Brad C. Joern

Bio: Brad C. Joern is an academic researcher from University College West. The author has contributed to research in topics: Manure & Phosphorus. The author has an hindex of 3, co-authored 5 publications receiving 1147 citations.

Phosphorus loss in agricultural drainage: historical perspective and current research

Abstract: The importance of P originating from agricultural sources to the nonpoint source pollution of surface waters has been an environmental issue for decades because of the well-known role of P in eutrophication. Most previous research and nonpoint source control efforts have emphasized P losses by surface erosion and runoff because of the relative immobility of P in soils. Consequently, P leaching and losses of P via subsurface runoff have rarely heen considered important pathways for the movement of agricultural P to surface waters. However, there are situations where environmentally significant export of P in agricultural drainage has occurred (e.g., deep sandy soils, high organic matter soils, or soils with high soil P concentrations from long-term overfertilization andlor excessive use of organic wastes). In this paper we review research on P leaching and export in subsurface runoff and present overviews of ongoing research in the Atlantic Coastal Plain of the USA (Delaware), the midwestern USA (Indiana), and eastern Canada (Quehec). Our objectives are to illustrate the importance of agricultural drainage to nonpoint source pollution of surface waters and to emphasize the need for soil and water conservation practices that can minimize P losses in suhsurface runoff.

Phytase, High‐Available‐Phosphorus Corn, and Storage Effects on Phosphorus Levels in Pig Excreta

Abstract: Phosphorus-based land application limits for manure have increased the importance of optimizing diet P management and accurately characterizing the bioavailability of manure P. We examined the effects of pig (Sus scrofa) diets formulated with high-available-P corn and phytase on P levels in excreta and slurry stored for 30, 60, 90, 120, and 150 d. Twenty-four pigs (approximately 14 kg each) were fed one of four low-P diets: (i) normal corn, no phytase (control); (ii) normal corn with 600 phytase units kg(-1) (PHY); (iii) high-available-P corn, no phytase (HAP); and (iv) high-available-P corn with 600 phytase units kg(-1) (HAP + PHY). Fresh fecal and stored slurry dry matter (DM) was analyzed for total phosphorus (TP), dissolved molybdate-reactive phosphorus (DRP), dissolved organic phosphorus (DOP), acid-soluble reactive phosphorus (ASRP), acid-soluble organic phosphorus (ASOP), and phytate phosphorus (PAP). The PHY, HAP, and HAP + PHY diets significantly (alpha = 0.05) decreased fecal TP 19, 17, and 40%, respectively, compared with the control. Dissolved reactive P was 36% lower in the HAP + PHY diet compared with the other diets. Relative fractions (percent of TP) of DRP, DOP, ASOP, and PAP in slurry generally decreased with storage time up to 150 d, with the largest decreases occurring within 60 to 90 d. Diet-induced differences in relative fractions of DRP, DOP, ASRP, and PAP were significant when averaged across storage times, simulating a mixed-age slurry. Relative fractions of DRP in simulated mixed-age slurries were higher in HAP and HAP + PHY diets, indicating that diet may affect P losses under certain P-based application scenarios.

Using Linear Programming to Minimize Manure Storage and Application Costs in Pork Production

Abstract: Various computer models have been developed to assist producers in planning manure and nutrient management programs. None of these models incorporates fixed costs associated with manure storage, hauling, and application. Current methods for calculating manure application rates require information such as nutrient content in manure, availability of nutrients for use as a fertilizer, and loss factors for different storage and application methods. The objective of this study was to develop a linear programming model that incorporates economic data on fixed and variable costs that can be linked to existing manure management computer models. An example with respect to swine (Sus scrofa) production is presented for various enterprise systems. As the size of the swine enterprise becomes greater than 150 sows, earthen lagoon storage and irrigation application becomes the optimal least cost method. Least cost storage and application costs for the 1200 sow operation was 63% of the least cost solution for the 150 sow operation. Within the same storage and application system, the 1200 sow operation had 77% of the per pig costs for a 300 sow operation. For enterprises with fewer sows, deep pit storage and injection application is the least cost choice.

SOIL FERTILITY & PLANT NUTRITION Potassium Fertility and Terrain Attributes in a Fragiudalf Drainage Catena

Abstract: Site-specifi c management of soil fertility has been based on soil sampling in grid patterns or within soil mapping units without taking full advantage of terrain-soil relationships. The goal of this study was to determine whether terrain attributes relate signifi cantly to soil K availability. The topographic wetness index (TWI), a terrain attribute that comprises the upstream contributing area and the slope for a portion of land, relates to soil wetness. We evaluated Mehlich-3 K (M3K), plant-available nonexchangeable K (PANK) with a modi- fi ed tetraphenylboron extraction, effective cation exchange capacity (ECEC), and other soil variables from soil samples taken at three depths, and terrain attributes in a 3.6-ha farmed site in the Cincinnati catena, a major toposequence in the Muscatatuck Uplands region of Indiana. The PANK and M3K were signifi cantly (P < 0.0001 and P < 0.05, respectively) related to TWI and relative elevation in models with anisotropic spatial autocorrelation vari- ance estimates in three dimensions (latitude, longitude, and soil depth). The PANK and M3K increased with decreasing TWI in the following drainage class order: poorly < some- what poorly < moderately well drained. The M3K decreased with soil depth, while PANK increased. The PANK/M3K ratio was signifi cantly higher in the poorly drained soils than in the moderately well-drained soils, implying greater mobility or weathering of K in wetter soils. The ECEC also related strongly to terrain attributes (P < 0.0001 for relative elevation, TWI, and interaction effects). Possible mechanisms include lateral downslope lessivage and K leaching. Terrain attributes can aid in soil K fertility evaluations on the Cincinnati catena because they relate well to soil K fertility measurements.

Phosphorus and nitrogen loading depths in fluvial sediments following manure spill simulations

Abstract: Armstrong, S. D., Smith, D. R., Owens, P. R., Joern, B. C., Leytem, A. B., Huang, C.H. and Adeola, L. 2011. Phosphorus and nitrogen loading depth in fluvial sediments following manure spill simulations. Can. J. Soil Sci. 91: 427-436. The depth of nitrogen (N) and phosphorus (P) loading in fluvial sediments following a manure spill has not been documented. Thus, the objectives of this study were: (i) to determine the depth of N and P enrichment as a result of a manure spill under base flow conditions using fluvarium techniques and (ii) to evaluate the impact of sediment particle size distribution on N and P enrichment depth. Manure spills were simulated using stream simulators and ditch sediments collected from agricultural drainage ditches. During the manure spill simulation, the P sorption capacity of all sediments exponentially decreased with time and the NH4-N sorption capacity remained constant with time. The P and NH4-N loading in all sediments were observed to the depth of 2 cm, but were most concen...

Eutrophication of freshwater and coastal marine ecosystems a global problem

Abstract: Humans now strongly influence almost every major aquatic ecosystem, and their activities have dramatically altered the fluxes of growth-limiting nutrients from the landscape to receiving waters. Unfortunately, these nutrient inputs have had profound negative effects upon the quality of surface waters worldwide. This review examines how eutrophication influences the biomass and species composition of algae in both freshwater and costal marine systems. An overview of recent advances in algae-related eutrophication research is presented. In freshwater systems, a summary is presented for lakes and reservoirs; streams and rivers; and wetlands. A brief summary is also presented for estuarine and coastal marine ecosystems. Eutrophication causes predictable increases in the biomass of algae in lakes and reservoirs; streams and rivers; wetlands; and coastal marine ecosystems. As in lakes, the response of suspended algae in large rivers to changes in nutrient loading may be hysteretic in some cases. The inhibitory effects of high concentrations of inorganic suspended solids on algal growth, which can be very evident in many reservoirs receiving high inputs of suspended soils, also potentially may occur in turbid rivers. Consistent and predictable eutrophication-caused increases in cyanobacterial dominance of phytoplankton have been reported worldwide for natural lakes, and similar trends are reported here both for phytoplankton in turbid reservoirs, and for suspended algae in a large river. A remarkable unity is evident in the global response of algal biomass to nitrogen and phosphorus availability in lakes and reservoirs; wetlands; streams and rivers; and coastal marine waters. The species composition of algal communities inhabiting the water column appears to respond similarly to nutrient loading, whether in lakes, reservoirs, or rivers. As is true of freshwater ecosystems, the recent literature suggests that coastal marine ecosystems will respond positively to nutrient loading control efforts. Our understanding of freshwater eutrophication and its effects on algal-related water quality is strong and is advancing rapidly. However, our understanding of the effects of eutrophication on estuarine and coastal marine ecosystems is much more limited, and this gap represents an important future research need. Although coastal systems can be hydrologically complex, the biomass of marine phytoplankton nonetheless appears to respond sensitively and predictably to changes in the external supplies of nitrogen and phosphorus. These responses suggest that efforts to manage nutrient inputs to the seas will result in significant improvements in coastal zone water quality. Additional new efforts should be made to develop models that quantitatively link ecosystem-level responses to nutrient loading in both freshwater and marine systems.

Human Impact on Erodable Phosphorus and Eutrophication: A Global Perspective

Abstract: Human actions—mining phosphorus (P) and transporting it in fertilizers, animal feeds, agricultural crops, and other products—are altering the global P cycle, causing P to accumulate in some of the world’s soil. Increasing P levels in the soil elevate the potential P runoff to aquatic ecosystems (Fluck et al. 1992, NRC 1993, USEPA 1996). Using a global budget approach, we estimate the increase in net P storage in terrestrial and freshwater ecosystems to be at least 75% greater than preindustrial levels of storage. We calculated an agricultural mass balance (budget), which indicated that a large portion of this P accumulation occurs in agricultural soils. Separate P budgets of the agricultural areas of developing and developed countries show that the rate of P accumulation is decreasing in developed nations but increasing in developing nations.

Phosphorus legacy: overcoming the effects of past management practices to mitigate future water quality impairment.

Abstract: The water quality response to implementation of conservation measures across watersheds has been slower and smaller than expected. This has led many to question the efficacy of these measures and to call for stricter land and nutrient management strategies. In many cases, this limited response has been due to the legacies of past management activities, where sinks and stores of P along the land-freshwater continuum mask the effects of reductions in edge-of-field losses of P. Accounting for legacy P along this continuum is important to correctly apportion sources and to develop successful watershed remediation. In this study, we examined the drivers of legacy P at the watershed scale, specifically in relation to the physical cascades and biogeochemical spirals of P along the continuum from soils to rivers and lakes and via surface and subsurface flow pathways. Terrestrial P legacies encompass prior nutrient and land management activities that have built up soil P to levels that exceed crop requirements and modified the connectivity between terrestrial P sources and fluvial transport. River and lake P legacies encompass a range of processes that control retention and remobilization of P, and these are linked to water and sediment residence times. We provide case studies that highlight the major processes and varying timescales across which legacy P continues to contribute P to receiving waters and undermine restoration efforts, and we discuss how these P legacies could be managed in future conservation programs.

Groundwater recharge and agricultural contamination

Abstract: Agriculture has had direct and indirect effects on the rates and compositions of groundwater recharge and aquifer biogeochemistry Direct effects include dis- solution and transport of excess quantities of fertilizers and associated materials and hydrologic alterations relat- ed to irrigation and drainage Some indirect effects in- clude changes in water-rock reactions in soils and aqui- fers caused by increased concentrations of dissolved oxi- dants, protons, and major ions Agricultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO 3 - , N 2 , Cl, SO 4 2- , H + , P, C, K, Mg, Ca, Sr, Ba, Ra, and As, as well as a wide variety of pesti- cides and other organic compounds For reactive con- taminants like NO 3 - , a combination of chemical, isoto- pic, and environmental-tracer analytical approaches might be required to resolve changing inputs from subse- quent alterations as causes of concentration gradients in groundwater Groundwater records derived from multi- component hydrostratigraphic data can be used to quan- tify recharge rates and residence times of water and dis- solved contaminants, document past variations in re- charging contaminant loads, and identify natural contam- inant-remediation processes These data indicate that many of the world's surficial aquifers contain transient records of changing agricultural contamination from the last half of the 20th century The transient agricultural groundwater signal has important implications for long- term trends and spatial heterogeneity in discharge

Agricultural Phosphorus and Eutrophication: A Symposium Overview

Abstract: Phosphorus in runoff from agricultural land is an important component of nonpoint-source pollution and can accelerate eutrophication of lakes and streams. Long-term land application of P as fertilizer and animal wastes has resulted in elevated levels of soil P in many locations in the USA. Problems with soils high in P are often aggravated by the proximity of many of these areas to P-sensitive water bodies, such as the Great Lakes, Chesapeake and Delaware Bays, Lake Okeechobee, and the Everglades. This paper provides a brief overview of the issues and options related to management of agricultural P that were discussed at a special symposium titled, “Agricultural Phosphorus and Eutrophication,” held at the November 1996 American Society of Agronomy annual meetings. Topics discussed at the symposium and reviewed here included the role of P in eutrophication; identification of P-sensitive water bodies; P transport mechanisms; chemical forms and fate of P; identification of P source areas; modeling of P transport; water quality criteria; and management of soil and manure P, off-farm P inputs, and P transport processes.