Effect of Polyacrylamide Application on Water and Nutrient Movements in Soils

An understanding of nutrient movement in soil is important for developing management strategies to minimize nutrient leaching and surface movement, thus improving nutrient uptake by plants, maintaining a sustainable soil system, and even protecting groundwater quality. Polyacrylamide (PAM) is known as one of soil conditioner that functions to stabilize soil structure, increase infiltration, and reduce surface runoff. This study assesses the effects of PAM on the vertical movement of soil-water and major/minor nutrients (NO3-N, NH3-N, T-N, PO4-P, T-P, K, Ca, Mg, and Fe) in soils. Saturated hydraulic conductivity (Ksat) increases with increasing PAM concen- trations up to 10 mg·L-1 for sand and 20 mg·L-1 for a mixture of sand and clay. Decreases in the loss of soluble nutrients, particularly NH3-N, PO4-P and T-P, are observed as PAM concentrations increase. In contrast, PAM concentration has no effect on nitrate and minor nutrient levels. These results indicate that the application of PAM may be a viable method for protecting water bodies from excessive nutrients and improving nutrient availability for plants.

The wonders of earthworms &its vermicompost in farm production: Charles Darwin’s ‘friends of farmers’, with potential to replace destructive chemical fertilizers

Earthworms and its excreta (vermicast) promises to usher in the ‘Second Green Revolution’ by completely replacing the destructive agro chemicals which did more harm than good to both the farmers and their farmland. Earthworms restore & improve soil fertility and significantly boost crop productivity. Earthworms excreta (vermicast) is a nutritive ‘organic fertilizer’ rich in humus, NKP, micronutrients, beneficial soil microbes—‘nitrogenfixing & phosphate solubilizing bacteria’ & ‘actinomycets’ and growth hormones ‘auxins’, ‘gibberlins’ & ‘cytokinins’. Both earthworms and its vermicast & body liquid (vermiwash) are scientifically proving as both ‘growth promoters & protectors’ for crop plants. In our experiments with corn & wheat crops, tomato and eggplants it displayed excellent growth performances in terms of height of plants, color & texture of leaves, appearance of flowers & fruits, seed ears etc. as compared to chemical fertilizers and the conventional compost. There is also less incidences of ‘pest & disease attack’ and ‘reduced demand of water’ for irrigation in plants grown on vermicompost. Presence of live earthworms in soil also makes significant difference in flower and fruit formation in vegetable crops. Composts work as a ‘slowrelease fertilizer’ whereas chemical fertilizers release their nutrients rather quickly in soil and soon get depleted. Significant amount of ‘chemical nitrogen’ is lost from soil due to oxidation in sunlight. However, with application of vermicompost the ‘organic nitro gen’ tends to be released much faster from the excreted ‘humus’ by worms and those mineralised by them and the net overall efficiency of nitrogen (N) is considerably greater than that of chemical fertilizers. Availability of phosphorus (P) is sometimes much greater. Our study sh ows that earthworms and vermicompost can promote growth from 50 to 100% over conventional compost & 30 to 40% over chemical fertilizers besides protecting the soil and the agro ecosystem while producing ‘nutritive and tasty food’ at a much economical cost (at least 50 75% less) as compared to the costly chemical fertilizers.

Balanced Fertilizer Use through Soil Testing Leads to Higher Yields and Nutrient Contents of Maize Grains

Fertilizers use can be optimized through soil testing and leaf analysis. This paper deals with using soil analysis as a base for fertilizer use in maize. A field experiment was carried out in two summer seasons of 2013 and 2014 with maize (triple hybrid) in Oraby Village, Mariut sector, Alexandria, Egypt. Soil testing shows that soil was clay loam, with high Na and CaCO3 contents with high pH, low organic matter, medium P and K and low micronutrient contents (Fe, Zn, Mn and Cu), seven treatments were designed. The most promising treatment was when P and K were increased and micronutrients were added based on soil testing. This treatment resulted in the highest yield with better grain contents of protein and nutrients which indicated that soil-test based on fertilizer use was superior. Soil analysis at the end of the experiment showed higher P and K contents. This approach could be adopted for regions with similar soil conditions in other parts of the world.

Seaweeds as Biomonitoring System for Heavy Metal (HM) Accumulation and Contamination of Our Oceans

This research manuscript reports the heavy metal accumulation in four marine seaweeds sp. 1)?Caulerpa sertlatioides (Cuba);2) Caulerpa cf. brachypus;(Bali, Indonesia);3) Undaria pinnatifida (West-Donegal, Ireland);4) Ulva lactuca (Easters-Scheldt, the Netherlands). Mechanical pressure at 10 bar of fresh seaweed fronds casu quo biomass in the laboratory delivered seaweed moisture which was analyzed by Inductively Coupled Plasma Spectroscopy (ICP)-techniques for heavy-metals = [HM], (Al, As, Cd, Co, Cr, Cu, Fe, Mo, Ni, Pb & Zn). Three important observations were made: 1) The [HM] in the seaweed moisture is higher than in the surrounding seawater which directs to mechanism(s) of bio-accumulation;2) The accumulation factor [AF] is varying per metallic-cation with an overall trend for our four seaweeds and sampling locations for [HM] are: As & Co & Cu: 5000 - 10,000 μg/l;Ni & Zn: 3000 - 5000 μg/l;Cd: 2000 - 3000 μg/l;Cr: 1000 - 2000 μg/l;Al: 200 - 1000 μg/l;Mo & Pb & Fe: 0 - 200 μg/l range. 3) Seaweed moisture detected that [HM]: Pb & Zn & Fe—which all three could not be detected in the seawater—supports the view that seaweeds have a preference in their bio-accumulation mechanism for these three HM. Major conclusion is in general that “overall” for the macro-elements Ca, Fe, K, Mg, Mn, Na, P & S in the moisture of the four seaweed species the concentration is lower in the seaweed species, or equals the concentration, in comparison to the surrounding sea water. For the HM (Al, As, Cd, Co, Cr, Cu, Mo, Ni, Pb & Zn) the opposite is the case species and is the concentration “overall” higher in the seaweed species in comparison to the surrounding sea water. Further topics addressed include strategies of irrigation of the Sahara desert with the moisture out of seaweeds under conditions of low anthropogenic influences.