Helianthus maximiliani and species fine‐scale spatial pattern affect diversity interactions in reconstructed tallgrass prairies

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Line thinning enhances diversity of Coleoptera in overstocked Cryptomeria japonica plantations in central Japan

We evaluated the effectiveness of line thinning, a new silvicultural technique, toward restoring diversity of Coleoptera in overstocked Cryptomeria japonica D. Don plantations in central Japan. We compared the abundance of some common Coleoptera families between line-thinned stands and adjacent unthinned stands in two plantations: low-elevation Sugi site (4 years since thinning) and high-elevation Kuchiotani site (6 years since thinning). Many bettle families comprising various functional groups such as plant feeders, wood borers, rotten wood feeders, root feeders, fungus feeders, dung feeders, and scavengers were more abundant in the line-thinned stands than in the unthinned stands. Furthermore, some important families were missing from the unthinned stands. There were strong positive relationships between Coleopteran abundance and understory vegetation. Our results suggest that line thinning may potentially increase biodiversity in overstocked C. japonica plantations by restoring important ecological processes such as food-web interactions (pollination, predation, herbivory, decomposition, parasitism, etc.), and habitat conditions.     

From military training area to National Park over 20 years: Indicators for outcome evaluation in a large-scale restoration project in alpine Norway

There is a need for large-scale demonstrations to address the challenges and possibilities for upscaling of ecosystem restoration, and for learning and sharing knowledge across professions and habitats. Large-scale and complex restoration projects need new perspectives on goal formulation, indicators for success, and evaluation to encompass both scientific approaches and the tacit knowledge held by practitioners. The objective of this paper is to use the restoration of a 165 km² former military training area in alpine central Norway into National Park to demonstrate the challenges of upscaling and integration. Main tasks were to remove roads and technical infrastructure, prepare for natural recovery and remove undetonated ordnance. In total, 19 indicators were used to evaluate the restoration outcome, related to four overall restoration goals formulated by the Norwegian Parliament: nature protection, considerable nature benefit, safe civilian use, and restoration back to natural state. Despite an overall linear project cycle, a dynamic and adaptive process of planning, implementation and evaluation was performed at the individual site scale. A dynamic dialogue between all involved professions allowed for exchanging scientific and tacit knowledge, and continuous improvement of solutions. The study demonstrated the relevance of qualitative assessments combined with quantitative indicators – i.e., use of expert opinions and the continuous evaluation to feed back into planning and improving the implementation of restoration measures. A “Green training” procedure was developed, linking top-down formally defined settings of the project with bottom-up hand-on solutions. This procedure can be directly transferred to other large-scale mitigation and restoration projects. Demonstration sites like the one described here, are valuable to develop an expanded vision of restoration to meet the UN Sustainable Goals.     

The value of flagship and umbrella species for restoration and sustainable development: Bale monkeys and bamboo forest in Ethiopia

Forest loss and degradation are the most significant threats to terrestrial biodiversity in the tropics. Promoting flagship or umbrella species is a strategy that can be used to conserve intact forests and restore degraded ecosystems, conserve biodiversity, and achieve sustainable development goals. The Bale monkey (Chlorocebus djamdjamensis) is an arboreal, forest-dwelling, threatened primate restricted to a small range in the southern Ethiopian Highlands, which relies mostly on a single species of bamboo (Arundinaria alpina) and prefers bamboo forest habitat. Most of the Bale monkey’s range lies outside protected areas and most of its historical bamboo forest habitat is degraded or destroyed. The conservation of Bale monkeys and bamboo is highly inter-dependent; however, the value of using the Bale monkey as a flagship or umbrella species for forest restoration has not been evaluated. Here we use geographic range overlap and geospatial modeling to evaluate Bale monkeys as a flagship and/or umbrella species. We also assess if conservation intervention on behalf of Bale monkeys can help restore bamboo forest, while simultaneously providing a wide range of socioeconomic and environmental benefits. We found that Bale monkeys share their range with 52 endemic and/or threatened vertebrate species and at least 9 endemic and/or threatened plant species. Our results show that Bale monkeys meet both the flagship and umbrella species criteria to restore bamboo forest and conserve threatened co-occurring species. Since bamboo is fast-growing and can be harvested every year, we suggest that a science-based sustainable harvest and management regime for bamboo would help to improve the livelihood of both the local community and Ethiopians in general without significantly affecting the long-term survival of Bale monkeys and regional biodiversity. Further, a conservation management strategy protecting and restoring bamboo forest has the potential to achieve at least six of the 17 United Nations Sustainable Development Goals.     

The effects of two abundant ant species on soil nutrients and seedling recruitment in Brazilian Atlantic Forest

Ants can influence soil fertility and the spatial distribution of seeds, with possible effects on seedling recruitment. The ant species Pachycondyla striata Fr. Smith, 1858 and Odontomachus chelifer (Latreille, 1802) co-occur in many forest areas in the Neotropics. We assessed soil fertility and seed bank structure in soil samples close and distant (control) from ant nests in forest fragments. We also assessed the richness and abundance of seedlings on nests and control sites. In soil samples from ant nests, the concentration of phosphorus and potassium were respectively 55.6% and 36% higher than in control sites. Aluminium was 11–15% lower in soil samples from ant nests. In the greenhouse, soils from ant nests had higher plant abundance and species richness, but the same species composition in comparison with control sites. Although more plants emerged from soil samples of O. chelifer nests, in the field, the density and richness of seedlings were similar for the two ant species studied. Seedlings in the nest sites were, on average, 1.8 times more abundant and 1.6 times richer in species than in control sites. Our results showed that ant species can play a key role in seedling recruitment in forest fragments, where other animals with equivalent and positive effects, such as mammals, are missing.     

The value of biodiversity experiments

Recent biodiversity experiments have investigated the relationship between diversity and ecosystem functioning by synthesizing plant communities from pools of species that have been experimentally manipulated to vary numbers and types of species present while holding abiotic factors constant. Biodiversity experiments therefore focus on a previously under-explored aspect of global change: the feedback from diversity to environment. Consequences of random manipulation of species communities may not correspond well to those of specific extinction sequences observed in the past in response to extinction drivers that cause highly non-random loss. However, random manipulation provides a good starting point given that existing communities could undergo many alternative orders of species loss in the future in response to a variety of different potential extinction drivers. Further, the effects of some extinction drivers are currently poorly understood and therefore difficult to predict (e.g. climate change) and it may be premature to dismiss the predictions of random scenarios as irrelevant to all real examples of species loss. The first generations of biodiversity experiments have provided valuable, and sometimes unexpected, discoveries about the general nature of the relationship between diversity and ecosystem functioning. These discoveries could not have been made using observational studies. We propose that different examples of extinction loss in the real or a potential future world form a continuum from situations where the results of the first-generation biodiversity experiments will be highly relevant to less relevant. At the one extreme are examples where the effects of biodiversity on ecosystem functioning will be overwhelmed by direct effects of the extinction driver on processes (e.g. chronic eutrophication). At the other extreme are situations where ecosystem processes are not strongly affected by direct effects of the extinction driver and where the effects of species loss on functioning may be more important (e.g. habitat fragmentation). Given the unprecedented uncertainty about the future of biodiversity and the functioning of ecosystems, a general approach with randomly varying species pools was the right place to start in order to provide a general foundation. The new challenge is to test for effects of biodiversity on functioning in real-world examples of species loss.

Zusammenfassung

Biodiversitätsversuche zeichnen sich dadurch aus, dass natürliche Artenpools experimentell reduziert werden und anschließend der Zusammenhang zwischen der Artenzahl und Ökosystemfunktionen unter konstanten abiotischen Umweltbedingungen untersucht wird. Dadurch unterscheiden sich Biodiversitätsexperimente grundsätzlich von anderen Versuchen, die die Biodiversität als Zielvariable behandeln und stattdessen die abiotische Umwelt manipulieren. Die Auswahl der Arten für die reduzierten Artenpools in Biodiversitätsexperimenten erfolgte bisher meist zufällig, während natürliche Aussterbefaktoren wie Eutrophierung nicht alle Arten gleichermassen gefährden. Für verschiedene Aussterbefaktoren ist aber so wenig bekannt, dass ein zufälliges Aussterbeszenario die beste gegenwärtig verfügbare Option ist. Dies trifft insbesondere für mögliche zukünftige Aussterbeprozesse zu, die durch globale Umweltveränderungen (Klima, biologische Invasionen) oder Habitatsfragmentierung ausgelöst werden könnten. Die erste Generation von Biodiversitätsexperimenten mit zufälligen Aussterbeszenarien hat wertvolle, teilweise unerwartete, generelle Zusammenhänge zwischen Artenzahl und Ökosystemfunktionen aufgedeckt. Diese Zusammenhänge ließen sich durch vergleichende Studien nicht erkennen. In Zukunft sollten Biodiversitätsexperimente dennoch vermehrt Aussterbeszenarien simulieren, die in der realen Umwelt mit größter Wahrscheinlichkeit auftreten.     

Merging aquatic and terrestrial perspectives of nutrient biogeochemistry

Although biogeochemistry is an integrative discipline, terrestrial and aquatic subdisciplines have developed somewhat independently of each other. Physical and biological differences between aquatic and terrestrial ecosystems explain this history. In both aquatic and terrestrial biogeochemistry, key questions and concepts arise from a focus on nutrient limitation, ecosystem nutrient retention, and controls of nutrient transformations. Current understanding is captured in conceptual models for different ecosystem types, which share some features and diverge in other ways. Distinctiveness of subdisciplines has been appropriate in some respects and has fostered important advances in theory. On the other hand, lack of integration between aquatic and terrestrial biogeochemistry limits our ability to deal with biogeochemical phenomena across large landscapes in which connections between terrestrial and aquatic elements are important. Separation of the two approaches also has not served attempts to scale up or to estimate fluxes from large areas based on plot measurements. Understanding connectivity between the two system types and scaling up biogeochemical information will rely on coupled hydrologic and ecological models, and may be critical for addressing environmental problems associated with locally, regionally, and globally altered biogeochemical cycles.We dedicate this paper to the memory of Catherine Lisa Dent, a member of our working group who contributed much to the ideas presented herein, and to the joy of developing them together.Due to an error in the citation line, this revised PDF (published in December 2003) deviates from the printed version, and is the correct and authoritative version of the paper.     

Marine biodiversity and ecosystem services: an elusive link

Efforts to test the hypothesised positive link between ecosystem services and functions and biodiversity are increasing in order to forecast the consequences of the present erosion of biodiversity on ecosystem functions and to provide an additional basis for the conservation of biodiversity. These efforts have been, however, modest in marine ecosystems. An examination of seagrass communities, which are simple assemblages with a limited membership of about 50 species worldwide and <12 species in any one community, provides, however, strong evidence for the existence of such positive link between species richness and ecosystem functions. Ecosystem functions are, however, dependent on the particular membership of the community, rather that its number, for the functions are species-specific properties. Yet evidence, is provided, that an increasing species richness should be, on average, linked to an increase in the functional repertoire present in the community, will lead to a more efficient use of resources and a greater capacity to ensure the sustainability of ecosystem functions under disturbance or ecosystem change. Closer examination indicates that the functional variability of mixed-species seagrass assemblages is correlated to the variability in species size, whereas species of similar size tend to show similar functional capacities and, therefore, a greater degree of functional redundancy. In addition, the demonstration of positive interactions in seagrass communities, which are also dependent on the presence of engineering species in the community that facilitate the growth of other species, provides increasing grounds to expect an enhanced functional performance of mixed communities over that expected from a simple additive contribution of the community members. Multispecific communities also hold, within the functional repertoire they contain, many unrealised functional potentials that may prove instrumental to ensure the sustainability of ecosystem functions in the presence of disturbance or a changing environment. The arguments offered, illustrated for the comparatively simple seagrass communities, provide strong reasons to expect a strong — if difficult to test experimentally — positive relationship between species diversity and the functions of marine ecosystems and, thereby, the services they yield to humanity.     

Comparative analyses in aquatic microbial ecology: how far do they go?

Methodological developments in recent years have led to an increase in empirical databases on the abundance and functions of aquatic microbes, now allowing synthesis studies. Most of these studies have adopted a comparative approach, such that comparative analyses are now available for most aspects of aquatic microbial food webs (more than 50 papers published in the last 15 years). Some of these analyses apparently yield conflicting results, introducing confusion and unnecessary disputes in the field. We briefly review the comparative analyses so far produced and we highlight generalities, show that some of the perceived discrepancies largely derive from partial analyses of a general underlying trend and formulate predictions based on these general trends that provide new avenues for research.