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1.
Despite decades of soil and water conservation (SWC) efforts in Tanzania, the adoption of the recommended SWC measures by farmers is minimal. In the past, SWC plans did not incorporate farmers' knowledge, and the economics of SWC was not given much attention at the planning stage. This research evaluated the applicability of two tools for participatory soil erosion mapping using farmers' indicators of soil erosion and financial analysis of SWC measures at the planning stage. The two tools were evaluated in Kwalei catchment in the West Usambara highlands, Tanzania. The participatory soil erosion‐mapping tool uses farmers' indicators of soil erosion to identify, classify and map soil erosion at the catchment level. The financial analysis tool involves farmers in a stepwise analysis of the costs and benefits of SWC measures before the implementation. The erosion‐mapping tool increased farmers' awareness on the severity of soil erosion problems, and they realised the need for SWC plans at both field and catchment scales. With the financial analysis tool farmers participated in the cost and benefits analysis and were able to select SWC options that were feasible under their socio‐economic situation. The two tools were able to demonstrate that farmers' participation in SWC planning increases the acceptance of SWC measures because they solve problems that are perceived by themselves. The financial analysis tool demonstrated how farmers could make selection of SWC measures that are feasible under their biophysical and economic condition if they are informed about the costs and benefits. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

2.
Despite several approaches that aimed at mobilising East African farmers to embrace soil and water conservation (SWC) activities, farmers hardly responded since they were seldom involved in the planning of SWC activities. Two tools that employ farmers' participation were developed and applied at Gikuuri catchment in Kenya. The first tool involved farmers to map soil erosion using their own indicators and determine the soil erosion status at catchment scale. This formed the basis upon which they undertook to plan for SWC measures at catchment scale. Farmers also predicted crop yield losses based on the soil erosion status. Farmers widely approved the soil erosion status map since their own indicators and perceptions were used. The second tool provided cash flow trends for a variety of SWC activities and farmer situations. Farmers can use land with a high, moderate or low erosion status and often have rather different socio‐economic settings. The net benefits over 5 yr for bench terraces, fanya juu terraces and grass strips were illustrated to assist farmers in making informed decisions on SWC adoption. The two tools increased awareness on the need for collective actions among farmers and showed fields that cause run‐on on downslope fields. The improved awareness of erosion problems and the related financial consequences increased farmers' willingness to share the investment costs for cut‐off drains. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

3.
Accelerated soil erosion is one of the major constraints to agricultural production in many parts of the Tanzanian highlands. Although several soil and water conservation technologies have been developed and promoted, the adoption of many recommended measures is minimal and soil erosion continues to be a problem. This research was conducted in order to determine the social and economic factors that influence adoption of soil and water conservation (SWC) measures in the West Usambara highlands, Tanzania. For this research a household survey, group discussions and transect walks were undertaken. A total of 104 households were interviewed and several fields were visited during the transect walks. Data was analysed with the use of cross‐tabulation, cluster analysis, factor analysis and chi‐squared methods. The results obtained indicate that involvement in off‐farm activities, insecure land tenure, location of fields and a lack of short‐term benefits from SWC are among the major factors that negatively influence adoption of SWC measures. Membership in farmer groups, level of education, contacts with extension agents and SWC programmes were found to be positively influencing the adoption of SWC measures. Recommendations to facilitate adoption of different SWC measures include: integration of social and economic factors into SWC plans; the creation of more awareness among farmers of soil‐erosion effects and long‐term benefits of SWC; the development of flexible SWC measures to cater for different farm patterns and a participatory approach to SWC at catchment level rather than at individual farmers' fields. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

4.
A lack of appreciation of Kenyan farmers' knowledge and their perceptions of soil erosion and soil conservation measures was the reason for low adoption of recommended technologies. This research was carried out to identify the criteria that farmers used to distinguish farm‐types and to use these types to evaluate different knowledge levels and perceptions of soil erosion and existing soil and water conservation (SWC) measures in the Central Highlands of Kenya. Community meetings and semi‐structured household surveys were carried out in a small catchment, with 120 households. Results partly support the idea of using farmer‐developed criteria to distinguish among land managers with reference to a farm‐type classification. Criteria distinguishing three classes of land managers (good, moderate and poor) were significant with regard to the following land husbandry practices: use of hybrid or recycled seed and use of organic and/or inorganic fertilizers. Farmers were aware of on‐going soil erosion and of several erosion control measures. Whereas a majority of farmers preferred grass‐strips as a SWC measures, they did not recognize agroforestry as a form of SWC measure. Farmers perceived that SWC measures could successfully increase crop yields and soil‐water retention, and increase land value. In general, farmers did not perceive that SWC measures successfully prevented erosion phenomena, given the evidence of on‐site erosion indicators. They attributed the continued erosion to high rainfall, steep slopes, lack of maintenance and poorly designed SWC measures. They did not consider poor soil‐cover, up‐down tillage and tall trees to be the causes of erosion. Farmers faced several constraints in adopting SWC measures: lack of labour, tools, capital and know‐how to construct the measures. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

5.
Choices in project approach affect the continuation of soil and water conservation (SWC) after project withdrawal, and thus the sustainability and cost effectiveness of the project. A SWC project was carried out in southern Mali between 1986 and 1998. Its features were the promotion of cheap and simple SWC measures, a participatory village extension approach with limited use of incentives, and the incorporation of the SWC programme in an existing Malian extension service. By 2000, farmers in half the 5000 villages in southern Mali had been trained in SWC. By 2002, erosion‐control measures had been installed in 94 per cent of the villages in southern Mali by 46 per cent of the farmers and in 15 per cent of the fields. Though external donor support has stopped, farmer adoption is steadily continuing and spreading to untargeted villages. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

6.
Intensification of land use can become a threat to agricultural sustainability if they lead to increased soil erosion. This study examines land‐use changes, soil and water conservation, soil erosion and soil productivity in the Highlands of Kenya. In addition, it examines farmers' perception of livelihood changes. Land‐use changes were determined from interpretations of aerial photographs taken in 1960 and 1996. Additional information on land use, soil and water conservation and livelihood changes were obtained from discussions and interviews with farmers, as well as from field verifications of the most recent aerial photographs. Soil samples were analysed and soil erosion assessed according to the PLUS classification scheme. The results indicate that substantial changes in land use, such as introduction of coffee and high‐yielding maize, and fragmentation of land holdings have taken place. Less land was conserved in 1996 as compared to 1960. Moreover, SWC practices have changed from fanya chini terraces and shifting cultivation to bench terraces and permanent cultivation. Rates of soil nutrients (organic C, N and K) and maize‐yield levels decreased significantly with increasing erosion. Farmers' perception of livelihood changes was differentiated according to farmers' off‐farm resource 60 per cent of the farmers depended on income from the land and thought livelihoods were better in the 1960s. It is concluded that more efforts to decrease soil erosion and investments in land and labour are necessary to sustain soil productivity and hence secure rural livelihoods. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

7.
A soil and water conservation (SWC) extension programme, promoting erosion control measures and soil fertility measures, has been going on in southern Mali since 1986. Five factors that influence farmer adoption of SWC measures were analysed: land pressure, cotton‐growing area, possession of ploughing equipment, possession of a donkey cart and farmer training in SWC. Interviews were carried out with 298 farmers and two to three fields per farmer were visited, in 30 representative villages and 30 villages with high SWC adoption. Correlation, regression and factor analysis led to the following conclusions:
  • (1) Farmers in the high land‐pressure area adopt more soil fertility measures.
  • (2) Farmers in the cotton‐growing area adopt less SWC measures.
  • (3) Farmers with more ploughing equipment adopt more SWC measures.
  • (4) Farmers with a donkey cart adopt more soil fertility measures.
  • (5) Trained farmers adopt more erosion control measures.
There is a strong correlation between the adoption of erosion control measures and soil fertility measures that could not be explained by these five factors only. This suggests that there are additional factors that trigger the adoption of SWC measures. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

8.
Data and information about farmers' perceptions of soil degradation were collected using household survey, focus group discussion and field observations. The results indicate that farmers in the Sidama zone of southern Ethiopia are able to identify soil erosion and fertility loss indicators, take a holistic view of soil degradation and have a broad knowledge of the reasons for soil degradation. They perceive soil degradation mainly by reduced yields, soil changing in appearance and becoming stoney or coarse. The most frequently mentioned soil erosion indicator was soil becoming coarse and stony, followed by rill formation, dissection of fields and gullies and topsoil removal. The most important perceived indicator of soil fertility loss was reduced crop yield, followed by poor crop performance and yellowing of the crop. Farmers also have knowledge of solutions; however, participation in soil conservation activities is minimal because of the immediate threat of food insecurity. Any programme designed to address soil degradation in the region will have to be cognisant of farmers' knowledge and holistic view of soil degradation, and be integrated with aid measures to guarantee food security. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

9.
Farmers in many parts of Africa use indigenous soil and water conserving (ISWC) practices as an integral part of their farming systems. Farmers have developed such methods which have maintained productivity and contributed to long‐term sustainability, while introduced measures have often been rejected or simply failed to achieve their technical objectives. This paper examines the strengths and weaknesses of some ISWC practices in Kenya, Uganda and Tanzania. An evaluation has been carried out based on farmers' evaluation criteria as well as criteria identified by researchers. Farmers' criteria are often based on the quality of their natural resources (farmers are more likely to conserve those soils that will give the highest return on their investment), the resource level of the household (particularly income levels and labour availability), cropping intensity as well as cultural traditions related to age, education and gender. Of great importance, however, is the need to maintain or increase soil productivity. Methods that conserve moisture, reduce soil erosion, maintain soil fertility and increase productivity, which are socially acceptable and economically viable, are those which farmers favour. ISWC practices often have these qualities but farmers have not always been able to adjust the techniques to rapid changes in farming systems and increasing intensity of land use. Soil productivity and economic modelling indicate that although yields declines are lower when traditional technologies are used, long‐term productivity remains a problem. There is an urgent need to work closely with farmers to improve and develop traditional SWC techniques. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

10.
Soil is the basis of production in agriculture activities. The combination of intensive farming activities, improper farming practices, rainfall regimes, and topography conditions that taken place in agricultural land lead to the soil erosion problem. Soil erosion is the major constraint to agriculture that affects the yield production and degraded environmental sustainability. Furthermore, soil erosion that occurs in the agricultural area has jeopardized the sustainability of agriculture activities. Asia is one of the major agricultural producers in the world. It is essential to know how to mitigate soil erosion in Asian agricultural land. This systematic review aims to analyze the existing literature on research that has been done on control practices that had been taken in Asia agricultural land towards soil erosion. This article is guided by the PRISMA Statement (Preferred Reporting Items for Systematic reviews and Meta-Analysis) review method. The authors systematically reviewed the literature to study the control practices that been taken and tested to control soil erosion on the agricultural land in Asia. Accordingly, this systematic review identified 39 related studies about the topic based on the Web of Science and Scopus databases. This article divided the control practices into three main themes, which are agronomic practices, agrostological practices, and mechanical practices. The three main themes then produced a total of 11 sub-themes. Further specific and sustained research is needed to tackle this severe environmental problem through a better method, such as this systematic review method. The systematic review helps farmers and policymakers to implement the most practical approach to control and reduce soil erosion.  相似文献   

11.
After gaining independence in 1975 the government of Cape Verde embarked on large scale nationwide employment schemes to carry out soil and water conservation, (SWC) work. Impressive numbers of erosion control schemes have been realized on a scale not seen in other Sahelian countries. the programmes have largely concentrated on mechanical protection and afforestation. Little is known about the impact of these massive SWC activities on agricultural production. Employment has been created by establishing workgangs (frentes de trabalho), which became an important source of income, in particular for the numerous landless peope. These frentes have become institutionalized, and at present their role is increasingly under criticism. Serious problems have arisen with regard to the participation of local land users in the management of natural resources. the consensus now is that local land users should be given greater responsibilities for resource management, supported, where necessary, by the state. However, The role of frentes can be cut back only gradually due to the lack of viable employment alternatives in other sectors of the economy.  相似文献   

12.
In semi-arid areas under rainfed agriculture water is the most limiting factor of crop production. To investigate the best way to perform fallow and its effect on soil water content (SWC) and root growth in a barley (Hordeum vulgare L.) crop after fallow, an experiment was conducted on two soils in La Segarra, a semi-arid area in the Ebro Valley (Spain). Fallow was a traditional system used in these areas to capture out-of-season rainfall to supplement that of the growing period, usually lasting 16 months, from July to October of the next year. Soil A was a loamy fine Fluventic Xerochrept (Haplic Calcisol, FAO) of 120 cm depth and Soil B was a loamy Lithic Xeric Torriorthent (Calcaric Regosol, FAO) of only 30 cm depth. The experiment was continued for four fallow-crop cycles in Soil A and for two in Soil B. In Soil A, three tillage systems were compared: subsoil tillage (ST), minimum tillage (MT) and no-tillage (NT). In Soil B, only MT and NT were compared. In the fields cropped to barley, SWC and root length density (LV) were measured at important developmental stages during the season, lasting from October to June. In the fallow fields SWC was also monitored. Here, evaporation (EV), water storage (WS) and water storage efficiency (WSE) were calculated using a simplified balance approach. The fallow period was split in two 8-month sub-periods: July–February (infiltration) and March–October evaporation (EV). In Soil A, values of WSE were in the range 10–18% in 1992–1993, 1993–1994 and 1994–1995 fallow, but fell to 3% in 1995–1996. Among tillage systems, NT showed significantly greater WSE in the July–February sub-period of 1992–1993 and 1993–1994 fallow, but significantly lower WSE in the March–October sub-period, due to greater EV under NT. Consequently, no differences in total WSE were found between tillage systems. In Soil B, WSE was low, about 3–7%, and there were no difference between tillage systems. During the crop period, the differences in SWC and LV between tillage systems were small. Regarding yields, the best tillage system depended on the year. NT is potentially the best system for executing fallow, but residues of the preceding crop must be left spread over the soil.  相似文献   

13.
Soil water content (SWC) has a vital role in a variety of hydrological processes such as infiltration, runoff and erosion. Mapping the spatial pattern of SWC is then essential for appropriate addressing of these processes. Geostatistics is often used to characterize the spatial variability of SWC. This information may be used for estimating SWC e.g., by ordinary kriging (OK) or modeling location-specific uncertainty (local uncertainty) of the estimates by indicator kriging (IK). Kriging-based algorithms however smooth out the details and are incapable of detecting multi-location uncertainty (spatial uncertainty) of SWC estimates. Sequential Gaussian simulation (sGs) can model the spatial uncertainty through generation of several equally probable stochastic realizations. In this study sGs is used to map SWC spatial distribution and to provide a quantitative measure of its spatial uncertainty in particular. The SWC measurements were performed on 157 soil samples taken from an 18 ha erosion experiment field in Lower Austria. The results show that the spatial pattern of SWC is well recognized using the sGs as the simulated models reproduce the sample statistics including histogram and semivariogram model reasonably well. The difference among realizations is used to provide a quantitative measure of spatial uncertainty of SWC estimates. Knowledge of spatial uncertainty is helpful to evaluate the delineation of vulnerable areas to erosion.  相似文献   

14.
Soil erosion due to smallholder agriculture in upland areas of the Philippines is widely regarded as the country's most serious environmental problem. There have been many upland development projects involving the promotion of soil conservation and agroforestry measures. Yet adoption of such practices has been minimal. A research project was commissioned to investigate the technical and socio-economic factors limiting adoption of recommended soil conservation technologies. The project involved case studies of seven locations where conservation farming had been intensively promoted and adopted by a significant number of farmers. The research methods involved a combination of reconnaissance or rapid rural appraisal methods followed by a questionnaire survey of a sample of farmers from each site. This paper summarizes the project's findings regarding the farm-level factors associated with the adoption of recommended soil conservation technologies in the case-study sites. Its focus is on the attributes of the farm-household influencing the adoption-decision process, and the consequences of adoption at the level of the farm-household system. It was found that conservation farming technologies, particularly hedgerows, were widely seen by farmers who were aware of them as useful and even necessary, but it had required resource-intensive project intervention to get the adoption process going, and adoption was often constrained by farmers' specific circumstances, rather than their personal attributes and perceptions. A wider range of more profitable and less demanding conservation technologies was needed, promoted more flexibly and with greater, on-going support for farmers in their efforts to experiment with improved farming systems. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

15.
Soil degradation in the highlands of Ethiopia is a serious problem that threatens the sustainability of agriculture. Although efforts have been made to develop and promote several soil conservation technologies, their adoption has not been widespread. This study, based on responses from a sample of 101 households which operate on 204 plots in Western Ethiopia, interviewed in 2003 cropping year, employed a Tobit model to identify the main factors influencing farmers' decision to adopt and intensify the use of improved and indigenous soil and water conservation (SWC) measures. The results suggest that area of cultivated land, land/labour ratio, age and education level of household head and distance of the plot from home and slope of the plot provided statistically adequate predictive power on the use and intensity of SWC measures. These results are discussed and their implications for conservation programs are presented in the conclusion. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

16.
This study analyzes effects of soil and water conservation (SWC) on soil quality and implications to climate change adaptation and mitigation in the Upper Blue Nile River Basin of Ethiopia by using the Anjeni watershed as a case study site. Disturbed and undisturbed soil samples were collected from two sub‐watersheds of Anjeni: the Minchet sub‐watershed (with SWC measures) and the Zikrie sub‐watershed (without SWC measures). Soil samples were taken from 30‐cm depth from five representative landscape positions and analyzed following the standard soil lab analysis procedures. The results show that soils from the conserved sub‐watershed had improved quality indicators compared with those from the non‐conserved site. Significant improvement due to SWC measures was observed in the soil hydrological [total moisture content (+5·43%), field capacity (+5·35%), and available water capacity (+4·18%)] and chemical [cation exchange capacity (+4·40 cmol(+) kg−1), Mg2+ (+1·90 cmol(+) kg−1), Na+ (+0·10 cmol(+) kg−1)] properties. SWC interventions significantly reduced soil erosion by 57–81% and surface runoff by 19–50% in the conserved sub‐watershed. Reduction in soil erosion can maintain the soil organic carbon stock, reduce the land degradation risks, and enhance the C sequestration potential of soils. Therefore, adoption of SWC measures can increase farmers' ability to offset emissions and adapt to climate change. However, SWC measures that are both protective and sufficiently productive have not yet been implemented in the conserved sub‐watershed. Therefore, it is important that SWC structures be supplemented with other biological and agronomic measures in conjunction with soil fertility amendments appropriate to site‐specific conditions. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

17.
关于我国水土保持科学的内涵与研究领域问题   总被引：11，自引：4，他引：11       下载免费PDF全文
 根据《中国大百科全书·农业》及《中国大百科全书·水利》中水土保持条目的定义说明中国水土保持科学的内涵及范畴。指出:水土保持的内涵是山丘区及风沙区水土资源的保护、改良与合理利用;水土保持科学的研究范畴包括水土流失规律、水土保持规划、水土流失综合治理技术措施、水土保持管理、水土保持效益评价等。还提出了近期需要特别重视的研究课题。  相似文献   

18.
Abstract

Soil erosion by water is currently one of the most notable types of land degradation in Samanalawewa Watershed in Sri Lanka, creating copious environmental and socioeconomic impacts. Thus, with the aim of detecting and mapping the rates of human-induced soil erosion in the watershed, remote sensing and geographic information system based modelling and field experiments were carried out. The results of the assessment disclosed that the present rate of human-induced soil erosion varies from 0 to 289 t ha?1 yr?1 with the majority of the area exceeding the natural rate of soil erosion by 14 to 33 times at present. However, the average rate of human-induced soil erosion has declined dramatically from 19.8 to 4.3 t ha?1 yr?1 from 1986 to 2008. In order to analyse the significant determinants of farm-level adoption of soil and water conservation measures, binary logistic regression procedure was applied using the data collected through a household survey (n = 201). The most significant (p<0.01) variables of the study were the farmers’ perceptions of soil erosion problems, gender of the household head, training on soil and water conservation, and ascertained advice from agricultural extension officers while the variables regarding past awareness about soil conservation technologies and off-farm income were significant at p<0.05. Furthermore, the study revealed that the majority (60.2%) of the farmers in the study area had been adopting different types of soil and water conservation measures for a prolonged period of time. Therefore, owing to the current decreasing rate of soil erosion, the soil and water conservation costs and the ratios of human-induced soil erosion vs natural soil erosion had declined significantly while the productivity of their lands had gone up.  相似文献   

19.
Land shortages are forcing more smallholder farmers to cultivate tropical steeplands. Resulting accelerated soil erosion is being countered by the promotion of soil conservation (SC) technologies, such as cross‐slope barriers, which aim to reduce soil loss and preserve land productivity. However, farmer adoption rates tend to be low. This is often attributed to the farmers' conservatism or lack of education. Research in Honduras's steeplands demonstrates that farmers value SC, provided that it promotes agricultural production. Field research from 1995–98, involving farmed test plots on slopes greater than 35 per cent (19 degrees), demonstrates that at least one typical SC technology—live barriers of Vetiveria zizanioides (vetiver grass)—has little or no impact on maize yield. This means that farmers see little benefit from their investment in the SC method. They find that erratic rainfall, pests and diseases and a lack of economic resources are far greater threats to their livelihoods than soil erosion. Consequently, SC has a low priority. Keeping soil in place avoids major off‐farm disbenefits. However, the SC technique tested here made no discernible difference to slope foot sediment yields during the life of this study. In sum, a new approach is needed. Promoting ‘Better Land Husbandry’ strategies, which seek to combine farmers' concerns about productivity with conservationists' concerns about reducing soil erosion—often via cover‐management—seem to be the best way forward. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

20.
Human land use of the Tigray landscape (north Ethiopia) can be traced back for at least 3000 years and is recognizably very complex, but in the past half-century there have been multiple narratives on environmental change in the Northern Ethiopian Highlands in which statements such as “the forest and soil resources in Tigray are dwindling at unprecedented rates” are common. In an attempt to provide an objective assessment, we made a semi-quantitative analysis of observed changes in the environment of the central Tigray plateau, between 1975 and 2006, and its impact on soil erosion. The first part of this period saw strong degradation, caused by a combination of drought, impoverishment, poor land husbandry and war; but over the whole period intense rehabilitation activities have been high on the agenda. To study these changes, two sets of 51 landscape photographs have been used. The older photo-set was taken in 1975 by R.N. Munro during the Tigrai Rural Development Study; locations were revisited in 2006 by J. Nyssen and colleagues, when a new set of photographs was made at the same locations and with the same aspect. Based on longstanding experience in soil erosion and landscape analysis worldwide and in Ethiopia, the time-lapsed photographs were rated for visible erosion, land cover and protective measures. We present a quantitative evaluation of the change of soil loss by sheet and rill erosion, involving the Universal Soil Loss Equation (USLE) and particularly the changes in the C (cover) and the P (management) factors. This allowed assessing soil loss in 2006 as a percentage of the 1975 situation. Both the landscape and land unit analysis show that the situation for natural resources has improved (and locally strongly improved) since 1974. The rehabilitation is due both to improved vegetation cover and to physical conservation structures. The USLE application indicates that in terms of a whole landscape the current average soil loss would be at around 68% of its 1975 rate. Exceptionally, degradation is still ongoing around Desa'a forest and some other remnant forests, and conservation should be strongly implemented too in these forests. On average, gullies have expanded slightly since 1975, but these incisions appear to have originated in the drought years of the 1980s. This photo-monitoring analysis invalidates hypotheses on (a) irreversibility of land degradation in Tigray; and (b) futility of Soil and Water Conservation (SWC) programmes. The study demonstrates that (a) land management has become an inherent part of the farming system in Tigray, and (b) that the authorities and NGOs are on the right track when promoting SWC.  相似文献   

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