Download Soil Science Terminology and Concepts and more Quizzes Agricultural engineering in PDF only on Docsity! TERM 1 What is Particle Density? DEFINITION 1 The solid space, excluding the pore space TERM 2 What is Bulk Density DEFINITION 2 The solid space + pore space TERM 3 What number should you use when assuming Particle Density? DEFINITION 3 2.65 TERM 4 Wt of dry soil / Vol. of solids DEFINITION 4 Particle density TERM 5 Wt. of dry soil / vol. of bulk soil = ? DEFINITION 5 bulk density TERM 6 What is the bulk density range of clay? DEFINITION 6 1.2 -1.3 g/cm3 TERM 7 What is the bulk density range of a loam? DEFINITION 7 1.3 - 1.4 TERM 8 What is the bulk density range of a sand? DEFINITION 8 1.5 + TERM 9 Bulk Density / Particle Density X 100 = ? DEFINITION 9 % solid space TERM 10 100 - solid space = ? DEFINITION 10 % pore space TERM 21 Describe bad tilth DEFINITION 21 Clay or Sand texturePlaty, Massive, single-grained structuretoo low or too high of bulk densitytoo compacted or too much space for pore space TERM 22 What should be added to improve soil tilth? DEFINITION 22 Add organic matter TERM 23 __________ is organic matter broken down beyond recognition. DEFINITION 23 Humus TERM 24 What can replace Silicon (Si4+) in a Silica Tetrahedron? DEFINITION 24 Aluminum (Al3+) TERM 25 What can replace Aluminum in the Aluminum Octahedral? DEFINITION 25 Mg2+Zn2+Fe2+Fe3+But Mg2+ is the most common. TERM 26 What is the substitution called? DEFINITION 26 Isomorphicsubstitution TERM 27 __________ clay is used for porcelain and pottery. DEFINITION 27 Kaolinite TERM 28 Smectites are ___ : ___ _______ clays DEFINITION 28 2:1 Expanding Clays TERM 29 Where are most of the charges in a 2:1 Expanding clay? DEFINITION 29 In the Octahedral layer TERM 30 List some Smectite clays DEFINITION 30 VermiculiteMontmorilloniteBentonite TERM 31 CEC stands for... DEFINITION 31 Cation Exchange Capacity TERM 32 How do the layers go for a 2:2 clay DEFINITION 32 TOTO TERM 33 What is the origin of sesquioxide clays? DEFINITION 33 Volcanic Ash TERM 34 What is the order of the clays? DEFINITION 34 humusvermiculitesmectities (montmorillonite)illite (mica)chloritekaolinitesesquioxides TERM 35 What are the 3 ways to change the CEC of my soil? DEFINITION 35 1. Add organic matter2. Add clay - vermiculite, bentonite3. Increase the pH TERM 46 -1500 kPa is equal to? DEFINITION 46 permanent wilting point TERM 47 What is CSP? DEFINITION 47 Crop stress point, it is between -1500 and -33 kPa. On the graph it is in the middle but can vary from crop to crop TERM 48 What is PAW? DEFINITION 48 Plant Available Water this is also the -1500 to -33 kPa range TERM 49 Where is the charge in the Vermiculite clay? DEFINITION 49 The Tetrahedral sheet TERM 50 1 kPa = _____ cm DEFINITION 50 10.2 TERM 51 What are the basic cations? (4 of them) DEFINITION 51 K+ potassium, Mg2+ magnesium, Ca2+ calcium, Na+ sodium TERM 52 What are the negative cations? (2) DEFINITION 52 Al3+ AluminumH+ Hydrogen
