Colombia is a megadiverse country, home to 314 types of ecosystems and many areas of high biological diversity [Convention on Biological Diversity (CBD), 2022]. The Orinoco eastern high plains (OHP) region is a critical area for social and economic development due to its potential for agricultural expansion. While approximately 156 types of ecosystems are found across the 34,720,853 hectares of the Colombian Orinoco basin (Bustamante, 2019), many of these ecosystems are degraded due to land clearing, with devastating consequences for biodiversity. The OHP encompasses about 10 million hectares in Meta and Vichada. The OHP is part of the savanna biome, and biogeographical studies recognise it as an independent geographic unit for plant communities [Instituto Geográfico Agustín Codazzi (IGAC), 1997; Morrone, 2014; González-Orozco, 2021].

The OHP is characterised by landscapes of well-drained natural savannas, gallery forests, rivers and lagoons that harbour a rich assemblage of species, including 144 endangered and 75 endemic species (Deutsche Gesellschaft für Internationale Zusammenarbeit GmbH [GIZ]; Correa et al., 2006; Rosselli et al., 2022). However, the biodiversity of the OHP is under threat due to large-scale and rapid transformation of ecosystems by agriculture, primarily agroindustry (Andrade et al., 2013; Baptiste et al., 2017; Etter et al., 2020). With vast areas of agricultural frontier classified as a priority for water and forest conservation, understanding the extent of usable land for sustainable human use is challenging. Thus, knowledge of the spatial relationship between biodiversity and agricultural expansion is essential for effective agricultural and environmental policy planning in Colombia’s OHP.

The ecosystems of the OHP are characterised by vast grasslands, wetlands and savannas, which are suitable for livestock farming and agriculture. Cattle ranching is the most important agricultural activity in the region, with over 20 million head of cattle being raised for meat and dairy production. The region is also home to significant areas of oil palm and soybean plantations, which have been expanding rapidly in recent years. Other crops grown in the region include corn, rice, cassava and sorghum.

The OHP also known as the ‘Llanos Orientales’, are characterised by a unique flora and fauna that have adapted to the hot and dry climate of the region. One of the most iconic species of the Llanos is the capybara, the largest rodent in the world, which can be found living near the many rivers and lagoons that run through the region. Other common mammals include deer, jaguars and various species of monkeys. The area is also home to a variety of bird species, such as the scarlet ibis, the jabiru stork and the king vulture, making it a popular destination for birdwatchers. The vegetation of the OHP is mainly composed of grasslands, shrubs and trees that have adapted to the region’s harsh climate, including species such as the Moriche palm and the Yopo tree, which are important to the local indigenous communities for their medicinal and cultural uses. The spatial distribution of many of these flora biodiverse groups are poorly understood in the OHP of Colombia. Consequently, there are profound sampling gaps due to remoteness. Therefore, we need to generate flora and fauna datasets of the OHP and analyse its spatial patterns of species richness and endemism. Richness is important because we can find out where are the greatest number of species. Endemism otherwise refers to how much range restricted are the species.

The biodiversity of the OHP is scarcely studied and under threat due to the large-scale and rapid transformation of ecosystems by agriculture, principally agroindustry (Lavelle et al., 2014; Rosselli et al., 2022; Villegas et al., 2022). In the OHP, many areas are inaccessible and remote, which is one of the main challenges regarding biological surveys and biodiversity analysis. Even the most accessible bioregions of Colombia, such as the Andean biome, experience sampling biases (Vargas et al., 2022). While the Andean bioregions are well studied, due in part to their accessibility, understanding of the more remote, OHP region is lacking. Specifically, data on species distributions and its relationship to agricultural expansion is critically needed to improve understanding of the human impacts on agrobiodiversity. Such knowledge is essential for the effective planning of agricultural and environmental policy in Colombia’s eastern plains. Consequently, if this complex land-use change phenomena and the lack of biological records continue, it will likely lead to biodiversity loss and irreversible changes in the ecosystem’s integrity.

We argue that biodiversity in the OHP requires a better understanding of its spatial relationships to agricultural expansion. The OHP is considered Colombia’s future food basket due to its large, underutilised territories with the potential for cropping. However, a variety of classifications generate different areal estimates. According to GIZ, the agrarian land use area of underutilised crops suggests that around 16 million hectares are apt for 27 sustainable agricultural systems across the whole Orinoquía region [Deutsche Gesellschaft für Internationale Zusammenarbeit GmbH (GIZ), 2020a]. These areas are different to UPRA’s classification because they use other criteria such as ecological structure. For estimates of potential agricultural areas, here we rely mainly on UPRA’s classification. On the other hand, UPRA states that Meta has close to 5 million hectares and Vichada 4.7 m/h apt for developing the agricultural frontier [Unidad de Planificación Rural Agropecuaria (UPRA), 2021].

Thematic maps of crops were generated by Unidad de Planificación Rural Agropecuaria (UPRA) (2021) based on national, regional and local data census for all municipalities in the Orinoquia region. As a result, optimal, marginal and not suitable areas for agriculture were identified. They estimated that about 15.9% of all land in the Orinoquía region is suitable for livestock production and 10% (2.3 million hectares) for agroforestry and forestry systems. Of these, just 1.3 million hectares are suitable for agricultural expansion in Meta department. However, just 1.07 million hectares should be used for agricultural production. In the case of Vichada, 10 million hectares are projected for agriculture, including livestock. Of those, just 1.4 million hectares are recommended as apt for agricultural production.

The agricultural practices in the OHP of Meta and Vichada are heavily influenced by the region’s climate, which is characterised by a wet season and a dry season. During the wet season, which lasts from April to November, the grasslands and wetlands provide abundant grazing for livestock, while crops are planted and harvested during the dry season. Regarding specific farming activities, cattle raising is the primary source of income for the inhabitants, and the predominant food systems are pastures, agroforestry and livestock. The problem is that land use changes caused by agriculture in the OHP are happening fast across the whole eastern plain’s region degrading its native biodiversity and therefore compromising its conservation. Hence, studies investigating the spatial changes between biodiversity and the agricultural frontier are needed.

Besides agricultural expansion and biodiversity loss, the region faces several challenges, including soil erosion, deforestation and the need for improved irrigation and water management systems. Climate change is also a growing concern, as droughts and flooding events have become more frequent in recent years.

To address these challenges, the Colombian government and private sector have been working to promote sustainable agriculture practices, including the use of conservation agriculture techniques, improved water management and the expansion of agroforestry systems. These efforts aim to promote sustainable development and ensure the long-term viability of agriculture in the region. However, lack of science-based information is still a common issue in the region. Here we apply a framework that uses the distribution of existing species records of fauna and flora in the OHP areas where high levels of biodiversity (single hotspots or regions) are found, and agricultural expansion occurs. This approach aims to enable policymakers, civil society leaders and businesses to identify spatial changes of agrobiodiversity and mapped out priority areas of biodiversity to inform regional planning. Therefore, our paper will contribute to bridge the gap knowledge between biodiversity and agriculture in the OHP that could be used to improve environmental planning.

Our results present new evidence that could be considered an early warning that hotspots of biodiversity in the OHP are under pressure due to agricultural expansion (Figure 5). A new action plan to map out the less vulnerable areas and more suitable lands for safe and sustainable future agrarian development in Puerto López, Puerto Gaitán, Santa Rosalía, La Primavera and Puerto Carreño will be required to address this challenge.

We suggest that each municipality plan its sustainability policy and agricultural development accordingly. The Santa Rosalía region, for example, has the highest exposure V-index, offering a high ecosystem risk (Figure 5). In a relatively small area, Santa Rosalía has more water resources, which suggests a great advantage for wildlife to thrive. Biologically, it is the main centre of fauna species richness with a high density of endemic bioregions. We tentatively argue that Santa Rosalía is a priority site which will require a careful treat under the future growth of agricultural development. Considering many of these factors, it will require a more hands-on sustainability plan to reduce the impacts of unplanned agriculture. Being the smallest of the five municipalities in the OHP provides a managerial advantage, so this region should become an exemplary case of friendly and effective agrobiodiversity development. Other external pressures, such as its proximity to Puerto Gaitán by road and fluvial connectivity with other agro-hubs, suggest this area should be prioritised for further intervention by the national government and local actors.

On the other hand, Puerto López and Puerto Gaitán are more developed in agricultural growth than other regions in the OHP of Colombia. Although the V-index was not calculated for these two municipalities, we assume the exposure value could be even higher than the one in Santa Rosalía. Some rules should be established to develop a friendly agricultural expansion towards the east of the OHP using lessons learned from these two large municipalities. In this region, the government should establish a land care centre where a multisector partnership units and proposes actions that mitigate adverse impacts on the ecosystem’s health. In terms of biodiversity, the confluence of the upper Meta River and other tributaries such as Guatiquía, Yucao and Manacacías in Puerto López and the western boundaries of Puerto Gaitán makes this region vital for the conservation of unique elements of biodiversity. For instance, these regions have many secondary centres of endemism for fauna and flora (Figures 4B,D) that should be protected to reduce the risk of losing range-restricted species. Regional planning programmes in Puerto López and Puerto Gaitán municipalities should focus on landscape recovery and agronomical remediation; for example, implementing conservation zones based on soil carbon information (Hyman et al., 2022).

As expected, our V-index proved that a lower degree of spatial changes and association is found further east in the OHP suggesting a lower risk of environmental degradation. However, the spatial patterns of biodiversity highlight that La Primavera and Puerto Carreño were of high biological importance in terms of endemism associated with river ecosystems and outcrops. Remoteness and lack of road access in these municipalities maintain biodiversity less exposed to human impacts. These regions should be highly protected, and agricultural development should be even more carefully planned than any other region in the OHP. A solid effort to implement systems designed under a conservation agriculture and biodiversity vision is fundamental in these two agricultural frontiers.

A better scientific understanding of the effects of agricultural expansion on biodiversity is needed to shape policy and improve environmental management along this future agricultural frontier.

The distributional data for fauna and plants presented in the study are included in the article/supplementary material, further inquiries can be directed to the corresponding author.

All authors contributed to the study conception and design. Material preparation was performed by RD-G. Data analysis was performed by CG-O. Data collection of the fauna and flora species distribution was performed by GIZ under the supervision of CR-C. The first draft of the manuscript was written by CG-O and all authors commented on previous versions of the manuscript. All authors contributed to the article and approved the submitted version.