Molecular Soil Biology 2025, Vol.16, No.1, 1-15 http://bioscipublisher.com/index.php/msb 4 3 Soil Testing and Nutrient Management Planning 3.1 Importance of soil testing to determine nutrient levels and deficiencies Soil testing is an essential tool for identifying the nutrient status of agricultural land. By analyzing the levels of key nutrients such as nitrogen (N), phosphorus (P), and potassium (K), as well as micronutrients like zinc (Zn) and magnesium (Mg), farmers can make informed decisions about fertilization. Regular soil testing allows for a detailed understanding of soil fertility, helping to determine which nutrients are deficient or present in excess. This ensures that crops receive the right amount of nutrients at the right time, improving growth and yield potential. The absence of soil testing can lead to either nutrient deficiencies, which limit growth, or nutrient excesses, which can cause environmental problems such as water contamination from leaching (Mohamed et al., 2023). Beyond identifying nutrient levels, soil testing can also provide information on pH, soil structure, and organic matter content. These factors significantly affect nutrient availability to plants. For example, in soils with low pH (acidic soils), certain nutrients like phosphorus may become less available, reducing crop productivity. Soil testing helps to detect these issues, allowing farmers to adjust pH levels by applying lime or other amendments to optimize nutrient availability (Hedley, 2015). Regular soil testing not only helps maintain optimal soil health but also ensures that the correct balance of nutrients is achieved throughout the growing season. Moreover, soil testing is particularly important for sustainable farming practices. By applying nutrients based on soil testing results, farmers can avoid the over-application of fertilizers, which often leads to nutrient runoff and environmental degradation. In regions where agriculture is a major contributor to nutrient pollution, such as nitrogen leaching into groundwater or phosphorus runoff into rivers and lakes, soil testing plays a crucial role in environmental protection. Studies have shown that nutrient management plans based on soil testing can reduce the need for fertilizers by as much as 30%, lowering costs and mitigating environmental risks (Madhumathi et al., 2020). 3.2 Use of Nutrient Management Plans Tailored to Specific Soil Conditions Once soil testing results are obtained, the next step is to develop nutrient management plans that are tailored to the specific conditions of the soil. Each field or section of land can have varying nutrient needs depending on factors such as soil type, organic matter content, moisture levels, and the specific crop being grown. A one-size-fits-all approach to fertilization is often inefficient, as different areas of the same farm may require different amounts of nutrients. For example, sandy soils tend to leach nutrients more quickly and may require more frequent but smaller applications of fertilizers, while clay-rich soils hold nutrients longer but may need careful management to avoid waterlogging (Shubha, 2018). Nutrient management plans help optimize the timing, placement, and quantity of fertilizer applications to match the specific needs of the soil and the crop. These plans are based on the crop's growth stages and nutrient requirements, ensuring that the plants receive the necessary nutrients when they need them most. For instance, nitrogen is often applied in split doses, with the first application at planting and subsequent applications timed to critical growth stages, such as during tuber initiation for potatoes. This approach minimizes the risk of nutrient loss due to leaching or runoff, ensuring that nutrients are available when the crop is most capable of absorbing them (Mohamed et al., 2023). Moreover, nutrient management plans can incorporate organic fertilizers, such as compost or manure, alongside synthetic fertilizers. This integrated approach provides a more balanced nutrient supply, improving soil health and structure over the long term. The combination of organic and inorganic fertilizers not only boosts crop productivity but also enhances the soil's ability to retain moisture and nutrients, reducing the need for additional fertilizer inputs in the future (Shubha, 2018). Tailoring these plans to specific soil conditions helps improve nutrient use efficiency, leading to higher yields and more sustainable farming practices. In Deqing, Zhejiang China, the technology of soil testing and formulated fertilization has been implemented for more than a decade. In 2024, the county implemented 280 soil sampling and testing points for major crops, and
RkJQdWJsaXNoZXIy MjQ4ODYzNA==