| Soil moisture dynamic differences exist in different micro-domain root zones becauseof the application of local irrigation technology and the crop root zone soil physicalparameter and the heterogeneity of the root water uptake, which makes it difficult toevaluate the effectiveness of soil moisture on crop yield. So there are important scientificsignificances and practical values to study the regulation of the root zone soil moisturespatial dynamics and the impact of different micro-domains moisture content changing oncrop physiology growth and root system, which can provide the theoretical basis for thedynamic evaluation of crop validity and soil moisture space regulation.According to the greenhouse micro-region and soil column test, this paper studies thedynamic change regulation of corns root zone soil moisture and the relationship betweenroot zone soil moisture and physiology growth under the condition of horizontal andvertical space water supply, and evaluates the reserves and storage space of valid soil waterin different irrigation treatments and different time. This paper also analyzes the regulationof different moisture in different micro-domains soil affecting partial root growth by thequantitative relationship of the root zone soil moisture and crop growth. As a result, thispaper obtains the identification validity method and the system indicators whendetermining the micro-space of soil moisture content in crop water deficit root zone, andderives the appropriate space and the range of water supply in maize different growthperiod. The main conclusions are shown as follows:(1)The result of greenhouse micro-region experiment: the soil moisture of corn wetand dry root zone always rise and fall in asynchronous alternating. The soil moisture oflevels at0-80cm is approximately distributed as "inverted L-type" in the vertical direction,the changing of the soil moisture of levels at0-30cm is the most heavily, especially in theirrigation side; the soil moisture of levels at30-60cm shows the trend of increasing andthen decreasing with the soil depth increasing, the consumption rate of soil moisture is thesecond to the0-30cm; the soil moisture of the levels below60cm has tiny fluctuations and stable basically, but the hysteresis is obvious with the soil moisture content changing alongwith irrigation as the prolonged time in Water treatment.(2) Plant height and leaf area of corns gradually increase to the constant with theincreasing of water control lower limitation in the form of APRI(Alternate PartialRoot-zone Irrigation),and the stem diameter firstly increases and then decreases gradually.The root-shoot ratio of T4root is the highest for adopting low-water and the root-shootratio of T3root is the lowest for adopting mid-water.The overall trend of dry matter weightalso shows a manner of T1> T2> T3> T4. The alternate partial root-zone irrigation willaffect the adjustment and distribution of proportion of every organ, there is no significantdifference in the processing of T1and T2above the ground under the condition of noinfluence on the root growth with the processing of T2. Meanwhile,the root activity slowsdown due to the soil drought under the condition of the lowing of soil moisture lower limitin the different growth period.(3) In the APRI model, with the increase of the lower limit, the soil moisture variationin the dry root district decreases gradually, and the low water treatment of the dry side hasthe greatest changes. The percentage of the water aborted by corn root in dry side by thewhole also increases with the soil water content in dry side increased. Soil moisture has asignificant positive correlation with Tr,Pn, Gs, CC, CSC.They reduced with the watercontrol of the lower limit increased, and the T2treatment is significantly greater than theT1treatment. The Pn and Gs of APRI has a big difference from the conventional irrigation.(4) In the soil column test, the trend of plant height of different irrigation model showsT4>T3>T2>T1; the change trend of leaf area and stem diameter is the same with the APRI.In the T1treatment, the increasing of the upper layer soil water consumption makes theroot system distribution in the upper layer increasing relatively, and the dry mass increasesignificantly. In the T2treatment, the drought of the upper layer and the middle layerroot zone makes the dry mass of the root system in the middle layer increasing,but thepercentage of the root weight by the whole plant dry mass has been decreased. In the T3treatment, the corn root system and the whole plant dry mass increase relatively byincreasing the lower layer soil water supply, so it is helpful for the plant growth with thedrought of the upper and middle layers in the T3treatment. Different wet ways for cornhave a significant effect on root activity.(5) Soil column test results show that: the root system main absorbes water by rootzone in irrigation side, but the water content of root zone in the no irrigation area is still ina considerable proportion, the consumption in upper layer root zone soil water of the upper irrigation T1treatment is the largest, the middle layer irrigation T2treatment is larger thanlower layer irrigation T3treatment. The soil water consumption of the middle layer and thelower layer reduces in turn, which is both lower than the soil water consumption of theupper layer; the upper layer root zone of T2treatment is influenced by the soil evaporation,the soil water consumption is the second to the middle and larger than the lower layer rootzone；the soil water consumption of the lower root zone is the largest, but there is nosignificant differences with the upper layer root zone, the soil water consumption of themiddle layer root zone is the lowest.(6) Within a certain range, the production of the corn is increased with the increasingof water consumption. The yield of T2treatment and T3treatment was significantly betterthan T4, and there is no obvious differences with the T1treatment. The WUE in general T3are greater than other treatment. |
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