Influence of Planting Soil Mix Characteristics on Bioretention Cell Design and Performance
Municipalities are increasingly interested in using rain gardens, or bioretention cells, as a “best management practice” (BMP) for storm-water management and as a component of low impact development. However, improved technical reference materials are needed to determine the influence of planting soil mix design on the hydrologic and water quality performance of bioretention cells. This article describes three investigations undertaken to determine the influence of planting soil mix characteristics. The first was to identify the bioretention cell design characteristics and methodologies used by different agencies. The second was a laboratory investigation on the soil characteristics that influence performance including field capacity, saturated hydraulic conductivity, soil moisture content, organic content, dry bulk density, porosity, and sediment grain size distribution. The third was to quantify the effectiveness of bioretention cells as a storm-water BMP by designing, constructing, and monitoring two full-scale bioretention cells on the campus of Lawrence Technological University in Southfield, Mich. Analysis included quantifying volume retention, peak discharge reduction, and removal of storm-water pollutants including total suspended solids, total phosphorus, and total nitrogen.
 Comprehensive assessment for the residual characteristics and degradation kinetics of pesticides in Panax notoginseng and planting soil
Incorrect and excess usage of pesticides during crop cultivation poses a serious threat to human health and ecosystems. In this study, we tested for the presence of 201 pesticide residues in 90 batches of Panax notoginseng (P. notoginseng) and 10 batches of planting soil. Pesticide residue characteristics and the relationship between pesticides present in P. notoginseng and the soil were discussed. Twenty-nine pesticides were detected in P. notoginseng samples and 15 pesticides were found in the soil samples. In P. notoginseng samples, the 68.9% of the identified pesticides were fungicides, and six fungicides (procymidone, iprodione, pyrimethanil, propiconazole, dimethomorph and tebuconazole) were found in >90% of the samples. Nine insecticides were found, with one insecticide, chlorpyrifos, detected in 93.3% of the P. notoginseng samples.
 The variable response of dryland corn yield to soil water content at planting
Farmers in the central Great Plains want to diversify crop rotations from the traditional monoculture system of winter wheat-fallow. Corn (Zea mays L.) could work well as a rotation crop, but inputs are expensive and farmers would like to know the chances of producing a certain yield before investing in seed, fertilizer, herbicides, etc. Information on the yield response of corn to available soil water at planting could help guide the crop choice decision regarding corn. This study was conducted to determine if a predictive relationship exists between dryland corn yield and available soil water at planting time and, if such a relationship exists, to use it to assess the risk in obtaining profitable yields. Yield and soil water data from 10 years of a dryland crop rotation study at Akron, CO were analyzed by linear regression to determine predictive relationships. The yield-soil water content production function was highly variable, with values ranging from 0.0 to 67.3 kg ha−1 per mm of available soil water in the 0 to 1.8 m soil profile at planting.
 Root properties of plants used for soil erosion control in the Usambara Mountains, Tanzania
Plant roots may have a strong erosion-reducing effect. However, little is known about root characteristics of tropical plants used for erosion control. A study was thus conducted in the Western Usambara Mountains, Tanzania to investigate rooting characteristics of Guatemala grass (Tripsacum andersonii), Napier grass (Pennisetum purpureum) and Tithonia shrub (Tithonia diversifolia), also referred to as wild sunflower, and to evaluate their potential for erosion control. For each plant species, mean root diameter (D), root density (RD), root length density (RLD) and root area ratio (RAR) were assessed for six plants in each species and relative soil detachment rate (RSD) predicted. Mean RD values in the 0 – 0.4 m soil depth for Majulai village and Migambo village respectively 3 3 were 50.9 and 58.6 kg/m for Guatemala grass, 30.4 and 31.3 kg/m for Napier grass and 3 3 22.1 and 23.0 kg/m for Tithonia shrub. RLD values were 35.9 and 45.0 km/m for 3 3 Guatemala grass, 31.3 and 150.0 km/m for Napier grass and 10.5 and 6.4 km/m for -12 -14 Tithonia shrub. Predicted RSD values were 4.43*10 and 1.20*10 for Guatemala -5 -4 -3 -4 grass, 6.10*10 and 2.74*10 for Napier grass and 4.43*10 and 2.24*10 for Tithonia shrub in the 0 – 0.4 m soil depth. The results indicate that Guatemala grass has a higher potential to reduce soil erosion rates by concentrated flow as compared to Napier grass or Tithonia shrub in the 0 – 0.4 m soil depth. These findings have implications on the selection and use of appropriate plants for soil erosion control.
 Effect of Unconventional Phosphorus Sources and Phosphate Solubilizing Bacteria on Fractions of Phosphorus in a Calcareous Soil Cultivated with Wheat Plants
A pot experiment was conducted at the experimental farm of Faculty of Agriculture, Ain Shams University, Egypt. To study the effect of recycling fish bone and bone meal as well as rock phosphate in a comparison with the ordinary superphosphate on the fractionation and availability of phosphorus in a calcareous soil. These treatments combined with or without adding specific bacteria. Wheat plants were grown under these treatments and their combinations to evaluate the residual effect of such treatments compared to the control (without any treatment) under different physiological stages of grown plants. Generally, the non-traditional phosphorus sources could succeed to substitute the ordinary superphosphate, as a source of phosphorus for soil and wheat plants, especially with addition of specific P-dissolving bacteria. The treatments of ½ OSP+FB and FB alone with adding P solubilizing bacteria were the best, which gave an acceptable results for the availability and fractions of P in the studied calcareous soil, more than giving a vigor plant growth compared with the other treatments. It means that recycling house wastes such as these unconventional P sources can replace with the traditional P sources without any contamination to the soil and growing plants with heavy elements, considering them environmentally friendly.
 Carpenter, D.D. and Hallam, L., 2010. Influence of planting soil mix characteristics on bioretention cell design and performance. Journal of Hydrologic Engineering, 15(6), pp.404-416.
 Fu, Y., Dou, X., Lu, Q., Qin, J., Luo, J. and Yang, M., 2020. Comprehensive assessment for the residual characteristics and degradation kinetics of pesticides in Panax notoginseng and planting soil. Science of the Total Environment, 714, p.136718.
 Nielsen, D.C., Vigil, M.F. and Benjamin, J.G., 2009. The variable response of dryland corn yield to soil water content at planting. Agricultural water management, 96(2), pp.330-336.
 Mwango, S.B., Msanya, B.M., Mtakwa, P.W., Kimaro, D.N., Deckers, J., Poesen, J., Massawe, V. and Bethuel, I., 2014. Root properties of plants used for soil erosion control in the Usambara Mountains, Tanzania.
 Abd-Elrahman, S.H., 2016. Effect of Unconventional Phosphorus Sources and Phosphate Solubilizing Bacteria on Fractions of Phosphorus in a Calcareous Soil Cultivated with Wheat Plants. International Journal of Plant & Soil Science, pp.1-11.