Water and nutrient use efficiency of a low-cost hydroponic greenhouse for a cucumber crop: An Australian case study   总被引：3，自引：0，他引：3  

Harsharn S. GrewalBasant Maheshwari  Sophie E. Parks 《Agricultural Water Management》2011,98(5):841-846

The Australian greenhouse industry is primarily dominated by low-cost hydroponic greenhouses for delivery of water and nutrients to plants to grow a variety of vegetable crops including cucumber and tomato. The nutrient rich drainage water from these greenhouses is generally released into the local environment causing pollution concerns. This study was initiated to investigate the opportunities in recycling drainage water to increase water and nutrient-use efficiency of hydroponic greenhouses and reduce the environmental impact of the drainage water discharge. Results indicated that a total of 4.15 ML/ha of irrigation water was applied during the 13 weeks crop growing period of which 2.56 ML/ha was drained off and 1.59 ML/ha was used to meet the crop evapotranspiration demand. The study showed that the recycling of the drainage water resulted in a 33% reduction in potable water used for irrigation in cucumber production. The drainage water contained 59% applied N, 25% applied P and 55% applied K and illustrated the potential for nutrient recovery and production cost savings through the reuse of drainage water. This case study demonstrates that some relatively simple changes in irrigation practices within greenhouse systems to recycle drainage water can considerably improve sustainability of low-cost hydroponic greenhouses and help minimise the environmental footprint of the greenhouse industry.  相似文献   

Soil salinity and sodicity effects of wastewater irrigation in South East Australia   总被引：1，自引：0，他引：1  

Zahida Muyen  Graham A. Moore 《Agricultural Water Management》2011,99(1):33-41

Although ‘sewage farming’ or wastewater irrigation started in Australia in the latter parts of the 19th century, it was in the late 1960s that a considerable interest was revived in arid and semi-arid parts of the world due to scarcity of alternative water sources and the urgency to increase local food production. The practice has manifold benefits in the form of water conservation, nutrient recycling, surface and ground water pollution prevention. But for arid and semi-arid regions like many parts of Australia, while wastewater irrigation can be an attractive solution to irrigation water problems, it might not be the ideal solution for the common soil types encountered in these regions. Due to characteristic low rainfall, high evaporation and low leaching, these soils tend to have higher salt accumulations. This paper examines the soil salinity and sodicity effects of wastewater irrigation in soil types typical to South Eastern Australia and takes the soils of Western Treatment Plant (WTP) as a case study to highlight these issues.  相似文献   

高寒冷凉地区食用菌菌糠再利用研究     

车海忠 《北方园艺》2011,(24):202-204

以双孢菇2796、鸡腿菇4号为试材,利用平菇、金针菇菌糠栽培双孢菇、鸡腿菇并进行羔羊育肥研究.结果表明:菌糠代粪肥栽培,双孢菇菌糠的添加量40％为最优;菌糠替代玉米芯或棉籽壳等生产主料栽培鸡腿菇添加20％～40％的菌糠和对照相比降低成本18％～35％,而产量仅下降9.6％～16.8％;菌糠饲料替代粗粮育肥羔羊菌糠添加20％育肥效果明显,增重率较对照高13.7％,毛体重较对照高3.2 kg,羔羊胴体重比对照组羔羊提高1.79 kg,屠宰率较对照提高2.2％.  相似文献   

用热管换热器回收密闭式鸡舍冬季换气中的余热   总被引：1，自引：2，他引：1  

袁小艳  李保明  俞宏军 《农业工程学报》2001,17(1):91-95

中国北方地区冬季气温低且冬季长，鸡舍结构上多采用密闭式以保温，使得冬季舍内空气质量恶化，须强制通风换气以保证空气质量，其结果使舍内气温降低。各种鸡舍在通风换气下舍温仅-2～3℃(东北地区舍温更低)，导致蛋鸡舍在冬季的生产性能下降5%～10%。由于冬季舍内排出的废气与补充的新风温差可达10～25℃，废气与新风还有湿度差，废气余热(包括显热和极少量的潜热)有一定的利用价值。为解决通风换气与保温这一对矛盾，该文提出将热管换热器用于回收密闭式鸡舍冬季排出废气中的余热。利用热管换热器可以将废气的50%以上余热回收以加热由舍外强制送入鸡舍的新风，以适当提高新风的温度。文中对热管换热器作了传热及阻力设计计算，对一定工况进行了参数优化并编制了通用程序。将热管换热器系统运用在鸡舍中运行，热管换热器实测热效率可达50%～65%，可节能、节省饲料 、提高产蛋率，有一定的推广价值。  相似文献   

生活污水对长春花生长及生理影响的研究     

胡宏友  卢昌义  叶勇  陈登雄 《中国生态农业学报》2005,13(4):131-134

利用不同稀释倍数的生活污水(污水∶清水,V/V,分别为1∶0;1∶1;1∶2;0∶1)浇灌长春花结果表明,与清水灌溉相比,污灌处理土壤NH4 -N含量由59.01mg/kg提高到64.22~65.89mg/kg,NO3--N含量由2.69mg/kg提高到3.03~4.54mg/kg,速效磷含量由32.29mg/kg提高到37.40~42.41mg/kg;增加了土壤酶活性,其中土壤过氧化氢酶、脲酶及蛋白酶活性分别比对照提高10.76%~23.32%、33.41%~103.69%和31.82%~131.82%;植物根系活性由170.25μg/g.h提高到177.88~471.69μg/g.h,叶绿素含量由1.78mg/dm2提高到2.68~2.98mg/dm2,植物干物质量由11.660g/盆提高到12.130~16.577g/盆。且以稀释1倍污水灌溉处理效果最佳。用原生生活污水直接灌溉虽降低污水肥效,造成土壤Cl-的积累,但对长春花生长及干物质积累无显著影响。  相似文献   

Variation of enzyme activities, CO2 evolution and redox potential in an Eutric Histosol irrigated with wastewater and tap water   总被引：1，自引：0，他引：1  

M. Brzezinska  S. C. Tiwari  Zofia Stepniewska  M. Nosalewicz  R. P. Bennicelli  A. Samborska 《Biology and Fertility of Soils》2006,43(1):131-135

An Eutric Histosol soil was irrigated for 4 years with municipal wastewater to compare its characteristics with a soil under natural rainfall that had never received wastewater and a soil that was irrigated with normal tap water. Four years irrigation of the soil with wastewater caused significant (P<0.001) increase in dehydrogenase, urease, acid and alkaline phosphate activities and CO₂ evolution, and reduced the redox potential (P<0.05). The influence of treatments and plant cover on soil properties were significant (P<0.05) under both salix and grasses, except for few properties (redox potential and urease and alkaline phosphatase activities). It is suggested that, although different toxicants, e.g. heavy metals, may accumulate in wastewater-treated soils, enrichment of soil with organic substances and nutrients stimulated CO₂ evolution and enzyme activities in the irrigated soil.  相似文献   

循环经济作用机理探讨   总被引：4，自引：2，他引：4  

任勇  吴玉萍  孙高峰 《中国生态农业学报》2005,13(4):1-3

从循环经济的内在本质、经济本质及其社会特征、核心作用和关键环节等角度,初步探讨了循环经济的作用机理。  相似文献   

高级氧化法处理腈纶厂废水的研究进展     

杨大壮  涂响  魏健  王培良  刘瑞霞 《安徽农业科学》2015,(23):236-238

介绍了腈纶厂废水的主要来源和危害,并综述了几种高级氧化法在处理腈纶废水、丙烯腈废水中的研究进展,同时分析了高级氧化法处理腈纶厂废水的作用机理、优势和存在的问题,并对其应用前景提出了展望。  相似文献   

一种共沉淀回收构建载体的新方法     

孔昆  陶园  朱宏波 《安徽农业科学》2015,(13):42-44

[目的]介绍一种新型的载体构建方法.[方法]利用乙醇可以使酶切反应中内切酶变性失活的特性对酶切产物进行回收和纯化,再将得到的混合沉淀溶解进行连接、转化.[结果]16～20 h长出单菌落进行PCR鉴定,转化后的单菌落有10％的阳性率,将阳性菌落提取质粒进行酶切鉴定,电泳条带正确,载体构建成功.[结论]利用产物混合回收方法成功构建了植物表达载体pCambia1301-cry3Aa,且省去酶切步骤,证明该方法是一种简便、实用的方法,具有一定的经济价值.  相似文献   

农药生产废水的综合治理     

王志东  吴浩  吴平 《农药科学与管理》2003,24(2):29-31

根据农药生产废水的特点，先采用物化处理，降低废水的CODcr浓度，提高废水可生化性，再进行双重生化处理。实践表明：采用此工艺，具有操作简单灵活，处理成本低，管理方便，出水水质高等特点。  相似文献