http://lqma.ifas.ufl.edu/Publication/Cao-09a.pdf
Environmental Implication.
Results from this study indicated that dairy manure can be converted into biochar as a unique sorbent for both metals and organics, implying that manure can potentially serve as a remediation amendment. In the United States, 350 billion tons of manure are generated annually (29). Land application of manure to fertilize soil as a common method for managing dairy manure has caused a serious environmental issue, i.e., high levels of P accumulated in the soils receiving long-term manure applications led to P enrichment and water quality dete- rioration in aquatic systems (30). Therefore, turning dairy manure into biochar as a sorbent is a “win-win†solution via improving waste management and protecting the environment. Several studies have successfully converted animal waste into activated carbon (AC) as sorbent for environmental remediation (31). However, production of AC needs higher temperature and additional activation processing, which require more energy and higher production cost. In comparison, biochar can be produced at low temperature for direct use, consuming less energy. Furthermore, previous work consistently shows that biochar generated from other sources such as crop residues, peat, and wood is only effective in sorbing organic contaminants (12), whereas most contaminated sites contain both heavy metals and organic pollutants. Therefore, it is advantageous to produce a sorbent such as manure-derived biochar, which can remove both metals and organics. High content of P in the biochar is mainly responsible for Pb retention via formation of stable phosphate minerals, with less contribution from surface sorption, whereas atrazine sorption is attributed to its partitioning into the noncarbonized organic phase. However, more studies are needed to verify remediation efficacy of the biochar for sorption of other heavy metals (e.g., Cd and Hg)
and organic contaminants (e.g., PAHs and PCBs).
Atrazine is used to stop pre- and post-emergence broadleaf and grassy weeds in major crops. Atrazine is the most widely used herbicide in conservation tillage systems, which are designed to prevent soil erosion. 76 million pounds of atrazine were applied in the United States in 2003.
ReplyDeleteAtrazine is a widely used herbicide utilized by farmers to control and prevent weeds from growing among crops, especially corn. Public safety measures have increased through the years because of the health risks associated with Atrazine use. Its detrimental effects on ecosystems have also alerted environmental care groups. With proper handling and application, however, Atrazine can provide benefits for agro-industries in a safe, efficient manner.
ReplyDeleteSince the 1950s, Atrazine has been favored in the fight against weeds that prevent abundant yields, or harvests. It also doesn't cause injury to crops and is adaptable to most soil systems. More than 65 percent of America's corn crops are treated with Atrazine. Herbicide workers also spray the chemical over highways and railroad paths.
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