Location:2009 Annual Report
1a. Objectives (from AD-416)
1)Quantify the ability of best management practices (BMPs) to mitigate the impact of land-use change and extreme climatic events on hydrology and water quality a)Quantify weather and precipitation inputs to watershed models; b)Quantify impacts of land use on runoff and water quality; 2)Quantify the effects of grazing systems on surface runoff and subsurface flow and soil and water quality. 3)Quantify the rate, fate and transport of sediment, nutrients, and agricultural chemicals after implementing agricultural management systems.
1b. Approach (from AD-416)
Precipitation, weather, water-quality, and runoff data will be monitored from experimental watersheds and plots subjected to different conservation, pasture, and land-management practices. Archived data will be used for estimations of baseline and treatment effects, for precipitation studies, and for concept development.
3. Progress Report
-Urbanization: Data collection continues at 4 watersheds, however, few data were collected due to lack of rainfall. A project was started to develop a land suitability index with faculty at the U. of Cincinnati. -Management-Intensive Grazing (MIG): Surface runoff, sediment, and subsurface water samples were collected from the MIG & continuous grazing watersheds. These systems are being compared in regards to forage species composition, animal health and amino acids in milk, and impact on surface and subsurface water and soil. With adequate rainfall, MIG favors greater forage production and length of grazing period; in drier years, little difference is observed. No differences have been observed in the quality of groundwater. -Precipitation studies: A new concept to storm modeling is being tested, wherein both storm depth and storm duration are being simulated in sequence. -Manure plots: For a third winter, beef slurry manure was applied to 4 plots in Jan. on frozen ground; 2 plots were controls. Also, in Jan., 2 watersheds (~2 acres) received turkey manure; 2 watersheds received liquid swine manure in Feb.; and 2 watersheds were controls. Dustpan samplers were installed at the lower edge of the application areas and at 36 ft below this area on plots. Runoff samples were collected and analyzed for nutrients and E. coli and enterococci. Sufficient analysis of data has been performed so that management and treatment changes are planned for next year. Progress is documented among collaborators through site visits, email correspondence, phone calls, and shared data. NAEW soil and air temperatures continue to be entered into a data base for analysis of frozen-soil runoff. -Climate: Weather data were obtained for the entire state of Ohio to expand a study on degree days for grazing at NAEW. Two graduate students from Ohio State University (OSU) are investigating the NAEW 70-yr data base to investigate climate change trends in different parts of the hydrological cycle using NAEW infrastructure. -Soil carbon: In addition to soil sampling and analysis, collaboration continues with 2 OSU scientists who are using isotopic analyses to determine land-use effects on carbon source in runoff. -Filter socks: Runoff data collected in ‘07 and ‘08 for compost-filled filter socks installed in grassed waterway was summarized and submitted for publication in a peer-reviewed journal. Based on these results, the experimental plan was modified to increase the number of socks per waterway by 1 and, rather than mix water treatment residual with the compost to increase nutrient sorption, a proprietary sorbent was mixed with the compost as part of a non-funded cooperative agreement established in FY09 with Filtrexx International. -BMP studies: A manuscript for investigating the utility of duration curves (DCs) for evaluating changes in watershed behavior was begun using runoff data from PA. Source tracking quantification from an OR watershed continues using DCs. Water quality trading: Scientists at the NAEW teamed with scientists at OSU to investigate water-quality trading in the Upper Scioto River basin in Ohio.
1. Several years may be necessary to improve water quality as a result of management changes. Over the years, the federal government has made a significant investment through various conservation programs to implement best management practices (BMPs) to conserve water and soil. To assess the effectiveness of these programs, measurements need to be made to determine how the implementation of BMPs affect water quality and soil loss from the areas receiving the practices. For large watersheds (multiple square miles in area) this is a difficult, expensive, and multiple-year task. Although several years may be involved in assessments on small watersheds (a few acres), such measurements may give valuable insights for responses of BMPs on large watersheds. (Of course, “scaling up” is also a challenge.) Small watersheds were used at the North Appalachian Experimental Watershed near Coshocton, Ohio to measure response time to changes in pasture management practices. Surface runoff was sampled on an event basis; subsurface flow returned to the surface to contribute to continuously flowing streams. With different levels of nitrogen fertility being maintained for multi-year periods, changes in nitrogen movement could be observed downstream at larger watershed sites (multiple acres). The response times indicated that several years are necessary to measure changes in management, and that response times in multiple square miles would be at least as long, probably longer.
2. Rotational out-wintering of beef cows causes less runoff than continuous occupancy but requires more acreage. Winter weather increases the challenges of livestock management, especially if the livestock are not confined. For out-wintering of grazing animals, winter feeding requires different management than at other times of the year. Much feed, usually hay, needs to be brought to the livestock and at a time the weather causes grazing areas to be much more vulnerable to loss of vegetation, compaction, increase surface runoff, and increased soil loss. Although research on the environmental aspects of grazing has addressed a number of concerns, there is very little investigation of the environmental impacts of different systems for out-wintering livestock. Grazing research with beef cattle has been conducted at the North Appalachian Experimental Watershed near Coshocton, Ohio for several years. During these studies, cattle have been kept in one area for the winter and had hay brought to them. In another system the cattle were rotated through fields to eat fall regrowth and then rotated through the same fields again to eat the hay that had been made in them during the summer. Vegetative cover in the continuous wintering area frequently decreased to less than 50% by late winter/early spring. Annual surface runoff was 3 times greater from the continuous wintering than from the rotational wintering, and soil loss was 11 times greater from the continuous wintering than the rotational wintering. April had the highest average monthly runoff and erosion. Cattle were on a given area longer with the continuous wintering than the rotational wintering. So, even though the rotational wintering system was more environmentally sustainable than the continuous wintering system, more land area per cow was necessary.
Owens, L.B., Shipitalo, M.J. 2009. Runoff quality evaluations of continuous and rotational over-wintering systems for beef cows. Agriculture, Ecosystems and Environment. 129(4):482-490.