Plant Diversity and Status in the Northern Landscape of Mt. Malindang Range and Environs, Misamis Occidental, Philippines
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Distribution This forest was located in Barangay Peniel, Calamba, and Misamis Occidental. Land Use The estimated area planted with Acacia mangium was about 300 to 400 ha. The plantation forest was about five years old and initiated by the military officials and their personnel as part of their civic action program. The initiative had since been transferred to barangay officials. Another major plantation crop was Cocos nucifera, a local source of cooking oil. Agroecosystems Diagnostic species The agroecosystem was typified by seeded or planted vegetables like Brassica oleracea, Sechium edule and Allium fistulosum (cabbage, chayote and green onions), and cereals like Oryza sativa and Zea mays (rice and corn). For agroforestry, there were Cocos nucifera (coconut) and Lansium domesticum (lanzones). Grass-dominated fallowed areas (Cyathea spp. And Paspalum conjugatum) were part of the characteristics of the agroecosystem. Structure Crops like vegetables, cereals and agroforestry species dominated the agro/ agricultural ecosystems. These agricultural crops were also interspersed by herbs (grasses/weeds/ferns) and few trees/saplings: Melicope confusa, Bischofia javanica, Lithocarpus sp., and shrubs: Melastoma malabathricum Saurauia elegans, (endemic), and S. involucrate (endemic) which were forest remnant species. The high number of tree saplings and fallen logs in these areas were evidence that farmers of Barangay Lake Duminagat recently burned the natural forest. Floristic diversity A total of 73 cultivated crop species were: 24 species and 74 varieties were vegetable crops, 23 were fruit crops, 7 were plantation crops, 5 were cereal and grains, 8 were ornamental, and 6 species were industrial plantation crops. More number of weed species were found at higher elevations (>1,000 m asl) than in lower elevations, possibly due to cooler environment and farming practices of multicropping with annual crops. At lower elevations (<1,000 m asl), the practices of intensive cultivation resulted to lesser weed diversity. Here agroforestry farming systems were also found. Ecology The agroecosystems were found at an altitude ranging from 150 to 1,400 m asl. At high altitudes, there were lower temperatures (20.62oC to 22.75oC) and higher precipitation (8.75 cm/day in Mansawan, Gandawan, Lake Duminagat, Sebucal and Mialen). Climate was warmer at low altitudes (temperature 26.93oC), with less precipitation (4.09 cm/day in Toliyok, Bunga Peniel and Mamalad). The slopes ranged from 5 to 30 degrees. The parent soil material was predominantly sandy loam; the soil pH was acidic (averaging 5). Distribution The agroecosystems was located in all barangays covered by the research sites of Mt. Malindang Range Natural Park, Misamis Occidental. Land Use Barangays Mansawan, Gandawan, and Lake Duminagat were suitable places to grow vegetables and rootcrops. Cabbage was the major cash crop, but problems on pest and diseases reduced the yield. Corn was a primary cereal crop raised by the farmers in all barangays, while rice was favorably grown in both upland and lowland areas in Oroquita City, Lopez Jaena, and Calamba. Sebucal, being the innermost and remote barangay of Oroquita City, Focused on growing cereals (upland rice, corn), root crops, and fruit crops like cassava, kanaka, and banana mainly for subsistence. The barangay Mialen, Toliyok and Bunga in Oroquita City were more advantageous having favorable soils and climate for growing fruits and cash crops like lanzones, coconut, marang, durian, rambutan, and bananas were grown in the barangays. Some vegetables were also grows so well under the farmers who earned money by working as laborers, and by fishing and hunting. Species Richness/Floristic Diversity Inventory of the plant species in all research sites (Sampling plots and transect walk) revealed a total of 1,284 species, 472 genera and 187 families. Among the group of plants 873 species were classified as angiosperms, 20 as gymnosperms, 280 as pteridophytes, 85 as bryophytes and 26 species as lichens (Table 8 and Appendix Table 4). The percentage of angiosperms, gymnosperms and pteridophytes was comparatively higher than the percentage reported by Tabaranza et al. (2001) and Arances, et al. (2004). For pteridophytes alone, the number of species recorded represented about 44% of the 632 species found in Mindanao (Amoroso 2000). On the other hand, Zamora and Co (1986) reported that 33 species of gymnosperms in the Philippines and 20 species (or 60%) were found in Mt. Malindang. However, at the time this study was conducted, many species still remained unidentified. The barangay with the highest species richness was observed in Lake Duminagat and Sebucal (Table 9). The high species richness had been attributed to the presence of three mountains with two forest types (mossy and montane) in Lake Duminagat, namely, Mt. Ulohan sa Dapitan, Mt. Ginlajan and Mt. Tandayan (North Peak), and two forest types in Sebucal (submotane dipterocarp and almaciga forests). Because of diverse habitats coupled with high altitude, lower temperature and high rainfall, high diversity of plant species was observed in these two barangays . As shown in Table 17, tree species richness decreased with increasing altitude (1,400 to 2,185 m asl). This fact supports the contention of various of ecologists that the number of species at higher altitudes is lower as a response to increasing environmental stresses like wind pressure, steep slopes, thin soil substrates, etc. (Perez 2004). However, an opposite trend was observed in the group of pteridophytes since an increasing number of ferns species was recorded with increasing altitude. This trend was expected since ferns prefer cooler temperature, and moist and shaded habitat. As for vegetation, the montane and mossy forests had the highest species richness (263 and 256 species, respectively), followed by submontane and mixed dipterocarp forests with 219 and 181 species, respectively. Low species richness was noted in mixed lowland dipterocarp and plantation forests (97 and 61 species, respectively. The high species richness in the aforementioned forest types was partly due to the more diverse habitats and more sampling areas (12-21 plots/site). On the other hand, 154 species were found in the almaciga forest, which occupied only a small area (only six plots) compared to the other forest types. It had the highest species richness at 32 species per plot; which translates into extremely high diversity. This was followed by mossy, montane and submontane dipterocarp forests (30, 29 and 28 species/plot respectively) with very high plant diversity .The high species richness or diversity values in these areas may be attributed to the presence of intact forests. Trees and shrubs associated with the agroecosystems in the barangays Don Victoriano were also recorded. A total of 38 species in 26 families were documented (Appendix Table 3). Lake Duminagat had the highest number of remnant tree and shrub species (31 species) in the cultivated areas planted with vegetable crops (compared with Mansawan which had 90 remnant species and Gandawan which had remnant species). The higher number forest remnant species (trees/saplings) and fallen logs was a strong indication that farmers of Barangay Lake Duminagat recently burned the natural forest. The barangay was surrounded by vast areas of natural forest that promoted diversity of trees and shrubs in the agroecosystem. If Kaingineros can be stopped from expanding cultivation and the area can be followed for a longer period, secondary forest development is possible. The influx of forest dwellers and increasing population led to a further reduction of the natural forest, as people try to find ways to survive by using the forest resources as their livelihood. Species Similarity Index of Forest Vegetation Types Similarity indices the decreasing values (29.55%), to submontane dipterocarp forests (8.79%), to almaciga forests (5.61%), to mixed dipterocarp forests (4.62%), to lowland dipterocarp forests (3.21%), to lowland mixed dipterocarp forests (3.03%), and to plantation forests (2.07%)(Table 13). Similar trends existed in other vegetation types. Species similarity among vegetation types showed that plant species in mossy forests had more similarity to montane forests had similarity to montane forests (29.55%) and least to other vegetation types (Table 13) The same is true for lowland dipterocarp forests to lowland mixed dipterocarp forests (30.60%); submontane dipterocarp forests (26.12%); almaciga to submontane dipterocarp forests (25.32%); and mixed dipterocarp to plantation forests (25.49%). The degree of similarity among vegetation types was not significant except between the plantation forests to lowland mixed dipterocarp forests . The vegetation types also represented the various elevation gradients across the landscape. Observably, these similarity values are low, indicating wide disparity among plant species contained in the various forest vegetation types. These findings showed dissimilarity among plant species across the landscape due to the influence of climate altitude,, aspect, soil, use of the forest and other factors. Species Similarity Index of Agricultural Crops in the Agroecosystem The similarity and degree of correlation of the plant species and varieties found across the Malindang landscape showed a higher degree of association in barangays found at higher elevations such as Lake Duminagat, Mansawan and Gandawan. The similarity index values ranged from 74.82% to 80.85% (Table 15). The high correlation coefficient that ranged from 0.895 to 0.9634 (Table 16) supported the planted. The above places have been classified as vegetable growing communities. Barangays at lower elevations practicing agroforestry were dominated by coconut intercropped with other fruits such as Lansium domesticum (lanzones), and Durio zibethinus (durian). Similarity values of the associated crops among the barangays ranged from 62.06% to 94.26%). However, Barangay Mamalad showed lower correlation values when compared with other barangays except with Sebucal. With respect to the general landscape of Mt. Malindang, Oryza sativa (rice), Ipomoea batatas (camote), and Colocasia esculenta (gabi) were dominantly cultivated either as sole or crop or as a component crop with chi square values of 36.0909, 23.5849, and 18.5714 respectively, based on aggregated analysis. They also served as staple food and cash crops of the Subanon and other tribes living across the Malindang Range. Assessment of Status An assessment of the status of the different plant species was carried out to establish a foundation for their protection, conservation and monitoring. Assessment of the status of each species revealed 56 threatened species both locally and nationally, 138 endemic species, and 289 species of economic value. Of the 56 threatened species, 10 were critically endangered, 9 endangered, 14 vulnerable and 21 were locally threatened. Twenty-nine species were endemic to the Philippines and 20 species threatened for extinction in the wild. Seven endangered species were seen only on the transect walk and not found inside the sampling plots. These were Dawsonia superba Bryum russulum, Alocasia sanderiana, A. zebrine, Lycopodium magnusianum, Dracontomelon dao, and Salacca clemensina; while only five endangered species were found inside the plots, Namely, Tmesipteris lanceolata, Dillenia philippinensis, Calamus merrillii, Podocarpus lophatus, and Agathis philippinensis. Furthermore, Oleandra nitida was found in the transect walk as inside the sampling plots. This species was reported by Zamora and Co (1986) as endemic and may become extinct if no conservation measures were adopted. Other species of dipterocarps reported as critically endangered were Anisoptera thurifera, Diptorocarpus grandiflorus, D. validus, Hopea acuminate, Shorea contorta, S. palosapis, and S. polysperma (DENR 2000). Among the plant groups, trees and gymnosperms obtained the highest percentages of endemism with 41% and 27% respectively, while angiosperms showed 24% of endemism and pteridophytes, 11%. Of the total 59 endemic pteridophyte species found in Mindanao, 28 species (47%) of endemic pteridophytes were from Mt. Malindang (Amoroso 2000). One species was site endemic (Medinilla malindangesis), while 10 species were Mindanao island endemics. The latter included Saurauia fasciculiflora and Saurauia glabrifolia. Fourteen plant species were widespread Philippine endemics. Luzon endemics like Begonia cumingii, Vaccinium jagorii, and Saurauia fasciculiflora had been recently reported in Mindanao. Some of these endemic species were also observed in the two 1- ha plots in the first generation research of Arances et al. (2004). Since some of the endemic species had been already reported as threatened, high priority should be given to the protection of these species. One of the Mindanao endemic species in Mt. Malindang was Salacca clemensiana, previously found only in certain parts of Mindanao such as Lanao, Zamboanga and Davao (de Guzman et al. 1986. The recent discovery of S. clemensiana in the Mt. Malindang Range represented a new distribution record. Previous assessment of its conservation status classified it as rare but the study showed that this species was quite common in the headwater portion and along the banks of Layawan River. Gruezo and Amoroso (2004) described the taxonomy, ecology, phenology, population size and reproductive behavior of S. clemensiana and further indicated that this was a Mindanao endemic palm. However, S. clemensiana is reported to occur also in Borneo (Co, Personal communication 2005). It has high commercial, landscape and ornamental value. The fresh mature leaves were being used by the native people as thatch roofing for small houses. The ripe fruits were eaten by the residents and by certain wildlife such as palm civet cat, macaque and cloud rats. Two hundred fifty species in the park had economic importance as food, medicine, ornament, building material, handicraft and forage (Timada 2003; Arances et al. 2004). These resources could provide sustainable livelihood to the local people if properly managed and utilized. These sustainable products, which were characterized as NNTP’s, were locally threatened due to overutilization and conversion of the forestland into agricultural land human settlements. Threatened Plant Resources The almaciga, submontane dipterocarp and lowland dipterocarp forests contained the highest number of threatened species with 6, 6 and 4 species per plot, respectively Other forest types had lower number of threatened species (1-2 species per plot). The high number of threatened species in the three forest types may be correlated with the higher diversity and the occurrence of dipterocarps species and species valued as timber for housing materials and firewood. In addition, these forests types were located in accessible areas, i.e., near human settlements and therefore more prone to disturbance and resource utilization. The 56 locally and nationally threatened species were found in nine particular barangays encompassed by the Mt. Malindang Range Natural Park (Table 18). Barangay Sebucal had the highest number of threatened species (31), followed by Lake Duminagat (29), while Barangay Gandawan had the lowest number (11). The high number of threatened species in Sebucal came from the intact almaciga forest and submontane dipterocarp forests; while in Lake Duminagat, from the relatively virgin montane and mossy forests. In Barangay Gandawan, only small remnants of intact forests could be encountered, hence the low number of species. The presence of the nearby settlements also explained the higher number of threatened species in Barangay Sebucal and Lake Duminagat. Overutilization of he forest resources and conversion of the forest into agricultural lands had endangered some of the plant species. The use of the wood of Lithocarpus spp., Syzygium spp., and Viburnum odoratissimum for firewood caused the depletion of the population of the tree species; they were recently considered as locally threatened. The data gathered by the SEC studies team indicated that the average extraction rate per week per household was roughly 0.192 m3 or 2.20 trees (15-20 DBH and 5m high). This extraction rate, coupled with the increase of the local population, and lack of reforestation, may lead to the conclusion that these tree species, presently being used for firewood, may be extinct in the near future. Tree planting of these species around farms had been encouraged to avert depletion of the population. These conclusions are underpinned by the stand table per hectare of the threatened species . Almaciga trees (Agathis philippinensis) are protected by the DENR and almaciga resin tapping is permitted only under license. However, local communities in Sebucal and Lake Duminagat illegally tapped almaciga resin for household use as illuminant. In samara, the San Jose Timber Corporation processed the resins into local varnish and paints for furniture and handicraft industries (FPRDI 2000). The people in the community had crude and old- fashioned extraction practices, with no restrictions to diameters of trees to tap and used horizontal cutting without definite thickness prescription. Unless such methods of resin extraction are corrected, the almaciga trees in Sebucal can become extremely threatened. Rattan (Calamus spp.) or “Climbing palms” were found abundantly in Barangay Sebucal, and fairly in Peniel, Lopez Jaena and Toliyok in Oroquita City. It was used for making basket strips and tying materials. In Sebucal, rattan was collected from the nearby almaciga forest and dipterocarp forest by pulling down the whole cane, thereby killing the plants in the process. Since there was no local experience with asexual reproduction, the high frequency of observed wildings was a result solely of high seed germination. However, since it takes about 15 to 20 years for rattan to mature enough to be harvested (Palaypayon and Cadiz 1988), local people resorted to collecting the young and immature canes, which contributed to the fast dwindling of rattan in Peniel, Toliyok and other places in the park. Sustainable rattan industry in Sebucal and other parts of the natural park may only be achieved through establishment of rattan plantations. Indigenous Knowledge System (IKS) on Conservation Indigenous agroforestry practices were land use forms, which were products of experiences, intelligent analysis of problems, and their solutions, refined through time (Cardenas and Oscar 2003). In the three barangays Don Victoriano (Mansawan, Gandawan and Lake Duminagat), in four barangays Oroquita City (Sebucal, Mialen, Toliyok, and Bunga) as well as in Peniel, Lopez Jaena, and Mamalad, Calamba, Misamis Occidental, the indigenous agroforestry practices of the Subanons and other tribal groups had most likely evolved as a strategy to cope with the existing biophysical and socioeconomic conditions in the upland ecosystem. Key informants said that whenever a new crop was introduced and the locals found it productive, many others adopted it. This implied open mindedness of the farmers and their eagerness to embrace technological to embrace technological improvement. Farmers in the different barangays were found to trust their own indigenous knowledge and beliefs. Farmers in settlements at higher altitudes in Mt. Malindang used the splash and the burn farming method (Kaingin) to raise crops. They cleared the areas to be farmed by cutting down the trees and burning the remains. This practice was done in logged-over or fallowed areas at higher elevations, like in Don Victoriano and Lopez Jaena, Misamis Occidental. It was observed that the most of the kaingins were done in sloping areas which were very prone to surface run-off and erosion. Subanon farmers in the higher zones preferred to cultivate in the rolling areas because they found it easier to work standing across the slope than on flat land where they had to stoop or seat while working. This was aggravated by the clean monoculture practice of the most farmers: planting cabbage and onions on newly opened sites. As soil fertility declined, other crops, such as sweet potato and gabi, were usually promoted. This practice of Subanon farmers was similar to the practices of other ethnic groups in the Philippines (Denevan and Padock 1988; Cardenas and Oscar 2003). The Subanon farmers, however, observed a longer fallow period (3-4 years) to restore the soil fertility. Some farmers, made aware of the problematic situation of their farms, adopted innovations to improve production. Some of their innovations were: the application of fertilizers to their cash crops, such as cabbage and green onions; construction of diversion ditches or dikes; construction of rock walls or balabag system using decomposing logs; retention of uprooted weeds; and multiple cropping with sweet potato planted at the lower portion to trap eroded soil. However, in areas below 1,000 m asl, farmers resorted to the planting of permanent crops such as coconut and their trees resulting in an agroforestry farming system. Coconut farmers also practiced girdling of the coconut stem on the first one meter above the ground to remove the dead roots. They believed that by doing so, the fruiting of the coconut can be induced. This belief corresponded with scientific findings that tapping or creating bark injuries would induce the release of the stress hormone ethylene. Ethylene is developed within the plant system and can induce maturity and fruiting when it enters the plant stomata. They also wrapped coconut stem with galvanized iron and plastic floor mats to restrict the rats from climbing the trees and eating young coconut fruits. Farmers believed also that the opening the orchid ting-ulan indicated the coming of rain. They also believed that the following and fruiting of Lithocarpus spp. Signaled the right time to hunt for wild pigs. But the most significant practice of the Subanon farmers was the conduct of rituals to ask permission form the mountain spirits to use the lands, for they believed that the spirits own the lands. It was found out, however, that Christianized Subanons no longer followed such practices. Some of the documented Subanon farmers’ IKS on conservation and protection of Mt. Malindang were scientific in nature. They were also found to contribute to the increase of productivity in the agroecosystem. The Subanon’s balabag system, for example, promoted soil conservation and minimized soil erosion. Their fertilization through both organic and inorganic fertilizers had been proven scientifically to manage soil fertility. It was observed that there were more indigenous farming practices in the barangays located in higher elevation than those in the lower elevation. Perhaps, differences in exposure to modern farming practices can account for this. The barangays in the lower elevation had more exposure and access to modern farming technologies coming from the lowlands. Development of Biodiversity Monitoring and Conservation Instrument The community monitoring teams used an instrument developed by the Central Mindanao University and Bukidnon Resource Foundation to monitor, evaluate and conserve biodiversity. The instrument was used during the training conducted in December 2004where 54 participants from Mansawan, New Liboron, Gandawan and Lake Duminagat attended. As suggested by the participants, two community monitoring teams (CMT) namely, Mansawan- New Liboron CMT and Gandawan-lake Duminagat CMT, were organized. The Barangay Captain headed each community team and the Bantay Lasang (Forest Guards) were the members. During the training, the researchers from the study and from the Bukidnon Resource Foundation acted as resource persons. The selection and installation of the BIOME sites were demonstrated. The participants decided to install the BIOME sites in the two 1-ha plots in palo 6, Barangay Mansawan and in Mt. Ginlajan, Barangay Lake Duminagat. To make biodiversity monitoring an evaluation sustainable even beyond BRP, the CMT’s were empowered by teaching them the tools of biodiversity monitoring. These were: transect walk (TW) , photo documentation (PD), field diary (FD) and focus group discussions (FGD). Hands–on activities followed the lecture/demo and they were asked to gather initial data from the 1-ha plot. The CMT’s were then taught how to organize, analyze and interpret the data collected from the field. Ultimately, they were given tips on how to present the results of the BIOME activities. On the last day, the participants became involved in action planning and preparation of the proposals to continue the BIOME activities and nursery project even after BPR ends. The proposals were submitted to the park superintendent for discussion during the meeting of the Projected Area Management Board (PAMB) and officials of the local government units (LGUs). The TEMP flora researchers were designated to continue the activities of the CMTs so that trends in species biodiversity (Whether increasing or decreasing) could be determined and changes in the landscape recorded. The results of the BIOME activities can be useful for the policy and ordinance formulation of the PAMB or other local government units in the conservation of remaining biodiversity in Mt. Malindang Natural Park. The BIOME was not only expected to build the capabilities of the CMT and communities in determining changes in the biological and economic resources that they mange, but to also identify and formulate timely and appropriate conservation management interventions based on the gathered data. Information, education and communication (IEC) materials, such as flyers of threatened and endemic plant species were prepared to disseminate information and to enhance awareness regarding the biodiversity status of the park. |