3.1. Indigenous Knowledge Levels and Sources
Perception is the way of processing raw data that a person receives through his/her daily and long-term interaction with immediate environment into meaningful pattern. Indigenous perception depends not only on individual personality but also on community, environment, and interaction among these components [
29]. Before taking any further analysis of indigenous knowledge and farmer perceptions of climate and ecological changes in the Bamenda Highlands of Cameroon, it was necessary to assess the peoples’ knowledge levels about climate change (
Figure 2).
One-third (32.2%) of farmers have very high knowledge of climate change, 54.8% have high knowledge, 4.5% have very low, 5.5% have low, and only 3% have no knowledge. Sources of indigenous weather activities on the Bui Plateau are through plant behavior (49.4%), personal intuitive perception (18.9%), animal behavior (12.2%), consultation of traditional weather seers (4.7%), stream behavior (6%), and consultation of community elders (3.7%) (
Table 3).
A small proportion of inhabitants of the population of the Bui Plateau uses conventional sources such as television, (0.8%), meteorological services (1.7%), radio (1.5%), and those who do not have any weather information (0.5%). The dominance of indigenous sources of weather activities is because most farming communities do not have access to electricity, which deprives them of gadgets like televisions and other electronic devices. Typical farmers in frontier basins like Lassin, Mbaw Nso, Nkuv, Gwarkang, Mbokam, Njanawa use mainly simple phones (for those who can afford) that can be charged with a small solar panel. This partly accounts why such farmers resort more to indigenous sources of weather activities than scientific weather information. Furthermore, indigenous farmers reported at about 47% that the language of conventional weather forecasting is too complicated and hard for them to comprehend. They also asserted that the situation is made worse by the absence of local weather scientists (37%) to teach them weather changes for agricultural planning. The farmers also perceived that scientific weather reporting is faulty (9%), and hardly corresponds to the observed realities and communicates irregularly (7%). With these limitations of conventional weather sources, Bui farmers rely on community elders (45%), personal weather predictions (27%), local weather seers (24%), and friends and neighbors (3%).
Community elders and local weather seers often invoke the gods of the rain through periodical incantations and traditional sacrifices. In Nso land, such traditional sacrifices are performed at the beginning of the planting season, where the gods are invoked for a good agricultural season, before the start of first weeding, harvest, and at the start of the farming season. The first sacrifice to invoke the gods of the land is performed by His Royal Highness the Fon of Nso. This is done at five shrines located at the palace in Kumbo, Mantum in Jakiri, the Kinsaan plunge pool in Kitiwum, the Mairin plunge pool in Takui, and the palace in Kovifem. After the fon’s performance, other traditional leaders do the same in their respective areas of jurisdiction. Such sacrifices entail pouring libation (palm wine), pronouncing incantations and slaughtering goats and chickens, where their blood is sprinkled as sacrifice. The slaughtered chickens or goats are not edible by the indigenes or any other person. The carcasses are allowed in the open air to be devoured by vultures. Indigenous and local practices (ILP) are the result of the application of culture, context and location-specific knowledge to solve local problems. The close relationship of indigenous peoples with their environment makes them vulnerable to the effects of global warming. Indigenous people tend to live in worst places hit by the impacts of environmental change and their poverty exacerbates vulnerability [
5].
3.2. Community Knowledge for Agrarian Weather Forecasting
Community knowledge of weather forecasting is an important component of the concept of ethno-meteorology. It is based on traditional ecological knowledge handed down from generation to generation [
16]. Several variables were chosen in this study to express indigenous community knowledge for planning in the agro-hydrological systems of the Bui Plateau (
Table 4).
The choice of this is because conventional weather information systems are absent, with only five functional stations on the Bui Plateau (Tatum, Takui, Kumbo, Jakiri, and Mbaw Nso). With increasing variability in climate and uncertainty of first rains, most decisions made by indigenous farmers on the Bui Plateau are based on personal experience and conviction (72.2%). As risky as such decisions at the beginning of the planting may be, farmers perceive that the behavior of rains at the onset of the wet season gives them a clue as to how the rest of the growing season will unfold. Erratic nature of rainfall can cause misinformation and mislead farmers to make wrong decisions, given that the dry season is already gradually prolonged. Some signs such are mere smells (51.4%) that indigenous communities rely on to predict whether it going to rain or not at a time is still en vogue.
Some people are gifted to predict the onset of first rains through weather smells, especially in the mornings of the months of February, March, and April. The sounds of some birds and insects is a common indigenous weather forecasting tool in many communities of the Bui Plateau (73.7%). One of such birds is the Senegalese Cowcow, which sings in the morning or anytime of the day to announce rains in about the next 10 to 60 min. On the other hand, the chattering of the Cameroon Mountain Francolin indicates good weather. Insects like crickets cackling at night is an indicator that there will be no rain. Another visible indicator of cessation of the wet season is swarms of dragon flies that fly eastwards from October to November. In the absence of conventional weather forecasting, farmers in the Bui Plateau are able to read weather signs through the behavior of some plants (49.6%). One of such plants is Scadaxus multifluros, which blossoms only once in a year in late February to early March. This plant has been used for generations in Kumbo-Jakiri-Wainamah, Nkum and Oku agrarian basins to read the weather about the onset of the first rains. Once it blooms, the rainy season will begin in about three weeks to one month. A farmer in Shisong affirmed that reading weather signs through the behavior of plants and animals was handed to him by his great grandfather. Indigenous knowledge handed down by forefathers from whom they acquired farming experience have had long standing and proven experience of weather forecast from which they have benefitted. From such experiences, farmers predict rainfall patterns through the farming season. During the dry season, indigenous communities of the Bui Plateau also study the yellowish-reddish atmospheric aerosol loading to make informed decisions about their farming activities.
Aerosol coloring of the atmosphere occurs mainly from December till the start of the wet season. This coloring indicates the appropriate time for farmers to start raising ‘
ankara’ on farms. In the Dzeng-Tatum-Banten basin, raising
ankara (a form of slash and burn) is through the burying of maize stalks for burning. In Mbam valley, ankara is practiced in newly opened fields and in old fields. Bush burning for agricultural activities, pasture regeneration, dry season dust storms are the main sources of local aerosol loading into the atmosphere on the Bui Plateau during the dry season. As from the month of February rain clouds (cumulo-nimbus) start building. Through the gathering of clouds (95.5%) such as a small alto-cumulus and strato-cumulus, community elders, weather seers, and people with experience in reading weather signs can predict the approximate date that the wet season will begin. Other indicators of indigenous weather forecasting include star constellation (60%), extreme temperatures (55.9%) and sequence of yearly weather events to determine what the climate would be in a farming season (42.9%). Dark clouds, according to indigenes signify approaching heavy rain. Ethno-meteorology is a mystery and only some members of the community are gifted in reading and interpreting cloud patterns [
30,
31,
32]. Some of the predictions of ‘cloud watchers’ often miss out and can be very misleading because of changing climatic and environmental conditions. In the Bui Plateau, weather seers are mostly old men of more than 50 years of age who have been practicing agriculture all their life.
3.3. Local and Scientific Weather Knowledge in Agrarian Practices
A local farmer’s ability to make informed decisions is largely governed by personal experiences acquired over the years. In the absence of credible scientific weather information systems to farmers, they must resort to what is at their disposal. Even when scientific weather systems are broadcast on the media, it appears hard to be understood by rural farmers because of low levels of formal education (
Table 5). Daily weather forecast broadcast by the Cameroon Radio Television (CRTV), Spectrum Television (STV), and Equinox TV are faulty. Local weather knowledge is simple to understand than conventional scientific knowledge. Both local and scientific knowledge in weather forecasting over the years are produced through observation, experimentation, and validation.
Scientific knowledge in weather reading follows certain procedures in its production process, but local knowledge is unregulated and haphazard or unorganized by oral tradition. Local knowledge in weather prediction does not require sophisticated tools. Formal education or training is not needed to acquire skills in local weather forecasting. Exercising local knowledge in weather prediction requires no financial investments. Despite yawning differences, scientific weather forecasting and local predictions are mutually exclusive. Local approaches to weather prediction is often accurate and as such are the best in making the right decisions in farming activities. Whereas scientific weather forecasting is purely secular, local knowledge in weather reading entails a great measure of spirituality. Indigenous peoples are among the first to face the direct consequences of climate change due to their dependence on and close relationship with the environment and its resources [
33].
Traditional environmental knowledge has an advantage of being directly linked to household daily activities. It is concerned with the immediate necessities of people’s daily livelihoods and can provide a short-term and immediate solution to a means of survival in the community, making it meaningful [
4,
34]. It may also be useful under transitory conditions, as opposed to contemporary science developed through research and principles for solving global problems without a local origin nor link to social, cultural, political, and physical environment of a specific local area and removed from the daily lives of the people [
18]. Researchers have acknowledged the dynamism of local knowledge in providing solutions and coping with new environmental and economic hardships in society [
20,
35], with further acknowledgement that some local farmers have succeeded in their farming systems by combining local farming methods with scientific knowledge [
36,
37].
Scientific approach to weather forecasting should only be supplementary to local approach in making farming decisions. Scientific analysis of climatic data and indigenous perceptions recorded in this study shows some convergences. There are problems that hinder the synergies of indigenous traditional local knowledge with contemporary science in the management of resources, such as differences in power relations between developed and developing countries. This is aggravated by limited integration techniques which are exacerbated by the lack of proper background in local knowledge, lack of realization that indigenous traditional knowledge has values attached to local content touching the life of the local people and could contribute to the development of sustainable climate change, mitigation, and adaptation strategies and lack of proper understanding on how local knowledge could be used in dealing with environmental issues hence solutions to developmental problems [
37,
38]. Despite the positive features of indigenous traditional knowledge, there are doubts that question the legitimacy of the knowledge in managing agriculture, while many farmers still suffer from food shortages and increased environmental degradation [
13]. There are other factors that are embedded in food production that farmers encounter such as imported food, abrupt and prolonged occurrence of natural hazards such as floods, drought, and windstorms that most rural farmers are not able to cope with [
20,
39], as well as the misguided notion that all indigenous practices are unproblematic and would be a panacea to all small-scale farming and nature related environmental problems because they are local in origin [
40].
3.4. Agro-Hydro-Ecological Indicators of Climate Variability in Bui
The relationship of humans with the Earth’s environment has changed throughout the evolution of Homo sapiens and the development of societies [
41,
42]. Apart from climate change, the environment at the local scale of Bui Plateau has witnessed changes in weather conditions, the ebbing of streams and shrinking water resources, loss of rich tropical montane forests, land degradation from overgrazing, and accelerated erosion on arable land. These dramatic changes are within the framework of
‘anthropisation’ given that man has become a robust geophysical agent during the Anthropocene Era [
43,
44]. The impact of human activity in the Bui Plateau has perturbed the delicate steady state of nature. This has greatly reduced the resilience of livelihood and life support systems. From 1970–1979, the agrarian system in the Nkar-Kumbo-Kikaikom basin was characterized by flat ridging, high coffee prices, massive deforestation to establish new farmlands, and planting of eucalyptus (
Table 6).
There was regular onset of first rain in mid-March. Water resources were abundant and there were hardly noticeable environmental changes. With the fall in coffee prices in the mid-1980s, farmers eliminated their coffee farms and transformed them into eucalyptus plantations and for food crop farms. Rainfall was regular with the onset rainy season occurring around mid-March. The drought of 1983–1984 raised caused much agitation in farming communities. With these, there were still no major changes in water resources. The drought of early and mid-1980 caused minor environmental changes like drops in crop production.
From 1990, there were already remarkable drops in food production, which initiated the advent of chemical fertilizers application. The onset of first rains became irregular and extreme weather events like dry spells, stormy weather, and floods increased. In July 1998, hail stones destroyed crops and over the Bui Plateau. Water levels dropped remarkably in local streams. The inhabitants could already perceive that their livelihoods were vulnerable to changing environmental conditions. The Strategic Humanitarian Services (SHUMAS) initiated the eucalyptus replacement project to save watersheds from the overwhelming effects of eucalyptus plantations. From 2000, reasonable food crop production for maize could only be boosted by application of chemical fertilizers. Temperatures plunged and the onset of first rains became very irregular. Mounting water scarcity became a daily reality, leading to the emergence of water scarcity problems. [
45,
46] affirmed that rapid urbanization and poor water governance are threats to water security in Kumbo town. From 2010, an innovation in the agricultural sector was the increased use of herbicides (spray weeding). Pests like caterpillar invasions also became regular during the early growing seasons. The 1970s, in the Nkum basin, were characterized by long fallow periods, low population growth, and thick natural forest from Nkum Kov to Banten.
Other pockets of natural forest cover are at Kov Mven, Kovifem and Takui. Rainfall was regular with onset of first rains in mid-March. Like Nkar-Kumbo-Kikaikom basin, water resources were abundant, and people could hardly perceive any environmental changes. The 1980s were characterized by massive deforestation and the emergence of large-scale eucalyptus plantation all over the landscape (watersheds, fertile lowland plains). With the slumping of coffee prices at the world market and the closure of the West Cameroon Marketing Board, farmers, transformed coffee farms into cultivable land and eucalyptus plantations. The emergence of eucalyptus plantations at head waters caused noticeable drops in spring yields in the late 1980s, thereby leading to vulnerability of water resources to environmental change. With increasing population, fallow periods dropped significantly, necessitating the use of chemical fertilizers to boost crop output. The onset of first rains became irregular, characterized by frequent dry spells and stormy weather, leading to a drop in water levels in streams. To address degradation of watersheds, SHUMAS embarked on the eucalyptus replacement project, through cutting down of eucalyptus and replacing with eco-friendly species like maesopsis, pronus, polysia, vitex, and cordia. Between 1996 and 2005, over six million environmentally friendly trees have been planted in Bui and Donga Mantung Divisions through SHUMAS’ eucalyptus replacement project. Recent weather patterns and a changing climate have led to severe water scarcity and vulnerability of livelihoods system to environmental changes. Tatum, the headquarters of Nkum Sub-Division is reputed for water shortages all since 1980s.
The Nkuv-Ndzeen agrarian basin is one of the areas of drastic anthropisation in the Bui Plateau. In the 1970s, this frontier zone was characterized by thick cover of tropical savannah transition forest, with a normal seasonal hollow frontier and transhumance phenomenon. Like in the other basins, rainfall was regular with the onset of first rains in mid-March. There were relatively clean natural streams. The environment was relatively stable. In the 1980s, the basin was transformed into a sedentary frontier (a new permanent farming area). Rainfall was still regular with the onset of first rain in mid-March; though there were signs of extreme weather events such as the droughts of 1983–1984. With increasing anthropisation, there was massive deforestation, accelerated erosion in agricultural land, which led to sedimentation of water bodies. In the 1990s, intensive agriculture and grazing caused massive forest loss, leading to a decline of water resources indicating high vulnerability of human and environmental systems. From 2000–2009, this area became a sedentary basin for agro-pastoral activities, characterized by frequent cultivator-grazier conflicts, which have been persisting. The persistence of cultivator-grazier conflicts is because these activities are not compatible in the same area. Severe land degradation has transformed the landscape into desert-like conditions leading to complete loss of surface vegetation and the development of bad lands. Between 2010 and 2018, frontier settlements like Nkuv, Bamkov, Ndzeen, and Gwarkang suffered from fuel-wood crisis, water scarcity and highly susceptible to landslides, prolonged dry seasons, and a host of other environmental stressors.
The Mbokam-Ngomrin-Mbaw Nso area was traditionally a hollow frontier like the Nkuv-Ndzeen basin. In the 1970s, regular onset of first rains and stable environmental conditions were the norms. In the 1980s, the area was transformed into a sedentary basin in the same vein as Nkuv-Ndzeen. The drought of the early to mid-1980s led to disturbances of the natural state of the environment with shrinking of water resources. With the low-lying nature of this area, rice culture was experimented in the 1990s, which became an additional agrarian practice. Irregular onset of the first rains continued, leading to frequent cultivator-grazier conflicts. Water resources continued to shrink, leading to vulnerability of agrarian systems to climate variability and change. From 2000, there has been decreasing drop in maize and beans cultivation. Cultivator-grazier conflicts have also intensified. Flooding and other environmental stressors have increased leading to high vulnerability of agro-hydrological systems to changing environmental conditions.
The Djottin-Nkor-Lasin plain located north-west of the Bui Plateau is an eastern extension of the Donga-Plain. In the 1970s, there was abundant crop output, lush tropical highland forest cover, regular onset of first rains in March, and overflowing springs and springs. Like the Nkum area, there was massive elimination of coffee farms in the 1980s due to slumping of the coffee prices at the world market. The drought of the early to mid-1980s caused people to know that environmental changes were occurring. When food crop started dwindling in the 1990s, farmers resorted to the use of chemical fertilizers. The Bamti area also attracted graziers. As a result, Bamti has become one of the hotspots for cultivator-grazier conflicts. From 2010, uncertainty of weather patterns became regular. The inhabitants also faced water shortages as an indicator of climatic and environmental stressors.
The Oku-Vekovi-Tadu basin is a highland agrarian basin. In the 1970s, the area was covered by thick montane forest of the Kilum Ijim. Agricultural output was abundant. There was regular onset of first rains at mid-March, with high yielding springs and a relatively stable environment. In the 1980s, there was massive deforestation of the Kilum-Ijim forest due to population increase and the need for increased food production; the destruction of springs and disturbance of the natural state of the environment. In the late 1980s, conservation measures were put in place and enforced by legislation. A few community forests were created around the Kilum-Ijim like Ijim, Upper Shinga, Mawes, Kedjin, Emfeh-Mii, Nchiy, Mbai, and Bihkov (Vekovi). There is also a plant life sanctuary in Elak-Oku. Despite these measures, water crisis has become the order of the day in Oku because of population growth, ailing infrastructure, climate and other environmental changes. Population increase has been progressive in Oku against a backdrop of declining resource base.
The Mbiame agro-ecological basin has witnessed its own share of agro-hydrological changes since the 1970s. The 1970s were characterized by stable conditions through abundant overflowing streams, regular onset of first rains in mid-March, abundant crops output, longer fallow periods, shifting cultivation, and large expanses of tropical highland forest like the Mbiame forest. Changing environmental conditions in the early to the mid-1980s like droughts and the slumping of coffee prices pushed farmers into the Mbiame forest to open new farmlands. Despite this, there were no discernible changes in water resources. By the 1990s, agricultural output was already dropping, and farmers embraced the application of chemical fertilizers to boost production. The Mbiame forest continued to vanish, while farmers were experiencing high temperature and irregular onset of the first rains. With increasing threats of climate change and environmental degradation, some NGOs like the Centre for Nursery Development and Eru Propagation (CENDEP) and Green Care Association (GCA) stepped in to restore the Mbiame forest through soil and water conservation.
A common trait in all the basins is that the local agro-hydrological system has changed over time, though the indigenes of the Bui Plateau perceive mostly negative changes. Farmers perceived that the 1970s were characterized by flat ridging, regular onset of first rains in mid-March, massive deforestation, high coffee prices, planting of eucalyptus, severe droughts (extreme weather events) and abundant water resources. Agricultural intensification has brought major environmental changes on the Bui Plateau. Kishong village, for example is known to have been carpeted with natural forest up till the 1970’s. With increasing population and the need to feed and accommodate the additional mouths, these forested areas were transformed into farmlands. In Kumbo central, there has been rapid population growth. Within the Kumbo urban space, there is land use competition for functions such as residential, commercial, and agricultural. This often leads to conflicting interests, thereby creating environmental problems within the urban space [
47]. Some fallowed pieces of land are now occupied by eucalyptus. Along the Kuvlu-Banten range, there has been rapid deforestation, thereby turning natural forests into savannahs. These changes increase the vulnerability of agro-hydrological systems and weaken adaptive capacities. These systems interact with each other, so there is need to maintain them all to underpin human well-being. Global impacts and associated risks to humans are already evident for climate change, biosphere integrity, biogeochemical flows and land-system change. By 2012, the equivalent of 1.6 Earths was needed to provide the natural resources and services humanity consumed in one year [
48]. Rapid and unsustainable cultivation has also intruded into natural forest patches around the Kovifem Fon’s Palace, Kifem, Takui, Mount Oku, Mbiame, Nkuv, Kov Ndzeen, and montane forest communities of Nkum-Kov. Another agricultural practice is human intrusion in wetlands along stream flood plains. Along the Mairin valley, stretching from Mbimtsen are artificial levees constructed about 1 m high and 1 m in width to contain floodwaters from destroying crops during the rainy season. In some places like Takui, Kaiy, Kishong, some stream channels have been straightened and even diverted to cultivate vegetables and solanum potato during the dry season. These practices are also feasible in the Mbim valley at Ngondzen and Nseh.