The use of sewage sludge hydrochar for improving soil fertility in the Cerrado region of Brazil – scientific effects and social acceptance Dissertation zur Erlangung eines Doktorgrades (Dr.-Ing.) in der Fakultät für Architektur und Bauingenieurwesen der Bergischen Universität Wuppertal vorgelegt von Tatiane Medeiros Melo aus Goiânia/Goiás, Brasilien Wuppertal 2019 i Table of Content List of Figures ................................................................................................................................................ I List of Tables .............................................................................................................................................. III List of Abbreviations .................................................................................................................................. IV Summary ..................................................................................................................................................... VI Zusammenfassung ....................................................................................................................................... IX 1 INTRODUCTION ................................................................................................................................. 1 1.1 JUSTIFICATION OF THE RESEARCH ................................................................................................ 1 1.2 THE BRAZILIAN SOIL TERRITORY ................................................................................................. 3 1.3 BACKGROUND INFORMATION ON AGRICULTURE IN BRAZIL AND CERRADO REGION .................. 7 1.4 HYDROTHERMAL CARBONIZATION ............................................................................................. 11 1.5 USE OF BIOSOLIDS-DERIVED CHARS AS SOIL AMENDMENT ........................................................ 14 1.6 GENERAL AND SPECIFIC OBJECTIVES .......................................................................................... 18 1.7 THESIS STRUCTURE ..................................................................................................................... 18 1.8 REFERENCES ............................................................................................................................... 21 2 EFFECT OF BIOSOLIDS HYDROCHAR ON TOXICITY TO EARTHWORMS AND BRINE SHRIMP .............................................................................................................................................. 31 2.1 ABSTRACT ................................................................................................................................... 32 2.2 INTRODUCTION ............................................................................................................................ 32 2.3 MATERIAL AND METHODS .......................................................................................................... 34 2.3.1 Sewchar properties ............................................................................................................... 34 2.3.2 Earthworm acute toxicity test (Eisenia foetida) .................................................................. 36 2.3.3 Brine shrimp (Artemia salina) acute toxicity test procedure ............................................... 38 2.3.4 Statistical analyses ............................................................................................................... 38 2.4 RESULTS AND DISCUSSION ......................................................................................................... 39 2.4.1 Assessment of Sewchar in terms of acute toxicity to earthworms (Eisenia foetida) ........... 39 2.4.2 Lethality behavior of brine shrimps (Artemia salina) after Sewchar process water filtrate exposure ............................................................................................................................... 44 2.5 CONCLUSIONS ............................................................................................................................. 45 2.6 ACKNOWLEDGMENT ................................................................................................................... 46 2.7 REFERENCES ............................................................................................................................... 46 3 PLANT AND SOIL RESPONSES TO HYDROTHERMALLY CONVERTED SEWAGE SLUDGE (SEWCHAR) ....................................................................................................................................... 52 3.1 ABSTRACT ................................................................................................................................... 53 3.2 INTRODUCTION ............................................................................................................................ 53 3.3 MATERIAL AND METHODS .......................................................................................................... 54 3.3.1 Sewchar ................................................................................................................................ 54 3.3.2 Soil ....................................................................................................................................... 55 3.3.3 Pot experiment ..................................................................................................................... 55 3.3.4 Soil sampling and analysis ................................................................................................... 56 3.3.5 Plant tissue sampling and analysis ....................................................................................... 56 3.3.6 Statistical analyses ............................................................................................................... 56 3.4 RESULTS AND DISCUSSION ......................................................................................................... 56 3.4.1 Effect of Sewchar and mineral fertilizer on plant growth ................................................... 56 3.4.2 Effect of Sewchar and mineral fertilizer on soil properties ................................................. 60 3.4.3 Threshold of Sewchar applications ...................................................................................... 66 3.5 CONCLUSIONS ............................................................................................................................. 68 3.6 ACKNOWLEDGMENT ................................................................................................................... 68 3.7 REFERENCES ............................................................................................................................... 68 4 MANAGEMENT OF BIOSOLIDS-DERIVED HYDROCHAR (SEWCHAR): EFFECT ON PLANT GERMINATION, AND FARMERS' ACCEPTANCE ........................................................ 74 4.1 ABSTRACT ................................................................................................................................... 75 4.2 INTRODUCTION ............................................................................................................................ 75 4.3 MATERIAL AND METHODS .......................................................................................................... 77 4.3.1 Sewchar preparation ............................................................................................................ 77 4.3.2 Chemical properties of biosolids and Sewchar .................................................................... 78 4.3.3 Physical properties of biosolids and Sewchar ..................................................................... 79 4.3.4 Soil properties ...................................................................................................................... 80 4.3.5 Germination experiment ...................................................................................................... 82 4.3.6 Survey .................................................................................................................................. 82 4.3.7 Data analyses and statistics .................................................................................................. 83 4.4 RESULTS AND DISCUSSION ......................................................................................................... 84 4.4.1 Biosolids and Sewchar chemical properties ........................................................................ 84 4.4.2 Biosolids and Sewchar physical properties ......................................................................... 91 4.4.3 Germination experiment ...................................................................................................... 94 4.4.4 Survey .................................................................................................................................. 97 4.5 CONCLUSIONS ........................................................................................................................... 101 4.6 AKNOWLEDGMENT ................................................................................................................... 102 4.7 REFERENCES ............................................................................................................................. 102 5 SUMMARIZING DISCUSSION, CONCLUSIONS, AND OUTLOOK ......................................... 111 5.1 MAIN RESEARCH