Aerial and root morphophysiological aspects of Eucalyptus and Corymbia species with different water deficit tolerances

A maioria das plantações comerciais florestais no Brasil é composta por espécies e híbridos de Eucalyptus e Corymbia que têm se expandido para regiões com diferentes características de regime pluviométrico, temperatura e sazonalidade climática. O déficit hídrico (DH) é um dos principais fatores que limitam o crescimento e a produção das espécies. O objetivo desse estudo foi avaliar os aspectos morfológicos e fisiológicos da copa e do sistema radicular, bem como produção de folhedo e distribuição de nutrientes na planta, de espécies de Eucalyptus e Corymbia com diferentes tolerâncias ao déficit hídrico. Este estudo foi conduzido na Estação Experimental de Ciências Florestais de Itatinga - SP, Esalq-USP. O experimento possui seis tratamentos, cada um composto por uma espécie com um nível de tolerância hídrica (E. grandis e E. urophylla, baixa tolerância; E. cloeziana e C. citriodora, tolerância intermediária; E. camaldulensis e E. brassiana, alta tolerância). Para cada espécies foi instalada uma parcela experimental, lado a lado, sob um mesmo extrato climático (Cwa) e tipo de solo (Latossolo Vermelho-Amarelo distrófico típico de textura média). No primeiro capítulo foi avaliada a produtividade e alguns aspectos morfisiológicos da copa das espécies. Quanto maior a tolerância ao déficit hídrico, menor o crescimento volumétrico e de massa da espécie. Entretanto, espécies mais tolerantes possuem menor área e índice de foliar, densidade estomática e potencial hídrico foliar. No segundo capítulo foi avaliado o sistema radicular das espécies. Independentemente da espécie, houve predominância de raízes finas na camada de 0-30 cm do solo e, ao mesmo tempo, diminuição do sistemas radicular com o aumento da idade. O E. camaldulensis apresentou maior comprimento radicular acumulado, enquanto o E. brassiana obteve maior comprimento e área radicular específica no perfil do solo. Espécies com baixa e intermediária tolerância ao DH apresentaram raiz pivotante com maior e menor ramificações laterais. Espécies mais tolerantes ao DH apresentaram várias raízes grossas e média verticalizadas sem raiz pivotante definida. Finalmente, procurou-se investigar a produção sazonal de folhedo e distribuição de nutrientes nas espécies (terceiro capítulo). Foi observado que no período chuvoso as espécies mais tolerantes ao déficit hídrico, C. citriodora, E. camaldulensis e E. brassiana, apresentaram maior teor de B no folhedo. Essas espécies demonstraram maiores teores de N, Ca, Cu e Zn e menor teor de S na raiz e menor estoque de N e P na folha. O E. camaldulensis teve maior estoque de K nas folhas e raiz, e mais Ca na casca no primeiro ano pós-plantio.The majority of commercial forest plantations in Brazil are composed of Eucalyptus and Corymbia species and its hybrids that spans for regions with different rainfall, temperature and climatic seasonality. Water deficit may limit tree growth and yield. This study aimed to evaluate aerial and root morphophysiological aspects, as well as leaf production and distribution of nutrients in the plant, for Eucalyptus and Corymbia species with different water deficit tolerances (E. grandis and E. urophylla, low tolerance; E. cloeziana and C. citriodora, intermediate tolerance; E. camaldulensis and E. brassiana, high tolarance). The experiment was located at Itatinga Forest Science Experimental Station, Itatinga-SP, Brazil. There was one experimental plot for specie, side by side, under the same climate (Cwa) and soil (typical dystrophic Red-Yellow Latosol with medium texture). In the first chapter, productivity and some morphophysiological aspects of species were evaluated. The greater the tolerance to water deficit, the lower the volumetric and mass growth for all species. However, more tolerant species had less leaf area, leaf area index, stomatal density and leaf water potential. In the second chapter, the root system of the species was assessed. Regardless of the species, fine root predominates in the 0-30 cm soil layer and, at the same time, as the trees aged, tree root systems decreases. E. camaldulensis had higher accumulated root length in the soil profile, while E. brassiana has higher length and specific root area. Species with low and intermediate tolerance to water deficit had a taproot well defined with more and less lateral root ramifications. Species more tolerant to water deficit had several thick and medium vertical roots without a defined taproot. Finally, in the third chapter, seasonal production of leaf litter and distribution of nutrients in the species was investigated. It was observed that in the rainy season, species more tolerant to water deficit, C. citriodora, E. camaldulensis and E. brassiana, had a higher leaf B content. These species showed higher levels of N, Ca, Cu and Zn and lower content of S in roots and lower N and P stock in leaves. E. camaldulensis had a higher K stock in the leaves and roots, and more Ca in the bark after first year

Relevance of strategic environmental assessment to Rio Grande basin management

This research aims to identify the vulnerabilities of Rio Grande basin in Minas Gerais state as well as to investigate, through technical, legal, social, and governmental aspects, the relevance of SEA as an environmental tool for the conservation and preservation of watersheds. Rio Grande basin evaluation was performed by using this following database: soil classes, land use classification, water quality index, and economic ecological index. It was performed multi-criteria decision analysis based on analytic hierarchy process methodology. 52.5% of the studied area was classified as “good” preservation condition. Alto Grande (GD1), Mortes/Jacaré (GD2) and Furnas (GD3) units did not contain significant percentages of their areas corresponding to the preservation class “very good”. In the studied area, 34.51% was classified as “medium” preservation condition, thus indicating the need for effective measures for the river basin conservation. These findings highlight the potential importance of including the SEA in the decision-making process for plans, policies and programs related to the integrated management of water resources

AGROFORESTRY AS A SUSTAINABLE ALTERNATIVE FOR ENVIRONMENTAL REGULARIZATION OF RURAL CONSOLIDATED OCCUPATIONS

The great expectation about the New Forest Code consisted in reducing the hermeneutics distortions and increasing legal certainty for farmers. However, the new legislation raised more uncertainties and discussions, mainly because it consolidates the anthropic use and allows of low-impact activities in areas that should, by law, be kept untouched. This study aimed to survey and to describe the legislation related to protected areas on the rural area (APP and RL), to analyze the consolidated forms of use, occupation and low impact activities that can be developed in these areas, and to propose sustainable technical alternatives for interventions in the areas already consolidated and their recovery. The text is based on literature and documents, elaborated on the survey and study of legal aspects about protected areas in rural properties of Brazil and the main low-impact farming techniques, highlighting the agroforestry systems as an alternative of consolidated occupations in environmental protection areas. The text provides in an organized way the main aspects of the legislation on such areas and describes the sustainable activities allowed in APP and RL according to the flexibility of the new Forest Code

Resumos em andamento - Saúde Coletiva

Resumos em andamento - Saúde Coletiv

Resumos em andamento - Saúde Coletiva

Resumos em andamento - Saúde Coletiv