Germination of Bouteloua dactyloides and Cynodon dactylon in a Multi-Polluted Soil

Abstract

Abstract:Mining wastes generate high environmental impacts, and population exposure to metals and metalloids. Phytoremediation is a technology that uses plants to remediate polluted sites, but one of its limitations is seed germination in soil with a high content of metals and metalloids. Bouteloua dactyloides (former Buchloe dactyloides) is a native species from semiarid regions, while Cynodon dactylon is an invasive species; both are tolerant to harsh soil conditions. The objective of this research was to evaluate the germination of both species, exposed to a multi-polluted soil with As, Cd, Pb, and Zn of a mining site, considering different pH conditions (from 5.0 to 9.0). The study considered four repetitions by type of seed and soil pH. The highest germination of B. dactyloides was 83% at pH 7.8, while the greatest germination of C. dactylon was 34% at pH 6.0. These percentages are similar to those obtained in a standard germination test, which are 82.5% for B. dactyloides and 35% for C. dactylon. Germination was not reached in either species with soil at pH 5, owing to the fact that metals are more bioavailable in acid environments. B. dactyloides and C. dactylon had a high potential to germinate in multi-polluted soil at neutral pH, but further experiments are needed.

Cadmium Hyperaccumulation and Translocation in Impatiens Glandulifera: From Foe to Friend?

“…Cadmium is one of the most important, toxic, and widely distributed pollutants in our environment. Naturally occurring levels of Cd are typically <1 mg/kg, but over two centuries of industrialization has led to cadmium levels of over 1000 mg/kg in some geographical regions [2][3][4][5]. Anthropogenic sources of Cd include water discharge from industrial plants, mining and smelting, sewage sludge, and disposal of materials containing heavy metals, e.g., electronics, rechargeable batteries, fertilizers, steel, and pigments [1,3,6,7].…”

“…Average European values are included in the text bubble, while sites with elevated levels of Cd (due to anthropogenic activities) are denoted by location pins. Mining and smelting are largely responsible for some of the most heavily polluted regions [4,5,[8][9][10][11][12][13][14].…”

“…Cadmium can also reduce plant biomass, the numbers of flowers or fruits, chlorophyll content, and the ability to uptake essential plant nutrients [2,3]. Cadmium is highly mobile, as it has similar physiochemical properties to essential micronutrients such as zinc, enabling it to be readily taken up by plants [4,15,16]. Phytoextraction is a form of phytoremediation where pollutants are removed from the soil using plants that can accumulate and bioconcentrate pollutants in its tissues, thereby remediating the soil [17,18].…”

“…Phytoextraction is a form of phytoremediation where pollutants are removed from the soil using plants that can accumulate and bioconcentrate pollutants in its tissues, thereby remediating the soil [17,18]. Phytoremediation is a sustainable, efficient, and cost-effective means of rectifying and restoring soil and water to their natural conditions [4,19]. The efficacy of phytoremediation is dependent on the properties of the plant, the bioavailability of the heavy metal(s), and the characteristics of the soil [4,6,20].…”

“…Phytoremediation is a sustainable, efficient, and cost-effective means of rectifying and restoring soil and water to their natural conditions [4,19]. The efficacy of phytoremediation is dependent on the properties of the plant, the bioavailability of the heavy metal(s), and the characteristics of the soil [4,6,20]. The most suitable phytoremediation plants are fast growing with high biomass production that can tolerate and accumulate high levels of the pollutant.…”