Chan-Ryul Park

A regional phenology model for detecting onset of greenness in temperate mixed forests, Korea: an application of MODIS leaf area index

Abstract A regional phenology model for detecting onset of vegetation greenness was developed using year 2001MODIS land products in temperate mixed forests in Korea. The model incorporates a digital elevation model (DEM), moderate resolution imaging spectroradiometer (MODIS) landcover and leaf area index (LAI) products, and climate data from weather-monitoring stations. MODIS-based onset of greenness varied spatially and showed significant correlation with air temperature (r=−0.70, p

Scale‐dependent effects of landscape composition and configuration on natural enemy diversity, crop herbivory, and yields

(1) Land-use intensification in agricultural landscapes has led to changes in the way habitats and resources are distributed in space. Pests and their natural enemies are influenced by these changes, and by the farming intensity of crop fields. However, it is unknown whether the composition of landscapes (amount and diversity of land cover types) or their configuration (spatial arrangement of cover types) are more important for natural enemy diversity, and how they impact crop damage and yields. In addition, effects of interactions between local farming practices (organic vs. conventional) and landscape variables are unclear. (2) Here, we make use of a data set where landscape composition and configuration were uncorrelated across multiple spatial scales. Natural enemies, crop damage, and yields were sampled in 35 organic and conventional crop fields. Out of seven broad natural enemy taxa, five were positively affected by a complex landscape configuration. In contrast, only carabids were positively affected by the amount of seminatural habitat around fields. Increasing diversity of land cover types had positive effects on some, but negative effects on other taxa. Effect sizes varied among taxa but increased with increasing spatial scale, defined by circular areas of increasing radius around fields. (3) The diversity of aerial, but not of ground-dwelling enemies was higher in fields under organic than conventional management. Interactions of local and landscape variables were important for birds, but not other enemies. Bird richness was higher in organic fields in simple landscapes, but not in landscapes with complex configuration or high land cover diversity. (4) Crop damage decreased with landscape diversity, but increased in conventional fields with complex configuration. Yields increased with both parameters in conventional fields only, and were higher on average in organic compared to conventional fields. Enemy diversity was positively related to crop damage, indicating positive density-dependence of enemies on pests. However, the diversity of aerial enemies was also positively related to yields. (5) Our results suggest that the effectiveness of agrienvironmental schemes for managing natural enemy diversity, crop damage and yields could be enhanced by optimizing the effects of distinct landscape parameters, particularly landscape configuration and diversity, across scales.

Bibosoop: A Unique Korean Biotope for Cavity Nesting Birds

In Korea, a bibosoop is a type of village grove fostered to complement a weak part of the village from a Feng-Shui perspective. We examined the characteristics of bird communities in remaining bibosoops in two regions, Gyeonggi-do Province and Jeollanam-do Province. We surveyed patch preferences of birds at two landscapes in Gyeonggi-do Province. One contains a bibosoop with other rural landscape elements, and the other does not have a bibosoop. The two landscapes of Gyeonggi-do Province were similar to each other in the distribution of landscape elements. We observed that species richness was significantly higher at the site with a bibosoop, and that tits, Mandarian ducks, starlings, Eurasian scops owls, and woodpeckers utilized the bibosoop as a nesting site. Birds preferred the landscape with the bibosoop, and the internal movement of birds was significantly higher at the landscape with the bibosoop than at the other. The results suggest that bibosoops serve as a unique biotope that provides nest sites for cavity nesters, especially near nest-insufficient forests, and enhance the internal movements of birds among patches in the landscape.

Prey distribution, foliage structure, and foraging behavior of insectivorous birds in two oak species (Quercus serrata and Q. variabilis)

We examined foraging behaviors of four insectivorous bird species (Great Tit Parus major, Varied Tit P. varius, Long-tailed Tit Aegithalos caudatus and Japanese White-eye Zosterops japonica) on the two oak species (Q. serrata and Q. variabilis) in relation to fine-scale foliage structures, abundance, and distribution of folivorous insects and physical and chemical characteristics of leaves. There was no difference in the mean number of insects for each oak species, but there was a significant difference in the mean biomass. The distance from twigs or branches to leaf tips or blade-petiole junctions showed that leaves of Q. variabilis were more dispersed than those of Q. serrata. The different size distribution of insects influenced insect sizes selected and foraging maneuvers used by each bird species. Parus major and P.varius fed on beetles (low energy gain) with perch-gleaning (the most energy-saving maneuver) from the upper side of leaves on Q. variabilis, whereas they fed on large lepidopteran larvae (high energy gain) from the lower side of leaves on Q. serrata using a variety of maneuvers (including energy-consuming ones). Both A. caudatus and Z. japonica fed on insects from the lower side of leaves by hang-gleaning and reach-gleaning, respectively. These species appeared to be morphologically adapted to the energy-consuming but more effective maneuvers used to take preys from the undersides of leaves. We hypothesize that differences in foliage structures between closely related species of trees have evolved as a balance between defense against folivorous insects and attraction of insectivorous birds.

Tree Species Preference and Inter-specific Difference of Foraging Maneuver, Trees and Location among Four Canopy-dwelling Birds at High-elevation Temperate Deciduous Forest in Mt. Jumbongsan

Abstract This study was conducted to reveal tree species preference and inter‐specific difference of foraging behavior among four canopy‐dwelling birds at forest dominated by Quercus mongolica, Acer pseudosieboldian and Carpinus cordata at 1,000 meters above sea level during breeding season of birds from 1995 to 1997 in Mt. Jumbongsan. Breeding birds were about 25 species and dominant birds were Erithacus cyane, Parus ater and Parus palustris. A relatively high number of bush‐nesters can be a characteristic of breeding bird community at study area. Three gleaners (Tits, P. varius, P. palustris and P. ater) selectively preferred the trees irrespective of dominant tree species, whereas bark foragers (Nuthatch, Sitta europaea) utilized the dominant trees. The four birds showed significant inter‐specific difference in use of foraging location, but the three tits did not show significant inter‐specific difference in use of foraging maneuver and trees. Closely related tits may coexist with each other by inter‐specific different use of foraging location determined by foliage structure and leaf arrangement.

Comparing Connectivity in Forest Networks of Seven Metropolitan Cities of South Korea

This quantitative research aims to examine the connectivity of forest networks in seven metropolitan cities of South Korea using a graph-theoretical approach. We first estimated an overall network connectivity at multi-scales (i.e., dispersal distances), ranging from 100 m to 20 km, and quantified the contribution of small forest patches (less than 10 ha) to the overall network connectivity by comparing networks according to the presence and absence of small ones. As a result, the cities were divided into two groups depending on the network connectivity; one group of cities with high connectivity such as Daegu, Daejeon, and Ulsan and the other group of cities with low connectivity including Gwangju, Busan, Seoul, and Incheon. The result showed that small forest patches, especially in the cities with low connectivity, played a key role as stepping stones that connect large forested patches, thereby contributing to maintaining connectivity. This study also suggests that large and well-connected forest areas may be the key factor to preserve the connectivity in the cities with high connectivity, while the cites with low connectivity are in need of some complementary strategies. Through the study, we suggest that the creation of new forest patches in the areas where a gap in connectivity presents is needed in order to improve connectivity; and that the conservation of the existing small forest patches is essential in order to maintain the current connectivity level.

Influence of tree thinning on the abundance of mammals in a Japanese larch Larix kaempferi plantation

ABSTRACT We examined the influence of tree thinning on the abundance of mammals in a Japanese larch Larix kaempferi plantation in Mt Gariwang, Pyeongchang, South Korea. In 2014 and 2015, from April to October, we recorded the presence of tracks as a proxy for abundance, for the following seven mammalian species: Korean hare Lepus coreanus, raccoon dog Nyctereutes procyonoides, Siberian weasel Mustela sibirica, Eurasian badger Meles meles, water deer Hydropotes inermis, roe deer Capreolus pygargus, and wild boar Sus scrofa. We also assessed how the intensity of tree thinning affected vegetation cover; there were significant differences in number of standing trees, basal area, coverage of vegetation layers, and number and volume of downed trees among the control, moderately thinned, and intensively thinned stands. We found significant differences in the abundance of tracks among the stands for three mammal species. In four mammal species, the abundance of track was significantly correlated with volume of downed trees, coverage of ground vegetation, number of downed trees, and number of standing trees, according to stepwise analysis. The presence and abundance of mammals is linked to habitat variables and forest managers should consider how habitat modifications will affect wildlife.

Characteristics of Bird Community in Mangyeong River Area

This study was conducted to clarify the characteristics of bird community and habitat types in Mangyeong River area from Aug. 1999 to Jun. 2000. Paddy field was the most dominant land use type. Water area, mudflat, shrub field, urban area and green house were also dominant land use types in study area. Eighty-eight bird species were recorded during study period. Maximum number of species and individuals were shown as 58 species and 7,084 individuals in Oct. and Jan., respectively. There were low number of diving ducks and clumped pattern of waterfowl distribution of bird community in Mangyeong River area. Dabbling ducks distributed at upper reaches near Samrye Bridge, and plovers and sandpipers at lower reaches near estuary. Those results suggest that creation of pools over one meter water-depth and restoration of paddy field into riparian zone with diverse shrubs are required to increase the bird diversity in the Mangyeong rived.

Characteristics of mammal abundance relative to habitat variables in temperate forests

This study was conducted to examine the characteristics of mammal abundance that are related to habitat variables in natural deciduous forest and Japanese larch (Larix leptolepis) plantation in the national forest of Mt. Gariwang, Pyeongchang, Korea. Habitat variables differed between forest types. We counted the mammal trails of Korean hares (Lepus coreanus), raccoon dogs (Nyctereutes procyonoides), Siberian weasels (Mustela sibirica), Eurasian badgers (Meles meles), water deer (Hydropotes inermis) and wild boars (Sus scrofa) during the study period. Eurasian badgers, water deer, and wild boars exhibited one or two significant correlations with coverage of understory, downed trees, and coverage of overstory, as determined using a stepwise approach. Habitat variables could be used as predictors of mammal abundance, and thus forest managers should consider such variables in mammal conservation and management activities.

Spatial Network Analysis of Pathogen Spread in Korean Rice Farming Areas Using Graph Theory

The spread and expansion of pests and pathogens due to climate change have caused considerable reduction of rice yield in agricultural landscapes. This study was conducted to quantitatively analyze the spread of rice pathogens carried by insect pests on spatial network in South Korea using graphtheoretic methods. We identified the connectivity “backbone” of pathogen spread network among the cities along the coastal area of West Sea. In addition, we graphically represented 1) the core areas that can cause local and regional outbreaks of pathogens; and 2) the areas that act as bottlenecks in the spread of pathogen which can link the core areas. Especially, the cities in the coastal areas of West Sea that have the high density of rice crops, represented a low spread resistance to pathogen infection. These results may suggest insights into planning the integrated pest management possibly through regional collaboration.