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61.
为了了解阜蒙县畜禽养殖业的现状,掌握畜禽养殖业污染特点,对养殖业污染进行了监测,结果表明畜禽养殖造成了对大气和地下水的污染,于是对此提出了控制污染的对策。  相似文献   
62.
SUMMARY

Xishuangbanna in southwest China is a tropical and subtropical region with extraordinary traditional cultures and attractive landscapes. Rubber cultivation is a key production source undergoing rapid growth. It contributes substantially to improvement of the local economic situation and partially replaces traditional slash-and-burn agriculture in the uplands, but it also results in biodiversity loss and environmental degradation and disturbs the peaceful life of the indigenous people. We discuss the traditional ecological knowledge (TEK) preserved in daily practices and the present types of rubber plantations and suggest the application of TEK, in particular, the indigenous land-use experience to rubber cultivation, in order to promote sustainability in local economic development and ecological well-being.  相似文献   
63.
In this study, we investigate whether traditional swidden agriculture on nutrient-poor tropical soils can sustainably support a growing indigenous population within Manu National Park, Peru. Based on interviews with 50 Matsigenka farmers, as well as GPS mapping and field visits, we established the location and size of all 124 swidden gardens cultivated in 2000 and 2001. Using a GIS-based soil map of Manu Park, we identify the total extent of potential arable land (1) throughout the park zones currently available for Matsigenka habitation, and (2) within the vicinity of the two study communities. Taking into account current per capita garden size, cultivation and fallow practices, we calculate the maximum human carrying capacity of swidden agriculture for (1) all available park zones and (2) the immediate vicinity of the two current communities. Even given the second, highly limited scenario, the sustainable human carrying capacity is estimated to be 2,138 individuals, which is far higher than the current population of about 420 people. Thus, arable land does not appear to be a limiting factor for the growth of the indigenous population in Manu Park at the current time. Other possible limiting factors for population growth are identified and discussed. We conclude that a conservation policy of population stabilization around the current settlements is viable in that it will not result in reduced resource availability over the next few decades, and that the challenge is to identify and mitigate the forces causing population fissioning and spread. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
64.
昆明市规模化畜禽养殖场污染现状及控制对策   总被引:1,自引:0,他引:1  
对昆明市畜禽养殖污染现状调查显示,2002年规模化畜禽养殖场产生粪尿207290t,大部分被作为农家肥处理掉,平均使用率为85%,但几乎未经过无害化处理,对周围区域水体及湖泊造成严重污染.政府应对畜禽养殖业进行宏观监挖,加大环境管理力度,加强畜禽污水监测排放,并进行减量化治理,无害化处理,综合利用,循环发展,实现生态养殖.  相似文献   
65.
畜禽养殖废水的混合处理工艺   总被引:11,自引:1,他引:10  
针对畜禽养殖场废水的“三高”特点,即CODCr高、氨氮高、SS高,应用气浮ABRCASS湿地及生态塘为主体的废水处理工艺。结果证明,该工艺处理后的废水CODCr、氨氮、SS等指标都能达到(GB89781996)一级排放标准。  相似文献   
66.
资源型城市可持续竞争力的培育--以山西省大同市为例   总被引:1,自引:0,他引:1  
首先对我国资源型城市的倒“U”型发展现象进行解析,接着分析了我国资源型城市存在的主要问题,并对资源型城市的可持续竞争力构建进行了概述,然后通过案例分析的方式,分析了资源型城市在同等规模城市中的可持续竞争能力。最后根据资源型城市的类型分别提出了培育其城市可持续竞争力的对策。  相似文献   
67.
城市污水厂污泥替代营养盐培养海水小球藻的研究   总被引:3,自引:0,他引:3  
张聪  谢爽  孟范平 《环境工程学报》2010,4(5):1186-1190
为了城市污水厂污泥的资源化利用,对污泥替代F/2培养基培养海水小球藻(Chlorella pacifica)进行了研究。首先采用研磨-离心法制备污泥抽提液,将其与F/2培养基按体积比7∶3混合,接种微藻并在优化的条件下培养6 d,逐日测定混合液中无机氮、磷的浓度,培养结束后测定微藻生物量以及干藻中蛋白质、氨基酸和重金属含量。结果表明,将微藻在最佳条件下培养6 d后,混合液中PO34--P、NO2--N、NH4+-N和NO3--N的吸收率分别达到97.32%、96.72%、97.55%和78.13%;与F/2培养基对照组相比,混合液中微藻的生物量增加11.5%;蛋白质、必需氨基酸和非必需氨基酸的含量变化不大。另外,干藻中的重金属含量符合饲料行业标准的要求。  相似文献   
68.
采用上流式固定床反应器,在常温下连续运行,考察MnO2对海洋性ANAMMOX菌富集培养的影响,其中接种的海洋海底沉积物采自大连市附近海域。结果表明,在反应器运行近150 d中,加入MnO2的R1反应器的最大总氮去除速率为137.82 g N/(m3·d),比没有加入MnO2的R2反应器高出近20 g N/(m3·d)。在低温环境(10~15℃)运行时,R1反应器的氨氮和亚硝氮去除率比R2反应器均高出10%,且R1反应器对温度变化的适应性和运行稳定性都好于R2反应器。这表明MnO2的加入确实在一定程度上促进了海洋性ANAMMOX细菌的富集,并增强了ANAMMOX反应器对温度变化的适应性,使其能够在较宽的温度范围下运行。  相似文献   
69.
In this study, the effects of tetracycline exposure on wheat growth and the microbial community structure in the rhizosphere were investigated under hydroponic culture conditions. Exposure to various concentrations of tetracycline resulted in significant suppression of the growth of wheat roots and shoots, with minimum doses of 0.8 mg L?1 and 4 mg L?1 resulting in inhibition rates of 32% and 15.4%, respectively. Complete inhibition of the growth of these two parts of wheat plants was observed in response to treatment with tetracycline at 20 mg L?1 and 100 mg L?1, respectively. However, the germination of wheat seeds was not sensitive to exposure to tetracycline. The effects of tetracycline exposure on the microbial community in the wheat rhizosphere were evaluated through traditional cultivation and molecular biological analyses. The cultivation results indicated that bacteria were the dominant population, being present in concentrations of 1× 108–2.45× 109CFUs mL?1, although 39% to 87% inhibition occurred in response to tetracycline. The concentration of fungi increased in all tetracycline treated samples to 2.5 to 15.8 times that of the control. The highest concentration of fungi (4.27× 108 CFU mL?1) was observed in response to 60 mg L?1 tetracycline after 15 days of cultivation. In this stage, a large amount of fungal colonies was observed on the surface of the culture solution, the wheat roots became rotted and the plants became atrophic or even died. Molecular biological analysis indicated that the bacterial community structure was significantly different in samples that were exposed to high levels of tetracycline (over 20 mg L?1) than in samples that were exposed to lower concentrations. As the concentration of tetracycline increased, the diversity of the bacteria decreased. Additionally, several dominant sensitive species such as Sphingobacterium multivorum were suppressed by tetracycline, while some resistant species such as Acinetobacter sp. appeared or were conserved. The bacteria population tended to stabilize when the drug concentration exceeded 40 mg L?1.  相似文献   
70.
以厌氧颗粒污泥为接种污泥,采用味精生产废水进行培养,在SBR中以逐渐降低污泥沉淀时间的方法成功培养出好氧颗粒污泥。实验结果表明:污泥接种65 d后,出现细小的好氧颗粒污泥,呈黄褐色,95 d后颗粒污泥趋于成熟,粒径达0.6 mm左右,且周围存在大量原生动物;运行95 d后MLSS提高至8.00 g/L,SVI降至30.00 mL/g左右;成熟后的好氧颗粒污泥对味精生产废水中的COD和NH3-N具有良好的去除效果,出水COD和ρ(NH3-N)分别为80 mg/L和2 mg/L左右。  相似文献   
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