Tillage practices during the fallow period benefit water storage and yield in dryland wheat crops.However,there is currently no clarity on the responses of soil organic carbon(SOC),total nitrogen(TN),and available nut...Tillage practices during the fallow period benefit water storage and yield in dryland wheat crops.However,there is currently no clarity on the responses of soil organic carbon(SOC),total nitrogen(TN),and available nutrients to tillage practices within the growing season.This study evaluated the effects of three tillage practices(NT,no tillage;SS,subsoil tillage;DT,deep tillage)over five years on soil physicochemical properties.Soil samples at harvest stage from the fifth year were analyzed to determine the soil aggregate and aggregate-associated C and N fractions.The results indicated that SS and DT improved grain yield,straw biomass and straw carbon return of wheat compared with NT.In contrast to DT and NT,SS favored SOC and TN concentrations and stocks by increasing the soil organic carbon sequestration rate(SOCSR)and soil nitrogen sequestration rate(TNSR)in the 0-40 cm layer.Higher SOC levels under SS and NT were associated with greater aggregate-associated C fractions,while TN was positively associated with soluble organic nitrogen(SON).Compared with DT,the NT and SS treatments improved soil available nutrients in the 0-20 cm layer.These findings suggest that SS is an excellent practice for increasing soil carbon,nitrogen and nutrient availability in dryland wheat fields in North China.展开更多
Limited water resources often result in reduced crop yield and low water productivity（WP）. In northwestern China, crop production is generally dependent on precipitation. Therefore, a variety of agricultural rainwat...Limited water resources often result in reduced crop yield and low water productivity（WP）. In northwestern China, crop production is generally dependent on precipitation. Therefore, a variety of agricultural rainwater harvesting（ARH） techniques have been used for conserving soil moisture, ameliorating soil environment, increasing crop yield, and improving water use efficiency. A two-year（2013–2015） field experiment was conducted under a typical sub-humid drought-prone climate in Yangling（108°24′E, 34°20′N; 521 m a.s.l.）, Shaanxi Province, China, to explore the effects of mulching（same for summer maize and winter wheat） on soil moisture, soil temperature, crop water consumption, and crop yield with a winter wheat/summer maize rotation. Crops were planted in a ridge-furrow pattern and the treatments consisted of a transparent film mulch over the ridges（M1）, a crop straw mulch in the furrows（M2）, a transparent film mulch over the ridges and a crop straw mulch in the furrows（M3）, a black film mulch over the ridges and a crop straw mulch in the furrows（M4）, and a control with no mulch（CK）. Results showed that M4 was the best treatment for improving soil water storage and content, and decreasing crop water consumption during the summer maize and winter wheat rotation. In both maize and wheat seasons, M1 had a higher soil temperature than M2 and CK, and M3 had a higher soil temperature than M4. In the maize seasons, M4 had the highest yield, WP, and precipitation productivity（PP）, with the average values for these parameters increasing by 30.9%, 39.0%, and 31.0%, respectively, compared to those in CK. In the wheat seasons, however, M3 had the highest yield, WP, and PP, with the average values for these parameters being 23.7%, 26.7%, and 23.8% higher, respectively, than those in CK. Annual yield（maize and wheat yields combined） and WP did not differ significantly between M3 and M4. These results suggested that M3 and M4 may thus be the optimal ARH practices for the production of winter wheat and summer maize, respectively, in arid and semi-arid areas.展开更多
In order to explore the spatial variability of soil moisture near the interface of high/low stands, an experiment was conducted at Luancheng Experimental Station, Chinese Academy of Sciences, Hebei, China from May to ...In order to explore the spatial variability of soil moisture near the interface of high/low stands, an experiment was conducted at Luancheng Experimental Station, Chinese Academy of Sciences, Hebei, China from May to June, 1996. By analyzing the observed soil moisture data, it shows that there exists an obvious turning point of soil moisture pattern from one side of the interface to another. The effect of drier soil closer to the interface in winter wheat field is obvious, which is mainly due to the better ventilation condition near the interface in winter wheat filed than in alfalfa field. The irrigation in large scale is one of the most important factors to control the spatial pattern of soil moisture while the small scale human disturbing activity, such as the stealing event occurred during our observation, does not change the spatial pattern of soil moisture obviously. Latent heat, calculated by Bowen ratio method based on our observed micrometeorological data, is shown larger in alfalfa than that in winter wheat both at earring stage from May 8 to 10 and mature stage from June 11 to 14. This fact, together with the larger ground temperature and a little bit larger wind velocity in lower layer, explains that the soil is drier in alfalfa than in winter wheat from May 8 to 10. While for the period from June 11 to 14, irrigation's effect changes the natural interrelationship of soil moisture with meteorology and ground temperature.展开更多
As a conventional farming practice, tillage has lasted for thousands of years in Loess Plateau, China. Although recent studies show that tillage is a prominent culprit to soil carbon loss in croplands, few studies hav...As a conventional farming practice, tillage has lasted for thousands of years in Loess Plateau, China. Although recent studies show that tillage is a prominent culprit to soil carbon loss in croplands, few studies have investigated the influences of tillage on the responses of soil CO2 efflux （SCE） to soil temperature and moisture. Using a multi-channel automated CO2 efflux chamber system, we measured SCE in situ continuously before and after the conventional tillage in a rain fed wheat field of Loess Plateau, China. The changes in soil temperature and moisture sensitivities of SCE, denoted by the Q10 value and linear regression slope respectively, were compared in the same range of soil temperature and moisture before and after the tillage. The results showed that, after the tillage, SCE increased by 1.2-2.2 times; the soil temperature sensitivity increased by 36.1%-37.5%; and the soil moisture sensitivity increased by 140%-166%. Thus, the tillage-induced increase in SCE might partially be attributed to the increases in temperature and moisture sensitivity of SCE.展开更多
基金financially supported by the Joint Funds of the National Natural Science Foundation of China(U22A20609)the National Key Research and Development Program of China(2021YFD1901102-4)+2 种基金the State Key Laboratory of Integrative Sustainable Dryland Agriculture(in preparation)the Shanxi Agricultural University,China(202003-3)the Open Fund from the State Key Laboratory of Soil Environment and Nutrient Resources of Shanxi Province,China(2020002)。
文摘Tillage practices during the fallow period benefit water storage and yield in dryland wheat crops.However,there is currently no clarity on the responses of soil organic carbon(SOC),total nitrogen(TN),and available nutrients to tillage practices within the growing season.This study evaluated the effects of three tillage practices(NT,no tillage;SS,subsoil tillage;DT,deep tillage)over five years on soil physicochemical properties.Soil samples at harvest stage from the fifth year were analyzed to determine the soil aggregate and aggregate-associated C and N fractions.The results indicated that SS and DT improved grain yield,straw biomass and straw carbon return of wheat compared with NT.In contrast to DT and NT,SS favored SOC and TN concentrations and stocks by increasing the soil organic carbon sequestration rate(SOCSR)and soil nitrogen sequestration rate(TNSR)in the 0-40 cm layer.Higher SOC levels under SS and NT were associated with greater aggregate-associated C fractions,while TN was positively associated with soluble organic nitrogen(SON).Compared with DT,the NT and SS treatments improved soil available nutrients in the 0-20 cm layer.These findings suggest that SS is an excellent practice for increasing soil carbon,nitrogen and nutrient availability in dryland wheat fields in North China.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest (201503125, 201503105)the Chinese National High Technology Research and Development Program (2011AA100504)
文摘Limited water resources often result in reduced crop yield and low water productivity（WP）. In northwestern China, crop production is generally dependent on precipitation. Therefore, a variety of agricultural rainwater harvesting（ARH） techniques have been used for conserving soil moisture, ameliorating soil environment, increasing crop yield, and improving water use efficiency. A two-year（2013–2015） field experiment was conducted under a typical sub-humid drought-prone climate in Yangling（108°24′E, 34°20′N; 521 m a.s.l.）, Shaanxi Province, China, to explore the effects of mulching（same for summer maize and winter wheat） on soil moisture, soil temperature, crop water consumption, and crop yield with a winter wheat/summer maize rotation. Crops were planted in a ridge-furrow pattern and the treatments consisted of a transparent film mulch over the ridges（M1）, a crop straw mulch in the furrows（M2）, a transparent film mulch over the ridges and a crop straw mulch in the furrows（M3）, a black film mulch over the ridges and a crop straw mulch in the furrows（M4）, and a control with no mulch（CK）. Results showed that M4 was the best treatment for improving soil water storage and content, and decreasing crop water consumption during the summer maize and winter wheat rotation. In both maize and wheat seasons, M1 had a higher soil temperature than M2 and CK, and M3 had a higher soil temperature than M4. In the maize seasons, M4 had the highest yield, WP, and precipitation productivity（PP）, with the average values for these parameters increasing by 30.9%, 39.0%, and 31.0%, respectively, compared to those in CK. In the wheat seasons, however, M3 had the highest yield, WP, and PP, with the average values for these parameters being 23.7%, 26.7%, and 23.8% higher, respectively, than those in CK. Annual yield（maize and wheat yields combined） and WP did not differ significantly between M3 and M4. These results suggested that M3 and M4 may thus be the optimal ARH practices for the production of winter wheat and summer maize, respectively, in arid and semi-arid areas.
基金Projects supported by the National Natural Science Foundation of China (Nos. 49471016, 49771019 and 49890330)
文摘In order to explore the spatial variability of soil moisture near the interface of high/low stands, an experiment was conducted at Luancheng Experimental Station, Chinese Academy of Sciences, Hebei, China from May to June, 1996. By analyzing the observed soil moisture data, it shows that there exists an obvious turning point of soil moisture pattern from one side of the interface to another. The effect of drier soil closer to the interface in winter wheat field is obvious, which is mainly due to the better ventilation condition near the interface in winter wheat filed than in alfalfa field. The irrigation in large scale is one of the most important factors to control the spatial pattern of soil moisture while the small scale human disturbing activity, such as the stealing event occurred during our observation, does not change the spatial pattern of soil moisture obviously. Latent heat, calculated by Bowen ratio method based on our observed micrometeorological data, is shown larger in alfalfa than that in winter wheat both at earring stage from May 8 to 10 and mature stage from June 11 to 14. This fact, together with the larger ground temperature and a little bit larger wind velocity in lower layer, explains that the soil is drier in alfalfa than in winter wheat from May 8 to 10. While for the period from June 11 to 14, irrigation's effect changes the natural interrelationship of soil moisture with meteorology and ground temperature.
基金supported by the National Natural Science Foundation of China (No.71003092)the National Basic Research Program (973) of China (No.2010CB833504-2)
文摘As a conventional farming practice, tillage has lasted for thousands of years in Loess Plateau, China. Although recent studies show that tillage is a prominent culprit to soil carbon loss in croplands, few studies have investigated the influences of tillage on the responses of soil CO2 efflux （SCE） to soil temperature and moisture. Using a multi-channel automated CO2 efflux chamber system, we measured SCE in situ continuously before and after the conventional tillage in a rain fed wheat field of Loess Plateau, China. The changes in soil temperature and moisture sensitivities of SCE, denoted by the Q10 value and linear regression slope respectively, were compared in the same range of soil temperature and moisture before and after the tillage. The results showed that, after the tillage, SCE increased by 1.2-2.2 times; the soil temperature sensitivity increased by 36.1%-37.5%; and the soil moisture sensitivity increased by 140%-166%. Thus, the tillage-induced increase in SCE might partially be attributed to the increases in temperature and moisture sensitivity of SCE.
