4.2. Anthropogenic Pressures and Extent of the Hierarchical Changes in the Spatio-Temporal Pattern of Deforestation in Lualaba Province
Our results indicate significant expansion of savannas, agricultural fields, and urban areas in Lualaba Province, driven by abundant natural resources like fertile soils and mineral-rich deposits, including copper and cobalt [
36]. These resources have attracted investments in agriculture and mining, leading to the growth of these sectors [
18,
69]. Similar patterns were observed in southern central Angola [
70]. Additionally, improved road networks have facilitated access to rural areas, further promoting agriculture and mining [
14] and stimulating urbanization by enabling rural populations to migrate to urban centers for employment and services [
18]. In Mekelle, Ethiopia, a favorable investment climate has similarly driven rural-to-urban migration, increasing demand for urban land [
71]. The growing national and international demand for rosewood and mining products has fueled expansion in these sectors [
69,
72,
73].
The need to expand agricultural land to meet rising food demands has led to the conversion of forests into maize and cassava fields, as observed in the Katangense copperbelt [
18,
74]. Both large- and small-scale mining operations have also contributed to deforestation for mining infrastructure and extraction [
14]. Unplanned urban expansion has converted forest lands into residential, commercial, and industrial zones, leading to habitat fragmentation and loss. In the Lubumbashi plain, Cabala et al. [
68] reported the conversion of 177.5 km² of forest to bare soil and settlements between 2005 and 2011. Economic challenges have forced populations to build makeshift housing in forest-adjacent areas with limited infrastructure, often prioritizing immediate survival over resource sustainability.
Our results show that the extent of deforestation is linked to the socio-economic and political context of the province. The period of socio-political instability in the DRC (1990-2001) was marked by several factors that had a significant impact on agriculture, urbanization, and consequently reduced the extent of deforestation [
66]. Indeed, political instability created an environment of insecurity and farmers faced challenges accessing land, agricultural inputs, and markets, leading in disorganization of agricultural production systems. Barima et al. [
75] found that there was minimal growth in cocoa cultivation during a period of political turmoil in Ivory Coast, leading to a reduced rate of deforestation. Additionally, limited investments in urban infrastructure due to precarious political situations slowed down the development of urban areas in the Lualaba province, echoing the results found by Useni et al. [
76] in the city of Lubumbashi. Basic services such as electricity were inadequate, discouraging new populations from settling in urban centers [
77]. Regarding deforestation, political instability limited economic activities such as large-scale logging, consequently foreign investments in this sector decreased [
78], confirming the findings at the national level, which showed that the deforestation rate halved when comparing the period of political crisis (0,08% from 1990-2000) and the post-crisis period (0.16 from 2000-2010) [
79].
However, the liberalization of the mining sector in 2002 has generally led to an increase in large-scale mining operations, particularly for minerals like copper and cobalt. The rise in the quantity and size of mining sites has caused fragmentation of vegetation in the Lualaba province [
19]. But, a trend in the decrease of deforestation extent was observed during the period following the global financial crisis (2008). Indeed, a reduction in mining activity was linked to a decrease in demand for forest lands for mining infrastructures, potentially leading to a decline in the deforestation rate. Globally, during the financial crisis period, deforestation rates in Asia, Africa, and Europe decreased by 83 %., 43 %, and 22 %, respectively [
80]. Additionally, the establishment of the new province in 2015 increased the deforestation rate, particularly due to the infrastructural development, urbanization, and expansion of economic activities that added additional pressure on forest resources [
18]. In a new province where the majority of the population is poor and access to electricity is low, the exploitation of forest resources for charcoal production has become an excellent refuge sector [
77]. It’s also worth noting that charcoal is an essential energy source for cooking and heating [
81], and therefore its constant demand by households in the province’s main urban areas ensures a certain economic stability for producers [
68]. Yet, the carbonization yield remains low in the region [
82].
Our findings revealed that deforestation occurs through the fragmentation of forest patches, confirming the results of previous studies [
16,
18]. Indeed, forests ecosystems are generally fragmented into smaller patches by roads and infrastructure development, expanding agricultural areas, and urban zones [
83]. This fragmentation can lead to a simplification of the shapes of residual fragments as intact areas of natural forests become increasingly scarce [
84]. As anthropogenic pressure intensifies while forest resources are becoming scarce [
85], the remnant forest patches subsequently disappear, as found in the Lufira Biosphere Lufira [
24]. Conversely, savanna patches merge into the landscape due to factors such as extensive agricultural practices, charcoal production and bushfires [
17]. Indeed, agricultural activities whether preceded by charcoal production or not and bushfires can gradually transform forest areas into savannas [
86,
87]. The exploitation of forest resources for charcoal production can lead to the conversion of forests into savannas due to intensive tree cutting for charcoal, resulting in reduced forest cover [
88]. The expansion of agricultural fields typically involves creating new patches rather than enlarging existing ones due to increasing land demand. As soil fertility declines, farmers shift to new plots, continually creating cultivated areas and exerting ongoing pressure on forest resources [
89]. The ongoing decline in tree abundance facilitates light penetration, promoting the growth of herbaceous species [
90]. This often leads to the formation of savannas, explaining their increasing presence in the landscapes of Lualaba Province. Malaisse [
20] supports this trend, noting that savannas are anthropogenic in the region, expanding in tandem with landscape disturbance levels.
In the context of uncontrolled urbanization, acquiring new land often proves simpler and more cost-effective than densifying existing urban areas. Densification typically necessitates complex land regularization processes and substantial infrastructure investments, making it a less attractive option for rapid urban expansion [
91]. This phenomenon is especially prevalent in regions with minimal urban development, such as the DR Congo. In these areas, urban growth is frequently concentrated around mining sites, where construction on bare soil is relatively straightforward [
21]. However, this practice can exacerbate human exposure to environmental hazards, including trace metals, which are commonly present in the soils around mining operations [
92]. Consequently, uncontrolled urban expansion not only contributes to inefficient land use but also poses significant health risks to the population.
Deforestation is generally more severe in areas practicing shifting cultivation compared to mining regions. Shifting cultivation, or slash-and-burn agriculture, is a traditional practice in DR Congo involving the periodic cutting and burning of forest plots for crop cultivation, leading to temporary and recurrent deforestation [
93,
94]. This can result in land degradation and pressure on protected areas due to inadequate monitoring [
24,
67,
95]. Agricultural areas are more accessible and less regulated than mining zones, which are managed with stricter environmental controls and regulations [
69]. Consequently, agricultural lands are more prone to deforestation driven by local economic interests [
96]. Despite their protected status, forest cover in these areas declines due to poor management, demographic pressure, and illegal activities [
95]. Corruption and enforcement challenges exacerbate this issue. Studies in the DR Congo, Zambia, Ghana, and Burkina Faso confirm that agriculture is a leading cause of deforestation [
97,
98,
99].
Deforestation rates in this study significantly exceed the national average of 0.4% per year. The rate in Lualaba province is higher due to intensified logging, agricultural and mining expansion, illegal activities, and weak forest governance. Despite national conservation efforts, local factors contribute to higher deforestation in provinces like Lualaba. Deforestation varies with spatial scale: protected areas face intense pressure from subsistence agriculture, artisanal mining, and fuelwood collection, compounded by outdated monitoring resources [
100]. This situation mirrors issues in Kasenga [
101], Butembo [
102], and Zambia [
103], leading to severe deforestation in areas like the Lufira Biosphere Reserve [
24]. At larger scales, commercial agriculture and mining drive deforestation, though conservation measures at provincial or national levels can mitigate these effects [
19,
104,
105].
The results indicate that, regardless of the scale of analysis, the density of forest edges increases, including the average distance between neighboring patches, alongside a decrease in the size of the largest forest patch. This trend is primarily driven by habitat fragmentation, often resulting from urban expansion, agriculture, and mining activities [
54,
55]. As new edges are created, the number and density of forest fragments increase, while the size of continuous forest areas decreases. On one hand, forest fragmentation can enhance habitat diversity by creating various microenvironments along the edges. But generally, it has significant negative effects: the loss of continuous habitat can threaten biodiversity by isolating species populations and disrupting migration corridors [
84]. Additionally, edges may be more susceptible to disturbances such as storms and invasions by exotic species [
106]. The consequences of this fragmentation include a reduction in the resilience of forest ecosystems to climate and environmental changes. Furthermore, the decline in large forest patches limits the ability of ecosystems to provide essential services such as climate regulation, biodiversity conservation, and carbon storage [
55,
84].
4.3. Implications for the Conservation of Landscape and Forest Ecosystems in Lualaba
Agriculture-oriented territories are highly susceptible to deforestation, even in protected areas. To address this, policies must promote sustainable land management, including reforestation and ecosystem restoration with indigenous species, as well as financial incentives for sustainable agriculture. Efforts to increase carbon stocks through forest restoration could potentially restore 700 million hectares globally in the next 50 years [
107]. For instance, the agroforestry project near Lubumbashi has successfully planted 350 hectares of degraded land with
Acacia auriculiformis [
108]. Local governments should establish buffer zones around protected areas to curb agricultural expansion while encouraging environmentally friendly farming practices. Integrated territorial planning is crucial to prevent inappropriate land conversion for urban or agricultural use. This requires collaboration among local authorities, farmers, urban planners, and ecologists to create balanced development strategies.
Collaborative management between state wildlife agencies and NGOs can attract investment and enhance protected area performance [
109]. Additionally, agricultural reserves with regulated and sustainable practices can help mitigate deforestation from intensive agriculture. These reserves must be managed collaboratively, addressing limitations of current land allocation models controlled solely by local customary authorities [
73].
For extremely poor populations, adopting sustainable agricultural practices is crucial. Techniques such as agroforestry, crop rotation, and water conservation can enhance productivity and minimize deforestation. For instance, on the Batéké plateau in Kinshasa, 8000 hectares of
Acacia auriculiformis plantations produce 8000 to 12,000 tons of charcoal annually, along with 10,000 tons of cassava, 1200 tons of maize, and 6 tons of honey [
110]. Improving agricultural practices through the use of adapted seeds, integrated pest management, and crop diversification can reduce forest pressure and support ecosystem preservation. For example, using improved maize varieties and recycled human waste in Lubumbashi has enhanced crop growth and nutrition, leading to higher maize yields compared to inorganic fertilizers. Creating corridors with native species, like the Ambositra-Vondrozo Corridor in Madagascar, can also improve ecological connectivity. This corridor, spanning 200 km and covering 1,352 km², links two major national parks, Ranomafana and Andringitra, facilitating species movement and genetic flow between forest patches [
111].
Local communities must be actively engaged in natural resource conservation to combat deforestation effectively. The lack of local involvement in forest conservation efforts has been a major factor in deforestation in the Lubumbashi region [
85]. In contrast, strong community participation has facilitated forest regeneration in Burundi’s Bururi region [
112]. To promote sustainable practices, awareness programs, environmental education, and capacity-building initiatives are essential [
113]. Although governance challenges can complicate these efforts, partnerships with international organizations and NGOs can provide necessary financial and technical support [
114,
115]. Media campaigns and targeted educational programs can further raise environmental awareness [
116].
Strengthening environmental legislation and ensuring rigorous enforcement of regulations are crucial for protecting sensitive forest areas and curbing unsustainable activities [
117]. This includes enhancing monitoring within protected areas, implementing strict access and land use measures, and imposing penalties for illegal deforestation. For example, in the Forest Reserve of Bururi, forest area increased due to restrictions on human activities, reduced agricultural disruptions, and more forest rangers [
112]. Addressing poor governance and corruption requires robust transparency and accountability mechanisms to ensure effective monitoring and management within protected areas [
118,
119].