Audit report on the Iowa Legislature for the year ended June 30, 2008

Audit report on the Iowa Legislature for the year ended June 30, 2008

Audit report on the Iowa Petroleum Underground Storage Tank Board (UST Board) for the year ended June 30, 2008

Audit report on the Iowa Petroleum Underground Storage Tank Board (UST Board) for the year ended June 30, 2008

Audit report on the City of Robins, Iowa for the year ended June 30, 2008

Audit report on the City of Robins, Iowa for the year ended June 30, 2008

Sampling strategies for tropical forest nutrient cycling studies: a case study in São Paulo, Brazil

The precise sampling of soil, biological or micro climatic attributes in tropical forests, which are characterized by a high diversity of species and complex spatial variability, is a difficult task. We found few basic studies to guide sampling procedures. The objective of this study was to define a sampling strategy and data analysis for some parameters frequently used in nutrient cycling studies, i. e., litter amount, total nutrient amounts in litter and its composition (Ca, Mg, Κ, Ν and P), and soil attributes at three depths (organic matter, Ρ content, cation exchange capacity and base saturation). A natural remnant forest in the West of São Paulo State (Brazil) was selected as study area and samples were collected in July, 1989. The total amount of litter and its total nutrient amounts had a high spatial independent variance. Conversely, the variance of litter composition was lower and the spatial dependency was peculiar to each nutrient. The sampling strategy for the estimation of litter amounts and the amount of nutrient in litter should be different than the sampling strategy for nutrient composition. For the estimation of litter amounts and the amount of nutrients in litter (related to quantity) a large number of randomly distributed determinations are needed. Otherwise, for the estimation of litter nutrient composition (related to quality) a smaller amount of spatially located samples should be analyzed. The determination of sampling for soil attributes differed according to the depth. Overall, surface samples (0-5 cm) showed high short distance spatial dependent variance, whereas, subsurface samples exhibited spatial dependency in longer distances. Short transects with sampling interval of 5-10 m are recommended for surface sampling. Subsurface samples must also be spatially located, but with transects or grids with longer distances between sampling points over the entire area. Composite soil samples would not provide a complete understanding of the relation between soil properties and surface dynamic processes or landscape aspects. Precise distribution of Ρ was difficult to estimate.

Audit report on the City of Central City, Iowa for the year ended June 30, 2008

Audit report on the City of Central City, Iowa for the year ended June 30, 2008

Which is the optimal sampling strategy for habitat suitability modelling

Designing an efficient sampling strategy is of crucial importance for habitat suitability modelling. This paper compares four such strategies, namely, 'random', 'regular', 'proportional-stratified' and 'equal -stratified'- to investigate (1) how they affect prediction accuracy and (2) how sensitive they are to sample size. In order to compare them, a virtual species approach (Ecol. Model. 145 (2001) 111) in a real landscape, based on reliable data, was chosen. The distribution of the virtual species was sampled 300 times using each of the four strategies in four sample sizes. The sampled data were then fed into a GLM to make two types of prediction: (1) habitat suitability and (2) presence/ absence. Comparing the predictions to the known distribution of the virtual species allows model accuracy to be assessed. Habitat suitability predictions were assessed by Pearson's correlation coefficient and presence/absence predictions by Cohen's K agreement coefficient. The results show the 'regular' and 'equal-stratified' sampling strategies to be the most accurate and most robust. We propose the following characteristics to improve sample design: (1) increase sample size, (2) prefer systematic to random sampling and (3) include environmental information in the design'

Audit report on the City of Maxwell, Iowa for the year ended June 30, 2008

Audit report on the City of Maxwell, Iowa for the year ended June 30, 2008

Audit report on the City of Anita, Iowa for the year ended June 30, 2008

Audit report on the City of Anita, Iowa for the year ended June 30, 2008

Audit report on the Iowa Turkey Marketing Council for the years ended December 31, 2008 and 2007

Audit report on the Iowa Turkey Marketing Council for the years ended December 31, 2008 and 2007

Audit report of the Department of Corrections for the year ended June 30, 2008

Audit report of the Department of Corrections for the year ended June 30, 2008

Audit report on Delaware Township, located in Polk County, Iowa, for the year ended June 30, 2008

Audit report on Delaware Township, located in Polk County, Iowa, for the year ended June 30, 2008

Audit report on the Iowa Department of Transportation for the year ended June 30, 2008

Audit report on the Iowa Department of Transportation for the year ended June 30, 2008

Audit report of Iowa State Prison Industries – Farms for the year ended June 30, 2008

Audit report of Iowa State Prison Industries – Farms for the year ended June 30, 2008