Dae-Hyun Kim

Macroecologists and biogeographers continue to predict the distribution of species across space based on the relationship between biotic processes and environmental variables. This approach uses data related to, for example, species abundance or presence/absence, climate, geomorphology, and soils. Researchers have acknowledged in their statistical analyses the importance of accounting for the effects of spatial autocorrelation (SAC), which indicates a degree of dependence between pairs of nearby

Abstract Background Ecologists have achieved much progress in the study of mechanisms that maintain species coexistence and diversity. In this paper, we reviewed a wide range of past research related to these topics, focusing on five theoretical bodies: (1) coexistence by niche differentiation, (2) coexistence without niche differentiation, (3) coexistence along environmental stress gradients, (4) coexistence under non-equilibrium versus equilibrium conditions, and (5) modern perspectives. Resul

In coastal environments, biogeographic patterns are generally influenced by surface elevation and horizontal distance from sea water. However, it is still unclear whether these major topographic factors are significant controls of vegetation patterns across spatial scales at which different physical processes operate. This study investigated such a topography-vegetation relationship in a Danish salt marsh, focusing upon two scales: a macro-scale (ca. 500 m) across the marsh platform, encompassin

Biogeographers emphasize the presence of scale-dependence in vegetation–environment relationships. This research addresses the issue of scale-dependence, focusing on spatial correspondence of floristic and edaphic gradients across salt marsh creeks at Skallingen, Denmark. We employed a hierarchical approach, which compared vegetation and soil gradients at both fine and coarse scales. At the fine scale, we used ordination techniques to identify the gradient structure of vegetation and soil data a

Long-term variation of mean sea level has been considered the primary exogenous factor of vegetation dynamics in salt marshes. In this study, we address the importance of short-term, wind-induced rise of the sea surface in such biogeographic changes. There was an unusual opportunity for examining field data on plant species frequency, sea-level variation, and sedimentation acquired from the Skallingen salt marsh in Denmark since the 1930s. The environmental and floristic history of Skallingen wa

Several studies in the hydrology field have reported differences in outcomes between models in which spatial autocorrelation (SAC) is accounted for and those in which SAC is not. However, the capacity to predict the magnitude of such differences is still ambiguous. In this study, we hypothesized that SAC, inherently possessed by a response variable, influences spatial modeling outcomes. We selected ten watersheds in the USA and analyzed if water quality variables with higher Moran’s I values und

Coastal dunes display complex relationships among soil properties, vegetation, and geomorphology driven by marine and atmospheric dynamics. Considering topography as a fundamental control of the relations, this study investigated its influence on the spatial pattern of soil attributes in a coastal dune. We systematically collected 193 soil samples at intervals of 20 m from the Sindu coastal dunefield, South Korea, and analyzed 11 soil attributes. Principal component analysis extracted four main

Zonal patterns of salt marsh plants and physical conditions have been addressed primarily across the elevation gradient from inland to coastline rather than across tidal creeks in relation to their hydro-geomorphic processes such as bar formation and bank erosion. We found at a Danish marsh that by shaping major geomorphic features and providing sediments to the adjacent sites, fluvial-geomorphic processes of tidal creeks exert fundamental controls on the cross-channel distribution of abiotic an

The level of spatial autocorrelation (SAC) present in model residuals can have a detrimental influence on statistical inferences in geographical ecology. There has been significant progress in understanding the nature and causes of residual SAC and developing new methods to reduce the SAC. However, ecologists have not yet found a suitable answer as to when the level of residual autocorrelation is likely to magnify and whether its shift through spatial regression (i.e. the difference in the resid

Effects of spatial autocorrelation (SAC), or spatial structure, have often been neglected in the conventional models of pedogeomorphological processes. Based on soil, vegetation, and topographic data collected in a coastal dunefield in western Korea, this research developed three soil moisture–landscape models, each incorporating SAC at fine, broad, and multiple scales, respectively, into a non-spatial ordinary least squares (OLS) model. All of these spatially explicit models showed better perfo

This research investigated how the strength of vegetation-soil-topography couplings varied along a gradient of biogeomorphic succession in two distinct fluvial systems: a forested river floodplain and a coastal salt marsh creek. The strength of couplings was quantified as tri-variance, which was calculated by correlating three singular axes, one each extracted using three-block partial least squares from vegetation, soil, and topography data blocks. Within each system, tri-variance was examined