BIOTROPIA - The Southeast Asian Journal of Tropical Biology
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BIOCHEMICAL CHARACTERISTICS OF THIONIC FLUVISOL LINKED TO LAND USE TYPES IN SOUTHERN VIETNAM
No full textThionic Fluvisols soil in Southern Vietnam is like typical acid sulfate soil in the tropics and is severely polluted due to human activities. Salinity intrusion and industrial wastewater contamination are the main causes of environmental degradation in the soil ecosystem. This research aimed to determine a link between biochemical soil properties and land use types to provide suitable solutions for afforestation and soil restoration. Soil sampling was conducted in five different land use types at four soil layers (O, AB, Bj, and Cp). The five land use types were sugarcane crop; Melaleuca plantation; 2-year Acacia plantation; 5-year Acacia plantation; and control (grass-covered land). The results showed that soil in those five land use types was very acidic (pH ≤ 4) with poor nutrient conditions, with orthophosphate content ranging from 378–640 mg/kg, N-NH₄ from 586–999 mg/kg, and N-NO₃ from 830–1,112 mg/kg. Concentrations of toxic ions were very high, with large variation among land use types and soil depths: 1,799–12,403 mg SO₄²⁻/kg; 22–1,645 mg exchangeable Fe/kg; and 34–88 mg Al/kg soil. The lowest concentrations of exchangeable Fe²⁺ and SO₄²⁻ ions were found in sugarcane and Melaleuca plantations, respectively. Twenty-three sulfur-oxidizing bacteria and two iron-oxidizing bacteria were identified. All these bacteria were initially identified as Thiobacillus sp. Sugarcane and Melaleuca plantations exhibited the most diverse Thiobacillus species, which was linked to the reduction of exchangeable Fe²⁺ and SO₄²⁻ concentrations in these two land use types. This study indicated that Thiobacillus sp. could grow well in the Thionic Fluvisols. It is proposed that Melaleuca and sugarcane species could reduce iron and sulfur contents in Thionic Fluvisols in the tropics
ECOLOGICAL SERVICES OF AGROFORESTRY LANDSCAPES IN SELECTED WATERSHED AREAS IN THE PHILIPPINES AND INDONESIA
Get PDFThis article argues that the practice of agroforestry provides ecological contributions to smallholder farmers cultivating in watershed areas. Specifically, this farming system contributes to the carbon sequestration potential of woody perennials and the biodiversity conservation of other system components. This argument is based on research conducted in the Molawin-Dampalit Sub-Watershed, Mt. Makiling Forest Reserve in the Philippines, and the Way Betung Watershed in Indonesia. The research involved interview sessions with 106 and 261 smallholder farmers, and the assessment of 27 and 14 agroforestry plots for carbon stock assessment and biodiversity assessment, respectively. Results indicated that the total carbon found among the crop components was 52.32 MgC/ha in the Molawin-Dampalit Sub-Watershed and 244.26 MgC/ha in the Way Betung Watershed, suggesting a high carbon sequestration potential of woody perennials and understory crops in an agroforestry system. The farm lots cultivated by smallholder farmers were found to contribute to biodiversity conservation, having a moderate biodiversity index of 2.59 and 2.53, respectively. With these findings, the promotion of desired agroforestry systems in suitable portions of watershed areas should be intensified to contribute to ecological balance across the landscape. Agroforestry should always be an integral part of all initiatives toward ecological restoration, with cultivators or smallholder farmers as potential partners. The agroforestry system should consider all technical and socioeconomic factors to ensure diverse components and provide food security for smallholder farmers throughout the year
EFFECTS OF BLUE LIGHT AND PACLOBUTRAZOL ON SEED GERMINATION, VEGETATIVE GROWTH AND YIELD OF BLACK RICE (Oryza sativa L. ‘Cempo Ireng’)
Get PDFBlack rice (Oryza sativa L. “Cempo Ireng”) is one of the local rice varieties in Sleman Regency, Yogyakarta. Its black color is caused by a high anthocyanin content, which is an important source of antioxidants. The cultivation of black rice is still limited due to its tall phenotype, long vegetative stage, and lower productivity compared to white rice. Paclobutrazol is a growth retardant that causes dwarfing in several crop plants and reduces lodging. Blue light can improve plant quality. This research aimed to evaluate the effects of blue light and paclobutrazol on seed germination, vegetative growth, and yield of black rice. The results showed that the average seed germination and the α-amylase activity of seeds exposed to blue light were lower compared to those exposed to sunlight; however, paclobutrazol concentrations did not affect the seed germination percentage. The height of rice plants treated with paclobutrazol decreased in accordance with increasing paclobutrazol concentration. Chlorophyll content and tiller numbers increased with 12.5 ppm paclobutrazol treatment. Nitrate reductase activity was higher in rice seedlings subjected to blue light compared to sunlight. Iron (Fe) content in rice plants treated with 25 or 50 ppm paclobutrazol increased compared to the control. In conclusion, paclobutrazol application at 12.5 ppm effectively reduced plant height, and higher concentrations caused greater height reduction. Blue light treatment during black rice seed germination slightly reduced germination percentage and α-amylase activity. However, when combined with paclobutrazol application, blue light treatment increased chlorophyll content, tiller numbers, and Fe content in black rice grains
Eimeria SPECIES COMPOSITION AND FACTORS INFLUENCING OOCYST SHEDDING IN DAIRY FARM, BANDUNG, INDONESIA
Get PDFCoccidiosis is one of the most widespread parasitic diseases affecting cattle worldwide, caused by Eimeria spp. This study aimed to determine the composition of Eimeria species and the factors influencing Eimeria oocyst shedding in dairy farms. A cross-sectional study was conducted in dairy farms in South Bandung District from July 2014 to January 2015. Fecal samples were collected from 400 dairy cattle, consisting of 196 calves aged < 6 months, 37 cattle aged 6–12 months, and 167 cattle aged > 12 months. Samples were examined and quantified for Eimeria species composition and oocyst per gram (OPG) counts using the McMaster technique. A questionnaire was administered to dairy farmers to gather information on cattle health status and husbandry practices. The effects of sex, age, and pen flooring type on OPG values were analyzed using Mann–Whitney and Kruskal–Wallis tests, followed by Dunn’s multiple comparison test. Ten Eimeria species were identified in the infected cattle. Among them, Eimeria bovis showed the highest prevalence (42.5%), followed by Eimeria wyomingensis (39.1%), Eimeria bukidnonensis (32.4%), Eimeria pellita (26.3%), Eimeria auburnensis (19.6%), Eimeria zuernii (17.3%), Eimeria cylindrica (3.9%), Eimeria canadensis (3.9%), Eimeria brasiliensis (3.4%), and Eimeria alabamensis (1.1%). Oocyst shedding was significantly correlated (p < 0.05) with cattle sex, age, and pen flooring type, all of which influenced infection pressure. Younger calves aged < 6 months shed the highest numbers of Eimeria oocysts compared to older cattle. Several factors may contribute to the increased OPG in fecal samples; therefore, maintaining proper sanitation and implementing effective Eimeria control measures are essential for dairy cattle management in KPBS Pangalengan
PREDICTING THE IMPACT OF CLIMATE CHANGE ON THE DISTRIBUTION OF Flindersia pimenteliana F. Muell. IN INDONESIAN PAPUA AND PAPUA NEW GUINEA
No full textPopulation of Flindersia pimenteliana (Maple Silkwood) in Indonesian Papua and Papua New Guinea is severely fragmented and experiencing a continuing decline due to habitat destruction and illegal logging. This species is very susceptible to environmental changes and at greater risk of extinction due to its small and fragmented geographic ranges and low abundance. Using maximum entropy (MaxEnt) method, the present study predicted the impact of climate change on the distribution of the species across its native distribution area. Elevation and 19 bioclimatic variables commonly used in species distribution modeling were used as predictors. Â The prediction model of the current potential distribution identified a total area of 156,214 km2 in Indonesian Papua and Papua New Guinea (18% of total land area) as suitable habitat for F. pimenteliana. Elevation and precipitation of the wettest, coldest and warmest quarters contributed most to the model. Based on the average of HadGEM2-ES and MIROC-ESM models, potential distribution projections under RCP8.5 scenario suggested a habitat gain of 16% for 2050 and 8% for 2070 in the species distribution. Whereas under RCP4.5, an average habitat gain of 7% was predicted for both 2050 and 2070. The newly suitable habitats were predicted to be found mainly in Southern and Western Highland of Papua New Guinea. Protection of these areas from habitat destruction and land use change is needed to assist F. pimenteliana find the most suitable climate for its survival
EFFECT OF INVASIVE Ageratina adenophora ON SPECIES RICHNESS AND COMPOSITION OF SAPROTROPHIC AND PATHOGENIC SOIL FUNGI
No full textBelowground modification of soil microbial community by invasive plants is well evident. Similar instances of Ageratina adenophora invasion have been reported. This study was aimed to determine the effect of A. adenophora invasion on species richness, species or community composition and occurrence frequency of soil fungi. These parameters were analyzed using culture method on invaded and uninvaded soils. Species richness of soil fungi was lower in the A. adenophora-invaded soil compared to the uninvaded soil. The occurrence frequency of particular fungi was different for those two soil conditions. A. adenophora also altered soil fungi species composition in the invaded soil by replacing saprophytic fungi and accumulating pathogenic fungi. Thus, A. adenophora is associated to lower species richness of saprophytic soil fungi and high occurrence frequency of pathogenic soil fungi. This study concluded that the invasive A. adenophora modifies belowground soil fungi communities as one of the mechanisms involved in the successful invasion of A. adenophora
POLLINATOR DIVERSITY AND FORAGING DYNAMICS ON MONSOON CROP OF CUCURBITS IN A TRADITIONAL LANDSCAPE OF SOUTH INDIAN WEST COAST
Get PDFStudies on insect pollinator ecology and dynamics are rarely conducted in traditional Indian agricultural landscapes. Indiscriminate landscape modifications in rural areas and the increasing tendency toward crop monocultures may significantly affect pollinator habitats and effectiveness. This study aimed to observe insect pollinators, their visitation frequencies, and visitation timing on monsoon cucurbit crops such as Cucumis sativus L., C. pubescens Willd., Momordica charantia L., Trichosanthes anguina L., and Luffa acutangula (Roxb.) in a coastal village in Karnataka. The study also examined the significance of surrounding landscape elements in sustaining pollinator populations. Bees such as Apis dorsata, A. cerana, and Trigona sp. were the major visitors of all cucurbit crops, except snake gourd, which was primarily pollinated by lepidopterans. Insect species were found to partition floral resources with minimal overlap in their visitation times. Natural landscape elements—particularly the village forest and rocky savanna—provided important habitats for bees and lepidopterans. Prolifically blooming monsoon herbs on lateritic plateaus appeared to play a key role in supporting pollinator populations by providing nectar resources. These factors may contribute to the case study village being well known for its monsoon vegetables
HIGH OUTCROSSING RATE AND POLLEN DISPERSAL DISTANCE OF Diospyros celebica Bakh. (EBENACEAE), AN ENDEMIC TREE SPECIES IN SULAWESI ISLAND, INDONESIA
No full textDiosphyros celebica Bakh., also known as Sulawesi ebony, is an endemic to central and northern Sulawesi. Information about pollen dispersal patterns of D. celebica have not been previously investigated. This study was aimed to determine pollination type, percentage of selfing and outcrossing, as well as distance of pollen dispersal of D. celebica. This study was conducted at experimental forest of Universitas Hasanuddin, Maros District, South Sulawesi Province, Indonesia. One hundred and sixty six individuals of D. celebica consisted of adult trees and seedlings were analyzed in this study. Ninety four adult trees were selected to become parent trees. The trees were mapped with GPS coordinates . All samples were genotyped using four SSR markers loci. Parental analysis and determination of pollen dispersal patterns were carried out using Cervus 3.0.3. Results indicated that the evaluated markers were effective for assigning candidate of male parents to all evaluated seedlings. Donated pollens could come from male parents in any directions relative to female parent positions. Pollen dispersal pattern showed outcrossing pollination among different male parents (pollen donated trees). The results indicated that seeds were produced predominatly by outcrossing. Pollen dispersal reached up to 166 m. Pollen related processes were linked through female parents, pollinators availability and ecological environment. Simultaneous use of progeny genotyping, spatially explicit analysis of environmental variables and outcomes of plant–animal interactions, were the key elements for an expanded approach to gene flow analysis considering dispersal via pollen and seeds. Research on pollen dispersal of D. celebica should be carried out in other forest types, such as mixed forest and highland forest
PAYMENT FOR ENVIRONMENTAL SERVICES APPROACH TO REDUCE FLOOD IN CILIWUNG WATERSHED
Get PDFSpatial planning has already been stipulated in Ciliwung Watershed, but its implementation is often not in line with the rapid development activities. To fulfill space demand, agricultural and forest areas are converted into open or built-up areas because the economic appreciation of forest and agricultural land is lower than that of open or built-up areas. Payment for Environmental Services (PES) is a tool designed to overcome environmental mismanagement, which is beneficial for the lives of rural communities. PES should be considered in the formulation of spatial planning. This study was aimed to develop optimum land use pattern in reducing flood in Ciliwung Watershed, using PES approach. This study used a dynamic system approach, consisting of submodels for land use pattern change, runoff, value of farmland, upstream subsidy policy, population dynamics, and environmental services. The results showed that the PES policy should be able to maintain the existence of paddy fields and dryland farming areas and to reduce runoff if it is implemented in the form of guaranteed access to the market, and held in conjunction with efforts to prevent land conversion and to implement reforestation policies. The optimum land use pattern under this condition shall be reached in 2023, which consisted of 0.82% water bodies, 10.74% forest areas, 70.34% built-up areas, 8.16% dryland farming areas, 4.97% grassland areas, 2.39% paddy field areas, and 2.58% open areas. This land use pattern can reduce runoff in Ciliwung River from 972.04 to 850 cm, and this level is considered to be flood-free. Communities living in the upstream areas are the most effective managers of the watershed
RECOVERY OF RESIDUAL FOREST ECOSYSTEM AS AN IMPACT OF SELECTIVE LOGGING IN SOUTH PAPUA: AN ECOLOGICAL APPROACH
Get PDFPapua has been experiencing heavy logging activity in its forests for decades . However, only several studies focused on the effect of logging in the forest ecosystem. This research was aimed to analyze recovery processes of the forest ecosystem. The research was conducted in the logged tropical rainforest in South Papua using ecological approach which used tree communities as biotic and soil condition as abiotic indicators. Data were collected in the logging area of PT Tunas Timber Lestari located in the tropical rainforest of South Papua. There were five groups of forests used in this research i.e. unlogged, one year post selectively-logged, five years post selectively-logged, ten years post selectively-logged and fifteen years post selectively-logged forests. Thirty nested plots were laid on each forest group. Canonical Correspondence Analysis (CCA) was applied to analyze the understory and upperstory plant communities. Understory and upperstory plant communities formed different patterns due to logging. Plant communities in the ten and fifteen years post-selectively logged forests were not similar to those in the unlogged forest. Soil organic matter (SOM) content in the selectively logged forests was lower than that in the unlogged forest. These occurrences indicated that the selectively logged forests were still recovering and required more than fifteen years to be fully recovered