• Korean Journal of Agricultural Science
• /
• v.10 no.1
• /
• pp.61-73
• /
• 1983

This study was conducted to obtain fundamental informations on the improvement of cropping system to increase in land utilization rate and crop production. In order to group the characteristics of areas, Chungnam province was classified into 4 classes: Suburb (Daedeog Gun, Cheonwon Gun), Plain (Nonsan Gun, Dangjin Gun) Coastal (Seosan Gun, Boryeong Gun) and Hilly region (Gongju Gun, Cheongyang Gun). 100 farm households were sampled from each region, and cropping system and utilization state of paddy and upland in 1982 were surveyed. The results obtained were summarized as follows: 1. Average utilization rate of upland was 161.9 % The utilization rate of upland at plain was highest (188.9 %), and that at suburb showed lowest value (152.0%). 2. Number of crops cultivated at upland was 32 kinds. Among the rate of planting area of each crop. soybean showed highest rate of 18.8%, barley 15.4%, red-pepper 13.1% and chinese' cabbage 10.1% respectively, but the red pepper showed highest rate of planting area at suburb, the barley at hilly region and the soybean at plain and coastal region. 3. Average utilization rate of paddy was 115.6% and the utilization rate of paddy at suburb showed the highest value (140.0%) and that at coastal region the lowest value (108.2%). 4. 12 kinds of crops were cultivated at paddy before or after rice cultivation. Among the crops cultivated at paddy before or after rice cultivation, barley showed the highest area rate (5.0%) of cultivation and strawberry the next but the strawberry showed the highest area rate of cultivation at suburb and barley at other regions. 5. The cropping systems at upland were divided into single cropping and double cropping. Types of double cropping at upland were classified into 38 types by the combinations of crops. Among the types of double cropping, the rate of cultivation area of soybean after barley combination was 35.0%, but at suburb the rate of this type of cropping system was low and the double cropping of vegetable combinations showed high rate. 6. Types of double cropping at paddy were classified into 6 types. As a whole, double cropping of barley after rice combination showed highest rate of cultivation area (42.8%) among crop combinations but at suburb, the area rate of this type cropping was low and cultivation of fruit vegetable after rice showed highest rate. The area rate of post - cropping to rice was 76.3% of whole double cropping area at paddy and significantly higher than the rate of precropping to rice. 7. Some kinds of crop combinations were consisted of same family or closely related crops and the characteristics of the crop rotation between those crops are almost same. The area cultivated those unreasonable crop combinations were 19.09 ha. 8. At upland, planting area of the cereal crops, vegetale crops and industrial crops crops and industrial crops was 88.92ha, 93.70ha and 21.80ha respectively. The Planting area of cereal crops was significantly less than that of vegetable crops. 9. Most of all the research reports on the cropping system from 1910 to 1980 were about the post cropping after rice harvest. The objectives of researches could be classified into 14 kinds and the important objectives of researches were the planting time, the amounting of manuring, the quantity of seeding, the transplanting time, the ridging method, the sowing method and the variety test.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.46 no.6
• /
• pp.459-463
• /
• 2001

Changes of rice yield and soil physicochemical properties of the dry-seeded rice-barley double cropping system were investigated for 10 years from 1990 to 1999. Generally, seedling stand was more unstable in the rice-barley cropping system regardless of barley straw addition or removal than in the rice single cultivation as indicated by higher standard deviation of seedling stand across year. Rice yield in rice-barley double cropping cultivation was increased due to barley straw application starting from the second year, recording 2 to 19％ increase (average of 9％ for 10 years) due to higher spikelet number. Protein content and Mg/K equivalent ratio were similiar among the barley straw applied field, rice single crop and barley straw removed plots. Also, amylose content was not significantly different among cropping patterns. Physicochemical properties of soil was improved by applying the barley straw; soil porosity was higher and content of organic matter and cation exchange capacity of Ca increased but those of Mg and K did not differ.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.64 no.3
• /
• pp.234-245
• /
• 2019

In order to select the best varieties and cultivation methods for the production of domestic wheat for Hodugwaja(a walnut shaped confection), we carried out a 3-year experiment (2015~2017) to investigate the effect of different factors (crop variety, planting date, nitrogen fertilization) in a double cropping system (wheat then rice) on crop yields in the Cheonan area. Rice is the second crop in the system, and requires an accumulated temperature for 40 days of about $840{\sim}930^{\circ}C$ to ensure ripening. Transplanting dates for rice between June 29 and July 6 were suitable; transplanting on or after July 13 does not ensure ripening. The daily hours of sunshine ranged from 6.3 to 6.5 hours, which were slightly higher than the optimum of 6.0 to 6.1 hours. The higher the nitrogen fertilizer treatment, the higher culm length, and spike length of wheat. The yield of wheat per 10a tended to increase as the amount of nitrogen fertilizer increased. Wheat yields were highest for the Sooan variety, followed by Goso, followed by Keumgang. The number of days from transplanting to heading of rice were shortest for the Jopyeong variety followed by Unkwang, followed by Haedam. The yield of milled rice per 10a increased as the transplanting date was earlier and the transplanting date of June 9 showed the average yield of more than 500 kg in three varieties. From the results of the experiment, we recommend the Goso wheat variety and the Haedam rice variety for growing in a double cropping system under the climatic conditions of the Cheonan area.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.64 no.4
• /
• pp.459-468
• /
• 2019

Changes in growing periods and productivities of crops under double cropping of potato-rice, potato-soybean and potato-maize, were investigated at the Paddy Experimental Fields in Miryang City from 2015 to 2018. Spring potatoes planted in early March showed a yield of 2.1-2.3 ton/10a and a period of 90 days. In double cropping, growing period of rice, soybean, and maize was about 130, 125 and 115 days, respectively. The potato yield obtained was as much as 616, 330 and 815 kg/10a under double cropping with rice, soybean and maize, respectively. It is beneficial to sow the spring potatoes as early as possible to increase the yield and to secure the growing period of sequential crops. The introduction of summer medium-late variety grain crops into double cropping of spring potato and rice as well as into double cropping of spring potato and soybean/maize, was possible because of no sowing in the fall and plants were able to reach the heading growth stage before the safe heading limit of rice in particular. In the case of maize, the growth period was different according to the change in temperature over the year. The introduction of upland crops such as soybeans and maize instead of rice improved soil physicochemical properties in a short period of time, contributing to the increase of spring potato yields, but there was also a risk of damage by successive cropping for more than three years. Spring potato-maize showed higher yield in terms of starch production, and spring potato-soybean was found to be advantageous for net income.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.17 no.2
• /
• pp.173-181
• /
• 2015

Fluxes of carbon dioxide ($CO_2$) were measured above crop canopy using the Eddy Covariance (EC) method, and emission rate of methane ($CH_4$) was measured using Automatic Open/Close Chamber (AOCC) method during the 2012-2013 barley and rice growing season in a barley-rice double cropping field of Gimje, Korea. The net ecosystem exchange (NEE) of $CO_2$ in the paddy field was analyzed to be affected by crop growth (biomass, LAI, etc.) and environment (air temperature, solar radiation, etc.) factors. On the other hand, the emission rate of $CH_4$ was estimated to be affected by water management (soil condition). NEE of $CO_2$ in barley, rice and fallow period was -100.2, -374.1 and $+41.2g\;C\;m^{-2}$, respectively, and $CH_4$ emission in barley and rice period was 0.2 and $17.3g\;C\;m^{-2}$, respectively. When considering only $CO_2$, the barley-rice double cropping ecosystem was estimated as a carbon sink ($-433.0g\;C\;m^{-2}$). However, after considering the harvested crop biomass ($+600.3g\;C\;m^{-2}$) and $CH_4$ emission ($+17.5g\;C\;m^{-2}$), it turned into a carbon source ($+184.7g\;C\;m^{-2}$).

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.310-310
• /
• 2017

'Gawaji 1', an early maturing and low amylose content rice variety adaptable to double cropping system with barley as later winter crop., was developed by the crop breeding team of Crop Research Division, GARES, Hwaseong, Korea in 2016. 'Gawaji 1' was derived from a cross between 'Baegjinju' and 'Sangmibyeo' in 2004. This variety had heading date of August 4 in Gyeonggi Province. It had a semi-elect plant type and resistance to lodging with strong culm. Its culm length was 67 cm. This variety had 15 tillers per hill and 104 spikelets per panicle. It was medium grain variety showing 1,000 grain weight of brown rice of 19.3g. Its protein contents of milled rice was 8.2% which was lower than 'Baegjinju'. Its milling ratio was 75.5% which was higher than 'Baegjinju'. The yield of milled rice was 5.0 MT/ha under the ordinary culture of the local adaptability test in 3 areas of Gyeonggi Province for three years. 'Gawaji1' is highly adaptable to Gyeonggi Province, especially to northern region of Han River.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.345-345
• /
• 2017

In order to reduce rice cultivation area in paddy fields and to increase domestic self-sufficiency of imported upland grain, it is necessary to increase double cropping area of upland crops in paddy field in accordance with decrease of rice consumption in Korea. The double cropping of spring potato-summer grain maize can be combined because of enough growing season in the southern plain of Korea. Spring potato, which is profitable, can be planted in the late February and harvested in the late May as the main crop. Subsequent grain maize can be planted in early June and harvested in November (maturity in the early October). Spring potato (variety Soomi) yielded $2,544kg\;10a^{-1}$ (tuber) when planted in late February, 2016. When maize was planted in June as the second cropping crop, though growth of plant decreased much, grain yield decreased slightly compared to normal planting in April or May. There was enough time to dry maize ear in the field after maturity before harvesting, which saved labor and time for grain drying, since there is no autumn planting at the double cropping of spring potato-summer grain maize. When grain maize (variety Gwangpyeongok) was planted in the early June (June $10^{th}$), average grain yield of above $860kg\;10a^{-1}$ over 2 years of 2015 and 2016 was obtained, and the annual total yield (potato tuber + maize grain) of 3,400 kg $10a^{-1}$ was obtained. The result indicates that the double cropping of spring potato-summer maize using paddy fields in southern plain of Korea, could contribute to the self-sufficiency of upland crops through the maximum production.

• Korean Journal of Weed Science
• /
• v.5 no.2
• /
• pp.137-142
• /
• 1985

This experiment was conducted to know the difference in weed population in the five cropping patterns kept same for six years from 1976 such as ricebarley, potato-rice, pea-rice, rice-rye, and rice-fallow. More and many weeds were growing in single cropping field than double cropping field. Dominant weed species in pea-rice and potato-rice cropping patterns were M. vaginalis and S. hotarui, M. vaginalis and P. distinctus. Coefficient of similarity of the cropping patterns between pea-rice and potato-rice appeared higher than single cropping system. However, pea-rice and rice-fallow cropping patterns showed low coefficient of similarity.

• Korean Journal of Soil Science and Fertilizer
• /
• v.49 no.1
• /
• pp.7-11
• /
• 2016

Winter crops have been recognized as an alternative to soil management for fertility and crop productivity in paddy soil. Recently, rape has been produced at winter season and there is little research results on reduction of N fertilizer by adding rape residues for rice cultivation. In this study, we investigated the productivity and quality of rice by applying with 0, 27, 63, $90kg\;ha^{-1}$ of N fertilizer after input of rape residues into soil for two years. The highest yield of rice was average $4.68Mg\;ha^{-1}$ at the treatment applied with the $90kg\;N\;ha^{-1}$ with rape residue. It was reduced to N rate from 31.6 to $43.2kg\;N\;ha^{-1}$ in comparison to $4.53Mg\;ha^{-1}$ of maximum yield in treatment added $90kg\;N\;ha^{-1}$ with rape. Amylose content in rice was similar among treatments with/without rape residue, but protein content was lower in treatment with rape residue than in those without rape residue. In conclusion, input of rape residue in rice cultivation could be alternative to reduction of N fertilization and improvement of quality by adjusting rice productivity in paddy soil under cropping system.

• Journal of the Korean association of regional geographers
• /
• v.2 no.2
• /
• pp.1-8
• /
• 1996

The purpose of this study is to analyse the regional variation of tenancy system in later Yi-Dynasty in Korea. Materials for the analysis are acquired through materials(韓國土地農産調査報告), published in 1905 and agricultural census published in 1912. For the identification of difference of tenancy system between agricultural region, regionalization are conducted through by crop combination. Crop combination structure, using rank of LQ index, was clustered into five generic lesions through cluster analysis. In these contexts, this study has come to following conclusions. There are three types of tenancy system in materials; (1) Doji(賭地) system of which landrent was 1/3 agricultural products. Tenant healed the land tax and seeds. (2) Byoengjak(竝作) system of which landrent was 1/2 agricultural products. Landlords healed the land tax and seeds (3) Jeongaek(定額法) system of which landrent was fixed without relation to annual products. But through the analysis of relationship between agricultural region and tenancy system, a new tenancy system could be identified : Byeongjak(竝作) II system. In this system, landrent was 1/2 of agricultural products, but landlord and tenant shared the landtax and seed in common. In the distribution of these systems, relationship between tenancy system and agricultural regions could be identified. Doji system was distributed in the regions where rice and double cropping was specialized. But Byoeongjak(竝作) system was distributed in the regions where upland crops are specialized and ratio of Paddy field is comparatively low. Especially new types were emenged where ratio of paddy field was very low. These show that increase of productivity of land didn't induce the development of the right of ownership in land. The development of ownership was emerged only on the rice paddy fields. Barley cultivated through double-cropping passed into tenant's possessions. So nominal landrent in paddy field seemed to be raised, but actual landrent was maintained about 1/3 of Products through double cropping. On the contrary, rights of cultivation is developed through double cropping. As double cropping is developed, competition on paddy field between tenants was intensified. Consequently nominal land rent of Paddy fields should be raised.