• Korean Journal of Agricultural and Forest Meteorology
• /
• v.17 no.2
• /
• pp.144-155
• /
• 2015

Since the relocation project of equipment in 2011, the overall circumstances of KMA's agrometeorological observation have been significantly improved. Some concerns, however, emerged as a result of the evaluation of observational circumstances in terms of quality assurance after the field surveys on all stations. In order to improve the situation, we suggest: (1) establishment of clear management responsibilities, (2) enhancement of mutual cooperation system between relevant organizations, (3) detailed records of the changes in the observational circumstances, (4) standardization of equipment and sensors, (5) installation of unified information boards, (6) transfer of inappropriate facilities to an adjacent cropland and (7) setup of automated evaporation pan. In order to effectively utilize the high-quality data obtained through improvement of observational circumstances and an elaborate quality control, it is recommended to publish and disseminate regular reports on agrometeorological observations. To produce such a report on a trial basis, we have investigated different types of regular reports issued by domestic and foreign organizations, publication periods, geographical scope, main contents and amount. Based on our current situation, it would be beneficial to learn from the cases of Germany and Canada, which summarize mainly the distinctive agrometeorological phenomena occurred over the past years across the country.

• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.4
• /
• pp.556-567
• /
• 2020

Objective: To improve the utility of native grass resources as feed in China, we investigated the dynamics of protein and carbohydrate fractions among Inner Mongolian native grasses, during ensiling and the aerobic stage, using the Cornell Net Carbohydrate and Protein System. Methods: Silages were prepared without or with lactic acid bacteria (LAB) inoculant. We analyzed the protein and carbohydrate fractions and fermentation quality of silages at 0, 5, 15, 20, 30, and 60 d of ensiling, and the stability at 0.5, 2, 5, and 10 d during the aerobic stage. Results: Inner Mongolian native grass contained 10.8% crude protein (CP) and 3.6% water-soluble carbohydrates (WSC) on a dry matter basis. During ensiling, pH and CP and WSC content decreased (p<0.05), whereas lactic acid and ammonia nitrogen (N) content increased (p<0.05). Non-protein N (PA) content increased significantly, whereas rapidly degraded true protein (PB₁), intermediately degraded true protein (PB₂), total carbohydrate (CHO), sugars (CA), starch (CB₁), and degradable cell wall carbohydrate (CB₂) content decreased during ensiling (p<0.05). At 30 d of ensiling, control and LAB-treated silages were well preserved and had lower pH (<4.2) and ammonia-N content (<0.4 g/kg of fresh matter [FM]) and higher lactic acid content (>1.0% of FM). During the aerobic stage, CP, extract ether, WSC, lactic acid, acetic acid, PB₁, PB₂, true protein degraded slowly (PB₃), CHO, CA, CB₁, and CB₂ content decreased significantly in all silages, whereas pH, ammonia-N, PA, and bound true protein (PC) content increased significantly. Conclusion: Control and LAB-treated silages produced similar results in terms of fermentation quality, aerobic stability, and protein and carbohydrate fractions. Inner Mongolian native grass produced good silage, nutrients were preserved during ensiling and protein and carbohydrate losses largely occurred during the aerobic stage.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.15 no.4
• /
• pp.304-311
• /
• 2013

There have been increasing cases for farmers to install automated weather stations (AWS) at their farms and orchards in order to take countermeasures to more frequent weather disasters caused by climate variability and weather extremes. Although raw data are the same, the additive values as agrometeorological information may vary depending on data processing methods. User demands on appropriate information could also be different among crop species, cropping systems and even cultivars. We designed an internet based AWS data processing and display system to help diverse users (e.g., farmers), extension workers to access their weather data on specific demands. The system was implemented at a rural catchment with 52 $km^2$ land area where 14 automated weather stations are in operation. This note introduces the system and describes the major modules in detail. By linking regional AWS networks, a feasibility for this system as an early warning system is also discussed.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.15 no.4
• /
• pp.320-331
• /
• 2013

The National Center for AgroMeteorology (NCAM) has designed a risk management solution for individual farms threatened by the climate change and variability. The new service produces weather risk indices tailored to the crop species and phenology by using site-specific weather forecasts and analysis derived from digital products of the Korea Meteorological Administration (KMA). If the risk is high enough to cause any damage to the crops, agrometeorological warnings or watches are delivered to the growers' cellular phones with relevant countermeasures to help protect their crops against the potential damage. Core techniques such as scaling down of weather data to individual farm level and the crop specific risk assessment for operational service were developed and integrated into a cloud based service system. The system was employed and implemented in a rural catchment of 50 $km^2$ with diverse agricultural activities and 230 volunteer farmers are participating in this project to get the user-specific weather information from and to feed their evaluations back to NCAM. The experience obtained through this project will be useful in planning and developing the nation-wide early warning service in agricultural sector exposed to the climate and weather extremes under climate change and climate variability.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.6 no.2
• /
• pp.140-147
• /
• 2004

Agrometeorological information is essential in many agricultural decisions if it reaches the user in a timely and appropriate manner. Agriculture is the backbone to local, regional, and global economic development. Thus, strengthening agrometeorological application to diverse agricultural sectors will benefit economic development. This paper discusses three distinct organizational minions that all share the same need for improved information technology. The World Meteorological Organization's (WMOs) Commission for Agricultural Meteorology (CAgM) has global responsibility for improved agrometeorological services of Members to aid agricultural production and to conserve natural resources. The United States Department of Agriculture, World Agricultural Outlook Board, publishes monthly World Agricultural Supply and Demand Estimates, considered to be a benchmark for both government and industry in production and trade decisions. The National Drought Policy Commission (NDPC), created by an act of the United States Congress, formulated a national drought policy based on preparedness rather than on crisis management. All three organizations recognize the need for IT applications in agricultural meteorology and have been active in implementing this technology. The development of information technology offers new means of dissemination of agrometeorological products. World Agrometeorological Information Service (WAMIS) has taken advantage of the global Internet application to offer WMO Members a dedicated web server to host agrometeorological bulletins and training modules.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.14 no.2
• /
• pp.53-62
• /
• 2012

Demand for high resolution weather data grows in the agriculture and forestry fields. Local Analysis and Prediction System (LAPS) can be used to analyze the local weather at high spatial and temporal resolution, utilizing the data from various sources including numerical weather prediction models, wind or temperature profilers, Automated Weather Station (AWS) networks, radars, and satellites. LAPS has been set to analyze weather elements such as air temperature, relative humidity, wind speed, and wind direction every hour at the spatial resolution of $100m{\times}100m$ for Gyeonggi-do on near real-time basis. The AWS data were revised by adding the agricultural field AWS data (33 stations) in addition to the KMA data. The analysis periods were from 1 to 31 August 2009 and from 15 to 21 February 2010. The comparison of the LAPS output showed the smaller errors when using the agricultural AWS observation data together with the KMA data as its input data than using only either the agricultural or KMA AWS data. The accuracy of the current system needs improvement by further optimization of analyzing options of the system. However, the system is highly applicable to various fields in agriculture and forestry because it can provide site specific data with reasonable time intervals.

• Korean Journal of Remote Sensing
• /
• v.39 no.6_1
• /
• pp.1427-1435
• /
• 2023

Vegetation indices based on selected wavelength reflectance measurements are used to represent crop growth and physiological conditions. However, the anisotropic properties of the crop canopy surface can govern spectral reflectance and vegetation indices. In this study, we applied an ensemble of bidirectional reflectance distribution function (BRDF) models to high-resolution Sentinel-2 satellite imagery and compared the differences between correction results before and after reflectance. In the red and near-infrared (NIR) band reflectance images, BRDF-corrected outlier values appeared in certain urban and paddy fields of farmland areas and forest shadow areas. These effects were equally observed when calculating the normalized difference vegetation index (NDVI) and 2-band enhanced vegetation index (EVI2). Furthermore, the outlier values in corrected NIR band were shown in pixels shadowed by mountain terrain. These results are expected to contribute to the development and improvement of BRDF models in high-resolution satellite images.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.55 no.3
• /
• pp.214-219
• /
• 2010

In order to evaluate the benefits of global warming on the double cropping with staple crops in North-Korea, four aspects such as the increasing rate of air temperature, the wintering temperatures for winter crops, the causing temperature of cool injury to rice and the securing of accumulated temperature for the double cropping in the different agricultural climate zones were analyzed by comparing the differences between the past 22 years from 1973 to 1994 and the recent 5 years from 2002 to 2006. The warming rate in recent daily mean air temperature of $8.96^{\circ}C$ in North Korea was higher by $0.64^{\circ}C$ than that in the past with large regional variations ranging from $1.06^{\circ}C$ in Samjiyeon of northern inland semi-alpine zone to $12.26^{\circ}C$ in Jangjeon of east central coastal zone. With the accumulated temperatures of more than $3,150^{\circ}C$ and $2,650^{\circ}C$, it was possible to apply the double cropping patterns with winter wheat and for cropping patterns with spring potato, respectively, to the whole region except for the northern inland semi-alpine zone. However, the wintering temperature higher than $-15^{\circ}C$ of average daily minimum air temperature of January, cropping patterns were impossible to northern inland semi-alpine zone and most regions of the northern mountainous zone. The days passed by below $17^{\circ}C$ in daily mean air temperature, causing the spikelet sterility at meiotic stage of rice in July, were a lot recorded from 21 to 29 days in northern inland semi-alpine zone and from 2 to 10 days in east-northern coastal zone, respectively. Therefore, a reasonable utilization of heat / temperature resources would relieve the limiting factors in double cropping for stable production of staple crops in North-Korea.