Guo Nan, Chi Guang Yu, Shi Yi, Chen Xin
Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
University of Chinese Academy of Sciences, Beijing 100049, China.
Ying Yong Sheng Tai Xue Bao. 2019 Sep;30(9):3164-3174. doi: 10.13287/j.1001-9332.201909.038.
To achieve the goal of remediation while producing for farmland contaminated by Cd, maize and grain amaranth (Amaranthus hypochondriacus) were planted on farmland contaminated by Cd in five different intercropping modes, including alternating wide-narrow-row of maize and single-row grain amaranth intercropped between wide rows (T), alternating wide-narrow-row of maize and double-row grain amaranth intercropped between wide rows (T), equidistant double-row maize and single-row grain amaranth intercropped between rows (T), equidistant double-row maize and double-row grain amaranth intercropped between rows (T), maize and grain amaranth intercropped with equal four rows (T), while maize (CK) and grain amaranth (CK) single planted as control to explore the effects of different intercropping modes on growth and Cd accumulation of crops and hyper-accumulation plants (A. hypochondriacus). The results showed that: 1) Compared with mono-culture (CK), grain yield of maize per plant showed an increasing trend in intercropping modes. The grain yield of maize in T increased by 10.5%, while that in T and T decreased by 6.3% and 5.4% respectively, and that in T or T did not change compared with monoculture of maize. The aboveground biomass per plant and yield per unit area of grain amaranth decreased by 69.5%-95.7% and 83.9%-96.9% in intercropping modes respectively compared with monoculture (CK). 2) The Cd content of maize grain showed an increasing trend in intercropping modes compared with monoculture (CK). The Cd content of grain amaranth showed a decreasing trend in intercropping modes compared with monoculture (CK2). 3) Compared with monoculture (CK2), the enrichment coefficient, transport coefficient, and effective transport coefficient of grain amaranth all showed an increasing trend in intercropping modes, while the aboveground Cd extraction amount per plant and per unit area of grain amaranth decreased by 40.4%-86.7% and 70.4%-88.9% in intercropping modes, respectively. The total amount of Cd extraction per unit area of maize and grain amaranth in intercropping modes was significantly higher than that in monoculture of maize and lower than that in monoculture of grain amaranth. 4) The content of available Cd in maize rhizosphere soil and the content of total/available Cd in grain amaranth rhizosphere soil both showed an increasing trend in intercropping modes compared with monoculture of both crop, but it had no significant effect on non-rhizosphere soil. In this study, T was beneficial to increase maize grain yield, while T was beneficial to maximize the Cd extraction amount of grain amaranth.
为了实现镉污染农田修复的同时进行生产的目标，在镉污染农田上采用5种不同间作模式种植玉米和籽粒苋（Amaranthus hypochondriacus），包括玉米宽窄行交替、宽行中间单作籽粒苋（T），玉米宽窄行交替、宽行中间双作籽粒苋（T），玉米等行距双行、行间距中间单作籽粒苋（T），玉米等行距双行、行间距中间双作籽粒苋（T），玉米和籽粒苋等行距四行间作（T），同时单种玉米（CK）和单种籽粒苋（CK）作为对照，以探究不同间作模式对作物及超富集植物（籽粒苋）生长和镉积累的影响。结果表明：1）与单作（CK）相比，间作模式下玉米单株籽粒产量呈增加趋势。T模式下玉米籽粒产量提高了10.5%，而T和T模式下分别降低了6.3%和5.4%，T或T模式下与玉米单作相比无变化。与单作（CK）相比，间作模式下籽粒苋单株地上部生物量和单位面积产量分别降低了69.5% - 95.7%和83.9% - 96.9%。2）与单作（CK）相比，间作模式下玉米籽粒镉含量呈增加趋势。与单作（CK2）相比，间作模式下籽粒苋镉含量呈降低趋势。3）与单作（CK2）相比，间作模式下籽粒苋的富集系数、转运系数和有效转运系数均呈增加趋势，而间作模式下籽粒苋单株地上部镉提取量和单位面积镉提取量分别降低了40.4% - 86.7%和70.4% - 88.9%。间作模式下玉米和籽粒苋单位面积镉提取总量显著高于玉米单作，低于籽粒苋单作。4）与两种作物单作相比，间作模式下玉米根际土壤有效镉含量以及籽粒苋根际土壤总镉/有效镉含量均呈增加趋势，但对非根际土壤无显著影响。本研究中，T模式有利于提高玉米籽粒产量，而T模式有利于使籽粒苋镉提取量最大化。
