Assessment of plant availability and environmental risk of biosolids-phosphorus in a U.S. Midwest Corn-Belt Soil.

A field experiment was conducted from 2005 to 2008 in Fulton County, Western Illinois with biosolids from conventional wastewater treatment applied as corn fertilizer in a series of P rates (0, 163, 325, 488, 650 kg P ha(-1)) along with commercial P fertilizer - triple superphosphate P (TSP) as reference to assess biosolids-P plant availability and potential loss to waterbodies through runoff. Air-dried biosolids and TSP were incorporated into surface soil at end of 2005, and corn (Zea mays) was planted for three consecutive years (2006-2008). Concentrations of soil extractable P except for Mehlich-3 P were always lower in the biosolids than TSP treatments at the same P rates. The soil potentially available P in water extractable P (WEP) and Olsen P derived from biosolids-P estimated by the exponential depletion model was 2-4% and 15-24% of total P in the applied biosolids, respectively. The residence time of biosolids-induced WEP and Olsen P in Midwest soil under annual corn cropping was 5 and 2 years, respectively. Corn tissue analysis showed lower increase in P concentration by biosolids-P than TSP. The elevation rate of soluble reactive P (SRP) concentration in simulated runoff was less by biosolids than TSP. Based on the data in this study, the plant availability and environmental risk of biosolids-P are lower than those of TSP in the Midwest soil, thus use of biosolids as P nutrient for corn would not cause a major impairment to water sources even P applied through biosolids was not completely used by annual crop.

Restoring Ecosystem Function in Degraded Urban Soil Using Biosolids, Biosolids Blend, and Compost.

Many soils at former industrial sites are degraded. The objective of this research was to determine the ability of compost, biosolids, and biosolids blends to improve soil ecosystem function with minimal potential impact to surface water. Treatments rototilled into the top 12.5 cm of soil were biosolids at 202 Mg ha; biosolids at 404 Mg ha; compost at 137 Mg ha; or a blend consisting of biosolids applied at 202 Mg ha, drinking water treatment residual, and biochar. Rainfall runoff from experimental plots was collected for 3 yr. One year after soil amendments were incorporated, a native seed mix containing grasses, legumes, and forbs was planted. Soil amendments improved soil quality and nutrient pools, established a dense and high-quality vegetative cover, and improved earthworm reproductive measures. Amendments increased soil enzymatic activities that support soil function. Biosolids treatments increased the Shannon-Weaver Diversity Index for grasses. For the forbs group, control plots had the lowest diversity index and the biosolids blend had the highest diversity index. Biosolids and compost increased the number of earthworm juveniles. In general, biosolids outperformed compost. Biosolids increased N and P in rainfall runoff more than compost before vegetation was established. Several microconstituents (i.e., pharmaceutical and personal care products) were detected in runoff water but at concentrations below the probable no-effect levels and therefore should pose little impact to the aquatic environment. Future restoration design should ensure that runoff control measures are used to control sediment loss from the restored sites at least until vegetation is established.

Soil carbon sequestration resulting from long-term application of biosolids for land reclamation.

Investigations on the impact of application of biosolids for land reclamation on C sequestration in soil were conducted at Fulton County, Illinois, where 41 fields (3.6-66 ha) received biosolids at a cumulative loading rate from 455 to 1654 dry Mg ha(-1) for 8 to 23 yr in rotation from 1972 to 2004. The fields were cropped with corn, wheat, and sorghum and also with soybean and grass or fallowed. Soil organic carbon (SOC) increased rapidly with the application of biosolids, whereas it fluctuated slightly in fertilizer controls. The peak SOC in the 0- to 15-cm depth of biosolids-amended fields ranged from 4 to 7% and was greater at higher rates of biosolids. In fields where biosolids application ceased for 22 yr, SOC was still much higher than the initial levels. Over the 34-yr reclamation, the mean net soil C sequestration was 1.73 (0.54-3.05) Mg C ha(-1) yr(-1) in biosolids-amended fields as compared with -0.07 to 0.17 Mg C ha(-1) yr(-1) in fertilizer controls, demonstrating a high potential of soil C sequestration by the land application of biosolids. Soil C sequestration was significantly correlated with the biosolids application rate, and the equation can be expressed as y = 0.064x - 0.11, in which y is the annual net soil C sequestration (Mg C ha(-1) yr(-1)), and x is annual biosolids application in dry weight (Mg ha(-1) yr(-1)). Our results indicate that biosolids applications can turn Midwest Corn Belt soils from current C-neutral to C-sink. A method for calculating SOC stock under conditions in which surface soil layer depth and mass changes is also described.

The DNA mismatch repair enzyme PMS1 is a myositis-specific autoantigen.

OBJECTIVE: The specificity of the autoantibody response in different autoimmune diseases makes autoantibodies useful for diagnostic purposes. It also focuses attention on tissue- and event-specific circumstances that may select unique molecules for an autoimmune response in specific diseases. Defining additional phenotype-specific autoantibodies may identify such circumstances. This study was undertaken to investigate the disease specificity of PMS1, an autoantigen previously identified in some sera from patients with myositis. METHODS: We used immunoprecipitation analysis to determine the frequency of autoantibodies to PMS1 in sera from patients with myositis, systemic lupus erythematosus, or scleroderma and from healthy controls. Additional antigens recognized by PMS1-positive sera were further characterized in terms of their susceptibility to cleavage by apoptotic proteases. RESULTS: PMS1, a DNA mismatch repair enzyme, was identified as a myositis-specific autoantigen. Autoantibodies to PMS1 were found in 4 of 53 patients with autoimmune myositis (7.5%), but in no sera from 94 patients with other systemic autoimmune diseases (P = 0.016). Additional mismatch repair enzymes (PMS2, MLH1) were targeted, apparently independently. Sera recognizing PMS1 also recognized several other proteins involved in DNA repair and remodeling, including poly(ADP-ribose) polymerase, DNA-dependent protein kinase, and Mi-2. All of these autoantigens were efficiently cleaved by granzyme B, generating unique fragments not observed during other forms of cell death. CONCLUSION: PMS1 autoantibodies are myositis specific. The striking correlation between an immune response to a group of granzyme B substrates (functioning in DNA repair and remodeling) and the myositis phenotype strongly implies that tissue- and event-specific biochemical events play a role in selecting these molecules for an autoimmune response. Understanding the role of granzyme B cleavage in this response is an important priority.