Significance: Understanding and tracking nature’s contributions to people provides critical feedback that can improve our ability to manage earth systems effectively, equitably, and sustainably. Declines in biodiversity and ecosystem functions over the past 50 y have decreased the ability of nature to contribute to quality of life. Changes in technology and adaptation in social systems has partially offset the negative impacts of environmental change on quality of life, but downward trends have still occurred for many categories of nature’s contributions.
Research results still vary, especially between locations, on the effects of agricultural practices on soil chemical properties and crop yield, and not all reasons for the variation are fully understood. Thus, this study investigated the influence of tillage, cover crop and crop rotation management practices on selected soil chemical properties. The study was conducted on a silt-loam soil in central Missouri during the 2011 to 2013 growing seasons. The soil was managed by moldboard plow tillage at two levels (tillage [till] vs. no-tillage [NT]). Cover crop management included cereal rye (Secale cereale) at two levels (cover crop [CC] vs. no cover crop [NC]). The main crops that were grown were a corn (Zea mays L.) and soybean (Glycine max L.) rotation. The soil samples were collected each year at 0–10 cm, 10–20 cm, 20–40 cm and 40–60 cm depths for the analysis of soil chemical properties. The results showed that after 3 years of study, the relative increase in percent soil organic matter (OM) was 4% under the no-till management as compared with moldboard plow tillage. In addition, the relative change in the percentage of OM was 8% greater in the CC management compared with NC. Furthermore, the results show a significant improvement (p = 0.0304) in total carbon with a combination of no-till management and a corn/soybean rotation as compared with continuous corn and soybean. The interaction effects of the management practices on the soil chemical properties were difficult to predict throughout the study.
1 July 2019 in Journal of Environmental Management
Livestock production is important for food security, nutrition, and landscape maintenance, but it is associated with several environmental impacts. To assess the risk and benefits arising from livestock production, transparent and robust indicators are required, such as those offered by life cycle assessment. A central question in such approaches is how environmental burden is allocated to livestock products and to manure that is re-used for agricultural production. To incentivize sustainable use of manure, it should be considered as a co-product as long as it is not disposed of, or wasted, or applied in excess of crop nutrient needs, in which case it should be treated as a waste. This paper proposes a theoretical approach to define nutrient requirements based on nutrient response curves to economic and physical optima and a pragmatic approach based on crop nutrient yield adjusted for nutrient losses to atmosphere and water. Allocation of environmental burden to manure and other livestock products is then based on the nutrient value from manure for crop production using the price of fertilizer nutrients. We illustrate and discuss the proposed method with two case studies.
1 December 2021 in The Egyptian Journal of Remote Sensing and Space Sciences
Water is usually the most limiting factor in agricultural grain crop production. Various agricultural management practices, such as tillage and use of cover crops, have the potential to influence water infiltration into soil. This study was conducted on a Waldron silt loam (fine, smectitic, calcareous, mesic Aeric Fluvaquents) soil to evaluate the influence of cover crop and tillage management on in situ infiltration. The field site included three replicate blocks in a randomized complete block design with each plot measuring 21.3 m (69.9 ft) length and 12.2 m (40 ft) width. The two treatment factors included cover crop at two levels (cereal rye [Secale cereale] cover crop [CC] versus no cover crop [NC]) and tillage at two levels (moldboard plow tillage [Till] versus no-tillage [NT]). Continuous corn (Zea mays L.) was grown. Infiltration rates were measured in all the treatments using a Mariotte system with single-ring infiltrometers during the 2014 and 2015 growing seasons. Water infiltration parameters were estimated using the Parlange and Green-Ampt infiltration equations. Parlange and Green-Ampt models appeared to fit measured data well with coefficient of variation ranging from 0.92 to 0.99. In 2014, the saturated hydraulic conductivity (KS) parameter value determined from the Parlange model was 30.4 mm h−1 (1.2 in hr−1) for NT, about 42% greater than Till. The KS parameter value determined from the Green-Ampt model was 25.9 mm h−1 (1 in hr−1) for NT, about 54% greater than Till. In 2015, the sorptivity (S) parameter value determined from the Parlange model was 38.6 mm h−0.5 (1.5 in hr−0.5) for CC, about 82% greater than NC. The S parameter value determined from the Green-Ampt model was 34 mm h−0.5 (1.3 in hr−0.5) for CC, about 90% greater than NC. Cover crop management can increase water infiltration, which can improve soil quality and enhance the sustainability of crop production systems.