Buffering strips

Buffering strips Reduce soil erosion Lacas et al. (2009)... 

Elute 20 CV linear gradient to 100% elution buffer Strip 5 CV elution buffeC... 

Benoit, P., Barriuso, E.. Vidon, Ph., and Real, B. Isoproturon sorption and degradation in a soil from grassed buffer strip. /. Environ. Qual, 28(1) 121-129, 1999. 

Patty, L., B. Real, and J.J. Gril (1997). The use of grass buffer strips to remove pesticides, nitrate, and soluble phosphorus compounds from runoff water. Pestic. Sci., 49 243-251. 

Farmers are environmental stewards and are applying many BMPs to reduce erosion and improve water quality. BMPs can be structural (e.g., a mixing-loading pad) or nonstructural (e.g., a tillage practice, vegetative buffer strip, or other agricultural practices). As the adoption of BMPs increases, levels of pesticides, nutrients, and sediment in water will continue to decline. 

Schwer and Clausen (1989) reported that a fescue/ryegrass/bluegrass filter strip retained 89% of the phosphorus from dairy milk-house wastewater. Vought et al. (1994), summarizing his own research on phosphorus removal from surface runoff, noted exponential removal with 66% and 95% of soluble phosphorus retained in the first 8 and 16m of buffer strip, respectively. Daniels and Gilliam (1996) determined that fescue and riparian filter strips reduced total phosphorus load by 50%, but that 80% of the soluble phosphorus frequently moved through the strips. 

Only 50% of total nitrogen was bound to sediment (Schreiber et al., 1980). Nitrate uptake appeared to be linear with distance from the source, with an average of 20% and 50% removal in the first 8 and 16m of buffer strip, respectively (Vought et al., 1994). Jordan et al. (1993) found that most of the drop in nitrate levels within the riparian zone occurred abruptly at the edge of a floodplain within the forest, where the water table was nearest the surface and strong reducing conditions existed. 

A vegetative filter strip reduced losses of metribuzin and metolachlor by more than 85% (Webster and Shaw, 1996). Grassed waterways reduced loads of 2,4-D by 69% and 71% under wet and dry conditions, respectively (Asmussen et al., 1977), while trifluralin retention dropped from 96% under dry conditions to 86% under wet conditions (Rhode et al., 1980). A 6-m vegetative buffer strip composed of trees, shrubs, and grass almost completely removed terbuthylazine from runoff (Vianello et al., 2005). Oats as a strip crop below corn reduced atrazine runoff losses by 91% and 65% after applications of 2.2 and 4.5kg/ha, respectively (Hall et al., 1983). Atrazine and metolachlor concentrations in runoff were reduced 83-94% and 82-96%, respectively, with 4.3- and 8.5-m vegetative filter strips (Barone et al., 1998). 

Arora, K., S.K. Mickelson, J.L. Baker, D.P. Tierney, and C.J. Peter (1996). Herbicide retention by vegetative buffer strips from runoff under natural rainfall. Trans. Am. Soc. Agric. Eng., 39(6) 2155-2162. 

Bharati, L. (1997). Infiltration in a Coland clay loam under a six-year old multi-species riparian buffer strip, cultivated row crops and continually grazed pasture. M.S. Dissertation, Iowa State University, Ames, IA. 

Hickey, M.B.C. and B. Doran (2004). A review of the efficiency of buffer strips for the maintenance and enhancement of riparian ecosystems. Water Qual. Res. J. Canada, 39(3) 311-317. 

Mickelson, S.K. and J.L. Baker (1993). Buffer strips for controlling herbicide runoff losses. Paper No. 932084. 1993 International Summer Meeting, American Society of Agriculture Engineers, Spokane, WA. 

Reed, T. and S.R. Carpenter (2002). Comparisons of P-yield, riparian buffer strips, and land cover in six agricultural watersheds. Ecosystems, 5(6) 568-577. 

Reungsang, A., T.B. Moorman, and R.S. Kanwar (2001). Transport and fate of atrazine in midwestem riparian buffer strips. J. Amer. Water Res. Assoc., 37(6) 1681-1692. 

Phosphamidon. Phosphamidon was introduced into Canadian spruce budworm control programs in the mid-60s to reduce the adverse effects on aquatic organisms, particularly Atlantic salmon stocks, which had accompanied the use of DDT in previous programs. Its relatively low toxicity to fish led to the application of phosphamidon within buffer strips along streams and rivers inside large DDT spray blocks. These protective measures greatly reduced fish losses within DDT treated areas (20). Phosphamidon has also been shown to have only limited effects on aquatic insects (21, 22). 

There is finally the interaction between the paper and the protein or other ions migrating on the buffered strip. Adsorption of the migrating ion on the cellulose resists the driving force of the electrical field. As adsorption is different for each component of a mixture, it may alter the... 

Some investigators apply the sample some distance from the desired starting line and use evaporation to move the sample toward it, thus obtaining in effect a partial dialysis. True dialysis can be achieved with the usual methods, and for micro samples Antweiler (A6) gives a successful technique. A rapid and ingenious method is dilution of the sample with buffer, followed by concentration on an ultrafilter, on which electrophoresis is subsequently performed (unpublished). Better knowledge of the physical conditions of the buffered strip will increase the use of a dialyzing technique in order to obtain better results. 

The chemical form of phosphorus in the water column available for uptake by biota is important. The biologically available phosphorus is usually taken to be soluble reactive phosphorus (orthophosphate) , i.e. which, upon acidification of a water sample, reacts with added molybdate to yield molybdophosphoric acid, which is then reduced with SnCl2 to the intensely-coloured molybdenum blue complex and is determined spectrophotometrically (Imax = 882 nm). Reduction in inputs of phosphate, for example from point sources or by creating water meadows and buffer strips to contain diffuse runoff, has obviously been one of the major approaches to stemming eutrophication trends and... 

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