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1.
Mol Hortic ; 4(1): 33, 2024 Sep 14.
Article in English | MEDLINE | ID: mdl-39272174

ABSTRACT

Fruit color substantially affects consumer preferences, with darker red strawberries being economically more valuable due to their higher anthocyanin content. However, the molecular basis for the dark red coloration remains unclear. Through screening of an ethyl methanesulfonate mutant library, we identified a rg418 mutant, that demonstrated anthocyanin accumulation during early fruit development stages. Furthermore, the ripening fruits of this mutant had higher anthocyanin content than wild-type (WT) fruits. An analysis of flavonoid content in WT and rg418 mutant fruits revealed substantial changes in metabolic fluxes, with the mutant exhibiting increased levels of anthocyanins and flavonols and decreased levels of proanthocyanidins. Bulked sergeant analysis sequencing indicated that the mutant gene was anthocyanidin reductase (ANR), a key gene in the proanthocyanidin synthesis pathway. Furthermore, transcriptome sequencing revealed the increased expression of MYB105 during the early development stage of mutant fruits, which promoted the expression of UFGT (UDP-glucose flavonoid 3-O-glucosyltransferase), a key gene involved in anthocyanin synthesis, thus substantially enhancing the anthocyanin content in the mutant fruits. Additionally, mutating ANR in a white-fruited strawberry variant (myb10 mutant) resulted in appealing pink-colored fruits, suggesting the diverse roles of ANR in fruit color regulation. Our study provides valuable theoretical insights for improving strawberry fruit color.

2.
Biol Lett ; 20(8): 20240033, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39140203

ABSTRACT

Characterizing the population density of species is a central interest in ecology. Eastern North America is the global hotspot for biodiversity of plethodontid salamanders, an inconspicuous component of terrestrial vertebrate communities, and among the most widespread is the eastern red-backed salamander, Plethodon cinereus. Previous work suggests population densities are high with significant geographic variation, but comparisons among locations are challenged by lack of standardization of methods and failure to accommodate imperfect detection. We present results from a large-scale research network that accounts for detection uncertainty using systematic survey protocols and robust statistical models. We analysed mark-recapture data from 18 study areas across much of the species range. Estimated salamander densities ranged from 1950 to 34 300 salamanders ha-1, with a median of 9965 salamanders ha-1. We compared these results to previous estimates for P. cinereus and other abundant terrestrial vertebrates. We demonstrate that overall the biomass of P. cinereus, a secondary consumer, is of similar or greater magnitude to widespread primary consumers such as white-tailed deer (Odocoileus virginianus) and Peromyscus mice, and two to three orders of magnitude greater than common secondary consumer species. Our results add empirical evidence that P. cinereus, and amphibians in general, are an outsized component of terrestrial vertebrate communities in temperate ecosystems.


Subject(s)
Biomass , Forests , Population Density , Urodela , Animals , Urodela/physiology , Biodiversity , North America
3.
J Exp Bot ; 75(18): 5857-5879, 2024 Sep 27.
Article in English | MEDLINE | ID: mdl-39023232

ABSTRACT

Domesticated strawberry is susceptible to sudden frost episodes, limiting the productivity of this cash crop in regions where they are grown during early spring. In contrast, the ancestral woodland strawberry (Fragaria vesca) has successfully colonized many habitats of the Northern Hemisphere. Thus, this species seems to harbour genetic factors promoting cold tolerance. Screening a germplasm established in the frame of the German Gene Bank for Crop Wild Relatives, we identified, among 70 wild accessions, a pair with contrasting cold tolerance. By following the physiological, biochemical, molecular, and metabolic responses of this contrasting pair, we identified the transcription factor Cold Box Factor 4 and the dehydrin Xero2 as molecular markers associated with superior tolerance to cold stress. Overexpression of green fluorescent protein fusions with Xero2 in tobacco BY-2 cells conferred cold tolerance to these recipient cells. A detailed analysis of the metabolome for the two contrasting genotypes allows the definition of metabolic signatures correlated with cold tolerance versus cold stress. This work provides a proof-of-concept for the value of crop wild relatives as genetic resources to identify genetic factors suitable to increase the stress resilience of crop plants.


Subject(s)
Cold Temperature , Fragaria , Plant Proteins , Fragaria/genetics , Fragaria/metabolism , Fragaria/physiology , Fragaria/growth & development , Plant Proteins/genetics , Plant Proteins/metabolism , Transcription Factors/metabolism , Transcription Factors/genetics , Gene Expression Regulation, Plant , Acclimatization , Nicotiana/genetics , Nicotiana/physiology , Nicotiana/metabolism
4.
Ecol Evol ; 14(7): e11542, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38979004

ABSTRACT

Strawberry or red leopards are a rare colour morph of leopard (Panthera pardus) characterised by spot markings that are red or brown instead of black, thought to be a result of a mutation in the tyrosinase-related protein (TYRP1) gene. We report the first record of this phenotype on the African continent outside of South Africa, from Selous Game Reserve in southern Tanzania. One female leopard with strawberry colouration was documented out of 373 individual leopards (0.3%) identified through camera trap surveys conducted from 2020 to 2022 over a combined area of more than 4600 km2 in the Nyerere-Selous landscape.

5.
J Environ Manage ; 364: 121498, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38897091

ABSTRACT

Livestock grazing occupies over a quarter of terrestrial land and is prevalent to agroforestry ecosystems, potentially affecting the survival, growth, and density of trees' early developmental stages, such as seeds, seedlings, and saplings. To address the effects of livestock on tree recruitment in the face of ongoing debates about their impacts, we conducted a 33-year meta-analysis in Quercus-dominated agroforestry systems. Our analysis revealed a consistently negative effect of livestock on oak acorns, seedlings, and saplings. Significantly, livestock body size influenced oak regeneration, with small-sized livestock, notably sheep and goats, having a more pronounced negative impact compared to mixed-size systems, mainly involving cattle and sheep. The effects of small-sized livestock were markedly detrimental on acorn survival and seedling/sapling density, although no studies eligible for meta-analysis examined large livestock impacts on acorns. Overall, mixed-size livestock systems, often involving cattle and sheep, lessen the negative effects. Our findings indicate that the body size and foraging behaviors of livestock should be considered for the ecological sustainability of the tree component in agroforestry systems. While protective measures have long been integral to well-managed agroforestry systems, our results underscore the importance of integrating diverse livestock sizes and applying specific protective strategies, particularly for acorns and saplings, to further refine these practices. Future research should expand to underrepresented regions and livestock types to refine global agroforestry management practices.


Subject(s)
Forestry , Livestock , Quercus , Trees , Quercus/growth & development , Animals , Ecosystem , Conservation of Natural Resources , Sheep , Cattle
6.
Am J Bot ; 111(7): e16362, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38943238

ABSTRACT

PREMISE: Theory predicts and empirical studies have shown that ecologically manipulated communities with high species diversity are resistant to invasion, but do these predictions and results hold true when applied to highly competitive invaders in natural communities? Few studies of diversity-mediated invasion resistance have measured both invasion resistance and invader impact in the same study. METHODS: We used a two-year field experiment to test: (1) diversity-mediated competitive resistance to patch expansion by the grass, Microstegium vimineum; and (2) the competitive effect of M. vimineum on resident plant diversity. We examined responses of M. vimineum to two native plant density-reduction treatments that had opposite effects on species diversity: (1) reducing species richness via the removal of rare species; and (2) reducing dominance by reducing the density of the dominant resident species. We examined the effects of M. vimineum reduction by pre-emergent herbicide on resident diversity in the second year of the study. RESULTS: Neither rare species removal nor dominant species reduction significantly increased M. vimineum density (relative growth rate). The pre-emergent herbicide dramatically reduced M. vimineum in year 2 of the study, but not most resident plants, which were perennials and indirectly benefited from the herbicide at a more productive site, presumably due to reduced competition from M. vimineum. CONCLUSIONS: Diversity-mediated resistance did not effectively deter invasion by a highly competitive invader. In the case of M. vimineum and at more productive sites, it would appear that nearly complete removal of this invader is necessary to preserve plant species diversity.


Subject(s)
Biodiversity , Herbicides , Introduced Species , Herbicides/pharmacology , Poaceae/physiology , Poaceae/growth & development
7.
Environ Manage ; 74(4): 636-647, 2024 Oct.
Article in English | MEDLINE | ID: mdl-38851641

ABSTRACT

In the Mediterranean, we find a mosaic of natural and cultural landscapes, where a variety of forest management practices created intermediate disturbance regimes that potentially increased biodiversity values. Nonetheless, it is essential to understand the species' long-term response to the dynamic management in agroecosystems, since the species tolerance to disturbance can change throughout the life cycle. Mammalian carnivores can be sensitive to human disturbance and are an essential part of ecosystems due to their regulatory and community structuring effects. We investigated the spatial response of five mesocarnivores species to spatially- and temporally- varying management practices in an agroforestry landscape. More specifically, we assessed the mesocarnivores' temporal changes in space use by implementing multi-season occupancy models in a Bayesian framework, using seasonal camera-trapping surveys for a 2-year period. All species had a weak response of local extinction to forestry management and livestock grazing pressure. For forest-dwelling species, occupancy was higher where productivity of perennial vegetation was high, while colonization between seasons was positively associated with vegetation cover. For habitat generalist species, we found that occupancy in the wet season increased with the distance to cattle exclusion plots. Most of these plots are pine stands which are subject to forestry interventions during winter. During the 2-year period we found seasonal fluctuations in occupancy for all species, with an overall slight decrease for three mesocarnivore species, while for the two forest-dwelling species there was an increase in occupancy between years. The weak species response to management practices supports the importance of traditional management for upholding a diverse mesocarnivore community in agroforestry systems but could also reflect these species' ecological plasticity and resilience to disturbance.


Subject(s)
Conservation of Natural Resources , Forestry , Seasons , Forestry/methods , Animals , Conservation of Natural Resources/methods , Forests , Biodiversity , Ecosystem , Agriculture/methods , Bayes Theorem
8.
New Phytol ; 243(1): 98-110, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38725410

ABSTRACT

Some plants exhibit dynamic hydraulic regulation, in which the strictness of hydraulic regulation (i.e. iso/anisohydry) changes in response to environmental conditions. However, the environmental controls over iso/anisohydry and the implications of flexible hydraulic regulation for plant productivity remain unknown. In Juniperus osteosperma, a drought-resistant dryland conifer, we collected a 5-month growing season time series of in situ, high temporal-resolution plant water potential ( Ψ ) and stand gross primary productivity (GPP). We quantified the stringency of hydraulic regulation associated with environmental covariates and evaluated how predawn water potential contributes to empirically predicting carbon uptake. Juniperus osteosperma showed less stringent hydraulic regulation (more anisohydric) after monsoon precipitation pulses, when soil moisture and atmospheric demand were high, and corresponded with GPP pulses. Predawn water potential matched the timing of GPP fluxes and improved estimates of GPP more strongly than soil and/or atmospheric moisture, notably resolving GPP underestimation before vegetation green-up. Flexible hydraulic regulation appears to allow J. osteosperma to prolong soil water extraction and, therefore, the period of high carbon uptake following monsoon precipitation pulses. Water potential and its dynamic regulation may account for why process-based and empirical models commonly underestimate the magnitude and temporal variability of dryland GPP.


Subject(s)
Carbon Cycle , Carbon , Ecosystem , Juniperus , Water , Juniperus/physiology , Water/metabolism , Carbon/metabolism , Soil/chemistry , Rain , Seasons , Droughts
9.
Ecol Evol ; 14(5): e11360, 2024 May.
Article in English | MEDLINE | ID: mdl-38706936

ABSTRACT

In degraded ecosystems, soil microbial communities (SMCs) may influence the outcomes of ecological restoration. Restoration practices can affect SMCs, though it is unclear how variation in the onset of restoration activities in woodlands affects SMCs, how those SMCs influence the performance of hard-to-establish woodland forbs, and how different woodland forbs shape SMCs. In this study, we quantified soil properties and species abundances in an oak woodland restoration chronosequence (young, intermediate, and old restorations). We measured the growth of three woodland forb species when inoculated with live whole-soil from young, intermediate, or old restorations. We used DNA metabarcoding to characterize SMCs of each inoculum treatment and the soil after conditioning by each plant species. Our goals were to (1) understand how time since the onset of restoration affected soil abiotic properties, plant communities, and SMCs in a restoration chronosequence, (2) test growth responses of three forb species to whole-soil inoculum from restoration sites, and (3) characterize changes in SMCs before and after conditioning by each forb species. Younger restored woodlands had greater fire-sensitive tree species and lower concentrations of soil phosphorous than intermediate or older restored woodlands. Bacterial and fungal soil communities varied significantly among sites. Forbs exhibited the greatest growth in soil from the young restoration. Each forb species developed a unique soil microbial community. Our results highlight how restoration practices affect SMCs, which can in turn affect the growth of hard-to-establish forb species. Our results also highlight that the choice of forb species can alter SMCs, which could have long-term potential consequences for restoration success.

10.
Plant Signal Behav ; 19(1): 2342744, 2024 Dec 31.
Article in English | MEDLINE | ID: mdl-38630633

ABSTRACT

Chloroplast photorelocation is a vital organellar response that optimizes photosynthesis in plants amid fluctuating environmental conditions. Chloroplasts exhibit an accumulation response, in which they move toward weak light to enhance photoreception, and an avoidance response, in which they move away from strong light to avoid photodamage. Although chloroplast photorelocation has been extensively studied in model plants such as Arabidopsis thaliana, little is known about this process in the economically important crop strawberry. Here, we investigated chloroplast photorelocation in leaf mesophyll cells of wild strawberry (Fragaria vesca), a diploid relative of commercially cultivated octoploid strawberry (F. × ananassa). Microscopy observation revealed that the periclinal area of leaf mesophyll cells in F. vesca is considerably smaller than that of A. thaliana. Given this small cell size, we investigated chloroplast photorelocation in F. vesca by measuring light transmittance in leaves. Weak blue light induced the accumulation response, whereas strong blue light induced the avoidance response. Unexpectedly, strong red light also induced the accumulation response in F. vesca. These findings shed light on chloroplast photorelocation as an intracellular response, laying the foundation for enhancing photosynthesis and productivity in Fragaria.


Subject(s)
Arabidopsis , Fragaria , Arabidopsis/physiology , Photosynthesis , Chloroplasts/metabolism , Plant Leaves
11.
Huan Jing Ke Xue ; 45(3): 1629-1643, 2024 Mar 08.
Article in Chinese | MEDLINE | ID: mdl-38471875

ABSTRACT

Coal mining is the world's primary means of coping with an increasing energy demand. However, with the mining of coal, the regional ecosystem has been damaged to varying degrees, resulting in a decrease in the "carbon sink" capacity. Vegetation restoration is the basis for the restoration of degraded ecosystems and carbon sequestration functions in mining areas. However, no systematic studies have been conducted on the effects of vegetation restoration on soil organic carbon in coal mining areas on a global scale. Therefore, it is not possible to accurately predict the response of the global SOC pool to vegetation restoration. In this study, soil physicochemical properties of vegetation restoration were collected from 112 peer-reviewed articles to assess the effects of vegetation restoration type, soil depth, restoration year, mean annual temperature, annual precipitation, and elevation on soil organic carbon in coal mining areas and to identify relevant key drivers. The results showed that the damaged coal mine area could significantly improve the physicochemical properties of the soil through vegetation restoration. The restored soils had 39.02% higher SOC reserves compared to that in unrestored or naturally restored soils. When environmental factors were not considered, the vegetation restoration types that were favorable for SOC stock accumulation were cropland > woodland > grassland > shrubland. All four types of vegetation restoration significantly increased the SOC storage in the surface layer (0-20 cm). Grassland and shrubs significantly increased SOC storage at depth (>40 cm), whereas SOC storage at depth under woodland and farmland types was not significantly different from SOC storage after unrestored or natural restoration. The increasing trend of SOC storage after vegetation restoration decreased with increasing soil depth. The specific vegetation restoration strategy should select the appropriate vegetation type according to the climatic conditions. The types of vegetation restoration with higher carbon sequestration effects in damaged coal mining areas with mean annual temperature <0℃ and mean annual precipitation <500 mm were grassland or shrubland. In contrast, woodland and cropland restoration types could better increase SOC storage in environments with mean annual temperature >15℃ and annual precipitation >800 mm. TN, BD, AN, and AK were the main factors influencing the ability to affect soil carbon sequestration. This study can provide a theoretical reference for quantifying the carbon sequestration effects of different vegetation restoration measures in damaged coal mining areas and the restoration and reconstruction of degraded ecosystems.

12.
Plant Soil ; 496(1-2): 71-82, 2024.
Article in English | MEDLINE | ID: mdl-38510945

ABSTRACT

Background and aims: Belowground interspecific plant facilitation is supposed to play a key role in enabling species co-existence in hyperdiverse ecosystems in extremely nutrient-poor, semi-arid habitats, such as Banksia woodlands in southwestern-Australia. Manganese (Mn) is readily mobilised by Banksia cluster root activity in most soils and accumulates in mature leaves of native Australian plant species without significant remobilisation during leaf senescence. We hypothesised that neighbouring shrubs are facilitated in terms of Mn uptake depending on distance to surrounding cluster root-forming Banksia trees. Methods: We mapped all Banksia trees and selected neighbouring shrubs within a study site in Western Australia. Soil samples were collected and analysed for physical properties and nutrient concentrations. To assesses the effect of Banksia tree proximity on leaf Mn concentrations [Mn] of non-cluster-rooted woody shrubs, samples of similarly aged leaves were taken. We used multiple linear models to test for factors affecting shrub leaf [Mn]. Results: None of the assessed soil parameters showed a significant correlation with shrub leaf Mn concentrations. However, we observed a significant positive effect of very close Banksia trees (2 m) on leaf [Mn] in one of the understorey shrubs. We found additional effects of elevation and shrub size. Conclusions: Leaf micronutrient concentrations of understorey shrubs were enhanced when growing within 2 m of tall Banksia trees. Our model predictions also indicate that belowground facilitation of Mn uptake was shrub size-dependent. We discuss this result in the light of plant water relations and shrub root system architecture. Supplementary Information: The online version contains supplementary material available at 10.1007/s11104-023-06092-6.

13.
Front Vet Sci ; 11: 1348736, 2024.
Article in English | MEDLINE | ID: mdl-38515533

ABSTRACT

Knowledge of how grazing cattle utilize heterogeneous landscapes in Mediterranean silvopastoral areas is scarce. Global positioning systems (GPS) to track animals, together with geographic information systems (GIS), can relate animal distribution to landscape features. With the aim to develop a general spatial model that provides accurate prediction of cattle resource selection patterns within a Mediterranean mountainous silvopastoral area, free-roaming Sarda cows were fitted with GPS collars to track their spatial behaviors. Resource selection function models (RSF) were developed to estimate the probability of resource use as a function of environmental variables. A set of over 500 candidate RSF models, composed of up to five environmental predictor variables, were fitted to data. To identify a final model providing a robust prediction of cattle resource selection pattern across the different seasons, the 10 best models (ranked on the basis of the AIC score) were fitted to seasonal data. Prediction performance of the models was evaluated with a Spearman correlation analysis using the GPS position data sets previously reserved for model validation. The final model emphasized that watering point, elevation, and distance to fences were important factors affecting cattle resource-selection patterns. The prediction performances (as Spearman rank correlation scores) of the final model, when fitted to each season, ranged between 0.7 and 0.94. The cows were more likely to select areas lower in elevation and farther from the watering point in winter than in summer (693 ± 1 m and 847 ± 13 m vs. 707 ± 1 m and 635 ± 21 m, respectively), and in spring opted for the areas furthest from the water (963 ± 12). Although caution should be exercised in generalizing to other silvopastoral areas, the satisfactory Spearman correlations scores from the final RSF model applied to different seasons indicate resource selection function is a powerful predictive model. The relative importance of the individual predictors within the model varied among the different seasons, demonstrating the RSF model's ability to interpret changes in animal behavior at different times of the year. The RSF model has proven to be a useful tool to interpret the spatial behaviors of cows grazing in Mediterranean silvopastoral areas and could therefore be helpful in managing and preserving ecosystem services of these areas.

14.
Ecol Appl ; 34(2): e2947, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38305124

ABSTRACT

Revegetation plantings are a key activity in farmland restoration and are commonly assumed to support biotic communities that, with time, replicate those of reference habitats. Restoration outcomes, however, can be highly variable and difficult to predict; hence there is value in quantifying restoration success to improve future efforts. We test the expectation that, over time, revegetation will restore bird communities to match those in reference habitats; and assess whether specific planting attributes enhance restoration success. We surveyed birds in 255 sites in south-east Australia, arranged along a restoration gradient encompassing three habitat types: unrestored farmland (paddocks), revegetation plantings (comprising a chronosequence up to 52 years old) and reference habitats (remnant native vegetation). Surveys were undertaken in 2006/2007 and again in 2019, with data used to compare bird assemblages between habitat types. We also determined whether, in the intervening 12 years, bird communities in revegetation had shifted toward reference habitats on the restoration gradient. Our results showed that each habitat contained a unique bird community and that, over time, assemblages in revegetation diverged away from those in unrestored farmland and converged toward those in reference habitats. Two planting attributes influenced this transition: the bird assemblages of revegetation were more likely to have diverged away from those of unrestored farmland (with scattered mature trees) 12 years later if they were located in areas with more surrounding tree cover, and were mostly ungrazed by livestock (compared with grazed plantings). Our results highlight three key ways in which revegetation contributes to farmland restoration: (1) by supporting richer and more diverse bird assemblages than unrestored farmland, (2) by enhancing beta diversity in rural landscapes through the addition of a unique bird community, and (3) by shifting bird assemblages toward those found in reference habitats over time. However, revegetation plantings did not replicate reference habitats by ~40-50 years in our region, and complete convergence may take centuries. These findings have implications for environmental offset programs and mean that effective conservation in farmland environments depends on the retention and protection of natural and seminatural habitats as a parallel management strategy to complement restoration.


Subject(s)
Biota , Birds , Animals , Farms , Livestock , Trees
15.
Environ Manage ; 73(4): 742-752, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38195904

ABSTRACT

Land use has a critical role to play in both climate change mitigation and biodiversity conservation, and increasingly there have been calls to integrate policies for concurrently meeting Paris Agreement commitments and the UN decade on ecosystem restoration 2021-2030. Currently however, investment activities have been dominated by climate change mitigation activities, including through the development of carbon markets (both voluntary and compliance markets). Whilst climate change mitigation is to be welcomed, the prioritization of carbon in avoided deforestation and reforestation can lead to suboptimal or negative outcomes for biodiversity. Restoration of degraded native vegetation may provide an opportunity for concurrent production of both carbon and biodiversity benefits, by harnessing existing carbon markets without the need to trade-off biodiversity outcomes. Here we demonstrate that carbon sequestered by restoring degraded temperate woodland can pay the price of the restored biodiversity. This is shown using conservative carbon prices in an established market (during both a voluntary and compliance market phase), and the restoration price revealed by a 10-year conservation incentive payment scheme. When recovery rates are high, market prices for carbon could pay the full price of restoration, with additional independent investment needed in cases where recovery trajectories are slower. Using carbon markets to fund restoration of degraded native vegetation thereby provides a solution for constrained resources and problematic trade-offs between carbon and biodiversity outcomes. Multi-attribute markets offer the potential to greatly increase the extent of restoration for biodiversity conservation, while providing an affordable source of carbon sequestration and enhancing economic benefits to landowners.


Subject(s)
Carbon , Ecosystem , Conservation of Natural Resources , Biodiversity , Forests , Carbon Sequestration
16.
J Environ Manage ; 351: 119950, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38150927

ABSTRACT

Amongst a spectrum of benefits, Nature-based Solutions (NBS) are increasingly being advocated as improving the quality of aquatic environments in urban areas. Of these, a widely adopted measure is tree planting. Yet, because of the local complexities and spatial variability of urban hydrological response, it is difficult to predict to what extent improvements in water quality will arise. To overcome this barrier, a standardised approach to process-based model simulation of urban river quality is described (QUESTOR-YARDSTICK (QUESTOR-YS)). The approach eliminates the influence of point sources of pollution and harmonises the way in which river hydrodynamics and contributory catchment size are represented. Thereby, it focuses on differences in water quality between cities due solely to climate, river discharge and urban diffuse nutrient pollution factors. The relative sensitivity to NBS establishment between urban water bodies in different cities anywhere across the world can also potentially be quantified. The method can be readily extended to include wastewater effluents. The validity of the approach is demonstrated for a small river in Birmingham, UK; and thence demonstrated for the case of 10 km of riparian tree planting in Birmingham, Oslo (Norway) and Aarhus (Denmark). Modelling suggests that riparian tree planting can substantially improve water quality in each example city for three key indicators of water quality in sensitive summer conditions (water temperature, chlorophyll-a and dissolved oxygen). Results show the level of benefit achievable in response to a fixed amount of planting will depend on the existing level of riparian tree occupancy.


Subject(s)
Trees , Water Quality , Cities , Wastewater , Temperature , Rivers , Environmental Monitoring
17.
Ecol Evol ; 13(11): e10658, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37915808

ABSTRACT

Investigating spatial patterns of animal occupancy and reproduction in peripheral populations can provide insight into factors that form species range boundaries. Following historical extirpation, American black bears (Ursus americanus) recolonized the western Great Basin in Nevada from the Sierra Nevada during the late 1900s. This range expansion, however, has not continued further into the Great Basin despite the presence of additional habitat. We aimed to quantify whether reduced reproduction toward the range edge contributes to this range boundary. We analyzed black bear detections from 100 camera traps deployed across black bear distribution in western Nevada using a multistate occupancy model that quantified the probability of occupancy and reproduction (i.e., female bears with cubs occupancy) in relation to changes in habitat type and habitat amount toward the range boundary. We detected a strong effect of habitat amount and habitat type on the probability of black bear occupancy and reproduction. At similar levels of landscape-scale habitat amount (e.g., 50%), estimated probability of occupancy for adult bears in piñon-juniper woodlands near the range boundary was 0.39, compared to ~1.0 in Sierra Nevada mixed-conifer forest (i.e., core habitat). Furthermore, estimated probability of cub occupancy, conditional on adult bear occupancy, in landscapes with 50% habitat was 0.32 in Great Basin piñon-juniper woodlands, compared to 0.92 in Sierra Nevada mixed-conifer forest. Black bear range in the western Great Basin conforms to the center-periphery hypothesis, with piñon-juniper woodland at the range edge supporting ecologically marginal habitat for the species compared to habitat in the Sierra Nevada. Further geographic expansion of black bears in the Great Basin may be limited by lower occupancy of reproducing females in piñon-juniper woodland. Center-periphery range dynamics may be common in large carnivore species, as their dispersal ability allows them to colonize low-quality habitat near range edges.

18.
J Environ Manage ; 348: 119036, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37857223

ABSTRACT

In western Canada, decades of oil-and-gas exploration have fragmented boreal landscapes with a dense network of linear forest disturbances (seismic lines). These seismic lines are implicated in the decline in wildlife populations that are adapted to function in unfragmented forest landscapes. In particular, anthropogenic disturbances have led to a decline of woodland caribou populations due to increasing predator access to core caribou habitat. Restoration of seismic lines aims to reduce the landscape fragmentation and stop the decline of caribou populations. However, planning restoration in complex landscapes can be challenging because it must account for a multitude of diverse aspects. To assist with restoration planning, we present a spatial network optimization approach that selects restoration locations in a fragmented landscape while addressing key environmental and logistical constraints. We applied the model to develop restoration scenarios in the Redrock-Prairie Creek caribou range in northwestern Alberta, Canada, which includes a combination of caribou habitat and active oil-and-gas and timber extraction areas. Our study applies network optimization at two distinct scales to address both the broad-scale restoration policy planning and project-level constraints at the level of individual forest sites. We first delineated a contiguous set of coarse-scale regions where restoration is most cost-effective and used this solution to solve a fine-scale network optimization model that addresses environmental and logistical planning constraints at the level of forest patches. Our two-tiered approach helps address the challenges of fine-scale spatial optimization of restoration activities. An additional coarse-scale optimization step finds a feasible starting solution for the fine-scale restoration problem, which serves to reduce the time to find an optimal solution. The added coarse-scale spatial constraints also make the fine-scale restoration solution align with the coarse-scale landscape features, which helps address the broad-scale restoration policies. The approach is generalizable and applicable to assist restoration planning in other regions fragmented by oil-and-gas activities.


Subject(s)
Reindeer , Animals , Conservation of Natural Resources , Ecosystem , Forests , Alberta
19.
PeerJ ; 11: e15951, 2023.
Article in English | MEDLINE | ID: mdl-37810793

ABSTRACT

Locating colonies of rare bats can be a time consuming process, as it is often difficult to know where to focus survey effort. However, identifying peaks of bat activity via acoustic monitoring may provide insights into whether a colony is locally present, and help screen out sites with low potential. Using a triage approach, we developed a survey methodology for locating colonies of the woodland-specialist barbastelle bat (Barbastella barbastellus). We investigated whether woodland occupancy by a colony could be predicted by acoustic data, and assessed the influence of survey effort (number of acoustic detectors deployed) on detectability. The methodology was then trialled in citizen science surveys of 77 woodlands, with follow-up radio-tracking surveys by specialists being used to confirm presence or absence. Using Receiver Operating Characteristic (ROC) curve analysis, we found that a threshold of four barbastelle passes recorded by at least one detector within one hour of sunset optimised the balance between the true- and false-positive rates. Subsequently, we found that a minimum survey effort of one detector per 6.25 hectares of woodland was needed to ensure a colony would be detected using this threshold, based on a survey sensitivity of 90%. Radio-tracking surveys in a subset of the woodlands, identified as having a high probability of being occupied by a colony based on acoustic monitoring, confirmed the presence of five previously unknown barbastelle maternity colonies. These results demonstrate that a triage system, in which high probability woodland sites are identified based on acoustic survey data, can be used to prioritise sites for future specialist surveys and conservation action.


Subject(s)
Chiroptera , Humans , Pregnancy , Animals , Female , Forests , Acoustics
20.
Plant Methods ; 19(1): 99, 2023 Sep 23.
Article in English | MEDLINE | ID: mdl-37742022

ABSTRACT

BACKGROUND: The diploid woodland strawberry (Fragaria vesca) is an excellent model plant for investigating economically significant traits and several genetic resources within the Rosaceae family. Agrobacterium rhizogenes-mediated hairy root transformation is an alternative for exploring gene functions, especially the genes specifically expressed in roots. However, the hairy root transformation has not been established in strawberry. RESULTS: Here, we described an efficient and rapid hairy root transgenic system for strawberry using A. rhizogenes. Strain of A. rhizogenes MSU440 or C58C1 was the most suitable for hairy root transformation. The transformation efficiency was highest when tissues contained hypocotyls as explants. The optimal procedure involves A. rhizogenes at an optical density (OD600) of 0.7 for 10 min and co-cultivation duration for four days, achieving a transgenic efficiency of up to 71.43%. An auxin responsive promoter DR5ver2 carrying an enhanced green fluorescent protein (eGFP) marker was transformed by A. rhizogenes MSU440, thereby generating transgenic hairy roots capable of high eGFP expression in root tip and meristem of strawberry where auxin accumulated. Finally, this system was applied for functional analysis using jGCaMP7c, which could sense calcium signals. A significant upsurge in eGFP expression in the transgenic hairy roots was displayed after adding calcium chloride. The results suggested that this approach was feasible for studying specific promoters and could be a tool to analyze gene functions in the roots of strawberries. CONCLUSION: We established a rapid and efficient hairy root transformation in strawberry by optimizing parameters, which was adequate for promoter analysis and functional characterization of candidate genes in strawberry and other rosaceous plants.

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