549 research outputs found
Curvas de titulação e capacidade tampão dos solos do estado de São Paulo: I - solos sôbre o arqueano, devoniano e glacial
Caracterização de um solo da provincia de Mendes, Cantão Sella, Tarija - Bolivia
No presente trabalho os autores estudam um solo representativo da Província Mendez, Cantão Sella, da região sul da Bolivia. São analisadas as informações disponíveis sobre o clima, geologia, relevo e uso agrícola dessa terra. Foram obtidos resultados morfológlcos e analíticos do solo e com base nestas informações foi elaborada a classificação do solo ao nível de família. O solo apresentou epipedon ócrico, horizonte argílico, carbonatos antigênicos caracterizando um horizonte cálcico e um horizonte petrocálcico subjacente. A classe de tamanho das partículas, a natureza mineralógica e a classe de temperatura, permitiram classificar o solo como: Ordem: Aridisol Subordem: Argid Grande grupo: Paleargid Sub grupo: Petrocalcic Ustalfic Paleargid Família: fine-loamy, mixed, thermic.This paper deals about a representative soil from Província Mendez, Cantão Sella, of the southern region of Bolivia. The climatic, geologic, reliev and land use informations of that soil were studied. Based on the morphological and analytical data obtained, the presence of ochric epipedon, argillic horizon, authigenic lime or calcic horizon, petrocalcic horizon, and considering the particle size mineralogy and the soil temperature classes the following classification was obtained: Order: Aridisol Sub Order: Argid Great Group: Paleargid Sub group: Petrocalcic Ustalfic Paleargid Family: fine-loamy, mixed, thermic
As tortas de cacau e de algodão na adubação da cana
This paper deals with a field trial executed to compare cotton seed and cacau meals in the fertilization of sugar cane, variety Co290. The design chosen was a latin square of 6 x 6. The following conclusions can be drawn: 1. Cottonseed meal revealed to be statistically superior to cacau meal, being even superior to the mineral fertilizers plus cacau meal treatment. 2. From an economical point of view cotton seed meal, as a fertilizer for sugar cane, can not be substituted by cacau meal
Experiências de adubação mineral e orgânica com Capim Kikuyu (Pennisetum clandestinum Hochst.)
Kikuio grass (Pennisetum clandestinum Hochst) is beyond any doubt, a pasture very important for farm animals; since its chemical composition is very similar to that of alfalfa, the present field trial was carried out; a randomized block design with 8 treatments was selected as follows: 1 N - P - K - Ca - Mg (complete manuring) 2 N - P - K - Ca----- (without Mg) 3 N - P - K-------Mg (without Ca) 4 ----P - K - Ca - Mg (without N) 5 N------K - Ca Mg (without P) 6 N - P - Ca - Mg (without K) 7 organic matter (without mineral fertilizers) 8 control Nitrogen was applied as NaN03 (topdressed) and as ammonium sulfate; P2O5 was given as superphosphate associated to bonemeal; K2O was applied as muriate, CaO as "sambaquis" (oyster shells); MgO was given as MgSO4 (topdressed). The source of organic matter was farmyard manure. As far yields are concerned the following observations were made: 1. treatment n. 7 was superior to all others; 2. considering the mineral fertilizers, good responses were due to N and P2O5; 3. the control yield was exceedingly poor, being inferior to all the others treatments; The chemical analyses revealed that: 1. the protein content decreased accordingly to this order: 7, 6, 5 and 1; treatment 4 (without N) gave the lowest protein content; 2. treatment n. 4 produced the highest fat content; treatment no. 7 ranked second; no. 8 gave the lowest fat content; 3. crude fiber: highest - treatment 7; lowest - 8; 4. ashes: the ashes content was higher in treatment 5; proprobably because the most abundant element in the ashes is K, the ash content of treatment 6 (no K) was very low; 5. non nitrogenous substances (determined by difference) - high in treatment 8 and low in treatment 7; 6. mineral elements in the ashes - the element omitted from a given treatment was very low in the grasses therein obtained; this shows the relative poverty of the soil in that element. As general remark the Authors suggest the use of farmyard manure in the fertilization of Kikuio grass; farmyard manure could probably substitute wither green manure or compost
Número de amostras simples de solo para avaliação da fertilidade em alguns ecossistemas amazônicos.
A analise dos solos das areas de mata, mata recem queimada e pastagem de Brachiaria humidicola teve por finalidade determinar o numero minimo de amostras de solo necessarias para perfazer uma amostra composta, que seja representativa para fins de analise da fertilidade do solo. As areas amostradas acham-se estabelecidas em Latossolo Amarelo muito argiloso e com relevo suave-ondulado. Os resultados mostraram ser necessario coletar, na profundidade de 0cm-20cm seis, sub-amostras para areas de mata, 64 para areas de mata recem queimada e 43 para areas de pastagens para obtencao de uma amostra composta representativa a um nivel de 95% de probabilidade estatistica.bitstream/item/75885/1/CPAA-BOL.-PESQ.-4-84.pd
- …