Irreversible Drying Research Articles

Analysis of Drought Index and Soil Infiltration to Control Fire Risk in Tropical Peatland Forest

Peatlands in Indonesia cover an area of more than 7% of the land area, around 14.95 million hectares spread over the islands of Sumatra, Kalimantan, Papua, and a small part of Sulawesi. Peatlands are made use of by establishing a drainage system and clearing land. Due to the peatland’s inability to absorb water, land fires and irreversible drying are all consequences. This also takes place in a protected forest in Liang Anggang Protected Forest. The purpose of this study is to reduce the risk of fire in Liang Anggang Protected Forest by establishing a correlation between the drought index on peatlands and infiltration data. Based on an understanding of the hydrological processes that occur in peatlands, which are characterized by reduced rainfall, high drought index values, and the soil’s ability to absorb water, especially in the dry season. From June to October, especially in September, the soil is very dry. It is vulnerable to fire. Extreme caution is required in the land management process with fire from the citizens around the area.

Growth response and nutrition uptake of corn plants on drought stress in peat soil

Peat soil has been exposed to drought so it cannot bind water (irreversible drying) and loses its function as soil. Peat soil will be dry organic soil cannot provide water to plants. In addition, drought stress as abiotic stress decreased the ability of the soil to hold roots so that plants can fall easily which is impacted by changing the physical and chemical properties of peat soil. The goal of this research was to acquire biofertilizer components that are optimized for increasing corn in drought-stress land and the sustainability of peat soils. This study was conducted inside the experimental land of Universitas Bina Insan, Lubuklinggau. The layout used in this study became a factorial randomized block design with two elements. The first element has been the biofertilizer method (F) with four stages, specifically: F0 = without mycorrhizae, F1 = Mycorrhiza + Petrobio, F2 = Mycorrhiza + Agrozeabiochar, F3 = Mycorrhiza + Pugam. The second element was the intensity of watering (P) includes 4 ranges, particularly: watering once a day, P2 = watering every three days, P3 = watering every five days, and P4 = watering every seven days. The results showed that the biofertilizer formula with mycorrhizal+petrobio (F1) treatment has significant effects in increasing plant height, plant dry weight, and nutrient uptake. Enhancement of nutrient uptake correlated with increasing the growth of corn plants on drought stress in peat soil, The intensity of watering, was significantly different in all treatments except for K nutrients uptake.

The Physical Property Changes of Peatland upon Conversion of Oil Palm Plantation to Corn Cropping in Kinali, West Pasaman, West Sumatera

The decrease in oil palm production in Kinali, West Pasaman Regency, has become the factor that makes the farmers convert their peatlands to corn cropping. This study aimed to examine the physical characteristics (irreversible drying) of peatlands due to the conversion of oil palm to corn cropping. Some observations and samplings were conducted by applying a transect method, as it was perpendicular to the collection drain for 2, 200, and 400m from the main drains in three locations as the uses of the lands: (1) oil palm plantations, (2) <2-year corn cropping, (3) >2-year corn cropping. In each land, 3 sample points were taken with 2 repetitions at a depth of 0‒20 cm and 20‒40 cm. The physical properties of peatlands that have been converted from oil palm plantations to corn cropping include the water content increasing from 286.4 to 348.5 and 322.7%, the ash content decreasing from 55.2 to 43.5 and 47.5%, with C-organic increased by 25.9 to 30.7 and 32.4%, fiber content increased from 27.1 to 32.1 and 28.7%, and the volume weight of the peat tended to be similar (0.3 g/cm3). In all land use, irreversible drying occurred; in the oven at 50°C dan 70°C with a drying time of 3´24 hours, and at 150°C, and the drying time of 1´24 hours, the moisture content of 232‒256% in oil palm plantation, 269‒290% in <2-year corn cropping, and 394‒440% in >2-year corn cropping. Irreversible drying occureds more quickly on the peatlands in oil palm plantations rather than in corn cropping.
 
 Keywords: corn cropping, irreversible drying, palm oil plantation, peatland

Peatland water conservation by agroforestry system

Peat swamp forest have a high economic value and are potential for agricultural development. However, peatlad are fragile ecosystems because they are easily damaged and difficult to restore. The main problem of all peat soil types is their irreversible drying. In this condition the peat soil is easy burning, unable to store water, and if the groundwater is far from the surface, the plants will be stressed from lack of water. Therefore to support sustainable agricultural development on peatlands it requires careful planning, application of appropriate technology and suitable management. One of the land management systems that can be applied on peatlands is combining agricultural crop and forest plant (agroforestry). Forest plant and seasonal agriculture crops can increase CO2 absorption so that photosynthetic efficiency and oxygen production increase. These proses increase the production of biomass which can maintain soil organic matter and prevent erosion. Organic matter enhance the effectiveness of rewetting and water retention capacity. In addition, this system also affects the microclimate, such as the soil becoming more humid because it gets shade from the vegetation above it, so reduce temperature and elevated air moisture. Indirectly, agroforestry can reduce excessive evaporation and maintains the ground water level, especially during the dry season. This review aim to explain the role of intercropping system in peatland water conservation.

INTENSITAS KEBAKARAN LAHAN GAMBUT BERDAMPAK PADA KEMASAMAN TANAH DI KEBUN KELAPA SAWIT, KABUPATEN TULANG BAWANG, PROVINSI LAMPUNG

Peatlands have specific characteristics, namely irreversible drying, so that become flammable. Peat fires have an impact on changes in soil pH. The study aimed to analyze the soil acidity after peatland fires in oil palm plantation. This study used a survey method on two main plots (low and high fire intensity). Samples were taken at two soil depth including 0-10 cm and 11-30 cm in three zones (fertilization area, harvest path and frond pile zone) and repeated three times. Data were analyzed by ANOVA using the 5% nested test, then LSD test, and analyzed for correlation. The results showed that the soil pH on all land was included in the very acid category. Soil pH in the land B (land with high fire intensity) is higher than those in the land A (land with low fire intensity), both in top soil and sub soil. The micro-nutrient elements of Fe and Al in the land B are lower than land A, while the micro-nutrients of Mn in land B are higher than land A. The correlation of soil pH towards Fe and Al is negative, while for Mn is positive (pH increases, acid cations of Fe and Al will decrease while acid cations of Mn will increase). This was presumably due to competition in occupying the land-catchment complex.

Predicting peatland groundwater table and soil moisture dynamics affected by drainage level

Excessive drainage of peatlands can cause subsidence and irreversible drying; therefore, it is necessary to predict groundwater levels in peatlands to ensure adequate water for crops and control excessive water loss simultaneously. This study aimed to predict the peatland groundwater level and soil moisture affected by drainage. This research was conducted in a peatland located in Rasau Jaya Umum, Kubu Raya Regency, West Kalimantan Province, Indonesia from February to December 2016. Three treatments of drainage setting were established with maize cropping: without drainage (P0) and drainage channel with water level maintained at depths of 30 cm (P1) and 60 cm (P2) from the soil surface. The results indicated that a polynomial regression model is a good approach to predicting groundwater table level and soil moisture in peatlands, with R<sup>2</sup> values ranging 0.71-0.96 and 0.65-0.93, respectively. For agricultural purposes, maintaining the water level at 30 cm from the soil surface in the drainage channel appears to be the ideal level as adequate soil moisture is provided for annual cash crops and drying is prevented simultaneously.

A critical contribution on understanding the mechanism and implication of peat irreversible drying

The term irreversible drying is known as a condition when peat soil material is dry and cannot be re-wet after an intensive drying. This condition is a result of peat soil hydrophobicity that occurs when a contact angle between peat soil particles and water is greater than 90° and is always understood to be associated with water content. However, in South Kalimantan, there was a phenomenon of irreversible drying but soil water content was still around field capacity and there was a visible coating substance on the particle surface. The purposes of this study were 1) to clarify the cause of irreversible drying in this location and 2) to show a possible effect of rock phosphate addition on the hydrophobicity’s disappearance. A hydrophobic peat soil sample was taken from the location that is cultivated for oil palm. Field observation was conducted on the peat soil that had been amended by rock phosphate. The peat soil hydrophobicity was identified by the Water Drop Penetration Time method and the surface coating substance was observed using SEM-EDS. The WDPT result shows that the peat soil was in hydrophobic condition, but the water content was still around field capacity. The results from SEM-EDS indicate that the coating substance was found as sulfate salts. The rock phosphate that had been added in the field shows a positive effect on the disappearance of the peat irreversible drying. However, the mechanism of soil properties change due to rock phosphate cannot be confirmed yet and need further investigation.

Progress and challenges in consolidating the management of Amazonian protected areas and indigenous territories.

Effective management refers to the ability of a protected area or indigenous territory to meet its objectives, particularly as they relate to the protection of biodiversity and forest cover. Effective management is achieved through a process of consolidation, which among other things requires legally protecting sites, integrating sites into land-use planning, developing and implementing management and resource-use plans, and securing long-term funding to pay for recurrent costs. Effectively managing all protected areas and indigenous territories in the Amazon may be needed to avoid a deforestation tipping point beyond which regional climatic feedbacks and global climate change interact to catalyze irreversible drying and savannization of large areas. At present, protected areas and indigenous territories cover 45.5% (3.55 million km2 ) of the Amazon, most of the 60-70% forest cover required to maintain hydrologic and climatic function. Three independent evaluations of a long-term large-scale philanthropic initiative in the Amazon yielded insights into the challenges and advances toward achieving effective management of protected areas and indigenous territories. Over the life of the initiative, management of sites has improved considerably, particularly with respect to management planning and capacity building, but few sites are effectively managed and many lack sufficient long-term financing, adequate governance, support of nongovernmental organizations, and the means to withstand economic pressures. The time and money required to complete consolidation is still poorly understood, but it is clear that philanthropic funding is critical so long as essential funding needs are not met by governments and other sources, which could be on the order of decades. Despite challenges, it is encouraging that legal protection has expanded greatly and management of sites is improving steadily. Management of protected areas in other developing countries could be informed by improvements that have occurred in Amazonian countries.

The changes of soil physical and chemical properties of Andisols as affected by drying and rewetting processes

Soils from a toposequence in northern slope of Mt. Kawi, Malang were sampled to study the effect of amorphous content on the irreversible drying properties of the soils. Water, clay, organic-C, and available P contents were measured at field capacity (KL), after air-drying for 2 days (K2) , air-drying for 4 days (K4), oven-drying at 40 °C for 1 day (Ko), as well as after rewetting K2 (KL2); K4 (KL4), and Ko (KLo). The results showed that water, clay, organic-C, and available P contents changed after drying and rewetting processes. Drying process decreased clay content but increased available P content. Clay and water content of the rewetted samples, especially after oven-drying (KLo) were lower than at initial field capacity (KL), as indication of irreversible properties. In contrast, available P and organic-C content were higher after drying-rewetting processes. Variation of water, clay, organic-C, and available P contents after drying-rewetting processes were significantly affected by respected properties at initial field capacity. These properties tended to change in accordance to Alo+½Feo content. The effect of Alo+½Feo content, however was statisticaly detected only on the water content at KLo (rewetted after oven-dried) and on organic C content at KL2 and KL4 (rewetted after air-dried for 2 and 4 days). Â

Dehydroxylation and Ostwald ripening effects in roofing slates

Roofing slates only open in wet and when they are maintained in wet from quarry. Their irreversible drying could be explained by the closure of porosity following Ostwald ripening processes of illite along the slaty cleavage interface-interphases along with the leaking out water-alkali solutions. Roofing slate drying randomly produces swelling of layers and crystallite coalescence. They have been detected huge deformations of the illite-chlorite XRD 10 A peak by isothermal scanning (i.e., 95°C) of XRD under thermo-photonic stimulation and electronic control of temperature. These large anomalies of the illite crystallinity peak working with aliquots of slate prevent against the petrological use of the Kubler index using the slaty cleavage of micro-mono-blocks. The slate also shows a continuous distribution of thermoluminescence traps with maxima concentration in 300°C, which could be attributed to the creation-annihilation of [AlO 4 /alcali] + y [AlO4]° centres. The convergent trend of thermoluminescence glow curves of preheated aliquots, circa 475°C, coincides with the theoretical maxima of dehydroxylation temperature.

Induration of C Horizons by Allophane and Imogolite in Costa Rican Volcanic Soils

Little is known about the contribution of allophane and imogolite to induration of soil horizons in the perudic tropics. In this study we observed, to a depth of 10 m, indurated sandy C horizons that contained isotropic translucent fine‐textured coatings in Holocene and Pleistocene alluvial andesitic deposits situated in the perudic moisture regime in Costa Rica. The horizons have a firm to extremely firm consistence and do not slake in water. Optical microscopy showed that the coatings cover and bridge primary minerals, forming a three‐dimensional framework in the horizons, which indicates a post‐depositional origin. Bulk chemical analyses show the presence of allophane in the indurated horizons. Scanning electron microscopy (SEM) of undisturbed mineral surfaces confirmed the existence of the coating framework. Chemical analyses, obtained by SEM energy‐dispersive x‐ray, indicate an alumino‐silicate coating with Al/Si ratios ranging from 1.6 to 2.1. Coatings were studied by TEM, carried out on an ultra‐thin section (50 nm) cut from a coating that was in situ sampled by microdrilling in an uncovered thin section. All clay material in the horizons consists of coatings of allophane and imogolite. Rapid weathering of the andesitic parent material released large amounts of Al and Si, which accumulated as amorphous gels due to oversaturation of the soil solution near the wetting front or in deeper water‐conducting layers. We conclude that the mechanisms for soil horizon induration include changes in moisture conditions due to short seasonal drying, climatic changes, tectonic uplifting, and erosion, which lead to irreversible drying of allophane and imogolite.

96/01226 Irreversible drying of carbonaceous fuels such as low-rank coals

96/01226 Irreversible drying of carbonaceous fuels such as low-rank coals

A development of the relation between drying energy savings and thermodynamic irreversibility

A general consistent approach to evaluation of drying energy savings is proposed which is based on the energy (available energy) balance of the arbitra dryer. The concept of the so-called energy saving ability function, s w is introduced, which determines the savings of available energy (related to the unit mass of the moisture evaporated) obtained when the clearly defined drying process is replaced by the optimal one. The importance of the opt process, minimizing the sum of energy and investment costs, as the reference frame for the saving ability function is stressed and the optimization pro for several drying processes with granular solids is outlined. The relation between reduction of the drying irreversibility, increase of energy utiliza efficiency and available energy savings is determined. The optimum of a clearly defined irreversible drying process for the finite time transition of a and a connection between the process time, apparatus price and the optimal process intensity are pointed out. An increase of the possible energy saving to optimization is revealed in the high-rate drying regimes which proves the rationale of the optimization for intensive short-time drying processes. T and quantitative nature of the approach presented here enables its direct application to arbitrary industrial dryers.

Characteristics and significance of some humate-cemented sands (humicretes) at Cape Flattery, Queensland, Australia

SummaryHumate-cemented sands (humicretes) are exposed at several locations along the foreshore and in gullies near Cape Flattery, North Queensland, Australia. Three broad types of humate accumulation are recognized: (a) pedogenetic; (b) groundwater; and (c) aquatic. Pedogenetic and groundwater humicretes usually have a grain-supported fabric in which quartz represents > 99% of the framework grains. Hand specimens of humicrete are brittle but disintegrate rapidly in 0.1 N-NaOH. Concentration of humate is considered to have occurred by vertically and laterally migrating groundwater, while induration has probably been caused by irreversible drying of the humic substances during periods of seasonal water-table lowering. Radiocarbon dating of an in situ root embedded in indurated humate near Cape Flattery has indicated a ‘background’ age of > 48000 C–14 years.

On the variability of amorphous materials in andosols and their relationships to irreversible drying and P-retention

The amorphous components of Andosol samples from Costa Rica, Japan, New Zealand and Rwanda were examined for chemical and mineralogical variability by determining 0.5 N NaOH extractable Si and Al, CEC delta value, content of co-precipitated Si-Al gels (allophane sensu stricto) and by DTA. This analytical information was compared with magnitude of P-retention and the physical property of irreversible drying. The former showed no significant relationship except for a tendency of highly siliceous members of the soils studied to have less P-retention. Irreversible drying appears to be strongly related to presence of discrete phases of Si and Al gels. The agricultural significance of the latter and the need for emphasizing in classification systems the Si/Al ratios of such amorphous materials for differentiating among Andosols have been stressed. A suitable differential solubility test for quantifying amorphous compounds of real significance is still not available.