| According to the statistics,52.5% of China's total land area is arid and semi arid regions, water shortage on the regional plant growth and productivity caused a lot of negative effects, and even threaten the food security of our country. The development of water saving agriculture and dry land agriculture plays an important role in the development of agriculture in the future. Professor Sun Xihuan at the end of the 20 th century, put forward a new garden water-saving irrigation method, water storage pit irrigation by water storage pit irrigation in the deep three-dimensional, and then improve the soil permeability and induced root deeply rooted, with irrigation, drought resistant, water conservation and anti water stop soil erosion etc. advantages.Root system is the "root" of the crop, it is the main control center of agricultural production measures, and the growth and development of the above ground parts of the crop is affected and regulated by each other. The root system is deeply embedded in the soil, and the changes of the shape and function of the soil environment are different. Soil enzyme is the driving force of soil metabolism, which reflects the nature of the soil biological activity, and the growth and development of the crop root is also affected by each other. Since the water storage pit irrigation method proposed since, in the roots of fruit trees are basic theory research, distribution characteristics. The apple tree root water uptake were studied and established the two-dimensional root length density distribution function. Kuai Bin, finishing the ten year old red Fuji Apple root system density data, the establishment of an improved two-dimensional Mole-Remson model. Hao Fengzhen studied three Dwarfing Rootstocks distribution of the red Fuji Danxia apple tree roots and established the model of water. The above research results have laid a theoretical foundation for the practical application of water storage pit irrigation, but not from the root and soil, the root morphology and vitality of fruit trees and soil enzyme activities were studied. The systematically analysis of the water storage pit irrigation under the condition of different irrigation lower limit on root morphology and activity and soil enzyme activity influence, aims to enrich the water storage pit irrigation of the roots of fruit trees under, lay a theoretical basis for the further development of water storage pit irrigation water-saving irrigation system. Main conclusions:?1? Water storage pit irrigation under the three irrigation treatments of fruiter roots length, area and volume were showed a trend of first increase and then decrease the increase with the depth of soil layers. Among them T1 treatment was the maximum, each index maximum value appeared in the 60-80 cm layer, T2 treatment times, peak soil in 40-60 cm at T3 minimum in 20-40 cm layer reached the highest value. Water storage pit irrigation three irrigation treatments root average diameter in 0-40 cm soil have increased to a certain extent, under the soil gradually decreases, average diameter of roots in different soil layers were T3 treatment, T1 times, T2 treatment is the lowest; Three irrigation treatments of root biomass in the vertical to the space showed first increased and then decreased and the maximum position and the soil root length to a maximum value of soil in the same position, different is, the soil root biomass for T2 treatment, T1 times T3 minimum; Three irrigation treatments root water content rate in the vertical to the soil space showed a trend of increased first and then decreased, in each layer of the T1 treatment was always the largest, and the peak value appeared in the soil 100-120 cm, T2 treatment times, T3 treatment minimum peak soil position to move gradually; Water storage pit irrigation conditions under the three irrigation treatments of root activity in the vertical space for increased first and then decreased trend. The peak soil followed by 80-100 cm, 60-80 cm, 40-60 cm, before birth later period is different, The root activity of D in the 0-40 cm soil layer was greater than that of the three irrigation treatments under the water storage pit irrigation in the 40 cm soil layer, and the T1 treatment and T2 treatment showed obvious advantage. To the maturity of the whole range of T1 treatment is always the largest, T2 processing times, T3 treatment is still the smallest.?2? During the whole growing period of apple tree, the three irrigation treatments all showed increasing trend in the condition of water storage pit irrigation, and the T1 treatment in the whole growth period was the biggest, the T2 treatment was the second, and the T3 treatment was the least; in the whole growth period showed first decreased and then increased trend, the flowering period sampling measured value minimum. The three irrigation treatments T3 treatment value maximum, and T1 times, T2 treatment is the lowest; root biomass in the whole growth period showed a gradually increasing trend, T2 treatment in different growth stage is always the maximum, T1 times, T3 treatment is the lowest; the whole growth period T1 treatment has been the largest, T2 treatment times, T3 is the smallest, and rate of the three irrigation treatments in roots under water with the advance of growth period increased first and then decreased, to expanding period began to decline, but the final root moisture content are greater than the initial value. In terms of time, with the advance of growth stage showed first increased and then decreased trend, greatly improved in young fruit stage, root vigor and in in the growth period of T1 processing to catch up with and surpass the T2 treatment, young fruit period sampling measured values to a slight decrease in the highest and the expanding stage and mature stage decreases rapidly.?3? Water storage pit irrigation, the urease activity of three irrigation treatments increased with the increase of soil depth, and the peak soil layer was 60-80 cm, 40-60 cm and 20-40 cm. The urease activity increased rapidly during the period of expansion, and the activity of urease decreased significantly, and the maturity of fruit trees decreased slightly;Water storage pit irrigation under the condition of the three irrigation treatments of phosphatase activity in the vertical to spatial variation trend for increased at first and then decreased, the soil phosphatase activity and the size relation of the T1>T2>T3;Water storage pit irrigation under the condition of the catalase activity of three irrigation treatments were with the deepening of the soil was decreased first and then increased to the trend, in the 0-100 cm soil layer, T2 treatment, and greater than D treatment, T3 treatment times T1 minimum;With the increase of soil depth, the nitrate reductase activity gradually increased and then decreased gradually.?4? Under the T1 treatment of the soil urease activity in the vertical and the whole growth period, the soil urease activity was the biggest, the T2 treatment times, and was larger than the D treatment, the T3 treatment was the smallest, and was smaller than the D treatment;In the whole growth period of overall trend for first decreases, then increases and finally decreases again, and T1 phosphorus acid enzyme activity remains is the largest, and much larger than D treatment, T2 treatment times, slightly higher than that in treatment D, T3 minimum, and it is always less than D treatment; During the whole growth period, the change of the whole growth period increased and then decreased. And in the root growth region, the catalase activity in T2 treatment was obviously dominant in the whole growth stage; the whole growth period showed the first increase and then decreased, and the mature period tended to be stable. In space and time, T1 processing is always higher than other processing, T2 processing times, and greater than D processing, T3 processing is minimal, and less than D processing.?5? The correlation coefficient of each index and root activity under T2 treatment was the maximum in each growing period,T1 second, and higher than that of D treatment, T3 treatment and D treatment is less than the minimum. The correlation coefficient of each index and root activity with the growth period of the propulsion performance first increased and then decreased trend, in young fruit stage and expanding stage of higher correlation coefficients, root moisture content and the root system vigor of the correlation coefficient in the whole growth period is the highest. In four kinds of soil enzymes, nitrate reductase activity and root activity showed positive correlation, catalase activity was always showed significant negative correlation.?6? In the whole growth period length, root surface area, root water content rate, urease activity and nitrate reductase activity always and root activity had a positive effect on relationship, always a negative effect only catalase activity, and root diameter, root volume and root biomass amount in spring shoots of vigorous long-term, full flower period and fruit stage and root activity had a positive effect on to the enlargement stage and mature stage was negative relationship;T1 treatment and T2 treatment in addition to catalase activity and other indicators were positively correlated with root activity, and T3 treatment of root diameter, root surface area and root biomass and root activity were negatively correlated. The direct path coefficient of root volume and root activity was the largest under T1 treatment, and the maximum surface area under T2 treatment was the largest under T3 treatment.?7? Stepwise regression analysis was carried out to screen and remove the influence factors, so as to establish a more reasonable and accurate fitting equation. According to the experience, the evaluation model is determined, and the membership function and evaluation matrix are determined by the maturity of the semi trapezoidal distribution. With the expanding stage?4060cm depth? calculate the specific evaluation model for the sample, the test sample and calculate the evaluation sample drawing contour map, obtained by comparing the high reliability evaluation model. |
PDF Full Text Request