Ramp tests can be used for the evaluation of bond strength between soils and geosynthetics and between different layers of geosynthetics. This paper presents a theoretical and experimental study on the use of this type of test to measure soil-geosynthetic interface bond strength. Granular and cohesive soils and a wide range of geosynthetic types were employed in the tests. Tests with one to three geosynthetic layers were carried out with measurements of mobilised tensile loads. The results show the factors that may affect test results, such as apparatus size, soil type, geosynthetic tensile stiffness, and surface characteristics. Mechanisms of interface failure and of load transference between different layers are also identified and discussed.

Chemical soil quality is one of the factors more quickly affected by anthropogenic degradation processes and is one of the more important components for the development of agriculture. Thus, this study aimed to evaluate the effects of different doses of cattle manure and rock powder on the chemical characteristics of soil cultivated with butter kale. The treatments were arranged in five randomized blocks in a 4´4 factorial for the different doses of bovine manure (60, 120, 180 and 240 g/plant) combined with doses of rock powder (6, 12, 18 and 24 g/plant). Each block was composed of three plots, 18 m long and 1 m wide. The bed was composed of six portions, and each experimental plot consisted of 14 plants spaced at 0.40´0.40 m. At the end of the experiment, the following were analyzed: pH, organic matter, P, K, Na, Mg, exchangeable acidity, cation exchange capacity (CEC), sum of base and base saturation. The doses of bovine manure and MB-4 provided an increase in pH, organic matter, concentration of phosphorus, potassium, sodium, calcium, magnesium, exchangeable acidity, cation exchange capacity, sum of the base and saturation of the soil base. The doses of 240 g of cattle manure and 24 g of rock dust generated an increase in the chemical properties of the soil.

The supply of organic matter in soil of arid and semiarid in Brazilian regions is very import, as it allows to increase crop yields.  However, there are few studies on alternative sources of fertilizer for vegetables.  Therefore, the objective was to evaluate the effect of different doses of bovine manure and rock powder (RP) on growth characteristics, concentration of chlorophyll, and physiological indices and production of (B. oleracea L. var. acephala).  The treatments were arranged in five randomized blocks in a factorial 4 x 4 reference doses of bovine manure (60, 120, 180 and 240 g pit-1) combined with doses of rock powder (6, 12, 18 and 24 g pit-1).  Doses of bovine manure and rock powder of 180 and 18 g, respectively, increased the growth of B. oleracea by plant height, stem diameter, leaf number.  The combination doses of bovine manure 120 g + 12 g rock powder and 120 g of bovine manure + 18 g rock powder, provided, in this order, larger leaf area results for the productivity of B. oleracea.  The bovine manure promotes greater concentration of CO2, net photosynthesis and stomatal conductance of B. oleracea plant, while rock powder limits these characteristics.  Intermediate doses of bovine manure and RP promote higher growth and yield of B. oleracea.

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