首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
The shade impact by Inga densiflora on water use and drainage in a coffee agroforestry system (AFS) was compared to coffee monoculture (MC) in Costa Rica. Rainfall interception, transpiration, runoff and soil water content were monitored during 3 years. Runoff was lower in AFS than MC (5.4 and 8.4% of total rainfall, respectively) and a higher water infiltration was observed under AFS. Still, the higher combined rainfall interception + transpiration of coffee and shade trees in AFS resulted in a lower drainage than in MC. No coffee water stress was recorded either in AFS or MC as relative extractable soil water remained above 20% during the dry seasons. Time course of soil water content showed enhanced access to soil water between 100 and 200 cm depth in AFS. This suggests complementarity for soil water between coffee and shade trees. The model HYDRUS 1D predicted that drainage at 200 cm depth accounted for a large fraction of annual rainfall (68% for MC and 62% for AFS). Climatic scenario simulations showed (1) a potential competition for water between coffee and shade trees when the dry season was extended by 4–6 weeks compared to actual, and (2) a severe reduction in annual drainage, but without competition for water when rainfall was reduced down to 40% of the actual.  相似文献   

2.
Arboreal ants form patchy spatial patterns in tropical agroforest canopies. Such patchy distributions more likely occur in disturbed habitats associated with lower ant diversity and resource availability than in forests. Yet, few studies have quantitatively examined these patchy patterns to statistically test if ants are non-randomly distributed or at what scale. Coffee agroecosystems form a gradient of management intensification along which vegetative complexity and ant diversity decline. Using field studies and a spatially explicit randomization model, I investigated ant patchiness in coffee agroecosystems in Chiapas, Mexico varying in management intensity to examine if: (1) coffee intensification affects occurrence of numerically dominant ants, (2) numerical dominants form statistically distinguishable single-species patches in coffee plants, (3) shade trees play a role in patch location, and (4) patch formation or size varies with management intensity. Coffee intensification correlated with lower occurrence frequency of numerically dominant species generally and of one of four taxa examined. All dominant ant species formed patches but only Azteca instabilis was patchy around shade trees. Ant patchiness did vary somewhat with spatial scale and with strata (within the coffee layer vs around shade trees). Patchiness, however, did not vary with management intensity. These results provide quantitative evidence that numerically dominant ants are patchy within the coffee layer at different scales and that shade tree location, but not coffee management intensity, may play a role in the formation of patchy distributions.  相似文献   

3.
The mountain chain of the Sierra Madre de Chiapas in southern Mexico is globally significant for its biodiversity and is one of the most important coffee production areas of Mexico. It provides water for several municipalities and its biosphere reserves are important tourist attractions. Much of the forest cover outside the core protected areas is in fact coffee grown under traditional forest shade. Unless this (agro)forest cover can be sustained, the biodiversity of the Sierra Madre and the environmental services it provides are at risk. We analyzed the threats to livelihoods and environment from climate change through crop suitability modeling based on downscaled climate scenarios for the period 2040 to 2069 (referred to as 2050s) and developed adaptation options through an expert workshop. Significant areas of forest and occasionally coffee are destroyed every year by wildfires, and this problem is bound to increase in a hotter and drier future climate. Widespread landslides and inundations, including on coffee farms, have recently been caused by hurricanes whose intensity is predicted to increase. A hotter climate with more irregular rainfall will be less favorable to the production of quality coffee and lower profitability may compel farmers to abandon shade coffee and expand other land uses of less biodiversity value, probably at the expense of forest. A comprehensive strategy to sustain the biodiversity, ecosystem services and livelihoods of the Sierra Madre in the face of climate change should include the promotion of biodiversity friendly coffee growing and processing practices including complex shade which can offer some hurricane protection and product diversification; payments for forest conservation and restoration from existing government programs complemented by private initiatives; diversification of income sources to mitigate risks associated with unstable environmental conditions and coffee markets; integrated fire management; development of markets that reward sustainable land use practices and forest conservation; crop insurance programs that are accessible to smallholders; and the strengthening of local capacity for adaptive resource management.  相似文献   

4.
Compared to the environmental and conservation value as refuges for biodiversity, less is known about the social and economic value of shaded coffee systems. The agroforestry system can serve as a source of non-coffee products for diverse purposes. This study focuses on the role of shade trees in smallholder coffee farms, examining the wood products derived from the shaded coffee system. Data presented from surveys with 185 growers in Peru and 153 growers in Guatemala show that the consumption and sale of all non-coffee products account for a fifth to a third of the total value realized from the agroforestry system. Fuelwood and construction materials account for much of this value. Differences seen between countries can be traced to agricultural intensification – the degree to which the coffee agroforestry system is “technified” (i.e., managed with a reduced shade tree cover and diversity, high-yielding cultivars, agrochemical inputs, etc.) – as well as the relative demand for wood resources and farmers’ access to natural forest systems.  相似文献   

5.
There are worldwide approximately 4.3 million coffee (Coffea arabica) producing smallholders generating a large share of tropical developing countries’ gross domestic product, notably in Central America. Their livelihoods and coffee production are facing major challenges due to projected climate change, requiring adaptation decisions that may range from changes in management practices to changes in crops or migration. Since management practices such as shade use and reforestation influence both climate vulnerability and carbon stocks in coffee, there may be synergies between climate change adaptation and mitigation that could make it advantageous to jointly pursue both objectives. In some cases, carbon accounting for mitigation actions might even be used to incentivize and subsidize adaptation actions. To assess potential synergies between climate change mitigation and adaptation in smallholder coffee production systems, we quantified (i) the potential of changes in coffee production and processing practices as well as other livelihood activities to reduce net greenhouse gas emissions, (ii) coffee farmers’ climate change vulnerability and need for adaptation, including the possibility of carbon markets subsidizing adaptation. We worked with smallholder organic coffee farmers in Northern Nicaragua, using workshops, interviews, farm visits and the Cool Farm Tool software to calculate greenhouse gas balances of coffee farms. From the 12 activities found to be relevant for adaptation, two showed strong and five showed modest synergies with mitigation. Afforestation of degraded areas with coffee agroforestry systems and boundary tree plantings resulted in the highest synergies between adaptation and mitigation. Financing possibilities for joint adaptation-mitigation activities could arise through carbon offsetting, carbon insetting, and carbon footprint reductions. Non-monetary benefits such as technical assistance and capacity building could be effective in promoting such synergies at low transaction costs.  相似文献   

6.
We studied the relationships of bird and small mammal species richness, composition, and abundance to vegetation structure and economic profitability across a coffee intensification gradient in central Veracruz, Mexico. We conducted 2 years of point count censuses for summer resident birds, 2 years of Sherman live trapping for small mammals, and gathered vegetation structure data at 147 sampling points distributed over 16 sites spanning a cultivation intensification gradient. We calculated net annual revenue per hectare as an index of profitability from economic and management data collected during interviews with plantation owners/managers. Both the species richness and abundance of forest-affiliated birds were significantly greater in floristically and structurally diverse ‘bajo monte’ coffee and forest compared with commercial polyculture coffee, which was, in turn, significantly richer than statistically indistinguishable specialized shade and sun coffee. Mammal capture rates were extremely low at all but two sites. Forest bird species richness and abundance were explained by multiple linear regression models that included statistically significant effects of shade cover, percent of trees with epiphytes, and canopy height. We found no clear relationship between profitability and biodiversity, with biodiverse bajo monte coffee plantations ranking among the most profitable under all price scenarios. The high profitability of biodiverse bajo monte coffee systems was not dependent on the inclusion of long-term environmental costs or premium pricing systems. Our results demonstrate that high-biodiversity coffee cultivation can be compatible with high profitability, and has significant potential for conserving biodiversity in coffee-growing regions, but only as a substitute for low-biodiversity coffee cultivation, not forest.  相似文献   

7.
After the reunion of North and South Vietnam in 1975, the area under small-holder, irrigated cultivation of Robusta coffee increased by a factor of 10 in the Central Highlands. The actual coffee acreage in Dak Lak province is estimated to be over 260,000 ha, representing 60% of the national production, with 405,000 t year−1 for the world market. Vietnam is presently the second largest exporter worldwide and expansion is still going on. In cooperation with the National Institute for Agricultural Planning and Projection (NIAPP), a 5-year development project “Land Evaluation for Land Use Planning and Development of Sustainable Agriculture in the Central Highlands of South Vietnam” was set up, with a goal of diagnosing the sustainability of the rapidly expanding Robusta coffee sector in Central Vietnam. This paper describes the reasons for this quick expansion and investigates the consequences in ecological and social terms. This is done based on a large-scale natural resources inventory, land suitability analysis for Robusta coffee and participatory rural appraisal combined with secondary statistical records from Dak Gan commune. It is representative of the Central Highlands in terms of geomorphological and pedological variability, ethnic identity and with regard to trade-offs between forest conservation and coffee expansion at the cost of available water stocks. Local institutional reforms in the eighties have accelerated coffee expansion in three ways: demographic resettlement, socio-economic liberalization and legislation towards land ownership. Interaction between these three factors has induced a second spontaneous migration flow towards the Highlands in the nineties. Forest area declined by 19% and was converted to coffee plantations, encouraged by the high economic return of this cash crop. The results indicate that this has happened in an haphazard manner and led to a mismatch between the present land use pattern and the natural resource base. Unsustainable land use manifests itself at four levels. (i) The areal limits for sustainable coffee production have been exceeded. (ii) As a consequence over 74% of the present coffee stand is situated on sub-optimal land units. (iii) An excessive coffee area in combination with over-irrigation is likely to deplete groundwater resources. (iv) And paradoxically 24.3% of suitable soils for coffee production is still under forest in Dak Gan. In turn this leads to large-scale environmental and socio-economic decline: soil erosion, water scarcity and social inequity resulting in conflicts between migrants and the indigenous tribes. Besides local reforms, world trade liberalization changed the global coffee market in the late nineties from a regulated system to a free trade market. This fostered global oversupply, which in combination with a stagnant coffee demand suppressed the world market price. Since Vietnam became the second world producer of Robusta, prices have declined by a factor of 3, not only affecting the local sector but households worldwide.  相似文献   

8.
This article draws lessons from a seven-year project on conservation and use of remaining coffee forests in the highlands of South-west Ethiopia. The project investigated the genetic diversity of Coffea arabica in its place of origin as well as economic perspectives of quality coffee marketing. With initially broad multidisciplinary natural and social sciences research a basis was laid for a second phase of praxis and implementation-oriented research in the same region.As a key innovative approach an NGO was established to take over all project management and implementation-oriented work in Ethiopia at the beginning of the second phase. This initiative helped decisively to solve the kind of problems identified in RESCUE (2012): ownership of results developed within R&D, the often missing mandate for science to actively contribute to solutions ‘on the ground’, and problems of cultural and social unsuitability and misunderstanding, which often are at the core of the problem when solutions from scientists are expected.The NGO operated as an intermediary between the involved scientists and other stakeholders from the coffee industry as well as from public administration and the Ethiopian polity. Its overall target was to contribute toward establishment of a biosphere reserve following the UNESCO MAB scheme and to use this scheme for the conservation and use of the remaining Ethiopian coffee forests. This target was achieved: the biosphere reserve has been accepted and accredited by UNESCO and is in operation. In addition, quality coffee from the development zones of the biosphere reserve is being sold on local markets in Yayu, SW Ethiopia.There are important lessons for the future of transdisciplinary and transformative sustainability science that can be drawn from this experience. These lessons concern concrete challenges and chances of research and development geared toward sustainable development:
  • •Working with implementation-targets as project organizing elements,
  • •communication and transfer of responsibility to involved stakeholders,
  • •challenges for praxis-oriented syntheses from research results,
  • •practical challenges of management and coordination for transdisciplinary projects, as well as.
  • •chances for long-term sustainability and use of research and implementation work.
These lessons are described in this article with the overall intention to draw conclusions and to make them more widely available for scientists and project coordinators working in transdisciplinary projects that aim to contribute toward (more) sustainable development.  相似文献   

9.
Agricultural development to meet rapidly growing demands for food and biofuel and the abandonment of traditional land use have had major impacts on biodiversity. Habitat diversity is one of the most important factors influencing biodiversity in agricultural landscapes. In this study we propose an ecological index of ecosystem or habitat diversity in agricultural landscapes – the Satoyama Index (SI) – that is discernible under appropriate spatial units (e.g., 6 km × 6 km) from 1 km × 1 km gridded land-cover data available from an open-access web site. A high SI value is an indicator of high habitat diversity, which is characteristic of traditional agricultural systems, including Japanese satoyama landscapes, while a low value indicates a monotonic habitat condition typical of extensive monoculture landscapes. The index correlated well with the spatial patterns of occurrence of a bird of prey (Butastur indicus) and species richness of amphibians and damselflies in Japan. The values of the SI also corresponded well to the spatial patterns of typical traditional agricultural landscapes with high conservation value in other countries, for example, the dehesas of the Iberian Peninsula and shade coffee landscapes in Central America. Globally, the pattern of East/South-East Asian paddy belts with their high index values contrasts markedly with the low values of the Eurasian, American, and Australian wheat or corn belts. The SI, which correlates landscapes with biodiversity through potential habitat availability, is highly promising for assessing and monitoring the status of biodiversity irrespective of scale.  相似文献   

10.
11.
Sustainable production and biodiversity conservation can be mutually supportive in providing multiple ecosystem services to farmers and society. This study aimed to determine the contribution of agroforestry systems, as tested by family farmers in the Brazilian Rainforest region since 1993, to tree biodiversity and evaluated farmers’ criteria for tree species selection. In addition, long-term effects on microclimatic temperature conditions for coffee production and chemical and biological soil characteristics at the field scale were compared to full-sun coffee systems. A floristic inventory of 8 agroforests and 4 reference forest sites identified 231 tree species in total. Seventy-eight percent of the tree species found in agroforests were native. The variation in species composition among agroforests contributed to a greater γ-diversity than α-diversity. Monthly average maximum temperatures were approximately 6 °C higher in full-sun coffee than in agroforests and forests. Total soil organic C, N mineralization and soil microbial activity were higher in forests than in coffee systems, whereas the chemical and biological soil quality in agroforests did not differ significantly from full-sun coffee after 13 years. Given its contribution to the conservation of biodiversity and its capacity to adapt coffee production to future climate change, coffee agroforestry offers a promising strategy for the area.  相似文献   

12.
The aim of this study was to examine the current coffee production and processing system in Costa Rica in order to maximize its sustainability through cost and risk reductions and identification of new opportunities. A two-year field investigation was performed for assessing resource, energy and water uses, characterizing by-products, and evaluating training, management and industry structure, with the aim of identifying opportunities for the implementation of Cleaner Production (CP) and industrial ecology (IE) strategies. The application of industrial ecology has been implemented in a piecemeal fashion and has not, therefore, been widely accepted by the industry at large. The broader coffee production system in Costa Rica does not encourage the practice of environmentally sustainable methods within production or processing, and does not encourage the exploration of niche markets that reward high-valued coffee in terms of quality or socio-environmental consciousness. Changes in industrial throughput, operational design, and management attitudes are needed to ensure sustainability within the industry. A number of opportunities for maximizing the sustainability of the coffee industry exist through: (a) strategic application of Cleaner Production, (b) effective use of resources, (c) alternative use of by-products, (d) efficient operational design, (e) training, (f) introduction of basic environmental management concepts, and (g) changes to industry structure. The paucity of data regarding research into the specific barriers to innovations within the coffee industry requires investigation. The specific barriers to the application of environmental innovations need to be identified and understood. This must include the social, cultural and institutional aspects governing the industry in addition to the technical and economic aspects normally addressed.  相似文献   

13.
The bean weevils Callosobruchus maculatus (F.) and C. rhodesianus (Pic.) both laid fewer eggs on previously infested adzuki beans than on fresh beans, even after eggs were removed. A variety of experimental treatments demonstrated the existence of an oviposition marker with ether soluble components. Callosobruchus rhodesianus was inhibited from ovipositing by the C. maculatus marker, but not vice versa.  相似文献   

14.
《Journal of Cleaner Production》2007,15(11-12):1032-1040
Replacing glass fibers with natural fibers in the automobile industry can yield economic, environmental and social benefits. This article evaluates the prospective environmental impacts of automobile applications of curauá fiber (Ananas erectifolius), which nearly equates the physical properties of glass fibers. The study identified economic and social advantages of applying curauá fiber composites in car parts. Besides costing 50% less than fiber glass, the use of curauá fibers can promote regional development in the Amazon region. In order to realize significant environmental benefits, however, the curauá-based composites would have to be lighter than their glass fiber-based counterparts.  相似文献   

15.
This paper aims to evaluate the environmental burdens associated with spray dried soluble coffee over its entire life cycle and compare it with drip filter coffee and capsule espresso coffee. It particularly aims to identify critical environmental issues and responsibilities along the whole life cycle chain of spray dried coffee. This life cycle assessment (LCA) specifically uses foreground data obtained directly from coffee manufacturers and suppliers. Aside from energy consumption and greenhouse gases emissions, water footprint is also studied in detail, including regionalization of water impacts based on the ecological scarcity method 2006. Other impact categories are screened using the IMPACT 2002+ impact assessment method.The overall LCA results for a 1 dl cup of spray dried soluble coffee amounts approximately to 1 MJ of primary non-renewable energy consumption, to emissions of 0.07 kg of CO2-eq, and between 3 and 10 l of non-turbined water use, depending on whether or not the coffee cultivation is irrigated and wet treated. When considering turbined water, use can be up to 400 l of water per cup. Pouch – and to a lesser extent metal can packaging alternatives – show lower environmental burdens than glass or sticks.On average, about one half of the environmental footprint occurs at a life cycle stage under the control of the coffee producer or its suppliers (i.e., during cultivation, treatment, processing, packaging up to distribution, along with advertising) and the other half at a stage controlled by the user (shopping, appliances manufacturing, use and waste disposal). Key environmental parameters of spray dried soluble coffee are the amount of extra water boiled and the efficiency of cup cleaning during use phase, whether the coffee is irrigated or not, as well as the type and amount of fertilizer used in the coffee field. The packaging contributes to 10% of the overall life cycle impacts.Compared to other coffee alternatives, spray dried soluble coffee uses less energy and has a lower environmental footprint than capsule espresso coffee or drip filter coffee, the latter having the highest environmental impacts on a per cup basis. This study shows that a broad LCA approach is needed to help industry to minimize the environmental burdens directly related to their products. Including all processes of the entire system is necessary i) to get a comprehensive environmental footprint of the product system with respect to sustainable production and consumption, ii) to share stakeholders responsibility along the entire product life cycle, and iii) to avoid problem shifting between different life cycle stages.  相似文献   

16.
As natural woodlands decline in both extent and quality worldwide, there is an increasing recognition of the biodiversity conservation value of production landscapes. In low-input, low-productivity grazing systems in Australia, the modification of natural woodlands through overstorey tree and woody regrowth removal are vegetation management options used by landholders to increase native grass production for livestock grazing; however, there is little empirical evidence to indicate at what tree densities biodiversity attributes are compromised. We examined the effects of overstorey tree density and understorey regowth on the floristic composition, stand structure and species richness of eucalypt woodlands in a grazing landscape in the Traprock region of southern Queensland, Australia. We sampled 47 sites stratified according to vegetation type (Eucalyptus crebra/Eucalyptus dealbata woodland; Eucalyptus melliodora/Eucalyptus microcarpa grassy woodland), density of mature trees (<6 trees/ha; 6–20 trees/ha; >20 trees/ha), and presence/absence of regrowth. Distinct patterns in composition were detected using indicator species analysis and non-metric multidimensional scaling, with low density areas compositionally indistinguishable, although distinct from other land management units. Within vegetation type, medium tree density woodlands were compositionally similar to high density and reference woodlands. Species richness ranged from 18 to 67 species per 500 m2 across all sites. No differences in total or native species richness were detected across management units; however, some differences in exotic species richness were detected. Differences in grass cover existed between low and high density management units, yet no difference in grass cover was evident between low and medium density management units. Our results suggest that medium tree densities may provide biodiversity benefits concordant with more natural areas, yet not adversely impact on pasture production. Retaining trees in grazing landscapes provides significant landscape heterogeneity and important refuges for species that may be largely excluded from open grassland habitats. Maintaining a medium density of overstorey trees in grazed paddocks can provide both production and biodiversity benefits.  相似文献   

17.
The lower tidal stretch of the river Ganges, known as Hugli (ca. 280 km), flows southward before entering the Bay of Bengal forming a vast mangrove-enriched estuarine delta called Sunderbans. Hugli estuary is a typical example of tide-dominated sink for contaminants from multifarious sources. This major important river is subjected to anthropogenic stress due to the socio-economic importance of these areas based on growth of industry, agriculture, aquaculture, port activities, fishing and tourism. The living resources have been degraded recently due to increases in population pressure, pollution and natural resource consumption to the extent of overexploitation. The present paper critically examines the physicochemical characteristics and level of dissolved heavy metals at three ecologically distinct zones along the course of the river – Babughat located in the eastern part of the metropolitan megacity Calcutta (140 km upstream from seaface), Diamond Harbor (70 km upstream from sea face) and Gangasagar positioned at the mouth of the Ganges estuary.Physicochemical characteristics of this partially mixed estuary are largely influenced by the interaction of seawater and discharge of riverine freshwater, annual precipitation and surface runoff. The levels of salinity, total dissolved solids, hardness and conductivity showed an increasing downward trend. Marked increase in biochemical oxygen demand (BOD) values (2.20–5.95 mg/l) was recorded in Babughat whereas correspondingly low values (0.75–2.82 mg/l) were noticed at Gangasagar. This can be attributed mainly due to huge organic load of untreated sewage from the twin city Howrah and Calcutta situated in the east and west of the river. Spatiotemporal distribution of heavy metals reveals a wide range of variations reflecting input of huge anthropogenic inputs associated with a number of physical and chemical processes. Levels of metals registered a seasonal pattern, with an increase during late monsoon months (September–October), a period characterized by low salinity and relatively low pH of the water. Elevated levels of dissolved Hg and Pb were also recorded in Babughat, with values ranging from 0.16 to 0.95 μg/ml and 0.017 to 0.076 μg/ml, respectively, this high values for Hg can be attributed to the discharge from pulp and paper manufacturing units and to atmospheric input and runoff of automobile emission for Pb.It was revealed that the socio-economic development of Calcutta, the most potential economic zone in India situated on the east bank of Hugli river, has had a significant impact on the water quality of this major river. The deterioration of water quality is directly related to nonfunctioning and malfunctioning of wastewater treatment plants and lack of environmental planning and coordination. To restore the ecological stability and economic vitality of this river, the following measures have been suggested: (i) strong vigilance programme is to be undertaken towards installation and maintenance of the wastewater treatment plants to check the flow of persistent contaminants in the river water and (ii) execution of legislation and mass awareness programmes are to be enacted to restore the sound health of the river. The authors urge that environmental education should be used as an effective tool for water resource management dealing with intricate and complex problems in the interaction between nature, technology and human beings.  相似文献   

18.
Vigna unguiculata (beans), Zea mays (maize) and Sorghum bicolor (sorghum) were grown with and without fertiliser in a savanna grassland (control) and under the effects of decomposing parts of eucalyptus in an old eucalyptus plantation with a well-lit floor (treatment).Morphological characters of the beans, compared between the two sites, showed that leaf dry-matter production, expressed as specific leaf area (SLA), did not differ between plants in the two sites (fertilised and unfertilised). Although the organic-matter content and water-holding capacity of the plantation soil were significantly higher than those of the control plants. beans, grain yield ha−1, shoot height, number of leaves and fruits were higher in the control plants. However, when beans were fertilised, shoot height did not differ between sites, but the other measured morphological characters and grain yield were significantly improved in both sites, although these characters still remained higher in the control. In maize and sorghum, grain yield ha−1 did not vary significantly in the two sites (fertilised or unfertilised). These findings suggest that beans can be incompatible with eucalypts, while maize and sorghum may be compatible with eucalypts for agrosilvicultural practices, and that fertilisation can offset, to an extent, the depressive effects of eucalypts on crops.  相似文献   

19.
The removal of the natural organic matter present in coffee processing wastewater through chemical coagulation-flocculation and advanced oxidation processes (AOP) had been studied. The effectiveness of the removal of natural organic matter using commercial flocculants and UV/H202, UV/O3 and UV/H2O2/O3 processes was determined under acidic conditions. For each of these processes, different operational conditions were explored to optimize the treatment efficiency of the coffee wastewater. Coffee wastewater is characterized by a high chemical oxygen demand (COD) and low total suspended solids. The outcomes of coffee wastewater treatment using coagulation-flocculation and photodegradation processes were assessed in terms of reduction of COD, color, and turbidity. It was found that a reduction in COD of 67% could be realized when the coffee wastewater was treated by chemical coagulation-flocculation with lime and coagulant T-1. When coffee wastewater was treated by coagulation-flocculation in combination with UV/H2O2, a COD reduction of 86% was achieved, although only after prolonged UV irradiation. Of the three advanced oxidation processes considered, UV/H2O2, UV/O3 and UV/H2O2/O3, we found that the treatment with UV/H2O2/O3 was the most effective, with an efficiency of color, turbidity and further COD removal of 87%, when applied to the flocculated coffee wastewater.  相似文献   

20.
Nicaragua is one of the four countries most affected by climate change, and coffee production is expected to vastly shrink in some critical areas. This can have considerable effects on social structure since nearly a third of its working population depend on coffee for a living. Social perceptions of climate change and water pressures are a key issue in the public's acceptance of adaptation measures. Furthermore, the existing risk for crop production is not necessarily correlated with the farmers’ awareness of that threat. This paper focuses on coffee producers’ perception of risk and adaptive capacity for coffee crops in Nicaragua in response to climate change and water availability. We aim to analyze how dependent the producers are on water resources, and if this reliance affects their perception of risk and their expectations with regard to public and private support for dealing with adaptation. A survey of 212 representative farmers of the national population of farms in the country's two most important production areas was conducted for this purpose. We consider socio-economic and biophysical variables to explain the farmers’ perceptions. Our findings show that experience and technical capacity are relevant to the adaptive capacity although smallholders do not always show high concern and their expectations with regard to external support are very low. The paper can be useful to prioritize the measures necessary for a greater level of involvement from stakeholders.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号