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1.
Landscapes fulfil a multitude of ecological and social functions. Due to the fact that both traditional and everyday landscapes today face many different threats, regulatory measures have been undertaken in many countries to protect and further sustainable landscape development. They include legislation as well as economic incentives. In recent years, however, it has become clear that just to have a few laws and to spend money on subsidies is not enough. Factors other than legislation are also essential to further the sustainable development of landscapes. One of the basic factors affecting the success or failure of landscape conservation measures is public acceptance of these measures. Our project took this as its starting point. The objective was to determine which conditions and factors influence acceptance positively or negatively. To this end 22 Swiss who are directly affected by nature conservation measures, in particular by mire landscape and dry meadow conservation measures, were interviewed using qualitative interview techniques. It is shown that perception, communication, and possibilities to participate are the most decisive driving factors influencing the formation of a long-lasting acceptance. Furthermore, acceptance may be based mainly on economic criteria, on usefulness, on ecological or even aesthetic aspects. It can be shown that not all of these motivations lead to a long-lasting acceptance. Ecologically based acceptance seems the most promising because it is founded on general convictions. Economic incentives--though important--seem to generate only superficial acceptance and do not seem to be as important as is usually assumed.  相似文献   
2.
The importance of wild edible herbaceous species to resource poor households in most rural economies within savannas has been little studied. This is because most of the herbs grow in impoverished species communities and lands, often referred to as 'marginal lands'. The aim of this paper is to conceptualize how the economics of wild edible herbs to households can be used to add value to total livelihoods and conservation within traditional communal areas of South Africa. Analysis of the economics of the consumption of wild edible herbs in Thorndale (Bushbuckridge district) of the Limpopo province is presented. The majority of households consumed wild edible herbs, averaging 15.4 kg dried weight per household per year and valued at $167 per household. The herbs were mostly harvested from uncultivated areas of farms, and rangelands. There was little correlation between household characteristics and the dependence on wild herbs for food. The local people noted a decline in the availability of the species, although not much is known about attempts to cultivate them. The only reasons attributed to the decline were nutrient poor soils and insufficient rains. With this background, developing a local strategy to sustain the species through cultivation by households was found to be feasible. A multiple-use system for the herbs, their improvement and value addition towards commercialization and increased household usage may result in wider acceptance and subsequent cultivation. Species diversity will be enhanced whilst conserving the land on which they grow. This multiple use system may include species roles in soil and water conservation.  相似文献   
3.
Heterotrophic cultivation caused high level of ROS and high lipids accumulation. HMTC is the best culture strategy for improving the microalgal biomass. Chlorella sp. HQ had great nutrient removal capacity under five culture strategies. The effects of cultivation strategies (including autotrophic cultivation (AC), heterotrophic cultivation (HC), fed-batch cultivation (FC), heterotrophic+ autotrophic two-stage cultivation (HATC), and heterotrophic+ mixotrophic two-stage cultivation (HMTC)) on the growth and lipid accumulation of Chlorella sp. HQ and its total nitrogen (TN) and total phosphorus (TP) removal in secondary effluent were investigated in column photoreactors. The results showed that the TN and TP removal rates ranged between 93.72%–95.82% and 92.73%–100%, respectively, under the five different strategies. The microalgal growth potential evaluated by the maximal growth rate (Rmax) was in the order of HMTC>HC>FC>AC>HATC. The values of biomass, total lipid yield, triacylglycerols (TAGs) yield, and total lipid content of the microalga cultivated in the last 5 d increased significantly, but the TAGs productivities of the five strategies were lower than those in the first 7 d. Compared with all the other cultivation strategies, the TAGs productivity and yield after 12 d of cultivation under the heterotrophic condition reached the highest values accompanying the highest level of intracellular reactive oxygen species (ROS), in which the TAGs yield reached 40.81 mg/L at the end of the cultivation period. The peaks in TAGs yield and ROS level suggested that HC was beneficial for lipids accumulation via regulating the cellular redox status and exerting ROS stress on microalgal cells. In summary, HMTC was the best cultivation strategy for improving the microalgal biomass and HC was the best strategy for microalgal TAGs accumulation to produce biodiesel.  相似文献   
4.
以沈阳市某污水处理厂普通絮状活性污泥为接种污泥,采用人工配制的模拟废水,在SBR反应器中进行好氧颗粒污泥培养实验研究。结果表明:通过运行方式的调整及参数的改变,在第33 d培养出成熟的好氧颗粒污泥,污泥粒径在2~3 mm左右;在一次曝气后增加静置缺氧段,有利于脱氮,系统中COD、NH3-N去除率可分别达到93%和92%;好氧颗粒污泥系统中含有大量的原生动物和后生动物,系统中污泥状态良好,处理效果好。采用逐步提高生活污水比例的方法对颗粒污泥进行驯化,当生活污水的比例达到100%时,系统出水COD50mg/L,NH3-N5 mg/L,达到GB18918—2002一级A出水标准。  相似文献   
5.
We tested predictions of the relative changes in plant leaf traits in response to land uses in Australian eucalypt grassy ecosystems. Predictions were determined from responses observed in European landscapes in relation to disturbances associated with agricultural land uses. We measured specific leaf area (SLA) and leaf dry matter content (LDMC) across five land uses: reference sites (closest to pre-European state), native pastures (unfertilized), fertilized pastures, sown pastures (cultivated and fertilized) and enriched grassland (previously fertilized, no longer grazed). Leaves were expected to have higher SLA and lower LMDC at sites with increasing fertility and/or disturbance.The predictions were confirmed, with SLA increasing progressively in land uses associated with (1) grazing; (2) grazing and fertilization; (3) grazing, fertilization and cultivation. Values for LDMC were closely (but inversely) correlated with those of SLA. For both traits, there were relationships with available soil phosphorus but not with soil total nitrogen. The positive correlation of SLA with phosphorus was not evident above 30 mg kg−1, the recommended level of phosphorus for improved pastures.Results confirm patterns of leaf-trait response to disturbance that reflect fundamental constraints to plant survival in habitats with different levels of resources and disturbances. A conservative strategy for low productivity undisturbed habitats is associated with low SLA and high dry matter content in contrast to fertile disturbed habitats which select for high SLA and low dry matter content. The changes in leaf traits across land uses resulted from species substitution rather than variation within species across sites, and most notably the replacement of native by annual exotic species as land use intensifies.Recommended fertilization rates for pasture production convert the ground layer to plants with soft, digestible leaves, that are responsive to fertilizer and desirable for livestock production. However, fertilization also drastically reduces the diversity of native plants and annual plants tend to dominate. The trade-off associated with high production includes increased vulnerability to soil erosion, due to reduced plant cover and low persistence of cover. If alternative ecosystem values such as erosion control, water quality, salinity control and biodiversity persistence are required, incentives may be needed to offset the loss of production that can be gained from fertilizer application.  相似文献   
6.
为了解平原河网地区农用化学物(化肥和农药)对地表水质的污染程度,调查了嘉兴市某农区在施肥和雨后,径流对地表水质的影响,初步揭示了水质与农时和降雨情况的关系。调查表明,农业非点源污染受农时、降雨的影响较大,其中农时的影响更大,施肥后短时间内水质即下降,变化非常显著。  相似文献   
7.
苯酚厌氧降解的厌氧污泥驯化方法研究   总被引:1,自引:0,他引:1  
在厌氧法处理含酚废水时,苯酚厌氧降解的厌氧污泥的培养与积累十分重要。本文通过混合厌氧污泥驯化、单一厌氧污泥驯化、好氧污泥转兼性驯化三组对比试验,探讨了合适的苯酚厌氧降解的厌氧污泥的驯化方法。研究表明:好氧污泥转兼性法驯化历时最短,处理效果好。静态培养时,微生物经过2个多月的驯化,日均降解苯酚的速率达100mg/(L·d)  相似文献   
8.
Cultivation theory research has found a relationship between heavier viewing of television and less concern about the natural environment. The current research delves further into this issue by exploring how environmentalists’ television viewing is related to their attitudes about the environment. The findings indicate that when overall television viewing is the independent variable, there are cultivation and mainstreaming effects for environmentalists (i.e., environmentalists who were heavy viewers of television scored lower on the new environmental paradigm (NEP) scale than lighter viewing environmentalists, and were more similar to the general public in their environmental attitudes than lighter viewers). The findings also show that the cultivation effects are related to need for cognition (NFC) and attention to television (such that those with higher NFC, and those who pay more attention to television, have lower scores on the NEP scale). When non-fiction programming is the independent variable, however, heavier television viewers score higher on the NEP, and NFC and attention to television do not relate to the cultivation effect.  相似文献   
9.
硝化细菌富集培养及处理富营养化水体应用研究   总被引:2,自引:0,他引:2  
通过对沈阳市北部污水处理厂曝气池的活性污泥进行培养,使污泥中异养细菌数量减少,硝化细菌数量增加,成为优势菌,并用此污泥处理富营养化水体,结果氨氮大幅度降低。  相似文献   
10.
林业是生态建设的主力军,是生态保护的重要载体。《森林培育技术》教学内容不能满足社会的需求,跟不上时代发展的需要,迫切需要改革。以就业导向等为原则,采取优化课程内容,突出实用性等措施,对高职生态环境保护专业的骨干课程《森林培育技术》的教学内容、教学方法、考试方法进行改革探索。  相似文献   
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