Addition Of Organic Matter Research Articles

Organic material additions have stronger effects on humic substances and enzyme activities than soil types

AbstractThe incorporation of organic materials derived from plant biomass into various soils is an effective strategy for increasing soil organic carbon (SOC). The comparative effect of organic material forms and soil types on carbon (C) sequestration has received little attention. On a C equivalent basis, wheat straw, wheat straw‐biochar, tobacco straw, and tobacco straw‐biochar were added to different soil types such as acidic, saline, and calcareous and incubated for 180 days. The structural characteristics of SOC, humic substance (HS) contents, and enzyme activities were investigated, and it was discovered that the C content of crop straws and biochar was primarily fixed in the form of humin (HU) in all soil types. Furthermore, biochar application did not increase humic acid (HA), whereas crop straws treatments did. Between HU and SOC, there was a significant positive correlation. SOC Aryl C was increased by biochar treatments, whereas phenolic C and O‐alkyl C were increased by straw treatments. Aromatic C correlated positively with SOC concentration, whereas polyphenol oxidase activity correlated positively with O‐alkyl C. The activity of polyphenol oxidase influenced the ormation of O‐alkyl C significantly. The majority of SOC functional groups and enzyme activities were found to have significant relationships with HS contents (p value <0.05). These findings suggest that both soil types and organic materials influence HS and functional groups of SOC, with organic materials having a stronger influence on microbial activity than soil types. Biochar can be used for a wide range of soils to not only store more recalcitrant C but also make SOC more hydrophobic.

Potential energetic return on investment positively correlated with overall soil microbial activity

Microbial communities are a critical component of the soil carbon (C) cycle as they are responsible for the decomposition of both organic inputs from plants and of soil organic C. However, there is still no consensus about how to explicitly represent their role in terrestrial C cycling. The objective of the study was to determine how the molecular and energetic properties of readily available organic matter affect the metabolic activity of the resident microbial communities in soils. This was achieved by cross-amending six soils, taken from woodland and grassland sites along an urban pressure gradient, with organic matter extracted from the same six soils and measuring heat dissipated due to the increase in microbial metabolic activity. The energetic properties of the organic matter were used to estimate a potential energetic return on investment (ROI) that microbial communities could obtain from the transformation of the organic matter. Specifically, the ROI was calculated as the ratio between the total net energy available (ΔE) and the weighted average standard state Gibbs energies of oxidation half reactions of organic C (ΔG°Cox). ΔE was measured as the heat of combustion using bomb calorimetry. ΔG°Cox was estimated using the average nominal oxidation state of C (NOSC) of the molecular species in the organic matter. The overall metabolic activity of microbial communities was positively related to the potential energetic return on investment but no significant relationship was found with the molecular diversity of organic matter. The temporal differences in metabolism across soils indicate that bacterial communities do not exploit the potential energetic return on investment in the same way: the suburban grassland communities responded more rapidly and the suburban woodland communities more slowly to the organic matter additions than the other communities. The urban gradient did not affect the properties of the molecular or energetic properties of the organic matter nor the response of the microbial communities to the organic matter additions. However, the organic matter from the grassland soils caused soils to dissipate 36.4% more heat than organic matter from the woodland soils. The metabolic response was also more rapid after the addition of grassland organic matter: the time taken for half the heat to be dissipated was 6.4 h after the addition of grassland organic matter and 6.1 h after the addition of woodland organic matter. Overall, our results suggest that microbial communities preferentially use organic matter with a high potential energetic return on investment, i.e. organic molecules that do not require high cost associated with catalysis whilst yielding a high net energetic benefit.

Deciphering the Composition of Fulvic Acids from Recirculating Aquaculture Systems by Quadrupole Time-of-Flight Mass Spectrometry

The constant reuse of waters in recirculating aquaculture systems (RAS) together with the continuous addition of organic matter from fish degradation components, faeces and non-consumed feed promote the accumulation of dissolved organic matter (DOM), particularly of fulvic acids (FA), leading to the yellow discoloration of their waters. The accumulation of these acids in RAS can have potential effects on its water quality, and consequently fish health and welfare. Thus, the characterization of FA is paramount for improving water quality, and subsequently fish productivity in RAS. In this study, a non-targeted analysis by quadrupole time-of-flight mass spectrometry (QTOF-MS) was used to characterize the recirculating aquaculture systems fulvic acids (RASFA) and then compare their molecular fingerprints with actual reference standards of fulvic acids (FA) (Suwannee River; SRFA, Elliott soil; ESFA and Pahokee Peat; PPFA) purchased from the International Humic Substance Society (IHSS). The results of this study demonstrated the applicability of QTOF-MS as a rapid and comprehensive screening technique to characterize the FA fraction of DOM from RAS and to monitor differences in their molecular fingerprints when compared with other FA samples (SRFA, ESFA and PPFA). The QTOF-MS data from SRFA and ESFA standards matched the list of formulas obtained by 17 high-resolution mass spectrometry (HRMS) instruments with 90 and 76% accuracy, respectively, which guaranteed the power of QTOF-MS without the need for further coupling to liquid chromatography (LC). RASFA was found to be rich in low- and high-oxygen unsaturated classes of compounds (lowOC: 61.73% and highOC: 19.28%) and was similar in composition to SRFA. On the contrary, the ESFA and PPFA soil standards consisted mainly of aliphatic compounds (36.77 and 55.74%, respectively) and differed significantly in composition from the RASFA and SRFA water samples. RASFA matched with 66% of the elemental compositions obtained from the DOM of makeup waters analyzed in a previous experiment, indicating freshwater and seawater origins with a high fraction of terrestrial-derived organic matter (Tanimoto score: 0.53 between RASFA and SRFA). The unique information obtained from the molecular-level analysis of FA samples by QTOF-MS highlights the importance of this technique to characterize and compare FA from different origins rendering it possible to track the FA compositional changes along the water treatment processes of RAS. To our knowledge, this is the first study that characterizes the molecular fingerprints of the RASFA by QTOF-MS and compares them with the available FA reference standards from IHSS.

The effect of added organic matter on the soil formation of oil-based drill cutting pyrolysis residue.

In order to explore the effects of added organic matters on the soil formation process of oil-based drill cutting pyrolysis residue, two experiment groups (pure and adding) were studied to indicate the soil microbial community and the function of nitrogen cycling. Samples were collected in the third and fourth years based on the plant growth. The 16S rRNA high-throughput sequencing technology and PICRUSt were used to study microbial communities and the function of nitrogen cycling. The results showed that MND1 (2.5-4.5%), Sphingomonas (1.4-2.4%), and other typical oil-degrading bacteria were discovered. The diversity of the microbial community decreased with the duration of the experiment. However, it was higher than that of the background soil. The relative abundance of microbial nitrogen dissimilation reduction (0.9-1.0‰) was the highest among the two experiment groups and the background soil. The second and third were denitrification and nitrogen fixation. Nitrification gene abundance was the lowest among the five main steps of nitrogen cycling. The addition of organic matters could improve soil formation of pyrolysis residues. This study provides scientific data for pyrolysis residue to restore soil functions.

Microbial iron reduction and greenhouse gas production in response to organic matter amendment and temperature increase of periglacial sediments, Bolterdalen, Svalbard

ABSTRACT Arctic permafrost soils store substantial reserves of organic matter (OM) from which microbial transformation contributes significantly to greenhouse gas emissions of CH4 and CO2. However, many younger sediments exposed by glacier retreat and sea level change in fjord landscapes lack significant organic carbon resources, so their capacity to promote greenhouse gas emissions is unclear. We therefore studied the effects of increased temperatures (4°C and 21°C) and OM on rates of Fe(III) reduction, CO2 production, and methanogenesis in three different Holocene sedimentary units from a single site within the former marine limit of Adventdalen, Svalbard. Higher temperature and OM addition generally stimulated CH4 production and CO2 production and an increase in Bacteria and Archaea abundance in all units, whereas an equal stimulation of Fe(II) production by OM amendment and an increase in temperature to 21°C was only observed in a diamicton. We observed an accumulation of Fe(II) in beach and delta deposits as well but saw no stimulating effect of additional OM or increased temperature. Interestingly, we observed a small but significant production of CH4 in all units despite the presence of large reservoirs of Fe(III), sulfate, and nitrate, indicating either the availability of substrates that are primarily used by methanogens or a tight physical coupling between fermentation and methanogenesis by direct electron transfer. Our study clearly illustrates a significant challenge that comes with the large heterogeneity on a narrow spatial scale that one encounters when studying soils that have complex histories.

Synergistic effects of straw and earthworm addition on microbial diversity and microbial nutrient limitation in a subtropical conservation farming system

Conservation farming systems with straw return and no-tillage are recommended as effective methods for soil quality improvement, and they are often accompanied by increases in soil fauna populations. Recently, attempts have been made to improve the soil fertility in conservation agriculture through enhanced bioturbation by adding earthworms to no-till fields. However, the mechanisms associated with the responses in terms of soil functions, such as microbial diversity and microbial nutrient metabolism, to the synergistic effects of biotic and abiotic factors remain unclear. In this study, plow layer and plow pan soils were collected from subtropic cropland, and a full factorial microcosm experiment was conducted to quantify the effects of straw mulching and adding earthworms on the soil nutrient contents, microbial diversity, and extracellular enzymatic activities. The results showed that the single application of straw significantly increased the soil organic carbon (C), the ratio of C to nitrogen (N), and the ratio of C to phosphorus (P) in the plow layer soil (p < 0.05). The combined addition of straw and earthworms significantly increased the microbial diversity (Observed species, Chao 1 and Shannon), C/N/P-acquiring enzymatic activities, and microbial C limitation (p < 0.05), but decreased the microbial P limitation (p < 0.05) in the plow pan soil. Adding straw or earthworms did not affect the soil nutrient content in the plow pan soil (p > 0.05), microbial diversity, C-acquiring enzymatic activities, and microbial C and P limitations in the plow layer soil (p > 0.05). Structural equation models indicated that straw mulching indirectly affected the soil microbial diversity and microbial nutrient limitation through the buffering effects of aggregate stability and the C/P ratio in the plow layer soil. By contrast, the soil microbial activities were directly influenced by straw and earthworm addition in the plow pan soil. These findings indicate that earthworms enhanced soil microbial metabolism when straw was added by improving the substrate availability, and the soil physicochemical properties determined the asynchronous responses of the soil functions to land management. We suggest that the combined addition of organic matter and earthworms can improve the quality of soil in infertile land.

Trace Elements Uptake in Brassica rapa chinensis Cultivated in Ultrabasic (Oxisol) and Ultisol Soils, North Borneo

The study aims to investigate the soil physico-chemical properties and trace elements uptake of Brassica rapa chinensis plants cultivated in ultrabasic (oxisol) and ultisoil soil of Ranau, North Borneo, Malaysia by inductively coupled plasma-optical emission spectrometry (ICP-OES). This study can contribute to propose a more sustainable soil management practice. All selected trace elements bioavailability in ultrabasic soil was significantly higher than ultisols except for Ca and Cd. There was no significant amount of difference in soil pH (slightly acidic) and electrical conductivity (slightly saline) between these soil types. However, a significant amount of difference between the percentage of soil moisture and organic matter between ultrabasic and ultisol soils was observed. These might contribute to the uptake of elements into the studied plant. The B. rapa chinensis is a hyperaccumulator of Cd and Pb for both type of soils. The B. rapa chinensis is an accumulator of As when grown in ultrabasic soil, while an accumulator of Co when grown in ultisol soil. Although Pb was not detected in ultisol soil as compared to ultrabasic soil, the concentration of Pb in plants cultivated in ultisol soil had exceeded the maximum permissible limit of Malaysia Food Regulation 1985. Soil amendment in frequently use agriculture sites needs to be conducted such as the addition of organic matter to reduce transfers of trace elements from soil to plants that can pose toxicity risk.

Role of composted organic material in reducing hazardous effect of salinity stress on biological nitrogen fixation and plant growth in salt affected soils of arid region

Application of organic matter (OM) has shown positive effects on growth and yield of crop grown under soil salinity stress. The present study was conducted to estimate effectiveness of OM in enhancing Biological Nitrogen Fixation (BNF) in soil and in return improving growth and yield of cowpea. Therefore, role of (OM) in alleviating impact of salinity stress on (BNF) in soils of arid region was evaluated in medium textured soils of different content of salts content. Experiment was conducted in pots under greenhouse conditions. Salinity range studied was 3.5, 8.2 and 12.4 dSm-1 in J1, J2, and J3 soil respectively. Compost as OM was added at 15, 25 and 50 g Kg-1 soil. Cowpea local variety was used as a test crop. Total nitrogen in soils without the addition of organic matter after harvesting was the least at the highest salinity level and the highest was in the soil of the least salinity level. Number of root nodules reduced by 27.0% and 49.0% when soil salinity increased to 8.2 and 12.4 dSm-1, respectively, compared to that in soil of 3.5 dSm-1. Total N in Cowpea plant linearly increase with the increase of level of (OM) addition. Rate of Increase in total N was the highest at the lowest salinity level soil and was the least at the highest salinity level soil. Weight of root nodules decreased by 45% when soil salinity increased by 42%. Addition of OM at a rate of 25 g OM Kg-1 soil to J1 soil of (3.5 dSm-1) and soil J3 of 12.4 dSm-1 weight of root nodules increased by 47.0%. and 21.7%, respectively. Dry weight of Cowpea plant grown in the three soils received different levels of OM decreased with the increase of soil salinity irrespective of level of OM addition. Addition of OM at a rate of 15, 25, and 50 g kg-1 soil of 3.5 dSm-1 seed yield increased by 65%,130%, and 136% respectively. These results had confirmed the role of OM in alleviating salinity stress on BNF process in soil.

OPTIMALISASI BIOGAS DARI KOTORAN SAPI DENGAN PENAMBAHAN BAHAN ORGANIK DARI LIMBAH PERTANIAN DAN PASAR

Cow farm waste is one type of raw material that is commonly used in biogas formation technology. According to 1 Wahyuni (2013), a cow can produce fresh waste between 20 to 29 kg/day. According to 2 Kaharudin and Sukmawati (2010), biogas on a household scale with a number of livestock of 2-4 cows or a supply of dung of approximately 25 kg/day is sufficient to use a reactor tube with a capacity of 2500-5000 liters which can produce biogas equivalent to 2 liters of oil. land/day and is able to meet the energy needs of one rural household with 6 family members. The higher the organic matter content in biogas technology, in a suitable environment, the biogas production will increase. This causes the need for the addition of mixed organic matter so that biogas production is maximized. The type of organic material used is a very important factor. Grass, rice straw or vegetable waste can be used as a source of organic matter in the biogas production process.

Gelatin Methacryloyl Hydrogels for Musculoskeletal Tissue Regeneration.

Musculoskeletal disorders are a significant burden on the global economy and public health. Hydrogels have significant potential for enhancing the repair of damaged and injured musculoskeletal tissues as cell or drug delivery systems. Hydrogels have unique physicochemical properties which make them promising platforms for controlling cell functions. Gelatin methacryloyl (GelMA) hydrogel in particular has been extensively investigated as a promising biomaterial due to its tuneable and beneficial properties and has been widely used in different biomedical applications. In this review, a detailed overview of GelMA synthesis, hydrogel design and applications in regenerative medicine is provided. After summarising recent progress in hydrogels more broadly, we highlight recent advances of GelMA hydrogels in the emerging fields of musculoskeletal drug delivery, involving therapeutic drugs (e.g., growth factors, antimicrobial molecules, immunomodulatory drugs and cells), delivery approaches (e.g., single-, dual-release system), and material design (e.g., addition of organic or inorganic materials, 3D printing). The review concludes with future perspectives and associated challenges for developing local drug delivery for musculoskeletal applications.

Effect of Organic Material Amendments on Soil Respiration in Tobacco Fields of Central Henan

A field experiment was conducted to study the effects of different organic material amendments on soil respiration in a flue-cured tobacco field. Five treatments were set up:no fertilizer (NF), chemical fertilizer (NPK), chemical fertilizer+ryegrass (NPKG), chemical fertilizer+wheat straw (NPKS), and chemical fertilizer+tobacco straw biochar (NPKB). The results showed that:① Compared with that under NPK, NPKG and NPKS decreased the temperature sensitivity (Q10) of total soil respiration and heterotrophic respiration, whereas NPKB increased the Q10 of heterotrophic respiration. The two-factor fitting model of soil respiration and soil hydrothermal factors accounted for 50%-80% of the variation in soil respiration. ② The addition of organic materials significantly increased the content of soil soluble organic carbon (DOC) and root dry matter. Soil heterotrophic respiration(Rh) was significantly positively correlated with DOC content, and soil autotrophic respiration(Ra) was significantly parabolically correlated with root biomass, with an R2 of 0.327-0.634. ③ Soil respiration increased first and then decreased during the tobacco growth period. Compared with that under the NF treatment, the NPK treatment significantly promoted soil respiration and its components. Compared with those of the NPK treatment, Rsrates were significantly increased by 20.08%, 10.32%, and 9.88% under the NPKG, NPKS, and NPKB treatments, respectively; Rh rate increased by 24.21%, 16.51%, and 11.68% respectively, and Ra rate was increased by 15.12% in the NPKG treatment. In summary, straw returning and biochar addition significantly increased Rh by increasing soil DOC, thereby promoting Rs. Incorporation of ryegrass not only increased the Rh but also increased Ra by promoting the growth and development of roots and therefore the Rs.

Micronutrient Status in Commercial Sugarcane-growing Alfisols at &lt;em&gt;Sevanagala&lt;/em&gt;, Sri Lanka

The continuous mono-culture cropping without organic matter addition could deplete the plant available micronutrient reserves in sugarcane-growing soils. This study attempted to investigate the current status of micronutrient availability in commercial sugarcanegrowing Alfisols at <em>Sevanagala</em>, Sri Lanka, and to assess the potential of these soils to become micronutrient deficient in the future. Sugarcane-growing Alfisols at <em>Sevanagala</em>, covering both irrigated and rain-fed cropping systems, and low humic gley (LHG) and reddish-brown earth (RBE) soils were included in this study. A stratified random sampling technique, covering both cropping systems and soil orders, was employed to obtain 263 samples. Soils were analyzed for available Fe, Mn, Zn, and Cu contents using the standard DTPA procedure. Available Fe and Zn contents exhibited significant differences among cropping systems and soil orders. They were significantly higher under RBE soil (75 mg/kg and 1.1 mg/kg in Fe and Mn, respectively) when compared to those under LHG soil (43 mg/kg and 0.6 mg/kg in Fe and Mn, respectively). Available Fe and Mn contents were at sufficient levels for sugarcane in most soils. In contrast, Zn and Cu contents exhibited deficient patches (&lt; 0.1 mg/kg) within the cropping systems and great soil groups in the studied area. The results indicate that appropriate nutrient management practices are required to overcome Zn and Cu deficiencies in <em>Sevanagala</em> sugarcane-growing Alfisols and to mitigate any negative effects on crop yield and quality in the future.

Morphophysical and Nutrient Characteristics of Degraded Soils in Sta. Rita, Samar, Philippines

The productivity of degraded soils greatly depends on a good understanding of their characteristics. Hence, the study was conducted to determine the morphological, physical and chemical characteristics of degraded soils in Sta. Rita, Samar, Philippines. Four representative soil profiles located in different physiographic positions were examined, characterized and sampled. The examination was conducted using a pit measuring approximately 1-m wide and 1-m depth. Soil samples were collected from each horizon, processed and subjected to field and laboratory analyses. Results showed that the soils were derived from sedimentary rocks (i.e., shale). Well-developed soils were found on the summit and foot slope position (horizon sequence: Ap-Bt-BC-C), while moderately developed soils were obtained in the middle slope position (horizon sequence: Ah-Bt-C). Soils had a clayey texture with moderate bulk density, porosity and water holding capacity. They were friable to firm when moist, but plastic and sticky when wet. The soils were highly acidic (soil pH close to 5.0). They had a moderate amount of organic matter, low total nitrogen (N) and low available phosphorus (P); all of which had decreased amounts with soil depth. Exchangeable bases (calcium, magnesium, potassium and sodium) were high in most soil profiles. Thus, N and P fertilization and organic matter addition are highly recommended to increase the productivity of these degraded soils. Moreover, the soils were classified as Typic Hapludalfs or Haplic Luvisols because of their development degree. They were mature with the presence of an argillic horizon (B horizon with high clay accumulation) and high base saturation.

The role of mycorrhiza in food security and the challenge of climate change

Before the Industrial Revolution, the concentration of CO2 in the atmosphere was 280 ppm and in time increasing fossil fuels use increased CO2 concentration up to 416 ppm in a preset time. Meanwhile, increasing population growth (around 8 billion) has also started to put serious pressure on soil ecosystem for more food production demand. With the demand for more food production, intensive chemical inputs and soil cultivation practices applied to the soil has increased the amount of CO2 released to the atmosphere. Increasing CO2 concentration in the atmosphere triggers global warming and climate change which is negatively affect plant growth and consequently food security. In order to ensure food security under climate change conditions, it seems that the need to re-enact nature's own mechanisms has arisen. In this context, it is aimed to reduce the effect of climate changes by keeping more carbon as a sink by operating the effects of plant root mechanisms on the soil health according to ecological principles. Under long term filed conditions the effects of different soil-plant managements, especially mycorrhiza fungi, were investigated. Since 1996, several researches have been carried out under long-term field studies to see the effect of mycorrhizal fungi and other microorganisms on carbon sequestration, as well as the emission of CO2 from the greenhouse gases to the atmosphere. Regularly CO2 flux, emissions, photosynthesis rate, C, N sequestration and yield parameters are measured. Data are yearly evaluated. Results revealed that under long-term field conditions, organic fertilizers application and mycorrhizal inoculation sequestered more carbon in soil profile. It has been shown that, using animal manure, compost, biochar, nitrogen-fixing bacteria and mycorrhizal fungi significantly kept more carbon in plant tissue and soil. It is determined that there is an increase of 1.5 ppm CO2 concentration in atmosphere per year. It has been determined that especially long-term addition of organic matter and management of natural mycorrhizae increase soil organic carbon and accordingly soil quality and productivity increase. As the effect of climate change and population growth have significant negative impact on food security, definitely a new agriculture revelation is needed to overcome of climate and food security problem. Soil and plant management must be managed according to low-input ecological principles.

Metal Lability and Mass Transfer Response to Direct-Planting Phytostabilization of Pyritic Mine Tailings.

Understanding the temporal effects of organic matter input and water influx on metal lability and translocation is critical to evaluate the success of the phytostabilization of metalliferous mine tailings. Trends of metal lability, e.g., V, Cr, Mn, Co, Ni, Cu, Zn, and Pb, were investigated for three years following a direct-planting phytostabilization trial at a Superfund mine tailings site in semi-arid central Arizona, USA. Unamended tailings were characterized by high concentrations (mmol kg-1) of Fe (2100), S (3100), As (41), Zn (39), and Pb (11), where As and Pb greatly exceeded non-residential soil remediation levels established by Arizona. Phytostabilization treatments included a no-compost control, 100 g kg-1 compost with seed, and 200 g kg-1 compost with and without seed to the top 20 cm of the tailings profile. All plots received supplemental irrigation, effectively doubling the mean annual precipitation. Tailings cores up to 90 cm were Collected at the time of planting and every summer for 3 years. The cores were sub-sectioned at 20 cm increments and analyzed via total digestion and an operationally defined sequential extraction for elemental analysis and the calculation of a mass transfer coefficient normalized to Ti as an assigned immobile element. The results indicate that Pb was recalcitrant and relatively immobile in the tailings environment for both the uncomposted control and composted treatments with a maximum variation in the total concentration of 9-14 mmol kg-1 among all samples. Metal lability and translocation above the redox boundary (ca. 30 cm depth) was governed by acid generation, where surficial pH was measured as low as 2.7 ± 0.1 in year three and strongly correlated with the increased lability of Mn, Co, Ni, Cu, and Zn. There was no significant pH effect on the lability of V, Cr, or Pb. Translocation to depths was greatest for Mn and Co; however, Zn, Ni, Cr, and Cu were also mobilized. The addition of organic matter enhanced the mobilization of Cr from the near surface to 40-60 cm depth (pH > 6) over the three-year phytostabilization study compared to the control. The increased enrichment of some metals at 60-90 cm indicates that the long-term monitoring of elemental translocation is necessary to assess the efficacy of phytostabilization to contain subsurface metal contaminants and thereby protect the surrounding community from exposure.

The effect of manure and ascorbic acid to the growth of Vetiveria zizanioides L. in saline soil

Vetiveria zizanioides was known as vetiver that produces a good quality oil and is also competent in foreign markets. This study aims to determine the effect of manure and ascorbic acid on the growth of vetiver on saline soil by applying the appropriate dose of manure and ascorbic acid for optimal growth. The methodology was done using a randomized block design with three replicates and consisted of 2 factors, i.e., manure level (K) and the ascorbic acid concentration (A). The results suggested an interaction of the manure and ascorbic acid concentration in the plant height, root volume but not found in the number of clumps. The manure displays a significant response to plant height, number of leaves, number of clumps, and root volume. The ascorbic acid response to the growth was obtained to the best response in plant height, a number of leaves, and root volume. The dose of manure and ascorbic acid that increased concentration was suspected to control salinity stress. The manure was thought to be able to provide the organic matter in saline soil because the addition of organic matter holds water and retains nutrients. Besides, ascorbic acid has been a role antioxidant during plant stress.

Perbaikan Sifat Kimia Lahan Bekas Tambang Emas Melalui Aplikasi Biochar Sekam Padi dan Pupuk Kandang Ayam

Improvement of Chemical Properties of Ex-Gold Mine Land Through Application of Rice Husk Biochar and Chicken Manure. Ex-gold mining land that have been degraded so that soil fertility is very low. Mining with an open system causes an increase in the oxidation of sulfuric minerals which reduces nutrient levels, so it is necessary to make efforts to increase nutrients through the addition of rice husk biochar and manure. The purpose of the study was to determine the role of rice husk biochar and manure to improve soil chemical properties. This study used a completely randomice design (CRD)with 6 treatments and 4 replications. The results showed that 100% manure treatments could increase soil fertility, when the soil pH was 6.28, total N 0.0072%, and available P 59.74 ppm. The best treatments for the organic C parameter is a combination of 50% rice husk biochar + 50% manure, which is 1.42%. Based on research, the addition of organic matter can improve the chemical properties of ex-gold mining land.

Comparison Of Jakaba Growth With The Addition Of Organic Matter In Rice Washing Water

Jakaba (perennial luck mushroom) is a fungus derived from the fermentation of rice laundry water (leri). This fungus has the same physical shape as coral but has a fragile texture. This study aims to find out the growth of jakaba with the addition of organic matter in rice laundry water. The research was conducted in Padang Halaban village, Aek Kuo District, Labuhan Batu Utara Regency, North Sumatra. The research was conducted by mixing 1 liter of leri water with 400 grams of organic ingredients such as bran, banana peel and catfish feed Research was carried out by repeating each treatment as much as 6 repetitions with the parameters of salting, namely aroma, color, growth and diameter of jakaba. Based on observations, it is known that the growth of jakaba fungus occurs on the 12th day to the 15th day with the largest jakaba diameter which is 52.9 mm (P2) and the smallest is 40.25 mm (P1). The addition of other organic matter to leri water gives a different aroma and color of jakaba to each treatment.

Study of Organic Fertilizers and Rice Varieties on Rice Production and Methane Emissions in Nutrient-Poor Irrigated Rice Fields

The problem of rice farming in Indonesia is the increasing extent of nutrient-poor land due to the lack of addition of organic matter and continuously inundated irrigated rice fields, causing the production of greenhouse gas emissions, such as methane gas (CH4), to increase. The study aims to determine the impact of organic fertilizers and rice varieties on rice yield, methane emissions, and the feasibility of farming in nutrient-poor rice fields. The study used a randomized block design in factorial with four replicates. The first factor is the type of organic fertilizers (compost of rice straw and goat manure), and the second factor is the variety of rice (Ciherang, Inpari 20, and Inpari 30). The results showed that the productivity of Inpari 20 (8.02 t·ha−1) was significantly higher than that of Inpari 30 (6.10 t·ha−1) and Ciherang (6.91 t·ha−1). The highest yields of Harvest Dry Grain (HDG) to Milled Dry Grain (MDG) were the Inpari 20 (88.23%), Inpari 30 (86.94%), and Ciherang (85.04%). Methane (CH4) emissions were highest in the Ciherang variety (56.4 kg h−1 season−1), followed by Inpari 30 (40.8 kg h−1 season−1), and lowest in Inpari 20 (22.3 kg h−1 season−1). Compared to Inpari 30 and Ciherang varieties, the Inpari 20 variety with rice straw compost has broad development viability in nutrient-poor paddy fields (highest R/C ratio and break-even point). More research on organic rice is needed to determine the productivity and emissions (methane, nitrite, carbon dioxide).

Evaluation of operating parameters affecting the two-stage nitritatin/anammox process in mainstream flows: From lab-scale to pilot-scale

Operating parameters for the two-stage nitritation/anammox (PN/A) process in mainstream flows from lab-scale to pilot-scale were investigated. In the batch experiment, the specific activities of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) were fitted with a Monod model, and the oxygen affinity of NOB was higher than that of AOB. Nevertheless, dissolved oxygen concentrations higher than 2.0 mgO2/L were effectively applied for selective inhibition of NOB. In addition, organic matter was evaluated as the operating parameter that inhibited the activity of NOB more selectively than AOB under mainstream conditions. The operating parameters determined in the batch experiment were verified in a continuous experiment, and it was shown that the shortening of hydraulic retention time with increasing aeration time in the sequencing batch reactor cycle has the potential to selectively enhance the activity of AOB over NOB. The effect on the C/N ratio and temperature in a lab-scale anammox reactor was investigated. The denitrification with the addition of organic matter contributed to the improvement of nitrogen removal efficiency, but a C/N ratio of more than 1.0 severely deteriorated the sludge settleability. The operating factors for the mainstream PN/A determined in the lab scale were applied to the pilot plant. As a result, a nitrogen removal efficiency of 79 ± 11% was stably achieved with effluent total nitrogen of 2.6 ± 1.5mg/L. However, unpredictable fluctuations in environmental factors revealed that residual ammonium was another critical factor affecting mainstream PN/A.