Islands are among the last regions on Earth settled and transformed by human activities, and they provide replicated model systems for analysis of how people affect ecological functions. By analyzing ...27 representative fossil pollen sequences encompassing the past 5000 years from islands globally, we quantified the rates of vegetation compositional change before and after human arrival. After human arrival, rates of turnover accelerate by a median factor of 11, with faster rates on islands colonized in the past 1500 years than for those colonized earlier. This global anthropogenic acceleration in turnover suggests that islands are on trajectories of continuing change. Strategies for biodiversity conservation and ecosystem restoration must acknowledge the long duration of human impacts and the degree to which ecological changes today differ from prehuman dynamics.
ABSTRACT
The general dynamic model of oceanic island biogeography (GDM) has added a new dimension to theoretical island biogeography in recognizing that geological processes are key drivers of the ...evolutionary processes of diversification and extinction within remote islands. It provides a dynamic and essentially non‐equilibrium framework generating novel predictions for emergent diversity properties of oceanic islands and archipelagos. Its publication in 2008 coincided with, and spurred on, renewed attention to the dynamics of remote islands. We review progress, both in testing the GDM's predictions and in developing and enhancing ecological–evolutionary understanding of oceanic island systems through the lens of the GDM. In particular, we focus on four main themes: (i) macroecological tests using a space‐for‐time rationale; (ii) extensions of theory to islands following different patterns of ontogeny; (iii) the implications of GDM dynamics for lineage diversification and trait evolution; and (iv) the potential for downscaling GDM dynamics to local‐scale ecological patterns and processes within islands. We also consider the implications of the GDM for understanding patterns of non‐native species diversity. We demonstrate the vitality of the field of island biogeography by identifying a range of potentially productive lines for future research.
Ecosystem services such as food provisioning, climate regulation, nutrient cycling, or recreation in open landscapes underpin human wellbeing. They are highly dependent on land use, land cover and ...utilization pattern as well as environmental factors like climate, topography and soil. In consequence, ecosystem services supply shows a high spatial variability. However, it is less clear if the perception of the importance of ecosystem services is similarly heterogeneous in space and amongst societal actors. The aim of this large-scale study was to explore whether land cover and climate gradients as well as socio-cultural factors influence the perceptions of ecosystem services of four groups of societal actors: citizens, farmers, foresters and nature managers. Spatially explicit survey data of 3018 respondents allowed to gain insight into the distribution of perceived importance of 21 ecosystem services in the federal state of Bavaria, Germany together with the respondents’ socio-cultural characterisation (e.g. gender, education and hobbies in nature). Responses were analysed through descriptive statistics, redundancy analysis, and Generalized Linear Models. Results reveal that the perceived importance of many ecosystem services was consistently high across groups, although perception differed for some ecosystem services (e.g. production of energy plants and timber as well as recreation in urban green space). Compared to other actor groups, farmers attributed slightly lower importance to all ES except provisioning services. Socio-cultural factors better explained variability in perceived importance of ecosystem services than land cover and climate gradients. This might be either explained by the fact that the environmental gradients vary not strong enough in our case study or that they do not shape the perceptions of respondents. A limitation of the study is that the sample of respondents obtained is not representative for the population, but biased towards persons interested in the topics of the survey. Still the consensus indicated by the overall positive perception of ecosystem services among respondents highlights the integrative potential of ecosystem services when included in decision-making.
The evolution of insular woodiness Zizka, Alexander; Onstein, Renske E; Rozzi, Roberto ...
Proceedings of the National Academy of Sciences - PNAS,
09/2022, Letnik:
119, Številka:
37
Journal Article
Recenzirano
Odprti dostop
Insular woodiness (IW)-the evolutionary transition from herbaceousness toward woodiness on islands-is one of the most iconic features of island floras. Since pioneering work by Darwin and Wallace, a ...number of drivers of IW have been proposed, such as 1) competition for sunlight requiring plants with taller and stronger woody stems and 2) drought favoring woodiness to safeguard root-to-shoot water transport. Alternatively, IW may be the indirect result of increased lifespan related to 3) a favorable aseasonal climate and/or 4) a lack of large native herbivores. However, information on the occurrence of IW is fragmented, hampering tests of these potential drivers. Here, we identify 1,097 insular woody species on 375 islands and infer at least 175 evolutionary transitions on 31 archipelagos, concentrated in six angiosperm families. Structural equation models reveal that the insular woody species richness on oceanic islands correlates with a favorable aseasonal climate, followed by increased drought and island isolation (approximating competition). When continental islands are also included, reduced herbivory pressure by large native mammals, increased drought, and island isolation are most relevant. Our results illustrate different trajectories leading to rampant convergent evolution toward IW and further emphasize archipelagos as natural laboratories of evolution, where similar abiotic or biotic conditions replicated evolution of similar traits.
The increasing popularity of digital media among protected area visitors poses challenges to protected area management. It alters the way visitors move and behave in the area, potentially increasing ...disturbance of nature, and it might also affect their expectation prior to the visit and their reflection on it. Simultaneously, digital media allow protected area managers to develop and implement new methods of digital visitor management (DVM). This may help to avoid conflicts and ensure compliance with rules and regulations and may have much further reaching positive consequences. Based on an online survey across 131 parks in 46 countries covering all continents, this study examined for the first time how protected areas view DVM. The results showed that the majority of park managers see digitalization as an opportunity, with 91% agreeing that it enables them to reach larger numbers of visitors and to provide real-time information. The advantage of integrating digital media into visitor monitoring was recognized. However, some park managers perceived digitalization as problematic, with 42% agreeing that it increases visitor load in sensitive areas and 40% agreeing that it leads to more off-trail activity. A clear majority of the respondents (61–91%) saw the proposed methods of DVM as effective or very effective. Accordingly, 70% of them envisioned using DVM in the future. Our findings suggest that the effects of digitalization in outdoor recreation are largely similar across the globe, with no significant influence of economic status or region. They offer insights into the potential of DVM for protected area management, but also its main obstacles. Adoption will be facilitated by increasing staff and funding for DVM. Additionally, knowledge exchange between protected areas can ease the successful implementation of new digital tools.
•Digitalization presents opportunities for protected area management worldwide.•Changes in visitation due to digital media may present challenges for protected area managers.•Most protected areas will use digital visitor management in the future.•Increasing funding and staff resources can help adopt digital visitor management.
Globally accelerating trends in societal development and human environmental impacts since the mid-twentieth century
are known as the Great Acceleration and have been discussed as a key indicator of ...the onset of the Anthropocene epoch
. While reports on ecological responses (for example, changes in species range or local extinctions) to the Great Acceleration are multiplying
, it is unknown whether such biotic responses are undergoing a similar acceleration over time. This knowledge gap stems from the limited availability of time series data on biodiversity changes across large temporal and geographical extents. Here we use a dataset of repeated plant surveys from 302 mountain summits across Europe, spanning 145 years of observation, to assess the temporal trajectory of mountain biodiversity changes as a globally coherent imprint of the Anthropocene. We find a continent-wide acceleration in the rate of increase in plant species richness, with five times as much species enrichment between 2007 and 2016 as fifty years ago, between 1957 and 1966. This acceleration is strikingly synchronized with accelerated global warming and is not linked to alternative global change drivers. The accelerating increases in species richness on mountain summits across this broad spatial extent demonstrate that acceleration in climate-induced biotic change is occurring even in remote places on Earth, with potentially far-ranging consequences not only for biodiversity, but also for ecosystem functioning and services.
Aim: Recent studies increasingly use statistical methods to infer biotic interactions from co-occurrence information at a large spatial scale. However, disentangling biotic interactions from other ...factors that can affect co-occurrence patterns at the macroscale is a major challenge. Approach: We present a set of questions that analysts and reviewers should ask to avoid erroneously attributing species association patterns to biotic interactions. Our questions relate to the appropriateness of data and models, the causality behind a correlative signal, and the problems associated with static data from dynamic systems. We summarize caveats reported by macroecological studies of biotic interactions and examine whether conclusions on the presence of biotic interactions are supported by the modelling approaches used. Findings: Irrespective of the method used, studies that set out to test for biotic interactions find statistical associations in species' co-occurrences. Yet, when compared with our list of questions, few purported interpretations of such associations as biotic interactions hold up to scrutiny. This does not dismiss the presence or importance of biotic interactions, but it highlights the risk of too lenient interpretation of the data. Combining model results with information from experiments and functional traits that are relevant for the biotic interaction of interest might strengthen conclusions. Main conclusions: Moving from species- to community-level models, including biotic interactions among species, is of great importance for process-based understanding and forecasting ecological responses. We hope that our questions will help to improve these models and facilitate the interpretation of their results. In essence, we conclude that ecologists have to recognize that a species association pattern in joint species distribution models will be driven not only by real biotic interactions, but also by shared habitat preferences, common migration history, phylogenetic history and shared response to missing environmental drivers, which specifically need to be discussed and, if possible, integrated into models.
Birds are among the best-studied animal groups, but their prehistoric diversity is poorly known due to low fossilization potential. Hence, while many human-driven bird extinctions (i.e., extinctions ...caused directly by human activities such as hunting, as well as indirectly through human-associated impacts such as land use change, fire, and the introduction of invasive species) have been recorded, the true number is likely much larger. Here, by combining recorded extinctions with model estimates based on the completeness of the fossil record, we suggest that at least ~1300-1500 bird species (~12% of the total) have gone extinct since the Late Pleistocene, with 55% of these extinctions undiscovered (not yet discovered or left no trace). We estimate that the Pacific accounts for 61% of total bird extinctions. Bird extinction rate varied through time with an intense episode ~1300 CE, which likely represents the largest human-driven vertebrate extinction wave ever, and a rate 80 (60-95) times the background extinction rate. Thus, humans have already driven more than one in nine bird species to extinction, with likely severe, and potentially irreversible, ecological and evolutionary consequences.
The prevention of biodiversity loss in agricultural landscapes to protect ecosystem stability and functions is of major importance to stabilize overall diversity. Intense agriculture leads to a loss ...in species richness and homogenization of species pools, but the processes behind are poorly understood due to a lack of systematic case studies: The specific impacts by agriculture in contrast to other land-use creating open habitat are not studied as such landscapes hardly exist in temperate regions.
Applying systematic grids, we compared the plant species distribution at the landscape scale between an active military training areas in Europe and an adjacent rather intensively used agricultural landscape. As the study areas differ mainly in the type of disturbance regime (agricultural vs. non-agricultural), differences in species pattern can be traced back more or less directly to the management. Species trait analyses and multiple measures of beta diversity were applied to differentiate between species similarities between plots, distance-decay, or nestedness.
Contrary to our expectation, overall beta diversity in the agricultural area was not reduced but increased under agricultural. This was probably the result of species nestedness due to fragmentation. The natural process of increasing dissimilarity with distance (distance-decay) was suppressed by intense agricultural land-use, generalist and long-distance dispersers gained importance, while rare species lost continuity.
There are two independent processes that need to be addressed separately to halt biodiversity loss in agricultural land. There is a need to conserve semi-natural open habitat patches of diverse size to favor poor dispersers and specialist species. At the same time, we stress the importance of mediating biotic homogenization caused by the decrease of distance-decay: The spread of long-distance dispersers in agricultural fields may be acceptable, however, optimized fertilizer input and erosion control are needed to stop the homogenization of environmental gradients due to nitrogen input into semi-natural habitat.
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•Processes responsible for species loss under intense agriculture are specified.•Plant species trait filtering lead to species nestedness and loss of distance decay.•Processes were induced by selection for generalist species and good dispersers.•N indicator values show eutrophication and homogenization under intense agriculture.•Action to combat phytodiversity loss must address both processes simultaneously.
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