Acacia Crassicarpa Research Articles

The role of Acacia crassicarpa plantation forest in Peatland in reducing CO2 emissions

Abstract Acacia crassicarpa is a fast-growing plant on peatlands that is capable of binding atmospheric CO2 and storing it in carbon. The study aims to calculate carbon stocks in Acacia crassicarpa plantations and their potential to absorb atmospheric CO2. The research was performed in an industrial plantation forest in Siak Regency, Riau Province. The observation plots employed stratified random sampling by measuring the height and diameter of Acacia crassicarpa aged 12, 24, 36 and 42 months, as well as the biomass of undergrowth and litter. Stored carbon was estimated by calculating tree biomass through the approach of specific gravity and trees volume, while for understory plants and litter was based on their dry weight. The results exhibited that Acacia crassicarpa aged 12, 24, 36 and 42 months had carbon stocks of 4.14 tons/ha, 18.55 tons/ha, 43.82 tons/ha and 69.39 tons/ha. The ability of the stand to absorb CO2 in the atmosphere is 15.23 tons/ha, 68.08 tons/ha, 160.81 tons/ha, and 254.67 tons/ha. The potential carbon stored in the understory stands at 0.64 tons/ha, 0.79 tons/ha, 0.85 tons/ha, and 0.86 tons/ha. The carbon stored in litter is 0.80 tons/ha, 1.27 tons/ha, 1.49 tons/ha, and 1.5 tons/ha.

Effects of Harvest Time and Acacia crassicarpa Age on the Physicochemical Characteristics of Apis mellifera L. Honey in Tropical Indonesian Forests

The comprehensive understanding of the physicochemical profile of monofloral honey derived from Acacia crassicarpa, specifically in the Indonesian tropical forest ecosystem, has not been fully explored. The physicochemical characteristics of honey significantly influence its quality and consumer acceptance. Harvest time and the age of Acacia plants, which are suspected to affect honey’s physicochemical properties, are this study’s focal points. Our objective is to analyze the impact of harvest time and Acacia age on the physicochemical characteristics of honey. Using a complete randomized block design, treatments were administered at 14, 21, and 30 days of harvest within three Acacia age groups: 3, 8, and 18 months. The honey composition was assessed following the Indonesian National Standard 8664:2018 procedure. The statistical analysis determined the optimal harvest period for honey by assessing its physicochemical properties and comparing them to the Indonesian National Standard 8664:2018 procedure (SNI 8664:2018 standards). One-way analysis of variance evaluated the effects of harvest time and plant age on composition, followed by a least significant difference tests to identify significant differences between harvest times. Results indicate a significant influence of harvest time and Acacia age on all honey composition variables, including diastase enzyme activity, hydroxymethylfurfural content, moisture level, sugar content, and acidity (P<0.01). Our findings suggest optimal honey harvest at 30 days, aligning with the 8th and 18th months of A. crassicarpa. Most variables met SNI 8664:2018 standards, except acidity levels. Further investigation is needed to discern the causes of acidity in Apis mellifera honey from Indonesian peat swamp forests.

QUALITY OF ACACIA CARPA HONEY AS A POTENTIAL INGREDIENT FOR CHILDREN’S MOUTHWASH

Dental caries is a dental disease that is most often experienced by people. One way to prevent caries is to gargle with mouthwash. Honey has become one of the natural ingredients that can be used as a mouthwash drug content. Jambi Province is one of the provinces that makes honey a non-timber forest product (NTFP). It is necessary to carry out physical and chemical tests on honey to determine the quality of honey as a basic ingredient for mouthwash. The honey samples examined were honey harvested from honey farms in Danau Lamo, Maro Sebo District, Muaro Jambi Regency, Jambi Province. This type of honey is Acacia Carpa (Acacia crassicarpa) honey from Apis mellifera honey bee farming. The honey tested consisted of honey that had undergone processing and raw honey. The honey testing carried out consists of organoleptic tests, physical tests and chemical tests. Testing was carried out at the Jambi Province Department of Industry and Trade. The inspection results show test results that comply with SNI 8664-2018 such as water content, water-insoluble solids, ash content, HMF, and diastase enzyme levels. The pH of honey is 3.7 and is in accordance with the honey pH standard. Substances that do not comply with SNI 8664-2018 are reducing sugar levels and sucrose levels. Honey with high sucrose content can still be used as a basic ingredient for mouthwash, but it must be based on the results of clinical trials to ensure its effectiveness and safety

GARLING WITH A SOLUTION OF ACACIA CARPA HONEY SOLUTION OF 10% CONCENTRATION ON THE DEGREE OF SALIVA ACIDITY AND THE TOTAL PLATE COUNT (TPC) OF THE NORMAL FLORA OF THE ORAL CAVITY IN CHILDREN

Saliva functions as a buffer that can prevent a decrease in pH or an increase in mouth acidity. Alcohol-free mouthwash containing herbs using honey solution which is made from natural ingredients and is safe for children can be used as an appropriate preventive measure to maintain oral hygiene. The normal flora of the oral cavity consists of microorganisms including bacteria, fungi, mycoplasma, protozoa and possibly viruses. The aim of the research was to analyze the effect of gargling with a 10% concentration of Acacia Carpa (Acacia Crassicarpa) honey solution on the degree of saliva acidity and Total Plate Count (TPC) of normal oral flora and Gram bacteria in children aged 8-9 years. Method: True experimental research type, with a group pre-test post-test with control group design. The sampling technique was carried out by simple random sampling of 30 children. The degree of acidity of saliva is measured using litmus paper, bacterial colonies are incubated on Nutrient Agar media for 24 hours and counted. Test the normality of the data using the one sample Kolmogorov-Smirnov test. Data were analyzed using the Paired T-test if it was normally distributed and the Kruskal Wallis test if it was not normally distributed. Results: The 10% concentration honey gargle group resulted in the average degree of acidity before, namely 7.00, after 6.98, then the average Total Plate Count (TPC) result for normal oral flora, namely before, was 100.47 CFU/ml, whereas after, it was 69.67. CFU/ml. Paired T-Test test results for the 10% honey gargle group Sig. 0.003 (< 0.05), so there is a significant difference between the Total Plate Count (TPC) before and after gargling honey with a concentration of 10%. Conclusion: There is an effect of gargling honey with a concentration of 10% on Total Plate Count of normal oral flora

Capability lignin from Acacia crassicarpa black liquor as an environmentally benign antibacterial agent to produce antibacterial and hydrophobic textiles

Recently, the growing health awareness of society on the utilization of fabrics has led to an increasing demand for natural-based antibacterial textiles. Lignin, a generous polyphenol compound in nature, is capable of preventing bacterial growth; in particular, it dwells bacteria closely together on human skin, such as Staphylococcus epidermidis, Bacillus subtilis, Propionibacterium acnes, and Staphylococcus aureus. However, the antibacterial properties of lignin are limited by factors such as the lignin concentration, source, and type of bacteria. This study aimed to evaluate the potency of lignin as an antibacterial agent for textiles. Moreover, the thermal properties and wettability of the textile after lignin coating were also investigated. This study showed that lignin isolation methods significantly contributed to the inhibition of bacterial growth in the clear zone diameter. In addition, the lignin structure, lignin concentration, and type of bacteria had notably different antibacterial effects. SEM images showed that lignin was successfully coated on the fiber, and the antibacterial textile was successfully fabricated with clear zones in the range of 0.1–0.5 cm against four different bacteria. Lignin did not significantly improve the thermal stability of the textile, as proven by the TGA results. After the HDTMS coating by dispersion method, the wettability of the lignin-textile improved to that of the hydrophobic material, with a contact angle greater than 119.05° with excellent antibacterial properties (clear zone of 0.1–0.43 cm).

Nutrient Resorption in Young Stands of Three Native Tree Species to Support Restoration of Degraded Tropical Peatland in Indonesia

Nutrient resorption (NR) is a critical ecological process in forest ecosystems. However, there is a lack of knowledge about this process in the peatlands of Indonesia, and this may be seen as a research gap. In the present study, NR in young trees of three native species (Macaranga pruinosa, Cratoxylum arborescens, and Macaranga gigantea) and one exotic species (Acacia crassicarpa) in a drained tropical peatland was investigated. This study was conducted at an experimental plot in Pelalawan-Riau, Indonesia. Nutrient resorption efficiency (RE) and proficiency (RP) were calculated and correlated with soil properties, foliar nutrients, and growth variables. Our results revealed that M. pruinosa exhibited an RE value for phosphorus (PRE) that was 64% higher than that for the second-ranked native species but still significantly (84%) lower than that for A. crassicarpa. RE values for nitrogen (NRE) and potassium (KRE) did not differ significantly among species, ranging from 39 to 42% and 41 to 56%, respectively, for native species, with figures of 45% and 66%, respectively, for A. crassicarpa. Finally, PRE exhibited strong and significant correlations with PRP and tree growth, a finding that indicated that the uptake and conservation of P nutrients are essential for the fitness of the three native species. Overall, the results of the present study may be seen as beneficial for species selection and the management of nutrients by those engaged in restoration of tropical peatland forests.

Physiological Responses and Tolerance of Three Acacia Species to Cadmium Stress During Germination and Early Seedling Growth

Soil contamination with cadmium (Cd) is a serious threat to ecosystems. Phytoremediation is a cost-effective green technology that can be used to clean up Cd pollution, and Acacia species are potential phytoremediation agents due to their fast growth, significant biomass, and tolerance to environmental stresses. Most studies of Cd stress on Acacia focused on later vegetative stages and the tolerances during germination and early seedling are elusive. This study aimed to assess the tolerance of Acacia mangium, Acacia crassicarpa, and Acacia auriculiformis to Cd stress during germination and early seedling growth. In response to 250 μM Cd treatment, A. auriculiformis germination was slightly increased compared to the control. Leaf organ formation remained largely unaffected by Cd stress, except for the true leaf number in A. mangium, which was significantly higher in response to 125 µM Cd than those to 250 µM Cd treatment and control at 8 and 10 weeks after treatment. The onset of phyllode development transition from true leaf was significantly delayed in A. mangium compared with the other two Acacia, irrespective of the presence of Cd. There were no significant differences in leaf gas exchange parameters (photosynthesis, stomatal conductance, and transpiration), leaf-level water use efficiency, or leaf chlorophyll content between Cd-treated and control plants, suggesting that the three Acacia species are tolerant to Cd at both germination and early seedling phases. Cd accumulation during the experiment was very low in A. mangium seedlings (2.8 mg kg-1 upon 250 µM Cd) and insignificant in A. crassicarpa and A. auriculiformis, indicating non-hyperaccumulation or Cd exclusion at the seedling stage.

Acidic soil-tolerant tree species identification

Previously, surface soil acidity was amended by the application of lime, gypsum, and acidic soil-tolerant crop species. However, their effectiveness in subsurface soil acidity reduction is limited. Thus, this review paper aimed to screen the tree species that easily overcome such problems. Scopus, Science Direct, Google Scholar, African journals online, and Google search engine databases were used. A total of 60 acidic soil-tolerant tree species were identified. Acacia auriculiformis, Acacia crassicarpa, Arbutus unedo L., Casuarina junghuhniana, and Erythrina abyssinica were among the extremely acidic soil-tolerant tree species. Whereas Acacia cincinnata, Acacia mangium, Pinus patula, Albizia saman, Citrus x paradisi, and Cassia reticulata were belongs to some of the strong acidic soil tolerant tree species. Generally, the species' acidic tolerance capacity and planting site compatibility should be considered for the success of amendment works. Scaling out these species and large-scale plantations should be done in addition to estimating their relative percent of acidic soil amendment roles. Producing stable food in line with reclaiming acidic soil is achieved through the integration of stress tolerant fruit trees. Research on large-scale plantations, domestication, skilling up and comparative evaluation of their levels of acidic soil amendment capacity should be performed in the future.

Optimizing Seed Germination of Acacia crassicarpa by Scarification and Plasma Fine Bubbles Treatments

The availability of appropriate methods to increase germination capacity (GC), thereby increasing the growth and vigor of seedlings in the nursery, plays an important role in the success of tree planting in industrial plantation forests. The aim of this research was to determine the effect of scarification and plasma fine bubbles (PFBs) treatments on the GC, viability, and vigor of Acacia crassicarpa A. Cunn. Ex Benth. seeds, one of the important acacias trees in industrial plantation forests. A completely randomized design with two factors, namely, scarification (soaking in 80°C to cold water for 24 h and 96% H2SO4 for 15, 20, and 25 min) and PFBs water treatment with ozone concentrations of 2 and 3 ppm for 5 and 10 min was used. Our study showed that the combination of scarification with H2SO4 solution for 25 min and 3 ppm PFBs water for 10 min gave the highest GC (90.75%), germination rate (GR) (20.28% days−1), and germination value (GV) (1.41). This combination also provided better results compared with methods widely used in industrial plantation forests by increasing GC 76.2%, GR 103.1%, and GV 291.7% and increasing hypocotyl length from 3.76 cm to 6.15 cm, radicle length from 2.24 cm to 6.31 cm, normal seedling length from 6.11 cm to 12.20 cm, and vigor index (VI) from 1.2 to 11.07 compared with control. This combination has been proven to increase germination, growth, and vigor of A. crassicarpa seeds; therefore, this treatment combination is recommended for use at the operational level of industrial plantation forests.

Illumina-based transcriptomic analysis of the fast-growing leguminous tree Acacia crassicarpa: functional gene annotation and identification of novel SSR-markers.

Acacia crassicarpa is a fast-growing leguminous tree that is widely cultivated in tropical areas such as Indonesia, Malaysia, Australia, and southern China. This tree has versatile utility in timber, furniture, and pulp production. Illumina sequencing of A. crassicarpa was conducted, and the raw data of 124,410,892 reads were filtered and assembled de novo into 93,317 unigenes, with a total of 84,411,793 bases. Blast2GO annotation, Benchmark Universal Single-Copy Ortholog evaluation, and GO-term classification produced a catalogue of unigenes for studying primary metabolism, phytohormone signaling, and transcription factors. Massive transcriptomic analysis has identified microsatellites composed of simple sequence repeat (SSR) loci representing di-, tri-, and tetranucleotide repeat units in the predicted open reading frames. Polymorphism was induced by PCR amplification of microsatellite loci located in several genes encoding auxin response factors and other transcription factors, which successfully distinguished 16 local trees of A. crassicarpa tested, representing potentially exploitable molecular markers for efficient tree breeding for plantation and biomass exploitation.

Longhorn beetles as new pests for exotic plantations in Vietnam

Longhorn beetles are important pests in commercial forests and exotic tree plantations worldwide, consequently leading to economic losses for timber producers and plantation owners. Acacia, Eucalyptus and Pinus plantations have been established widely in Vietnam for reforestation, wood products and paper industry. However, severe infestations of these three exotic trees have occurred due to longhorn beetles. The present study identified Coptops annulipes Gahan, 1894, Anagelasta apicalis Pic, 1925, Desisa subfasciata (Pascoe, 1862), and Cephalallus unicolor (Gahan, 1906) as four new longhorn beetles attacking Acacia crassicarpa in Quang Tri province, Eucalyptus hybrid (E. urophylla × E. grandis) in Bac Giang province, and Pinus caribaea in Quang Tri province, Vietnam. The infestation levels caused by C. annulipes, A. apicalis, D. subfasciata and C. unicolor were 16.8%, 29.5%, 39.2% and 24.3%, respectively. The damage indeces were 0.41, 0.85, 1.16 and 0.71, respectively. A. apicalis damaged at the base, C. annulipes and C. unicolor damaged at the lower trunk of host trees, D. subfasciata infested the top of trees. This information is expected to assist forest owners and government authorities across the country in pest surveillance and in developing suitable management plans for these four emerging pests.

Coppicing Abilities of Decapitated Elite Tree Trunks of Selected Acacia Species Genotypes in Mixed-Species Plantation

Maturation-related loss in the shooting and rooting ability of a species through macro or micropropagation techniques has been a limiting factor in any forest tree improvement program. The rejuvenation capacity of mature elite trees of Acacia mangium, Acacia crassicarpa, Acacia auriculiformis, and Acacia aulococarpa was investigated by evaluating the sprouting ability of decapitated trunks. Thus, a total of 120 trees were selected based on their superior phenotypic characteristics from four provenance and five progenies of each species, and trunks of the elite trees were decapitated into two different height groups to induce coppicing from the collar and base of the trunk. Coppicing ability varies with species, provenance, progeny, and cutting height. A. auriculiformis was the easiest to produce shoots by having the highest shooting percentage (84%) and the number of shoots per trunk (13.5), followed by A. mangium (75%) and A. aulococarpa (40%). The total shoot number increased significantly with the increase in the height of the stumps. Data indicated that there is a possibility to rejuvenate matured cutting through coppicing in the natural environment. This study will help in the standardization of the stumping procedure for the rejuvenation of elite Acacia genotypes while simultaneously assisting in preserving germplasm through clonal propagation.

First report of phyllode rust on Acacia crassicarpa outside its native range

AbstractAcacia crassicarpa is a tropical tree species native to Australia, West Papua and Papua New Guinea, which has been widely used to establish plantations in the lowland humid tropics of Sumatra and Kalimantan. These trees, able to grow on sites having relatively poor nutrition, have been relatively free of serious disease problems. A rust disease infecting the phyllodes of A. crassicarpa has recently been encountered in plantations in various areas of Indonesia and Malaysia where they are not native. In this study, the rust was collected and identified as Endoraecium violae‐faustiae using DNA sequence analysis based on the internal transcribed spacer (ITS) region of the rDNA. This is the first record of the rust outside its native range. Damage at present appears to be relatively mild but the pathogen could become important in the future.

Fabrication of activated carbon from Acacia Crassicarpa bark by carbothermal functionalization for adsorptive removal the dyes in aqueous solution

Activated carbon adsorbent prepared from Acacia Crassicarpa bark has been successfully synthesized via carbonization and chemical activation processes to investigate the elimination of hazardous dyes in industrial wastewater, specifically the anionic dye methyl orange (MO) and the cationic dye methylene blue (MB) in this study. The Acacia Crassicarpa bark was washed with distilled water and dried it in an electric oven at 100 °C. The carbonization process was carried out at a temperature of 1050 °C in the Argon atmosphere and thoroughly was activated by NaOH. The results showed that a high BET surface area of 711.05 m2/g was obtained. XRD pattern presented that the high content of crystalline carbon was formed and carbon content was achieved approximately 83%. Also, SEM images illustrated the average size of carbon is 2.58 μm and surface structure of activated carbon appeared the pores inside the particle. The Langmuir was observed to fit the adsorption data well. The maximum equilibrium adsorption capacities predicted by the Langmuir isotherm were found to be 156.25 mg/g and 144.09 mg/g for MO and MB, respectively. All of those results confirm that the activated carbon originated from Acacia Crassicarpa bark can potentially be applied for water purification treatment. In comparison to traditional charcoal, this activated carbon presents numerous advantages. Notably, it can integrate into the biomass energy cycle, improve filtration capabilities, and result in cost savings.

Financial Analysis of Beekeeping Practices at Acacia crassicarpa Plantation Forest in Riau Province, Indonesia

One environmental service provided by A. crassicarpa plantation is extrafloral nectar which has been widely used for beekeeping since 2019. Nevertheless, nowadays between apiaries practiced unfair competition since there were price fall led by oversupply and low demand after covid pandemic ended. Thus, evaluating the cost structure, profitability, and its feasibility value are critically required. The study's objectives were to 1) evaluate cost structure, revenue and profitability and 2) to conduct a feasibility analysis of each apiary type. This study was conducted from in 2019 to 2022 at the Siak Regency, Riau, Indonesia. Structure interviews combined with desk studies were carried out to collect the data. Data were analyzed based on cost structure, revenue, profitability, and feasibility analysis. All types of apiaries were feasible since they could cover variable and fixed costs. However, it revealed that all types of apiaries experienced minus in profitability in the fourth of financial year. In general, variable cost relatively increased to the level of 50% of total cost in the fourth year. In contrast, fixed cost was relatively declined to less than 50%. Apiaries managed two rits had a better performance in cost structure to face the competitive market followed by apiaries managed three rit. Meanwhile, apiaries managed rit one experienced such a difficult challenge to survive.

Uji Efektivitas Berbagai Surfaktan pada Insektisida Tenchu dalam Menanggulangi Hama Thrips sp. pada Tanaman Induk Acacia crassicarpa di Rumah Tanaman Induk Kerinci Central Nursery 1 East

The Nursery Department is the department responsible for ensuring the success of Acacia crassicarpa plants at an early stage by caring for and maintaining the quality and quantity of the seeds before planting them in the planting area. One of the disturbances that threatens the quality and quantity of seed production is the presence of Thrips sp. pest attacks. One of the Thrips sp. pest control techniques. with the application of insecticides with appropriate surfactants. Therefore, it is necessary to test various surfactants on Tenchu ​​20 SG insecticides which are appropriate in tackling Thrips sp. pest attacks. This study aims to determine the most appropriate surfactant in the Tenchu ​​20 SG insecticide in tackling Thrips sp. which attacks the mother plant Acacia crassicarpa. This research was conducted using a completely randomized design (CRD) with Least Significant Difference (LSD) follow-up test. The number of treatments in this study consisted of 5 treatments where each complete treatment with 3 repetitions used 72 sample plants so that the total sample plants used were 360 ​​plants. The parameters observed were the incidence and severity of Thrips sp.. The results showed that there was a decrease in the incidence and severity of Thrips sp. the largest is the type of Ronstick surfactant. The incidence rate and severity of Thrips sp. before application, namely 100% while after application, the incidence rate of Thrips sp. that is equal to 66.67% and the severity of Thrips sp. that is equal to 38.43%.

Screening the anthelmintic effects of leaves and fruits extracts from various Acacia species as a potential feed for small-ruminant animals

Abstract. Handayanta E, Hadi RF. 2023. Screening the anthelmintic effects of leaves and fruits extracts from various Acacia species as a potential feed for small-ruminant animals. Biodiversitas 24: 3140-3144. This study aimed to determine the anthelmintic properties of leaves and fruits obtained from various Acaciaspecies against Haemonchus contortus Rudolphi, 1803. Both leaf and fruit samples were allocated into five different groups: negative control (NC), 0.9% of NaCl solution; positive control (PC), albendazole solution; and solutions containing 12% concentration of each Acacia auriculiformis A.Cunn. ex Benth.(AA), Acacia mangium Willd.(AM), and Acacia crassicarpa A.Cunn. ex Benth.(AC) powder. The added concentration was set at 12%, and each treatment group was brought to incubation in 6 different time parameters (1, 2, 3, 4, 5, and 6 hours) against H. contortus. Each Acacia leaves extract did not significantly differ in eliminating H. contortus, unless for AM under 4 hours of incubation (p<0.05), wherein at the final incubation time, all Acacia-treated samples displayed complete mortality. Meanwhile, treatment with Acacia fruits during 6-hour incubations led to a removal of 76.66-83.33 % H. contortus population, in which Albendazole-treated groups showed complete mortality. Thus, this study suggested the leaves from Acacia are a potential animal feed as anthelmintic against H. contortus parasites. However, further studies investigating the potential mechanism by which various Acacia species present anthelmintic activity are necessary.

Net greenhouse gas balance of fibre wood plantation on peat in Indonesia

Tropical peatlands cycle and store large amounts of carbon in their soil and biomass1–5. Climate and land-use change alters greenhouse gas (GHG) fluxes of tropical peatlands, but the magnitude of these changes remains highly uncertain6–19. Here we measure net ecosystem exchanges of carbon dioxide, methane and soil nitrous oxide fluxes between October 2016 and May 2022 from Acacia crassicarpa plantation, degraded forest and intact forest within the same peat landscape, representing land-cover-change trajectories in Sumatra, Indonesia. This allows us to present a full plantation rotation GHG flux balance in a fibre wood plantation on peatland. We find that the Acacia plantation has lower GHG emissions than the degraded site with a similar average groundwater level (GWL), despite more intensive land use. The GHG emissions from the Acacia plantation over a full plantation rotation (35.2 ± 4.7 tCO2-eq ha−1 year−1, average ± standard deviation) were around two times higher than those from the intact forest (20.3 ± 3.7 tCO2-eq ha−1 year−1), but only half of the current Intergovernmental Panel on Climate Change (IPCC) Tier 1 emission factor (EF)20 for this land use. Our results can help to reduce the uncertainty in GHG emissions estimates, provide an estimate of the impact of land-use change on tropical peat and develop science-based peatland management practices as nature-based climate solutions.

Recent results from an ecohydrological study of forest species in drained tropical peatlands

Ecohydrological studies in tropical peatland have mostly focused on a small number of non-native commercial species. However, studies of native species are urgently needed as they are considered to be a possible solution in the restoration of millions of hectares of degraded tropical peatlands. We investigated peatland species on Padang Island, Indonesia, to assess their responses to changing environmental factors, particularly the high fluctuation of the water table due to intensive peatland draining. We monitored the sap-flux velocity and radial growth of six trees (four native and one non-native peatland species) in high temporal resolution using sap-flux meters and dendrometers up to seven months. Monitoring also included hydrological and micrometeorological parameters. We found that sap-flux velocity in the monitored species was mainly controlled by air vapor pressure deficits, photosynthetic active radiation, and to some extent, by wind speed and water-table depth. We also observed a species-specific correlation between daily sap-flux velocity and daily radial growth. Non-native Acacia crassicarpa had up to twice the radial growth of native species. This growth of non-native species was significantly higher at a shallow water-table depth, while native species did not show the same relationship. The interaction between water-table depth, sap-flux velocity, and radial growth in daily timescale was not straightforward, presumably because of the complex carbon-allocation mechanism in trees.

Quality Assessment on Honey Produced from Six Months Old Acacia crassicarpa

This study aimed to analyze the quality of Apis mellifera-produced honey generated from 6 mo old Acacia crassicarpa nectar at 28 d harvest period. The tests referred to the procedures required by the Indonesia National Standard (SNI) 8664-2018. The quality variables tested were of odor and taste and diastase enzyme activity as well as hydroxymethylfurfural (HMF), water, reducing sugar (glucose), sucrose, acid, water insoluble matter, and ash contents. The data were analyzed by using the student t test, where one sample group was prepared to compare each honey quality variable with the quality standard value. The results showed a distinctive smell and taste of honey, enzyme activity > 1.52 DN, HMF 0 mg kg-1, water content 24.2 % w w-1, reducing sugar content 66.56 % w w-1, sucrose content 1.50 % w w-1, acidity 113.05 NaOH kg-1, water insoluble matter content 0.018 % w w-1, and ash content 0.26 % w w-1. It is concluded that the quality variables for honey samples that met the quality requirements were odor and taste, HMF, reducing sugar, sucrose, water insoluble matter, and ash. Meanwhile, those that do not meet the quality requirements are the activity of the attached enzyme, water content and acidity.