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Shiono, T.

Publications and source records attributed to Shiono, T..

3 recordsLinked to original sources

Occurrence-based diversity estimation reveals macroecological and conservation knowledge gaps for global woody plants

Incomplete sampling of species geographic distributions has challenged biogeographers for many years to precisely quantify global-scale biodiversity patterns. After correcting for the spatial inequality of sample completeness, we generated a global species diversity map for woody angiosperms (82,974 species, 13,959,780 occurrence records). The estimated diversity demonstrated non-linear latitudinal and longitudinal patterns that were potentially related to region-specific biogeographic factors including current climate, paleoclimate, and topographical factors, while energy availability was the most important predictor at a global level. We identified the areas with potentially high species richness and rarity, but poorly explored, unprotected, and threatened by deforestation: they are distributed mostly at low latitudes across central South America, central Africa, subtropical China, and Indomalayan islands. These priority areas for botanical exploration would help to efficiently fill spatial knowledge gaps for better describing the status of biodiversity and improve the effectiveness of the protected area network for global woody plant conservation. TeaserBias-corrected diversity map based on occurrence records sheds new light on global macroecology and conservation of woody angiosperms.

ecology↗

Area-based conservation planning in Japan: protected area network effectiveness to the post-2020 Global Biodiversity Framework

To reframe the imperfect review processes of nation-scale actions on area-based conservation through protected area (PA) networks, we first created novel infrastructure to visualize nation-level biodiversity information in Japan. We then assessed the performance of the existing PA network relative to land exploitation pressure and evaluated conservation effectiveness of PA expansion for the post-2020 Global Biodiversity Framework. The Zonation algorithm was used to spatially prioritize conservation areas to minimize biodiversity loss and the extinction risk for 8,500 Japanese vascular plant and vertebrate species under constraints of the existing PA network and land use. The spatial pattern of the identified priority areas, which were considered candidate areas for expansion of the current PA network, was influenced by land-use types according to the mask layers of non-PAs, and low-, middle-, and high-ranked PAs. The current PA network reduced the aggregate extinction risk of multiple species by 36.6%. Indeed, the percentage of built-up areas in the existing PAs was in general smaller than that in the areas surrounding PAs. Notably, high-ranked PAs fully restrained built-up pressure (0.037% per 10 years), whereas low-ranked PAs in the national park and wild-life protection areas did not (1.845% per 10 years). Conservation effects were predicted to substantially improve by expansion of high-ranked (legally strict) PAs into remote non-PAs without population/socio-economic activities, or expansion of medium-ranked PAs into agriculture forestry satoyama and urban areas. A 30% land conservation target was predicted to decrease extinction risk by 74.1% when PA expansion was implemented across remote areas, satoyama, and urban areas; moreover, PA connectivity almost doubled compared with the existing PA network. In contrast, a conventional scenario showed that placing national parks in state-owned and non-populated areas would reduce extinction risk by only 4.0%. The conservation prioritization analyses demonstrated an effectiveness of using a comprehensive conservation approach that reconciles land-sparing protection and land-sharing conservation in other effective area-based conservation measures (OECM) in satoyama and urban green spaces. Our results revealed that complementary inclusion of various PAs interventions related to their governance and land-use planning plays a critical role in effectively preventing biodiversity loss and makes it more feasible to achieve ambitious conservation targets.

ecology↗

Macroscale estimates of species abundance reveal evolutionary drivers of biodiversity

Evolutionary processes underpin the biodiversity on the planet. Theories advocate that the form of the species abundance distribution (SAD), presented by the number of individuals for each species within an ecological community, is intimately linked to speciation modes such as point mutation and random fission. This prediction has rarely been, however, verified empirically; the fact that species abundance data can be obtained only from local communities critically limits our ability to infer the role of macroevolution in shaping ecological patterns. Here, we developed a novel statistical model to estimate macroscale SADs, the hidden macroecological property, by integrating spatially replicated multispecies detection-nondetection observations and the data on species geographic distributions. We determined abundance of 1,248 woody plant species at a 10 km grid square resolution over East Asian islands across subtropical to temperate biomes, which produced a metacommunity (i.e. species pool) SAD in four insular ecoregions along with its absolute size. The metacommunity SADs indicated lognormal-like distributions, which were well explained by the unified neutral theory of biodiversity and biogeography (UNTB) with protracted speciation, a mode of speciation intermediate between point mutation and random fission. Furthermore, the analyses yielded an estimate of speciation rate in each region that highlighted the importance of geographic characteristics in macroevolutionary processes and predicted the average species lifetime that was congruent with previous estimates. The estimation of macroscale SADs plays a remarkable role in revealing evolutionary diversification of regional species pools.

ecology↗