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Aquatic invertebrates are the major important fauna to sustain the paddy ecosystem as predators of the lower trophic level and prey for birds in food-web dynamics as well. The nationwide distribution of scavenger beetles (Hydrophilidae) that is the top predator in an aquatic insect in the paddy field was investigated. A total of 15 scavenger beetles were recognized. Enochrus simulans (98.6%) and Laccobius bedeli (87.7%) showed a high frequency of occurrence on a nationwide scale. The majority of scavenger beetles were higher frequency of occurrence in mountainous regions(33.7%) than in open field regions(5.0%). On the other hand, E. uniformis, Coelostoma stultum and Berosus japonicus showed a low occurrence frequency. Hydrochara affinis, Sternolophus rufipes, Amphiops mater, B. elongatulus, B. signaticollis punctipennis, B. lewisius and H. libera showed regional specific distribution aspect. Therefore, these species can be used as biological index to research the biotic changes in paddy ecology according to an agro-environmental changes including climatic change in the future.

Effects of Light Quality and Lighting Type Using an LED Chamber System on Chrysanthemum Growth and Development Cultured In Vitro Jeong Wook Heo, Yong Beom Lee, Yu Seob Chang, Jeong Taek Lee and Deog Bae Lee(Climate Change & Agroeconomy Division, Department of Agricultural Environment, National Academy of Agricultural Science, RDA, Suwon 441-100, Korea, Research Policy Bureau, On-Farm Research Division, Rural Development Administration, Suwon 441-100, Korea, Farming Automation Division, Department of Agricultural Engineering, National Academy of Agricultural Science, RDA, Suwon 441-100, Korea)

Laboratory trial on the control effect of Beauveria bassiana against Paratlanticus ussuriensis was carried out with fungi collected from South Korea, China and Peru. All B. bassiana species from collected at each site had a strong fungicidal activity against P. ussuriensis. The Abbott's formula was the highest showing 100% mortality and the others also showed over 60% mortality. It took 3 to 6 days until katydid attained to death after inoculation with all B. bassiana treatments. From this trial, B. bassiana fungus was found to have some effects as pathogenicity of entomopathogenic activity against P. ussuriensis. So B. bassiana could be considered as one of the environment-friendly and effective pesticides for the control of P. ussuriensis.

Characteristics of habitat alteration and post-embryonic development of Paratlanticus ussuriensis were investigated in the mountain region of Bitanri, Yeongdong county, Chungcheongbuk-do from 2007 to 2009. Overwintered eggs under the ground in the hillside were hatched from late March to early April. The soil temperature during this season was . Young nymphs lived mainly at the hillside by eating oak tree leaves but the 3rd or 4th instars switched their habitat to orchards near the hillside in early May, which is the time for sprouting of peach leaves. Old nymphs developed into the adult stage at the orchards in late May and moved back to the hillside in late June. Duration of post-embryonic development from the first instar nymph to adult was 49.2 days after 7 moltings at . Female adults collected from the field had long ovipositor (26.2 mm) and were slightly longer in the body length, hind femur, tegmen and pronotum than those of males.

This study was conducted to determine the phototactic response of Paratlanticus ussuriensis to different wavelength of light by the use of LEDs and to provide a basic information for developing an improved trap with the longer trapping efficiency to control environment-friendly this katydid. P. ussuriensis were attracted to the single LED light source, especially, blue and white. For the multiple LED light sources, the movement of P. ussuriensis was not significantly different among LED-light bands. Overall, P. ussuriensis had a tendency to move to light source although they were not attracted to a specific wavelength of light. These methods may be used as information for conducting a phototactic response of other insects.

In 2006 and 2007, there was a big outbreak of the Ussur Brown Katydid, Paratlanticus ussurriensis in the central part of Korea attacking some orchard trees. Until 2000, the katydid had not been regarded as an agricultural pest because they were distributed widely in Korea with low population density and their habitats were confined mainly to hillsides of forested areas. The fact that katydid attacked orchard trees with a higher population density seemed to be related to a change in feeding environment. And the shift of their habitats from oak woodlands to commercial orchards was thought to be related to the nutritional contents of their feed. In an attempt to understand these relationships, we conducted an ecological study of the affected areas. When the katydids changed their habitats in early May of 2008 and 2009, they shifted their host plants from oak trees to peach trees. The habitat shift was closely related to the nitrogen (N) content of the host plant leaves. When katydid moved to the hillside adjacent to orchard farm, N content of oak tree leaves decreased dramatically from 5.3% to 2.2%. At that time N content of peach tree leaves were higher than the 2.2% of oak leaves, showing 3.5~5.0%. This range of N content of peach tree leaves has been consistent until late June. And feed preference analysis carried out in the laboratory showed that katydid prefered peach tree leaves to peach fruit to oak tree leaves.

The effect of earthworm and dung beetle on cattle dung pat decomposition was assessed by combining quantification of earthworm density and with or without dung beetle in pats and measurements of the decomposition rate of these pats. Cattle dung decomposition rate was higher in the pots treated with both earthworm and dung beetle than in the pots with either earthworm or beetle alone. After dung beetle and earthworm activity, the growth of oat in earthworm with dung beetle treatment was similar effect with fertilizer treatment. Dung beetle was responsible for dung decomposition until 78% moisture content in the dung, earthworm was responsible for up to 30% moisture of dung, and two group were not shown any activity for decomposition less 30% moisture content of dung. Therefore dung in the different periods could be broken down by each group. The disappearance and conveyance of dung by earthworm and dung beetle was 72% of the initial dung amount. 10.2% of 72% dung was used making brood balls by dung beetle. Earthworm activity was not an impediment on making brood balls by dung beetles. The interaction of earthworm and dung beetle may have a complementary cooperation rather than competition in the same dung pat. Indeed, development of earthworm accelerate to coexist with dung beetles instead without dung beetles. From this result, maximum benefits of the effective earthworm and dung beetle can be achieved, it is needed to preserve population of earthworm and dung beetles in pasture to sustainable agricultural environment.

Temperature effects on diapause termination of Paratlanticus ussuriensis eggs were studied by measuring embryonic development and hatching rates at various conditions of indoor chilling and overwintering temperatures. Diapausing eggs of P. ussuriensis did not hatch at continued incubation at and even after chilling for once at either or for 30, 45 and 60 days. In addition, double chillings at with a 90 days interval at did not induce hatching of diapausing eggs. However, double chillings at induced hatching at 3.626.7%. When eggs were incubated at after chilling for once at for various periods, those weights were not changed but those chilled at gradually increased to approximately 1.5 times. When 60-days-old eggs were artificially deposited under the soil at three different mountain sites in September 2007, the hatching rates of the first-overwintered eggs were 11.3, 3.5 and 4.1% and those of the second-overwintered eggs were 25.1, 21.6 and 0.4% at Hoepori, Bitanri and Hwasanri, respectively. Most eggs were hatched from mid-March to mid-April but little bit earlier in southern regions. During the hatching period soil temperatures in three tested locations were around 8 to . In overall, diapausing eggs of P. ussuriensis were greatly influenced by chilling temperature conditions and those repeated cycles, and may required overwintering for one or two times to hatch for the post-embryonic development.

The aim of this study was to investigate whether differences in the distribution of soil invertebrates among different vegetation types (forest, reservoir, and crop land types) in rural area. A total of 18 orders and 137 species were collected by pitfall traps. Species numbers were the lowest (33 species) at the Chamaecyparis obtusa plantation (St. 6). On the forest sites, the individual number of Hymenoptera was the most abundant, and Acari and Coleoptera was the relatively more abundant than the other sites. On the reservoir sites (Salix chaenomeloides community), the individual number of Collembola was the most abundant, and Diptera was the relatively more abundant than the other sites. On the crop land sites, the individual numbers of Collembola, Hymenoptera, and Araneae were the relatively more abundant than the other orders. The density of Araneae was higher in the reservoir and crop land sites than in the forest sites. From a point of view of biodiversity, although the diversity index(H') was the highest in the mixed broad-leaved forest type (St. 2) with Quercus serrata and Q. acutissima, and the lowest in the upland levee of crop land(St. 11), there was no significant difference among the habitat or vegetation types. According to the community analysis, the soil invertebrates could be divided into 4 groups, the mixed broad-leaved forest type (A group), the plantation or pure forest type (B group), the reservoir type (C group), and the crop land type (D group).

This study was aimed at assess environmental conservation functions by analyzing the change of land use areas in agricultural fields between 1999 and 2006, and comparing land surface temperature distribution between 1994 and 2006 in Yongin city. Land use maps of Yongin city were obtained from soil maps for 1999, Quickbird satellite images(less than 1 m) and parcel map for 2006. The land use area for Yongin city was in the order of forest > paddy field > upland > residence & building in 1999, and forest > residence & building > paddy field > upland in 2006. Decrease of paddy and upland fields reduced 34% and 41% of the capability of agricultural multifunctionality as to environment including flood control, groundwater recharge, and air cooling. Land surface temperature(LST) was derived from Landsat TM thermal infrared band acquired in September of 1994 and 2006 and classified into three grades. The results impplied that green vegetation in agricultural field and forest play an important role to reduce land surface temperature in warm season.

Winter migratory birds gather in paddy rice fields to feed shed rice grains. The Korean Ministry of Environment has practiced a policy program Contract on Paddy Field Management (CPFM) during winter fallow since 2002. This program starts with a contract between local governments and farmers, and the government pays a differential subsidy to farmers who finish spreading rice straw, cultivating barley, letting the whole rice plant without harvest, and submerging paddy fields for winter migratory birds. As more local governments have operated CPFM program, the total area on the contract and subsidy budget has increased yearly since 2002. This program could have its stable position as a successful policy by giving profits to farmers. With the program extended, the population of winter migratory birds has been greatly. For the evaluation of environmental performance of a policy, we analyzed this CPFM program by introducing some indicators in the form of Driving Force-State-Response Framework. The indicators were composed of 3 categorized indicators; the area of paddy land contracted under this program as 'driving force' indicator, population of birds, the number of bird species and the amount of feces as 'state' indicators, and the size of monetary support, the number of farmers or local governments participating, and public perception as 'response' indicators. The contract area of paddy field under CPFM could be a good biodiversity indicator reflecting potential performance of this policy measure in the light of its linkage to the population of winter migratory birds. And the share of CPFM land of the whole agricultural land might also be used as a useful indicator of policy evaluation for improvement of wildlife diversity. The 'state' indicators such as population of birds and the number of bird species could be matched to 'driving force' indicator, but the total CPFM area of each site could not reflect the effect of areas under different management practices. However, the amount of bird feces could reflect differences in environmental performance with management practices as 'state' indicators. The development of indicators indicating 'response' such as farmers' behavior, public perception, and policy makers' willingness is also needed to support a successful implementation and improvement of this policy measure with the development of 'performance' indicators integrating all these indicators.

The increase in average air temperature over the past 100 years in northern Asia including Korea is the greatest (about ) among the various regions of the world. Considering a further warming projected by the IPCC, fluctuations of agro-climatic indices under climate change must precede an evaluation of vulnerability. The purpose of this study is to analyze how climate changes represented by global warming have altered agro-climatic indices in Korea over various time scales. Drought index during the rice-transplanting period of 15 May to 5 June has changed toward the favorable with recently increased precipitation in the Taebaek Alpine and Semi-Alpine Zone, and Yeongnam Basin and Inland Zone. The frequency of low temperature occurrence below during the rice transplanting has decreased, while climatic production index (CPI) has fallen because of the decreased sunshine hour and increased temperature during the rice ripening period. We therefore concluded that the recent change of climate conditions was against the rice productivity in Korea.

This study was carried out to investigate yearly change in the precipitation component and the source strength to acid precipitation at Iksan area from 1997 to 2003. The average ratio of acid precipitation was 70.0% in 1997, 56.3% in 1998 and 36.4% in 2003. On the other hand, it ranged from 6.9 to 19.2% when precipitation was less from 1999 to 2002. The average annual wet depositions of major ionic component in precipitation were calculated by multiplying equivalent concentration by precipitation. The order of major anion component in precipitation was ${SO_4}^{2-}>Cl^->{NO_3}^-$. On the other hand, the concentration of cation component were ${Ca_2}^+>Na^+>{NH_4}^+>{Mg_2}^+>K^+$ in order. The negative correlation was shown between pH and ionic component in precipitation except for . The correlation coefficient between pH and was highly significant as -0.508, which suggests that played important role in increasing the acidity of precipitation. Also the anions such as were highly significant with cations such as . As a result though pH was enable to use the acidity index of precipitation in somewhere, evaluating only pH in precipitation was insufficient as the index to establish corresponding strategy for acid rain.

This study was conducted to evaluate the influence of pollutant loads on the water quality in the Mankyeong River from January 2002 to December 2004. The BOD level in upstream ranged from 0.58 to 1.57 mg , which would be in I grade according to water quality criteria by Ministry of Environment but BOD level in midstream and downstream was III grade. T-N contents were high in midstream and the average T-P level ranged from 0.06 to 2.70 mg . The point raw loads of BOD was high in Iksancheon, Mokcheonpo and Cheongha basin. The point raw loads of T-N and T-P were high in Iksancheon and Cheongha watershed. The non-point low loads of BOD were 3,931 kg , 2,870 kg and 2,827 kg in Mokcheonpo, Top and Jeonju watershed, respectively. The major source of BOD effluent load was population, that of T-N and T-P effluent loads was livestock. The delivered load of T-N were high in Jeonju, Mokcheonpo, Gosan, Iksancheon watershed in order. The delivered load of T-N was high in Jeonju watershed and that of T-P was high in Jeonju and Iksancheon watershed. The delivery ratio of BOD and T-N at dry season were below 100% except Mokcheonpo watershed. The delivery ratio of BOD and T-N at raining season were high in Gosan watershed.

This study was peformed to assess environmental effect through rice culture with sewage irrigation using Iksan stream water from 2002 to 2003. Contents of in irrigation water keep up one day at the tillering stage and panicle formation stage were decreased 40% and 52% respectively, but that of continued 4 days was decreased . The in run off by reduction 50% fertilization were more decreased 17% and 44% respectively, than those of conventional fertilization level. Amount of K and loss in infiltration water were more decreased 18% and 4% respectively, those of than conventional fertilization level. The Cu and Pb contents in soil of after experiment were slightly increased but other heavy metals were not accumulated. The rice yield by reduction 50% fertilization level was not significant compare with conventional fertilization level but head rice rate was increased.

This study was conducted to evaluate the influence of pollutant loads on the water quality in the Dongjin River area from January 2003 to December 2004. The average value of BOD and T-N showed the highest peak in Yongho, Dukcheon watershed among Dongjin River. Concentrations of BOD, T-N and T-P in Jeongeup watershed were 2.29 mg , 4.40 mg and 0.27 mg , respectively. Concentration of BOD in Chilbo was 1.19 mg which would be in the grade I according to water quality criteria by Ministry of Environment. The BOD level in Wonpeung and Sinpeung watershed ranged from 4.06 to 7.35 mg . The T-N effluent loads of non-point pollutants were high in Wonpeung, Gobu, Yongho Dukcheon, Jeongeup and Sinpeung watershed in order. The major sources of BOD, T-N and T-P effluent loads were Livestock. The T-P effluent load of non-point pollutant was 68 kg in Wonpeung, 58 kg in Yongho Dukcheon and 45 kg Jeongeup watershed. The delivered loads of BOD was high in Gobucheon, while both T-N and T-P were high in Yongho Dukcheon. The delivery ratio of BOD and T-N at dry season was below 100% in all watershed of Dongjin River. The delivery ratio of T-N at raining season was high in Yongho Dukcheon and Chilbo watershed

The influence of pollutant loads on the water quality in Jeongeupcheon of Dongjin river was evaluated from Jan. 2002 to Dec. 2003 for two years. The range of pH in water was . The EC level in upstream ranged from 83 to with the highest value in autumn. The BOD level in upstream rang ed from 0.61 to 1.27 mg/L, which would be I grade according to water quality criteria by Ministry of Environment, but that in downstream was III grade. The average T-N level in midstream ranged from 6.10 to 10.84 mg/L which was the highest values throughout the stretch of the river. The average T-P levels ranged from. 0.41 to 0.98 mg/L Jeongeupcheon was suitable for the agricultural usage based upon one year analysis of river water quality. The effluent loads of BOD was high in midstream (J4) with 553 kg/day. The major sources of T-N loads were livestock, population, land use, and industry in order. The effluent loads of T-N was high in J4 by population and industry while that of T-N was high in J5 and J6 by livestock and land use. The delivered loads of T-N was high in downstream The delivered loads of T-P was low as compared with those of BOD and T-N. The delivery ratio of T-N ranged from 6 to 38%.

This study was conducted to get some vegetation information and to find out a way to conseue the ecosystem in the Dongjin River. The riparian vegetation was investigated by Zurich-Montpellier school`s method from June 2001 to March 2002. The number of riparian plants were 73 families, 188 genera, 238 species, 33 varieties or 272 Taxa in Dongjin River. The characteristics of life farm spectra were 97 therophytes (35.7%), 78 hydrophytes (28.7%), 41 hemicryptophytes (15.1%) 22 geophytes (8.1%), and 12 chamaephytes (4.4%). The riparian vegetation was identified 8 plant communities (Potamogeton brechtoldii, Hydrilla verticillata, Ceratophyllum demersum, Potamogeton malaianus, Phragmites japonica, Persicaria thunbergii, Cardamine scutata, Persicaria hydropiper) in upstream, 4 plant communities (Zizania latifoliar, Phragmites communis, Persicaria thunbergii, Humulus japonicus) in midstream and 8 plant communities (Hydrocharis dubia, Ceratophyllum demersum, Trapa japonica, Zizania latifolia, Paspalum distichum, Phragmites communis, Pericaria thunbergii, Amphicarpaea edgeworthii) in downstream of the Dongjin River.

This study was conducted to get some information on plants abilities to enhance water purification and to find out away to conserve the ecosystem in Mankyeong river. Vegetation were surveyed at 4 sites pointing by 1:5,000 topographical map, from June 2001 through March 2002. T-N content in water were high in all sites of Mankyeong river, the average T-N levels were 8.59 and 17.23 mg/L, summer and winter, respectively. The average T-P level during summer was 0.47 mg/L but that was 1.79 mg/L during winter. The BOD level in Mankyeong upstream ranged from 0.95 to 2.57 mg/L which would be in I or II grade according to water quality criteria by Ministry of Environment but BOD level in Mankyeong downstream ranged from 6.87 to 9.72 mg/L. The plant species of river flora were found 251, 98 and 85, upstream midstream and down stream, respectively. Among the surveyed plants, Ceratophyllum demersum, submerged plant and Nuphar subinteperrimum took up higher contents of phosphate and nitrogen than other piano. The Phragmites communis and Zizania latifolia having much biomass were thought to be suitable plants for enhancement of e natural water purification.

Concentrations of DDT and its metabolites (DDTs), HCH isomers (HCHs: hexachlorocyclohex‐anes), chlordane compounds (CHLs), HCB (hexachlorobenzene) were determined in agricultural soils, dumpsite soils, and riverine sediments collected from Manila and its nearby provinces in the Philippines. Relatively low DDT and HCH residue levels were detected in agricultural soil samples examined. These findings reflect the decline in the usage of organochlorine chemicals for agricultural purposes in the Philippines. In the case of the dumpsite soils collected from Smokey Mountain, significant DDT, HCB, and HCH residue levels were detected, which may be attributed to the extensive use of organochlorine chemicals for public health purposes. While marked levels of PCB residues could be due to the PCB‐contaminated industrial wastes dumped in the area. Significant levels of CHLs and DDTs were also observed in Pasig river sediments coming from industrial sources, as the river is used as an internal artery for the transport ...

Salinity induced inhibition in germination and early stages of cabbage (Brassica oleracea capitata L.) [two varieties (autumn cabbage and spring cabbage)] were measured in response to increasing NaCl concentration. The salinity (NaCl) concentrations in solution were 0 (control), 4.7, 9.4 and 14.1 dS m(-1). Different concentrations of salt stress had considerable effect on germination, germination rate (1/t50, where t50 is the time to 50% of germination), root and shoot lengths, root, shoot and plant fresh weight of cabbage. Final germination in cabbage (autumn cabbage and spring cabbage) showed significant inhibition with increasing salt stress up to 14.1 dS m(-1) NaCl. The required time for germination increased with increasing concentration of salt. The seedling growth was strongly inhibited by all salt levels, particularly at 14.1 dS m(-1). Furthermore Root growth was more affected then shoots growth by salt stress. Fresh weights of root, shoot and plant were also severely affected by different salinity treatments. Linear regression revealed a significant negative relationship between salinity and final germination, germination rate, root and shoot lengths and fresh weights of roots, shoots and plants.