Soil‐test biological activity with short‐term and long‐term carbon contributions

Abstract

Soil-test biological activity (STBA) is a key indicator of soil health because of its relevance to ecosystem processing, broad applicability, and simple and rapid analysis. Short-term and long-term influences of carbon (C) availability on STBA were assessed. A short-term factor was root-derived C inputs from a sudangrass (Sorghum × drummondii) test crop grown under greenhouse conditions. Longterm factors were from soil at two depths in three sections of a field varying in soil texture and exposed to 16 yr of different pasture-crop rotation management. Soiltest biological activity was determined after 0, 14, 21, 31, and 45 d of greenhouse growth. Total variation in STBA was 7% from the short-term factor and 81% from the long-term factors. Soil depth was the primary long-term factor influencing STBA (57%) and soil texture was intermediate (24%). Results indicate that shortterm changes in STBA are important but modest compared with variations due to soil depth and texture. 1 INTRODUCTION Soil is a fundamental natural resource that sustains agriculture and the growing number of people inhabiting the planet (Janzen et al., 2011). Humanity has a responsibility to maintain and improve soil conditions so that future generations will be able to share in this life-supporting natural resource. With appropriate care, soil resources are renewable. However, with reckless management, soil resources can dwindle into barren deserts, rocky fields, or highly contaminated wastelands (Montgomery, 2007). Soil can be managed to meet our needs for today and the future (Franzluebbers, 2010) if we follow some guiding principles to minimize disturbance, keep soil covered, provide living roots for as much of the year as possible, and enhance Abbreviations: STBA, soil-test biological activity. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Utilization and limitations of soil health metrics in Missouri corn production decisions

“…This highlights this metric's unique sensitivity to site-specific environmental conditions, landscapes, soil properties, and management practice. This observation aligns with other reports that soil respiration is susceptible to site-specific characteristics interfering with scaling to regional implementation (Franzluebbers and Assmann, 2020;.…”

“…Various soil processing and analysis protocols are available, though all involve rewetting of air-dried soil and capturing and measuring the flush of CO2 released during the predetermined incubation period (Franzluebbers et al, 1996(Franzluebbers et al, , 2000Franzluebbers & Veum, 2020). In the literature, this analysis is sometimes referred to as soil respiration, mineralizable C, or soil-test biological activity (Moebius et al, 2007;Hurisso et al, 2018a;Franzluebbers & Assmann, 2020). For the duration of this paper, the term soil respiration is used when referring to this measurement.…”

“…Additional applications include soil productivity Wade et al, 2020a), changes in soil function induced by management practices , and potential soil microbial activity (Franzluebbers et al, 2000;Franzluebbers, 2020a). Improving soil respiration with management changes can be complicated by native soil and environmental properties (Dou et al, 2008;Franzluebbers & Assmann, 2020;Franzluebbers & Pershing, 2020). summarized that soil respiration rate reflects management practices that stimulate or promote mineralization of soil nutrients.…”

“…Despite these challenges soil respiration is well suited as an effective regional measurement for cover crop benefits upon soil health. This derives from soil respirations sensitivity to recent residue and organic inputs that promote mineralization processes Franzluebbers and Assmann, 2020).…”