18 research outputs found
Impacts of Habitat Fragmentation on Northern Bobwhites in the Gulf Coast Prairie Landscape Conservation Cooperative
The northern bobwhite (Colinus virginianus) has experienced range wide declines over the last several decades, primarily due to loss and fragmentation of habitat. As populations decline, there is a need for understanding factors that impact bobwhite population persistence at local and regional spatial scales. Our goal was to assess changes in land use and their relationship to bobwhite declines at 3 different spatial scales (region, county, and home range) in Texas, Oklahoma, and Louisiana. We used North American Breeding Bird Survey (BBS) data from 1974-2014 to create abundance maps and trends. At the regional scale, we compared bobwhite abundance with road density (2000, 2010), human population (1970-2010), and land use (1974-2012). We then used the BBS data to identify counties with stable and declining bobwhite abundance, and then compared bobwhite abundance to land use at metapopulation (800-9600 ha) and home range scales (15 ha). Bobwhite populations decreased from 45.93 ± 1.01 birds/count in 1970 to 11.55 ± 0.64 birds/count in 2012. as road density and human population increased. Pasture and other land increased, woodland was relatively stable, and cropland decreased in 2012. At the metapopulation level, declining populations had higher road density, more edge and patch area for pasture, and larger patches of cropland compared to stable populations. At the home range scale, declining populations had significantly fewer, and smaller, woody patches, more herbaceous habitat, and less bare ground. This study demonstrates that while on a small scale managers can provide woody cover and reduce cropland effects to support stable populations, the large-scale drivers of bobwhite decline, namely human population growth and the resulting loss of habitat, will be critical to quail management in the future
Increased Risk of Autism Development in Children Whose Mothers Experienced Birth Complications or Received Labor and Delivery Drugs
Autism spectrum disorder (ASD) is a perplexing and pervasive developmental disorder characterized by social difficulties, communicative deficits, and repetitive behavior. The increased rate of ASD diagnosis has raised questions concerning the genetic and environmental factors contributing to the development of this disorder; meanwhile, the cause of ASD remains unknown. This study surveyed mothers of ASD and non-ASD children to determine possible effects of labor and delivery (L&D) drugs on the development of ASD. The survey was administered to mothers; however, the results were analyzed by child, as the study focused on the development of autism. Furthermore, an independent ASD dataset from the Southwest Autism Research and Resource Center was analyzed and compared. Indeed, L&D drugs are associated with ASD ( p = .039). Moreover, the Southwest Autism Research and Resource Center dataset shows that the labor induction drug, Pitocin, is significantly associated with ASD ( p = .004). We also observed a synergistic effect between administrations of L&D drugs and experiencing a birth complication, in which both obstetrics factors occurring together increased the likelihood of the fetus developing ASD later in life ( p = .0003). The present study shows the possible effects of L&D drugs, such as Pitocin labor-inducing and analgesic drugs, on children and ASD
The Interactive Effects of Drought and Fire on Soil Microbial Communities in a Semi-Arid Savanna
Impacts of Habitat Fragmentation on Northern Bobwhites in the Gulf Coast Prairie Landscape Conservation Cooperative
Screening of bacteria for the suppression of Botrytis cinerea and Rhizoctonia solani on lettuce (Lactuca sativa) using leaf disc bioassays
Extreme drought impacts have been underestimated in grasslands and shrublands globally.
Climate change is increasing the frequency and severity of short-term (~1 y) drought events-the most common duration of drought-globally. Yet the impact of this intensification of drought on ecosystem functioning remains poorly resolved. This is due in part to the widely disparate approaches ecologists have employed to study drought, variation in the severity and duration of drought studied, and differences among ecosystems in vegetation, edaphic and climatic attributes that can mediate drought impacts. To overcome these problems and better identify the factors that modulate drought responses, we used a coordinated distributed experiment to quantify the impact of short-term drought on grassland and shrubland ecosystems. With a standardized approach, we imposed ~a single year of drought at 100 sites on six continents. Here we show that loss of a foundational ecosystem function-aboveground net primary production (ANPP)-was 60% greater at sites that experienced statistically extreme drought (1-in-100-y event) vs. those sites where drought was nominal (historically more common) in magnitude (35% vs. 21%, respectively). This reduction in a key carbon cycle process with a single year of extreme drought greatly exceeds previously reported losses for grasslands and shrublands. Our global experiment also revealed high variability in drought response but that relative reductions in ANPP were greater in drier ecosystems and those with fewer plant species. Overall, our results demonstrate with unprecedented rigor that the global impacts of projected increases in drought severity have been significantly underestimated and that drier and less diverse sites are likely to be most vulnerable to extreme drought
