Large-Scale Land Development, Fugitive Dust, and Increased Coccidioidomycosis Incidence in the Antelope Valley of California, 1999-2014.

Ongoing large-scale land development for renewable energy projects in the Antelope Valley, located in the Western Mojave Desert, has been blamed for increased fugitive dust emissions and coccidioidomycosis incidence among the general public in recent years. Soil samples were collected at six sites that were destined for solar farm construction and were analyzed for the presence of the soil-borne fungal pathogen Coccidioides immitis which is endemic to many areas of central and southern California. We used a modified culture-independent nested PCR approach to identify the pathogen in all soil samples and also compared the sampling sites in regard to soil physical and chemical parameters, degree of disturbance, and vegetation. Our results indicated the presence of C. immitis at four of the six sites, predominantly in non-disturbed soils of the Pond-Oban complex, which are characterized by an elevated pH and salt bush communities, but also in grassland characterized by different soil parameters and covered with native and non-native annuals. Overall, we were able to detect the pathogen in 40% of the soil samples (n = 42). Incidence of coccidioidomycosis in the Antelope Valley was positively correlated with land use and particulate matter in the air (PM10) (Pearson correlation coefficient >0.5). With the predicted population growth and ongoing large-scale disturbance of soil in the Antelope Valley in coming years, incidence of coccidioidomycosis will likely further increase if policy makers and land developers continue to ignore the risk of grading land without implementing long-term dust mitigation plans in Environmental Impact Reports.

A comparison of fluorescence in two sympatric scorpion species.

In order to test the feasibility of scorpion fluorescence as an indicator of gender and/or species identity, a comparison of the fluorescence spectra between genders across two sympatric species of scorpions (Vaejovis confusus Stahnke 1940 and Paruroctonus shulovi Williams 1970) was conducted. Each spectrum was represented in a simple multivariate analysis by its peak wavelength and width at 90% of peak intensity. No difference between genders was found, but a statistically significant difference between species was detected. The potential of fluorescence as a basis for species recognition based on this difference is discussed in the context of what is known about scorpion vision and discriminatory abilities.