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1.
We introduce an approach for establishing reference conditions (RC) for rivers of the German Baltic Sea catchment, based on predictive modelling. An extensive data set of statistics from the year 1880 was coupled with literature data, providing a comprehensive basis for the calculation of regional historical nutrient emissions into rivers, river nutrient concentrations, and nutrient loading into the sea. Four different scenarios were calculated: scenario 1 assumed RC following previously established criteria for lakes (Poikane et al. in Environ Manag 45(6):1286–1298, 2010), scenario 4 applied the nutrient emission conditions of 1880 (considering non-intensive land usage, the presence of tile drainage systems, sewer systems, and the human population from 1880), and scenarios 2 and 3 considered intermediate conditions. Our results showed that nutrient emissions from scenario 1 accounted for approximately one-tenth of the currently observed total nitrogen (TN) and total phosphorus (TP) emissions. The nutrient emissions calculated for 1880 (scenario 4) were found to be 47 % (TN) and 55 % (TP) higher than those calculated considering reference lake conditions (scenario 1). Our results suggest that RC nutrient concentrations in rivers in the German Baltic Sea catchment were clearly below 0.05 mg/l for TP and 1 mg/l for TN. This range is in accordance with historical and calculated pristine nutrient concentrations from other rivers in similar catchments.  相似文献   

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Much current work on climate adaptation options vis-à-vis water management in rural sub-Saharan Africa has tended to focus more on technological and infrastructural alternatives and less on institutional alternatives. Yet, vulnerability to climate variability and change in these contexts is a function not just of biophysical outcomes but also of institutional factors that can vary significantly at relatively finer scales. This paper seeks to contribute towards closing this gap by examining institutional options for sustainable water management in rural SSA in the context of climate change and variability. It explores challenges for transforming water-related institutions and puts forward institutional alternatives towards adapting to increasingly complex conditions created by climate change and variability. The paper suggests revisiting the Integrated Water Resources Management approach which has dominated water institutional debates and reforms in Africa over the recent past, towards actively adopting resilience and adaptive management lenses in crafting water institutional development initiatives.  相似文献   

4.
We analyzed past and future trends in river export of dissolved nitrogen (N) and phosphorus (P) to the coastal waters of China, for a selection of rivers, as calculated by the Global NEWS models (Nutrient Export from WaterSheds). Over the period 1970–2000, river export of dissolved nutrients increased considerably, especially of dissolved inorganic N and P. Anthropogenic sources of N and P in rivers have become increasingly important, in particular N and P losses from agriculture. We tested the sensitivity of calculated nutrient export by rivers to changes in selected controlling factors. The calculated export of dissolved N and P is sensitive to changes in hydrology, synthetic fertilizer use and manure excretion in river basins. Changes in sewage inputs have large effects on dissolved inorganic P export. We analyzed future trends up to 2050 for several scenarios to illustrate the combined effects of selected management options. In the Base Scenario, the N and P export by the selected rivers increases considerably between 2000 and 2030. The increase continues from 2030 to 2050 except for DIP. Strategies to reduce N and P export by rivers include changes in agriculture, sewage and energy use. Changes in agriculture have the largest impact on future dissolved N and P river export to the coastal waters of China. The effectiveness of reduction strategies differs between nutrient forms and basins.  相似文献   

5.

When performed without technical criteria, the rapid expansion of irrigated agricultural frontiers can result in overexploitation of water, causing worrying impacts on the balance of agroecosystems. This study proposes a model applied to the state of Bahia, to estimate the water demand of areas irrigated by a central pivot, in order to contribute to information that will subsidize the inspection and planning of water resources in the promotion of sustainable agriculture. The irrigated areas were identified and measured by photointerpretation using orbital images from the Landsat-8 satellite. With a historical series of data, the reference evapotranspiration was calculated and monthly water balance was elaborated. The data obtained were spatialized by kriging, and with punctual values of water deficit (mm), the water demand of the irrigated perimeter of the equipment was estimated. The results were described considering strategic planning units, proposed from municipalities, hydrographic basins and biomes. A total of 4075 pivots were quantified, covering an irrigated area of 265,896.30 ha and with an average annual consumption of 1,333,473,208.02 m3 of water. Areas of high demand were identified, especially in the western region of Bahia, which includes the hydrographic basin of the São Francisco River and the Cerrado biome, concentrating 80.85% and 75.47% of the state water demand for pivots, respectively. Considering possible points of water vulnerability and continuity of this expansion, the results provide the primary information needed to encourage the adoption of public policies aimed at the management of water resources. The study method proposes guidelines that condition the application in any region of interest in the world.

Graphical abstract
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6.
Environment, Development and Sustainability - Realisation of the sustainable development goals (SDGs) will provide improvements to people's lives and longevity of the planet. The architectural,...  相似文献   

7.
A combined approach utilizing GIS, Participatory Rural Appraisal (PRA) and Focus Group Discussion (FGD) has been developed for resource mapping in a rural poverty-prone area of Bangladesh. This model integrated GIS and participatory tools to include the voices of the stakeholders in assessing available resources and needs. The resource mapping framework, developed using PRA with local community people and community gatekeepers, was aimed at sustainable resource management, and ArcView GIS was used to digitize the resource maps as a Decision Support System (DSS). A detailed assessment and analysis of the quality, quantity and physical status of resources was first mapped in the field and then digitized using GIS. FGD-based interaction with community people at each union in a subdistrict of Bangladesh revealed stakeholders’ opinions on land and water body management. The present paper demonstrates the power of this model as a policy-making tool for sustainable development and poverty eradication. It also recognized the need for collaboration between interdisciplinary policy planners and researchers to develop and implement a policy on agricultural resource management for poverty-prone areas.  相似文献   

8.
Society needs to adapt in order to provide the wealth that an increasing part of the world population is getting used to. We are on a track to ecological and resource collapse if actions are not taken soon. Technology will have to play a key role in the process of changing industrial society. But innovation has to be embedded in social and organizational innovation. We need sociotechnical change. Environmentally conscious design has been practiced in engineering design for more than a decade. Its merits are sometimes blamed as futile, as the world has not witnessed a significant contribution to the solution of the larger (global) problems. This paper first sketches a scheme of the various levels of technological change, ranging from: (1) incremental optimizations of single artifacts, to (2) major change of artifacts, (3) systems change, and (4) technological transitions (involving changes in production and consumption). It outlines the stakeholders involved in these types of innovations and the parties that could orchestrate the innovation process. In this paper, It is argued that the most encompassing level of technological innovation, the level of transition, is crucial for achieving long-term sustainable development, as it has the largest potential for improvement. However, transition is not very well manageable. The paper contains a review of the literature regarding the occurrence of technological transitions. After a transition has occurred, the new system is often not efficient. Its gains in terms of diminished resource consumption or pollution have to be enlarged by less encompassing innovation strategies, such as systems innovations and product optimization. Transitions for sustainable development are often impossible, as the new systems have to compete with fully developed and optimized systems that have far advanced at the learning curve, i.e., are optimized by various systems and incremental innovations. Less encompassing levels of innovation, even those that aim at more sustainability, can counteract transitions that have more potential for sustainable development by improving the competing (unsustainable) technology. The paper will give several examples of this dilemma and some guidelines for developing government policies as well as corporate strategies. On the policy level, it is argued that it is especially important to develop (scope for) market niches for new sustainable systems and products as they create scope for experiments that could lead to transitions.
Karel F. MulderEmail:
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9.
The coastal zone of the inner Thermaikos Gulf has been influenced by eutrophication during the past decades. The conditions of the catchment area-coastal zone continuum are assessed under the holistic Driver-Pressure-State-Impact-Response (DPSIR) framework. Major socioeconomic drivers, such as industrial and agricultural development as well as urbanization, exert substantial environmental pressures on the Axios River and the Thermaikos Gulf. The Thermaikos Gulf is a highly complex system, being affected by nutrient inputs from four rivers and the City of Thessaloniki. Moreover, the Axios River which is the most significant contributor of freshwater and nutrients to the gulf, is a transboundary river shared between Greece and the Former Yugoslav Republic of Macedonia (FYROM). The two countries have not yet established a mutual management plan to control freshwater and nutrient discharges. Long-term analysis has shown that presently, more than 11,800 t of nitrogen and 3,400 t of phosphorous are released annually into the marine system. In the Antropocene era, and particularly during the past 20 years, freshwater discharges have decreased and riverine nutrients have increased, whereas inputs from domestic and industrial effluents have a decreasing trend. However, nutrient over-enrichment impacts, i.e. eutrophication, harmful algal blooms and hypoxia still have to be addressed in order to identify whether the coastal system is recovering, or whether further actions should be undertaken to control nutrient inputs from the Axios River and/or other sources. Response actions, such as the improvement of Thessalonikis wastewater treatment plant, have proved to play a positive role in the reduction of domestic wastewater input in the gulf, whereas similar facilities are completely lacking in FYROM. On the other hand, several parts of the Axios River delta are designated as protected areas, in an effort to protect environmentally rich habitats. These efforts are often disputed by local stakeholders, which have conflicting interests in the use of the hinterland and the coastal environment. The need of an integrated catchment-coastal zone management plan appears as a fundamental priority in order to protect, improve and maintain the environment, taking into account the need for economic development of the area. The DPSIR conceptual framework appears to be a valuable tool, as it enables parallel assessment of socioeconomic and environmental issues. In combination with the application of numerical models, the DPSIR analysis may provide suggestions for sustainable and environmentally-friendly measures to policy makers.SI: Pirrone  相似文献   

10.
Environment, Development and Sustainability - The inclusion of sustainable development principles in project management is one of the main development scenarios for companies seeking to ensure...  相似文献   

11.
Land use change is the main driving force of global environmental change and is considered as very central to the ongoing debate on sustainable development. Even though large volume of literature materials is available of land use/land cover (LU/LC) change for many areas, very little is known of it in the floodplain of the Sokoto Rima River Basin of Nigeria despite the basin’s strategic importance. Thus, this study characterized the basin’s LU/LC and its change using computer-based digital classification of near-anniversary Landsat 5 TM imagery of November 23, 1998, and Landsat 8 OLI of December 2, 2013. The results of the digital classification were complimented with field-based observations on major observable characteristics of every LU/LC identified. Thirteen classes (forest area, dense grassland, grassy fallow, grazed open grassland, open cultivation, open grain fallow farmland, pepper cultivation, rice farmland, scrubland, sugarcane farmland, dry bare land, sand deposit and wetland/water) were characterized and the nature and extent of their changes assessed. 40 % of the basin’s uses is under cultivation, 22 % is under fallow, 27 % is either degraded or non-cultivable, while 11 % is forested. Change events include forest loss, increase in area cultivated, expansion of shrub/scrubland and pervasiveness of grazing. The changes were more pronounced in the upper than either the central and southern segments of the basin. In general LU/LC changes in the basin are reflection of increased human population pressure and effects of climate change. The LU/LC patterns and changes suggest underutilization and mismanagement of the floodplain which have impact on soil, hydrology and biodiversity with serious implication for livelihood and food security. The study recommends that interventions are needed to promote enhanced and sustainable management of land, water and vegetation resources in the basin, with particular emphasis on empowering the local land users to participate actively toward sustainable management of the floodplain.  相似文献   

12.
The eminent crisis threatening biological and resource diversity is a global adversity. Global resource diversities are constantly disappearing and deteriorating at quite an alarming proportion, provoking renewed thinking regarding the effectiveness of existing environmental management approaches and practices. For the past four decades, several epochs of environmental management policies and practices disregarded the cultural imperative for safeguarding efficient environmental management outcomes, particularly at the community level. Even in the rouse of this reality, issues of spirituality and how it binds local community people to their natural environment appear to be given only a window dressing attention through the recognition of sacred natural sites. Eight sacred groves and shrines in the Bongo District were investigated based on an endogenous development framework. The data were collected using focus group discussions with stakeholders at the local and district levels and individual interviews with key local natural resource managers from four selected communities. The study revealed that the way indigenous people construct the worldviews and interactions with nature using ancestors and other spirit mediums can safeguard the environment against long periods of human interference and destruction. It also demonstrates that in certain places traditional institutions are becoming malleable and open to the use of external knowledge and resources in order to sustain places of sacred significance. It concludes that cultural imperative and the issues of spirituality are critical for the sustainable management of environmental resources. The study recommends revisiting local practice and cultural values that promote good environmental management practices within the local communities.  相似文献   

13.
The paper demonstrates why it is necessary to take the restoration of marine coastal ecosystem health as a new goal for integrated catchment management, in coastal area of the Tolo Harbour. The present goal of integrated catchment management (ICM) in the Tolo Harbour is to meet with Water Quality Objectives. The performance of an ICM plan, Tolo Harbour Action Plan (THAP), is evaluated by using marine coastal ecosystem health indicators including stress indicators and responses indicators. Since the implementation of THAP in 1988, some significant reduction in pollution loading has been observed - reduction of 83 % of BOD load and 82 % of TN between 1988 and 1999. There has been an improvement in the health state of Tolo Harbour marine coastal ecosystem as evidenced in the trends of the physical, chemical and biological indicators, although some reverse fluctuations in some periods exist. However, this can only be considered as the first sign of the ecosystem health restoration, since ecosystem health co  相似文献   

14.
Environment, Development and Sustainability - The growth of secondary and tertiary sectors in the peri-urban villages results in development strain and causes demographic, socio-economic, and...  相似文献   

15.
The signature and ratification of the convention on biological diversity by the Lebanese government has boosted the declaration of nature reserves. Cedar forests formed the pilot ecosystems, using international funds, for the implementation of a conservation programme and development of management plans. Although different in their attributes, all recent nature reserves have the same basic management objectives and goals but they ignore the idea of taking into account the difference in specific site features and assets that could boost the success of any management plans. Twelve cedar forests flourish in the Mount Lebanon chain. These forests are either protected by the forestry law or are declared as nature reserves by the Ministry of Environment. The results reveal, through Participatory Rural Appraisals and Rapid Rural Appraisals, that religion, geographical location and land ownership play, to a certain extent, a role in adopting successful management practices of cedar forests. The RRAs and PRAs spell out the origins of woodcraft, old stories memorized by elderly people and ethnobotanical knowledge. The 4Rs tools method adopted highlighted the need for more collaboration and synergy of effort between various institutions. The social, ecological and economic aspects of the regions play a major role in defining the backbone of management plans for cedar forests in Lebanon. The present paper proposes guidelines for the establishment of a network of cedar nature reserves in Lebanon adopting collaborative management and assigning a separate role for each reserve; the details rely on the site’s natural features, as well as socio-economic and cultural characteristics. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue  相似文献   

16.
Transhumant pastoralism is one of the dominant livestock production systems in West Africa, and it is characterized by seasonal and cyclical movement of varying degrees between complementary ecological areas. The common pattern of transhumance is moving herds from areas with pasture and water scarcity such as the Sahelian zone to areas where the forage and water are found, often in the sub-humid zone. Whereas the transhumant herds from the Sahel are mainly Zebu breeds, endemic ruminant livestock (ERL) are the dominant breeds in sub-humid zone of West Africa because of their tolerance to tsetse-borne trypanosomosis disease. These livestock fulfill different functions in the livelihood of rural communities in the region. To identify potential areas of interventions for sustainable natural resource management to improve ERL productivity, a desk study that included spatial mapping was performed to review and document the existing knowledge on transhumance in West Africa. Additionally, group discussions were held to analyze the (actual or potential) effects of transhumant herds on natural resource management and ERL in the sub-humid zone. This study covered sub-humid zone in The Gambia, Guinea, Mali and Senegal. The key question we addressed in this study was as follows: What are the key trends and changes in transhumant pastoralism and how do these impact sustainable management of natural resources including endemic livestock? The results of the desk study and group discussions showed that there have been more southerly movements by transhumant pastoralists into the sub-humid zone over the past three decades and this has contributed to growing competition for grazing resources. The presence of transhumant herds in the sub-humid zone has a potential impact on management and conservation of ERL through crossbreeding with transhumant Zebu breeds from the Sahel but only study sites in Mali showed a high risk.  相似文献   

17.
In projects of community development and natural resource management, local residents collaborate with government and NGOs on decisions about forest management and participate in programs designed to improve livelihoods while sustaining natural resources. This paper uses case studies and survey data in Gansu province of northwest China to explore social, ecological, and economic outcomes of community-based co-management (CBCM). Findings show that CBCM appears to have significantly increased livelihoods for local community residents overall. Forest condition and attitudes about forest conservation were also improved. However, economic benefits were not enjoyed uniformly within the communities because, although CBCM projects are nominally available to all, certain subgroups within communities are less likely to participate. Greater education, being married, and access to information are all strongly correlated with participation and thus the economic benefits of CBCM projects. Women, although they frequently participate in household decisions, are infrequent participants in CBCM projects, perhaps because project design does not meet their needs. Future improvements to CBCM project design should include increased access to information, education, and equitable treatment of diverse stakeholders in the decision-making process. Such improvements would likely lead to improvements in livelihoods as well as more sustainable forest management and conservation.  相似文献   

18.
This article examines the changes in land-use/cover types in the Irangi Hills, central Tanzania during the last 45 years and how such changes have influenced environmental and agricultural sustainability in the area. The spatial and temporal changes of land-use/cover were analysed through aerial photographs interpretation. Local perceptions and experiences of changes were addressed through household interviews and field observations. Results from this study show that during the last 45 years open and wooded grasslands, and other tree-cover types covered about 40% of the land area, ranging from 29% in 1960 to 43–45% between 1977 and 1992. Also, during the same period both the total area and spatial distribution of cultivated fields varied greatly. The cultivated area increased from 31% in 1977 to 35% in 1992, mainly due to agricultural expansion into areas formerly used for grazing and in sandy watercourses that shrunk by 55% between 1977 and 1992. The spatial distribution of the different land-use/cover types is influenced by variations in the scale of soil erosion and soil-conservation initiatives implemented in the Irangi Hills since the early 1970s. However, with increasing pressure on the land, and the declining capacity of the soil conservation authority, sustaining agricultural production in the area remains a major challenge.  相似文献   

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Fertility status of soils of three wetland types in Akwa Ibom State, Nigeria, was investigated. The wetland types are Inland Valley (IV), Flood Plain (FP) and Mangrove (MG). The soils have silt-clay ratios above 0.15 and 0.25 indicating that they are of young parent materials with low degree of weathering and possible weatherable minerals for plant nutrition. The pH of the soils was near neutral (>6.4) when wet but extremely acid (>3.5) when dried indicating that the soils are potential acid sulphate soils. Organic matter content was high with mean values of 12.59, 6.03 and 3.20% for IV, FP and MG soils, respectively. Total N (nitrogen) was low except in IV soils where the value was above the 0.30% critical level. The C:N ratios were narrow with mean of 20.90, 12.17 and 12.12 for IV, FP and MG soils, respectively. The contents of basic cations [Calcium (Ca), Magnesium (Mg), Potasium (K) and Sodium (Na)] were low while acidic cations [Aluminium (Al) and Hydrogen (H)] were high. The Ca:Mg ratios were below the optimum range of 3:1 to 4:1 required for most crops. The Mg:K ratios were above 1.2, below which yields of crops like corn and soybean may be reduced. Effective cation exchange capacity (ECEC) was below the 20 cmol/kg. Percent base saturation was low (<38) indicating that the soils are potentially less fertile. Exchangeable Al and percent Al saturation were high, above 60% in IV and FP soils. Electrical conductivity was above the critical value of 2 dsm−1 while exchangeable sodium percentage was less than 15. Available Phosphorus (P) and low, <10 ppm and free Fe2O3/clay ratios were <0.15. Positive correlation existed between silt and ECEC, implying that silt contributed to nutrient status of the soils. Generally, fertility status of the soil is low and would require maintenance of adequate organic matter, application of lime and organic and inorganic fertilizers, drainage and irrigation if the land is to be used for intensive/sustainable crop production. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   

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