A Theoretical Framework to Quantify Ecosystem Pressure-Volume Relationships.

'Water potential' is the biophysically relevant measure of water status in vegetation relating to stomatal, canopy and hydraulic conductance, as well as mortality thresholds; yet, this cannot be directly related to measured and modelled fluxes of water at plot- to landscape-scale without understanding its relationship with 'water content'. The capacity for detecting vegetation water content via microwave remote sensing further increases the need to understand the link between water content and ecosystem function. In this review, we explore how the fundamental measures of water status, water potential and water content are linked at ecosystem-scale drawing on the existing theory of pressure-volume (PV) relationships.

PSInet: a new global water potential network.

Given the pressing challenges posed by climate change, it is crucial to develop a deeper understanding of the impacts of escalating drought and heat stress on terrestrial ecosystems and the vital services they offer. Soil and plant water potential play a pivotal role in governing the dynamics of water within ecosystems and exert direct control over plant function and mortality risk during periods of ecological stress. However, existing observations of water potential suffer from significant limitations, including their sporadic and discontinuous nature, inconsistent representation of relevant spatio-temporal scales and numerous methodological challenges.

Tree species explain only half of explained spatial variability in plant water sensitivity.

Spatiotemporal patterns of plant water uptake, loss, and storage exert a first-order control on photosynthesis and evapotranspiration. Many studies of plant responses to water stress have focused on differences between species because of their different stomatal closure, xylem conductance, and root traits. However, several other ecohydrological factors are also relevant, including soil hydraulics, topographically driven redistribution of water, plant adaptation to local climatic variations, and changes in vegetation density.

Tracing the invisible mutant ADNP protein in Helsmoortel-Van der Aa syndrome patients.

Heterozygous de novo mutations in the Activity-Dependent Neuroprotective Homeobox (ADNP) gene underlie Helsmoortel-Van der Aa syndrome (HVDAS). Most of these mutations are situated in the last exon and we previously demonstrated escape from nonsense-mediated decay by detecting mutant ADNP mRNA in patient blood. In this study, wild-type and ADNP mutants are investigated at the protein level and therefore optimal detection of the protein is required.

The Ecosystem as Super-Organ/ism, Revisited: Scaling Hydraulics to Forests under Climate Change.

Classic debates in community ecology focused on the complexities of considering an ecosystem as a super-organ or organism. New consideration of such perspectives could clarify mechanisms underlying the dynamics of forest carbon dioxide (CO2) uptake and water vapor loss, important for predicting and managing the future of Earth's ecosystems and climate system. Here, we provide a rubric for considering ecosystem traits as aggregated, systemic, or emergent, i.

ADNP dysregulates methylation and mitochondrial gene expression in the cerebellum of a Helsmoortel-Van der Aa syndrome autopsy case.

Background: Helsmoortel-Van der Aa syndrome is a neurodevelopmental disorder in which patients present with autism, intellectual disability, and frequent extra-neurological features such as feeding and gastrointestinal problems, visual impairments, and cardiac abnormalities. All patients exhibit heterozygous de novo nonsense or frameshift stop mutations in the Activity-Dependent Neuroprotective Protein (ADNP) gene, accounting for a prevalence of 0.2% of all autism cases worldwide.

A new empirical framework to quantify the hydraulic effects of soil and atmospheric drivers on plant water status.

Metrics to quantify regulation of plant water status at the daily as opposed to the seasonal scale do not presently exist. This gap is significant since plants are hypothesised to regulate their water potential not only with respect to slowly changing soil drought but also with respect to faster changes in air vapour pressure deficit (VPD), a variable whose importance for plant physiology is expected to grow because of higher temperatures in the coming decades. We present a metric, the stringency of water potential regulation, that can be employed at the daily scale and quantifies the effects exerted on plants by the separate and combined effect of soil and atmospheric drought.

Description of a rock-dwelling cichlid that re-invaded the sand substrate in Lake Malai, Africa.

Pseudotropheus Regan had been a catch-all genus for many of the rock-dwelling cichlids of Lake Malai, known as mbuna, for over half a century. Although many of the species previously assigned to this genus have since been allocated to other genera there are still about a dozen species in the genus that do not appear to be closely related to its type species, P. williamsi, but for which no better placement could be found.

Impacts of climate timescale on the stability of trait-environment relationships.

Predictive relationships between plant traits and environmental factors can be derived at global and regional scales, informing efforts to reorient ecological models around functional traits. However, in a changing climate, the environmental variables used as predictors in such relationships are far from stationary. This could yield errors in trait-environment model predictions if timescale is not accounted for.

Description of a geographically variable elongate rock-dwelling cichlid (Cichliformes: Cichlidae) from Lake Malaŵi, Africa.

The rock-dwelling cichlids from Lake Malaŵi, known as mbuna, comprise a diverse group of haplochromine fishes that are placed among 14 genera. Within the mbuna, Pseudotropheus is a polyphyletic genus, which has served as a catch-all for many of these fishes. Recently, many of the species-groups within Pseudotropheus have been elevated to separate genera.

Global patterns of water storage in the rooting zones of vegetation.

The rooting-zone water-storage capacity-the amount of water accessible to plants-controls the sensitivity of land-atmosphere exchange of water and carbon during dry periods. How the rooting-zone water-storage capacity varies spatially is largely unknown and not directly observable. Here we estimate rooting-zone water-storage capacity globally from the relationship between remotely sensed vegetation activity, measured by combining evapotranspiration, sun-induced fluorescence and radiation estimates, and the cumulative water deficit calculated from daily time series of precipitation and evapotranspiration.

Global net biome CO exchange predicted comparably well using parameter-environment relationships and plant functional types.

Accurate estimation and forecasts of net biome CO exchange (NBE) are vital for understanding the role of terrestrial ecosystems in a changing climate. Prior efforts to improve NBE predictions have predominantly focused on increasing models' structural realism (and thus complexity), but parametric error and uncertainty are also key determinants of model skill. Here, we investigate how different parameterization assumptions propagate into NBE prediction errors across the globe, pitting the traditional plant functional type (PFT)-based approach against a novel top-down, machine learning-based "environmental filtering" (EF) approach.

Historically inconsistent productivity and respiration fluxes in the global terrestrial carbon cycle.

The terrestrial carbon cycle is a major source of uncertainty in climate projections. Its dominant fluxes, gross primary productivity (GPP), and respiration (in particular soil respiration, R), are typically estimated from independent satellite-driven models and upscaled in situ measurements, respectively. We combine carbon-cycle flux estimates and partitioning coefficients to show that historical estimates of global GPP and R are irreconcilable.

Plant-water sensitivity regulates wildfire vulnerability.

Extreme wildfires extensively impact human health and the environment. Increasing vapour pressure deficit (VPD) has led to a chronic increase in wildfire area in the western United States, yet some regions have been more affected than others. Here we show that for the same increase in VPD, burned area increases more in regions where vegetation moisture shows greater sensitivity to water limitation (plant-water sensitivity; R = 0.

Descriptions of two new shell-dwelling species of Metriaclima (Cichlidae) from Lake Malai, Africa.

Metriaclima is the most speciose genus of rock-dwelling fishes (mbuna) found in Lake Malai with 32 described species and with about 40 recognized forms that still await formal description. The genus is comprised of many geographically narrow populations restricted to specific habitat landmarks, such as reefs or islands. A few species have taken to the open sandy habitat where empty gastropod shells provide shelter.

Detecting forest response to droughts with global observations of vegetation water content.

Droughts in a warming climate have become more common and more extreme, making understanding forest responses to water stress increasingly pressing. Analysis of water stress in trees has long focused on water potential in xylem and leaves, which influences stomatal closure and water flow through the soil-plant-atmosphere continuum. At the same time, changes of vegetation water content (VWC) are linked to a range of tree responses, including fluxes of water and carbon, mortality, flammability, and more.

Microcomputed tomography used to link head morphology and observed feeding behavior in cichlids of Lake Malaŵi.

Cichlids inhabiting the Great Lakes of Africa have radiated extremely rapidly, with Lake Malaŵi harboring some 850 species. This rapid radiation may be linked to the diversity in behaviors, sexual selection, and phenotypic plasticity. To determine the relationships between morphology and behaviors, microcomputed tomography (microCT) was used to observe internal morphological structures.