User manual HANNA INSTRUMENTS HI 3896

[. . . ] 14 Health & Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . · Nitrogen (NO3) test Use the pipette to transfer 2. 5 ml of the clear general soil extract to a clean test tube. To avoid agitation of the soil, squeeze the bulb of the pipette before inserting it into the soil extract solution. ] Add the content of one packet of HI3896-N reagent. Replace the cap and shake vigorously for 30 seconds to dissolve the reagent. [. . . ] If, for example, we have a soil with 37% clay, 38% sand and 25% silt, the soil is classified as "clay loam" (Fig. Types of soil in relation to the texture Peach Pear (data ESAV) SOIL ANALYSIS The soil analysis is very useful, in order to plan fertilization and to know the residues of fertilizers in relation to the crop, tillage and climate. An analysis can highlight shortages and help the understanding of the causes of an abnormal growth. Testing the soil during the crop cycle and comparing the results with the plant growth can be an useful experiment for the next cultivation. 1) Extracting Soil Sample ­ With a large field, take 1 or 2 samples per 1000 m2 (0. 25 acre) of homogeneous areas. ­ Even for smaller areas, 2 samples are recommended (the more the samples, the better the end-results, because the sample is more representative) ­ For a small garden or plot, 1 sample is sufficient 2) Avoid extracting samples from soil presenting obvious anomalies 3) Sample quantity: Take the same quantity of soil for each sample. For example, use bags with similar dimensions (1 bag per sample) 13 Sampling Among different types of soil, the loam soil is considered as being suitable for crop growth. However, other types of soil, with a rational management, can also provide positive results. The soil texture is the cause of important aspects such as porosity, tenacity, adhesivity and plasticity. 4 Tab. 7. CROP Asparagus SOIL CONTENT very low low medium medium-high high very high very low low medium medium-high high very high very low low medium medium-high high very high very low low medium medium-high high very high very low low medium medium-high high very high very low low medium medium-high high very high very low low medium medium-high high very high very low low medium medium-high high very high ADVISED DOSES (kg/ha) N P2O5 K2O 160 120 100 90 80 70 140 110 90 80 70 60 340 300 280 260 240 220 300 270 240 230 210 200 0 0 0 0 0 0 160 120 100 90 80 70 150 130 110 90 80 70 180 160 150 140 130 120 120 100 70 50 40 20 130 90 70 50 40 30 200 150 120 90 60 40 200 150 120 90 60 40 150 130 100 80 60 40 150 130 100 80 60 40 250 180 150 120 90 60 150 100 80 60 50 40 180 150 130 110 90 80 170 120 80 60 50 40 230 150 120 90 60 46 230 150 120 90 60 40 220 170 130 100 80 60 230 180 150 120 90 60 250 200 150 120 90 60 170 120 80 60 50 40 Barley Corn silage Maize Porosity is important for the exchange of gases and liquids. Micro-porosity (porous < 2 10 µm) permits water to be retained while macro-porosity (porous > 10 µm) contributes to a fast circulation of air and water. Plants therefore are in need of a correct relationship between micro and macro porosity. Clay soils have a greater micro-porosity than sandy soils and hence hold more water and remain wet for a longer period. Because of the greater tenacity and adhesivity of clay soils, they are called heavy while sandy soils are referred to as light. Organic matter, caused by animal and vegetable residues, is another important constituent of the solid part of the soil. Organic matter has a positive effect on the soil fertility by adding nutrients, stabilizing the pH reaction and permitting a good retainment of water. Organic matter is also important for the activity of microorganisms and, in general, contributes towards prevention of soil erosion. The colloidal portion, composed of micro-particles (1-100 µm), is important for holding nutrients. Since most of these particles have a negative charge, the colloidal portion has a particularly large capacity to retain cations (NH+, K+, Na+, Ca++, Mg++, etc. ). The CEC 4 (Cation Exchange Capacity) is higher in soils rich with clay and organic matter than in sandy soils. Soybean CHEMICAL COMPOSITION The chemical composition of soil includes pH and chemical elements. Their analysis is necessary for better management of fertilization, tillage and in order to choose the most suitable plants for best results. By using the HANNA Soiltest, it is possible to measure pH and the most important elements for plant growth, that is, nitrogen (N), phosphorus (P) and potassium (K). [. . . ] It contributes to the formation of buds, roots and blooming as well as lignification. A lack of phosphorus results in: stifling of plant, slow growth, a reduction of production, smaller fruits and a lower expansion of the roots. Most of the Phosphorus present in the soil is not available for plants and its release in the soil solution from which it is taken, is very slow. Therefore, in order to avoid an impoverishment of the soil, and to give to the plants the appropriate quantity, a rational fertilization is needed. [. . . ]