| With the increasing of global climate changes, extreme climate events such as uneven seasonal distribution of rainfall, heavy rain event and storm event may become more. The ability of natural precipitation accumulation under agricultural facilities and cultivation measures and its water utilization efficiency was challenged and to be one of the restraining factors in the agricultural production. The paper summarized the recent progress on practice of RT in previous research, and further proposed a new technology-Water-Saving Ridge Tillage&Terrace Cultivation Technology, whose character was drying-wetting infiltrating irrigation, water storage in the ditch and rice seedling planting in the ridge. This technology will show us a new approach to achieve the goals of high yielding, more efficient and ecological on crop production by reducing water consumption and enhance WUE, similarly to the classic farmning technology of China such as rice-fish complex ecosystem and rice-duck complex ecosystem. Consequently, the paper study systemically yield formation mechanism and water movement rule of Ridge Tillage&Terrace Cultivation Technology for providing theoretical basis and technical support of its optimizing and popularization&application. The main results were shown as follow:(1) There was a difference of yield among different planting mode. Compared with conventional flat planting (TO), T1(60cm width of the ridge in the ridge tillage&terrace cultivation technology) and T3(70cm width of the bed in the bed cultivation model) were enhance rice yield, including the highest yield was T1, which increase averagely22.2%(17.1%～27.2%) with T0, next to T3, which increase averagely10.4%(5.8%～15.0%). Further analysis of yield components was shown:compared with T0, the advantage of T1was higher effective panicle per m-2, an average increase of15.4%(9.7%～21.1%), the difference of spikelets per panicle, filling ratio and grain weight was not significance. The advantage of T3(2011year) was mainly reflected in effective panicles and spikelets per panicle, with an average increase of12.4%and3.4%, respectively.(2) There was no difference of quantitative characteristic such as root length, root number among different planting mode, possible reason was the relation of root adjust by itself. Compared with TO, root oxidizing capacity in the full-heading stage under ridge tillage&terraced cultivation increase averagely21.9%, specific surface area and root active absorption was enhance7.2m2cm-3,0.4m2cm-3respectively, and large vessel areas, all vessel areas was bigger than TO, but root cross sectional areas was decline15%-25%with TO. In addition, the epidermal thick cells of root cortex under ridge tillage&terraced cultivation was small and loosely arranged, and the entire thickness of root cortex was less than TO, root vascular cylinder increase25.0%-27.3%.(3) Two year’s experimental results were shown:the advantage of ridge&terraced ecological rice farming (RTERF) and bed ecological rice farming (BERF) mainly reflected in dry matter accumulation after the full-heading stage. No. of spikelets/leaf area, No. of filled grains/leaf area and grain weight/leaf area under RTERF were higher than conventional rice farming (CRF), indicating load-carrying per area spikelets, filled grains and grain weight under RTERF was higher than CRF, the coordinate state between sink and source was good. Meanwhile, there has higher photosynthetic potential in the RTERF, photosynthetic potential before heading in the RTERF was higher55.3%than CRF, but the net assimilation rate in the RTERF was lower21.9%than CRF. Canopy light interception rate in the RTERF was higher5.3%than CRF.(4) Using RTERF,△F/Fm1and rETR value in Yliangyou1hao in the full-heading stage was slightly lower than CRF or flat with CRF, but△F/Fm’and rETR value in15days after full-heading stage significantly higher than CRF. The phenomenon was not observed in the Shanyou63and Huanghuazhan, possible reason was the difference among different varieties. Similarly, with photosynthetically active radiation (PAR) increasing, flag leaf’s NPQ, qP value in the full-heading stage was slightly lower than CRF or flat with CRF, but NPQ, qP value in15days after full-heading stage significantly higher than CRF. Results suggested that the decline trend of leaf photosynthetic physiological activity after full-heading stage was slowdown, self-defensive ability of PS Ⅱ reaction center antenna pigments had not decline, the portion of photochemical electron transfer in the PS Ⅱ antenna pigments absorb light energy and the status of "open" was not significantly alter. Consequently, the structure of the photosynthetic physiological activity remained at a high level.(5) The curve surface of different specification of the ridge was described as a parabolic curve, the opening down.60cm width in the ridge as dividing line, the height of R30, R45, R60was less than20.00cm, and the height of R90, R120was larger than20.00cm, but less than30.00cm. Water storage capacity was increase with the height of the ridge increasing, but there was a difference among different width of the ridge. When the height of the ridge was less than19.00cm, the largest storage capacity was R30, which higher8.77%and11.41%than that of R45, R60, respectively, the next was R45, R60. When the height of the ridge was less than28.00cm, the largest storage capacity was R120, which higher3.30%than that of R90. With the size of the ridge increasing,5cm,15cm (under the top of the ridge) soil moisture decreases, and the distance of water lateral movement increase, which also led to a more homogeneous of soil moisture in the narrow ridge (R30, R45), and quite different soil moisture in the wide ridge (R60, R120). The difference of temperature was small in the different specifications of the ridge,5cm,15cm soil temperature difference was less than0.4℃, and15cm soil temperature (except R60) was higher than that of5cm soil temperature, indicating the trend of heat transfer from top to bottom, and maintained uniformity of the ridge body heat.(6) Theoretical yield of R30, R45, R60was increase48.12%,4.05%and41.25%, respectively, with conventional flat planting (CK), that of R90, R120was decrease12.71%,15.04%, respectively, with CK. Yield components was shown:effective panicle of R30, R45, R60was increase38.71%,22.58%and44.09%, respectively, with CK, but that of R90, R120was less than CK; spikelets per panicle of R30, R60was increase14.41%,2.72%repectively, compared with CK, that of R45was decrease12.37%. From the contribution ratio (CR) of different planting site in the ridge, the CR of different planting site in the R30was0.56:0.44, CR of the up of the ridge was higher12%than that of the down of the ridge. The CR of drfferent planting site in the R45cm was0.37:0.32(CR of the down of the ridge was0.63), but considering planting pattern of R45was one plant in the up of the ridge and two plant in the down of the ridge, CR of the up of the ridge was higher5%than that of the down of the ridge. The CR of different planting site in the R90and R120was0.33:0.34:0.33,0.17:0.29:0.31:0.23, respectively, there has no advantage planting the up of the ridge. Consequently,60cm width ridge was a critical value, greater or less than60cm width ridge, there was different contribution rate of yield in different planting site of the ridge. |
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