An experimental evaluation of cattail (Typha spp.) cutting depths on subsequent regrowth

Citation: Moorberg, C. & Ahlers, A. (2020). An experimental evaluation of cattail (Typha spp.) cutting depths on subsequent regrowth.Cattail (Typha spp.) expansions can negatively affect both native wetland flora and fauna diversity, and active management is often needed to maintain wetland habitat quality. Cattail removal is often non-permanent, requiring repeated treatments to retard reestablishment. Mechanically cutting cattails is a common management technique, but it is unclear what cutting depths are optimal. We conducted an experiment at Cheyenne Bottoms Wildlife Area (Kansas, USA) during 2017-2019 to address this question. We established a randomized complete block design experiment with four blocks and three cutting treatments in July 2017, including cattail cut above water, cut below water, and an uncut control. We hypothesized that cattails cut below water would have reduced gas-exchange capabilities due to flooded aerenchyma. We quantified emergent stem densities in each plot in September 2017 to assess the effectiveness of simulated management actions. The above water treatment had significantly fewer total stems than both the control (p = 0.0003) and the below water treatments (p = 0.0203). The above water treatment also had significantly fewer stems than the control treatment (p = 0.0032). Our results suggest that management efforts focused on cutting cattails below water slow cattail reestablishment

Mitigating Environmental Externalities through Voluntary and Involuntary Water Reallocation: Nevada's Truckee-Carson River Basin

A transition from the era of building water projects and developing new supplies to an era of water reallocation is well underway in most of the West. Two decades ago, experts were debating the ability of western water institutions, originally conceived to serve the earliest non-native water diverters-irrigators and mines -- to adapt to the growing demands of cities. By acquiring water formerly used to grow crops, through voluntary market transactions, western cities have demonstrated that water law and policy prove flexible when the economic and political stakes are high enough.Initially fueled by urban growth, water reallocation is now being stimulated by a new array of forces. Throughout the West, water reallocation is beginning to reflect environmental benefits alongside the traditional uses for water in irrigation, cities, and industry. Some reallocations have involved market transfers of water arranged through voluntary negotiations; others have involved involuntary reallocations prompted by court rulings. This article argues that both types of reallocation will continue to be important in managing western water resources, but that each has quite different implications for the distribution of benefits and costs from reallocation

Lessons Learned and Next Steps in Energy Efficiency Measurement and Attribution: Energy Savings, Net to Gross, Non-Energy Benefits, and Persistence of Energy Efficiency Behavior

This white paper examines four topics addressing evaluation, measurement, and attribution of direct and indirect effects to energy efficiency and behavioral programs: Estimates of program savings (gross); Net savings derivation through free ridership / net to gross analyses; Indirect non-energy benefits / impacts (e.g., comfort, convenience, emissions, jobs); and, Persistence of savings

Amorphous interface layer in thin graphite films grown on the carbon face of SiC

Cross-sectional transmission electron microscopy (TEM) is used to characterize an amorphous layer observed at the interface in graphite and graphene films grown via thermal decomposition of C-face 4H-SiC. The amorphous layer does not to cover the entire interface, but uniform contiguous regions span microns of cross-sectional interface. Annular dark field scanning transmission electron microscopy (ADF-STEM) images and electron energy loss spectroscopy (EELS) demonstrate that the amorphous layer is a carbon-rich composition of Si/C. The amorphous layer is clearly observed in samples grown at 1600{\deg}C for a range of growth pressures in argon, but not at 1500{\deg}C, suggesting a temperature-dependent formation mechanism

Hegel avec Kleist: On Marriage

This thesis investigates Hegel’s account of marriage in his Philosophy of Right as an ontological impasse which bears witness to a splitting and deadlock within his broader conception of ethical life (Sittlichkeit). As such, it is our aim to situate an opacity within the Hegelian self-conscious subject, as opposed to the subject attaining an inner self-awareness and transparently reflexive agency and, to this end, we put Hegel into conversation with his contemporary, Heinrich von Kleist. From this standpoint, we show in the first chapter how the thinker against whom Hegel formulates his account of marriage is Immanuel Kant who approached marriage as a contract. We map the rift between Kant and Hegel to the psychoanalytic concepts of desire and drive, in which Hegel takes desire to its breaking point, passing over to the problematic of sublimation (as distinct from the idealization we see in Kant’s account). In the second chapter, we investigate the performative role the wedding ceremony plays in Hegel’s account, in which the spoken vows, as the symbolic inscription and mediation of the marriage, show how symbolic repression through language does not take place without remainder. Finally, in the third chapter we interrogate the “Entschluss” at stake in marriage, a term that translates to decision and resolve, which we situate as an existential decision as opposed to an everyday choice; here we put Hegel into conversation with Schelling in order to see how German idealism situates the subject as ‘not-All,’ as opposed to an undivided identity