鸡粪改良对铜尾矿基质中无机氮组分及3种豆科植物生长发育的影响

基质改良和耐性物种选择是重金属矿业废弃地生态修复的关键。本文通过室内盆栽试验,以4kg尾矿为植物盆栽基质,分别加入腐熟鸡粪0、8、16、32g混匀,记作MA0（CK）、MA8、MA16、MA32处理方式,研究不同比例腐熟鸡粪改良对铜尾矿基质中无机氮组分及3种豆科植物决明（Cassia tora）、田菁（Sesbania cannabina）、菽麻（Crotalaria juncea）生长发育的影响。结果表明,添加鸡粪改良处理后,3种豆科植物生长的尾矿基质中均以硝态氮为有效氮的主要形态,总无机氮含量为17.96～44.82mg·kg-1。其中菽麻MA32处理组尾矿基质中铵态氮含量（5.31mg·kg-1）最高,菽麻MA16处理组尾矿基质中硝态氮含量（43.06mg·kg-1）和总无机氮含量（44.82mg·kg-1）最高。MA16处理时,田菁和菽麻叶绿素a、叶绿素b、叶绿素a＋b值均表现最大。3种豆科植物叶绿素a/b为0.92～1.08。在同一鸡粪比例处理中,菽麻叶绿素a、叶绿素b、叶绿素a＋b值均显著高于决明和田菁（P〈0.05）。鸡粪改良铜尾矿基质能够促进3种豆科植物生长,植物株高、冠幅、根长均增加,并且随着生长期延长,增加明显。其中MA32处理菽麻70d株高（94.40cm）最大,阻止尾矿风蚀水蚀的效果最好。综合分析表明,MA16处理方式可作为鸡粪改良铜尾矿基质理想的比例模式,菽麻可作为铜尾矿生态修复优选植物种。

Effect of Chicken Manure-Amended on Inorganic Nitrogen Components of Copper Mine Tailings and Growing Development of Three Leguminous Species

Substrate amendment and tolerant species selection is the key to the ecological restoration for heavy metals mining wastelands. In this work, several potted tests were performed using 4 kg tailings as the substrate to explore the effects of different proportions of composted chicken manure-amended on inorganic nitrogen components of copper mine tailings and growing development of three legumes（Cassia tora, Sesbania cannabina and Crotalaria juncea）. In each test, four levels of compost chicken manure were added at 0 g, 8 g, 16 g, and 32 g, respectively and the treatment numbers were recorded as MA0（CK）, MA8, MA16 and MA32, respectively. After adding chicken manure, the main form of available nitrogen in the tailings substrate of three legumes was nitrate nitrogen and total inorganic nitrogen content achieved 17.96～44.82 mg·kg-1. Among these, the content of ammonium nitrogen（5.31 mg·kg-1） reached the highest in the tailings substrate of C. juncea MA32 treatment and the content of nitrate nitrogen（43.06 mg·kg-1） and total inorganic nitrogen（44.82 mg·kg-1） were the highest in the tailings substrate of C. juncea MA16 treatment. The highest contents for chlorophyll a, chlorophyll b and chlorophyll a＋b were observed in MA16 treatment of S. cannabina and C. juncea. The ratios of chlorophyll a/b was 0.92~1.08 in three legumes. In the same chicken manure proportion treatment, the contents for chlorophyll a, chlorophyll b and chlorophyll a＋b of C. juncea were significant higher than those of C. tora and S. cannabina（P0.05）. Chicken manure-amended copper mine tailings substrate could promote three legumes growth by improving its height, crown width and root length, increased significantly along with the growth period extended. The plant height（94.40 cm） of C. juncea on the 70th day was the highest and the effect to prevent tailings wind-water erosion was the best in MA32 treatment. These results demonstrate that the MA16 treatment was a suitable method for copper mine tailings amendment with chicken manure and Crotalaria juncea was found to be the favorable plant for ecological restoration of copper mine tailings.