Impact of Compost Application Rate on Lettuce Plant Growth and Soil Agrochemical Status

One way to reduce environmental stress and safeguard soil fertility and ecological sustainability in crop production is by adding compost to the soil substrate. Supplying the soil with organic matter improves its chemical and physical characteristics, leading to better plant growth and development and increasing yield. The study presents a pot experiment with lettuce on leached cinnamon forest soil (Chromic Luvisol). Research has studied changes in soil NPK before and after vegetation and the effects of the compost on plant production and quality. Increasing the amount of compost in the soil substrate led to an increase in the fresh mass and yield of lettuce and to an increase in the accumulated N, P, and K (%) in the plant tissues (R2=0.91, 0.96 and 0.68, respectively). After the experiment\u27s conclusion, the soils remained very well stocked in P2O5 content. The K2O stock in the soil was medium, i.e. when compost is applied, plant-available potassium increases relative to the initial soil. Total N remained very low; the applied composts provided large amounts of nitrogen for growing lettuce but did not leave the soil in good ecological status

Impact of Compost Application Rate on Lettuce Plant Growth and Soil Agrochemical Status

One way to reduce environmental stress and safeguard soil fertility and ecological sustainability in crop production is by adding compost to the soil substrate. Supplying the soil with organic matter improves its chemical and physical characteristics, leading to better plant growth and development and increasing yield. The study presents a pot experiment with lettuce on leached cinnamon forest soil (Chromic Luvisol). Research has studied changes in soil NPK before and after vegetation and the effects of the compost on plant production and quality. Increasing the amount of compost in the soil substrate led to an increase in the fresh mass and yield of lettuce and to an increase in the accumulated N, P, and K (%) in the plant tissues (R2=0.91, 0.96 and 0.68, respectively). After the experiment\u27s conclusion, the soils remained very well stocked in P2O5 content. The K2O stock in the soil was medium, i.e. when compost is applied, plant-available potassium increases relative to the initial soil. Total N remained very low; the applied composts provided large amounts of nitrogen for growing lettuce but did not leave the soil in good ecological status

Влияние на торенето върху износа на макроелементи с биомасата на слънчоглед

The study was conducted under pot experimental conditions with Alluvial-meadow soil. The aim of the trial was to evaluate the effect of different nitrogen, phosphorus, potassium, and silicon fertilizer rates in the soil and their impact on the uptake of basic macronutrients with sunflower (Helianthus annuus L.) biomass. The experiment included 16 variants of increased fertilizer rates in 3 replications. Data on the yield of fresh and absolutely dry biomass from the aboveground part of plants and on the content of N, P, K, Si, Ca and Mg in the dry biomass was obtained. According to the data obtained, the content and uptake of the examined macroelements with the sunflower biomass were significantly influenced by the rates and fertilizer combinations. The highest uptake of nitrogen was in the variants with the following rates: N200, N300, and N400. The changes in the macroelements’ uptake followed the changes in the quantities of the relevant elements in dry biomass in the variants of the experiment. By increasing the fertilizer rates the content of N, P, and Si, and their uptakes with sunflower biomass was increased. This trend with potassium was expressed to a lower extent.Проведено е изследване в условията на съдов опит върху Алувиално-ливадна почва. Целта на експеримента е да се оцени ефективността и взаимодействието на различни норми на азотни, фосфорни, калиеви и силициеви торове в почвата и влиянието им върху износа на основни макроелементи с биомасата от слънчоглед (Helianthus annuus L.). Опитът включва 16 варианта на торене с 3 повторения. Получени са данни за добива от свежа и абсолютно суха биомаса от надземната част и съдържанието на N, P, K, Si, Ca и Mg в получената суха биомаса от растенията. Съгласно получените експериментални данни съдържанието и износът на изследваните макроелементи с биомасата са повлияни значително от торовите норми и комбинации. Най-висок е износът на азота във вариантите с норма N200, N300 и N400. Установено е, че измененията на износите на изследваните макроелементи следват измененията на количествата от съответните елементи в сухата биомаса по варианти в опита. С повишаване на нормите на торене се повишава не само съдържанието, но и износът на N, P, и Si. При калия тази тенденция е изразена в по-малка степен

Effect of Nitrates, Thiocyanates and Selenium on the Iron and Iodine Status of Postpartum Women

Aim: To find correlations between high thiocyanate and nitrate levels and low selenium levels and the indicators of the iodine and iron status of postpartum women