-Several degraded areas can be found along the Highway MG-010 that crosses the Espinhaço Mountain Biosphere Reserve in the Brazilian state of Minas Gerais. Restoration by planting the legume Cajanus cajan was implemented in some of these areas. The present study compares plant species richness, diversity, abundance, equitability, similarity, and soil composition between restored and non-restored areas, in an attempt to evaluate the effectiveness of the use of C. cajan in the restoration process in the mountain environment. Each treatment (restored and non-restored) had four sampling areas, each with three 300 m 2 plots. We counted and identified every individual plant found within these plots. We also collected soil from the superficial layer (0-10 cm) of each sampling area in both treatments. The areas where C. cajan was planted revealed lower species richness, diversity, and plant abundance. The soil of these areas also contained higher levels of Phosphorus and Magnesium. Plant equitability and similarity between plots and other soil components (pH, Nitrogen, Aluminum, Calcium, Potassium, H+Al, sum of bases -SB, cation exchange capacity -CTC, base saturation -V%, aluminum saturation -M%) did not differ between the two treatments. Contrary to the expectations, soil enhancement in the quartzitic soil poor in nutrients in the rupestrian fields can facilitate the invasion by exotic plants, which are not adapted to the lack of nutrients. As it appears, the use of C. cajan in restoration projects represents a mistake and future restoration plans should avoid the use of exotic species, given that they may cause negative effects on the native plant community, as demonstrated here in the rupestrian fields.Keywords: environmental impacts, restoration ecology, Serra do Cipó, tropical mountains.RESUMO -Várias áreas degradadas podem ser encontradas ao longo da rodovia MG-010, que corta a Reserva da Biosfera da Cadeia do Espinhaço, em Minas Gerais, Brasil. Algumas dessas áreas foram restauradas através do plantio da leguminosa Cajanus cajan. O presente trabalho compara a riqueza, diversidade, abundância, equitabilidade e similaridade da comunidade de plantas, e composição do solo de áreas degradadas restauradas e não restauradas, a fim de avaliar a efetividade do uso de C. cajan no processo de restauração. Cada tratamento (áreas restauradas e não-resturadas) teve quatro áreas amostrais, as quais, por sua vez tiveram três parcelas de 300 m 2 . Em cada parcela, todos os indivíduos de planta foram contados e identificados. Além disso, foi coletado o solo da camada superficial em todas as quatro áreas amostrais de ambos os tratamentos. As áreas onde C. cajan foi plantado apresentaram menores riqueza, diversidade e abundância de plantas. O solo dessas áreas também apresentou níveis mais altos de Fósforo e Magnésio. Equitabilidade e similaridade e outros componentes do solo (pH, Nitrogênio, Alumínio, Cálcio, Potássio, H+Al, Soma de Bases -SB, Capacidade de Troca Catiônica-CTC, Saturação de Bases -V%, Saturação de Alumíni...

The phytophysiognomies of the Neotropical savannah occur at different altitudes, which can determine distinctions in the levels of light and shade that plants are exposed. The focus of the study is analysing the functional traits of the leaves of Byrsonima verbascifolia (L.) Rich., Roupala montana Aubl. and Solanum lycocarpum A. St.-Hil. growing in phytophysiognomies at two distinct altitudes. We evaluated leaf anatomy, the quantum yield of photosystem II, and the photosynthetic pigments in plants occurring at two areas of Campo sujo, which are separated by 700 m of altitude, during the rainy season. The three plant species occurring at higher altitudes had thicker adaxial epidermis. B. verbascifolia and S. lycocarpum occurring at higher altitudes had thicker palisade parenchyma, whereas only B. verbascifolia had thicker spongy parenchyma at the same site. The quantum yield of photosystem II, and photosynthetic pigments had little differences between plants occurring at higher and lower altitudes. The results analysed show high structural modifications and low physiological alterations from altitudinal conditions. Thus, the influence of the abiotic factors appears to modulate the plastic responses of plants across altitude.

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Plants respond to variation in luminosity leading to the existence of distinct leaf traits in plants that inhabit the understory, edge, and canopy of tropical forests. In the present work, the long-life leaves of Ouratea castaneifolia Engl. (Ochnaceae) in forest edge and understory were evaluated. Leaves of 20 individuals were collected from each habitat. Median regions of leaves from the third node were fixed in FAA. Freehand-cut transverse sections were stained in astra blue and safranin. The thickness of tissues, leaf area, specific leaf mass, and relative water content were quantified. Quantum yield of photosynthesis was measured by Fv/Fm, and instantaneous light response curves were performed to extract ETR max , PAR sat , and DF/Fm 0 sat. Quantification of photosynthetic pigments was also performed. Leaf area was lower at the forest edge, while the specific leaf mass was higher. No structural differences or differences in relative water content were observed between individuals of the two environments. The thicknesses of the cuticle on the adaxial surface, the epidermal cells on the abaxial surface, and the palisade and spongy parenchyma were greater in individuals at the forest edge. The values of Fv/ Fm were around 0.8 in the predawn. In midday, higher values of Fv/Fm were observed in individuals located in the understory. Individuals of the understory had higher levels of chlorophyll a, chlorophyll b, and total chlorophyll. The morphological traits were the most plastic, but modulations in both morphology and pigment concentration may explain the maintenance of a similar predawn quantum yield between environments.

Ecophysiological responses of plants are useful for monitoring the success of ecological restoration projects that target species conservation. In this study we evaluated the ecophysiological traits of individuals of Chamaecrista semaphora from a natural population and from a site under restoration. Water potential and chlorophyll a fluorescence parameters were measured both in adult and young plants of the two populations. No difference in water potential was found between sites, but individuals in the restored site had higher water potential at predawn. Adults in the natural site presented lower daily values of potential quantum yield, indicating the occurrence of photoinhibition. Individuals in the restored site also presented higher maximum relative electron transport rate (ETR MAX ). No difference was found in leaf carbon isotope discrimination values ( 13 C) between plants growing in restored and natural sites, suggesting similar water use efficiency. These results indicate that C. semaphora individuals in the restored site had similar or better photosynthetic and water economy performances than individuals at the natural site. Methodologies traditionally employed to assess stress response of plants, such as chlorophyll a fluorescence and procedures used to evaluate the efficiency of water use, allowed us to verify the success of restoration procedures using an endangered species.

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Rupestrian fields are located above 900 m of altitude and have many endangered plants. They may present patches of Campo sujo (shrub savannah), which is a phytophysiognomy commonly found in Neotropical savannah at lower altitudes. Based on the atypical occurrence of the Campo sujo area were studied the morphological and physiological responses of three plant species in two altitudinal levels. Morphology parameters, stomatal conductance, and water potential were evaluated in leaves at rainy season. Environmental conditions and physiology were taken along specific days. High-altitude area presented lower temperatures and higher air relative humidity during the day than low-altitude area. Distinct and uneven responses in the production of stomata and the caliber of the sieve and tracheal elements among plants in the two areas were observed. Stomatal conductance was normally lower than high altitude. Water potential at high altitude was lower at predawn, similar at noon, and higher at the end of the daylight. We observed different strategies among the three species, without clear anatomy pattern. The lower stomatal conductance rates at high altitude that do not follow the pattern expected for the humidity levels are found, which may be the result of strong and frequent winds and low temperature. Water potential recovery may reflect higher air humidity observed on this site.

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