Water Magnetization and Application of Soil Amendments Enhance Growth and Productivity of Snapdragon Plants

Freshwater resources are being rapidly depleted because of the increased demand resulting from exponential world population growth and the effects of climate change, especially in arid and semiarid regions (e.g., Saudi Arabia). The present study aimed to examine the changes in growth and inflorescence production of snapdragon (Antirrhinum majus L.) plants in response to irrigation with saline or magnetized water, in addition to application of inorganic and/or organic soil amendments. Three different water types—tap water, magnetized saline water, and nonmagnetized saline water—were used to irrigate A. majus plants with or without soil amendments consisting of ferrous sulfate (Fe2SO4) and/or peatmoss. Irrigation with magnetized saline water adversely affected vegetative growth, inflorescence production, mineral contents, and survival rates of A. majus plants as compared with irrigation with tap water or magnetized saline water. Nevertheless, compared with unmagnetized saline water treatment, magnetizing nonmagnetized saline water before irrigation significantly improved water characteristics and plant growth and survival. Moreover, the addition of inorganic or organic soil amendments enhanced the growth of A. majus plants regardless of irrigation water type. Interestingly, the combination of irrigating with magnetized saline water and soil amendments (Fe2SO4 and peatmoss) significantly enhanced the growth of A. majus plants to a level that was comparable to that of control plants irrigated with tap water without soil amendments. Magnetization improved water quality and increased plants’ ability to absorb water and nutrients from soil solution. The utilization of magnetized saline water for irrigating food and forage crops either alone or in combination with soil amendments has potential benefits that warrant further research.

Pilot Study of Eco-Physiological Pepper Responses to Starfish-Based Organic Soil Amendments in Open-Field and Greenhouse Cultivations

This pilot study was conducted to compare eco-physiological responses to starfish (SF)-treated red peppers (Capsicum annuum L.) in organic open-field (OF) and greenhouse (GH) cultivations in commercial farmhouses, South Korea in 2019. Treatments included starfish-liquid fertilizer (LF) applied in OF (SF-OF) and GH (SF-GH) plots, and SF + seaweed in OF (SFS-OF) and GH (SFS-GH). Weekly pH levels in SFS-LF were fluctuated for a 16-week storage period at room temperature due to having higher soluble salt levels than those of SF-LF. All experimental plots were ranged on soil pH between 7.1 and 7.4. SF- and SFS-GH plots resulted in increased soil electrical conductivity, organic matter, and increased concentrations of total nitrogen, phosphorous pentoxide, potassium oxide, and magnesium oxide, as well as exhibiting a richer and more diverse bacterial community. Leaf width and length and plant height increased in plants cultivated in GH, with low canopy width and stem diameter also observed to have increased. Total fruit yields were approximately two times higher for peppers cultivated in GH compared to OF cultivated peppers.

Organic soil amendments as a tool to increase biological activity and C sequestration in clay soil

<p>Soil C sequestration through improved agricultural management practices has been suggested to be a cost-efficient tool to mitigate climate change as increased soil C storage removes CO<sub>2</sub> from the atmosphere. In addition, improved soil organic carbon (SOC) content has positive impacts on farming though better soil structure and resilience against climate extremes through e.g. better water holding capacity. In some parts of the world, low SOC content is highly critical problem for overall cultivability of soils because under certain threshold levels of SOC, soil loses its ability to maintain essential ecosystem services for plant production. Soil organic amendments may increase soil C stocks, improve soil structure and boost soil microbial activities with potential benefits in plant growth and soil C sequestration. Additional organic substrates may stimulate microbial diversity that has been connected to higher SOC content and healthy soils.</p><p>We performed a two-year field experiment where the aim was to investigate whether different organic soil amendments have an impact on soil microbial parameters, soil structure and C sequestration.</p><p>The experiment was performed in Parainen in southern Finland on a clay field where oat (Avena sativa) was the cultivated crop. Four different organic soil amendments were used (two wood-based fiber products that were leftover side streams of pulp and paper industry; and two different wood-based biochars). Soil amendments were applied in 2016. Soil C/N analysis was performed in the autumns 2016-2018 and soil aggregate in the summer and autumn 2018, as well as measures to estimate soil microbial activity: microbial biomass, soil respiration, enzymatic assays, microbial community analysis with Biolog ®  EcoPlates and litter bag decomposition experiment. The relative share of bacteria and fungi was determined using qPCR from soil samples taken in the autumns 2016, 2017 and 2018.</p><p>Data on how the studied organic soil amendments influence soil structure and C content, as well as soil microbial parameters will be presented and discussed.</p>

Effects of organic soil amendments on soil greenhouse gas exchange under controlled soil moisture conditions

<p>Organic soil amendments are proposed to mitigate climate change and support soil fertility by introducing recalcitrant carbon into soil. However, the full impact of recycled biosolids on soil greenhouse gas (GHG) dynamics are still unknown. We conducted a laboratory incubation to assess the climatic effects of two biochars (willow and spruce) and two ligneous biosolids on GHG emissions in controlled moisture conditions. The soil used in the incubation was collected from a soil-amendment field experiment on a clay cropland in South-West of Finland. The soil was sieved, air-dried and then individual samples were adjusted to 25%, 50%, 80% and 120% of water filled pore space (WFPS) before being incubated for 32 days in laboratory conditions. Soil GHG fluxes were measured after 1, 5, 12, 20 and 33 days.  </p><p>The application of 20–40 Mg ha<sup>-1</sup> of ligneous amendments, two years prior to our experiment, had increased soil pH, soil organic carbon content and plant available water content. The carbon dioxide (CO<sub>2</sub>) fluxes were unaffected by the amendment treatments and correlated mainly with soil moisture and microbial biomass. Nitrous oxide (N<sub>2</sub>O) emissions were reduced by all amendments compared to the un-amended control. Methane (CH<sub>4</sub>) exchange consisted mostly of slight uptake by the soil but played only a minor role in the total GHG budget overall. </p><p>The sum of CO<sub>2</sub>, N<sub>2</sub>O and CH<sub>4</sub> emissions, calculated as CO<sub>2</sub>-equivalents, exhibited a strong linear relationship with soil moisture. Where the GHG budget was dominated by CO<sub>2</sub>, it was accompanied by significant N<sub>2</sub>O emissions at 120% WFPS. The results indicate that soil moisture critically affects the GHG emissions and that while organic soil amendments may have persisting effects on GHG exchange, they primarily occur in water-saturated conditions through N<sub>2</sub>O dynamics.</p>

Comparative Role of Compost, Press Mud and Moringa Leaf Extract to Eliminate the Stress and Growth of Maize in Cadmium Polluted Soil

Cadmium contamination in croplands is recognized as one of the major threats, seriously affecting soil health and sustainable agriculture around the globe. Cd mobility in wastewater irrigated soils can be curtailed through eco-friendly and cost effective organic soil amendments compost (CP), press mud (PM) and moringa leaf extract (ME) at 3% rate that eventually reduces its translocation from polluted soil to plant. This study explored the possible effects of various types of organic soil amendments on cadmium (Cd) phytoavailability in wastewater degraded soil and its subsequent accumulation in maize tissues. Maize plant was grown in Ghazi University as a test plant and Cd accumulation was recorded in its tissues, translocation from root to shoot, chlorophyll contents, plant biomass, yield and soil properties (pH, NPK, OM and Soluble Cd) were also examined. Results revealed that the addition of amendments significantly minimized Cd mobility in soil by 45.8%, 23% and 19.4% when CP, PM and ME were added at 3% over control. Comparing the control soil, Cd uptake effectively reduced via plants shoots by 33.3%, 27.7% and 19.4% when CP, PM and ME. In addition, NPK were significantly increased among all the added treatments in the soil-plant system as well as improved chlorophyll contents relative to non-treated soil. The Current study suggested that among all the amendments, compost at 3% rate performed well and might be considered a suitable approach for maize growth in polluted soil.