Contents lists available at ScienceDirect Applied Soil Ecology journal homepage: www.elsevier.com/locate/apsoil Impact of inoculation with local effective microorganisms on soil nitrogen cycling and legume productivity using composted broiler litter Laura Ney a , Dorcas Franklin a, ⁎ , Kishan Mahmud a , Miguel Cabrera a , Dennis Hancock a , Mussie Habteselassie b , Quint Newcomer c , Subash Dahal a a Department of Crop and Soil Sciences, University of Georgia, Miller Plant Sciences Building, 3111 Carlton St Bldg, Athens, GA 30602, United States of America b Department of Crop and Soil Sciences, University of Georgia Griffin Campus, 1109 Experiment Street, Griffin, GA 30223, United States of America c Odum School of Ecology, University of Georgia, 140 E Green St, Athens, GA 30602, United States of America ARTICLE INFO Keywords: N mineralization Nematodes Soil biome Microorganismos de la montaña Local effective microorganisms Legume ABSTRACT Local effective microorganism (LEM) is an inoculant produced using leaf litter collected from forest floors near the location where it is to be utilized. While this locally-sourced inoculant is used around the world, more research is needed to fully understand the potential benefits or drawbacks of its use in agricultural systems. The objectives of this study were to observe the effects of combining LEM with composted broiler litter to fertilize edamame (Glycine max L.) on plant-available nitrogen, nematode trophic group communities, and soybean productivity. The study was carried out in a randomized, complete block design on piedmont soils in the southeastern United States comparing broiler litter composted with LEM, False-LEM or water (Control) treat- ments which were applied at the beginning of each growing season (June 2015, 2016, 2017). In the first year of the study, soil (0–10 cm) that received the LEM treatment mineralized greater amounts of N and mineralized N faster than CONT soils (P = 0.0665 and P = 0.0717), respectively, during one week of incubation. In year 2 (2016) plots experienced drought stress, with soil moistures as low as 2%. In LEM plots soil samples taken during the drought contained significantly greater populations of all nematodes, excluding Mononchidae when com- pared to the other treatments. When calculated per unit of soil N, measured after application of treatments, no differences in edamame soybean yield were observed between treatments. Combining LEM with composted broiler litter jump-started N mineralization early in growing seasons and maintained abundance of multiple nematode trophic groups during drought. This signifies LEM's potential to strengthen a soil's food web resistance to drought stress – providing more security for a functional agroecosystem under uncertain climate conditions. 1. Introduction Decomposition and therefore composting are microbially driven processes. The abundance and community make-up of these often in- visible components of the soil ecosystem determine the rate that or- ganic material is broken down and the components into which the material is ultimately broken down into. This means that the speed that composting occurs as well as the quality of the resulting compost is due not only to the materials being composted but also the microbes present during composting. Local effective microorganisms (LEM), also known as microorganismos de la montaña in Latin America, is a concentrated solution of microbes that are collected and cultured from healthy, un- disturbed forest floor ecosystems near the farms where the LEM is being produced and applied. LEM is a homemade adaptation of EM™, a commercial microbial inoculant developed by Dr. Teruo Higa at the University of Ryukyus in Okinawa, Japan. According to the EM Research Organization (www.emrojapan.com/how/), Dr. Higa's EM™ contains beneficial, synergistic organisms such as lactic acid bacteria, yeasts and phototrophic bacteria (Higa, 2000). EM™ is also reported to increase composting efficiency by decreasing the length of time needed to complete composting and by decreasing the number of times com- post must be turned. It also is said to reduce foul odors by neutralizing odor causing components such as ammonia and to decrease nutrient loss in the form of ammonia and CO 2 by instead processing proteins into amino acids that can be taken up and easily metabolized by plants (Higa and Parr, 1994). While EM™ contains specific strains of organisms cultured in a lab and LEM is cultured from an array of microorganisms collected from the surrounding environment, it has been confirmed that the same active groups of organisms, such as lactic acid bacteria, ni- trogen fixing bacteria and photosynthetic bacteria, have been found in https://doi.org/10.1016/j.apsoil.2020.103567 Received 21 February 2019; Received in revised form 16 February 2020; Accepted 20 February 2020 ⁎ Corresponding author. E-mail address: dfrankln@uga.edu (D. Franklin). Applied Soil Ecology 154 (2020) 103567 0929-1393/ © 2020 Published by Elsevier B.V. T