Effect of gender on sap-flux-scaled transpiration in a dominant riparian tree species: Box elder (Acer negundo)

Journal ArticleAcer negundo is a dioecious riparian tree species with a spatial segregation of the sexes along soil moisture gradients. Females are typically more common in wet sites along streams (typically F/M = 1.6), whereas males are more common in drier sites away from streams (typically F/M = 0.6). Spatial segregation between sexes may develop because of the higher reproductive cost in females compared to males. Copyright [year] American Geophysical Union. Reproduced by permission of American Geophysical Union. Further reproduction or electronic distribution is not permitted

Transpiration and hydraulic strategies in a piñon-juniper woodland

Journal ArticleAnthropogenic climate change is likely to alter the patterns of moisture availability globally. The consequences of these changes on species distributions and ecosystem function are largely unknown, but possibly predictable based on key ecophysiological differences among currently coexisting species. In this study, we examined the environmental and biological controls on transpiration from a piñon juniper (Pinus edulis- Juniperus osteosperma) woodland in southern Utah, USA

Carbon and nitrogen allocation to male and female reproduction in Rocky Mountain Douglas-fir (Pseudotsuga menziesii var. glauca, Pinaceae)

Journal ArticleWe measured carbon (respiration, photosynthesis, and production) and nitrogen allocation to male and female cones of Rocky Mountain Douglas-fir (Pseudotsuga menziesii var. glauca) to quantify gender-specific: (1) resource allocation to reproduction, and (2) contribution to carbon costs of reproduction via photosynthesis

Ecophysiology of riparian cottonwood and willow before, during, and after two years of soil water removal

Journal ArticleRiparian cottonwood/willow forest assemblages are highly valued in the southwestern United States for their wildlife habitat, biodiversity, and watershed protection. Yet these forests are under considerable threat from climate change impacts on water resources and land-use activities to support human enterprise. Stream diversions, groundwater pumping, and extended drought have resulted in the decline of cottonwood/willow forests along many riparian corridors in the Southwest and, in many cases, the replacement of these forests with less desirable invasive shrubs and trees. Nevertheless, ecophysiological responses of cottonwood and willow, along with associated ecohydrological feedbacks of soil water depletion, are not well understood. Ecophysiological processes of mature Fremont cottonwood and coyote willow stands were examined over four consecutive growing seasons (2004-2007) near Salt Lake City, Utah, USA. The tree stands occurred near the inlet of a reservoir that was drained in the spring of 2005 and remained empty until mid-summer of 2006, effectively removing the primary water source for most of two growing seasons. Stem sap flux density (Js) in cottonwood was highly correlated with volumetric soil moisture (h) in the upper 60 cm and decreased sevenfold as soil moisture dropped from 12% to 7% after the reservoir was drained. Conversely, Js in willow was marginally correlated with h and decreased by only 25% during the same period. Opposite patterns emerged during the following growing season: willow had a lower whole-plant conductance (kt) in June and higher leaf carbon isotope ratios (d13C) than cottonwood in August, whereas kt and d13C were otherwise similar between species. Water relations in both species recovered quickly from soil water depletion, with the exception that sapwood area to stem area (As:Ast) was significantly lower in both species after the 2007 growing season compared to 2004. Results suggest that cottonwood has a greater sensitivity to interannual reductions in water availability, while willow is more sensitive to longer periods of soil water depletion. These data shed light on the linkage between soil water deficits and ecophysiological processes of threatened riparian forests given potential land-use and long-term drought impacts on freshwater resources

“Sometimes it’s more valuable than money:” using stories and local knowledge to document impacts of wild harvesting

Self-procurement strategies such as gardening, hunting, and wild harvesting are often overlooked in the development of local and regional food systems because the informal exchanges of these foods do not contribute to traditional financial impacts (McEntee 2011). Research conducted between 2017-2018 in the Missouri Ozarks partnered with wild harvesters and used narrative inquiry and critical reflection to explore the practice of wild harvesting, motivations for food access strategies, and the comprehensive wealth impacts of wild harvesting in the region. Comprehensive wealth, a USDA –Economic Research Service framework, provides a tool for economic development that considers multiple forms of capital and allows for evaluating a wider range of social, cultural, and other non-financial costs and benefits of local food systems investments within a local place. While the research was conducted in a rural area of Missouri, the results support a growing body of research that recognizes the need for strategies that strengthen both market and informal opportunities to participate in a local food system, whether urban or rural. This presentation will share results and comprehensive wealth indicators developed that could be used to evaluate impacts of wild harvesting activities in urban and rural communities. This project will also highlight the methodology of narrative inquiry to value local knowledge and participation in local food systems research

Comparison of methods to estimate Ephemeral Channel Recharge, Walnut Gulch, San Pedro River Basin, Arizona

Journal ArticleEphemeral channel transmission loss represents an important groundwater surface water exchange in arid and semiarid regions and is potentially a significant source of recharge at the basin scale. Copyright [year] American Geophysical Union. Reproduced by permission of American Geophysical Union. Further reproduction or electronic distribution is not permitted

Ecohydrological implications of woody plant encroachment

Journal ArticleIncreases in the abundance or density of woody plants in historically semiarid and arid grassland ecosystems have important ecological, hydrological, and socioeconomic implications. Using a simplified water-balance model, we propose a framework for conceptualizing how woody plant encroachment is likely to affect components of the water cycle within these ecosystems

Ecohydrologic significance of hydraulic redistribution in a semiarid savanna

Journal ArticleRecent studies have illuminated the process of hydraulic redistribution, defined as the translocation of soil moisture via plant root systems, but the long-term ecohydrologic significance of this process is poorly understood. Copyright [year] American Geophysical Union. Reproduced by permission of American Geophysical Union. Further reproduction or electronic distribution is not permitted

Introduction to local food systems

Original authors: Mary Hendrickson, Sarah Hultine Massengale and Crystal Weberstats092022upload"This guide explores the concept of local food systems and provides resources to help farmers, consumers and communities develop food systems that provide for profitable, thriving farms and businesses; steward our natural resources; and strengthen community relationships in rural and urban Missouri."--Page 1.Mary Hendrickson (Associate Professor, Rural Sociology), Sarah Hultine Massengale (Extension State Specialist in Community Development and Assistant Extension Professor, University of Missouri-St. Louis)Includes bibliographical reference

Ecohydrological consequences of non-native riparian vegetation in the southwestern United States: a review from an ecophysiological perspective

Protecting water resources for expanding human enterprise while conserving valued natural habitat is among the greatest challenges of the 21st century. Global change processes such as climate change and intensive land use pose significant threats to water resources, particularly in arid regions where potential evapotranspiration far exceeds annual rainfall. Potentially compounding these shortages is the progressive expansion of non-native plant species in riparian areas along streams, canals and rivers in geographically arid regions. This paper sets out to identify when and where non-native riparian plant species are likely to have the highest potential impact on hydrologic fluxes of arid and semiarid river systems. We develop an ecophysiological framework that focuses on two main criteria: (1) examination of the physiological traits that promote non-native species establishment and persistence across environmental gradients, and (2) assessment of where and to what extent hydrologic fluxes are potentially altered by the establishment of introduced species at varying scales from individual plants, to small river reaches, to entire river basins. We highlight three non-native plant species that currently dominate southwestern United States riparian forests. These include tamarisk (Tamarix spp.), Russian olive (Eleagnus angustifolia), and Russian knapweed (Acroptilon repens). As with other recent reviews, we suspect that in many cases the removal of these, and other non-native species will have little or no impact on either streamflow volume or groundwater levels. However, we identify potential exceptions where the expansion of non-native plant species could have significant impact on ecohydrologic processes associated with southwestern United States river systems. Future research needs are outlined that will ultimately assist land managers and policy makers with restoration and conservation priorities to preserve water resources and valued riparian habitat given limited economic resources