Crop consumptive water use is recognized as a key element to understand regional water management performance. This study documents an attempt to apply a regional evapotranspiration model(SEBAL) and crop information...Crop consumptive water use is recognized as a key element to understand regional water management performance. This study documents an attempt to apply a regional evapotranspiration model(SEBAL) and crop information for assessment of regional crop(summer maize and winter wheat) actual evapotranspiration(ET a) in Huang-Huai-Hai(3H) Plain, China. The average seasonal ET a of summer maize and winter wheat were 354.8 and 521.5 mm respectively in 3H Plain. A high-ET a belt of summer maize occurs in piedmont plain, while a low ET a area was found in the hill-irrigable land and dry land area. For winter wheat, a high-ET a area was located in the middle part of 3H Plain, including low plain-hydropenia irrigable land and dry land, hill-irrigable land and dry land, and basin-irrigable land and dry land. Spatial analysis demonstrated a linear relationship between crop ET a, normalized difference vegetation index(NDVI), and the land surface temperature(LST). A stronger relationship between ET a and NDVI was found in the metaphase and last phase than other crop growing phase, as indicated by higher correlation coefficient values. Additionally, higher correlation coefficients were detected between ET a and LST than that between ET a and NDVI, and this significant relationship ran through the entire crop growing season. ET a in the summer maize growing season showed a significant relationship with longitude, while ET a in the winter wheat growing season showed a significant relationship with latitude. The results of this study will serve as baseline information for water resources management of 3H Plain.展开更多
Ammonia (NH_3) emissions should be mitigated to improve environmental quality.Croplands are one of the largest NH_3sources,they must be managed properly to reduce their emissions while achieving the target yields.Here...Ammonia (NH_3) emissions should be mitigated to improve environmental quality.Croplands are one of the largest NH_3sources,they must be managed properly to reduce their emissions while achieving the target yields.Herein,we report the NH_3 emissions,crop yield and changes in soil fertility in a long-term trial with various fertilization regimes,to explore whether NH_3 emissions can be significantly reduced using the 4R nutrient stewardship (4Rs),and its interaction with the organic amendments (i.e.,manure and straw) in a wheat–maize rotation.Implementing the 4Rs significantly reduced NH_3 emissions to 6 kg N ha~(–1) yr~(–1) and the emission factor to 1.72%,without compromising grain yield (12.37 Mg ha~(–1) yr~(–1))and soil fertility (soil organic carbon of 7.58 g kg~(–1)) compared to the conventional chemical N management.When using the 4R plus manure,NH_3 emissions (7 kg N ha~(–1) yr~(–1)) and the emission factor (1.74%) were as low as 4Rs,and grain yield and soil organic carbon increased to 14.79 Mg ha~(–1) yr~(–1) and 10.09 g kg~(–1),respectively.Partial manure substitution not only significantly reduced NH_3 emissions but also increased crop yields and improved soil fertility,compared to conventional chemical N management.Straw return exerted a minor effect on NH_3 emissions.These results highlight that 4R plus manure,which couples nitrogen and carbon management can help achieve both high yields and low environmental costs.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
Biosolids were applied with urea to produce a granulated organo-mineral fertiliser (OMF) for application by farm fertiliser equipment to a range of agricultural crops. The recommended rates of nitrogen, phosphate and ...Biosolids were applied with urea to produce a granulated organo-mineral fertiliser (OMF) for application by farm fertiliser equipment to a range of agricultural crops. The recommended rates of nitrogen, phosphate and potash were calculated for the test crops using “The Fertiliser Manual”, which assesses the nutrient requirement based on previous cropping, rainfall and soil index. The OMF produced similar crop yields compared to ammonium nitrate fertiliser when applied as a top-dressing to winter wheat, forage maize and grass cut for silage in the cropping years 2010 to 2014. In 2012 the grain yield of spring barley top-dressed with OMF was significantly lower than the conventional fertiliser treatment, due to dry conditions following application. For this reason it is recommended that OMF is incorporated into the seedbed for spring sown crops and The Safe Sludge Matrix guidelines followed. The experimental work presented shows that OMF can be used in sustainable crop production systems as a source of nitrogen and phosphorus for a range of agricultural crops.展开更多
基金supported by the National Key Technologies R&D Program of China during the 12th Five-Year Plan period (2012BAD09B01)the National Basic Research Program of China (973 Program, 2012CB955904)the National Science Foundation for Young Scientists of China (41401510)
文摘Crop consumptive water use is recognized as a key element to understand regional water management performance. This study documents an attempt to apply a regional evapotranspiration model(SEBAL) and crop information for assessment of regional crop(summer maize and winter wheat) actual evapotranspiration(ET a) in Huang-Huai-Hai(3H) Plain, China. The average seasonal ET a of summer maize and winter wheat were 354.8 and 521.5 mm respectively in 3H Plain. A high-ET a belt of summer maize occurs in piedmont plain, while a low ET a area was found in the hill-irrigable land and dry land area. For winter wheat, a high-ET a area was located in the middle part of 3H Plain, including low plain-hydropenia irrigable land and dry land, hill-irrigable land and dry land, and basin-irrigable land and dry land. Spatial analysis demonstrated a linear relationship between crop ET a, normalized difference vegetation index(NDVI), and the land surface temperature(LST). A stronger relationship between ET a and NDVI was found in the metaphase and last phase than other crop growing phase, as indicated by higher correlation coefficient values. Additionally, higher correlation coefficients were detected between ET a and LST than that between ET a and NDVI, and this significant relationship ran through the entire crop growing season. ET a in the summer maize growing season showed a significant relationship with longitude, while ET a in the winter wheat growing season showed a significant relationship with latitude. The results of this study will serve as baseline information for water resources management of 3H Plain.
基金supported by the Hainan Key Research and Development Project, China (ZDYF2021XDNY184)the Hainan Provincial Natural Science Foundation of China (422RC597)+2 种基金the National Natural Science Foundation of China (41830751)the Hainan Major Science and Technology Program, China (ZDKJ2021008)the Hainan University Startup Fund,China (KYQD(ZR)-20098)。
文摘Ammonia (NH_3) emissions should be mitigated to improve environmental quality.Croplands are one of the largest NH_3sources,they must be managed properly to reduce their emissions while achieving the target yields.Herein,we report the NH_3 emissions,crop yield and changes in soil fertility in a long-term trial with various fertilization regimes,to explore whether NH_3 emissions can be significantly reduced using the 4R nutrient stewardship (4Rs),and its interaction with the organic amendments (i.e.,manure and straw) in a wheat–maize rotation.Implementing the 4Rs significantly reduced NH_3 emissions to 6 kg N ha~(–1) yr~(–1) and the emission factor to 1.72%,without compromising grain yield (12.37 Mg ha~(–1) yr~(–1))and soil fertility (soil organic carbon of 7.58 g kg~(–1)) compared to the conventional chemical N management.When using the 4R plus manure,NH_3 emissions (7 kg N ha~(–1) yr~(–1)) and the emission factor (1.74%) were as low as 4Rs,and grain yield and soil organic carbon increased to 14.79 Mg ha~(–1) yr~(–1) and 10.09 g kg~(–1),respectively.Partial manure substitution not only significantly reduced NH_3 emissions but also increased crop yields and improved soil fertility,compared to conventional chemical N management.Straw return exerted a minor effect on NH_3 emissions.These results highlight that 4R plus manure,which couples nitrogen and carbon management can help achieve both high yields and low environmental costs.
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.
文摘Biosolids were applied with urea to produce a granulated organo-mineral fertiliser (OMF) for application by farm fertiliser equipment to a range of agricultural crops. The recommended rates of nitrogen, phosphate and potash were calculated for the test crops using “The Fertiliser Manual”, which assesses the nutrient requirement based on previous cropping, rainfall and soil index. The OMF produced similar crop yields compared to ammonium nitrate fertiliser when applied as a top-dressing to winter wheat, forage maize and grass cut for silage in the cropping years 2010 to 2014. In 2012 the grain yield of spring barley top-dressed with OMF was significantly lower than the conventional fertiliser treatment, due to dry conditions following application. For this reason it is recommended that OMF is incorporated into the seedbed for spring sown crops and The Safe Sludge Matrix guidelines followed. The experimental work presented shows that OMF can be used in sustainable crop production systems as a source of nitrogen and phosphorus for a range of agricultural crops.