Читать книгу Soil Health Analysis, Set - Группа авторов - Страница 47

Documenting benefits from soil health approaches first requires defining what is the benefit of interest and then selecting ways to measure and document the response. The principles associated with soil health are not new as evident by centuries of soil management, conservation, condition, tilth, quality, and other terms. Among the well‐known and generally accepted approaches for improving soil health are the goals of keeping the soil covered, reducing disturbance, maintaining plants year‐round, and diversifying the mix of plant species. Implementing these goals can increase the quantity of plant residues and root exudates returned to the soil, boost microbial activity, and ultimately lead to a cascade of soil improvements, including increased SOM, more stable soil aggregation, and efficient nutrient cycling. How well these benefits can be documented depends on the magnitude of change (generally determined by inherent soil properties and/or initial conditions) as well as the type of soil health test selected (i.e., in‐field, commercial or research laboratory, remote sensing), and the scale at which comparisons are to be made and meaningful (i.e., from landscapes down to finely sieved and crushed soil samples). Interactions between inherent and dynamic soil properties can also make documenting soil health benefits difficult, since spatial and temporal variability can mask potential changes associated with new soil and crop management practices, such as annual cover crop establishment, which must be given adequate time for measurable effects to occur. Extreme weather conditions, such as too much or too little rainfall, early or late frost, or above normal temperatures can hinder the effectiveness of new or alternative management systems and prevent them from becoming established and changing soil properties in subsequent years. Without question, researchers have documented numerous benefits from soil health approaches. As the concept evolves, the core questions of defining what constitutes an important benefit and selecting reproducible methods to measure that benefit will remain a constant challenge and an important research goal.