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In recent years, sewage irrigation and its impact on the environment has become an important issue for many countries in the efficient use of water resources, urban sewage treatment, agricultural ecological environment and other areas of growing concern. The so-called sewage water quality changes in terms of physical properties, chemical properties and biological properties of the water through human activities. Often contain one or several different concentrations of heavy metal ions in the sewage, farmland irrigation with wastewater containing heavy metal ions, these heavy metal ions residues in soil and plants on the growth of plants and through the food chain to human health a series of direct or indirect harm. The hazards of heavy metals on plants of different types, different concentrations and different heavy metal ions or ion combinations. In this study, as the test plant potted cabbage, Chinese cabbage the whole growth period is divided into three growth stages containing the different concentrations Cu 2 , Cd 2 water simulation sewage wastewater for irrigation. The the different concentrations Cu 2 , Cd 2 single and composite processing of cabbage at different growth stages root, leaf dry matter accumulation; different concentrations of Cu 2 , Cd 2 single and composite processing cabbage chlorophyll; different concentrations of Cu 2 , Cd 2 single and combined treatments accumulated concentration in the roots and leaves of cabbage Cu 2 , Cd 2 , the main results and conclusions are as follows: (1) the concentration of Cu 2 or Cd of 2 single treatment have shown inhibition of the growth stages Liangcha cabbage dry matter accumulation, and both with the concentration increasing significantly increased the degree of inhibition of dry matter accumulation The degree of inhibition of the cabbage dry matter accumulation, but the two ions with different concentrations in different parts of the different crop, different growth stages and cabbage (roots or leaves) are very different. The from the different concentrations Cu 2 , Cd 2 single treatment of the root, leaf dry matter accumulation in looking at the impact of the various growth stages Liangcha cabbage, cabbage early growth stage under Cu 2 , Cd 2 less affected late in the growth inhibition increases, ie cabbage Cu 2 , Cd 2 more sensitive, this case contains the ions sewage wastewater for irrigation will seriously affect the amount of the cabbage dry matter accumulation. (2) Cu 2 , Cd 2 concentration compound on the cabbage dry matter accumulation showed inhibition of different concentrations of a combination of different stubble and different growth stages suppression to different degrees. High concentrations of Cu 2 , Cd 2 composite various growth stages of cabbage root and leaf dry matter accumulation inhibition performance for collaborative; summer crop of cabbage root dry matter accumulation high concentrations of Cu 2 coercion the lower concentration Cd 2 is not sensitive. (3) In this study, different concentrations of Cu 2 of Cd 2 the single processing had certain inhibition of the growth phase of chlorophyll Liangcha cabbage, where high concentrations of Cd < sup> 2 single processing (AH) The chlorophyll synthesis inhibition is less than the low concentration of Cd 2 single treatment (AL), from of Cd 2 of chlorophyll point of view, cabbage growth late of Cd 2 more sensitive; of Cu 2 single processing cabbage chlorophyll inhibition with Cu 2 the concentration increases. Statistical analysis showed that low concentrations of Cu 2 chlorophyll synthesis of the first two Liangcha cabbage growth stage, high concentrations of Cu 2 handle on the summer crop of cabbage chlorophyll inhibition of the growth of late, and the whole growth period of winter crop of cabbage. (4) different concentrations of Cu 2 , Cd 2 composite processing dampen the growth stage of the Liangcha cabbage chlorophyll, with low concentrations of Cd 2 composite Cu 2 increasing the concentration of chlorophyll content was significantly reduced; in high concentrations of Cd 2 added under high concentration of Cu 2 will add to the destruction or inhibition of its third growth phase of the summer crop of cabbage and winter stubble cabbage whole growth chlorophyll content, performance Cu 2 , Cd the synergy 2 elements; low concentration Cu 2 with different concentrations of Cd 2 composite processing of chlorophyll in the late winter crop of cabbage growth impact than summer crop to be big. (5) different concentrations of Cu 2 , Cd 2 single process, the growing of two the cabbage root system and leaves Cu 2 Cd 2 concentrations than the corresponding water control treatment CK were significantly increased, in a single treatment of low concentration of Cd 2 (AL), the growing of two cabbage roots and leaves of Cd < sup> 2 concentration of approximately of CK 2.1 times and 1.7 times, respectively, in high concentrations of Cd 2 single treatment (AH) the Cd under Liangcha cabbage roots and leaves 2 concentration ratio of CK treatment were 7.4 to 11.9 times and 5.7 to 8.6 times; in low concentrations of Cu 2 single treatment (BL), Liangcha cabbage each growth stage roots and leaves in the Cu 2 the accumulated concentration are corresponding control treatment of CK about 2.1 times; high concentrations of Cu 2 single treatment (BH), Liangcha cabbage the blade in Cu in 2 concentration of about 4.2 to 5.0 of the CK treatment times, with its roots of of Cu 2 CK treatment concentration of about of about 5.1 to 5.7 times decrease Cu 2 concentration increased, Cu 2 is also increasing the concentration gradient, from the roots to the ground [w1]. (6) different concentrations of Cu 2 , Cd 2 composite processing, Liangcha cabbage vivo the of Cu 2 , of Cd the 2 < / sup> concentration compared to the corresponding control treatment CK have increased by Cu in roots and leaves of cabbage 2 , Cd 2 of the concentration of Cu 2 < / sup>, of Cd the 2 composite concentration, different stubble and different growth stages and different.
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