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Cnidarian-microalgae (Family: Symbiodiniaceae) endosymbiotic relationships are central to the success of reef building corals, particularly shaping stress tolerance and capacity to adapt to ever-changing environmental conditions. Studies have particularly examined Symbiodiniaceae susceptibility (and adaptation) to thermal stress to aid reef management as reef temperatures continue to rise. Thermal Performance Curves (TPCs) have previously been well studied to resolve how changing temperatures influence organism competitive fitness but have only recently been applied to corals and never before to Symbiodiniaceae. We therefore developed and applied rapid assay TPCs to 7 Symbiodiniaceae isolates (spanning 5 genera) from different reef origins. Isolates were exposed to temperature gradients, ramping up (26-35 °C) and down (26-17 °C) by 1 °C every 3 days. Photophysiological performance (maximum and effective photochemical efficiency, Fv/Fm and Fq´/Fm´) measured at each temperature was used to fit TPC algorithms describing temperature for optimal performance (Topt), critical thermal minimum or maximum (Ctmin or Ctmax), and thermal performance breadth (Tbr). TPC characteristics varied across the isolates revealing diverse performance ranges. Fv/Fm-derived Topt across all 7 isolates was 25.84 °C, with isolate WT3.2 (Symbiodinium spp.) returning the highest overall Topt (26.89 °C) and Ctmax (36.63 °C) values. In contrast, isolate RT141 (Breviolum psygmophilum) had the greatest Tbr (16.15 °C). As such, Fv/Fm-derived TPCs revealed thermal “generalism” of the temperate originating RT141 in comparison to more thermal “specialism” of WT3.2 originating from a hot tropical mangrove lagoon. Thermal characteristics were more varied across isolates when fitting TPCs to the effective photochemical efficiencies (Fq´/Fm´). We discuss how TPC-based characteristics are ultimately operationally defined in terms of thermal perturbation, choice of TPC algorithm and physiological descriptor, a

Coral propagation and out-planting are becoming commonly adopted as part of reef stewardship strategies aimed at improving reef resilience through enhanced natural recovery and rehabilitation. The coral microbiome has a crucial role in the success of the coral holobiont and can be impacted shortly after out-planting. However, long-term characterisation of the out-plant microbiome in relation to out-plant survival, and how these properties vary across reef sites, is unexplored. Therefore, at three reef sites on Opal Reef, Great Barrier Reef (Mojo, Sandbox and Rayban, 16°12′18″S 145°53′54″E), we examined bacterial communities associated with out-planted Acropora millepora coral and monitored coral survival over 12 months (February 2021–22). Bacterial communities of out-planted corals exhibited significant changes from donor colonies 7 days to 1.5 months after out-planting. Further, bacterial community composition differed for sites Sandbox and Rayban with low overall survival (0–43%) versus Mojo with higher overall survival (47–75%). After initial dissimilarity in bacterial communities of out-plants across sites at 1.5 months, and despite changes within sites over time, out-plants exhibited similar microbial communities across sites at 7 days and 6, 9 and 12 months. We hypothesise these trends reflect how bacterial communities are shaped by rapid changes in local environmental characteristics (e.g. from source to out-planting site), where out-plant bacterial communities ‘conform’ to out-planting site conditions. After initial changes, out-plant bacterial communities may then be under the influence of global environmental conditions—such as annual trends in temperature across seasons. Such outcomes indicate the importance of site selection in shaping initial coral bacterial communities and subsequent out-plant success. Importantly, continued differences in out-plant survival trajectory but similar bacterial communities across sites after 1.5 months indicate that other

Tourism-led stewardship of Great Barrier Reef (GBR) sites has implemented upscaling of coral propagation and out-planting practices. Incorporating ecological monitoring into restoration practices has long been acknowledged as a vital component of reef restoration projects – thereby demonstrating success in relation to improved ecosystem function within impacted reefs. As such, one goal for this tourism-led stewardship project was to identify whether and how activity increased coral cover and target species populations within high-value tourism sites. We therefore investigated coral cover and relative cover of commonly out-planted genera within seven tourism sites over six reefs on the northern GBR via benthic surveys, both prior to the commencement of out-planting activities in August 2019, and again in August 2021. Over this 24-month time frame, out-planting intensity varied between 3970 and 84 out-plants within marked areas (with no propagation activity conducted within corresponding control areas) across sites. Within all out-planting sites, > 65 % of out-plants were Acropora species. One reef showed a significant increase in hard coral cover – 10.3 % (p = 0.016) – at out-planting areas compared to control areas by August 2021. At this same reef, proportions of total coral cover attributed to Acropora species were higher within the out-planting site compared to the control site. Despite variability in coral community responses observed across reef site/operators, we have demonstrated how coral propagation via this tourism-led stewardship model has the potential to increase hard coral cover within some out-planting sites, particularly of commonly out-planted genera.

The prey naivety hypothesis posits that prey are vulnerable to introduced predators because many generations in slow gradual coevolution are needed for appropriate avoidance responses to develop. It predicts that prey will be more responsive to native than introduced predators and less responsive to introduced predators that differ substantially from native predators and from those newly established. To test these predictions, we conducted a global meta-analysis of studies that measured the wariness responses of small mammals to the scent of sympatric mammalian mesopredators. We identified 26 studies that met our selection criteria. These studies comprised 134 experiments reporting on the responses of 36 small mammal species to the scent of six introduced mesopredators and 12 native mesopredators. For each introduced mesopredator, we measured their phylogenetic and functional distance to local native mesopredators and the number of years sympatric with their prey. We used predator and prey body mass as a measure of predation risk. Globally, small mammals were similarly wary of the scent of native and introduced mesopredators; phylogenetic and functional distance between introduced mesopredators and closest native mesopredators had no effect on wariness; and wariness was unrelated to the number of prey generations, or years, since first contact with introduced mesopredators. Small mammal wariness was associated with predator-prey body mass ratio, regardless of the nativity. The one thing animals do not seem to recognize is whether their predators are native.

The diversity and distribution of marine species in eastern Australia is influenced by one of the world's strongest western boundary currents, the East Australia Current, which propels water and propagules poleward, a flow intensifying due to climate change. Population genetic structure of the asterinid sea star Meridiastra calcar was investigated across its range in eastern Australia (12° of latitude, 2,500 km) from northern New South Wales to its poleward-extending range in Tasmania at the southern edge influence of the East Australia Current. Population structure and connectivity of M. calcar were examined across six bioregions using six microsatellite loci (nuclear DNA) and the control region (mitochondrial DNA). The potential influence of the extent of M. calcar's intertidal rock platform habitat was also assessed. Genetic structure analysis indicated that the Hawkesbury Shelf contained distinct genetic clusters, whereas the two sites in the Batemans Shelf differed from each other, with Jervis Bay Marine Park having just one genetic cluster. The Manning Shelf, Twofold Shelf, and Bruny bioregions all had similar genetic composition. Strong self-seeding (68–98%) was indicated by microsatellite loci for all bioregions, with lower (0.3–6.5%) migration between bioregions. Poleward (New South Wales to Tasmania) migration was low except from the Manning Shelf (30%). Contemporary population connectivity and genetic structure of M. calcar appear to be influenced by ocean currents, habitat distribution, and its short planktonic larval duration, which was a minimum of 12–14 days, depending on availability of a settlement cue. The dominance of unique genetic groups in the Hawkesbury bioregion shows the importance of this region for M. calcar and possibly a diversity of co-distributed rock platform species. This highlights how important it is to have a large marine park in the Hawkesbury bioregion, which is presently lacking.

The ranges of many species globally have already shifted to maintain climatic equilibrium in the face of climate change. Biocrusts—soil surface dwelling communities of lichens, bryophytes and microbes—play important functional roles in many ecosystems, particularly in drylands. Compared to better studied animal and plant taxa, dryland biocrusts have different establishment requirements and have never been assessed for historical range shifts. Here, we revisited the sites (N = 204) of a 25-year-old biocrust survey across a large area (400,000 km2) of drylands in south-eastern Australia. We used quadratic models to quantify changes in the climate niches of 15 lichen, eight moss and five liverwort taxa, as well as biocrust cover and richness. Our models showed that the observed climatic niches of most taxa have become hotter and drier in the past quarter century, yet the responses of the vast majority of taxa are consistent with remaining in the same geographic space. A similar pattern was observed at the community level, where the peak of biocrust cover and richness now occurs in a hotter, drier environment. Notable exceptions were the liverwort Riccia lamellosa and lichens in the genera Cladonia and Xanthoparmelia, which showed signs of contraction at their arid range edges. Unlike more mobile taxa, most biocrust species have yet to shift geographically and may already be lagging behind the pace of climate change. One explanation for the mortality lag is that long-term climate variability in the system is extensive, which may have selected for the ability to withstand multi-year warm periods as long as there is an eventual return to milder conditions. However, no forecasts of future climate include a return to milder conditions, suggesting there will be an eventual loss of ecosystem multifunctionality at the contracting front. Expansion lags are most likely due to delays in the mortality of competing vascular plants. Synthesis: Our study provides a valuable contribut

Nutrient transported from soils to water bodies not only threatens agricultural productivity and food security but also causes the degradation of water quality and the environment in many parts of the world. However, nutrient transport through soil erosion is often ignored in nutrient cycle studies; there is little understanding of how much nutrient is lost through water and wind erosion. In this study, we attempted to assess soil nutrient transport due to both water and wind erosion and its spatial and temporal variability across New South Wales (NSW), Australia. We estimated the mass fraction (%) of total nitrogen (N), total phosphorus (P) and soil organic carbon (SOC) in the eroded soil, and the total nutrient stock of the soil layer down to 200 cm using water and wind erosion models and digital soil mapping. The estimated average N, P and SOC stocks in NSW topsoils (0–5 cm) are 160, 43, and 2970 kg ha−1 respectively. There are great variations in the transport of nutrients by erosion in space and time, ranging from near zero in the Western region to 395 kg ha−1 yr−1 in the North Coast region. The average total nutrient transport rate is about 2.4 % of the surface soil (0–5 cm) total stock in NSW due to both water and wind erosion. The total cost of nutrient transport is estimated at 4.2 billion Australian dollars for the entire state of NSW and 0.2 billion dollars from the cropping lands per year. The areas with the highest nutrient transport rates are the North Coast and Hunter regions due to the relatively high water erosion and nutrient content of the soils. On average, water erosion contributes up to 98 % of the total nutrient transport across the state as a whole, but wind erosion can contribute up to 12 % of the total transport in Spring (i.e., September). This study is the first attempt to investigate nutrient transport from both water and wind erosion in Australia. The methodology and findings contribute to the knowledge of nutrient transport due to eros

Monitoring trends in animal populations in arid regions is challenging due to remoteness and low population densities. However, detecting species' tracks or signs is an effective survey technique for monitoring population trends across large spatial and temporal scales. In this study, we developed a simulation framework to evaluate the performance of alternative track-based monitoring designs at detecting change in species distributions in arid Australia. We collated presence-absence records from 550 2-ha track-based plots for 11 vertebrates over 13 years and fitted ensemble species distribution models to predict occupancy in 2018. We simulated plausible changes in species' distributions over the next 15 years and, with estimates of detectability, simulated monitoring to evaluate the statistical power of three alternative monitoring scenarios: (1) where surveys were restricted to existing 2-ha plots, (2) where surveys were optimized to target all species equally, and (3) where surveys were optimized to target two species of conservation concern. Across all monitoring designs and scenarios, we found that power was higher when detecting increasing occupancy trends compared to decreasing trends owing to the relatively low levels of initial occupancy. Our results suggest that surveying 200 of the existing plots annually (with a small subset resurveyed twice within a year) will have at least an 80% chance of detecting 30% declines in occupancy for four of the five invasive species modeled and one of the six native species. This increased to 10 of the 11 species assuming larger (50%) declines. When plots were positioned to target all species equally, power improved slightly for most compared to the existing survey network. When plots were positioned to target two species of conservation concern (crest-tailed mulgara and dusky hopping mouse), power to detect 30% declines increased by 29% and 31% for these species, respectively, at the cost of reduced power for the remainin

Introduced large herbivores have partly filled ecological gaps formed in the late Pleistocene, when many of the Earth's megafauna were driven extinct. However, extant predators are generally considered incapable of exerting top-down influences on introduced megafauna, leading to unusually strong disturbance and herbivory relative to native herbivores. We report on the first documented predation of juvenile feral donkeys Equus africanus asinus by cougars Puma concolor in the Mojave and Sonoran Deserts of North America. We then investigated how cougar predation corresponds with differences in feral donkey behaviour and associated effects on desert wetlands. Focusing on a feral donkey population in the Death Valley National Park, we used camera traps and vegetation surveys to compare donkey activity patterns and impacts between wetlands with and without cougar predation. Donkeys were primarily diurnal at wetlands with cougar predation, thereby avoiding cougars. However, donkeys were active throughout the day and night at sites without predation. Donkeys were ~87% less active (measured as hours of activity a day) at wetlands with predation (p < 0.0001). Sites with predation had reduced donkey disturbance and herbivory, including ~46% fewer access trails, 43% less trampled bare ground and 192% more canopy cover (PERMANOVA, R2 = 0.22, p = 0.0003). Our study is the first to reveal a trophic cascade involving cougars, feral equids and vegetation. Cougar predation appears to rewire an ancient food web, with diverse implications for modern ecosystems. Our results suggest that protecting apex predators could have important implications for the ecological effects of introduced megafauna.

Surveys of larval fishes require accurate identifications of larvae which are essential to understand early life history of fish fish ecology and fisheries However the identification of larval fishes requires microscopic examination that is substantially more difficult than that of juvenile and adult fishes as many larval stages remain undescribed Furthermore the traditional formalin fixation of larval fishes were previously thought to prevent genetic sequencing compared to ethanol preserved larvae In this study we used an integrative taxonomic approach based on morphology imaging and DNA barcoding of the mitochondrial mtDNA cytochrome c oxidase subunit COI gene We used this approach in both cultured yellowtail kingfish Seriola lalandi and wild sourced fish larvae that had been fixed in 5 formalin Based on controlled and in field formalin treatments DNA barcoding and genetic species identification was 100 successful in cultured yellowtail kingfish fixed in formalin for up to 6 months while barcoding of wild caught fish larvae enabled species identification of 93 of up to 8 weeks formalin fixed specimens Furthermore we demonstrated the viability of using either whole larval individuals or a single eyeball removed

More than half of the fish biomass of coastal rocky reefs depends on zooplankton however the trophic basis of estuarine fish assemblages remains unknown We quantified the trophic basis i e basal energy sources of fish community biomass inhabiting three habitat types seagrass natural reef and artificial reef in two estuaries compared with two coastal rocky reef sites Fish assemblages were surveyed with Baited Remote Underwater Video BRUVs and the species abundance richness and biomass of fish were classified into nine functional feeding groups 6 teleost and 3 elasmobranch Comparable metrics for coastal fish assemblages were obtained from published surveys using BRUVs Using the functional feeding group biomass and the group specific diet composition the breakdown of energy sources was calculated using a food web analysis Estuarine reef habitats had different species and different functional feeding group composition than seagrass habitat The majority of fish biomass in the seagrass habitat was supported by detritus 51 in Botany Bay or macrophytes 58 in Lake Macquarie In contrast zooplankton supported most fish biomass 45 59 at the coastal reef locations and in reef habitat in one estuary 35 43 but not the other estuary 33 34 Trophic pathways which support fish assemblages are key in identifying mitigation measures which can help conserve these populations with growing urbanisation of estuaries and coasts 2022 The Author s under exclusive licence to Springer Verlag GmbH Germany part of Springer Nature

Analysis of environmental (e)DNA can facilitate an understanding of the presence and distribution of aquatic species. However, eDNA detection using quantitative PCR requires validated and standardized species-specific assay designs. This study presents two eDNA assays to detect Murray cod, Maccullochella peelii, and mulloway, Argyrosomus japonicus (two ecologically vulnerable Australian species), based on small fragments of the mitochondrial 12S ribosomal RNA gene. A comprehensive description of species-specific assay development, from assay design to testing in silico, in vitro and in situ, has been included to guide effective assay design and validation in future studies. The results indicate that the assay was species specific for M. peelii within its natural distribution. However, the assay also amplified genomic DNA from two allopatric and endangered congeners (Maccullochella ikei and Maccullochella mariensis), thus potentially facilitating their eDNA detection elsewhere. In contrast, the A. japonicus assay was highly species specific with no amplification among close relatives. Both target-species assays are highly sensitive to as few as four and 10 copies per PCR reaction, respectively. This study has demonstrated that the assays assessed are effective tools for detecting the targeted species in situ from environmental DNA samples, which will assist efforts to conserve and manage their stocks.

BackgroundMost terrestrial vascular plants can assimilate soil obtained NO3- in their root and shoot.ScopeData from the literature are collated and analysed with respect to genotype and environmental effects on the partitioning of NO3- assimilation between root and shoot of terrestrial vascular plants.ConclusionsTemperate evergreen woody species in the Ericaceae and Pinaceae carry out most of their NO3- assimilation in the root when growing in low (0.5 mM) up to at least 5 mM soil NO3-. The root is the main site of NO3- assimilation for temperate deciduous woody species and perennial and annual herbaceous legume species at 0.5–1 mM NO3- but for many, shoot assimilation increases in importance with increased NO3- supply. Temperate perennial grasses and annual non-legume species and tropical/ sub-tropical species regardless of life-form, carry out a substantial, usually major proportion of their NO3- assimilation in shoots at NO3- concentrations above 0.5 mM. Furthermore, high NH4+ supply, mycorrhizal infection and infection by parasitic plants can increase the proportion of total plant NO3- assimilation carried out in the shoot while abiotic stress and elevated atmospheric [CO2] can cause this to decrease. Shoot NO3- assimilation is an advantage under non-stress conditions due to its positive effect on leaf expansion but can be a disadvantage under freezing and chilling stress conditions. Increased reliance on root NO3- assimilation at elevated CO2 was associated with increased and conversely decreased plant growth and NO3- assimilation depending on study. Resolution of these different findings across studies is an important area for further research.

This paper focuses on the use of quantum dots in plant biology as indicators of organic N and inorganic P uptake by, and distribution within, plants, including those with mycorrhizal symbionts. Quantum dots used in this way are fluorescent 2-15 nm diameter CdSe/ZnS semiconductors coated with organic N compounds or with apatite (solid calcium phosphate). While control experiments showed no uptake of the uncoated but otherwise identical quantum dots, experiments by other investigators showed uptake and movement within the plant of some of the other engineered nanoparticles that have been tested. The most likely mechanism of entry of quantum dots is endocytosis, contrasting with the movement of free dissolved amino acids and inorganic phosphate through integral plasma membrane transporters. Further work is needed comparing the results from quantum dot experiments with otherwise identical experiments using 15N labelling of amino acids and 32P and/or 33P labelling of inorganic phosphate not associated with quantum dots to test the validity of this use of quantum dots. A comparison is also needed of the toxicity of CdSe-based quantum dots with that of radioactive P isotopes.

Efforts are accelerating to protect and restore ecosystems globally. With trillions of dollars in ecosystem services at stake, no clear framework exists for developing or prioritizing approaches to restore coral reefs even as efforts and investment opportunities to do so grow worldwide. Restoration may buy time for climate change mitigation, but it lacks rigorous guidance to meet objectives of scalability and effectiveness. Lessons from restoration of terrestrial ecosystems can and should be rapidly adopted for coral reef restoration. We propose how the 10 golden rules of effective forest restoration can be translated to accelerate efforts to restore coral reefs based on established principles of resilience, management, and local stewardship. We summarize steps to undertake reef restoration as a management strategy in the context of the diverse ecosystem service values that coral reefs provide. Outlining a clear blueprint is timely as more stakeholders seek to undertake restoration as the UN Decade on Ecosystem Restoration begins.

Soil microbes are crucial for improving soil quality and productivity. Plastic film mulch (FM), in conjunction with fertilization, has significantly improved crop yields over vast areas of dryland production. However, how these practices affect soil microbial communities, especially as regards co-occurrence patterns within microbial taxa, is unclear. The objective of this study was to determine the effects of 10 years of FM and four nitrogen (N) fertilization rates [0 (N0), 100 (N100), 250 (N250), and 400 (N400) kg N ha−1] on soil bacterial and fungal diversity, community structure, composition, and the co-occurrence network in a rainfed maize (Zea mays L.) field on the Loess Plateau of China. Results showed that N fertilization and FM did not affect soil microbial biomass carbon, but these practices changed the soil bacterial and fungal community structures. The bacterial community structure was dominantly affected by N fertilization, owing to the increased soil N content and decreased soil pH, which reduced bacterial community diversity and altered the relative abundance of some copiotrophic/oligotrophic taxa (e.g., Gemmatimonadetes, Acidobacteria, Rokubacteria, and Planctomycetes). Plastic mulch played a greater role in regulating the fungal community structure, primarily because FM increased soil moisture and promoted soil organic matter decomposition, thereby reducing fungal richness and altered the relative abundance of Chytridiomycota, Mortierellomycota, Glomeromycota, and Mucoromycota. Moreover, FM mediated the effects of N fertilization by reducing soil N content, and then increased the N threshold that caused changes in microbial structure. Network analysis indicated that FM caused an unstable co-occurrence network with fewer positive and negative links, while N fertilization increased both positive and negative (except N400) links, indicating enhanced cooperation and competition among microbes. These results indicate that long-term plastic mulch and high

Nonpoint source pollution entering rivers will pollute water quality, degrading the health of aquatic ecosystems. However, owing to the lack of quantitative research on the effects of nonpoint source pollution on the structure of aquatic food webs, there is a lack of quantitative basis for river management. Nonpoint source pollution is not only difficult to control effectively, but also the success rate of water ecological restoration projects is low. With the increasing proportion of nonpoint source pollution in water environmental problems, it is urgent to quantitatively assess and predict the impact of nonpoint source pollution on the structure of food webs. Therefore, this thesis presents a method for quantitatively assessing and predicting the impact of nonpoint source pollution on the structure of food webs through using fuzzy clustering to screen the typical points of the impact of nonpoint source pollution, then using canonical correspondence analysis (CCA) and partial least squares regression analysis to comprehensively filtrate the driving factors affect food web that results in nonpoint source pollution, and then determining the impact of each driving factor on the structure of food webs. Finally, the change trend of food web structure is predicted. The results show that (1) the driving factors that the nonpoint source pollution that affects the food web structure is NH3-N and chemical oxygen demand (COD). The increase in NH3-N and COD promotes the growth of phytoplankton, causing the change of the primary productivity of the ecosystem, and ultimately changes the entire food web structure; (2) NH3-N and COD affect the stability, maturity, connectivity and complexity of the aquatic food web structure. The increase of NH3-N increases the connectivity and maturity of the food web structure but reduces complexity and stability; the increase of COD increases the connection of the food web structure, while reducing the other three indicators; (3) in some areas

Calls for global action on environmental issues have been popular since the 1970s and public interest in them has been raised by rallying people to the notion that we all share one world. One need look no further than the COVID-19 pandemic to realize that sharing a world does not mean an equally felt impact or equally shared burden among all people when that world is threatened. Despite the initial good intentions of this ‘one world’ voice, when applied to the oceans the term ‘one’ risks reflecting only the more privileged sectors of society and their worldviews, rather than the diverse circumstances and values underpinning the complexity of human–ocean relationships. While we support the authors' sentiments of unity, their recognition of the oceans' roles in our interconnectedness, and the lack of a planet (or ocean) ‘B’, we also want to stress that humanity is not all in the same boat, people do not have the same destination in mind and we set out into the ocean future from very different home ports. Even within a region or nation, different people in society are poised to benefit differently from the future ocean economy and environment, depending on how ocean governance is developed, and on the conservation actions that support its sustainability. Thus, while the paper by Laffoley et al. makes the important point that the biophysical properties of the ocean play a significant role in every society and every Earth system, we must question ‘the first, simple step of dropping the “s”, recognizing the ocean as a single entity, and referring to the ocean in the singular’ (Laffoley et al., 2020, p. 13) with regard to three risks associated with that seemingly ‘modest proposal’. The first risk is that calls for ‘one ocean’ can undermine the notion of and action for ocean or blue justice. Although air, water, soil and oceans are all interconnected global biophysical systems, their degradation is often felt most acutely at local levels, and by poor and historically margi

Although coexistence permeates conservation policy and action, increased public awareness has not necessarily translated into action despite concerted conservation education effort. To galvanize and focus prosocial behavior, education that extends compassion to an expansive moral circle of living beings may encourage values of inclusion that are critical for actualizing coexistence. We used a pre-test post-test design to characterize the set of species that mattered to 52 Australian primary school students and to evaluate how a humane education intervention that encourages moral expansiveness and compassion can impact who matters and why. Following the program, the number of species that mattered to students increased and students expanded their moral circles of inclusion as represented by norms of intrinsic value. By successfully promoting greater compassion for non-human animals, interventions like coexistence education programs, and policies that replace negative norms with those that affirm the value of all living beings, the public may develop deeper connections with other living beings and ultimately feel inspired to coexist with and protect earth's biodiversity.

Artificial plantation, established on non-forest lands in recent decades in China's Loess Plateau, play an important role in enhancing ecological restoration. However, soil phosphorus (P) dynamics following artificial plantation still remain unclear, especially at the regional scale. We aim to determine how do soil total P (TP) and available P (AP) change and how do drivers affect the dynamics of soil P following artificial plantation. Here we examined the effects of climate (precipitation and temperature), prior land use cover (cropland and barren land), current land use cover (forest, grassland, and shrubland), soil properties (soil organic carbon, bulk density, and pH), tree species, and plantation age on changes in soil TP and AP in top 100 cm following artificial plantation. Our examination was conducted based on a meta-analysis of 740 independent observations from 67 articles. The results showed that, across all the variations, TP concentrations significantly decreased by 17.5% in the top 100 cm soil layer following artificial plantation, with no significant change in AP. Concentration of TP in the 100 cm soil depth had a similar spatial pattern, characterized by a higher depletion in northwest area but lower depletion in southeast area. Climate, prior land use, tree species, and soil properties all played an important role on TP, while only tree species influenced AP response to artificial plantation. Our findings suggest that artificial plantation did not appear to directly induce P limitation because of the nearly unaltered AP in the regional scale. However, compared with lower TP depletion in southeast area, substantial declines in TP in northwest area may drive such region toward greater P limitation with the decrease of AP replenishment capacity in the future.

Volatilomics, the examination of all biogenic volatile organic compounds (BVOCs) emitted by an organism or system, holds potential as a novel screening tool for taxonomy, fitness, and ecological functioning. Volatilomics has been largely applied to terrestrial environments, but highly productive coastal marine systems, which are major sources of specific BVOCs, such as dimethyl sulfide, have been largely neglected. Volatilomic measurements are highly method-dependent, with different instrumentation impacting the diversity of identified BVOCs—therefore, understanding these biases is critical to reconcile studies. Here, we investigated BVOCs emitted by two species of coral endosymbiotic microalgae (Symbiodinium tridacnidorum and Durusdinium trenchii) using gas chromatography–mass spectrometry (GC–MS) and comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC × GC–TOFMS). Seven chemical classes were detected by both instruments, the most common being aromatic hydrocarbons. However, GC × GC resolved seven times more BVOCs than GC–MS (290 vs. 40), with a higher proportion of compounds tentatively identified (173 vs. 14). Notably, nine chemical classes were exclusively identified by GC × GC, including alkane, alkene, aldehyde, ester, and nitrile BVOCs—each potentially fulfilling undescribed functions in marine organisms. The microalgal species investigated shared a large proportion of BVOCs, and this result was consistent across instruments (97 and 98% shared compounds via GC × GC and GC–MS, respectively), suggesting consistent retrieval of general patterns between instruments. This method comparison is the first of its kind in marine systems and confirms the greater analytical power of GC × GC, required to help resolve complex BVOC emissions and the identification of their roles in marine systems.

Coral-reef fishes are shifting their distributions poleward in response to human-mediated ocean warming, yet the consequences for recipient temperate fish communities remain poorly understood. Behavioural modification is often the first response of species to environmental change, but we know little about how this might shape the ongoing colonisation by tropical fishes of temperate-latitude ecosystems under climate change. In a global hotspot of ocean warming (southeast Australia), we quantified 14 behavioural traits of invading tropical and local co-occurring temperate fishes at 10 sites across a 730 km latitudinal gradient as a proxy of species behavioural niche space in different climate ranges (subtropical, warm-temperate, cold-temperate). We found that tropical fishes (4 species) modified their behavioural niches as well as increased their overall behavioural niche breadth in their novel temperate ranges where temperate species predominate, but maintained a moderate to high niche segregation with native temperate species across latitudinal range position. Temperate species (3 co-occurring species) also modified their niches, but in contrast to tropical species, experienced an increased niche breadth towards subtropical ranges. Alterations to feeding and shoaling behaviours contributed most to niche modifications in tropical and temperate species, while behaviours related to alertness and escape from potential threats contributed least. We here show that at warmer and colder range edges where community structures are being reshuffled due to climate change, behavioural generalism and niche modification are potential mechanisms adopted by tropical range extenders and native-temperate fishes to adjust to novel species interactions under climate change.

The loss of hollow-bearing trees is a key threat for many hollow-dependent taxa. Nesting boxes have been widely used to offset tree hollow loss, but they have high rates of attrition, and, often, low rates of usage by target species. To counter these problems, chainsaw carved hollows (artificial cavities cut into trees) have become a popular alternative, yet little research has been published on their effectiveness. We examined the usage of 150 chainsaw carved hollows by cavity-dependent fauna in the central west of New South Wales using observations from traditional inspection methods and remote cameras. Between October 2017 and April 2019, we detected 21 species of vertebrates (two reptile, one amphibian, 10 bird, and eight mammal species) inside chainsaw carved hollows, but the number of species detected was dependent on the chosen monitoring method. We detected six species inside hollows during physical inspections, whereas remote cameras detected 21 species entering hollows. Cameras detected eight species using hollows as breeding sites, whereas physical inspections detected just four species. Cameras detected two threatened mammals (squirrel glider (Petaurus norfolcensis) and greater glider (Petauroides volans)) raising young inside hollows, yet we failed to detect these species during physical inspections. For birds, the two methods yielded equivalent results for detection of breeding events. Overall, our study showed that few cavity-dependent species used chainsaw carved hollows as breeding sites. This highlights how artificial hollows are not a substitute for retaining naturally occurring hollows in large trees and revegetation programs.

Recent debates around the meaning and implications of compassionate conservation suggest that some conservationists consider emotion a false and misleading basis for moral judgment and decision making. We trace these beliefs to a long-standing, gendered sociocultural convention and argue that the disparagement of emotion as a source of moral understanding is both empirically and morally problematic. According to the current scientific and philosophical understanding, reason and emotion are better understood as partners, rather than opposites. Nonetheless, the two have historically been seen as separate, with reason elevated in association with masculinity and emotion (especially nurturing emotion) dismissed or delegitimated in association with femininity. These associations can be situated in a broader, dualistic, and hierarchical logic used to maintain power for a dominant male (White, able-bodied, upper class, heterosexual) human class. We argue that emotion should be affirmed by conservationists for the novel and essential insights it contributes to conservation ethics. We consider the specific example of compassion and characterize it as an emotional experience of interdependence and shared vulnerability. This experience highlights conservationists' responsibilities to individual beings, enhancing established and widely accepted beliefs that conservationists have a duty to protect populations, species, and ecosystems (or biodiversity). We argue compassion, thus understood, should be embraced as a core virtue of conservation.

Cultural adaptation is one means by which conservationists may help populations adapt to threats. A learned behavior may protect an individual from a threat, and the behavior can be transmitted horizontally (within generations) and vertically (between generations), rapidly conferring population-level protection. Although possible in theory, it remains unclear whether such manipulations work in a conservation setting; what conditions are required for them to work; and how they might affect the evolutionary process. We examined models in which a population can adapt through both genetic and cultural mechanisms. Our work was motivated by the invasion of highly toxic cane toads (Rhinella marina) across northern Australia and the resultant declines of endangered northern quolls (Dasyurus hallucatus), which attack and are fatally poisoned by the toxic toads. We examined whether a novel management strategy in which wild quolls are trained to avoid toads can reduce extinction probability. We used a simulation model tailored to quoll life history. Within simulations, individuals were trained and a continuous evolving trait determined innate tendency to attack toads. We applied this model in a population viability setting. The strategy reduced extinction probability only when heritability of innate aversion was low (<20%) and when trained mothers trained >70% of their young to avoid toads. When these conditions were met, genetic adaptation was slower, but rapid cultural adaptation kept the population extant while genetic adaptation was completed. To gain insight into the evolutionary dynamics (in which we saw a transitory peak in cultural adaptation over time), we also developed a simple analytical model of evolutionary dynamics. This model showed that the strength of natural selection declined as the cultural transmission rate increased and that adaptation proceeded only when the rate of cultural transmission was below a critical value determined by the relative levels of pr

A better understanding of species and population responses to thermal stress is critical to predict changes in their distribution under warming scenarios. Seagrasses are a unique group of marine plants that play fundamental roles in marine environments and provide vital ecosystem services. Nevertheless, previous studies on seagrass thermal tolerance have focused exclusively on a handful of species, with the majority of these remaining virtually unexplored. Moreover, to date, no study has compared the response to thermal stress between northern and southern hemisphere seagrasses. Here, we conducted comparative mesocosm experiments using four seagrass species from the northern (i.e. Mediterranean: Posidonia oceanica, Cymodocea nodosa) and southern (i.e. Australia: Posidonia australis and Zostera muelleri) hemisphere as representative of two different life strategies, i.e. climax (P. oceanica, P. australis) and pioneer (C. nodosa, Z. muelleri). Plants acclimatized to the mesocosm conditions at ambient temperature (i.e. 26 °C) during a 5-week period, were exposed to a simulated marine heatwave (i.e. 32 °C) for 2 weeks. Measurements of plant responses, including photo-physiology, morphology, and pigment content, were performed at the end of the warming exposure. Results showed that warming had no significant effects on photosynthetic performances of northern hemisphere seagrasses while negatively impacted their southern hemisphere counterparts. Similarly, warming favored the growth of northern hemisphere plants, but strongly inhibited the development of southern hemisphere species. Furthermore, photo-physiological and pigment content results suggested pioneer seagrasses better dealt with warming than climax species. Our study provides more insights into the field of seagrass ecology and yields potential implication for future seagrass conservation and restoration activities.

© 2020 John Wiley & Sons, Ltd. Healthy river ecosystems are conducive to the sustainable use of water resources. As the climate change and human activities become more intense, the integrity of such ecosystems is seriously threatened. The maintenance of enough environmental flow (e-flow) for river ecosystems is the most effective way of protecting river health. Accurately and reasonably estimating e-flow is essential for river health maintenance. So far, few methods can quantitatively verify the e-flow results calculated by various e-flow methods, which reduces the success rate of ecological restoration projects on a global scale. Therefore, the Tennant method, wetted perimeter (WP) method, and adapted ecological hydraulic radius (AEHRA) method have been recognized by many scholars. The article used the combination of these three methods to calculate the e-flow and its meeting rate (actual flow/e-flow) and formed a new framework to verify e-flow results. First, the Shannon diversity index, index of biological integrity (IBI), and river health index are used to evaluate river health status. Then, we studied the relationship between e-flow meeting rates and three indices using field monitoring data on hydrology, water quality, and biological communities. Finally, we investigated the effects of different e-flow calculation methods on river health. Results show that the e-flow in the centre of the study area calculated by the Tennant and WP methods are relatively high (48.33–317 m3/s), whereas lower e-flow (0.03–21 m3/s) are observed in its southern and northern parts. The e-flow in the southern mountain area calculated by the AEHRA method (1.42 m3/s) is higher than those in the other regions determined by the same method. Furthermore, the highest values of river health—the Shannon diversity index (3.19), IBI (67.47), and river health index (0.65)—appear in mountainous areas that are less affected by human activities. The lowest values appear in the urban areas with riv

Decades of research and policy interventions on biodiversity have insufficiently addressed the dual issues of biodiversity degradation and social justice. New approaches are therefore needed. We devised a research and action agenda that calls for a collective task of revisiting biodiversity toward the goal of sustaining diverse and just futures for life on Earth. Revisiting biodiversity involves critically reflecting on past and present research, policy, and practice concerning biodiversity to inspire creative thinking about the future. The agenda was developed through a 2-year dialogue process that involved close to 300 experts from diverse disciplines and locations. This process was informed by social science insights that show biodiversity research and action is underpinned by choices about how problems are conceptualized. Recognizing knowledge, action, and ethics as inseparable, we synthesized a set of principles that help navigate the task of revisiting biodiversity. The agenda articulates 4 thematic areas for future research. First, researchers need to revisit biodiversity narratives by challenging conceptualizations that exclude diversity and entrench the separation of humans, cultures, economies, and societies from nature. Second, researchers should focus on the relationships between the Anthropocene, biodiversity, and culture by considering humanity and biodiversity as tied together in specific contexts. Third, researchers should focus on nature and economies by better accounting for the interacting structures of economic and financial systems as core drivers of biodiversity loss. Finally, researchers should enable transformative biodiversity research and action by reconfiguring relationships between human and nonhuman communities in and through science, policy, and practice. Revisiting biodiversity necessitates a renewed focus on dialogue among biodiversity communities and beyond that critically reflects on the past to channel research and action toward fo

© 2020 Elsevier B.V. Afforestation of cropland is recommended as an effective approach to enhance soil organic carbon (SOC) sequestration and labile organic C fractions. However, the stabilization of SOC and its labile organic C fractions on the Loess Plateau is largely unknown. Our objective was to quantify total SOC concentration and labile organic C fractions in the 0–20 cm soil depth for four land use types on the Loess Plateau, including cropland and three afforested areas (composed of R. pseudoacacia forests, P. tabuliformis forests, and R. pseudoacacia + P. tabuliformis mixed forests). Total SOC concentration, particulate organic C (POC), dissolved organic C (DOC), microbial biomass C (MBC), and potassium permanganate-oxidizable C (KMnO4-C) were measured. Carbon management index (CMI) was also calculated. Afforestation showed a significant positive effect on total SOC and labile organic C fractions, compared with cropland. Afforestation with R. pseudoacacia, P. tabuliformis, and R. pseudoacacia + P. tabuliformis significantly increased POC by 57.4%, 22.2%, and 44.4% in the 0–5 cm soil layer; and similar increases were observed in the 5–10 cm and 10–20 cm layers. Similar trends to those observed for POC in response to afforestation were also seen for DOC, MBC, and KMnO4-C. Afforestation with R. pseudoacacia resulted in the highest total SOC concentrations and labile organic C fractions among the three afforestation treatments. These findings suggested that although afforestation can significantly promote total SOC accumulation, especially with R. pseudoacacia, SOC may become more labile following afforestation in the future.

Coral bleaching is the single largest global threat to coral reefs worldwide. Integrating the diverse body of work on coral bleaching is critical to understanding and combating this global problem. Yet investigating the drivers, patterns, and processes of coral bleaching poses a major challenge. A recent review of published experiments revealed a wide range of experimental variables used across studies. Such a wide range of approaches enhances discovery, but without full transparency in the experimental and analytical methods used, can also make comparisons among studies challenging. To increase comparability but not stifle innovation, we propose a common framework for coral bleaching experiments that includes consideration of coral provenance, experimental conditions, and husbandry. For example, reporting the number of genets used, collection site conditions, the experimental temperature offset(s) from the maximum monthly mean (MMM) of the collection site, experimental light conditions, flow, and the feeding regime will greatly facilitate comparability across studies. Similarly, quantifying common response variables of endosymbiont (Symbiodiniaceae) and holobiont phenotypes (i.e., color, chlorophyll, endosymbiont cell density, mortality, and skeletal growth) could further facilitate cross-study comparisons. While no single bleaching experiment can provide the data necessary to determine global coral responses of all corals to current and future ocean warming, linking studies through a common framework as outlined here, would help increase comparability among experiments, facilitate synthetic insights into the causes and underlying mechanisms of coral bleaching, and reveal unique bleaching responses among genets, species, and regions. Such a collaborative framework that fosters transparency in methods used would strengthen comparisons among studies that can help inform coral reef management and facilitate conservation strategies to mitigate coral bleaching worldwide

Compassionate conservation argues that actions taken to protect the Earth's diversity of life should be guided by compassion for all sentient beings. A set of essays published in Conservation Biology call to reject compassionate conservation. Critics argue that there are situations in which harming animals in conservation programs is appropriate. Three core reasons can be summarized: (1) conservation's raison d'être is biodiversity protection; (2) conservation is already compassionate to nonhumans; and (3) conservation should be compassionate to humans. We analysed these arguments, finding that objections to compassionate conservation are expressions of human exceptionalism, the view that humans are of categorically separate and higher moral status than all other species. In contrast, compassionate conservationists believe that conservation should expand its moral community by recognising all sentient beings as persons. Personhood, in an ethical sense, implies an entity is owed respect, and should never be treated merely as a means to other ends. On scientific and ethical grounds, there are good reasons to extend personhood to nonhuman animals, particularly in conservation. The moral exclusion or subordination of nonhuman beings has served to legitimate the ongoing manipulation and exploitation of the more-than-human world, the very reason conservation was needed in the first place. We embrace compassion for its ability to dismantle human exceptionalism, to recognise nonhuman personhood, and to navigate a more expansive moral space. Article impact statement: The debate about compassionate conservation is about whether to recognize nonhuman personhood. This article is protected by copyright. All rights reserved.

Should conservationists use lethal management to control introduced wildlife populations? Should they kill individual animals to protect endangered species? Are trade-offs that prioritize some values at the expense of others morally appropriate? These sorts of ethical questions are common in conservation. In debating such questions, conservationists often seem to presume 1 of 2 possible answers: the act in question is right or it is wrong. But morality in conservation is considerably more complex than this simple binary suggests. A robust conservation ethic requires a vocabulary that gives voice to the uncertainty and unease that arise when what seems to be the best available course of action also seems to involve a measure of wrongdoing. The philosophical literature on moral residue and moral dilemmas supplies this vocabulary. Moral dilemmas arise when one must neglect certain moral requirements to fulfill others. Under such circumstances, even the best possible decision leaves a moral residue, which is experienced emotionally as some form of grief. Examples of conservation scenarios that leave a moral residue include management of introduced rabbits in Australia, trophy hunting in Africa, and forest management trade-offs in the Pacific Northwest. Moral residue is integral to the moral experience of conservationists today, and grief is an appropriate response to many decisions conservationists must make. Article impact statement: Defensible conservation decisions may neglect moral requirements, leaving a moral residue; conservationists should respond with grief.

© 2020 Metabolites in soil play an important role in regulating plant-microbe interactions and, thereby, plant performance. Biotic factors such as root exudation and microbial activity or abiotic factors such as the concentration of atmospheric carbon dioxide (CO2) can drive both quantitative and qualitative changes in soil metabolite profiles. While the impact of these factors, either in isolation or in combination, are underexplored in soil systems due to technical challenges, recent technological advances have enabled these hurdles to be overcome. Given the key role that mutualistic ectomycorrhizal (ECM) fungi play in forest soils through their symbiotic interaction with trees, and the foreseen changes in forest dynamics with climate change, we investigated the effect of the Eucalyptus grandis-Pisolithus albus (plant host-fungus) association on soil metabolite profiles under ambient and elevated CO2 conditions (aCO2 and eCO2). We found that significant metabolite enrichment predominately occurred in the rhizosphere where a strong effect by ECM fungus was also observed. Specific ECM fungus-induced metabolites were enriched concurrently with an increased host plant root:shoot ratio, suggesting that the influence of ECM fungus on rhizosphere metabolite profiles may impact plant growth. Strikingly, however, we found no observable differences in soil metabolite profiles between the aCO2 and eCO2 conditions, which may be due to nutrient limitation given the low level of nutrients found in typical eucalyptus forest soils. Overall, our findings increase our understanding of soil metabolic processes at the symbiotic plant-microbe interface under current and future atmospheric CO2 scenarios.