Content Of Available Potassium In Soil Research Articles

A study on soil fertility status of adopted model village in Rahuamani, Kahra block of Saharsa district in Bihar

Soil fertility assessment in a region is the most basic decision-making tool for sustainable soil nutrient management. A soil fertility status inventory work was carried out in adopted model village, Rahuamani of Kahra block in Saharsa district. One hundred soil samples were randomely collected based on the handled GPS location. Results showed that 91% samples were found in neutral reaction and all the samples fall under normal and safe category of electrical conductivity. Sixty-five per cent soil samples fall under lows organic carbon content and 35% samples were medium in organic carbon content. 61% of the study area was deficient in available N and 81% samples were fall under medium category of fertility status of P5O5. The available potassium content in soil, 90% of the soil samples were medium fertility level. It was found that 75% samples were in medium soil sulphur category. Zn content of the study are fall under the medium fertility category. Similarly, 58% sample deficient in copper content and 47% sample are deficient in available Mn. Out of total soil sample analyzed 78% samples are deficient in B content in soil.

Nutrient uptake, soil nutrient status and water use efficiency as influenced by drip fertigation in broccoli (Brassica oleracea var. italica)

Nutrient uptake by plant and nutrient status of soil after harvesting of crop varies markedly under fertigation and soil fertilization. A two year experiment was conducted at Vegetable Research Centre of G.B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India during the rabi seasons of 2016–2017 and 2017–2018 to study the effect of drip fertigation with levels and scheduling on nutrient uptake, soil nutrient status and water use efficiency in broccoli. The experiment was laid out in two factorial randomized block design with one additional treatment consisting of five fertigation levels and three fertigation scheduling along with control (soil application of RDF with flooding) replicated thrice. Increasing the fertigation levels favors in increasing the nitrogen, phosphorus and potassium uptake irrespective of the crop growth stage. At harvest, N, P and K uptake by broccoli under fertigation increased by 10.47, 17.39, 12.21% and 18.08, 15.88, 9.96% compared to the soil fertilization in the first and second year, respectively. Fertigation treatment increased the available phosphorus by 11.73 kg compared to soil fertilization. Available potassium content in soil after harvesting of crop depleted when compared to initial value. The consumptive water used for both the years varies between 150 mm and 195 mm under different fertigation treatments as compared to 300–325 mm under traditional method of irrigation. Fertigation treatments registered significantly higher WUE of 78.31 kg ha−1 mm−1 and it was higher by 95.48% over the conventional method of irrigation (40.06 kg ha−1 mm−1).

Impact of INM and intercrop on soil properties under Teak (Tectona grandis L. f.) based agroforestry system

The present investigation entitled “Impact of integrated nitrogen management and intercrop on soil properties under Teak (Tectona grandis L. f.) based agroforestry system” was carried out during summer season of the year 2019 and 2020. Okra var. GAO-5 grown as an intercrop at College Farm, N. M. College of Agriculture, Navsari Agricultural University, Navsari, Gujarat, India. The trial was framed with twelve different treatments comprised of combinations of vermicompost, neem cake and chemical fertilizers in various proportions i.e. 25 per cent, 50 per cent, 75 per cent and 100 per cent of recommend does of nitrogen in the form of organic and inorganic fertilizers under teak plantation and open condition in Randomized Block Design (RBD) consisting of three replications. Minimum soil pH (7.46), EC (0.652) and maximum available nitrogen (333.05 kg ha-1) and SOC (0.860%) content in soil were noted in T8: 100% RDN through Vermicompost under teak based agroforestry system. While, available phosphorus content (92.90 kg ha-1) in soil at harvest of okra crop was recorded maximum in T9: 100% RDN through Neem cake under teak based agroforestry systems. At the time of okra harvest available potassium content in soil was found maximum (734.04 kg ha-1) in T12: 75% RDN from Neem coated urea + 25% RDN through Vermicompost in open condition. Whereas, maximum soil pH (7.76), EC (0.921) and lowest available nitrogen (265.22 kg ha-1), phosphorus (69.46 kg ha-1), SOC (0.477%) was noted in T11: 100% RDF through chemical fertilizer in open condition. Moreover, lowest available potassium in soil (537.30 kg ha-1) was registered in T10: sole tree crop. From the study it can be concluded that majority of the soil chemical properties are improved under teak based agroforestry system as compared to open filed condition.

Development of the Selected Properties of Zinc-Contaminated Soil Following an Addition of Neutralising Substances

Studies have been undertaken which assess the possibility of neutralising the effect of zinc on the contents of: organic carbon, total nitrogen, available forms of: phosphorus, potassium and magnesium in soil by applying neutralising substances – compost, bentonite and zeolite. In the series without an addition of neutralising substances, increasing zinc soil contamination resulted in an increase in the contents of total nitrogen, available forms of phosphorus, magnesium and potassium (especially), and a decrease in the organic carbon content, compared to the control object (without Zn). Application of bentonite and zeolite had an advantageous effect on the contents of carbon and available phosphorus and on the C:N ratio in soil, compared to the series without additions. Bentonite had a similar effect on the available potassium content in soil. It had a much greater effect on the organic carbon content in soil than zeolite. Not all of the neutralising substances added to soil had a significant effect on the contents of nitrogen and available magnesium in soil, compared to the series without neutralising substances.

Impact of Microbial Inoculants on Microbial Quantity, Enzyme Activity and Available Nutrient Content in Paddy Soil

The experiment was conducted to study the impact of application of microbial inoculants, compared with no microbial fertilizer, on enzyme activity, microbial biomass and available nutrient contents in paddy soil in Heilongjiang Province. The application of soil phosphorus activator was able to increase the quantity of bacteria and fungi in soil, but its effect on actinomycetes in soil was not significant. The application of microbial inoculants increased the urease and sucrase activities in soil over the growing season, but only at the maturing stage soil acid phosphatase activity was enhanced with the applying soil phosphorus activator. The application of soil phosphorus activator increased alkali-hydrolyzable nitrogen and available phosphorus contents in soil, but did not increase available potassium content in soil. The optimal microbial inoculant application rate as applied as soil phosphorus activator was 7.5 kg·hm−2.

Quantitative Assessment on Spatial Suitability for Tobacco Planting in Bozhou in Northern Anhui Province, China

While Qiaocheng district currently is the main tobacco planting region in Northern Anhui Province, China, the quantitative assessment on spatial suitability for tobacco planting is necessary for the scientific instruction in the adjustment of planting regionalization and fertilization. In this paper, soil samples of the plough layers were collected from 1224 typical farmlands in 2008, and 18 types of soil properties, pH, clay, silt, sand, organic matter, total nitrogen, available phosphorus, slowly available potassium, rapidly available potassium, exchangeable Ca2+ and Mg2+, Cl-, HCO3-, SO42-, available Fe, Mn, Cu and Zn were measured. Meanwhile irrigation water samples of 90 typical pumping wells were collected, and Cl-, HCO3-, SO42-, K+, Ca2+ and Mg2+ were measured. The above measured properties were used as the assessing indexes for spatial suitability for tobacco planting, in which the weights were generated by the method of principal component analysis and the fuzzy membership functions were produced based on the practical experiences with the related literatures. The soil suitabilities were quantitatively assessed using the ArcGIS 10.0 platform. The experimental results showed that: (1) areas of the highest, higher, middle, lower and lowest levels of suitability are 4.28×104, 4.36×104, 4.82×104, 4.47×104 and 4.81×104 hm2. respectively, constituted of 18.84%, 19.16%, 21.20%, 19.66% and 21.14% of the total area of the farmland, respectively; (2) in general, the Northeast, Northwest, Southeast and Southwest regions are the most suitable areas, and (3) for tobacco farmland in the North region, more potassium fertilizers should be applied due to the low available potassium content in soil, and the flood irrigation should be prevented due to the high content of Cl- in irrigation water. Chengfu in the Sourtheast, Shihe and Feihe in the Southwest, and Longyang and Gucheng in the South could be regarded as the new potential tobacco planting regions.

Available Potassium Content in Soil under Intensive Fertilizer use as revealed by Some Soil Tests

An investigation was undertaken to examine the changes in available potassium status in an alluvial soil under intensive cropping and fertilizer use for seven years, using water, 0.01M CaC1, neutral normal ammonium acetate and NHF plus DTPA as coil tests. While all the four tests employed were found fairly effective, ammonium acetate proved to be the best in detecting the treatmental differences. CeC1, (001M), ammonium acetate and NH.F plus DTPA showed highly significant positive relationships with yield of crops raised in the eighth rotation.