土壤管理方式对伏旱期柑橘生长及土壤温度和水分的影响

Effects of different soil managements on soil temperature, moisture and citrus growth during summer drought season

【目的】研究伏旱期柑橘园不同土壤管理方式对土壤温度、水分和柑橘Citrus reticulata生长的影响。【方法】试验地点位于重庆北碚,以资阳香橙砧沃柑为材料,2016和2017年高温伏旱期采用清耕(对照)、铲草覆盖、化学杀草覆盖和自然生草4种土壤管理方式,测定地表(0 cm)以及10、20和30 cm土层温度变化,测定0～10、10～20和20～30 cm土层含水量、地表最大开裂宽度、柑橘根系活力和秋梢生长量,统计不同土壤管理成本。【结果】土层越浅土壤温度和水分的波动越大。总体上,不同土壤管理条件下各土层日平均温度、最高温度和温度日较差为清耕>化学杀草覆盖>铲草覆盖>自然生草;在极端高温天气(气温41℃)时,清耕、化学杀草覆盖、铲草覆盖和自然生草的土表最高温度分别为69.6、45.6、37.5和35.0℃。各土层含水量以自然生草和铲草覆盖最高,清耕最低,清耕0～10 cm土层含水量显著低于其他处理。柑橘根系活力和秋梢生长量均为铲草覆盖>化学杀草覆盖>清耕>自然生草。土壤管理成本为清耕>自然生草>铲草覆盖>化学杀草覆盖。【结论】综合效果、成本与简便省力,在高温伏旱期,平地和缓坡橘园宜采用铲草覆盖。

【Objective】To study the influences of different soil management methods on soil temperature, soil moisture and Citrus reticulata growth in citrus orchard during summer drought season.【Method】The experiment was carried out in Beibei, Chongqing using Ziyangxiangcheng (Citrus junos Sieb. ex Tanaka) Zhenwogan (Citrus reticulata cv. Orah) as the material. Four soil management systems, including rotary tillage weeding (CK), mechanical weeding mulch (MWM), chemical weeding mulch (CWM) and weed living mulch (WLM), were used during the summer drought seasons of 2016 and 2017. We measured the temperature at soil layers of 0 (surface),10, 20 and 30 cm depth, the moisture at 0?10, 10?20 and 20?30 cm soil layers, the maximum crack width of surface, citrus root activity and autumn shoot growth, and summarized the costs of different soil management systems.【Result】The shallower the soil layer, the greater the fluctuation of soil temperature and water content. In general, the daily average temperature, maximum temperature and daily temperature range of each soil layer under different soil managements were CK > CWM > MWM > WLM. Under extreme high temperature weather (air temperature 41 ℃), the highest soil surface temperatures of CK , CWM , MWM and WLM were 69.6, 45.6, 37.5 and 35.0 ℃, respectively. The water contents of different soil layers were the highest in WLM and MWM, and the lowest in CK. The water content in 0?10 cm soil layer of CK was significantly lower than those of other treatments. For both citrus root activity and autumn shoot growth, the results were MWM > CWM > CK > WLM. The costs of different soil management systems were in order of CK > WLM > MWM > CWM.【Conclusion】Considering the effect, cost and operability, the flat or gentle slope citrus orchard should be practiced with MWM soil management during summer drought season.