SCHRIFTENREIHE Institut für Pflanzenernährung und Bodenkunde ...

Recommendations

Info

UG 79 is assumed to be the result of a sandier parent material. However, the coarse-textured topsoil in HG might be partly attributed to erosion of fine particles by wind from the predominantly bare gro<strong>und</strong>. In the topsoil, bulk density increases with increasing grazing intensity, indicating the effects of mechanical stresses on soil structure induced by animal trampling. At the ungrazed sites, bulk density is much higher in the second soil layer compared to the topsoil. This is a sign that the upper soil layer has obviously recovered from previous sheep trampling. Compared to the other three sites, the total C-content (4-8 cm) in HG is reduced by about 50%, which may be due to both wind erosion of particulate organic matter and higher mineralization rates. 94 Table 5.2. Soil texture, bulk density and organic carbon content of the four sites. Site Soil depth Sand Silt Clay Bulk density Organic carbon (cm) (%) (%) (%) (g cm -3 ) (g kg -1 ) UG 79 4-8 59.0 27.5 13.5 1.14 22.0 18-22 66.1 21.2 12.7 1.39 16.5 30-34 75.3 14.6 10.2 1.42 10.1 40-44 78.2 12.5 9.3 1.40 8. 2 UG 99 4-8 52.5 31.0 16.5 1.11 19.6 18-22 59.1 26.9 14.0 1.33 23.1 30-34 54.8 29.9 15.3 1.34 15.9 40-44 56.5 28.1 15.4 1.27 15.0 WG 4-8 49.8 32.2 18.0 1.28 22.2 18-22 54.9 28.0 17.1 1.29 13.2 30-34 54.7 29.7 16.6 1.24 11.4 40-44 54.9 27.9 17.3 1.25 11.6 HG 4-8 65.8 21.6 12.6 1.30 11.8 18-22 73.2 16.0 10.7 1.42 7. 2 30-34 71.3 17.2 11.6 1.43 6. 5 40-44 72.8 16.6 10.6 1.45 6. 0 Water Retention Characteristics and Hydraulic Conductivity Total pore volume generally decreases from the topsoil layer to the subsoil for all sites (Fig. 1). In the topsoil, the total and large pore (>50 μm) volumes significantly decrease with increasing grazing intensity. Especially, HG shows a
Chapter 5 Modeling Grazing Effects on Coupled Water and Heat Fluxes in Inner Mongolia Grassland clear reduction in the fraction of large pores which is accompanied by an increasing fraction of medium pore sizes (0.2-50 μm), indicating strong soil compaction effects due to animal trampling. Note that owing to the coarse-textured soil in HG, the fraction of larger pores should be higher than that in the other fine-textured sites. Moreover, the volume fraction of fine pores (50 μm), pF
Page 1 and 2:
SCHRIFTENREIHE Institut für Pflanz
Page 3 and 4:
Aus dem Institut für Pflanzenernä
Page 5:
I Table of contents I Table of cont
Page 8 and 9:
controlling soil moisture are of pa
Page 11 and 12:
Zusammenfassung Überweidung wird a
Page 13 and 14:
Die Beweidung beieinflusst besonder
Page 15 and 16:
II List of figures Fig. 2.1. Locati
Page 17 and 18:
measured soil moisture in time stab
Page 19 and 20:
III List of tables Table 2.1. Descr
Page 21 and 22:
1.1 Background Chapter 1 Introducti
Page 23 and 24:
Chapter 1 Introduction is also unce
Page 25 and 26:
Chapter 1 Introduction water in spr
Page 27 and 28:
Chapter 1 Introduction requires the
Page 29 and 30:
Chapter 1 Introduction Krümmelbein
Page 31 and 32:
Chapter 2 Spatial variability of so
Page 33 and 34:
Page 35 and 36:
Page 37 and 38:
Page 39 and 40:
Page 41 and 42:
Page 43 and 44:
Page 45 and 46:
Page 47 and 48:
Page 49 and 50:
Page 51 and 52:
Page 53 and 54:
Page 55 and 56:
Page 57 and 58:
Page 59 and 60:
Chapter 3 Spatio-temporal variabili
Page 61 and 62:
Chapter 3 Spatio-temporal variabili
Page 63 and 64: Chapter 3 Spatio-temporal variabili
Page 73 and 74: Chapter 3 Factors controlling spati
Page 85 and 86: Chapter 4 Temporal stability of soi
Page 89 and 90: Y orientation Chapter 4 Temporal st
Page 93 and 94: MRD(%) MRD(%) 100 80 60 40 20 0 -20
Page 101 and 102: Soil water content (%) 40 30 20 10
Page 105 and 106: Chapter 5 Modeling Grazing Effects
Page 113: Chapter 5 Modeling Grazing Effects
Page 135 and 136: Chapter 6 Modeling of Coupled Water
Page 159 and 160: Chapter 7 General discussion and co
Page 165 and 166:
Chapter 7 General discussion and co
Page 167 and 168:
References Chapter 7 General discus
Page 169 and 170:
Chapter 7 General discussion and co
Page 171 and 172:
8. ACKNOWLEDGMENTS Firstly I would
Page 173 and 174:
Curriculum Vitae M.Sc. Ying Zhao Of
Page 175:
Schriftenreihe des Instituts Neuere
show all

SCHRIFTENREIHE Institut für Pflanzenernährung und Bodenkunde ...

Create successful ePaper yourself

Delete template?

Save as template?