Excessive amount of nutrients have been used to farmland since the 1980s, when the intensive farming method called "High-Input, High-Yield" was expanded in earnest. So far several programs of environmentally friendly agricultural policies have been pursued to reduce the amount of chemical fertilizer use and to properly manage livestock manures. However, due to the lack of effective measures taken to reduce nutrient excess, Korea topped the list of nitrogen balance per unit area of cultivated land among the OECD member countries. The increasing nutrient excess pollutes surface as well as underground water. In addition, it causes soil acidification, deteriorates the ecological system, and increases greenhouse gas emission, thereby generating substantial amount of social costs. As a decisive measure to find out the nutrient balance status by region and properly resolve the nutrient excess problem, the Korean government announced its plan to introduce Region-based Maximum Nutrients Loading System (RMNLS) from 2007. In this note, this study is aimed to map out and suggest detailed plans to implement the RMNLS in a full scale.
This report is divided into six chapters. In Chapter 1, the necessity and purpose of the study are introduced, and the previous studies are reviewed. Chapter 2 takes a look at the meaning and significance of the maximum nutrients loading system. Chapter 3 explains the maximum nutrients loading system and the theory of nutrient balance analysis. In Chapter 4, the nutrient balance status of farmland is analyzed, and the analytical results of nutrient balance at the country and regional level are described. Chapter 5 describes the detailed implementation plan for the RMNLS, including the basic directions, prerequisites, and detailed action plans. It also proposes the plan for sustainable development of the RMNLS. Lastly, Chapter 6 summarizes the study and gives the conclusion.
To draw up the detailed implementation plan for the RMNLS, the review of previous studies, the collection of opinions from agricultural, livestock and academic sectors regarding the introduction of new RMNLS, the development of the program to calculate regional based nutrient balance, and the establishment of the regional nutrient balance database were adopted as study methods. To calculate the nutrient balance, the Excel Macro program was utilized to develop the Regional Nutrients Accounting System (ReNAS).
When nutrient balance indicator at the national level was calculated, it turns out that while the cultivating land size has been on the continuous decline, the chemical fertilizer consumption was not reduced accordingly. It was also found that because of the increasing number of livestock operations, the nutrient balance, which has continued to go down since 1990, turned around and went up again since 2001. The analysis of farmland nutrient balance shows that the nutrient balance is quite different by region. When it comes to nitrogen balance, the nutrient amount per unit area of cultivated land in excess of the crop nutrient requirement amount was the highest in the Jeonbuk province with 157kg/ha, which is 132.4 percent higher than the appropriate level. The Chungnam province and the Gyeonggi province came next with 154.4kg/ha (131.7 percent) and 138.3kg/ha (111.3 percent) respectively.
The analysis of nutrient balance of cities and counties in each province has found that regions show a huge difference in nutrient management status. For example, there were some areas where nutrients are managed well below the acceptable nutrient use level, while other areas were subject to special nutrient management, since they use nutrients three to four times higher than the acceptable level. Therefore, it was found that a decisive measure shall be taken to put excess nutrients under control.
The basic direction of the newly introduced RMNLS is to comprehensively manage chemical fertilizers and livestock manures under the prevention principle and takes the three-step measures, including preparation, implementation, and settle-down, until the system takes a firm root. To ensure transparent and fair system operation, the Internet-based information management and the experts' review process on effective handling of the issues raised are suggested.
The study suggests the preconditions for smooth operation of the RMNLS. They include the building of relevant statistical database for nutrient balance calculation, the setup of a livestock unit to accurately calculate livestock manure sources, the distribution of the ReNAS to understand regional nutrient balance, the establishment & operation of the "Monitoring Team of Maximum Nutrients Loading System (tentatively named)" and the preparation of laws and institutions for the RMNLS implementation.
As the first step of the RMNLS implementation plan, the study proposed the calculation of regional nutrient balance indicator with ReNAS, the selection of materials subject to nutrient management based on nitrogen contents first and then the shift to phosphorous content when the RMNLS settles down to a certain degree. According to the excess amount of materials subject to nutrient management by region, when compared with the national average nutrient demand, if the nutrient excess rate is less than 30 percent, the areas are classified as the "Areas of good nutrient management." If the nutrient excess rate is between 30 percent and 100 percent, the areas are classified as the "Areas for nutrient management motivation". Furthermore, the areas, whose nutrient excess rate is above 100 percent, are classified as the "Areas for special nutrient management". Among the areas for special nutrient management, if the excess rate is between 100 percent and 150 percent, they are classified as "Area I for special nutrient management," and if the excess rate is 150 percent or above, they are classified as "Area II for special nutrient management."
Based on the nutrient balance index by region, the reduction target of concerned regions shall be set, and using the evaluation of performance every two years, the maximum nutrients loading reduction goal shall be renewed. For practical operation of the RMNLS, the "Basic Guideline for the RMNLS" shall be prepared under the order of the Ministry of Agriculture and Forestry (MAF). The Guideline shall include general rules, definitions of terms, types of materials subject to nutrient management, the management goal of the RMNLS, the method of calculating nutrient balance, the excess nutrient reduction plan, the basic plan, and the performance report preparation.
In relation to the implementation of the RMNLS, relevant organizations shall divide their roles. The MAF shall prepare and transfer the basic guideline for the RMNLS and designate the areas subject to nutrients management and special areas under management depending on the level of nutrient balance by region. Considering specific conditions by region, mayors and county heads of local autonomous governments shall draw up and submit the RMNLS implementation plan by region. The MAF Minister shall approve the implementation plan for the RMNLS submitted by cities and counties after they are reviewed by the "Maximum Nutrients Loading System Monitoring Team."
To make the RMNLS properly work, the data reported for nutrient balance calculation by each region shall be verified. In relation to the operation of the RMNLS, each year a map of nutrient balance status of all cities and counties shall be prepared and made public on the Internet website. This will help policy makers, farmers, and the general public easily understand the level of efforts made by each region to reduce the environmental loads and control excessive nutrients
Depending on the level of excess nutrient reduction, differentiated incentives shall be provided. Therefore, to the areas which achieve substantial excess nutrient reduction under the excessive nutrient management plan, appropriate incentives, including the prioritized policy fund allocation, shall be provided. To the regions, which are unable to reduce excess nutrients, shall be imposed with punishments such as the end of policy fund support.
Prior to the full-fledged and nationwide implementation of the RMNLS, it would be better to select a few areas which have high nutrient excess rate (1~2 cities or counties per province) for pilot test to maximize the policy results. To be utilized as a valid program to build the environmentally friendly agricultural system, diverse measures shall be mapped out to properly divide roles among relevant entities and enable local autonomies to properly manage their nutrient balance. In the mid to long term, to make sure that the RMNLS is utilized as a core program for the environmentally friendly agricultural policy, the plan to establish a dedicated organization shall be thoroughly reviewed.
Researchers: Chang-Gil Kim, Tae-Young Kim, and Yong-Kwang Shin
E-mail address: changgil@krei.re.kr