duniperus sabina Linnaeus, an evergreen shrub with prostrate life form, can effectively prevent sand moving and is an important tree species for reforestation in semiarid areas of China. It has laterally distributed a...duniperus sabina Linnaeus, an evergreen shrub with prostrate life form, can effectively prevent sand moving and is an important tree species for reforestation in semiarid areas of China. It has laterally distributed adventitious roots and a deeply distributed main root system. To detect water movement between the main root system and adventitious roots, we adopted heat pulse sensors using the Heat Ratio Method, a high precision method for measuring low sap flow rates. Two sensors were implanted in each individual in the stem between the main root system and adventitious roots, and another two in lateral stems distal to all the roots. Positive sap flows during nighttime, even under saturated air moisture conditions, were detected only between the main root system and adventitious roots under drought conditions, and the rate of flow increased as drought progressed and decreased or disappeared after rain events. The results demonstrated the existence of water movement from the main root system to adventitious roots, and combined with the high contribution of nighttime sap flow to transpiration （11%-16%） the results indicate that it also involves the process of hydraulic lift, a water movement from moist subsoil to dry surface soils. Integrated water use strategy between the main root system and adventitious roots via the process of hydraulic lift of soil water maximizes water acquisition efficiency from both subsoil water and water from rain pulses on the soil surface; this increases survivability in the water-limited environment of semiarid areas.展开更多
The Republic of Azerbaijan, is a country in the south Caucasus having continental influenced climate with warm summer and mild cold, dry winters. Relating to its climate this region has a rich and very interesting veg...The Republic of Azerbaijan, is a country in the south Caucasus having continental influenced climate with warm summer and mild cold, dry winters. Relating to its climate this region has a rich and very interesting vegetation cover. In presented article the vegetation communities with the presence of Juniperus communis L. species and subspecies have been described.展开更多
The main objective of the present study was to model the kinetics of essential oil extraction from swelled ground juniper berries by classic hydrodistillation(HD) and microwave-assisted hydrodistillation(MAHD). A new ...The main objective of the present study was to model the kinetics of essential oil extraction from swelled ground juniper berries by classic hydrodistillation(HD) and microwave-assisted hydrodistillation(MAHD). A new phenomenological kinetic model was developed on the basis of the juniper essential oil extraction mechanism that assumed three mass transfer processes occurring simultaneously: washing, unhindered diffusion and hindered diffusion. The new model was compared to the existing kinetic models. Among the tested models,the new model had the smallest mean relative percentage deviation and the highest corrected Akaike information criterion value. In addition, that, the new model was verified for HD and MAHD of essential oils from some other plant materials. On the basis of the above-mentioned facts, the new model can be recommended for modeling the kinetics of essential oil extraction by both HD and MAHD.展开更多
文摘duniperus sabina Linnaeus, an evergreen shrub with prostrate life form, can effectively prevent sand moving and is an important tree species for reforestation in semiarid areas of China. It has laterally distributed adventitious roots and a deeply distributed main root system. To detect water movement between the main root system and adventitious roots, we adopted heat pulse sensors using the Heat Ratio Method, a high precision method for measuring low sap flow rates. Two sensors were implanted in each individual in the stem between the main root system and adventitious roots, and another two in lateral stems distal to all the roots. Positive sap flows during nighttime, even under saturated air moisture conditions, were detected only between the main root system and adventitious roots under drought conditions, and the rate of flow increased as drought progressed and decreased or disappeared after rain events. The results demonstrated the existence of water movement from the main root system to adventitious roots, and combined with the high contribution of nighttime sap flow to transpiration （11%-16%） the results indicate that it also involves the process of hydraulic lift, a water movement from moist subsoil to dry surface soils. Integrated water use strategy between the main root system and adventitious roots via the process of hydraulic lift of soil water maximizes water acquisition efficiency from both subsoil water and water from rain pulses on the soil surface; this increases survivability in the water-limited environment of semiarid areas.
文摘The Republic of Azerbaijan, is a country in the south Caucasus having continental influenced climate with warm summer and mild cold, dry winters. Relating to its climate this region has a rich and very interesting vegetation cover. In presented article the vegetation communities with the presence of Juniperus communis L. species and subspecies have been described.
文摘The main objective of the present study was to model the kinetics of essential oil extraction from swelled ground juniper berries by classic hydrodistillation(HD) and microwave-assisted hydrodistillation(MAHD). A new phenomenological kinetic model was developed on the basis of the juniper essential oil extraction mechanism that assumed three mass transfer processes occurring simultaneously: washing, unhindered diffusion and hindered diffusion. The new model was compared to the existing kinetic models. Among the tested models,the new model had the smallest mean relative percentage deviation and the highest corrected Akaike information criterion value. In addition, that, the new model was verified for HD and MAHD of essential oils from some other plant materials. On the basis of the above-mentioned facts, the new model can be recommended for modeling the kinetics of essential oil extraction by both HD and MAHD.
