Climate and topography drives macroscale biodiversity through land‐use change in a human‐dominated world

Abstract

Drivers of biodiversity at macroscales have long been of interest in ecology, and climate and topography are now considered to be major drivers. Because humans have transformed most of the Earth's land surface, land use may play a significant role as a driver of biodiversity at a macroscale. Here we disentangle the relationships among climate, topography, land use, available energy (measured by the normalized difference vegetation index [NDVI]), and species richness of Japanese forest birds. Species richness was better explained at 40‐ and 80‐km resolutions than at 5‐, 10‐ and 20‐km resolutions; it was explained by climate, topography, and land use, and the effects of land use were fully incorporated into those of climate and topography. As temperature increased and elevation decreased, natural forest area decreased, and this decrease intensified in warm lowland areas. With the loss of natural forest, species richness decreased below a certain threshold. As temperature increased and elevation decreased, species richness and NDVI increased slightly or were unchanged in cool highland areas and decreased in warm lowland areas. Species richness increased linearly with the increase in NDVI. Most effects of climate/topography on species richness in warm lowland areas were shared by those of land use, suggesting that the decrease in species richness in warm lowland areas has been caused by loss of natural forest. Therefore, it is suggested that climate and topography determined land use intensity, which in turn, drove species richness through the depletion of available energy. Increasing temperature and decreasing elevation leads to both benefits (increase in potential available energy) and costs (depletion of energy by human land‐use change) for forest birds. These costs seem to override benefits in warm lowland areas.

A review of post-war changes in rice farming and biodiversity in Japan

“…Japan has a wide topographic gradient (the landscape ranges from high mountains to coastal plains; Yamaura et al, 2011), and its land is mainly covered by forests (68.5% of the land area) and agricultural areas (12.6%; FAO, 2013). The major crop is rice, accounting for 48.4% of the total cultivated area (Statistics Bureau, 2013a).…”

Disentangling the effects of environmental factors on the distribution of vascular plants in Japan: the importance of land use for common species on a macroscale

“…Different LU activities affect the distribution of a wide variety of organisms, including plants, and induce various changes in the habitats and vegetation (e.g. Virkkala et al 2005;Kivinen et al 2007;Yamaura et al 2011;Saito and Koike 2013).…”

Identifying priority areas for national-level conservation to achieve Aichi Target 11: A case study of using terrestrial birds breeding in Japan

“…The transects (3 km long) were established such that two transects were included in every 20 km grid section in Japan, and total censuses including questionnaire covered 61% of the national land area. Bird records were ranked by estimated breeding status (four ranks: A-D; for more detail, see Yamaura, Amano, Kusumoto, Nagata, & Okabe, 2011). To include rare species, the major conservation targets, we used both transect surveys and questionnaire data, treating all species as presence-only data.…”