This study aimed to comprehensive evaluation of different winter green manure on characterization of nitrogen uptake and utilization, to provide the basis for N fertilizer reasonable operation and characteristics impr...This study aimed to comprehensive evaluation of different winter green manure on characterization of nitrogen uptake and utilization, to provide the basis for N fertilizer reasonable operation and characteristics improvement of nitrogen nutrition in rice high-yield cultivation. This experiment was set to compare milk vetch, rapeseed,ryegrass and mixed of green manure on rice yield, rice growth dynamics and nitrogen uptake and utilization in rice. The results showed that among 4 different winter green manure, the treatment of MV-R-R(milk vetch-rice-rice) for the early rice yield was the most than others treatments. Compared with RG-R-R(ryegrass-rice-rice), RPR-R(rapeseed-rice-rice), MS-R-R(mixed green manure-rice-rice), the treatment of MVR-R inceased by 6.61%, 3.29%, 0.78%, respectively. The treatment of MV-R-R in N content in plant of rice was maximized in the tillering, booting, heading and maturity periods, respectively higher than the average of other treatments 9.68%, 19.72%,6.23% and 8.66%. At tillering, booting, heading and maturity, the treatment of MV-R-R were the highest in N uptake, RP-R-R minimum. The N periodic accumulation for MV-R-R were higher than other treatments in the tillering to booting, booting to heading and heading to maturity periods. The rates respectively were 21.81%, 68.73% and286.5%. In addition, N periodic accumulation and its ratio to total in the heading to maturity was minimum, maximum before tillering under green manure rotation system.So the cropping system of milk vetch-rice-rice could increase nitrogen use efficiency and improve N cycling.展开更多
Dissimilatory Fe(Ⅲ) reduction is an important process in the geochemical cycle of iron in anoxic environment. As the main products of dissimilatory iron reduction, the Fe(Ⅱ) species accumulation could indicate t...Dissimilatory Fe(Ⅲ) reduction is an important process in the geochemical cycle of iron in anoxic environment. As the main products of dissimilatory iron reduction, the Fe(Ⅱ) species accumulation could indicate the reduction ability. The effects of different green manures on Fe(Ⅲ) reduction in paddy soil were explored based on a 31-year rice-rice-winter green manure cropping experiment. Four treatments were involved, i.e., rice-rice-milk vetch (RRV), rice-rice-rape (RRP), rice-rice-ryegrass (RRG) and rice-rice-winter fallow (RRF). Soils were sampled at flowering stage of milk vetch and rape (S1), before transplantation (S2), at tillering (S3), jointing (S4), and mature (S5) stages of the early rice, and after the harvest of the late rice (S6). The contents of TFeHa (HCI-extractable total Fe), Fe(Ⅱ)HCI (HCI-extractable Fe(Ⅱ) species) and Fe(Ⅲ)HCI (HCI- extractable Fe(Ⅲ) species) were measured. The correlations among those Fe species with selected soil environmental factors and the dynamic characteristics of Fe(Ⅱ)HCI accumulation were investigated. The results showed that TFeHc~ in RRF was significantly higher than those in the green manure treatments at most of the sampling stages. Fe(II)Ha increased rapidly after the incorporation of green manures in all treatments and kept rising with the growth of early rice. Fe(Ⅱ)Ha in RRG was quite different from those in other treatments, i.e., it reached the highest at the S2 stage, then increased slowly and became the lowest one at the S4 and S5 stages. Fe(Ⅲ)Ha showed oppositely, and Fe(Ⅱ)HCI/Fe(Ⅲ)HCI performed similarly to Fe(Ⅱ)HCI The maximum accumulation potential of Fe(Ⅱ)HCI was significantly higher in RRF, while the highest maximum reaction rate of Fe(Ⅱ)Ha accumulation appeared in RRG. Significant correlations were found between the indexes of Fe(Ⅱ)HCI accumulation and soil pH, oxidation-reduction potential (Eh) and total organic acids, respectively. In together, we found that long-term application of green manures decreased the TFeHa in red paddy soils, but promoted the ability of Fe(lll) reduction, especially the ryegrass; Fe(Ⅱ)Ha increased along with the growth of rice and was affected by soil conditions and environmental factors, especially the water and redox ability.展开更多
基金Supported by Jiangxi Agricultural University Students’Platform for Innovation and Entrepreneurship Training Program(DC201305)Key Projects in the National Science&Technology Pillar Program(2012BAD14B14-01)~~
文摘This study aimed to comprehensive evaluation of different winter green manure on characterization of nitrogen uptake and utilization, to provide the basis for N fertilizer reasonable operation and characteristics improvement of nitrogen nutrition in rice high-yield cultivation. This experiment was set to compare milk vetch, rapeseed,ryegrass and mixed of green manure on rice yield, rice growth dynamics and nitrogen uptake and utilization in rice. The results showed that among 4 different winter green manure, the treatment of MV-R-R(milk vetch-rice-rice) for the early rice yield was the most than others treatments. Compared with RG-R-R(ryegrass-rice-rice), RPR-R(rapeseed-rice-rice), MS-R-R(mixed green manure-rice-rice), the treatment of MVR-R inceased by 6.61%, 3.29%, 0.78%, respectively. The treatment of MV-R-R in N content in plant of rice was maximized in the tillering, booting, heading and maturity periods, respectively higher than the average of other treatments 9.68%, 19.72%,6.23% and 8.66%. At tillering, booting, heading and maturity, the treatment of MV-R-R were the highest in N uptake, RP-R-R minimum. The N periodic accumulation for MV-R-R were higher than other treatments in the tillering to booting, booting to heading and heading to maturity periods. The rates respectively were 21.81%, 68.73% and286.5%. In addition, N periodic accumulation and its ratio to total in the heading to maturity was minimum, maximum before tillering under green manure rotation system.So the cropping system of milk vetch-rice-rice could increase nitrogen use efficiency and improve N cycling.
基金supported by the Special Fund for Agroscientific Research in the Public Interest,China(201103005)the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(2013–2017)
文摘Dissimilatory Fe(Ⅲ) reduction is an important process in the geochemical cycle of iron in anoxic environment. As the main products of dissimilatory iron reduction, the Fe(Ⅱ) species accumulation could indicate the reduction ability. The effects of different green manures on Fe(Ⅲ) reduction in paddy soil were explored based on a 31-year rice-rice-winter green manure cropping experiment. Four treatments were involved, i.e., rice-rice-milk vetch (RRV), rice-rice-rape (RRP), rice-rice-ryegrass (RRG) and rice-rice-winter fallow (RRF). Soils were sampled at flowering stage of milk vetch and rape (S1), before transplantation (S2), at tillering (S3), jointing (S4), and mature (S5) stages of the early rice, and after the harvest of the late rice (S6). The contents of TFeHa (HCI-extractable total Fe), Fe(Ⅱ)HCI (HCI-extractable Fe(Ⅱ) species) and Fe(Ⅲ)HCI (HCI- extractable Fe(Ⅲ) species) were measured. The correlations among those Fe species with selected soil environmental factors and the dynamic characteristics of Fe(Ⅱ)HCI accumulation were investigated. The results showed that TFeHc~ in RRF was significantly higher than those in the green manure treatments at most of the sampling stages. Fe(II)Ha increased rapidly after the incorporation of green manures in all treatments and kept rising with the growth of early rice. Fe(Ⅱ)Ha in RRG was quite different from those in other treatments, i.e., it reached the highest at the S2 stage, then increased slowly and became the lowest one at the S4 and S5 stages. Fe(Ⅲ)Ha showed oppositely, and Fe(Ⅱ)HCI/Fe(Ⅲ)HCI performed similarly to Fe(Ⅱ)HCI The maximum accumulation potential of Fe(Ⅱ)HCI was significantly higher in RRF, while the highest maximum reaction rate of Fe(Ⅱ)Ha accumulation appeared in RRG. Significant correlations were found between the indexes of Fe(Ⅱ)HCI accumulation and soil pH, oxidation-reduction potential (Eh) and total organic acids, respectively. In together, we found that long-term application of green manures decreased the TFeHa in red paddy soils, but promoted the ability of Fe(lll) reduction, especially the ryegrass; Fe(Ⅱ)Ha increased along with the growth of rice and was affected by soil conditions and environmental factors, especially the water and redox ability.