Figure 7
Principal component analysis (PCA) of assayed variables for studying the effect of tillage, crop residue management and green manure after five years of rice–wheat cropping system. PTRW0-puddled transplanted rice with no wheat straw, PTRW25-puddled transplanted rice with 25% anchored wheat straw retained, GM-Green manure, CTWR0-conventional tillage wheat with rice straw removed, ZTWR0-zero tillage wheat with rice straw removed, ZTWR100-ZTW with rice straw retained as surface mulch.. (Acronyms: WS-P Water soluble phosphorus, TP Total phosphorus, Av-P Available phosphorus, Alk-P Alkaline phosphatase).
