Influence of sewage sludge, as a substrate, in the plasticity of functional characteristics of plants Vicente Elício Porfiro Sales Gonçalves da Silva & Patrícia Marques Carneiro Buarque & Wanessa Nepomuceno Ferreira & Hugo Leonardo de Brito Buarque & Maria Amanda Menezes Silva Received: 11 December 2017 /Accepted: 16 April 2018 # Springer International Publishing AG, part of Springer Nature 2018 Abstract This work aimed to evaluate the effect of sew- age sludge application as fertilizer on the plasticity of functional characteristics of species commonly found in the Caatinga. The research was developed in the nursery of the Federal Institute of Education, Science and Technology of Ceará (IFCE), Quixadá campus, located in northeastern Brazil. Three treatments were applied: raw sludge, sani- tized sludge, and no manipulation. In each treatment, five species were planted, each with five individuals, totaling 75 individuals, which were tagged, and 4 months after germination, they were destroyed to obtain dry matter content (TMSF) from leaf, stem (TMSC), fine root (TMSRF), and thick root (TMSRG); leaf area; height and diameter of the seedling; and length above and below the ground. The sanitized sludge was responsible for giv- ing higher values for leaf area, height of the seedlings, and diameter and length of stem and root. However, the dry matter content of the fine roots was higher in the treatment without manipulation. At the community level, as TMSRG increased, TMSC also increased, the same occurred be- tween TMSRG and TMSRF, TMSC and TMSRF, and stem length and leaf area. In the treatment without manip- ulation, there was a positive correlation between leaf area, height and plant diameter, and negative correlation be- tween root length and plant diameter. Thus, it can be concluded that the use of sanitized sludge is a good tool to increase the availability of soil resources, conferring to individuals’ greater dry matter content, greater leaf area, and higher height and diameter above the ground. Keywords Biosolids . Caatinga . Functional Ecology . Trade-off Introduction Functional characteristics are function markers, predicting differential inversions in morphological and physiological characteristics, which influence in surviv- al, growth, and reproduction of plant species (Garnier and Navas 2012). These characteristics are indicators that respond to resource availability and environmental conditions, since the environment will act as a filter, Environ Monit Assess (2018) 190:307 https://doi.org/10.1007/s10661-018-6691-6 V. E. P. S. G. da Silva (*) : H. L. d. Buarque Federal Institute of Education, Science and Technology of Ceará, IFCE Campus Fortaleza, Fortaleza, Brazil e-mail: vicenteelicio@gmail.com H. L. d. Buarque e-mail: hbuarque@yahoo.com.br P. M. C. Buarque : W. N. Ferreira Federal University of Ceará, Fortaleza, Brazil P. M. C. Buarque e-mail: pmcbuarque@gmail.com W. N. Ferreira e-mail: wanessa.nepomuceno@ufca.edu.br M. A. M. Silva Federal University of Cariri - UFCA, Institute of Educator Education - IFE, Street Olegário Emídio de Araújo, Center, 63260000 Brejo Santo, CE, Brazil e-mail: amandamenezesmsn@hotmail.com