RESUMOA aplicação de P no solo pode afetar a disponibilidade de Zn para as plantas, dependendo de sua localização. Com o objetivo de avaliar a resposta de milho à adição de Zn no solo e determinar seu nível crítico no solo e na planta, em relação à localização de P, em amostras de dois solos de Minas Gerais, realizou-se um ensaio em casa de vegetação. O experimento consistiu em um arranjo fatorial (2 x 3 x 6), correspondendo a dois solos (Latossolo Vermelho Amarelo variação Una e Argissolo Vermelho Amarelo, doravante denominados LU e PVA, respectivamente); três modos de localização de P (5, 10 e 30% do volume total do solo na dose de 200 mg dm -3 ) e seis doses de Zn (0, 1, 2, 4, 6 e 8 mg dm -3 ). Determinaramse a produção de matéria seca e os teores de Zn na parte aérea das plantas de milho. A adição de Zn aumentou linearmente (p < 0,01) o teor do elemento no solo e a absorção pela planta. No solo LU os níveis críticos variaram de 0,91 a 2,13 mg dm -3 de Zn pelo extrator Mehlich-1 e, na planta, de 18,0 a 24,6 mg kg -1 . Esses níveis foram maiores quando as aplicações de P foram localizadas em menor volume de solo. A localização de P afetou o teor de Zn na Planta. No solo LU, quando o P foi localizado no menor volume de solo e na ausência de Zn, as plantas de milho apresentaram elevados teores de P.Palavras-chave: nível crítico de Zn, forma de aplicação de P, interação Zn/P Availability of zinc to corn in response to liming and added phosphorus placement in soil ABSTRACT The soil P application can affect Zn availability to plants, depending on the application. The objective of this study was to evaluate corn (Zea mays L.) response to zinc (Zn) addition to the soil and to determine its critical level in the soil and in the plant, in relation to added phosphorus (P) placement, using two soil samples from Minas Gerais, Brazil, in a greenhouse experiment. The experiment was conducted in a factorial arrangement (2 x 3 x 6), with two soils [Red Yellow Latosol of the Una Variation (Oxisol) and RedYellow Podzolic (Ultisol), named LU and PVA, respectively]; three forms of added P placement (5, 10 and 30% of the total volume of soil in a dosage of 200 mg dm -3 ), and six Zn dosages (0, 1, 2, 4, 6 and 8 mg dm -3 ). The dry matter production and the contents of Zn in the aerial part of the corn plants were determined. The addition of Zn linearly increased (p < 0.01) its content in the soil and plant uptake. The critical levels for the LU soil ranged from 0.91 to 2.13 mg dm -3 of Zn as determined by the Mehlich-1 extractor and plant levels ranged from 18.0 to 24.6 mg kg -1 . These levels were higher when P was placed in smaller soil volumes. P placement affected the Zn content in the plant. In LU soil, when P was placed at the smallest soil volume and Zn privation, the corn plants presented elevated P levels.

Three growing systems of Arabica coffee were evaluated under the energy perspective, in the state of Espírito Santo in Brazil. The systems are conventional cultivation (CC), cultivation with good agricultural practices (CGP) and organic farming (OF). It was made a comparison of the energy flows within these three systems to show sustainable levels of each one based on production average data of several family-farming units. Therefore, we analyzed crop yield, total energy efficiency reverse (TEER), energy efficiency of ripe coffee (EERC) and nonrenewable energy efficiency (NREE). OF system had values for TEER, EERC and NREE of 3.3 4.7 and 7.9 respectively. Yet CC showed values of 1.8, 1.9 and 1.6 for TEER, EERC and NREE respectively. Furthermore, CGP presented values for TEER, EERC and NREE of 0.7, 1.3 and 1.4 respectively. The highest yield was observed in CGP, reaching an amount of 1794 kg ha -1 (17,455 MJ); however, this system expends more energy than it converts. Thus, over those points, OF is the most sustainable system.

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Appropriate techniques for cultivation in highland regions are recommended within the planning of coffee crop based on agroecological zoning. To establish sustainable production systems combining economic viability, social welfare and environmental protection is the great challenge. The geographical area of the Denomination of Origin 'Mountains of Espírito Santo' is composed of sixteen municipalities, totaling 8,438.20 km². Coffee plantations are located on sloping ground between 500 m and 1,200 m with increased use of rust-tolerant/resistant coffee cultivars that are adapted, productive and have good cup quality. Conservationist practices are used to increase the water reservoir in the soil. Two main types of processing are used in post-harvest: natural and wet. Altitude has been identified as the most relevant geographical attribute for sensory quality in this region. Coffee grades ranging from 76.38 to 95.13 points have being found. Pulped coffees have flavors of cane molasses, red fruits, caramel, chocolate, spices, floral, vanilla, citric acidity, shiny, liqueur, velvety, intense and medium body. Natural coffees present flavors of wine, yellow fruits, caramel, chocolate, dulce de leche, spices, honey, lemon balm, pepper, almond, citric acid, bright, liqueur, intense and medium body. The Geographic Indication (GI) of the 'Mountain coffee of Espírito Santo' will contribute to the expression of attributes related to culture, traditions, identities, food security, social differences, and standardization of coffee quality given the peculiarities found in the diversity of ecosystems. This will provide worldwide recognition as a region for the production of a diversity of special and sustainable coffees. It will lead the region towards the socioeconomic sustainability of the population based on ecological coffee farming.