Identifying the roots of Green Civil War over utility-scale solar energy projects on public lands across the American Southwest

Utility-scale solar energy (USSE) development is an emerging cause of land use change across the American Southwest. Many proposed projects in the region have encountered resistance from environmental groups because of concern about endangered, threatened, and special status species. Projects have also faced resistance from impacted local communities and Native American tribes. This research documents land use conflicts that surfaced during the initial wave of USSE development from 2009 to 2015. The goal is to identify potential roots of land use conflict over renewable energy development, to help explain why there is consistent support for renewables in general, but widespread opposition to projects during the proposal and development stages. The primary data presented include public comments to formal rule-making processes, semi-structured interviews conducted from 2009 to 2013, and various media sources. The paper concludes describing emerging planning frameworks that identify sites for USSE with fewer land use conflicts.     

Influence of Mowing <Emphasis Type="Italic">Artemisia tridentata</Emphasis> ssp. <Emphasis Type="Italic">wyomingensis</Emphasis> on Winter Habitat for Wildlife

Mowing is commonly implemented to Artemisia tridentata ssp. wyomingensis (Beetle & A. Young) S.L. Welsh (Wyoming big sagebrush) plant communities to improve wildlife habitat, increase forage production for livestock, and create fuel breaks for fire suppression. However, information detailing the influence of mowing on winter habitat for wildlife is lacking. This information is crucial because many wildlife species depended on A. tridentata spp. wyomingensis plant communities for winter habitat and consume significant quantities of Artemisia during this time. Furthermore, information is generally limited describing the recovery of A. tridentata spp. wyomingensis to mowing and the impacts of mowing on stand structure. Stand characteristics and Artemisia leaf tissue crude protein (CP), acid detergent fiber (ADF), and neutral detergent fiber (NDF) concentrations were measured in midwinter on 0-, 2-, 4-, and 6-year-old fall-applied mechanical (mowed at 20 cm height) treatments and compared to adjacent untreated (control) areas. Mowing compared to the control decreased Artemisia cover, density, canopy volume, canopy elliptical area, and height (P < 0.05), but all characteristics were recovering (P < 0.05). Mowing A. tridentata spp. wyomingensis plant communities slightly increases the nutritional quality of Artemisia leaves (P < 0.05), but it simultaneously results in up to 20 years of decrease in Artemisia structural characteristics. Because of the large reduction in A. tridentata spp. wyomingensis for potentially 20 years following mowing, mowing should not be applied in Artemisia facultative and obligate wildlife winter habitat. Considering the decline in A. tridentata spp. wyomingensis-dominated landscapes, we caution against mowing these communities.     

Latitudinal variability in spatial genetic structure in the invasive ascidian, Styela plicata

Increases in temperature can shorten planktonic larval durations, so that higher temperatures may reduce dispersal distances for many marine animals. To test this prediction, we first quantified how minimum time to settlement is shortened at higher temperatures for the ascidian Styela plicata. Second, using latitude as a correlate for ocean temperature and spatial genetic structure as a proxy for dispersal, we tested for a negative correlation between latitude and spatial genetic structure within populations, as measured by anonymous DNA markers. Spatial genetic structure was variable among latitudes, with significant structure at low and intermediate latitudes (high and medium temperatures) and there was no genetic structure within high-latitude (low temperature) populations. In addition, we found consistently high genetic diversity across all Australian populations, showing no evidence for recent local bottlenecks associated S. plicata’s history as an invasive species. There was, however, significant genetic differentiation between all populations indicating limited ongoing gene flow.     

Genetic mechanisms of pollution resistance in a marine invertebrate.

Pollution is a common stress in the marine environment and one of today's most powerful agents of selection, yet we have little understanding of how anthropogenic toxicants influence mechanisms of adaptation in marine populations. Due to their life history strategies, marine invertebrates are unable to avoid stress and must adapt to variable environments. We examined the genetic basis of pollution resistance across multiple environments using the marine invertebrate, Styela plicata. Gametes were crossed in a quantitative genetic breeding design to enable partitioning of additive genetic variance across a concentration gradient of a common marine pollutant, copper. Hatching success was scored as a measure of stress resistance in copper concentrations of 0, 75, 150, and 350 microg/L. There was a significant genotype x environment interaction in hatching success across copper concentrations. Further analysis using factor analytic modeling confirmed a significant dimension of across-environment genetic variation where the genetic basis of resistance to stress in the first three environments differed from that in the environment of highest copper concentration. A second genetic dimension further differentiated between the genetic basis of resistance to low and high stress environments. These results suggest that marine organisms use different genetic mechanisms to adapt to different levels of pollution and that the level of genetic variation to adapt to intense pollution stresses may be limited.     

Governing water in federal river basins

Regional Environmental Change -     

Oxidative stress-mediated cardiac mast cell degranulation

Pulmonary mast cell degranulation is a well-characterized response to diesel exhaust exposure. A primary constituent of fossil fuel combustion is sulfur dioxide (SO₂). SO₂ was shown to induce mast cell degranulation in an immortalized cell line secondary to induction of intracellular oxidative stress; however, it is not known whether SO₂-induced oxidative stress directly triggers the activation of cardiac mast cells. Accordingly, this study sought to determine whether Na₂SO₃ induces degranulation of cardiac mast cells, and furthermore whether cardiac mast cell activation may be prevented by inhibition of oxidative stress. To this end, cardiac mast cells were isolated from epicardial surface of the heart and incubated with increasing concentrations of Na₂SO₃ (0, 0.5, or 5 mM). Antioxidant compounds targeting different mechanisms of free radical generation, including ebselen, diphenyleneiodonium (DPI), or α-tocopherol, were incubated with 5 mM of Na₂SO₃ in order to determine their efficacy in preventing mast cell degranulation. Na₂SO₃ induced a significant concentration-dependent histamine release from cardiac mast cells ranging from 8.87% to 18.86%, which was prevented by ebselen. No effect was observed with DPI and α-tocopherol under these conditions. In conclusion, these findings indicate that SO₂ is capable of producing cardiac mast cell degranulation in vitro; however, the variable effectiveness of the three antioxidants evaluated is indicative of a multifactorial mechanism mediating SO₂-induced cardiac mast cell degranulation. The particular effectiveness of ebselen in preventing mast cell degranulation may be related to its multiple mechanisms of preventing oxidative stress.     

Why do female mice mate with multiple males?

Females often show multi-male mating (MMM), but the adaptive functions are unclear. We tested whether female house mice (Mus musculus musculus) show MMM when they can choose their mates without male coercion. We released 32 females into separate enclosures where they could choose to mate with two neighboring males that were restricted to their own territories. We also tested whether females increase MMM when the available males appeared unable to exclude intruders from their territories. To manipulate territorial intrusion, we introduced scent-marked tiles from the neighboring males into males' territories, or we rearranged tiles within males' own territories as a control. Each female was tested in treatment and control conditions and we conducted paternity analyses on the 57 litters produced. We found that 46 % of litters were multiply sired, indicating that multiple paternity is common when females can choose their mates. Intrusion did not increase multiple paternity, though multiple paternity was significantly greater in the first trial when the males were virgins compared to the second trial. Since virgin male mice are highly infanticidal, this finding is consistent with the infanticide avoidance hypothesis. We also found that multiple paternity was higher when competing males showed small differences in their amount of scent marking, suggesting that females reduce MMM when they can detect differences in males' quality. Finally, multiple paternity was associated with increased litter size but only in the intrusion treatment, which suggests that the effect of multiple paternity on offspring number is dependent on male–male interactions.     

Age-related female mating decisions are condition dependent in wolf spiders

Female mating behaviors are known to be sensitive to a variety of individual factors both external and internal to a female; however, mating decisions are likely due to a suite of interacting factors. By independently manipulating female and male diet in the wolf spider Rabidosa rabida and testing females across age groups, we demonstrate that, in addition to its independent effect, female nutritional condition interacts with female age to influence female mating behavior. Overall, high-quantity diet (HD) females were more likely to mate than low-quantity diet (LD) females. Within the LD females, older individuals were more likely to mate than younger individuals, while within HD females, mating probabilities were equal across females of different age classes. With respect to mate choice, only female age influenced the likelihood of mating based on male diet. Young females were choosier as they were more likely to mate with HD males than LD males; in contrast, older females were equally likely to copulate with males of each diet treatment. In addition, the likelihood of pre-sexual cannibalism was dependent on both female and male diet. High-quantity diet females were more likely to cannibalize than LD females, and attacks were directed towards LD males most often. We discuss our results in terms of costs versus benefits of female mate choice.     

Transgenerational plasticity in the sea: context-dependent maternal effects across the life history

Maternal effects can have dramatic influences on the phenotype of offspring. Maternal effects can act as a conduit by which the maternal environment negatively affects offspring fitness, but they can also buffer offspring from environmental change by altering the phenotype of offspring according to local environmental conditions and as such, are a form of transgenerational plasticity. The benefits of maternal effects can be highly context dependent, increasing performance in one life-history stage but reducing it in another. While maternal effects are increasingly well understood in terrestrial systems, studies in the marine environment are typically restricted to a single, early life-history stage. Here, I examine the role of maternal effects across the life history of the bryozoan Bugula neritina. I exposed maternal colonies to a common pollution stress (copper) in the laboratory and then placed them in the field for one week to brood offspring. I then examined the resistance of offspring to copper from toxicant-exposed and toxicant-na?ve mothers and found that offspring from toxicant-exposed mothers were larger, more dispersive, and more resistant to copper stress than offspring from na?ve mothers. However, maternal exposure history had pervasive, negative effects on the post-metamorphic performance (particularly survival) of offspring: offspring from toxicant-exposed mothers had poorer performance after six weeks in the field, especially when facing high levels of intraspecific competition. Maternal experience can have complex effects on offspring phenotype, enhancing performance in one life-history stage while decreasing performance in another. The context-dependent costs and benefits associated with maternally derived pollution resistance may account for why such resistance is induced rather than continually expressed: mothers must balance the benefits of producing pollution-resistant larvae with the costs of producing poorer performing adults (in the absence of pollution).