Reconsidering Resource Rights: The Case for a Basic Right to the Benefits of Life-Sustaining Ecosystem Services

In the presence of anthropogenic climate change, gross environmental degradation, and mass abject poverty, many political theorists currently debate issues such as people's right to water, the right to food, and the distribution of rights to natural resources more generally. However, thus far many theorists either focus (somewhat arbitrarily) only on one particular resource (e.g. water) or they treat all natural resources alike, meaning that many relevant distinctions within the group of natural resources are overlooked. Hence, the paper will start with an analysis of the various forms which natural resources can take and how this might influence one's conception of resource rights. In so doing, the paper argues that we have to carefully distinguish between the actual physical resources people might control and how we distribute these, and the life-sustaining benefits each and every person draws from sustainable and functioning ecosystems. Based on this distinction, the paper will argue for a right to the benefits of life-sustaining ecosystem services as a universal basic right every person has. Further distributive claims with respect to particular physical resources would thus be limited by the requirements of such a basic right.

Water-hydrophobic compound interactions with the microbial cell

The structural interactions of biological macromolecules, their biochemical activities and, ultimately, the metabolic function of cellular systems are dependent upon weak inter- and intra-molecular forces such as hydrogen bonds, Van der Waals forces, and the hydrophobic effect. Water molecules, and those of hydrophobic substances such as hydrocarbons, can take part in and/or modify these interactions and thereby determine the operational and structural stability of the microbial cell and its macromolecular systems. We explain how the cytosol, plasma membrane and the extracellular solution form a material and energetic continuum; and discuss the behavior of hydrophobic substances of extracellular origin as they migrate into the plasma membrane and into the cell's interior. The adverse effects of substances with a log P octanol-water =2, that partition into the hydrophobic domains of biological macromolecules, are discussed in relation to microbial cell function; and we speculate whether the cellular stress that they induce is symmetrical or asymmetrical in nature. In the context of the microbial environment, we take a situational-functional approach to consider how hydrophobic stressors interact with the microbial cell, and what types of evasion tactics microbes can employ to minimize their inhibitory activities. Finally, we discuss the ecological implications of hydrocarbon-induced cellular stress for microbial systems.

Influence of chloride, water, and organic solvents on the physical properties of ionic liquids

We report here the first systematic study of the effect of impurities and additives (e.g., water, chloride, and cosolvents) on the physical properties of room-temperature ionic liquids. Remarkably, it was discovered that the viscosity of mixtures was dependent mainly on the mole fraction of added molecular solvents and only to a lesser extent upon their identity, allowing viscosity changes during the course of a reaction to be entirely predictable. While the addition of such molecular solvents decreases the viscosity and density, chloride impurities, arising from the preparation of the ionic liquids, increase viscosity dramatically. The commonly used methods of preparation were validated with respect to chloride impurity.

Environmental Challenges and Physiological Solutions: Comparative Energetic Daily Rhythms of Field Mice Populations from Different Ecosystems

Daily and seasonal variations in physiological characteristics of mammals can be considered adaptations to temporal habitat variables. Across different ecosystems, physiological adjustments are expected to be sensitive to different environmental signals such as changes in photoperiod, temperature or water and food availability; the relative importance of a particular signal being dependent on the ecosystem in question. Energy intake, oxygen consumption (VO) and body temperature (T) daily rhythms were compared between two populations of the broad-toothed field mouse Apodemus mystacinus, one from a Mediterranean and another from a sub-Alpine ecosystem. Mice were acclimated to short-day (SD) 'winter' and long-day (LD) 'summer' photoperiods under different levels of salinity simulating osmotic challenges. Mediterranean mice had higher VO values than sub-Alpine mice. In addition, mice exposed to short days had higher VO values when given water with a high salinity compared with mice exposed to long days. By comparison, across both populations, increasing salinity resulted in a decreased T in SD- but not in LD-mice. Thus, SD-mice may conserve energy by decreasing T during ('winter') conditions which are expected to be cool, whereas LD-mice might do the opposite and maintain a higher T during ('summer') conditions which are expected to be warm. LD-mice behaved to reduce energy expenditure, which might be considered a useful trait during 'summer' conditions. Overall, increasing salinity was a clear signal for Mediterranean-mice with resultant effects on VO and T daily rhythms but had less of an effect on sub-Alpine mice, which were more responsive to changes in photoperiod. Results provide an insight into how different populations respond physiologically to various environmental challenges.

Water-mediated electrochemical nano-writing on thin ceria films

Bias dependent mechanisms of irreversible cathodic and anodic processes on a pure CeO2 film are studied using modified atomic force microscopy (AFM). For a moderate positive bias applied to the AFM tip an irreversible electrochemical reduction reaction is found, associated with significant local volume expansion. By changing the experimental conditions we are able to deduce the possible role of water in this process. Simultaneous detection of tip height and current allows the onset of conductivity and the electrochemical charge transfer process to be separated, further elucidating the reaction mechanism. The standard anodic/cathodic behavior is recovered in the high bias regime, where a sizable transport current flows between the tip and the film. These studies give insight into the mechanisms of the tip-induced electrochemical reactions as mediated by electronic currents, and into the role of water in these processes, as well as providing a different approach for electrochemical nano-writing.

Deep impact: in situ functional responses reveal context-dependent interactions between vertically migrating invasive and native mesopredators and shared prey

The ecological effects of invasive species depend on myriad environmental contexts, rendering understanding problematic. Functional responses provide a means to quantify resource use by consumers over short timescales and could therefore provide insight into how the effects of invasive species vary over space and time. Here, we use novel in situ microcosm experiments to track changes in the functional responses of two aquatic mesopredators, one native and the other an invader, as they undergo diel vertical migrations through a lake water column.
The Ponto–Caspian mysid, Hemimysis anomala, a known ecologically damaging invader, generally had higher a functional response towards cladoceran prey than did a native trophic analogue, Mysis salemaai. However, this differential was spatiotemporally dependent, being minimal during the day on the lake bottom, and increasing at night, particularly inshore.
Because the functional response of the native predator was spatiotemporally consistent, the above pattern was driven by changes in the invader functional response over the diel cycle. In particular, the functional response of H. anomala was significantly reduced on the lake bottom during the daytime relative to night, and predation was especially pronounced in shallow surface waters.
We demonstrate the context dependency of the effects of an invasive predator on prey populations and emphasise the utility of functional responses as tools to inform our understanding of predator–prey interactions. In situ manipulations integrate experimental rigour with field relevance and have the potential to reveal how impacts manifest over a range of spatiotemporal scales.

The influence of water motion on the growth rate of the kelp Laminaria hyperborea

The kelp Laminaria hyperborea is a dominant component of the subtidal nearshore ecosystem and is subjected to a heterogeneous wave and current climate. Water motion is known to influence physiological processes in macroalgae such as photosynthesis and nutrient uptake attributed to mass-transfer limitation. The study attempts to establish the effect of water motion on the growth rates of blades and elongation rates of the stipes of L. hyperborea at adjacent wave-exposed and wave-sheltered locations over a 12month period from field observations. The observations were supported by detailed physical and chemical measurements (light, temperature, seawater nutrient concentrations and hydrodynamics) and of tissue carbon and nitrogen concentrations together with δ¹³carbon. Despite a 30% difference in the root mean square of the velocity (Vel_rms) between the two survey locations, there was no evidence to suggest that water motion had any direct influence on the growth rates of either the blades or elongation of stipes of L. hyperborea. No significant differences were observed between either environmental or plant physiological variables between the sheltered and exposed locations. Using an integral velocity parameter (Vel_rms) the present study also highlighted the importance of the tidally induced current component of water flow in the subtidal zone. 

Water and temperature relations of soil Actinobacteria

Actinobacteria perform essential functions within soils, and are dependent on available water to do so. We determined the water-activity (a_w) limits for cell division of Streptomyces albidoflavus, Streptomyces rectiviolaceus, Micromonospora grisea and Micromonospora (JCM 3050) over a range of temperatures, using culture media supplemented with a biologically permissive solute (glycerol). Each species grew optimally at 0.998 a_w (control; no added glycerol) and growth rates were near-optimal in the range 0.971–0.974 (1 M glycerol) at permissive temperatures. Each was capable of cell division at 0.916–0.924 a_w (2 M glycerol), but only S. albidoflavus grew at 0.895 or 0.897 a_w (3 M glycerol, at 30 and 37°C respectively). For S. albidoflavus, however, no growth occurred on media at ≤ 0.870 (4 M glycerol) during the 40-day assessment period, regardless of temperature, and a theoretical limit of 0.877 a_w was derived by extrapolation of growth curves. This level of solute tolerance is high for non-halophilic bacteria, but is consistent with reported limits for the growth and metabolic activities of soil microbes. The limit, within the range 0.895–0.870 a_w, is very much inferior to those for obligately halophilic bacteria and extremely halophilic or xerophilic fungi, and is inconsistent with earlier reports of cell division at 0.500 a_w. These findings are discussed in relation to planetary protection policy for space exploration and the microbiology of arid soils.

Ethanol-induced water stress and fungal growth

Fungal growth inhibition by ethanol was compared with that caused by five other agents of water stress (at 25, 40 and 42.5°C), using Aspergillus oryzae. Ethanol, KCl, glycerol, glucose, sorbitol, and polyethylene glycol 400 were incorporated into media at concentrations corresponding to water activity (a(w)) values in the range 1 to 0.75. Generally, as temperature increased there was a decrease in the a(w) value at which optimum growth occurred. The a(w) limit for growth on KCl, glycerol, glucose, sorbitol, or polyethylene glycol 400 media was about 0.85, regardless of temperature. However, the a(w) limit for growth on ethanol media varied between 0.97 and 0.99 a(w) and was temperature-dependent. Water stress accounted for up to 31, 18 and 6% of growth inhibition by ethanol at 25, 40, and 42.5°C, respectively. For media containing ethanol, the decrease in growth rate per unit of a(w) reduction was greater as temperature increased. However, ethanol-induced water stress remained constant regardless of temperature, suggesting that other inhibitory effects of ethanol are closely temperature- dependent. Water stress may account for considerably more than 30% of growth inhibition by ethanol in cells that remain metabolically active at higher ethanol concentrations.

The use of water soluble mucoadhesive gels for the intravesical delivery of epirubicin to the bladder for the treatment of non-muscle invasive bladder cancer

Objectives: To develop an epirubicin-loaded, water-soluble mucoadhesive gels that have the correct rheological properties to facilitate their delivery into the bladder via a catheter, while allowing for their spread across the bladder wall with limited expansion of the bladder and increasing the retention of epirubicin in the bladder and flushing with urine.

Methods: Epirubicin-loaded hydroxyl ethyl cellulose (HEC) and hydroxy propyl methyl cellulose (HPMC) gels were manufactured and tested for their rheological properties. Their ability to be pushed through a catheter was also assessed as was their in-vitro drug release, spreading in a bladder and retention of epirubicin after flushing with simulated urine.

Key findings: Epirubicin drug release was viscosity-dependent. The 1 and 1.5% HEC gels and the 1, 1.5 and 2% HPMC gels had the correct viscosity to be administered through a model catheter and spread evenly across the bladder wall under the pressure of the detrusor muscle. The epirubicin-loaded gels had an increased retention time in the bladder when compared with a standard intravesical solution of epirubicin, even after successive flushes with simulated urine.

Conclusion: The increased retention of epirubicin in the bladder by the HEC and HPMC gels warrant further investigation, using an in-vivo model, to assess their potential for use as treatment for non-muscle-invasive bladder cancer.

Bioavailability of 2,4-dichlorophenol associated with soil water-soluble humic material

Interaction of organic xenobiotics with soil water-soluble humic material (WSHM) may influence their environmental fate and bioavailability. We utilized bacterial assays (lux-based toxicity and mineralization by Burkholderia sp. RASC) to assess temporal changes in the bioavailability of [¹⁴C]-2,4-dichlorophenol (2,4-DCP) in soil water extracts (29.5 μg mL^-1 2,4-DCP; 840.2 μg mL^-1 organic carbon). HPLC determined and bioavailable concentrations were compared. Gel permeation chromatography (GPC) was used to confirm the association of a fraction (>50%) of [¹⁴C]-2,4-DCP with WSHM. Subtle differences in parameters describing 2,4-DCP mineralization curves were recorded for different soil-2,4-DCP contact times. Problems regarding the interpretation of mineralization data when assessing the bioavailability of toxic compounds are discussed. The lux-bioassay revealed a time-dependent reduction in 2,4-DCP bioavailability: after 7 d, less than 20% was bioavailable. However, GPC showed no quantitative difference in the amount of WSHM-associated 2,4-DCP over this time. These data suggest qualitative changes in the nature of the 2,4-DCP-WSHM association and that associated 2,4-DCP may exert a toxic effect. Although GPC distinguished between free- and WSHM-associated 2,4-DCP, it did not resolve the temporal shift in bioavailability revealed by the lux biosensor. These results stress that assessment of risk posed by chemicals must be considered using appropriate biological assays.

Balancing the (carbon) budget: Using linear inverse models to estimate carbon flows and mass-balance 13C:15N labelling experiments in low oxygen sediments.

Over 1 million km² of seafloor experience permanent low-oxygen conditions within oxygen minimum zones (OMZs). OMZs are predicted to grow as a consequence of climate change, potentially affecting oceanic biogeochemical cycles. The Arabian Sea OMZ impinges upon the western Indian continental margin at bathyal depths (150 - 1500 m) producing a strong depth dependent oxygen gradient at the sea floor. The influence of the OMZ upon the short term processing of organic matter by sediment ecosystems was investigated using in situ stable isotope pulse chase experiments. These deployed doses of ¹³C:¹⁵N labeled organic matter onto the sediment surface at four stations from across the OMZ (water depth 540 - 1100 m; [O₂] = 0.35 - 15 μM). In order to prevent experimentally anoxia, the mesocosms were not sealed. ¹³C and ¹⁵N labels were traced into sediment, bacteria, fauna and ¹³C into sediment porewater DIC and DOC. However, the DIC and DOC flux to the water column could not be measured, limiting our capacity to obtain mass-balance for C in each experimental mesocosm. Linear Inverse Modeling (LIM) provides a method to obtain a mass-balanced model of carbon flow that integrates stable-isotope tracer data with community biomass and biogeochemical flux data from a range of sources. Here we present an adaptation of the LIM methodology used to investigate how ecosystem structure influenced carbon flow across the Indian margin OMZ. We demonstrate how oxygen conditions affect food-web complexity, affecting the linkages between the bacteria, foraminifera and metazoan fauna, and their contributions to benthic respiration. The food-web models demonstrate how changes in ecosystem complexity are associated with oxygen availability across the OMZ and allow us to obtain a complete carbon budget for the stationa where stable-isotope labelling experiments were conducted.