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13: Interacting with the environment: Adaptation and regeneration on degraded land in upper Manya Krobo
14: Land use and cover change in the southern forest-savanna transition zone in Ghana: A sequence model
15: Women, environmental change and economic crisis in Ghana

13: Interacting with the environment: Adaptation and regeneration on degraded land in upper Manya Krobo

Upper Manya Krobo
Research methodology
Land degradation and its consequences
Adaptation, regeneration and innovation
Implications for research
Acknowledgement
References

Kojo Sebastian Amanor

The future of Ghana will depend on the ability of its people to maximise the utilisation of all available resources within the local ecosystem. That includes the local physical and biological resources, the local human ingenuity, mental resources and energy and the vast local cultural resources (Anquandah 1985).

At present, environmental policies in the agricultural sector in Ghana are largely concerned with disseminating internationally generated technology and commodity packages focused on agroforestry. There has been little priority given to appraising the perceptions and needs of the farming peoples, their experiences with the environment and their traditions of environmental management. Dominant policy frameworks tend to argue that unless there is improvement in the system of farming there will be a devastating effect on the environment, that methods of slashing and burning seriously affect the environment and that tree planting programmer should be initiated. These tree planting programmes have focused on fast growing exotic species.

There is a tendency to dismiss farmers as illiterate and their knowledge as inconsequential. Dominant policy frameworks promote the need to "educate" them and get them to take up "commodity packages" of international agricultural research. International development structures promote this top-down approach, since they tie up aid with the dissemination of international commodity technology, and put pressure on government services to achieve results in terms of number of trees planted and number of farmers taking up new "green" technology. International development aid also funds applied research in developing countries based on extending the technology of international centres and agribusiness, but shows little interest in developing basic research into the environment and its problems. This breeds dependency and shallow research systems in which policy and research linkages with rural communities and knowledge of the conditions of life among the people are weak. This often results in contradictions, such as the fact that international research is willing to spend large sums on projects which deal with vague notions of biodiversity, yet is reluctant to fund the development of a list of plants on Ghana, which any serious project on biodiversity would require as a base.

Agricultural technology development is highly monopolistic and largely controlled by a few large multinationals which have established control over inputs and food markets. This has created serious problems in the genetic base of modern agriculture, which has become very narrow and dependent upon the products of multinational corporations. Many land races or folk varieties of plants have disappeared as a result of this monopolistic control (Kloppenburg 1988; Vellvé 1992).

Agricultural services often hide their weak research base by blaming farmers for problems or failure. Botchway (1993: 33) comments on research at the Weija Irrigation Project:

Without an institutional framework for research, problem identification and analysis, the Extension Unit took a defensive stance in its interactions with the farmers and was not receptive to ideas and information from them. Local knowledge was suppressed and farmers' preferences and evaluations were disregarded, helping to choke out the much-needed return flow of information.

In Ghana, the modern farm sector has a poor record in withstanding the vagaries of weather and also protecting the environment. Many of the state farms have closed down and those remaining have experienced crisis in yields resulting from unreliable rainfall. At Ejura State Farms, only 264 of 800 ha planted to maize were harvested in 1994 (Daily Graphic, 7 Sept. 1994). The sites of Ejura, Wenchi and Brenam state farms are hardly testaments to environmental management: the total denudation of trees on their land is a characteristic which makes them stand out from the surrounding mosaic of small farms.

While the agricultural sector tends to dismiss the knowledge of peasant farmers, it has been given its due in other branches of knowledge. The botanists Irvine (1961), Ayensu (1978) and Abbiw (1990) recognise both the breadth of folk knowledge of the environment and its uses, and the efficacy of folk herbal medical knowledge, which they documented. The Ghana Herbal Pharmacopoeia and the Centre for Research into Plant Medicine at Mampong Akwapim are products of the extension of folk knowledge. The archaeologist Anquandah (1985) has been impressed by the range of adaptations and management of the environment exhibited by the peoples of Ghana, revealed in archaeological sites from earlier centuries and surviving folk knowledge, and sees this accumulated technical and cultural knowledge as forming an important base for a renaissance to rescue Ghana from stagnation. The knowledge of local agricultural and agroforestry extension agents of the diversity of local environments and plant life pales in comparison, unless they are also heirs to the folk traditions of rural communities in which they were nurtured.

While technologies available for monitoring environmental change are now highly developed, it is also important to understand the social and political dimensions of environmental change. Land degradation is often the result of a complex interaction of factors which emerge through time. The existence of a particular quantity or quality of degradation within a locality at a given moment in time tells us nothing about the relationship of the people with the environment. The patterns of land degradation may be the result of past practices. As a result of negative experiences of land degradation, people may be changing their forms of resource exploitation to attempt to achieve a more balanced relationship with the environment. These changing modes of ecological adaptation may show up in the future as minor or major enhancements of the environments, or they may not show up as a result of failure to ameliorate the environment, resulting from technical, social or political problems. Nevertheless, these failed efforts do not negate the facts of conscious planned activity to ameliorate the environment.

Within the forest area of Ghana, many of the problems of environmental degradation do not result solely from the present actions of bush fallow cultivators on the land, but from the impact of the history of cocoa cultivation, the problems of regenerating cocoa once the original monoculture has died out, and the tenurial systems which emerged in the cocoa era (Amanor 1994a, 1994b). Cocoa is a frontier crop which has been planted extensively in the forest areas of Ghana. Since plantations can be established rapidly and with ease, large areas of the forest have been rapidly felled and converted to a cocoa monoculture. As cocoa is a moisture-loving crop which thrives in mature forest soils, once the original cocoa plantation dies out, it is difficult to re-establish in areas which were converted from forest into a cocoa monoculture. In recent years, new hybrid crops have been developed which can thrive outside forest conditions. However, unlike the early varieties of cocoa planted, these are less tolerant of shade, less resistant to disease and more susceptible of catching diseases from other species of trees. More forest trees have to be cut on the farm than with the old varieties of cocoa. This has reached crisis proportions recently where new diseases have broken out and farmers have been advised to remove all shade trees. As a result of disease, declining world market prices for cocoa, and the increasing necessity of expenditure of increasing sums of inputs, many farmers have been converting from cocoa to food crops for the urban markets since the 1940s. This has involved movement from monocultural orchard crop cultivation to a system of bush fallowing. The environmental problems which are emerging in this system are not the product of bush fallow cultivation, but a crisis generated in the cocoa sector.

Cocoa farming also led to rapid land commoditization and speculation at the end of the nineteenth, early twentieth century, with many local states alienating land to outside farmers and sharecropping labour. As a result, there is much land hunger, and in many areas 50 per cent of farmers are dependent upon hiring or sharecropping land on an annual basis (Amanor 1994a; Gyasi 1991). This creates major problems for sustained environmental management.

Upper Manya Krobo

The Manya Krobo area lies in the Eastern region of Ghana, in the south-east forest ecotone adjacent to the Afram branch of Lake Volta. Krobo farmers moved into Upper Manya Krobo between 1900 and 1920, purchasing land outright from the Begoro stool of Akyem Abuakwa. Land was specifically acquired for cocoa production. In the nineteenth century, the Krobo were the major cultivators of oilpalms, providing about 60 per cent of palm oil for the export trade (Wolfson 1953). With the growth of plantation production of palm oil in South-East Asia, the Krobo could no longer compete on the world market and converted to cocoa. Rather than transferring existing land from oil-palms to cocoa, they invested in the purchase of new forest land. These forests consist of dry outer zone semideciduous forests in the eastern settlements and wet semi-deciduous forests in the western settlements.

By the 1930s, cocoa in the eastern settlements began to suffer from stress: the outer forests were too dry for cocoa cultivation. This resulted in the swollen shoot epidemic of the 1940s, which led to the forced cutting out of cocoa and sounded the death-knell for cocoa in the area. The agrarian economy was transformed into a major maize growing area. The main crops grown were maize, oil-palms, cocoyam, yams, plantain, okra, garden egg, pepper and cassava. Cassava only became a major crop in the 1960s.

The Krobo farmers integrated their crops into a bush fallowing system, based on medium fallows of 3-6 years. This bush fallowing system is relatively modern, replacing a system of frontier monocultural export crop production. Until the 1970s, Upper Manya Krobo was the major food producing centre in Ghana. Since the 1970s, it has declined, and the northern transition zone of Brong Ahafo has emerged as the major food producing area.

During the 1960s, the construction of Volta Dam created much stress in Manya Krobo. Over 20 per cent of the land was inundated. This has created increased population pressure on the remaining land. Farmers also claim that the creation of the lakes has transformed rainfall patterns, resulting in poor and unreliable rain.

There has been a marked transformation of the environment since the 1960s in the areas around Lake Volta. Former dry forests which were once described as prime agricultural settlements now resemble scrub land and grassland, on which farmers struggle to eke out a livelihood. The settlements to the west, however, are in better condition. They still have the appearance of a forest environment, with a sparse upper storey of forest trees such as Milicia excelsa (odum), Triplochiton scleroxylon (otra: wawa), Terminalia superba (afram), T. ivorensis (amle: emire), Ceiba pentandra (Ieno), and Cola gigantea var. glab rescens (ovuga) dotted around the landscape, but an understorey dominated by Chromolaena odorata (acheampong).

Research methodology

Given these pronounced differences in the surface appearance of the forest, a survey was carried out along a west-east transect of 20 km from the edges of the wet semi-deciduous forest to the edge of Lake Volta. This survey investigated farmer interactions with the environment, charting crops, fallow systems, farming styles, and the various resources used by farmers from the fallow for chewing sticks, medicines, fencing poles, building materials, pestles, mortars, fodder etc. One hundred soil samples were also taken on plots without a history of inorganic fertiliser usage (Amanor 1994a).

The survey extended through the adjacent settlements of Odometa, Awoweso and Akrusu Saisi. The characteristic settlement pattern of the Krobo area comprises a valley and slopes which are divided into numerous farm strips running up the slopes, ensuring an equitable distribution of soil catenas and access to streams and wells. The width of the farm strips indicates the various sizes of the lands which farmers purchased. The Krobo live on their farm strips rather than in nucleated settlements (Benneh 1970; Field 1943). The settlements are known as huza Their houses are usually situated near the major path which runs through the settlements. Such a living arrangement makes the area ideally suited to a transect survey. Along this transect, changes in the natural environment were used as a criterion for sampling localities and administering a questionnaire which enabled interactions with the environment to be compared. Figure 13.1 shows the localities sampled on this transect and charts the distinct changes in the natural environment in different localities.

Land degradation and its consequences

Within all the settlements surveyed farmers complained about the repercussions of increased land degradation. This included increased weeding, resulting from the invasion of savanna grasses (Panicum maximum and Digitaria ciliaris) and pantropical weeds (particularly Chromolaena odorata); declining yields; failure of particular crops, such as yams and plantain as a result of changing environmental conditions and unreliable rainfall. Farmers tended to blame crop failures on unreliable rather than on declining soil conditions, insisting that if it rained, they could achieve satisfactory yields. Farmers also tended to match crops to soil, and argue that some crops will grow on most soils (thus, crop failure is the result of rainfall failure rather than declining soil fertility). When yields become marginal farmers may introduce long fallows and leave the land to rest for some time. Soil analysis revealed that most soils were in the range of 50 per cent of their optimum pre-cultivation level (Amanor 1994a).

Figure 13.1 Settlements Surveyed along the Transect

While most farmers complained of declining yields, this was more serious in the more degraded settlements of Awoweso and Akrusu Saisi. Many people were unable to feed themselves from their farms and were dependent upon purchasing staples from the market. However, there was no correlation with the degree of degradation and yields. As the degree of degradation increased and the vegetation transformed into Panicum maximum grassland, yields improved. This was because the farmers had worked out new adaptations to the environment. Paradoxically, the areas which suffered from the most serious agricultural crisis were those in which in earlier decades farmers had introduced fast growing exotic species for fuelwood and pole wood. Cassia siamea, Leucaena leucocephala (glauca) and Azadirachta indica (neem) were three tree species which farmers had introduced during the colonial era and which have spread rapidly to become major weeds, suppressing the regeneration of the forest seed and root mat. Farmers dislike these trees and find areas where they are dominant problematic to farm. They are difficult to weed and clear, and compete with crops. The planting of fast growing trees may appear to solve problems of declining forest biomass; however, in the long term, this may create unforeseen circumstances, promoting the spread of poor quality biomass which does little to ameliorate increasing desiccation and savannization, but exacerbates these processes by successfully competing against the regeneration of forest species and crowding them out of existence. These species may become "ecological pollutants" (Tuffuor 1992).

Adaptation, regeneration and innovation

In the more degraded settlements, farmers have had to struggle against major changes in the agroecosystem which have made their old styles of farming ineffective. A profound crisis over the last 20 years has forced farmers to reevaluate their farming methods and to engage in innovation. The hinterland around Lake Volta has become an experimenting ground.

During the 1970s, bushfires became common, spreading from the plains around Lake Volta. They became annual dry-season events. Trees and shrubs were burned and killed, and in their place grew grass, colonising areas of burnt forest. The Krobo farmers disliked the grass, having developed traditions of farming based on the cutlass and minimal tillage. Unused to tilling land with a hoe, the clearing and weeding of grass was tedious for them. Since the grass burned every year, the soils failed to build up organic matter and soil minerals. Farming on grass meant reduced yields for greater back-breaking labour. Originally the farmers ignored the grassland and cultivated the remaining forest land. As the forested areas shrank and became scarce islands surrounded by vast expanses of grassland, some farmers abandoned their lands and migrated to the new forest frontier areas in search of land. Those who stayed behind were forced to confront the grassland, by either adapting to it or fighting to reinstate the forest.

Adaptation

In the areas where grassland is dominant, the conventional bush fallowing techniques of the Krobo are not performing well. Fallowing does not result in efficient recycling of soil nutrients since the annual burn prevents the development of biomass and destroys the organic layer of the soil. Minimal tillage methods of weeding lead to rapid regeneration of soil. Without traditions of hoe cultivation, clearing takes a long time: on the average about 50 days for clearing half a hectare of grassland, as compared with 14 days for forest fallow.

Table 13.1 Soil Nutrient Recycling of Topsoils in Selected Localities

In response to these problems, many farmers are moving from multicropping to crop rotation systems, extending cultivation and incorporating cowpeas into the cropping cycle. In place of a single planting based on maize and cassava, planting is extended over three major and three minor seasons, in which, for example, maize may be followed by cowpea and then cassava, or maize-cassava may be followed by cowpea, maize, cowpea and then cassava. Several variations exist, which indicates that the farmers are experimenting with establishing optimal rotational cycles. Since fire is kept away from the cultivated plots and the legumes improve the soil status, these adaptations enable the build up of soil nutrients. Soil samples taken at Awoweso Sisi revealed an improvement in nutrient cycling of old farms, in which crop rotations were practiced, over new farms cleared from grass fallows (see table 13.1). Extended cultivation is also important in lessening the load of the large labour inputs involved in clearing the land every year.

These innovations have been successful to the extent that pure grassland is now being hired for a premium price and valued far above neem dominated scrub land, which still remains a problem for farmers to cultivate. Cowpeas command a good market price. Now their cultivation has spread into the more forested areas as a minor seasonal which is increasingly replacing maize. In these areas it is not cultivated in a crop rotational system.

While many farmers have adapted to the environmental changes by introducing the hoe, this results in a form of tillage which encourages the stabiliza tion of savanna conditions by disrupting the remains of the forest root and seed mat. Other farmers have responded to the changes by extending and adapting minimal tillage techniques to grassland. The farmers practicing this system wait until the first burn of the dry season has swept through the grassland. The grass is charred rather than severely burnt. The charred grass is uprooted with a cutlass and then laid across the ground as a mulch. This effectively prevents the later and more serious fires burning the land; it protects the soil from the sun and from leaching and suppresses the growth of weeds. The system involves a lot of back-breaking labour in clearing, which many people cannot perform. However, it results in minimal weeding. Those practising this system were the only farmers in the grassland areas of Awoweso whose yields of cassava had not deteriorated over the years but had actually improved.

Problems of erratic rainfall have also involved farmers in experimenting with cultivation near water sources. This is most evolved on the Volta lakeshore, where farmers have devised elaborate systems of flood retreat cultivation for the cultivation of sweet potatoes, tomatoes and cassava. This is carried out with exact timing in which the maturity of the crop (under a constant supply of water) is matched to the rise and fall of the lake. The lakeshore is the main focus of cultivation in its adjacent settlements, and consequently lakeshore land commands a premium price.

Other adaptations along the lakeshore involve a change from farming to fishing, and on grassland to small livestock and cattle.

Regeneration

Other farmers have responded to the ecological crisis by trying to preserve the vestiges of the forest ecosystem and using a minimal tillage mode of cultivation. In this they aim to harness the synergic interactions of the remaining forest species to confront the invading hoards of grass. During the survey, farmers were asked to estimate the numbers of various species of forest trees on their land. As we moved from Odometa to the Cassia siamea scrub land areas of Awoweso Kpeti, the number of trees dropped dramatically, although occasionally one or two forest species which were no longer existent at Odometa were mentioned. But when we reached open grassland, to our incredulity, farmers began to count pioneer species in the hundreds. We were extremely perplexed. When we asked them why so many trees had been cut, they were adamant that they did not cut trees but preserved them. Their fathers had cut trees in the old days but they did not now since trees were scarce. With visits to farms, we began to realise that the farmers were counting saplings a few inches high as trees and were intent on preserving them. Throughout this open grassland we began to observe numerous small pioneer forest trees. We had hit an area with a high tree consciousness. However, farmers did not plant trees, since they did not know which species to plant and how to plant them. They were sure if they planted them they would not do well. Many of these trees had grown from stolons, shoots and coppice. In the dry semi-deciduous forest, seed reproduction is often difficult and vegetative reproduction becomes important (Ewell 1980; Janzen 1975; Nyerges 1989). Common species which were being preserved include Newbouldia laevis (nyabatso), Baphia pubescens (tutso), Dialium guineense (mielesto), Trichilia monadelpha (gbagblabata), Albizia adianthifolia (papa), A. zygia (papaku), Ficus exasperata (slabatso), Holarrhena floribunda (osese), Ceiba pentandra (leno) and Nesogordonia papaverifera (bano). Several of these trees are leguminous, including Baphia, Albizia and Dialium. These trees can easily be integrated with crops since they do not develop large crowns. This focus on pioneer species is rational, since they are the species which start the process of forest regeneration. In terms of regeneration this makes more sense than planting monocultures of fast growing exotic trees, which can further disrupt the local ecology.

Apart from this preservation of pioneer species, some farmers were beginning to develop systematic agroforestry systems which incorporated these trees into specific agroecosystems planning with an integrated cropping component. In the course of research, two specific regenerative agroforestry systems were found.

The Nyabatso Agroforestry System

This agroforestry system focuses on Newbouldia laevis, a tree which can grow to about 20 m but which is characterized by a very slender crown. The tree is known as a medicinal plant and has been regarded in the past as the ideal tree under which to grow yams. It does not have to be burned because of its slender crown, and it is reputed to enhance the soil and result in large, quality yam tubers. Root suckers, stem shoots and seedlings are deliberately preserved. The tree can reproduce rapidly in fairly even distributions of between 3 and 6 m apart. Once the trees have established themselves on a plot, reaching a height of about 2 m, the undergrowth can be cleared for cultivation. The land is not burned since this may damage the trees. Crops are cultivated between the trees. Examples were found of maize, cowpea, oil-palms and cassava integrated as the cropping component. One woman farmer commented that she had decided to grow maize among nyabatso to see what would happen, indicating the experimental nature of the project. A second farmer stated that he had decided to preserve nyabatso throughout his land because he was experiencing a shortage of trees for firewood and yam cultivation. He intended to start cultivation with cowpea. Another farmer had preserved large densities of nyabatso about 3 m apart. He had introduced pollarding techniques to enable cultivation to take place. The cut branches were laid on the ground to provide mulch. Soil samples did not reveal any significant improvement in soils, although the two samples taken were insufficient to prove anything (see table 13.1). Nevertheless, the nyabatso agroforestry system looks impressive and reveals considerable experimental ability and knowledge of the agroecosystem.

Managed Pioneer Fallow

In this system farmers extended cropping on grassland for over three years as a deliberate strategy to influence vegetational succession. Long duration crops, such as pepper and cassava, are cropped. All regenerating trees on the land are preserved and a focused weeding regime is introduced in which grass is rigorously weeded out. By the third year, a plethora of small trees and shrubs begin to cover the land, typically consisting of Albizia spp., Baphia spp., Newbouldia laevis, Dialium guineense, Holarrhena floribunda and pawpaw. At this stage, the trees and shrubs overwhelm the land and few crops remain. The farmer abandons the plot, knowing that the forest elements have now got a head start and are likely to survive.

One farmer practicing this technique stated that his main objective in introducing it was to counter the effect of bushfires. He was developing a methodical strategy to gradually extend the managed fallow over adjacent lands, qualitatively transforming the grassland and creating a fire-break. A soil sample taken of this plot three months after it had been abandoned revealed an improvement in organic matter compared with grassland fallow. Another example of this system on land which had been last cultivated five years before was distinguished by superior secondary forest regeneration marked by the presence of many species of Antiaris toxicaria, Albizia spp., Trichilia monadelpha and Holarrhena floribunda. Soil analysis revealed a higher organic matter content and improved nutrient cycling over conventional fallows.

Implications for research

Since these agroforestry systems and adaptation of the cropping system were discovered by accident, there may be other systems also coming into being. While it is not possible to comment on the long-term efficacy or suitability for extension of these agroforestry systems, they nevertheless attest to the environmental knowledge of the people, their knowledge of environmental processes and their abilities to harness ecological processes methodically. These innovations seem to be concentrated in the most badly degraded areas, among farmers who are most likely to be dismissed by the agricultural and environmental sciences as "robbers of the soil," "aimless shifting cultivators" and "backward farmers." These farmers are carrying out this experimentation under conditions of increasing poverty and marginalization.

These traditions of experimentation among farmers can make a valid contribution to scientific knowledge. Their strength lies in an ability to interact with the environment and understand responses of the environment to human interventions. In contrast, the agricultural sciences have a weak knowledge of human-environmental interactions and agricultural ecology, since the basic focus of agricultural development has been on domination over nature, achieved through the use of chemicals and other inputs which have often been a serious source of environmental destruction. Agricultural research seeks to create artificial systems or commodity packages of inputs which sit above and replace the local environment rather than interact with it. This approach is being reproduced with the latest "green technologies," such as alley cropping, in which exotic fast growing trees are groomed to replace the natural flora. This system does not integrate itself with the synergic processes in local environments. As a consequence, alley cropping often involves high labour costs in tending these fast growing trees, which can easily overrun the farm. While Leucaena leucocephala is being presented as a new crop, all its positive features in raising soil fertility were noted by Irvine (1961) in the early 1960s. This, however, did not prevent him classifying Leucaena as a noxious weed. Some agroforestry researchers differentiate the current variety of Leucaena leucocephala from the variety introduced 200 years ago (Leucaena leucocephala glauca). Both nevertheless essentially share the same characteristics. Problems in controlling Leucaena have resulted in very low adoption by farmers. In the Eastern region, the two alley cropping species recommended, Leucaena leucocephala and Cassia siamea, occur as major weeds. Recently Cassia siamea has been dropped from the recommended species in the Eastern region since some problems have been noted in its interaction with crops. Had farmers adopted Cassia siamea on a large scale, what would be the consequences now?

A comprehensive adoption of alley cropping is likely to exacerbate environmental problems. It would result in the replacement of the diversity of the fallow by a tree monoculture which would suppress the fallow root and seed mat. The monoculture would eventually be highly susceptible to disease and pest attack, and spread through all surrounding lands as a weed.

In the light of these findings, a viable approach to environmental conservation would be to develop a research and technical services infrastructure which seeks to strengthen farmers' own experimenting traditions, enable them to place their research demands and needs on agricultural services, and inform them of development elsewhere which can prevent them from reinventing the wheel. In recent years, much has been written about farmer participation in international agricultural research (Amanor 1990; Biggs 1989; Chambers et al. 1989; Farrington and Martin 1988; Haverkort et al. 1991). Nevertheless, the fundamental structures of international agricultural research are not sympathetic to strengthening autonomous indigenous research. International agricultural research essentially regards farmers as consumers of technology (Röling 1990) produced by the holy alliance of international research centres and agribusiness. The role of international agricultural research is to "produce better commodity packages" and other commodities through which a cultural and economic hegemony is established over small farmers. National research is funded as a cog in this system to facilitate the domination of international agricultural research through "applied research" and, by implication, this denies the development of a flowering of local culture and craft, and science in the service of popular culture.

Acknowledgement

The research on which this article is based was supported by the United Nations Research Institute for Social. The views expressed are those of the author.

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