Influence of physical and chemical properties of different soil types on optimal soil moisture for tillage

Plastičnost je tla područje konzistencije tla, odnosno predstavlja promjenu stanja tla zbog različite vlažnosti tla djelovanjem vanjskih sila. Konzistencija određuje veličinu otpora koje tlo pruža pri obradi, stoga je cilj istraživanja utvrditi optimalno stanje vlažnosti tla za obradu te utjecaj fizikalnih i kemijskih svojstva oraničnih horizonata na plastičnost tla, kao jednog od svojstava konzistencije. Istraživanje je provedeno na tri različita tipa tla: aluvijalnome, lesiviranome te na ritskoj crnici. Utvrđene su statistički značajne razlike između svih istraživanih tipova tala i to za sadržaj čestica gline, gustoću pakiranja, aktualnu i supstitucijsku kiselost, kationski izmjenjivački kapacitet tla te sadržaj kalcija. Također, utvrđene su statistički značajne razlike između istraživanih tipova tala za donju granicu plastičnosti, gornju granicu plastičnosti te indeks plastičnosti. Prosječna utvrđena vrijednost donje granice plastičnosti, kao važnog elementa za određivanje optimalnoga trenutka obrade tla, iznosila je 18,9% mas. na aluvijalnome tlu, 24,0% mas. na lesiviranome tlu, dok je na ritskoj crnici iznosila 28,6% mas. Vrlo značajnu korelaciju pozitivnoga smjera s granicama plastičnosti pokazali su humus, glina, KIK, sitni prah, magnezij, natrij i kalcij, dok su vrlo značajnu korelaciju, ali negativnoga smjera, pokazali hidrolitička kiselost, krupni pijesak, sitni pijesak i krupni prah. Kreiranim regresijskim modelima može se procijeniti optimalno stanje vlažnosti tla za obradu na temelju osnovnih svojstava tala. Preciznost modela značajno se povećava uvođenjem većega broja fizikalnih i kemijskih svojstva tla, a dopunsku preciznost modela mogu povećati podatci o tipu tla.Soil plasticity is the area of soil consistency, i.e. it represents a change in soil condition due to different soil moisture influenced by external forces activity. Consistency determines soil resistance in tillage, therefore, the aim of the research was to determine the optimum soil moisture condition for tillage and the influence of the chemical and physical properties of the arable land horizons on the soil plasticity on three different types of soil (fluvisol, luvisol and humic glaysol). Statistically significant differences were found between all examined soil types, such as the content of clay particles, the density of packaging and the actual and substitution acidity, the cation exchange capacity and the content of calcium. There were also statistically significant differences between the examined types of soil for the plasticity limit, liquid limit and the plasticity index. The average established value of plasticity limit as an important element for determining the optimal moment of soil tillage was 18.9% mass on fluvisol, 24.0% mass on luvisol and 28.6% mass on humic glaysol. Very significant positive direction correlation with plasticity limits was shown by organic matter, clay, fine silt, magnesium, sodium and calcium, while very significant negative direction correlation was shown by hydrolytic acidity, coarse sand, fine sand and coarse silt. Created regression models can estimate the optimal soil moisture condition for soil cultivation based on the basic soil properties. The model precision is significantly increased by introducing a greater number of agrochemical and agrophysical soil properties, and the additional precision of the model can be increased by soil type data

Influence of physical and chemical properties of different soil types on optimal soil moisture for tillage

Plastičnost je tla područje konzistencije tla, odnosno predstavlja promjenu stanja tla zbog različite vlažnosti tla djelovanjem vanjskih sila. Konzistencija određuje veličinu otpora koje tlo pruža pri obradi, stoga je cilj istraživanja utvrditi optimalno stanje vlažnosti tla za obradu te utjecaj fizikalnih i kemijskih svojstva oraničnih horizonata na plastičnost tla, kao jednog od svojstava konzistencije. Istraživanje je provedeno na tri različita tipa tla: aluvijalnome, lesiviranome te na ritskoj crnici. Utvrđene su statistički značajne razlike između svih istraživanih tipova tala i to za sadržaj čestica gline, gustoću pakiranja, aktualnu i supstitucijsku kiselost, kationski izmjenjivački kapacitet tla te sadržaj kalcija. Također, utvrđene su statistički značajne razlike između istraživanih tipova tala za donju granicu plastičnosti, gornju granicu plastičnosti te indeks plastičnosti. Prosječna utvrđena vrijednost donje granice plastičnosti, kao važnog elementa za određivanje optimalnoga trenutka obrade tla, iznosila je 18,9% mas. na aluvijalnome tlu, 24,0% mas. na lesiviranome tlu, dok je na ritskoj crnici iznosila 28,6% mas. Vrlo značajnu korelaciju pozitivnoga smjera s granicama plastičnosti pokazali su humus, glina, KIK, sitni prah, magnezij, natrij i kalcij, dok su vrlo značajnu korelaciju, ali negativnoga smjera, pokazali hidrolitička kiselost, krupni pijesak, sitni pijesak i krupni prah. Kreiranim regresijskim modelima može se procijeniti optimalno stanje vlažnosti tla za obradu na temelju osnovnih svojstava tala. Preciznost modela značajno se povećava uvođenjem većega broja fizikalnih i kemijskih svojstva tla, a dopunsku preciznost modela mogu povećati podatci o tipu tla.Soil plasticity is the area of soil consistency, i.e. it represents a change in soil condition due to different soil moisture influenced by external forces activity. Consistency determines soil resistance in tillage, therefore, the aim of the research was to determine the optimum soil moisture condition for tillage and the influence of the chemical and physical properties of the arable land horizons on the soil plasticity on three different types of soil (fluvisol, luvisol and humic glaysol). Statistically significant differences were found between all examined soil types, such as the content of clay particles, the density of packaging and the actual and substitution acidity, the cation exchange capacity and the content of calcium. There were also statistically significant differences between the examined types of soil for the plasticity limit, liquid limit and the plasticity index. The average established value of plasticity limit as an important element for determining the optimal moment of soil tillage was 18.9% mass on fluvisol, 24.0% mass on luvisol and 28.6% mass on humic glaysol. Very significant positive direction correlation with plasticity limits was shown by organic matter, clay, fine silt, magnesium, sodium and calcium, while very significant negative direction correlation was shown by hydrolytic acidity, coarse sand, fine sand and coarse silt. Created regression models can estimate the optimal soil moisture condition for soil cultivation based on the basic soil properties. The model precision is significantly increased by introducing a greater number of agrochemical and agrophysical soil properties, and the additional precision of the model can be increased by soil type data

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Influence of physical and chemical properties of different soil types on optimal soil moisture for tillage

Soil plasticity is the area of soil consistency, i.e. it represents a change in soil condition due to different soil moisture influenced by external forces activity. Consistency determines soil resistance in tillage, therefore, the aim of the research was to determine the optimum soil moisture condition for tillage and the influence of the chemical and physical properties of the arable land horizons on the soil plasticity on three different types of soil (fluvisol, luvisol and humic glaysol). Statistically significant differences were found between all examined soil types, such as the content of clay particles, the density of packaging and the actual and substitution acidity, the cation exchange capacity and the content of calcium. There were also statistically significant differences between the examined types of soil for the plasticity limit, liquid limit and the plasticity index. The average established value of plasticity limit as an important element for determining the optimal moment of soil tillage was 18.9% mass on fluvisol, 24.0% mass on luvisol and 28.6% mass on humic glaysol. Very significant positive direction correlation with plasticity limits was shown by organic matter, clay, fine silt, magnesium, sodium and calcium, while very significant negative direction correlation was shown by hydrolytic acidity, coarse sand, fine sand and coarse silt. Created regression models can estimate the optimal soil moisture condition for soil cultivation based on the basic soil properties. The model precision is significantly increased by introducing a greater number of agrochemical and agrophysical soil properties, and the additional precision of the model can be increased by soil type data