Evaluating the status of forest understory plants on high demand in an “open access” setting for restoration and community engagement

Abstract

Knowledge of how human harvest impacts plants on high demand for non-timber forest products is essential for targeted conservation. Herbs and shrubs are some of the main sources of such products. However, documentation of human impact on forest flora usually focuses trees. We assessed the status of three forest understory shrubs on high demand for various non-timber forest product uses around Mabira Central Forest Reserve, Uganda. Acalypha neptunica is popular for commercial meat roasting and vending. Citropsis articulata and Calamus deerratus are collected for medicine and furniture making respectively. Harvest impact on A. neptunica and C. articulata was assessed using transects with human trails as a reference in 12 of the 66 management compartments of the reserve. C. deerratus , was assessed through a reserve-wide search. A. neptunica and C. articulata increased significantly with distance from human trails (Jonckheere-Terpstra Tests: A. neptunica , p = 0.022; C. articulata , p < 0.0001) suggesting occurence of human harvest impact on density. All species showed significant decrease uphill from the valley bottoms (Jonckheere-Terpstra Tests: C. articulata , p < 0.0001; C. deerratus , p < 0.0001; and A. neptunica , p = 0.004) indicating intrinsic vulnerability due to habitat specificity. Interspecies comparisons of density showed A. neptunica to be much more abundant than C. articulata . C. deerratus was localized to patches along some, but not all valley bottoms. A. neptunica exhibited a high level of post-harvest re-sprouting and appeared favored by moderate forest disturbance. C. articulata also showed frequent re-sprouting. These results complement prevailing understanding that conservation actions are urgently needed for C. articulata and C. deerratus . The results also show that further long-term investigation is required to fully understand the plants’ response to harvesting and this needs to be facilitated by enforcing the existing strict nature reserve status of the core of the forest.

Occurrence of Citropsis articulata in Tropical Forests in Uganda: Implication for Ex Situ Conservation

“…e forest reserve is partitioned into three management zones, i.e., strict nature reserve (in which no activities are permitted except scientific research), buffer (in which recreational activities and collection of nontimber forest products are permitted), and production (managed for sustainable supply of timber forest products) [8,21]. e forest is also masked with village enclaves that are widely distributed within the forest area (Figure 2).…”

“…Variation However, these were more evident in Budongo and Mabira Central Forest Reserves. Occurrence of these illegal activities in the forest reserves can lead to incidental cutting of C. articulata by users seeking resources from the forest [8].…”

“…Despite the measures put in place by NFA to protect central forest reserves as stipulated in the forestry policy, prohibited activities such as illegal logging, charcoal production, and illicit harvest of nontimber forest products (NFTPs) still persist in most central forest reserves. is in part is attributable to the management weaknesses such as weak law enforcement resulting from limited staffing [6,8]. e predicament is further compounded by the location of some forests near metropolitan areas in addition to having settlement enclaves within the forest reserve boundaries; case in point is Mabira Central Forest Reserve.…”

“…Besides, Okeowo [11] noted that C. articulata is disappearing in Mabira Central Forest Reserve at an alarming rate. is was attributed to overexploitation and unsustainable methods of harvesting, owing to increased demand and commercial value for its roots [8]. Additionally, factors such as environmental degradation and climate change may further increase the vulnerability of this plant species.…”

Restoration of Citropsis articulata, a Species at Risk from Medicinal Overharvesting in a Ugandan Rainforest Reserve

“…e reported reproductive effects of C. articulata have drawn a raft of studies on its medicinal applications [3][4][5][6][7][8]. However, the threat of overharvest has drawn less attention [9,10] and possible methods of in situ restoration have not yet been investigated. e objective of this study was to assess the potential for use of seeds in enhancement of the wild populations.…”