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1.
Sci Rep ; 14(1): 11369, 2024 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762699

RESUMO

Demand for ecological restoration of Earth's degraded ecosystems has increased significantly since the adoption of The Kunming-Montreal Global Biodiversity Framework in December 2022, with target 2 aiming to ensure that at least 30% of degraded ecosystems are under effective restoration by 2030. More recently, in December 2023, the Australian Parliament introduced the Nature Repair Act, which establishes a framework for the world's first legislated, national, voluntary biodiversity market. How can the effectiveness of these ambitious targets be measured? Natural Capital Accounting (NCA) provides a framework to measure changes in ecosystem condition that is applicable across ecosystems and potentially catalogue effects of restoration interventions to drive investment, improvement to practice, and ultimately, to better protect the Earth's ecosystems. However, the framework has not been tested in this context. In this progressive approach, we populated the leading global NCA framework with ecological data to quantify changes in ecosystem condition after restoration. In principle, NCA is fit for purpose, however, methodological refinements and ecological expertise are needed to unlock its full potential. These tweaks will facilitate adoption and standardisation of reporting as efforts ramp up to meet ambitious global restoration targets.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos , Recuperação e Remediação Ambiental/métodos , Austrália , Ecologia
2.
Commun Biol ; 6(1): 1220, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38040868

RESUMO

Covering approximately 40% of land surfaces, grasslands provide critical ecosystem services that rely on soil organisms. However, the global determinants of soil biodiversity and functioning remain underexplored. In this study, we investigate the drivers of soil microbial and detritivore activity in grasslands across a wide range of climatic conditions on five continents. We apply standardized treatments of nutrient addition and herbivore reduction, allowing us to disentangle the regional and local drivers of soil organism activity. We use structural equation modeling to assess the direct and indirect effects of local and regional drivers on soil biological activities. Microbial and detritivore activities are positively correlated across global grasslands. These correlations are shaped more by global climatic factors than by local treatments, with annual precipitation and soil water content explaining the majority of the variation. Nutrient addition tends to reduce microbial activity by enhancing plant growth, while herbivore reduction typically increases microbial and detritivore activity through increased soil moisture. Our findings emphasize soil moisture as a key driver of soil biological activity, highlighting the potential impacts of climate change, altered grazing pressure, and eutrophication on nutrient cycling and decomposition within grassland ecosystems.


Assuntos
Ecossistema , Pradaria , Solo/química , Microbiologia do Solo , Biodiversidade
3.
Mycorrhiza ; 33(3): 139-152, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37165145

RESUMO

Current literature suggests ecological niche differentiation between co-occurring Mucoromycotinian arbuscular mycorrhizal fungi (M-AMF) and Glomeromycotinian AMF (G-AMF), but experimental evidence is limited. We investigated the influence of soil age, water availability (wet and dry), and plant species (native Microlaena stipoides and exotic Trifolium subterraneum) on anatomical root colonisation and DNA profiles of M-AMF and G-AMF under glasshouse conditions. We grew seedlings of each species in soils collected from the four stages of a soil chronosequence, where pH decreases from the youngest to oldest stages, and phosphorus (P) is low in the youngest and oldest, but high in the intermediate stages. We scored the percentage of root length colonised and used DNA metabarcoding to profile fungal richness and community composition associated with treatment combinations. Soil age, water availability, and plant species were important influencers of root colonisation, although no M-AMF were visible following staining of M. stipoides roots. Soil age and host plant influenced fungal richness and community composition. However, response to soil age, potential host species, and water availability differed between M-AMF and G-AMF. Root colonisation of T. subterraneum by M-AMF and G-AMF was inversely correlated with soil P level. Community composition of M-AMF and G-AMF was structured by soil age and, to a lesser extent, plant species. Richness of M-AMF and G-AMF was negatively, and positively, correlated with available P, respectively. These findings are experimental evidence of ecological niche differentiation of M-AMF and G-AMF and invite further exploration into interactive effects of abiotic and biotic factors on their communities along successional trajectories.


Assuntos
Micorrizas , Micorrizas/fisiologia , Solo/química , Raízes de Plantas/microbiologia , Ecossistema , Água , Microbiologia do Solo , Fungos/fisiologia
4.
Ecol Evol ; 12(7): e9058, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35813918

RESUMO

Ecological restoration of former agricultural land can improve soil conditions, recover native vegetation, and provide fauna habitat. However, restoration benefits are often associated with time lags, as many attributes, such as leaf litter and coarse woody debris, need time to accumulate. Here, we experimentally tested whether adding mulch and logs to restoration sites in semi-arid Western Australia can accelerate restoration benefits. All sites had been cropped and then planted with native trees and shrubs (i.e., Eucalyptus, Melaleuca, and Acacia spp.) 10 years prior to our experiment, to re-establish the original temperate eucalypt woodland vegetation community. We used a Multi-site Before-After-Control-Impact (MBACI) design to test the effects on 30 abiotic and biotic response variables over a period of 2 years. Of the 30 response variables, a significant effect was found for just four variables: volumetric water content, decomposition, native herbaceous species cover and species richness of disturbance specialist ants. Mulch addition had a positive effect on soil moisture when compared to controls but suppressed growth of native (but not exotic) herbaceous plants. On plots with log additions, decomposition rates decreased, and species richness of disturbance specialist ants increased. However, we found no effect on total species richness and abundance of other ant species groups. The benefit of mulch to soil moisture was offset by its disbenefit to native herbs in our study. Given time, logs may also provide habitat for ant species that prefer concealed habitats. Indeed, benefits to other soil biophysical properties, vegetation, and ant fauna may require longer time frames to be detected. Further research is needed to determine whether the type, quantity, and context of mulch and log additions may improve their utility for old field restoration and whether effects on native herbs are correlated with idiosyncratic climatic conditions.

5.
Nat Ecol Evol ; 6(9): 1290-1298, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35879541

RESUMO

Ecological models predict that the effects of mammalian herbivore exclusion on plant diversity depend on resource availability and plant exposure to ungulate grazing over evolutionary time. Using an experiment replicated in 57 grasslands on six continents, with contrasting evolutionary history of grazing, we tested how resources (mean annual precipitation and soil nutrients) determine herbivore exclusion effects on plant diversity, richness and evenness. Here we show that at sites with a long history of ungulate grazing, herbivore exclusion reduced plant diversity by reducing both richness and evenness and the responses of richness and diversity to herbivore exclusion decreased with mean annual precipitation. At sites with a short history of grazing, the effects of herbivore exclusion were not related to precipitation but differed for native and exotic plant richness. Thus, plant species' evolutionary history of grazing continues to shape the response of the world's grasslands to changing mammalian herbivory.


Assuntos
Biodiversidade , Herbivoria , Animais , Mamíferos , Plantas , Solo
6.
Ecol Appl ; 32(3): e2547, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35080806

RESUMO

Understanding constraints to ecological restoration on former agricultural land has become increasingly important due to agricultural land degradation in the developed world, and growing evidence for enduring agricultural legacies that limit native species recovery. In particular, the removal of native plant biomass and subsequent disturbance of soil properties through farming activities can alter soil ecosystem processes. Planting of native plant species is a common approach to restoring native vegetation on agricultural land and is assumed to benefit soil ecosystem processes, but the degree to which altered soil chemical processes recover is poorly documented. We investigated recovery of soil chemical properties after restoration in semiarid Western Australia, hypothesizing that elevated nutrient concentrations would gradually decline post planting, but available phosphorus (P) concentrations would remain higher than reference conditions. We used a space-for-time substitution approach, comparing 10 planted old field plots with matched fallow cropland and reference woodlands. Sampling on planted old fields and reference woodland plots was stratified into open patches and under tree canopy to account for consistent differences between these areas. The most prominent legacy of cropping was significantly and substantially higher concentrations of soil available P in fallow croplands and restored old fields compared with reference woodlands. Soil mineral nitrogen (N) concentrations were elevated in fallow croplands compared to open patches in reference woodlands (ammonium and nitrate) and under the tree canopy (ammonium). However, in restored old fields, mineral N concentrations were similar to woodland sites, providing evidence for amelioration over time. No significant differences in nutrient concentrations under tree canopies compared with open patches had developed in the planted old fields, despite a distinction between open patches and he under ttree canopy in reference woodlands for total N. We conclude that soil P legacies in old fields may inhibit the recolonization of native species that are sensitive to, or uncompetitive at, elevated P concentrations. To achieve full recovery, further research is required to test restoration practices aimed at reducing soil P concentrations to facilitate native plant establishment and persistence.


Assuntos
Fósforo , Solo , Ecossistema , Florestas , Solo/química , Árvores
7.
New Phytol ; 233(3): 1369-1382, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34618929

RESUMO

Globally, agricultural land-use negatively affects soil biota that contribute to ecosystem functions such as nutrient cycling, yet arbuscular mycorrhizal fungi (AMF) are promoted as essential components of agroecosystems. Arbuscular mycorrhizal fungi include Glomeromycotinian AMF (G-AMF) and the arbuscule-producing fine root endophytes, recently re-classified into the Endogonales order within Mucoromycotina. The correct classification of Mucoromycotinian AMF (M-AMF) and the availability of new molecular tools can guide research to better the understanding of their diversity and ecology. To investigate the impact on G-AMF and M-AMF of agricultural land-use at a continental scale, we sampled DNA from paired farm and native sites across 10 Australian biomes. Glomeromycotinian AMF were present in both native and farm sites in all biomes. Putative M-AMF were favoured by farm sites, rare or absent in native sites, and almost entirely absent in tropical biomes. Temperature, rainfall, and soil pH were strong drivers of richness and community composition of both groups, and plant richness was an important mediator. Both fungal groups occupy different, but overlapping, ecological niches, with M-AMF thriving in temperate agricultural landscapes. Our findings invite exploration of the origin and spread of M-AMF and continued efforts to resolve the phylogeny of this newly reclassified group of AMF.


Assuntos
Micorrizas , Agricultura , Austrália , Ecossistema , Fungos , Raízes de Plantas/microbiologia , Solo/química , Microbiologia do Solo
8.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34260386

RESUMO

Anthropogenic nutrient enrichment is driving global biodiversity decline and modifying ecosystem functions. Theory suggests that plant functional types that fix atmospheric nitrogen have a competitive advantage in nitrogen-poor soils, but lose this advantage with increasing nitrogen supply. By contrast, the addition of phosphorus, potassium, and other nutrients may benefit such species in low-nutrient environments by enhancing their nitrogen-fixing capacity. We present a global-scale experiment confirming these predictions for nitrogen-fixing legumes (Fabaceae) across 45 grasslands on six continents. Nitrogen addition reduced legume cover, richness, and biomass, particularly in nitrogen-poor soils, while cover of non-nitrogen-fixing plants increased. The addition of phosphorous, potassium, and other nutrients enhanced legume abundance, but did not mitigate the negative effects of nitrogen addition. Increasing nitrogen supply thus has the potential to decrease the diversity and abundance of grassland legumes worldwide regardless of the availability of other nutrients, with consequences for biodiversity, food webs, ecosystem resilience, and genetic improvement of protein-rich agricultural plant species.


Assuntos
Fabaceae/fisiologia , Pradaria , Internacionalidade , Nitrogênio/farmacologia , Fósforo/farmacologia , Biodiversidade , Biomassa , Fabaceae/efeitos dos fármacos , Probabilidade
9.
J Environ Manage ; 282: 111912, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33461087

RESUMO

In many mining-intensive areas around the world, knowledge-sharing among companies is critical to advance best-practices in mine rehabilitation and closure. The academic literature documents innovative, best-practices options, yet these are often not accessible to field practitioners. Published mine closure plans provide relevant examples of standards accepted by regulators, however, regulations vary with jurisdiction and can change over time, limiting the utility of these plans. There is, therefore, a need for greater transparency and accessibility of practical knowledge to inform the definition of achievable completion criteria. The purpose of this study is to provide an overview of best-practices for the purpose of defining mine completion criteria. The methods comprise: i) a qualitative meta-analysis of the global peer-reviewed literature; and ii) three in-depth case studies in Western Australia. The research identifies ten key best-practices that could be potentially applied by mining proponents to guide the definition of successful completion criteria. These include: multiple references, monitoring and corrective actions, science-informed completion criteria, holistic rehabilitation, dynamic targets, leading indicators, integration of rehabilitation with mine operations, innovation-guided completion criteria, specific objectives and indicators and risk-based completion criteria. These best-practices are further examined through recent mine rehabilitation and closure programs of mid-to-large mining operators in Western Australia. Our findings provide the first comprehensive review of best-practices towards the definition of mine completion criteria, which are relevant to industries requiring rehabilitation of disturbed lands across Australian and international jurisdictions.


Assuntos
Conhecimento , Mineração , Austrália , Austrália Ocidental
10.
Ecol Evol ; 11(24): 17744-17761, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35003636

RESUMO

Biotic and abiotic factors interact with dominant plants-the locally most frequent or with the largest coverage-and nondominant plants differently, partially because dominant plants modify the environment where nondominant plants grow. For instance, if dominant plants compete strongly, they will deplete most resources, forcing nondominant plants into a narrower niche space. Conversely, if dominant plants are constrained by the environment, they might not exhaust available resources but instead may ameliorate environmental stressors that usually limit nondominants. Hence, the nature of interactions among nondominant species could be modified by dominant species. Furthermore, these differences could translate into a disparity in the phylogenetic relatedness among dominants compared to the relatedness among nondominants. By estimating phylogenetic dispersion in 78 grasslands across five continents, we found that dominant species were clustered (e.g., co-dominant grasses), suggesting dominant species are likely organized by environmental filtering, and that nondominant species were either randomly assembled or overdispersed. Traits showed similar trends for those sites (<50%) with sufficient trait data. Furthermore, several lineages scattered in the phylogeny had more nondominant species than expected at random, suggesting that traits common in nondominants are phylogenetically conserved and have evolved multiple times. We also explored environmental drivers of the dominant/nondominant disparity. We found different assembly patterns for dominants and nondominants, consistent with asymmetries in assembly mechanisms. Among the different postulated mechanisms, our results suggest two complementary hypotheses seldom explored: (1) Nondominant species include lineages adapted to thrive in the environment generated by dominant species. (2) Even when dominant species reduce resources to nondominant ones, dominant species could have a stronger positive effect on some nondominants by ameliorating environmental stressors affecting them, than by depleting resources and increasing the environmental stress to those nondominants. These results show that the dominant/nondominant asymmetry has ecological and evolutionary consequences fundamental to understand plant communities.

11.
Microb Ecol ; 81(4): 864-873, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33145650

RESUMO

Fine root endophytes (FRE) were traditionally considered a morphotype of arbuscular mycorrhizal fungi (AMF), but recent genetic studies demonstrate that FRE belong within the subphylum Mucoromycotina, rather than in the subphylum Glomeromycotina with the AMF. These findings prompt enquiry into the fundamental ecology of FRE and AMF. We sampled FRE and AMF in roots of Trifolium subterraneum from 58 sites across temperate southern Australia. We investigated the environmental drivers of composition, richness, and root colonization of FRE and AMF by using structural equation modelling and canonical correspondence analyses. Root colonization by FRE increased with increasing temperature and rainfall but decreased with increasing phosphorus (P). Root colonization by AMF increased with increasing soil organic carbon but decreased with increasing P. Richness of FRE decreased with increasing temperature and soil pH. Richness of AMF increased with increasing temperature and rainfall but decreased with increasing soil aluminium (Al) and pH. Aluminium, soil pH, and rainfall were, in decreasing order, the strongest drivers of community composition of FRE; they were also important drivers of community composition of AMF, along with temperature, in decreasing order: rainfall, Al, temperature, and soil pH. Thus, FRE and AMF showed the same responses to some (e.g. soil P, soil pH) and different responses to other (e.g. temperature) key environmental factors. Overall, our data are evidence for niche differentiation among these co-occurring mycorrhizal associates.


Assuntos
Micorrizas , Carbono , Endófitos/genética , Fungos , Raízes de Plantas , Solo , Microbiologia do Solo
12.
Front Microbiol ; 11: 2018, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013744

RESUMO

AIMS: Arbuscule-producing fine root endophytes (FRE) (previously incorrectly Glomus tenue) were recently placed within subphylum Mucoromycotina; the first report of arbuscules outside subphylum Glomeromycotina. Here, we aimed to estimate nutrient concentrations in plant and fungal structures of FRE and to test the utility of cryo-scanning electron microscopy (cryoSEM) for studying these fungi. METHODS: We used replicated cryoSEM and X-ray microanalysis of heavily colonized roots of Trifolium subterraneum. RESULTS: Intercellular hyphae and hyphae in developed arbuscules were consistently very thin; 1.35 ± 0.03 µm and 0.99 ± 0.03 µm in diameter, respectively (mean ± SE). Several intercellular hyphae were often adjacent to each other forming "hyphal ropes." Developed arbuscules showed higher phosphorus concentrations than senesced arbuscules and non-colonized structures. Senesced arbuscules showed greatly elevated concentrations of calcium and magnesium. CONCLUSION: While uniformly thin hyphae and hyphal ropes are distinct features of FRE, the morphology of fully developed arbuscules, elevated phosphorus in fungal structures, and accumulation of calcium with loss of structural integrity in senesced arbuscules are similar to glomeromycotinian fungi. Thus, we provide evidence that FRE may respond to similar host-plant signals or that the host plant may employ a similar mechanism of association with FRE and AMF.

13.
J Environ Manage ; 273: 111078, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32738742

RESUMO

The mining industry is a major contributor to Australia's economy. However, such returns may come at high environmental and social costs, including loss of biodiversity or heritage values. Thus, companies worldwide are required to rehabilitate mine sites to a state that is safe, non-polluting and capable of supporting an agreed post-mining land use. While national and international guidelines on mine rehabilitation and closure exist, there is a lack of guidance on how to define achievable and measurable criteria that reflect rehabilitation success. This often leads to discrepancies between proponents and regulators, which hinder progression towards mine closure and relinquishment. The purpose of this study was to develop a systematic framework for the definition of completion criteria for mine closure and rehabilitation. The study was informed by a global review of the literature and collaborative research with mining stakeholders from Western Australia. The proposed framework consists of six fundamental steps: 1) selection of post mining land use; 2) definition of aspects and closure objectives; 3) selection of reference(s); 4) selection of attributes; 5) definition of completion criteria; and 6) evaluation of performance. This framework is the first to provide a step-by-step guide for defining site-specific completion criteria and applying a risk-based monitoring approach throughout the life of mine. The framework is applicable across jurisdictions and industries, in Australia and internationally, that require similar rehabilitation of disturbed lands.


Assuntos
Biodiversidade , Mineração , Austrália , Monitoramento Ambiental , Austrália Ocidental
14.
Glob Chang Biol ; 26(8): 4572-4582, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32520438

RESUMO

Microbial processing of aggregate-unprotected organic matter inputs is key for soil fertility, long-term ecosystem carbon and nutrient sequestration and sustainable agriculture. We investigated the effects of adding multiple nutrients (nitrogen, phosphorus and potassium plus nine essential macro- and micro-nutrients) on decomposition and biochemical transformation of standard plant materials buried in 21 grasslands from four continents. Addition of multiple nutrients weakly but consistently increased decomposition and biochemical transformation of plant remains during the peak-season, concurrent with changes in microbial exoenzymatic activity. Higher mean annual precipitation and lower mean annual temperature were the main climatic drivers of higher decomposition rates, while biochemical transformation of plant remains was negatively related to temperature of the wettest quarter. Nutrients enhanced decomposition most at cool, high rainfall sites, indicating that in a warmer and drier future fertilized grassland soils will have an even more limited potential for microbial processing of plant remains.


Assuntos
Ecossistema , Pradaria , Carbono , Nitrogênio/análise , Nutrientes , Solo
15.
Ecol Evol ; 8(17): 8652-8664, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30271534

RESUMO

The majority of terrestrial plants form mutualistic associations with arbuscular mycorrhizal fungi (AMF) and rhizobia (i.e., nitrogen-fixing bacteria). Understanding these associations has important implications for ecological theory and for restoration practice. Here, we tested whether the presence of AMF and rhizobia influences the performance of native woody plants invaded by a non-native grass in experimental microcosms. We planted eight plant species (i.e., Acacia acuminata, A. microbotrya, Eucalyptus loxophleba subsp. loxophleba, E. astringens, Calothamnus quadrifidus, Callistemon phoeniceus, Hakea lissocarpha and H. prostrata) in microcosms of field-conditioned soil with and without addition of AMF and rhizobia in a fully factorial experimental design. After seedling establishment, we seeded half the microcosms with an invasive grass Bromus diandrus. We measured shoot and root biomass of native plants and Bromus, and on roots, the percentage colonization by AMF, number of rhizobia-forming nodules and number of proteaceous root clusters. We found no effect of plant root symbionts or Bromus addition on performance of myrtaceous, and as predicted, proteaceous species as they rely little or not at all on AMF and rhizobia. Soil treatments with AMF and rhizobia had a strong positive effect (i.e., larger biomass) on native legumes (A. microbotrya and A. acuminata). However, the beneficial effect of root symbionts on legumes became negative (i.e., lower biomass and less nodules) if Bromus was present, especially for one legume, i.e., A. acuminata, suggesting a disruptive effect of the invader on the mutualism. We also found a stimulating effect of Bromus on root nodule production in A. microbotrya and AMF colonization in A. acuminata which could be indicative of legumes' increased resource acquisition requirement, i.e., for nitrogen and phosphorus, respectively, in response to the Bromus addition. We have demonstrated the importance of measuring belowground effects because the aboveground effects gave limited indication of the effects occurring belowground.

16.
Ecology ; 99(5): 1164-1172, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29603197

RESUMO

There is a need to find generalizable mechanisms supporting ecological resilience, resistance, and recovery. One hypothesized mechanism is landscape connectivity, a habitat configuration that allows movement of biotic and abiotic resources between local patches. Whether connectivity increases all or only one of resistance, resilience, and recovery has not been teased apart, however, and has been difficult to test at large scales and for complex trophic webs. Natural microcosms offer a complex system that can be manipulated to test questions at a landscape-scale relative to the community of study. Here, we test the role of connectivity in altering resistance, resilience, and recovery to a gradient of heating disturbance in moss microcosms. To test across trophic levels, we focused on community composition as our metric of response and applied three connectivity treatments - isolation, connected to an equally disturbed patch, and connected to an undisturbed patch. We found that connectivity between equally disturbed patches boosted resistance of communities to disturbance. Additionally, recovery was linear and rapid in communities connected to undisturbed landscapes, hump shaped when connected to equally disturbed landscapes, and linear but slow in isolated communities. We did not find thresholds on the disturbance gradient at which disturbed communities exhibited zero or increasing dissimilarity to controls through time, so were unable to draw conclusions on the role of connectivity in ecological resilience. Ultimately, isolated communities exhibited increasingly variable composition and slow recovery patterns even in control communities when compared with connected treatments.


Assuntos
Briófitas , Ecossistema
17.
Conserv Biol ; 32(3): 672-684, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29068083

RESUMO

Land-use change is the largest proximate threat to biodiversity yet remains one of the most complex to manage. In British Columbia (BC), where large mammals roam extensive tracts of intact habitat, continued land-use development is of global concern. Extant mammal diversity in BC is unrivalled in North America owing, in part, to its unique position at the intersection of alpine, boreal, and temperate biomes. Despite high conservation values, understanding of cumulative ecological impacts from human development is limited. Using cumulative-effects-assessment (CEA) methods, we assessed the current human footprint over 16 regional ecosystems and 7 large mammal species. Using historical and current range estimates of the mammals, we investigated impacts of human land use on species' persistence. For ecosystems, we found that bunchgrass, coastal Douglas fir, and ponderosa pine have been subjected to over 50% land-use conversion, and over 85% of their spatial extent has undergone either direct or estimated indirect impacts. Of the mammals we considered, wolves were the least affected by land conversion, yet all species had reduced ranges compared with historical estimates. We found evidence of a hard trade-off between development and conservation, most clearly for mammals with large distributions and ecosystems with high levels of conversion. Rather than serve as a platform to monitor species decline, we strongly advocate these data be used to inform land-use planning and to assess current conservation efforts. More generally, CEAs offer a robust tool to inform wildlife and habitat conservation at scale.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Biodiversidade , Colúmbia Britânica , Humanos , América do Norte
18.
Nat Ecol Evol ; 2(1): 50-56, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29203922

RESUMO

Biodiversity is declining in many local communities while also becoming increasingly homogenized across space. Experiments show that local plant species loss reduces ecosystem functioning and services, but the role of spatial homogenization of community composition and the potential interaction between diversity at different scales in maintaining ecosystem functioning remains unclear, especially when many functions are considered (ecosystem multifunctionality). We present an analysis of eight ecosystem functions measured in 65 grasslands worldwide. We find that more diverse grasslands-those with both species-rich local communities (α-diversity) and large compositional differences among localities (ß-diversity)-had higher levels of multifunctionality. Moreover, α- and ß-diversity synergistically affected multifunctionality, with higher levels of diversity at one scale amplifying the contribution to ecological functions at the other scale. The identity of species influencing ecosystem functioning differed among functions and across local communities, explaining why more diverse grasslands maintained greater functionality when more functions and localities were considered. These results were robust to variation in environmental drivers. Our findings reveal that plant diversity, at both local and landscape scales, contributes to the maintenance of multiple ecosystem services provided by grasslands. Preserving ecosystem functioning therefore requires conservation of biodiversity both within and among ecological communities.


Assuntos
Biodiversidade , Pradaria , Plantas , Modelos Biológicos , Análise Espacial
19.
J Environ Manage ; 208: 36-45, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29247883

RESUMO

Meeting conservation objectives in an era of global environmental change has precipitated debate about where and how to intervene. Ecological and social values of novel ecosystems are particularly contested. Governance has a role to play, but this role is underexplored. Here, we critically review the novel ecosystems literature to identify challenges that fall within the realm of governance. Using a conceptual framework for analysing adaptive governance, we consider how governance could help address five challenges. Specifically, we argue that reforming governance can support the re-framing of policy objectives for ecosystems where transformation is likely, and in doing so, it could highlight the tensions between the emergence of novel ecosystems on the one hand and cultural expectations about how ecosystems should look on the other. We discuss the influence of power, authority and administrative competence on conservation efforts in times of environmental change. We consider how buffering can address translational mismatch between conventional conservation policy and modern ecological reality. This review provides insights into how governance reform could enable more adaptive responses to transformative changes, such as novel ecosystems, while remaining committed to achieving conservation outcomes. Indeed, at their best, adaptive responses would encompass the reality of ecological transformation while being sympathetic to concerns about undesirable outcomes. Connections between researchers in the fields of governance, ecology and conservation could help to achieve these twin aims. We provide examples of governance and policy-making techniques that can support context-specific governance reform that supports more effective conservation in the Anthropocene.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Ecologia , Formulação de Políticas
20.
Trends Ecol Evol ; 33(2): 116-128, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29173900

RESUMO

Increased attention to species movement in response to environmental change highlights the need to consider changes in species distributions and altered biological assemblages. Such changes are well known from paleoecological studies, but have accelerated with ongoing pervasive human influence. In addition to species that move, some species will stay put, leading to an array of novel interactions. Species show a variety of responses that can allow movement or persistence. Conservation and restoration actions have traditionally focused on maintaining or returning species in particular places, but increasingly also include interventions that facilitate movement. Approaches are required that incorporate the fluidity of biotic assemblages into the goals set and interventions deployed.


Assuntos
Distribuição Animal , Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais/métodos , Dispersão Vegetal , Ecossistema
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