WARNA TANAH

1. WARNA TANAH

2. Soil Color Munsell Notation Hue Value Chroma

3. Munsell Notation Value (amount of black or white added to the color Hue (position on the color wheel) Chroma (amount of brightness of saturation of the color

4. WARNA TANAH • Color of soils tells us much about some of its other properties. • The color of a surface soil horizon depends mainly on its organic matter content – the darker the soil, the more organic matter it contains. This organic matter imparts favorable properties to the soil, such as better aggregation and a high water-holding capacity. Also, dark soils absorb more radiation during the day, and radiate more heat during the night. • In subsoil horizons, soil color indicates the wetness and aeration conditions of the soil. • In general, reddish and brownish subsoils indicate good aeration and little water logging (you see the iron red) • Grayish and olive colors indicate much water logging and a chemical reduction of iron. • A mottled subsoil, one with a splotchy pattern of brownish and grayish colors, is indicative of a fluctuating ground water table.

5. Munsell Color System • Mendefinisikanwarnatanahdnegan parameter: Hue, Value danChroma. • Huediartikansebagaiwarnaaktual, sepertiMerah, Biru, Hijau, dst. • Valuediartikansebagai “keterangan” atau “kegelapan” warna. • Chromadiartikansebagaikekuatanataukelemahansuatuwarna. Soil scientists use the Munsell Color book to determine the color of the soil to help determine in what type of soil it is along with using texture.

6. DESKRIPSI WARNA TANAH 1. Take a ped of soil from each horizon and note on the data sheet whether it is moist, dry or wet. If it is dry, moisten it slightly with water from your water bottle. 3. Break the ped and compare the color of the inside surface with the soil color chart. 2. Stand with the sun over your shoulder so that sunlight shines on the color chart and the soil sample you are examining. Note: Sometimes, a soil sample may have more than one color. Record a maximum of two colors if necessary, and indicate (1) the Main (dominant color) and (2) the Other (sub-dominant color).

7. Soils can vary greatly in color depending on the soil forming factors and other conditions. The soil lets water move through slowly and tends to be wet and low in oxygen (reduced) The soil lets water move through easily and tends to be well drained and high in oxygen (oxygen)

8. WARNA TANAH • Secara langsung mempengaruhi penyerapan sinar matahari dan salah satu faktor penentu suhu tanah. • Secara tidak langsung berhubungan dengan sifat-sifat tanah, misal informasi subsoil drainase, kandungan bahan organik surface horizon, pembeda antar horison. • Diukurmenggunakanstandarwarna (Soil MunsellColor Chart) . • KeteranganSoil MunsellColor Chart : “ The munsell notation identifies color by use of three variables: hue, value, and chroma . • Hue is the dominantspectra – color, that is, whether the hue is a pure color such as yellow, red, green, or a mixture of pure color, such as yellow-red. Mixture are identified numerically according to the amount of yellow or red used to produce the mixture. 5YR is an equal of red and yellow. • As the number increases, the amount of the first color (yellow) increases and second color (red) decreases. Value and Chroma are terms that refer to how the hue is modified by the addition of gray. • Value is the degree of lightness or brightness of the huereflected uin the property of the gray color that is being added to the hue. A particular value (gray) is made by mixing a pure white pigment (10) with a pure black pigment (0). If equal amounts of white and black pigment are mixed, the value is aqual to 5. • Chromais the amount of gray of a particular value that is mixed with the pure hue to obstain the actual soil color. A chroma of 1 would be made by adding 1 units of pure hue to a certain amounts of gray; a chroma of 5 would contain 5 units of pure hue to the amount of gray. The lower the chroma, the closer the color is to the pure gray of that value.”

9. WARNA TANAH • Interpretasi : Warna tanah disebabkan oleh adanya bahan organik, dan atau status oksidasi senyawa besi dalam tanah. • Tanah yang dibentuk oleh bahan induk basalt sering berwarna sangat gelap jika tanah tersebut mengandung sedikit atau tidak ada bahan organik • Status oksidasi besi terutama di lapisan bawah: tanah yang aerasi dan drainase bagus, senyawa besi berada dalam bentuk oksidasi (ferri/ Fe3+ ) dan memberikan warna merah atau kuning; tanah yang aerasi dan drainase jelek, senyawa besi tereduksi dalam bentuk ferro (Fe2+) akan memberikan warna abu-abu (gray)

10. Hubungan antara warna tanah dengan kandungan bahan organik di Illinois, USA