000			01935nam a2200229#a 4500
001			vtls000013956
008			230822s1989 xx 000 0 eng d
020			_a9251028796
040			_aJPS
090	0	0	_aFAO-PAPER 45
100			_aWalker, W.R. _eauthor
245		0	_aGuidelines for designing and evaluating surface irrigation systems / W.R.Walker
260			_aRome: FAO., _c1989
300			_a137p; illust. 30cm
440			_aFAO Irrigation and Drainage Paper no; 45
505			_a1. The practice of irrigation. 1.1 The perspective and objectives of irrigation. 1.2 Irrigation methods and their selection. 1.3 Advantages and disadvantages of surface irrigation. 2. Surface irrigation systems. 2.1 Introduction to surface irrigation. 2.2 Surface irrigation methods. 2.3 Requirements for optimal performance 2.4 Surface irrigation structures. 3. Field measurements 3.1 Field topography and configuration. 3.2 Determining water requirements 3.3 Infiltration. 3.4 Flow measurements. 3.5 Field evaluation. 4. Evaluation of field data. 4.1 Objectives of evaluation. 4.2 Performance measures. 4.3 Intermediate analysis of field data. 4.4 Systems evaluation. 4.5 General alternatives for Improvement 4.6 An example furrow irrigation evaluation 5. Surface irrigation design. 5.1 Objectives and scope of design 5.2 The basic design process. 5.3 Computation of advances and intake opportunity time. 5.4 Furrow irrigation flow rates cutoff times and field layouts. 5.5 Border irrigation design. 5.6 Basin irrigation design. 5.7 Summary. 6. Land levelling 6.1 The importance of land preparations 6.2 Small-scale land levelling 6.3 Traditional engineering approach. 6.4 Laser land levelling 7. Future developments 7.1 Background. 7.2 Surge flow. 7.3 Cablegation 7.4 Adaptive controls systems 7.5 Water supply management.
546			_aeng
650	1	0	_aSurface irrigation.
942			_cMONO
990			_a1989
999			_aVIRTUA00 _c10009 _d10009
003			JPS