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311.
The resilience of Australia's food-supply chain following natural disasters has been brought into question, following the significant flooding and cyclone events of 2010/2011. How this manifests at the community level, in both rural and urban locations, has been examined through the lens of large and small food retailers in northern NSW. These interviews reveal the fragility of both the long and short supply chain where transport systems are compromised. Self-imposed standards severely restricted the ability of supermarkets to acquire fresh food, in the face of transport disruptions. Similarly, the precarious position of rural food retailers, exposed to continual fuel and electricity price increases, is compounded by the impact of extreme weather events. The insights captured through this study suggest interception points, or policy entry points, to address the resilience of the food-supply chain.  相似文献   
312.
微量金属强化餐厨垃圾厌氧消化优化条件研究   总被引:1,自引:0,他引:1  
采用L9(34)正交试验,研究了CoCl2·6H2O、FeCl2 ·4H2O及NiCl2·6H2O投加量对餐厨垃圾厌氧消化总固体(TS)、挥发性固体(VS)和COD减量及累积产气量的影响,确定了三因素的主次顺序及最优工艺条件.结果表明,当CoCl2·6H2O、FeCl2·4H2O及NiCl2·6H2O的投加量分别为0.1 mg/(L·d)、1 mg/(L·d)和0.4 mg/(L·d)时,餐厨垃圾厌氧消化减量及产气效果均最优.在此条件下,经过25 d单相厌氧消化,餐厨垃圾厌氧消化TS、VS、COD的去除率及累积产气量分别达到46.04%、61.02%、58.24%和27 433 mL/L,比不投加微量金属的处理分别高16.98%、28.12%、27.84%和48.63%.Co、Fe和Ni的投加量对餐厨垃圾厌氧消化TS、VS和COD去除率及累积产气量均有显著影响,其中Co的影响达到极显著水平;Co、Fe和Ni对餐厨垃圾厌氧消化减量及产气效率影响的主次顺序及显著性从大到小均为Co、Ni、Fe.  相似文献   
313.
以餐厨垃圾为研究对象,在高温(55±1)℃条件下,采用连续湿式厌氧发酵技术研究发酵过程中进料有机负荷、日产气量、pH值、挥发性有机酸(VFA)质量浓度等参数的变化情况及相互作用关系.结果表明:厌氧消化过程中出现了4个阶段,即适应阶段、提高阶段、稳定阶段和超负荷阶段;反应达到稳定阶段时,反应器运行有机负荷为3.9 kg/(m3·d),系统pH值稳定在7.8左右,平均产气速率达到5.26L/d;负荷达到4.2 kg/(m3·d)时,对系统产生明显抑制作用.  相似文献   
314.
While claims about the environmental benefits of community gardens abound, few researchers have systematically assessed the ecological integrity of gardening practices. This study investigated gardening practices in 50 community gardens in Brisbane and Gold Coast cities, Australia. The study aimed to better understand how gardening practices might affect the ecological viability of community gardens. Factors investigated included: garden bio-physical characteristics, operators’ motivations, gardeners’ socio-demographic backgrounds, garden facilities and types of plants grown. Two broad types of gardens were identified: permaculture (21 gardens) and non-permaculture (29 gardens). Permaculture gardens used lower-impact gardening practices. Findings have policy implications for environmental planning and management.  相似文献   
315.
To better understand the diversity of metal resistance genetic determinant from microbes that survived atmetal tailings in northwest of China, a highly elevated level of heavymetal containing region, genomic analyses was conducted using genome sequence of three native metal-resistant plant growth promoting bacteria (PGPB). It shows that: Mesorhizobium amorphae CCNWGS0123 contains metal transporters from P-type ATPase, CDF (Cation Diffusion Facilitator), HupE/UreJ and CHR (chromate ion transporter) family involved in copper, zinc, nickel as well as chromate resistance and homeostasis. Meanwhile, the putative CopA/CueO system is expected to mediate copper resistance in Sinorhizobium meliloti CCNWSX0020 while ZntA transporter, assisted with putative CzcD, determines zinc tolerance in Agrobacterium tumefaciens CCNWGS0286. The greenhouse experiment provides the consistent evidence of the plant growth promoting effects of these microbes on their hosts by nitrogen fixation and/or indoleacetic acid (IAA) secretion, indicating a potential in-site phytoremediation usage in themining tailing regions of China.  相似文献   
316.
An alternating mesophilic and thermophilic two stage anaerobic digestion(AD) process was conducted. The temperature of the acidogenic(A) and methanogenic(M) reactors was controlled as follows: System 1(S1) mesophilic A-mesophilic M;(S2) mesophilic A-thermophilic M; and(S3)thermophilic A-mesophilic M. Initially, the AD reactor was acclimatized and inoculated with digester sludge. Food waste was added with the soluble chemical oxygen demand(SCOD) concentrations of41.4–47.0 g/L and volatile fatty acids of 2.0–3.2 g/L. Based on the results, the highest total chemical oxygen demand removal(86.6%) was recorded in S2 while S3 exhibited the highest SCOD removal(96.6%). Comparing S1 with S2, total solids removal increased by 0.5%; S3 on the other hand decreased by 0.1 % as compared to S1. However, volatile solids(VS) removal in S1, S2, and S3was 78.5%, 81.7%, and 79.2%, respectively. S2 also exhibited the highest CH4 content, yield, and production rate of 70.7%, 0.44 L CH4/g VSadded, and 1.23 L CH4/(L·day), respectively. Bacterial community structure revealed that the richness, diversity, evenness, and dominance of S2 were high except for the archaeal community. The terminal restriction fragments dendrogram also revealed that the microbial community of the acidogenic and methanogenic reactors in S2 was distinct. Therefore,S2 was the best among the systems for the operation of two-stage AD of food waste in terms of CH4production, nutrient removal, and microbial community structure.  相似文献   
317.
文章介绍了南充炼油化工总厂循环水场循环水系统管理及处理技术现状,在与其他炼厂循环水处理状况分析比较的基础上,剖析了该厂循环水系统存在的问题,并就改善水系统、水冷设施和改进水处理技术、加大监测力度等方面进行了探讨,为炼油厂实现循环水全面达标、确保生产装置"安、稳、长、满、优"运行提供了参考。  相似文献   
318.
319.
中国有机食品开发及农业产业化   总被引:2,自引:0,他引:2  
本文简要介绍了有机食品和农业产业化的基本概念,分析了二者间的统一性,这对正确指导我国有机食品的开发有一定的现实意义。  相似文献   
320.
The fishing and hunting performed by inhabitants of the Extractive Reserve of the Upper Juruá, Acre, Brazil was studied, and an ecological analysis on the use of fish and game, including preferences, taboos and medicinal uses, and of fish abundance was made. Research was carried out at the Upper Juruá Extractive Reserve in three visits (1993 and 1994). A total of 143 individuals (101 families) living along the banks of the rivers Juruá, Tejo, Bagé, S. João and Breu were interviewed, and 115 species of fish with set gillnets were collected. Local economic activities included rubber-tapping and small-scale agriculture. Fishing was especially important in the dry season, when cast net and hook and line were used. Hunting and game consumption were intensive in the wet season. Some local rules may be useful as starting points for local management, such as the use of fish diversity through lake management, the use of water level seasonality, hunting periods or quotas, and food taboos. The integration of academic research with indigenous knowledge and demands is important to develop management plans which protect both biological and cultural diversity.  相似文献   
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