Preparing the Next Generation of Sustainability Scientists

Graduate programs emerging in universities over recent decades support the advanced study of sustainability issues in complex socio-environmental systems. Constructing the problem-scope to address these issues requires graduate students to integrate across disciplines and synthesize the social and natural dimensions of sustainability. Graduate programs that are designed to foster inter- and transdisciplinary research acknowledge the importance of training students to use integrative research approaches. However, this training is not available in all graduate programs that support integrative research, often requiring students to seek external training opportunities. We present perspectives from a group of doctoral students with diverse disciplinary backgrounds conducting integrative research in universities across the United States who participated in a 10-day, National Science Foundation-funded integrative research training workshop to learn and develop socio-environmental research skills. Following the workshop, students conducted a collaborative autoethnographic study to share pre- and postworkshop research experiences and discuss ways to increase integrative research training opportunities. Results reveal that students, regardless of disciplinary background, face common barriers conducting integrative research that include: (1) lack of exposure to epistemological frameworks and team-science skills, (2) challenges to effectively include stakeholder perspectives in his/her research, and (3) variable levels of committee support to conduct integrative research. To overcome the identified barriers and advance integrative research, students recommend how training opportunities can be embedded within existing graduate programs. Students advocate that both internal and external training opportunities are necessary to support the next generation of sustainability scientists

The neglected role of insulin-like growth factors in the maternal circulation regulating fetal growth

Maternal insulin-like growth factors (IGFs) play a pivotal role in modulating fetal growth via their actions on both the mother and the placenta. Circulating IGFs influence maternal tissue growth and metabolism, thereby regulating nutrient availability for the growth of the conceptus. Maternal IGFs also regulate placental morphogenesis, substrate transport and hormone secretion, all of which influence fetal growth either via indirect effects on maternal substrate availability, or through direct effects on the placenta and its capacity to supply nutrients to the fetus. The extent to which IGFs influence the mother and/or placenta are dependent on the species and maternal factors, including age and nutrition. As altered fetal growth is associated with increased perinatal morbidity and mortality and a greater risk of developing degenerative diseases in adult life, understanding the role of maternal IGFs during pregnancy is essential in order to identify mechanisms underlying altered fetal growth and offspring programming

Collaborative Modeling to Assess Climate Adaptation and Science Information Needs in Snow-fed River Systems

Snow-fed river systems are acutely sensitive to climate change, providing unique case studies to advance an emergent field of socio-hydrology. Climate change alters seasonal snowpack dynamics with warmer temperatures bringing precipitation as rain versus snow, increasing winter flood events, decreasing snowpack accumulation, advancing snowmelt to earlier in the year, shifting peak streamflow, and altering surface water storage and groundwater recharge. Water management based on historical and stationary climate patterns is further challenged under a warmer climate. Participatory research approaches, such as collaborative modeling, are ideally suited in the case study setting and acknowledge the role of local stakeholder knowledge in understanding dynamics between human and water systems.This work presents research as part of a larger collaborative modeling case study underway in the snow-fed Truckee-Carson River System in California and Nevada. Through systematic and iterative engagement with local diverse water managers across the river system, researchers harness local knowledge to assess climate adaptation, identify science information needs, and prioritize hydrologic and operations model simulations accordingly. The following research questions are addressed by this work: 1) How do water supply challenges vary as a function of hydroclimate conditions? 2) How do local adaptation and implementation barriers change coincident with interannual hydroclimate variability? 3) Under a warmer climate and earlier snowmelt regimes, to what extent do locally-identified adaptation strategies enhance water supply? 4) What science information is needed to further support local climate adaptation?Comparison of interviews conducted with key water managers during the 2015 and 2016 consecutive warmer drought years reveals increased drought adaptation efforts that include: enhancing water supply through alternative sources, collecting data to monitor climate impacts, increasing flexibility of existing water management, and fostering improved communication and collaboration among other water managers. Despite drought relief brought by the historic 2017 wet year, these same managers described ongoing drought adaptation efforts to enhance water supply that gained momentum as a result of the improved relationships required to mitigate flood damage. While managers described climate uncertainty as the greatest impediment to their adaptation efforts during consecutive warmer drought years, managers referred to this barrier less often, exemplifying recent climate variability as the “new normal” climate for which they should plan. Instead, managers identified as a critical barrier existing water management practices based on stationary climate patterns and requested researchers simulate locally-identified water management strategies under a warmer climate.To facilitate an evaluation of locally-identified adaptation strategies, researchers simulate Truckee River reservoir reoperation to allow for earlier storage under a warmer climate scenario. Simulation results from an integrated hydrologic and operations model tailored to the Truckee River Basin demonstrate that reservoir reoperation effectively absorbs earlier snowmelt runoff and peak streamflow timing and provides downstream benefits for urban, agricultural, and environmental water users. This work illustrates how collaborative modeling involving local stakeholders and researchers generates information essential for local climate adaptation and also advances applied climate and socio-hydrology research. The collaborative modeling research design can be replicated in other regulated snow-fed river systems characterized by diverse and competing stakeholders managing scarce water supplies under climate change and researchers willing to work closely with stakeholders to investigate strategies in support of local climate adaptation

Black Carbon in Eastern Sierra Nevada Snow Pack

The majority of surface water resources in semi-arid regions originates as mountain snow in higher elevations so detailed understanding of the drivers of snow melt is critical to water management in a changing climate. Black carbon (BC) aerosols emitted during combustion and deposited on permanent and seasonal snow covers decrease reflectance, leading to enhanced snow pack warming, sublimation and melt, but the concentrations, sources, and fate of BC particles in seasonal snow packs are highly uncertain. Measurements of BC, soluble ions, and physical properties in a sequence of snow pits and surface snow samples in the eastern Sierra Nevada mountains excavated during the snow accumulation and melt seasons in 2009 show average concentrations between 1-11 ppb, with surface concentrations as high as 429 ppb. Data analyses and interpretation of results suggests that deposition of BC remains stable as the snow accumulates, but during the melt season, the properties of BC (hydrophilic vs. hydrophobic) influence the fate and transport through the snow pack. The key finding of this study confirmed that BC in melting snow pack behaved independently of soluble impurities, and suggests that radiative forcing at mid-latitudes is significant

Adapting to Variable Water Supply in the Truckee-Carson River System, Western USA

In snow-fed inland river systems in the western United States, water supply depends upon timing, form, and amount of precipitation. In recent years, this region has experienced unprecedented drought conditions due to decreased snowpack, exacerbated by exceptionally warmer winter temperatures averaging 3-4 degrees C above normal. In the snow-fed Truckee-Carson River System, two sets of interviews were conducted as part of a larger collaborative modeling case study with local water managers to examine local adaptation to current drought conditions. A comparative analysis of these primary qualitative data, collected during the fourth and fifth consecutive years of continued warmer drought conditions, identifies shifts in adaptation strategies and emergent adaptation barriers. That is, under continuous exposure to climate stressors, managers shifted their adaptation focus from short-term efforts to manage water demand toward long-term efforts to enhance water supply. Managers described the need to: improve forecasts and scientific assessments of snowmelt timing, groundwater levels, and soil moisture contentincrease flexibility of prior appropriation water allocation rules based on historical snowpack and streamflow timingand foster collaboration and communication among water managers across the river system. While water scarcity and insufficient water delivery infrastructure remain significant impediments in this arid region, climate uncertainty emerged as a barrier surrounding adaptation to variable water supply. Existing prior appropriation based water institutions were also described as an adaptation barrier, meriting objective evaluation to assess how to best modify these historical institutions to support dynamic adaptation to climate-induced water supply variability. This study contributes to a growing body of research that assesses drought adaptation in snow-fed inland river systems, and contributes a unique report concerning how adaptation strategies and barriers encountered by local water managers change over time under continuous exposure to climate stressors. These locally identified adaptation strategies forward a larger collaborative modeling case study by informing alternative water management scenarios simulated through a suite of hydrologic and operations models tailored to this river system

Collaborative Modeling to Assess Drought Resiliency of Snow‐Fed River Dependent Communities in the Western United States: A Case Study in the Truckee‐Carson River System

Assessing the drought resilience of snow‐fed river dependent communities in the arid Western United States has taken on critical importance in response to changing climatic conditions. The process of assessing drought resiliency involves understanding the extent to which snow‐fed dependent communities can absorb the effects of uncertain and variable water supplies while acknowledging and encouraging their capacity for adaptation. Participatory research approaches are particularly well suited to assess resiliency in this context because they rely upon local water managers’ knowledge and perspectives. The research presented here provides measured insight into local water managers’ perceptions of drought resiliency in the Truckee‐Carson River System in northwestern Nevada. These findings are reported in the context of the collaborative modeling research design developed for this case study. The objectives of this study are: (1) to define resiliency and present a rationale for a participatory approach to assess drought resiliency in snow‐fed arid river basins in the Western United States; (2) to outline collaborative modeling as a participatory research design developed for the Truckee‐Carson River System case study area; (3) to describe the development and implementation of a resiliency assessment undertaken to implement this research design; (4) to highlight selected results of the assessment, summarizing interviews with 66 water managers in the case study area; (5) to discuss the use of assessment findings to inform collaborative modeling toward adaptation strategies; and (6) to review lessons learned to date from the collaborative modeling case study and note opportunities for further exploration. According to water managers surveyed, climate change is very important and is mobilizing adaptation strategies that include improvements in communication and coordination with other water managers, monitoring and data collection,and planning. The majority of water managers indicate that future adaptation requires modifying institutionalized water management regimes to allow for temporary water leasing programs, water right stacking on the most productive agricultural lands while fallowing marginal lands,incentivizing water conservation, reducing or eliminating residential landscaping, and recruiting less water intensive industry to the region

Collaborative Modeling to Assess Drought Resiliency of Snow‐Fed River Dependent Communities in the Western United States: A Case Study in the Truckee‐Carson River System

Assessing the drought resilience of snow‐fed river dependent communities in the arid  Western United States has taken on critical importance in response to changing climatic conditions.  The process of assessing drought resiliency involves understanding the extent to which snow‐fed  dependent communities can absorb the effects of uncertain and variable water supplies while  acknowledging and encouraging their capacity for adaptation. Participatory research approaches  are particularly well suited to assess resiliency in this context because they rely upon local water  managers’ knowledge and perspectives. The research presented here provides measured insight  into local water managers’ perceptions of drought resiliency in the Truckee‐Carson River System in  northwestern Nevada. These findings are reported in the context of the collaborative modeling  research design developed for this case study. The objectives of this study are: (1) to define  resiliency and present a rationale for a participatory approach to assess drought resiliency in  snow‐fed arid river basins in the Western United States; (2) to outline collaborative modeling as a  participatory research design developed for the Truckee‐Carson River System case study area; (3)  to  describe  the  development and implementation of a resiliency  assessment  undertaken  to  implement this research design; (4) to highlight selected results of the assessment, summarizing  interviews with 66 water managers in the case study area; (5) to discuss the use of assessment  findings to inform collaborative modeling toward adaptation strategies; and (6) to review lessons  learned  to  date  from  the  collaborative  modeling  case  study  and  note  opportunities  for  further  exploration.  According to  water managers  surveyed,  climate  change  is  very  important  and  is  mobilizing  adaptation  strategies that include improvements in communication and coordination with  other water managers,  monitoring and  data collection,and planning. The majority of water managers  indicate  that future adaptation  requires modifying institutionalized water management regimes to  allow  for  temporary  water  leasing  programs,  water right stacking on the  most  productive  agricultural lands while  fallowing  marginal  lands,incentivizing water conservation, reducing or  eliminating  residential  landscaping, and recruiting less water intensive industry to the region

Long-term, but not short-term, treatment with somatotropin during pregnancy in underfed pigs increases the body size of progeny at birth

Treatment of pigs with porcine ST (pST) in early to mid-pregnancy increases body weight and length of their fetuses by mid-pregnancy, but this increased weight may not persist to birth. We investigated the effects of short- (25 d) and long-term (75 d) treatment with pST, and interactions between long-term pST treatment and crude protein content of diet, in restricted-fed gilts. In both experiments, Large White x Landrace gilts were bred at first estrus to Large White x Duroc boars and allowed to farrow naturally. In the first experiment, gilts were fed 1.8 kg/d of a diet containing 13.5 MJ DE/kg of DM and 15.05% CP (as-fed basis) throughout pregnancy, and were injected daily with 0, 2, or 4 mg pST from d 25 to 50 of pregnancy. Maternal treatment with pST from d 25 to 50 of pregnancy did not affect the number of piglets born per litter or progeny size at birth. In the second experiment, gilts were injected daily with 0 or 2 mg of pST and fed 2.2 kg/d of a diet containing 14.5 MJ DE/kg and either (as-fed basis) 16.6% (0.81% lysine) or 22.2% CP (1.16% lysine) from d 25 to 100 of pregnancy. All gilts were then fed 3.0 kg/d of the lower protein diet from d 100 of pregnancy to farrowing. Treatment with 2 mg pST/d from d 25 to 100 of pregnancy increased live weight of all gilts during the treatment period (P = 0.016), but the change in maternal live weight from d 25 to 100 of pregnancy was only increased (P = 0.001) by pST in gilts fed the higher protein diet. Live weight of gilts 1 d after farrowing was increased by pST treatment (P = 0.007), but was not altered by protein content of diet during pregnancy. In gilts fed the lower protein diet, but not in those fed the higher protein diet, pST treatment decreased maternal backfat depth during treatment (P < 0.020) and 1 d after farrowing (P = 0.002). Treatment with pST during pregnancy did not affect the number of piglets born per litter but independently increased body weight by 11.6% (P < 0.001) and length by 3.4% (P = 0.005) of progeny at birth and decreased (P < 0.01) the negative effect of litter size on body weight at birth. We conclude that in feed-restricted gilts, fetal weight gains in response to 25 d of pST treatment before mid-pregnancy are not maintained to term but that treatment with pST during most of pregnancy increases progeny size at birth and reduces maternal constraint of fetal growth.K. L. Gatford, J. M. Boyce, K. Blackmore, R. J. Smits, R. G. Campbell, and P. C. Owen