World’s Soil Resources

14.5.4 | Nutrient imbalance | 464
14.6 | Conclusions and recommendations | 467
15 | Regional Assessment of Soil Change in the Southwest Pacific | 476
15.1 | Introduction | 477
15.2 | The major land types in the region | 477
15.3 | Climate | 480
15.4 | Land use | 480
15.4.1 | Historical context | 480
15.4.2 | Nineteenth and twentieth centuries | 481
15.4.3 | Contemporary land-use dynamics | 482
15.5 | Threats to soils in the region | 485
15.5.1 | Erosion by wind and water | 485
15.5.2 | Soil organic carbon change | 487
15.5.1 | Soil contamination | 490
15.5.2 | Soil acidification | 492
15.5.3 | Salinization and sodification | 494
15.5.4 | Loss of soil biodiversity | 495
15.5.5 | Waterlogging | 496
15.5.6 | Nutrient imbalance | 496
15.5.7 | Compaction | 497
15.5.8 | Sealing and capping | 498
15.6 | Case studies | 498
15.6.1 | Case study one: Intensification of land use in New Zealand | 498
15.6.3 | Case study two: Soil management challenges in southwest Western
Australia | 500
15.6.2 | Case study three: Atoll Islands in the Pacific | 504
15.6.4 | Case study four: DustWatch – an integrated response to wind erosion in
Status of the World’s Soil Resources | Main Report
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