Taku Kadoya

National Institute for Environmental Studies

Recent studies have revealed that biotic interactions in ecological communities vary over time, possibly mediating community responses to anthropogenic disturbances. This study investigated the heterogeneity of such variability within a real community and its impact on population stability in the face of pesticide application, particularly focusing...

Elucidating biodiversity patterns and their background processes is critical in biodiversity science. Dissimilarity, which is calculated based on multivariate biological quantities, is a major component of biodiversity. As spatial and temporal biodiversity information availability increases, the scope of dissimilarity studies has been expanded to c...

Recent studies have revealed that biotic interactions in ecological communities vary over time, possibly mediating community responses to anthropogenic disturbances. This study investigated the heterogeneity of such variability within a real community and its impact on population stability in the face of pesticide application, particularly focusing...

Long‐term monitoring of forest tree communities is a basis for elucidating forest structure and dynamics and for evaluating ecosystem functions such as primary production. Because global climate change is changing forest ecosystems from the local to the global scale, it is essential to document long‐term monitoring data of forests to examine the te...

In summer, the survival zones of cold‐water species are predicted to narrow by both increasing water temperatures from the surface and by expanding hypoxic zones from the lake bottom. To examine how the abundance of cold‐water fishes changes along environmental gradients, we assessed the vertical environmental DNA (eDNA) distributions of three salm...

Aim Environmental change affects metacommunity structure both directly—via abiotic factors and dispersal that affect species occurrence—and indirectly—via complex interactions among co‐occurring species. We examined how the three main metacommunity factors—environmental conditions, spatial processes and species associations—affect metacommunity str...

Systemic insecticides are one of the causes of Odonata declines in paddy fields. Since rising temperatures associated with global warming can contribute to strengthen pesticide toxicity, insecticide exposures under increasing temperatures may accelerate the decline of Odonata species in the future. However, the combined effects of multiple stressor...

Anthropogenic noise is ubiquitous globally. However, we know little about how the impacts of noise alter fundamental ecosystem properties, such as resource consumption by invertebrate consumers. Using experimental noise manipulation and faecal DNA metabarcoding, we assessed how the direct and cross‐trophic indirect effects of noise altered the diet...

As interest in natural capital grows and society increasingly recognizes the value of biodiversity, we must discuss how ecosystem observations to detect changes in biodiversity can be sustained through collaboration across regions and sectors. However, there are many barriers to establishing and sustaining large-scale, fine-resolution ecosystem obs...

Assessing the vulnerability and adaptive capacity of species, communities, and ecosystems is essential for successful conservation. Climate change, however, induces extreme uncertainty in various pathways of assessments, which hampers robust decision-making for conservation. Here, we developed a framework that allows us to quantify the level of acc...

Amami‐Oshima and Tokunoshima Islands (the Amami Islands) are part of an important area for biogeography in Japan. Although the uniqueness of the islands' flora is well recognized, their plant diversity, including non‐tree life forms, has yet to be compared with that of other regions. Here, we characterize the plant community structure of the Amami...

Water‐level drawdowns are a management option for improving water quality in shallow, eutrophic lakes, but how much water levels should be reduced and what abiotic and biotic mechanisms can be expected to reduce the adverse effects of eutrophication are unclear. We conducted a study with two experimental pools (10 m wide, 30 m long, and approx. 2.5...

Elucidating biodiversity patterns and their background processes is critical in biodiversity science. Dissimilarity, which is calculated based on multivariate biological quantities, is a major component of biodiversity. As spatial and temporal biodiversity information availability increases, the scope of dissimilarity studies has been expanded to c...

This data paper presents the vascular plant biodiversity sampled from four plots on Amami‐Oshima Island, three plots on Tokunoshima Island, and one plot on Okinawa Island within the natural World Heritage site, and an additional three plots in southern Kyushu using the standardized belt‐transect survey method during July 2012 to October 2020. The d...

Forest disturbance, including deforestation, is a major driver of global biodiversity decline. Identifying the underlying socioeconomic drivers can help guide interventions to halt biodiversity decline. Here, we quantified spatial overlaps between the distributions of 6164 globally threatened terrestrial vertebrate species and five major forest dis...

Although long-term ecosystem monitoring provides essential knowledge for practicing ecosystem management, analyses of the causal effects of ecological impacts from large-scale observational data are still in an early stage of development. We used causal impact analysis (CIA)—a synthetic control method that enables estimation of causal impacts from...

Biological atlas data can be used as inputs into conservation decision-making, yet atlases are sometimes infrequently updated, which can be problematic when the distribution of species is changing rapidly. Despite this, we have a poor understanding of strategies for efficiently updating biological atlas data. Using atlases of the distributions of 1...

We present the largest freely available EcoPlate dataset for Japan, comprising data collected from a network of 33 natural forest sites (77 plots) in regions of East Asia ranging from cool temperate to subtropical. EcoPlate is a 96‐well microplate that contains three repeated sets of 31 response wells with different sole carbon substrates. The util...

The direction and magnitude of species distribution shifts tend to differ among species and functional types (FTs). Quantifying functional trait variation and species interactions will improve our understanding of the complex mechanisms that govern ecosystem dynamics and their responses to climate change. Here, we analyzed differences in the juveni...

Significance Larger ecosystems support more species; this ubiquitous pattern is the foundation of current conservation schemes. However, many ecosystems possess a complex spatial structure that cannot be represented by area, and the role of such complexity in regulating biodiversity patterns is largely unknown. Here, we use theory and extensive fis...

Environmental DNA (eDNA) metabarcoding has become widely applied to gauge biodiversity in a non‐invasive and cost‐efficient manner. The detection of species using eDNA metabarcoding is, however, imperfect owing to various factors that can cause false negatives in the inherent multistage workflow. Imperfect detection in the multistage workflow of eD...

1. To be effective, the next generation of conservation practitioners and managers need to be critical thinkers with a deep understanding of how to make evidence-based decisions and of the value of evidence synthesis. 2. If, as educators, we do not make these priorities a core part of what we teach, we are failing to prepare our students to make an...

Larger ecosystems support more species; this ubiquitous pattern is the foundation of current conservation schemes. However, many ecosystems possess a complex spatial structure that cannot be represented by area, and the role of such complexity in scaling biodiversity is largely unknown. Here, we use theory and extensive fish community data from two...

The global transition to renewable energy sources has accelerated to mitigate the effects of global climate change. Sudden increases in solar power facilities have caused the physical destruction of wildlife habitats, thereby resulting in the decline of biodiversity and ecosystem functions. However, previous assessments have been based on the envir...

Environmental DNA (eDNA) metabarcoding has become widely applied to gauge biodiversity in a noninvasive and cost-efficient manner. The detection of species using eDNA metabarcoding is, however, imperfect owing to various factors that can cause false negatives in the inherent multi-stage workflow. Imperfect detection in the multi-stage workflow of e...

It has been observed that market failure has hampered the development of sustainable forest ecosystem services such as CO2 absorption and fixation, water retention, and biodiversity. One of the reasons for this is that the link between forest land use and the beneficiaries of that use has not been widely recognized or clearly established. To addres...

1. To be effective, the next generation of conservation practitioners and managers need to be critical thinkers with a deep understanding of how to make evidence‐based decisions and of the value of evidence synthesis. 2. If, as educators, we do not make these priorities a core part of what we teach, we are failing to prepare our students to make an...

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Although dragonflies are excellent environmental indicators for monitoring terrestrial water ecosystems, automatic monitoring techniques using digital tools are limited. We designed a novel camera trapping system with an original dragonfly detector based on the hypothesis that perching dragonflies can be automatically detected using inexpensive and...

Climate warming is of concern as a key factor in the worldwide decline in insect populations. In Japan, numbers of a common dragonfly in rice paddy fields, Sympetrum frequens, decreased sharply in the 1990s. Because S. frequens migrates to cooler mountains in summer, climate warming has been suggested as one of the main causes of the population dec...

Aim Climate variability threatens to destabilize production in many ecosystems. Asynchronous species dynamics may buffer against such variability when a decrease in performance by some species is offset by an increase in performance of others. However, high climatic variability can eliminate species through stochastic extinctions or cause similar s...

Noise pollution is pervasive across every ecosystem on Earth. Although decades of research have documented a variety of negative impacts of noise to organisms, key gaps remain, such as how noise affects different taxa within a biological community and how effects of noise propagate across space. We experimentally applied traffic noise pollution to...

Spatial heterogeneity of landscapes is a key factor for the diversity of biota. There are a rich variety of agricultural landscapes around the globe that differ with respect to composition and spatial configuration of land-use types, reflecting different levels of human impacts. To test whether landscape structure influences biodiversity in similar...

Ecological niche models (ENMs) are widely used in spatial prioritization for biodiversity conservation (e.g. selecting conservation areas). However, it is unclear whether ENMs are always beneficial for such purposes. We quantified the benefit of using ENMs in conservation prioritization, comparing the numbers of species covered by conservation area...

Agriculture faces the great challenge of developing strategies to maintain production while simultaneously reducing environmental impacts. The trade‐off between crop production and water quality services is one of the most serious issues facing agriculture, and interest in achieving win–win outcomes through management of ecosystem services is growi...

Globally, lake fish communities are being subjected to a range of scale‐dependent anthropogenic pressures, from climate change to eutrophication, and from over‐exploitation to species introductions. As a consequence, the composition of these communities is being reshuffled, in most cases leading to a surge in taxonomic similarity at the regional sc...

The effects of environmental seasonality on food web structure have been notoriously understudied in empirical ecology. Here, we focus on seasonal changes in one key attribute of a food web, consumer trophic position. We ask whether fishes inhabiting tropical river–floodplain ecosystems behave as seasonal omnivores, by shifting their trophic positi...

Conservation planning has generally used models with a static spatial distribution of species to predict the likely occurrence of species. However, static data do not usually capture rapid changes in the abundance of endangered species or cryptic life stages such as the dormancy stage of eggs and seeds. Little is known about how neglecting dynamic...

Provisioning is a basic forest ecosystem service, and the balance between human usage and natural resources that provide this service is crucial for sustainability. Here, we describe a spatial mismatch between monetaryequivalent production (actual use of this service) and the estimated potential supply of edible and medicinal wild plants in Japan,...

Food web theory suggests that the placement of a weak interaction is critical such that under some conditions even one well‐placed weak interaction can stabilise multiple strong interactions. This theory suggests that complex stable webs may be built from pivotal weak interactions such that the removal of even one to a few keystone interactions can...

Nutrient supply is a key bottom‐up control of phytoplankton primary production in lake ecosystems. Top‐down control via grazing pressure by zooplankton also constrains primary production, and primary production may simultaneously affect zooplankton. Few studies have addressed these bidirectional interactions. We used convergent cross‐mapping (CCM),...

Anthropogenic noise is widespread, and growing evidence suggests that it can negatively affect animals through many different mechanisms including masking of cues and signals, distraction, and aversion to noise. Acoustic masking has received the most attention from researchers and recent evidence suggests that masking effects can be mitigated by al...

Species richness is regulated by a complex network of scale-dependent processes. This complexity can obscure the influence of limiting species interactions, making it difficult to determine if abiotic or biotic drivers are more predominant regulators of richness. Using integrative modeling of freshwater fish richness from 721 lakes along an 11olati...

The larval and adult stages of amphibious animals are affected by both aquatic and terrestrial habitat characteristics, and each stage also affects the other. However, this link between life stages has been largely overlooked in previous studies. We examined the effect of aquatic and terrestrial habitat characteristics on the diversity of larval an...

Land-use/land-cover heterogeneity is among the most important factors influencing biodiversity in agricultural landscapes and is the key to the conservation of multi-habitat dwellers that use both terrestrial and aquatic habitats. Heterogeneity indices based on land-use/land-cover maps typically do not integrate ecological dissimilarity between lan...

Biodiversity loss can be accelerated by human consumption in regions that are far removed from habitat degradation because of economic globalization, but no study has directly quantified the effects of global trade on extinction risks at a global scale with consideration for species differences. We propose a novel biodiversity footprint index based...

Small lentic water bodies such as agricultural ponds, mire pools, floodplain pools, oxbow lakes, and lagoons around lakes play important roles in the conservation of biodiversity in terms of providing important habitats to wildlife. A geographical information system (GIS) was applied to infer the spatial distribution and relative abundance of small...

Protected areas spearhead global conservation efforts, but it has been repeatedly demonstrated that narrowly distributed species are more likely to be unrepresented in protected areas. This means that where local extinctions are more likely outside protected areas, a positive feedback loop could render protected areas largely ineffective in deceler...

Theory suggests that bottom-up effects of resource diversity to upper trophic levels increases ecosystem functioning. In particular, energy flux from the detritus to other organisms in an ecosystem affects food web dynamics. To our knowledge, no empirical studies have examined how detritivore diversity alters the energy flux to upper trophic levels...

Land use data serve as an essential part of large-scale ecological research, such as landscape ecology and macroecological studies. For agricultural fields in Japan, existing time series statistical records can be used to convert map data according to a map of municipality units. In this data paper, we determined the areas of agricultural land use...

Food web theory states that a weak interactor which is positioned in the food web such that it tends to deflect, or mute, energy away from a potentially oscillating consumer-resource interaction often enhances community persistence and stability. Here we examine how adding other weak interactions (predation/harvesting) on the stabilizing weak inter...

Forest cover loss is a major cause of both the decline in global biodiversity and the increase in carbon emissions into the atmosphere. Focusing on the effects of logging, this study introduces an index of wood production, the forest harvest index (FHI), which calculates the expected gross forest cover loss (GFCL) reflecting the demand for timber a...

After the reversion of Okinawa (Ryukyu Islands) to Japan in 1972, extensive urban and agricultural development resulted in a significant increase in sediment discharge to coastal waters. The release of sediment has caused the degradation of freshwater and coastal ecosystems and biodiversity. A consideration for catchment-to-reef continua, as well a...

Although many studies have focused on marine resources, few studies have considered the resources of inland fisheries. Inland fishery resources are typically either monitored on the basis of catch data alone or are not assessed quantitatively at all, despite their social, economic, and ecological importance. Because freshwater ecosystems have been...

Mangrove plants, which develop highly productive forests on tropical–subtropical coastlines and river estuaries, rely mainly on river and sea water currents for their diaspore dispersal. Mangrove diaspores are basically dispersed in brackish to sea waters; thus whether they sink or float during the dispersal period could be changed dynamically, bot...

Background/Question/Methods Many vascular plants are threaten by various drivers such as land use change and overpopulated herbivores. More than 500 citizen botanists have archived quantitative information on population size and changing rate of population size for 1618 Japanese plant taxa twice (1994-1995 and 2003-2004). Those surveys enable us to...

Background/Question/Methods Theory suggests that bottom-up effects of resource diversity to upper trophic levels increase ecosystem stability. In particular, energy flux from the detritus to an ecosystem stabilizes food web dynamics. To our knowledge, no empirical studies have examined how detritivore diversity alters the energy flux to upper tro...

Background/Question/Methods Although many studies have focused on marine resources, fewer studies have considered inland fishery resources. Inland fishery resources are typically monitored on the basis of catch data alone or are not assessed quantitatively, despite their social, economic, and ecological importance. Because freshwater ecosystems ha...

Although many people have expressed alarm that we are witnessing a mass extinction, few projections have been quantified, owing to limited availability of time-series data on threatened organisms, especially plants. To quantify the risk of extinction, we need to monitor changes in population size over time for as many species as possible. Here, we...

Propagule pressure and habitat characteristics are important factors used to predict the distribution of invasive alien species. For species exhibiting strong propagule pressure because of human-mediated introduction of species, indicators of introduction potential must represent the behavioral characteristics of humans. This study examined 64 agri...

One of the promising approaches to monitoring biodiversity is assessing the status of pressures driving the biodiversity state. To achieve this, we need to identify the principal pressures that cause simultaneous biodiversity loss across taxonomic groups and clarify how multiple pressures act synergistically or at least simultaneously to decrease b...

Land-use/cover data are essential to estimate biodiversity and ecosystem services. Although many data and maps have been produced in Japan, there is significant variation in their characteristics, such as publication year, spatial resolution, and land-use/cover classification categories because the purposes of the data and maps differ (e.g., resour...

The involvement of a wide range of stakeholders in conservation actions is essential for achieving lasting conservation efforts at a large spatial scale. This issue was one primary focus of the Aichi Biodiversity Target endorsed at the COP10 of the Convention on Biological Diversity. Citizen participation is particularly important given the potenti...

Local aggregations of unionoids (mussel beds) represent subpopulations constituting a riverine meta-population and are presumed to be linked by dispersal of parasitic mussel larvae (glochidia) on host fishes. We examined movement patterns of Masu Salmon (Oncorhynchus masou masou), the obligate host fish for the freshwater pearl mussel Margaritifera...

The spatial prioritization of biodiversity restoration sites on a national scale lags behind that of protected areas. We present a simple framework for spatial restoration prioritization using complementarity analysis based on the differences between past and present species distributions and restoration feasibility. In the framework, sites that we...

To be effective in biodiversity conservation, spatial conservation planning should consider the complementarity among planning units. Complementarity is one of the central concepts in spatial conservation prioritization, and complementarity analysis based on the concept is becoming a major method both in research and in practice dealing with spatia...

To overview Satoyama biodiversity in Japan, we classified and mapped national land use into the categories "wilderness land use," "rural land use," "plantation," and "urban land use" using a high-resolution (50-m grid) land-use map. We also mapped the modified Satoyama index (M-SI), defined as the Simpson's diversity index of land-use types within...

Changes in land use and land cover are among the most important effects on biodiversity. Therefore, accurate classification of land cover and land use, with sufficient spatial and temporal resolution, is essential for assessing the state of biodiversity over large spatial scales and changes over time. However, no comprehensive national land-use map...

Satoyama is a rural landscape consisting of a diverse mosaic of agricultural and nonagricultural land that provides suitable habitats not only for habitat specialists but also for multi-habitat dwellers. In the present study, we examined land-cover data at an appropriate combination of spatial scale and resolution, to calculate a land-cover heterog...