Rehabilitation of degraded sodic lands during a decade of Dalbergia sissoo plantation in Sultanpur District of Uttar Pradesh,India

The ameliorative effect of Dalbergia sissoo, planted on sodic land at Sultanpur (26° 10′–26° 40′N, 81° 45′–82° 30′E), India, in a tropical environment, was studied at 3, 6 and 9 years of age. The soil properties of the sites improved significantly, showing marked reduction in pH, electrical conductivity (EC) and exchangeable sodium percentage (ESP) and an increase in organic carbon, nitrogen and availability of nutrients in the soil. The significant reduction in Na ion was found in all the age groups. Results showed an improvement in the soil moisture regime due to increased infiltration rate (cm hr⁻¹), soil permeability (cm²), water‐holding capacity, field capacity and pore space whereas, the bulk density decreased significantly after successive years of planting. The effect on soil attributes was confined to surface soil in the young plantation and deeper in older plantation. Therefore, the study clearly indicated that the sodic soil could be desodified by growing D. sissoo plantations on these degraded sites. Copyright © 2002 John Wiley & Sons, Ltd.     

Bioreclamation of sodic waste land—a case study

The study reports a case of bioreclamation of a once barren sodic landscape in the middle part of Gangetic alluvial plain at Banthra Research Station (National Botanical Research Institute, Lucknow, India) (80° 45′ – 53′E and 26° 40′ – 45′N) which began about four decades ago. The investigations were carried out to ascertain the changes in soil characteristics caused by different land‐use systems adopted consistently over three decades. The results showed that the anthropogenic effect on alteration of surface texture through addition of sand in soils of Typic Natrustalfs is still distinct but persistent sodicity is retained. The soils of Inceptic Haplustalfs are markedly improved showing pH value around 8 and ESP > 4 with negligible CaCO₃. The soils of Aeric Endoaquepts supporting stands of forest trees are now devoid of sodicity to about 0\5 m depth, whereas the soils of Aeric Halaquepts though under cultivation have mild sodicity. Soils of Typic Halaquepts occurring on a low physiographic position with aquic soil moisture regime have high sodicity. Summarizing the results of changes in the surface (0 – 15 cm) soil characteristics caused by continuous cultivation irrespective of any crop grown on any soil type reveals that there is perceptible reduction in soil pH and ESP after three decades of reclamation using organic amendments coupled with regular cultivation and afforestation in different locations. Copyright © 2000 John Wiley & Sons, Ltd.