Effect Of Shoots Windbreak On Vineyard Ecotope In Soil-buried Cold-proof Period

Ninety percent of Chinese viticulture regions distribute in soil-burying over-wintering zones. Specifically, such kind of viticulture management make the soil surface exposed as long as six months in a year. During the cold winter and the dry windy spring, the exposed soil of large mounding areas results in increasing risks of wind erosion in viticulture regions. Soil wind erosion not only leads to soil drifting, but also causes sand storm which further causes environmental pollution. Winter pruning and soil-bury of grape needed much labor force completed in a short time,which was in contradiction to the rapidly declined country labor force now.With high-speed development of grape and wine industry and expansion of viticultural region, there is in urgent need of improving ecological environment of vineyard during soil-bury over-wintering period and reducing high intensity of labor force. This paper proposes a measure of crawled cordon training planting model. In this measure, the shoots of vines were hung on the wires after winter pruning and forming a kind of windbreak, which played a protective function as shelterbelt network. The work studied the effect on sand arresting effect in ecological environment and the probable influence on grape of the measure. Under this test conditions, the main studying contents and results were concluded as follows:1. Grapevine shoots windbreak pertained to agricultural protection forest of conservation tillage. The degree of porosity of shoots windbreak obeyed normal distribution and its mean was 0.58. It was considered as a ventilating structure.The change of airflow passing by grape shoots windbreak successively was weakening for meeting resistance, accelerating for afflux, weakening rapidly, recovering and reducing at leeward side. Grapevine shoots windbreak decreased the wind speed at the greatest extent at 34 m far away from the edge of windward and its efficiency of prevention was up to 80.72%. The distance from the edge of windbreak at leeward side to 34 m far away from the windbreak belonged to relative effective protection distance, of which average protection efficiency was 40.94%. Different protection length had significantly different protection efficiency.The wind profile could indicate the features of wind speed changing over height. The law curve with wind profile followed power function. At the edge of windbreak at leeward side to 34 m far away from the windbreak, the changing between wind speed and height were lower than other observing positions.Aerodynamics surface roughness(Z0) and friction speed(U*) at different positions in the vineyard ranked as: in the windbreak > the leeward side of windbreak > windward. At 10 m far away from the edge of windbreak leeward side, Z0 reached up to 18.71 cm, and Z0 reached the minimum in the experiment at the edge of leeward side, 5.97cm; U* up to 1.46 m/s at 24 m far away from the edge of leeward side. U* has the minimum in the experiment at 48 m far away from the edge of windward side, 0.60 m/s.2. Grapevine shoots windbreak had sand arresting effect. Sediment discharge of soil wind erosion followed power function with the change of height and all focused on near-surface of 5-40 cm in vineyard when soil was bare during soil-bury over-wintering period. The shoots windbreak influenced significantly sediment discharge distribution near the earth surface. But sediment discharge of vineyard with shoots windbreak tended to be in accordance with that without shoots windbreak as height increased. Sediment discharge on near-surface of 5-150 cm of vineyard with shoots windbreak was 36.02% higher than the control. Rainfall caused total sediment discharge reduced. There was fewer differences between sediment discharge of the vineyard in winter and in spring at the same height in the year with rainfall.Silty sand occupied the maximum ratio of aeolian deposit in mechanical composition. Aeolian deposit at the same height of different grain diameters had significant differences. Aeolian deposit at different heights of the same grain diameter had no significant differences.Wind-induced movement of dust particles was effectively reduced by grape shoots windbreak, up to 75.85%. Soil wind erosion amount at different positions had significant differences. The grape shoots windbreak had huge influence on whether the presentation of vineyard soil wind erosion was deflation or deposition, almost it was deposition. Soil wind erosion amount and presentation were different for different rainfall.3. Grapevine shoots windbreak did not have significant influence on temperature of vineyard after burying. However, the shoots windbreak kept warm on air temperature to some extent. Vineyard with shoots windbreak could increase temperature about 1.1℃ when the temperature reached-19.27℃. The whole temperature of vineyard with shoots windbreak was higher than that of the control at 8:30 and 14:00.Grapevine shoots windbreak had significant influence on the change of relative air humidity in the soil-buried cold-proof period. Changes of relative air humidity in the winter and spring in the vineyard with shoots windbreak and the control tended to be the same. Mean of relative air humidity of the whole observed points in vineyard with windbreak was 2.16% higher than the control at 8:30, 8.86% higher at 14:00 and was lower at 18:00.No matter with or without windbreak, changes of soil temperature at different layers in the vineyard tended to be the same, and no significant between them. There was the lowest temperature at the earth surface 5cm at 8:30 and the soil temperature ascended as the depth of soil increased. The earth surface 5cm had the highest temperature at 14:00, and the soil temperature decreased as the depth of soil increased. Soil water content of 40cm-depth soil layer was higher than that of 20cm-depth soil layer. The change of soil water content at 20cm-depth soil layer in the vineyard with windbreak was more smooth than that of control.Grapevine shoots windbreak had effect of water retention on soil to some extent. Soil water content of different soil layers in vineyard with windbreak was higher than those of control when there was rainfall, about 1.99%. Amplitude of variation of soil water content mean at different soil layers was lower than that of control.4. In the vineyard with shoots windbreak, water content of grape shoots was higher than control, but there was no significant influence between them. Shoots windbreak did not have significant influence on grape germination rate, the morbidity of leafhopper and grapevine erinose. But the morbidity of shoots windbreak were lower than control, about 1.11% for leafhopper, about 0.24% for grapevine erinose.