长期造纸废水灌溉条件下湿地土壤特性研究

发布时间：2018-06-14 19:21

本文选题：造纸废水灌溉 + 湿地土壤　；参考：《沈阳农业大学》2017年硕士论文

【摘要】：由于全球气候不断变暖和工业化程度的提高,湿地面积呈现不断缩减状态。辽河口湿地面临严峻的水资源短缺问题,同时地下水补给条件差,天然降水不够,位于湿地内部的造纸厂沿河分布,废水流经湿地,且废水排放量大,湿地废水灌溉不可避免。为研究不同土层及不同生育期湿地土壤特性的变化,分析长期废水灌溉条件下湿地土壤中各指标含量的迁移特征。利用小试装置模拟辽河口天然芦苇湿地,采用CODcr浓度分别为50mg·L-1、175mg·L-1、300mg·L-1的造纸废水,分别在不同生育期(出苗期、展叶期、拔节期、抽穗开花期和成熟期)进行灌溉,以2009年土壤容重、孔隙度、有机质、总氮、总磷及重金属等含量为基底值,从2009年～2015年,每年进行灌溉,测定经过长期灌溉后2015年土壤容重、孔隙度、有机质、总氮、总磷及重金属等含量,分析2009年～2015年各含量的比值。主要的研究结果如下:(1)经过长期灌溉不同质量浓度的造纸废水后,容重随土层深度的增加,容重不断减少。孔隙度随着土层深度的增加,孔隙度呈不断减少的趋势。长期灌溉不同浓度造纸废水后,土壤容重变化趋势随废水灌溉质量浓度增加,土壤容重逐渐减少。在芦苇不同生育期灌溉不同浓度的造纸废水,土壤孔隙度随着土层深度的增加,孔隙度不断减小,在0～5cm 土层孔隙度达到最大值。质量浓度为300mg·L-1处理时,土壤孔隙度变化最大,175mg·L-1处理时变化量最小。(2)经过长期灌溉不同质量浓度的造纸废水后,对土壤有机质含量及变化量的影响,在土壤表层中有机质含量最高为5.01%。相反底层土壤有机质变化量增长率最高为1.88%。芦苇不同生育期灌溉不同浓度的造纸废水,在0～5cm 土层,质量浓度为300mg·L-1处理时,土壤有机质含量增长率最高为3.97%。而芦苇处在展叶期时,质量浓度为50mg·L-1处理时,在0～5cm 土层有机质含量增长率最高为3.62%。抽穗开花期时土壤中有机质含量积累较多,此时芦苇对有机质的吸量较少,使大量有机质积累在土壤中。(3)经过长期灌溉不同质量浓度的造纸废水后,在芦苇不同生育期时,土壤中总磷在0～5cm 土层中含量最大为0.75g·kg-1。质量浓度为300mg·L-1处理总磷含量最大,质量浓度为50mg·L-1处理总磷含量最小。土壤中总氮含量随生育期呈现规律为:出苗期抽穗开花期展叶期成熟期快速生长期。土壤中总氮变化量随灌溉质量浓度不同,没有很好的规律可循,但随土层深度的增加,土壤中总氮变化量逐渐减少。(4)经过长期灌溉不同质量浓度的造纸废水后,土壤中铅离子在5～10cm 土层中含量最大为62.39mg·kg-1,在40～60 土层中含量最小为45.63mg·kg-1。结果表明,中上层土壤铅离子含量大于底层铅离子含量,原因可能为芦苇对表层铅离子吸收的较少,使大量铅离子在表层产生积累。结果表明:随着废水灌溉时间的增长,土壤中铅离子含量不断增加,使得铅离子变化量显著增加。底层土壤铜离子含量最小为12.53mg·kg-1,废水中的铜离子由于土壤颗粒吸附的作用,大量铜离子富集在土壤中上层;土壤镉离子含量变化不均,大量的镉离子富集在土壤中层和底层,表层土壤中镉离子含量相对较少。表层镉离子变化量最大为2.00mg·kg-1。大量的铬离子含量富集在土壤表层为53.76mg·kg-1,说明芦苇对表层土壤中的铬离子吸收较少。中上层土壤锰离子含量明显大于底层锰离子含量,说明废水灌溉后,由于芦苇对锰离子吸收的较弱所导致。土壤锰离子变化量在不同土层各有分布,且在中下层分布较多;锌离子含量在不同土层中没有很好的规律可循,说明并不是越底层或表层,其锌离子含量就越大或越小,土壤锌离子变化量在不同土层各有分布,且随着土层深度增加,变化量逐渐减少。(5)芦苇不同生长期灌溉不同浓度造纸废水,土壤铅离子含量在质量浓度为300mg·L-1处理时,铅离子含量最大,质量浓度为50mg·L-1处理时,土壤中铅离子含量最小。在5～10cm土层铅离子含量最高为62.39mg·kg-1。土壤铜离子在各层的分布比较相似。在5～10cm土层中,铜离子含量最大为59.49mg·kg-1,在40～60cm土层中,铜离子含量最小为45.28mg·kg-1。成熟期土壤中铜离子变化量最大,说明在成熟期灌溉造纸废水后,芦苇对土壤中铜离子吸收较弱。土壤镉离子在0～5cm土层,质量浓度为300mg·L-1处理含量最高。镉离子变化量在质量浓度300mg·L-1处理的变化量最大,50mg·L-1处理变化量最小。土壤铬离子含量在0～5cm土层中含量最高。灌溉废水质量浓度越大,土壤中的铬离子含量越多。铬离子变化量随芦苇生育期的变化趋势为成熟期抽穗开花期拔节期展叶期出苗期。土壤中锰离子含量在质量浓度300mg·L-1处理时,在0～10cm土层中锰离子含量最大,之后在40～60cm土层锰离子含量最小。锰离子变化量与锰离子含量变化相似。土壤中锌离子含量随着灌溉质量浓度的增加,锌离子含量越大。土壤锌离子变化量随生长期变化规律为成熟期拔节期抽穗开花期展叶期出苗期。灌溉不同质量浓度的造纸废水与土壤理化性质指标具有显著相关性。
[Abstract]:The wetland area is constantly shrinking because of the continuous warming and industrialization of the global climate. The Liaohe estuary wetland is facing a severe shortage of water resources. At the same time, the condition of groundwater recharge is poor, and the natural precipitation is not enough. The paper mill located inside the wetland is distributed along the river, the waste water flows through the wetland, and the wastewater discharge is large, the wetland wastewater irrigation is irrigated. In order to study the change of soil characteristics in different soil layers and different growth stages, the migration characteristics of each index in wetland soil under the condition of long term wastewater irrigation were analyzed. The small test device was used to simulate the natural reed wetland in the Liaohe River Estuary, and the paper wastewater with CODcr concentration of 50mg L-1175mg. L-1300mg. L-1, respectively, was different. The growth period (emergence period, leaf spreading stage, jointing stage, heading flowering period and mature period) was irrigated, with soil bulk density, porosity, organic matter, total nitrogen, total phosphorus and heavy metals in 2009 as the base value. From 2009 to 2015, irrigation was conducted every year to determine the soil bulk density, porosity, organic matter, total nitrogen, total phosphorus and weight after a long period of irrigation in 2015. The contents of metal and other contents were analyzed from 2009 to 2015. The main results were as follows: (1) after long term irrigation, the bulk density decreased with the depth of soil layer and the porosity decreased with the depth of soil layer. After water, the change trend of soil bulk density increases with the concentration of wastewater irrigation, and the soil bulk density decreases gradually. The porosity of soil porosity decreases with the depth of soil layer, and the porosity reaches the maximum value in 0 ~ 5cm soil layer. Soil porosity is 300mg. L-1 treatment. The change of gap degree is the most, the change of 175mg L-1 treatment is the smallest. (2) after long-term irrigation of different mass concentration of papermaking wastewater, the soil organic matter content and change amount, the highest organic matter content in the soil surface is 5.01%. on the contrary, the highest growth rate of the organic matter in the bottom soil is the different growth period irrigation of the 1.88%. reed. In the 0 ~ 5cm soil layer, the increase rate of soil organic matter content was the highest when the mass concentration was 300mg L-1. When the reed was in the spreading stage, the mass concentration was 50mg. L-1 treatment, the highest increase rate of organic matter in the 0 to 5cm soil layer was the accumulation of organic matter content in the soil at the time of 3.62%. heading. Reed has less absorption of organic matter and accumulates a large amount of organic matter in soil. (3) after long term irrigation of paper wastewater with different mass concentration, the maximum content of total phosphorus in soil in 0 ~ 5cm soil layer is 0.75g. Kg-1. in different growth stages of reed. The concentration of total phosphorus is the largest in the treatment of 300mg. L-1, and the mass concentration is 50mg L-1 treatment. The total nitrogen content of the soil was the lowest. The total nitrogen content in the soil showed a regular period with the growth period. The change of total nitrogen in the soil was different with the irrigation quality, but the change of total nitrogen in the soil decreased with the depth of soil layer. (4) after a long period of irrigation, the variation of total nitrogen in soil was gradually reduced. The maximum content of lead ion in soil layer in 5 ~ 10cm soil layer is 62.39mg. Kg-1, and the minimum content in the 40~60 soil layer is 45.63mg. Kg-1.. The result shows that the lead ion content in the upper layer soil is greater than that of the bottom lead ion, the reason may be that the reed is less absorbed on the surface lead ion and makes a large amount of lead ion in the table. The results show that the content of lead ions in the soil increases with the increase of the time of the wastewater irrigation. The amount of lead ions in the soil increases significantly. The minimum copper ion content in the bottom soil is 12.53mg. Kg-1. The copper ions in the waste water are enriched in the upper layer of the soil because of the adsorption of soil particles; A large amount of cadmium ions are enriched in the middle and bottom layers of the soil, and the content of cadmium ions in the surface soil is relatively small. The maximum amount of cadmium ion in the surface layer is 2.00mg. Kg-1., the content of chromium ions is enriched in the surface layer of 53.76mg. Kg-1, indicating that the absorption of chromium ions in the surface soil is less. It is obvious that the content of the manganese ion is more than the content of the bottom manganese ion. It shows that the amount of manganese ions in the soil is distributed in different soil layers and is more distributed in the middle and lower layers, and the content of zinc ion is not good to follow in the different soil layers. It is not the bottom or the surface, and the zinc ion is not the zinc ion. The content of the content is larger or smaller, and the variation of soil zinc ion is distributed in different soil layers. And with the increase of soil depth, the change is gradually reduced. (5) the content of lead ions in soil has the largest concentration of 300mg. L-1, and the concentration of lead ion is the largest, and the mass concentration is 50mg L-1 treatment. The content of lead ion in soil is the smallest. The highest content of lead ion in 5 ~ 10cm soil layer is 62.39mg kg-1.. The distribution of copper ions in each layer is similar. In the 5 ~ 10cm soil layer, the maximum copper ion content is 59.49mg. Kg-1. In the 40 ~ 60cm soil layer, the copper ion content is the largest in 45.28mg. Kg-1. maturity soil, which is the largest. The absorption of copper ions in the soil was weak after the irrigation of papermaking wastewater at maturity. The concentration of cadmium ion in the soil layer of 0 ~ 5cm soil was the highest in the soil layer of 300mg. L-1. The change amount of cadmium ion change at the mass concentration of 300mg. L-1 was the largest, the 50mg L-1 treatment was the smallest. The content of chromium ion in soil was in the 0 ~ 5cm soil layer. The higher the concentration of the irrigation wastewater, the more chromium ion content in the soil. The change of the chromium ion variation with the reed growth period is the emergence period of the jointing stage in the flowering stage of the mature period. The manganese ion content in the soil is the largest in the 0 ~ 10cm soil layer when the content of the soil is treated by the mass concentration of 300mg. L-1. Then, the content of manganese ions in the soil layer is from 40 to 60cm. The manganese ion content of soil layer is the smallest. The change of manganese ion is similar to that of manganese ion. The content of zinc ion in soil increases with the increase of irrigation quality. It has a significant correlation with the physical and chemical properties of soil.
【学位授予单位】：沈阳农业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S273.5;S151.9

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