatus (Cirripedia) and Isognomon bicolor (Bivalvia). Blocks were trampled over three months, simulating the vacation period in Brazil and were monitored for the following nine months. Results indicate that Chthamalus bisinuatus is vulnerable to trampling impacts. Richness, diversity and turn-over index tended to be higher in trampled plots four months after trampling ceased. In general, results agree with previous trampling studies, suggesting that even low intensities of trampling may cause some impact on intertidal communities. Management strategies should include isolation of sensitive areas, construction of boardwalks, visitor education and monitoring programmes. In Brazil, additional data obtained from experimental studies are necessary in order to achieve a better understanding of trampling impacts on rocky shore communities.

O aumento da atividade turística em áreas costeiras nas últimas décadas faz necessária a adoção de estratégias de manejo para reduzir os impactos gerados às comunidades de costões rochosos. A região costeira do sudeste brasileiro possui bons exemplos de degradação causada pelo turismo e desenvolvimento industrial. Dentre os diferentes distúrbios causados pela visitação, o pisoteio têm sido estudado de forma intensa e pode representar uma fonte significativa de impactos para as comunidades da zona entre-marés. Neste projeto, foi aplicado um desenho de blocos randômicos para se avaliar experimentalmente os efeitos de duas intensidades de pisoteio na riqueza, diversidade, densidade, recobrimento e biomassa da fauna de um costão situado na praia do Obuseiro, no município do Guarujá, São Paulo, Brasil. Os blocos foram alocados em dois povoamentos diferentes, dominados respectivamente por Chthamalus bisinuatus (Cirripedia) e Isognomon bicolor (Bivalvia). O pisoteio foi aplicado durante três meses, simulando a temporada de férias no Brasil, e os blocos foram monitorados nos nove meses seguintes. Os resultados indicaram que Chthamalus bisinuatus é vulnerável aos impactos do pisoteio. Os índices de riqueza, diversidade e turnover apresentaram uma tendência ao aumento nas áreas pisoteadas quatro meses após o término do pisoteio. No geral, os resultados concordam com estudos anteriores e sugerem que mesmo baixas intensidades do distúrbio podem causar impacto às comunidades bentônicas. Estratégias de manejo devem envolver o isolamento de áreas sensíveis, a construção de passarelas, a educação dos visitantes e o monitoramento das comunidades impactadas. No Brasil, a realização de maior quantidade de estudos experimentais é necessária para a melhor compreensão dos impactos do pisoteio nas comunidades de costões rochosos.