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61.
在滇池湖滨带核心区退塘还湖措施的基础上,通过对福保村湖滨废弃鱼塘改造,建立了表面流人工湿地系统,对该区域内面源污水处理进行了研究。研究表明,系统年削减人湖污染物COD、TN、TP负荷分别达7840、650和20kg,单位面积削减量分别为4704、390和12kg·hm^-2,削减率分别为28.02%、35.93%和4.86%;系统对污水中COD、NH3-N、TN、TP的去除率分别为15.57%、56.76%、40.37%和35.64%,且除COD外,旱季污染物去除率高于雨季;推流曝气可提高系统对污染物的去除效果,使NH3-N、TN、TP的去除率分别提高约39%、23%和21%,而COD去除率变化不明显。该系统为滇池湖滨区退塘还湖和湖滨生态系统重建提供了重要的技术示范,对滇池富营养化防治工作的开展具有重要意义。 相似文献
62.
组合家庭人工湿地系统处理北方农村生活污水 总被引:13,自引:5,他引:8
该文对组合家庭人工湿地系统处理北方农村生活污水进行了为期10个月的试验研究(包括冬季)。湿地床上部铺设了0.5 m的生物质保温层,使在冬季最低气温-15℃的低温下,系统温度仍维持在7℃以上,保证了系统的正常运行。结果表明,化学需氧量(CODcr)、生化需氧量(BOD5)、氨氮(NH3-N)、总磷(TP)、总固体悬浮物(TSS)和浊度的平均去除率分别为93.0%、96.0%、88.4%、87.7%、97.0%和89.6%,出水体积质量平均值分别为36.0、11.8、3.5、0.6、3.8 mg/L和浊度9.1 NTU,满足国家排放二级标准。组合家庭人工湿地系统是一种适合农村分散式家庭污水处理的新途径。 相似文献
63.
Cinzia Fissore Christian P. Giardina Carl C. Trettin 《Soil biology & biochemistry》2009,41(3):458-466
Forested mineral soil wetlands (FMSW) store large stocks of soil organic carbon (SOC), but little is known on: (i) whether the quality of SOC stored in these soils (proportion of active versus more resistant SOC compounds) differs from SOC in upland soils; (ii) how the quality of SOC in FMSW varies with mean annual temperature (MAT); and (iii) whether SOC decomposition rates in these environments respond to warming and drying more strongly than those observed in upland soils. To address this substantial knowledge gap, we identified nine FMSW and fifteen paired upland forest sites across three bioregions in North America (sub-alpine in Colorado; north-temperate in Minnesota; and south-temperate in South Carolina) to test the following three hypotheses. First, FMSW store a higher proportion of active SOC compared with upland systems because long anaerobic periods favor the accumulation of labile substrates. Second, in FMSW, SOC quality decreases from cold to warm bioregions because high quality detritus accumulates preferentially at cool sites where decomposition is slow. Finally, decomposition of SOC in FMSW will respond more strongly to warming under aerobic conditions than SOC from upland forest soils because of higher accumulation of active SOC in FMSW. To test these hypotheses, we incubated FMSW and upland forest soils at two constant temperatures (10 and 30 °C) for 525-d under aerobic conditions and constant moisture. In contrast to our first hypothesis, we observed similarly rapid depletion of active SOC compounds at initial stages of incubation across FMSW and upland sites, and across the 525-d incubations we observed overall lower SOC decomposition rates in our FMSW soils. In line with our second hypothesis, and across FMWS and upland soils, we found greater SOC loss in the sub-alpine bioregion than both temperate regions. In contrast to our last hypothesis, we found no difference in the temperature sensitivity (Q10) of SOC decomposition in FMSW and upland forest soils. Critically, total SOC loss (g SOC per g soil) was larger in FMSW because of the large amount of SOC stored in these ecosystems, indicating that despite a lack of difference between FMSW and upland responses, the total release of C from FMSW that could result from global warming may be large. 相似文献
64.
65.
The high grade gray water was pre treated by biologic contact oxidation on load of 0.72 KgBOD5·m-3·d-1, and then post treated by constructed wetland. On the basis of experiment, it was found that: Totle nitrogen (TN) was the restrictive index of the combinational technique. To meet the reclaimed water quality standard and reuse for waterscape, the peak hydraulic load of constructed wetland was 0.50 m·d-1 in summer (30~36 ℃), and 0.33 m·d-1 in winter (8~12 ℃). And the load ratio of the peak hydraulic under the summer and winter conditions was 3:2. With the experimental results and reclaimed water quantity requirements in different seasons of buildings, treatment scale can be determined. 相似文献
66.
67.
城镇生活小区污水生态原位净化回用处理工艺研究 总被引:2,自引:0,他引:2
研究设计了1种城镇生活小区污水生态原位净化回用处理工艺。经过试验分析证明:该工艺将厌氧生化技术和人工湿地技术进行有机结合,不仅可以大幅提高生物降解效率,可以使污水净化质量显著改善,可作为中水回用,还可以能满足小区生态环境和景观文化功能要求。与城镇污水集中处理回用相比,城镇生活小区污水生态原位处理回用更加经济合理。 相似文献
68.
升流式厌氧生物滤池与温室型人工湿地组合对农村生活污水处理的研究 总被引:1,自引:0,他引:1
针对中国农村分布分散、资金短缺,缺乏污水处理专业人员,而农村污水处理又是亟待解决的环境问题这一现状,笔者研究升流式厌氧生物滤池(UAF)与温室型人工湿地组合工艺低气温下处理农村生活污水的运行特点及效果。结果表明:UAF的最佳水力停留时间(HRT)为12 h,容积负荷0.632~0.936 kg/(m3?d),COD的平均去除率为56%,室外气温在-5~10℃(冬春),温室型人工湿地的最佳HRT为3天,组合工艺COD总去除率平均为75%,BOD5总去除率平均达到84%,SS总去除率平均不低于93%,氨氮总去除率平均为63%,TP总去除率平均为46%,出水水质除TP外均满足GB 18918-2002《城镇污水处理厂污染物排放标准》1级B标准。该工艺具有低能耗、低投资、低运行费用、运行维护简单等优点,适合作为农村生活污水的处理工艺推广使用。 相似文献
69.
Competitive traits of the invasive grass Arundo donax are enhanced by carbon dioxide and nitrogen enrichment
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Increased atmospheric carbon dioxide (CO2) and soil nitrogen (N) may confer competitive advantages to invasive species over native plant species. We conducted a two‐way factorial experiment, growing the model invasive plant Arundo donax in CO2 growth chambers to test how CO2 and N availability interact to affect plant growth and biomass allocation. CO2 was supplied at c. 400 mg L?1 and c. 750 mg L?1. N was supplied as ammonium nitrate at 640, 320 and 80 mg L?1. We hypothesised that the fertilisation effect of CO2 enrichment would offset limitations from N deficiency. The results indicated that A. donax plants grown with enriched CO2 and abundant N accumulated approximately 50–100% more biomass and allocated approximately 50% more biomass to rhizomes than plants grown under ambient CO2 conditions. Neither treatment affected the leaf area per unit mass (specific leaf area; SLA). Greater growth will likely increase A. donax's competitive potential, because increased rhizome biomass has been associated with increased stress tolerance and post‐disturbance resprouting capacity. The consistent SLA under all treatments suggests that A. donax has a morphological strategy that prioritises increasing leaf quantity over increasing individual leaves' photosynthetic potential. These results reveal the ecological strategies that contribute to the successful establishment, dominance and persistence of this invasive plant species. 相似文献
70.
2014年4~5月,在四川省西昌市邛海湿地的梦里水乡、焦家村-月亮湾、烟雨鹭洲、小渔村等区域选取了60个10 m×10 m黑水鸡(Gallinula chloropus L.)利用样方进行植被类型、明水面、水深、人为干扰距离、草本植物高度、草本植物密度、乔木距离、食物丰富度8个生态因子的生境选择分析。结果表明,黑水鸡喜植被茂盛、密度大、高度适中的隐蔽生境;就食物而言,黑水鸡尤喜水浅且食物丰富的水域,对明水面的选择不明显;干扰因素研究表明,人为活动对黑水鸡的影响不大,而人为活动稀少区域的黑水鸡对干扰稍显敏感。主成分分析结果显示,影响黑水鸡春季生境选择的因素主要有隐蔽性、食物多寡以及干扰程度。 相似文献