Phoxim（emulsifiable concentrate（EC） and granules（G）） has been widely used in bamboo forests. The persistence and magnitude of phoxim residues in the crop and soil must be investigated to ensure human and environ...Phoxim（emulsifiable concentrate（EC） and granules（G）） has been widely used in bamboo forests. The persistence and magnitude of phoxim residues in the crop and soil must be investigated to ensure human and environmental safety. The environmental behaviors of the two formulations were investigated in a bamboo forest under soil surface mulching conditions（CP） and non-covered cultivation conditions（NCP）. The half-lives of phoxim in soil under the two conditions in soil were 4.1–6.2 days（EC） and 31.5–49.5 days（G）,respectively. Phoxim in EC could be leached from the topsoil into the subsoil. A minimized leaching effect was observed for G under NCP. Inversely, an enhanced leaching effect was observed for G under CP. The G formulation resulted in more parent compound（in bamboo shoots） and metabolite（in soil） residues of phoxim than in the case of EC, especially under CP conditions. In addition, the intensity and duration of the formulation effect on soil p H adjustment from G were more obvious than that from EC. Results showed that the environmental behaviors（distribution, degradation, residue） of phoxim in the bamboo forest were significantly influenced by the type of formulation. The prolongation effect from phoxim G might cause persistence and long-term environmental risk. However,bamboo shoot consumption could be considered relatively safe after applying the recommended dose of the two phoxim formulations.展开更多
Soil evaporation(SE)is a key component of regional hydrological balance,especially in arid areas.China has the largest area of apple orchards in the world,but the effects of mulching practices on sE dynamics and their...Soil evaporation(SE)is a key component of regional hydrological balance,especially in arid areas.China has the largest area of apple orchards in the world,but the effects of mulching practices on sE dynamics and their controlling factors remain poorly understood in orchards using drip irrigation(DI).This study was conducted to address these issues by measuring SE,meteorological factors,soil temperature(ST),and soil water content(SwC)in young apple orchard under two mulching treatments during the growing season.Field experiments,which included three treatmentsfilm mulching(FM)and maize straw mulching(SM),and clean tillage(TL)asa comparatorwere conducted in 3-year-old apple orchard with Dl in arid northwestern China.The results revealed that mulching significantly affected the daily SE dynamics of the young orchard(p<0.05),and the daily mean SE under FM,SM,and TL treatments was about 1.3±0.5,1.3±0.4,and 1.7±0.4 mm·d^(-1),respectively.No significant differences were detected in the daily SE between FM and SM treatments(p>0.05),whereas the daily SWC in the four soil layers to 120 cm were consistently greater under SM treatment than under FM and TL treatments(p<0.05).Compared to the TL treatment,the daily SE under FM and SM treatments was more susceptible to meteorological factors.Stepwise regression analysis showed that the daily SE of the young orchard was mainly controlled by the vapor pressure deficit,reference evapotranspiration and solar radiation,regardless of the treatment.However,there was no significant relationship between the daily SE and wind speed under TL treatment(p>0.05).This study highlighted the significant differences in SE losses and SWC dynamics of the mulching treatments.Overall,SM is considered to be a more effective mulching practice for reducing unproductive SE and improving SWC status in young apple orchards with DI in arid and similarclimatic regions.展开更多
基金financial support from the Applied Research Project in the Public Interest of Zhejiang Province (Nos: 2013C32106, 2015C32071)the Fundamental Research Funds for the Central Non-profit Research Institution of CAF (No. RISF61252)the Special Fund for Forestry Scientific Research in the Public Interest (No. 201304705)
文摘Phoxim（emulsifiable concentrate（EC） and granules（G）） has been widely used in bamboo forests. The persistence and magnitude of phoxim residues in the crop and soil must be investigated to ensure human and environmental safety. The environmental behaviors of the two formulations were investigated in a bamboo forest under soil surface mulching conditions（CP） and non-covered cultivation conditions（NCP）. The half-lives of phoxim in soil under the two conditions in soil were 4.1–6.2 days（EC） and 31.5–49.5 days（G）,respectively. Phoxim in EC could be leached from the topsoil into the subsoil. A minimized leaching effect was observed for G under NCP. Inversely, an enhanced leaching effect was observed for G under CP. The G formulation resulted in more parent compound（in bamboo shoots） and metabolite（in soil） residues of phoxim than in the case of EC, especially under CP conditions. In addition, the intensity and duration of the formulation effect on soil p H adjustment from G were more obvious than that from EC. Results showed that the environmental behaviors（distribution, degradation, residue） of phoxim in the bamboo forest were significantly influenced by the type of formulation. The prolongation effect from phoxim G might cause persistence and long-term environmental risk. However,bamboo shoot consumption could be considered relatively safe after applying the recommended dose of the two phoxim formulations.
基金supported by the National Key Research and Development Program of China(2022YFD1900502)the National Field Scientific Observation and Research Station on Efficient Water Use of Oasis Agriculture in Wuwei of Gansu Province(KF2021004)。
文摘Soil evaporation(SE)is a key component of regional hydrological balance,especially in arid areas.China has the largest area of apple orchards in the world,but the effects of mulching practices on sE dynamics and their controlling factors remain poorly understood in orchards using drip irrigation(DI).This study was conducted to address these issues by measuring SE,meteorological factors,soil temperature(ST),and soil water content(SwC)in young apple orchard under two mulching treatments during the growing season.Field experiments,which included three treatmentsfilm mulching(FM)and maize straw mulching(SM),and clean tillage(TL)asa comparatorwere conducted in 3-year-old apple orchard with Dl in arid northwestern China.The results revealed that mulching significantly affected the daily SE dynamics of the young orchard(p<0.05),and the daily mean SE under FM,SM,and TL treatments was about 1.3±0.5,1.3±0.4,and 1.7±0.4 mm·d^(-1),respectively.No significant differences were detected in the daily SE between FM and SM treatments(p>0.05),whereas the daily SWC in the four soil layers to 120 cm were consistently greater under SM treatment than under FM and TL treatments(p<0.05).Compared to the TL treatment,the daily SE under FM and SM treatments was more susceptible to meteorological factors.Stepwise regression analysis showed that the daily SE of the young orchard was mainly controlled by the vapor pressure deficit,reference evapotranspiration and solar radiation,regardless of the treatment.However,there was no significant relationship between the daily SE and wind speed under TL treatment(p>0.05).This study highlighted the significant differences in SE losses and SWC dynamics of the mulching treatments.Overall,SM is considered to be a more effective mulching practice for reducing unproductive SE and improving SWC status in young apple orchards with DI in arid and similarclimatic regions.
