*3.1.1 Oil palm cultivation and deforestation*

Ecology of the oil palm shows that the forest area has the suitable conditions (soil, rainfall, temperature, relief and insolation) for its development. It is in this vein that all old and new palm plantations (from all actors being agro industries, small farmers and elites) are located in forest areas. This is because forest milieu guarantees them a sustained production over a long period while others areas like fallows and abandoned farms do not bring the expected results (**Figure 2**).

It is worth notice that agro industrial palm plantations/concessions and properties are 100% created on forests. The areas of industrial oil palm producers increased from 46,850 ha in 2009 to 63,200 ha in 2014 and more than 176,600 ha in 2019. It means 35% increase in about 5 years and 73% in 10 years. Similarly, remote sensed data in Ngwéi and Ekondo-Titi Sub-divisions show that more than 83% of smallholders palm plantations were created in both primary and secondary forests. Increase in smallholders palm plantations is estimated at more than 50% in 10 years between 2000 and 2010. The latter do no longer used fallow land and other abandoned fields. Because there are so many smallholders actors more than 90% for only 15% of area, the accelerated deforestation process by atomizing the forest. Atomization of the forest by unsustainable oil palm worsen practices (construction or building, clearing, palm plantations and wasteland) contributes enormously to the decline of the forest which is suffocated. Any parcel of forest located between two or more of these plots is doomed to disappearance.

The threat of palm plantations on the original forest is all the more serious as certain industrial concessions granted in recent years are adjacent to protected areas. This is the case of Sithe Global Sustainable Oils Cameroon (SGSOC); a subsidiary of the American multinational Herakles Farms. The concession acquired by the latter is located near protected areas (Korup and Mounts Barossa national parks, Rumpi hill reserve and Banyang-Mbo fauna sanctuary) recognized as High conservation value forests (HCV) and also endemic for its biodiversity. The same situation was observed in the Greenfil case whose palm plantations are located very

#### **Figure 2.**

*Type of land use chosen for the creation of oil palm plantations in the main production basins (Source: field survey 2013–2020).*

close to the Ebo forest which plays host to a wide variety of wild animals, especially the western gorilla, the Nigeria-Cameroon cross boarder chimpanzees, drills and several other primates as well as many endemic plant species. Another case is the 2019 de-gazettement of Forest Management Unit (FMU) number 09–025 near the famous Campo Ma'an National park for its transformation into oil palm (60,000 ha) plantation by CAMVERT. This National Park is recognized as Model forest and Biosphere Reserve. The proposed declassified area encompasses two blocks covering 40,000 ha to the north and 20,000 ha to the south bordering Dipikar Island (Campo Ma'an National Park) where there is a gorilla habituation project ongoing.

Deforestation caused through palm planting also fragments the habitat of endangered species and disturbs wildlife corridors usually used by forest elephants. Such a situation bring confusion and more and more anger, disappointment and land conflicts due to ambiguous governance of the forest. This issue is discussed in the following paragraph.

As the ecological impacts are concerns, there is a high degree of confidence that the expansion of palm oil cultivation has resulted in deforestation. Numerous authors and reports have emphasizes on oil palm as a driver of deforestation and land-use change in tropical countries [20]. Globally, oil palm crop development is responsible for less than 0.5% of deforestation, but in parts of the tropics this figure can reach 50% [21]. For Indonesia, the proportion of direct and indirect deforestation linked to the expansion of elaeis farming is estimated to be between 11% (2000 to 2010) and 16% (1990 to 2005). At the same time, in 2016, in the same country, 45% of oil palm plantations were on land which, in 1989, was forests [22, 23]. This phenomenon is very marked in Malaysia and Indonesia because they are the two largest palm oil producers in the world. With an average forest loss of 350,000 hectares annually, deforestation is particularly dramatic on the island of Borneo, where about half of the deforestation between 2005 and 2015 was directly linked to industrial oil palm plantations [21, 24]. As shown by [25], 2/3 of deforestation in the South-West region of Cameroon during the same period was caused by the expansion of oil palm farms and the installation of new actors. The peculiarity of oil palm basins areas compared to the rest of Cameroon is that they host most of the agro-industrial activities (oil palm, rubber, plantain and sugar cane). To this should be added the share of deforestation generated by small producers, which is still unclear. In addition, oil palm plantations are responsible for significant greenhouse gas emissions.

## *3.1.2 Elaeiscultivation and the loss of biodiversity*

The establishment of palm plantations generally involves the almost total clearing of the forest. This leads to the loss of species, including those that are endogenous in certain areas of high conservation value. Oil palm is generally grown in pure culture. It doesn't tolerate association with other commodities. The other species found in palm plantations are generally the ombrophilous grasses. **Table 4** built with quadrates and transects methods, shows the numbers of species, families, and individuals recorded in the oil palm cultivation basins of Ngwéi and Ekondo-Titi compare to those of protected areas bordering these basins. One can observed that less than half of the species present in humid forests are present in industrial plantations. It is the same for the number of families which decreases between the mangroves and different forms of palm plantations. From the table below, smallholders palm plantations conserve their biodiversity better than industrial one. This is explained by the solicitation of other ecosystem services such as traditional pharmacopoeia and the harvesting of non-timber forest products by populations.

From the **Table 4** above, out of the 18 families in moist and dense forest and 20 families in the mangrove, only 5 families are found in all palm plantations (village,


#### *Environmental Impacts of the Oil Palm Cultivation in Cameroon DOI: http://dx.doi.org/10.5772/intechopen.97862*

#### **Table 4.**

*Floristic diversity between palm plantation and forest of Ngwéi and Ekondo Titi subdivisions and some protected areas around Kribi and campo.*

elitist and industrial). These include *Annonaceae, Apocynaceae, Euphorbiaceae, Fabaceae* and *Loganiaceae* as well as *Moraceae* found in wet and dense forests and in the elitist and villager oil palm plantations and *Phyllanthaceae* found in the mangroves and in the elitist and smallholders plantations. This constitutes either a real quantitative and qualitative decrease in biodiversity outside the *Fabaceae* families. The number of families, however, increased in the elitist (25) and smallholders (24) oil palm plantations of Ekondo-Titi. In protected areas and FMU, families range from 26 to 36 meaning that oil palm is a driver of deforestation. Therefore, the least diversified plots are the smallholders' farms, followed by industrial and finally elitist palm plantations. This can be explained by the regular maintenance of industrial palm plantations, the mixed food crops grown in some village palm plantations and the irregularity of the maintenance in the elitist oil palm plantations.

Conclusively, the clearing of hundreds or thousands of hectares of land for oil palm cultivation is one of the most important factors in the destruction of vegetation cover and consequently of biological diversity. Deforestation and degradation are the root cause of a considerable loss of flora species, fragmentation and disturbance of the natural habitat in these areas. The original evergreen natural forest has disappeared in favour of the mono-specific oil palm plantations, which occupy three-tenth of the territory, but catalyse deforestation. Also, aggressions on forests and fallow lands for oil palm establishment create enormous pressure on traditional and modern land reserves and protected areas.

#### *3.1.3 Floristic diversity index*

The measurements from quadrates and transects allow to calculated many indices. The Simpson index which measures rare species is roughly equal across the four project sites. The equitability of Pielou, which provides information on the distribution of species, is approximately equal in the different sites sampled. The Shannon index, which takes into account floristic diversity, is higher in PNCM (4.01) and similar in PMK, PNDE and UFA (**Table 5**). The Shannon index (**Table 5**) shows significant biological diversity for dense forests and for mangroves (0.28). The Shannon index is also high for the industrial palm plantation of Ekondo-Titi, relatively less for the village palm and elitist palm plantations. The Simpson index is 0.08–0.09 in mangrove, moist and dense forest compared with 0.07 in the industrial and elitist palm plantations of Ekondo-Titi against 0.01 in the smallholders and elitist palm plantations of Ngwéi. Simpson index shows the degree of land use in the two districts. This is due to the fact that ecosystems are profoundly affected by agricultural practices and especially by oil palm cultivation (and even cocoa farming with exotic species), which reduces density and specific diversity locally.
