Structural implications of traditional agricultural landscapes on the functional diversity of birds near the Korean Demilitarized Zone

Predicting avian diversity based on land use and cover on a national scale

This study explores the relationship between landscape features and avian diversity in South Korea, examining both taxonomic and functional diversity. The Korean Peninsula serves as a pivotal habitat for resident bird species and a migratory pathway in the East Asia-Pacific flyway. Using a national dataset with block sizes ranging from 3.5 to 4.5 kilometers per side, we found that less urbanized open plains exhibit higher taxonomic diversity, while coastal regions with diverse water bird populations show higher functional diversity. These findings underscore the significance of conserving the existing land types and qualities in specific regions to substantially impact bird distribution and regional biodiversity. Remarkably, closed forests display diversity patterns akin to urban/built-up areas, despite their disparate land use characteristics. The stability of bird diversity indices across different land use types enables us to predict bird diversity indices based on the particular land use and land cover configurations. This study emphasizes the complementary nature of functional biodiversity indices in comprehending bird distribution patterns alongside taxonomic diversity indices.

Functional group analyses of herpetofauna in South Korea using a large dataset

Functional traits are characteristics of species that affect their fitness and ecosystem, and they greatly influence ecological niches. Thus, biodiversity assessment based on functional groups rather than species per se can more realistically reflect the ecological niche space. As essential players of ecosystem functions, herpetofauna are appropriate subjects of functional trait-based analyses. In this study, using a nationwide dataset and applying trait information and ecological niche modeling, the richness within each functional group, and the taxonomic and functional diversity indices of South Korean herpetofauna were visualized to identify and compare the geographic distributions. The results revealed that the reptile community seemed more locally diverse with more overlapping randomized patterns among groups than amphibians, while amphibians showed wider distributions and a higher within-grid occurrence ratio. Functional diversity indices of reptiles also showed more randomized geographic patterns with higher levels at Jejudo Island than amphibians. The findings of this study may help to identify biodiversity hot spots and understand its ecosystem health. Increasing survey data and trait information will improve the assessment.

Fish Diversity and Ichthyofauna of Areas Adjacent to the Demilitarized Zone in South Korea

The Korean Demilitarized Zone (DMZ) was established in 1953 during the cessation of the Korean War, which divided the Korean Peninsula into North and South Korea. The DMZ is a representative biodiversity resource because it limits human activities. The current status of faunal diversity in adjacent areas of the DMZ was investigated in five regions at 91 sites from 2015 to 2019. A total of 19,562 individuals were collected and identified, including 81 species, 19 families, and 11 orders. Zacco koreanus was the most abundant fish species (relative abundance of 21.9%), while other key species were Zacco platypus (18.2%), Rhynchocypris oxycephalus (5.2%), Rhynchocypris steindachneri (4.9%), and Pungtungia herzi (3.7%). Notably, twenty-nige endemic and seven Red Data Book species were recorded, and three exotic species, Carassius cuvieri, Micropterus salmoides, and Lepomis macrochirus were found at five sites. Human activities and disturbances were found at 34.0% of all sampling sites, and the highest disturbance factors were river dredging and agricultural use (seven sites), sewage (five sites), and fisheries and development (two sites). We recommend that the governments of South and North Korea collaboratively manage the DMZ to protect ecological diversity and maintain its status as a symbol of peace.

The contribution of landscape features, climate and topography in shaping taxonomical and functional diversity of avian communities in a heterogeneous Alpine region

Understanding the effects of landscape composition and configuration, climate, and topography on bird diversity is necessary to identify distribution drivers, potential impacts of land use changes, and future conservation strategies. We surveyed bird communities in a study area located in the Central Alps (Autonomous Province of South Tyrol, northeast Italy), by means of point counts and investigated taxonomic and functional diversity at two spatial scales along gradients of land use/land cover (LULC) intensity and elevation. We also explored how environmental variables influence bird traits and red-list categories. Models combining drivers of different types were highly supported, pointing towards synergetic effects of different types of environmental variables on bird communities. The model containing only LULC compositional variables was the most supported one among the single-group models: LULC composition plays a crucial role in shaping local biodiversity and hence bird communities, even across broad landscape gradients. Particularly relevant were wetlands, open habitats, agricultural mosaics made up of small habitat patches and settlements, ecotonal and structural elements in agricultural settings, and continuous forests. To conserve bird diversity in the Alps, planning and management practices promoting and maintaining small fields, structural elements, and a mosaic of different LULC types should be supported, while preserving continuous forests at the same time. Additionally, pastures, extensively used meadows, and wetlands are key to conservation. These strategies might mitigate the impacts of global change on bird diversity in the Alps and in other European mountain areas.

Bird Functional Diversity in Agroecosystems and Secondary Forests of the Tropical Andes

Agricultural systems have increased in extension and intensity worldwide, altering vertebrate functional diversity, ecosystem functioning, and ecosystemic services. However, the effects of open monoculture crops on bird functional diversity remain little explored, particularly in highly biodiverse regions such as the tropical Andes. We aim to assess the functional diversity differences of bird guilds between monoculture crops (coffee, cocoa, and citrus) and secondary forests. We use four functional diversity indices (Rao Q, Functional Richness, Functional Evenness, and Functional Divergence) related to relevant morphological, life history, and behavioral traits. We find significant differences in functional diversity between agroecosystem and forest habitats. Particularly, bird functional diversity is quite homogeneous among crop types. Functional traits related to locomotion (body weight, wing-chord length, and tail length), nest type (closed), and foraging strata (canopy and understory) are dominant at the agroecosystems. The bird assemblages found at the agroecosystems are more homogeneous in terms of functional diversity than those found at the secondary forests, as a result of crop structure and management. We recommend promoting more diverse agroecosystems to enhance bird functional diversity and reduce their effects on biodiversity.

Long-Term Land Cover Changes in the Western Part of the Korean Demilitarized Zone

After the Korean War, human access to the Korean Demilitarized Zone (DMZ) was highly restricted. However, limited agricultural activity was allowed in the Civilian Control Zone (CCZ) surrounding the DMZ. In this study, land cover and vegetation changes in the western DMZ and CCZ from 1919 to 2017 were investigated. Coniferous forests were nearly completely destroyed during the war and were then converted to deciduous forests by ecological succession. Plains in the DMZ and CCZ areas showed different patterns of land cover changes. In the DMZ, pre-war rice paddies were gradually transformed into grasslands. These grasslands have not returned to forest, and this may be explained by wildfires set for military purposes or hydrological fluctuations in floodplains. Grasslands near the floodplains in the DMZ are highly valued for conservation as a rare land type. Most grasslands in the CCZ were converted back to rice paddies, consistent with their previous use. After the 1990s, ginseng cultivation in the CCZ increased. In addition, the landscape changes in the Korean DMZ and CCZ were affected by political circumstances between South and North Korea. Our results provide baseline information for the development of ecosystem management and conservation plans for the Korean DMZ and CCZ. Given the high biodiversity and ecological integrity of the Korean DMZ region, transboundary governance for conservation should be designed.

Effect of the Human Utilization of Northern Snakehead (Channa argus Cantor, 1842) on the Settlement of Exotic Fish and Cladoceran Community Structure

Empirical studies suggest that changes in the density of top predators, such as carnivorous fish, in freshwater food webs, strongly affect not only fish communities but also various primary and secondary consumers. Based on these findings, we explored how differences in the utilization of carnivorous fish (i.e., Northern Snakehead, Channa argus) by humans affected the fish and cladoceran community structure as well as the settlement of exotic fish species (i.e., Lepomis macrochirus and Micropterus salmoides) in 30 wetlands located in the upper and lower reaches of the Nakdong River. Our results show that in the mid–lower reaches of the Nakdong River, the density of C. argus was low, while high densities of L. macrochirus and M. salmoides were observed. Exotic fish species are frequently consumed by C. argus, leading to a low density of L. macrochirus and M. salmoides in the upper reaches, which supported a high density of C. argus. However, in the mid–lower reaches, the density of L. macrochirus was high because of the frequent collection of C. argus by fishing activities. The dominance of L. macrochirus significantly changed the structure of cladoceran communities. L. macrochirus mainly feeds on pelagic species, increasing the density of epiphytic species in the mid–lower reaches. The continued utilization of C. argus by humans induced a stable settlement of exotic fish species and strongly affected the community structures of primary consumers in the 30 wetlands. The frequency of C. argus collection has to be reduced to secure biodiversity in the mid–lower reaches of the Nakdong River, which will reduce the proportion of exotic fish species and increase the conservation of native fish.