Improve Soil Physical Properties Research Articles

PENGARUH PUPUK HAYATI DAN TANAMAN JARAK PAGAR (Jatropha curcas L.)TERHADAP PENYERAPAN LOGAM BERAT TEMBAGA (Cu) DAN TIMBAL (Pb) PADA LAHAN BERPASIR

In general, coastal areas have the physical and chemical properties of lessfertile land with an extreme dry climate, so that only a few plants that can live,including Jatropha curcas L. To enhance fertility and improve soil physicalproperties, need the addition of organic fertilizer. Source of compost canbe derived from a variety of wastes, including household waste and landfill.Quality compost landfill taken from Piyungan, Yogyakarta, has a high content of organic C, pH neutral, low N concentration, with the ratio C/N is very high. But compost landfill has an obstacle in the form of heavy metal containing high Cu and Pb. To prevent accumulation heavy metals into plant tissue or clean up heavy metals from the soil it was attempted by phytoremediation using jatropha plantation and bio-fertilizer that contains bacteria Azotobacter sp and Pseudomonas sp.From the research results can be informed that: (1) The city compost and biological fertilizers, can increase soil fertility with increasing nutrient content in soil. (2) Biofertilizers could inhibit the accumulation of copper (Cu) and lead (Pb) into Jatropha curcas L., (3)Jatropha plant can be classified as phytoremediation plants, because it can absorption heavy metals into leaf tissue.Key words: landfill compost , bio fertilizer, jatropha plants, heavy metals

Effects of grazing exclusion in Xilin Gol grassland differ between regions

Establishment of grazing exclusion has become an important rangeland rehabilitation strategy in semi-arid regions. However, the effect of grazing exclusion on soil has been controversial, and the regional differences in these effects have not been investigated sufficiently. Based on field investigation and lab experiments, the present study compared the vegetation cover, vegetation height, biomass, soil organic carbon (SOC), total nitrogen (TN) and available nitrogen (AN) contents inside and outside 18 grazing exclosures that had been established for approximately 10 years in the Xilin Gol grassland. Then, we examined the effect of grazing exclusion on vegetation and soil. We also analyzed the regional differences and the impact factors related to the restoration effects since the Beijing-Tianjin Sandstorm Source Control Project was implemented. Data processing and statistical analyses were carried out with SPSS 13.0. The results showed that the exclosures exhibited significantly (p<0.01) higher values regarding biomass (153.407g/m2), vegetation height (27.417cm) and vegetation cover (62.5%), compared to free grazing lands, where these values were 76.094g/m2, 12.587cm and 45%, respectively. This suggested that exclosures are effective in restoring vegetation. The higher the annual precipitation, the better the effect of grazing exclusion on vegetation will be. The exclosures significantly improved soil physical properties: soil bulk density inside the exclosures (1.382g/cm3) was lower than outside (1.457g/cm3) in the 0–5cm depth, and the proportion of soil clay was higher inside the exclosures (0.504%) than outside (0.411%) in the 0–10cm layer. There were linear declines in the restoration effects for SOC and TN at the 0–10cm depth with annual precipitation, and areas with more precipitation exhibited no significant or even a negative restoration effects. Therefore, the recovery of soil and vegetation showed regional differences. In follow-up management policies, different climate zones should adopt corresponding grassland management practices.

Impact of Dry-injection Cultivation to Maintain Soil Physical Properties for an Ultradwarf Bermudagrass Putting Green

Traditional hollow-tine (HT) aerification programs can cause substantial damage to the putting green surface resulting in prolonged recovery. Despite the growing interest in new and alternative aerification technology, there is a lack of information in the literature comparing new or alternative technology with traditional methods on ultradwarf bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis (Burtt-Davy)] putting greens. Therefore, the objective of this research was to determine the best combination of dry-injection (DI) cultivation technology with modified traditional HT aerification programs to achieve minimal surface disruption without a compromise in soil physical properties. Research was conducted at the Mississippi State University golf course practice putting green from 1 June to 31 Aug. 2014 and 2015. Treatments included two HT sizes (0.6 and 1.3 cm diameter), various DI cultivation frequencies applied with a DryJect 4800, and a noncultivated control. The HT 1.3 cm diameter tine size had 76% greater water infiltration (7.6 cm depth) compared with the DI + HT 0.6 cm diameter tine size treatment. However, DI + HT 0.6 cm diameter tine size had greater water infiltration at the 10.1 cm depth than the noncultivated control. Results suggest a need for an annual HT aerification event due to reduced water infiltration and increased volumetric water content (VWC) in the noncultivated control treatment. It can be concluded that DI would be best used in combination with HT 1.3 or 0.6 cm diameter tine sizes to improve soil physical properties; however, the DI + HT 0.6 cm diameter tine size treatment resulted in minimum surface disruption while still improving soil physical properties compared with the noncultivated control.

Optimal sequestration of carbon dioxide and phosphorus in soils by gypsum amendment

Gypsum has been applied as a natural fertilizer and soil amendment for centuries in agriculture for providing crop nutrients such as Ca and S, and for improving soil physical properties. Recently, gypsum has been tested for sequestrating CO2 from the air and for capturing soluble phosphates in the soil, through formation of insoluble calcium phosphates and carbonates. However, the environmental factors controlling these sequestration processes have not been systemically studied. Here, we calculate optimal conditions of sequestration using chemical equilibrium modeling. Our results show that CO2 carbonation is effective at pH higher than 8.5 at atmospheric concentration. The removal of P is higher than 80 % for pH higher than 6.4, when Ca and P are at stoichiometric ratio. Also, placement of gypsum in subsoil is more effective for CO2 capture than applying it on soil surface since soil pores often contain higher concentrations of CO2 due to the soil respiration process. Overall, increases in medium pH, gypsum application rate, or CO2 partial pressure can increase the effectiveness of the amendment.

English

Excessive tillage in conventional agriculture systems may cause plough pan, which alters soil physical properties, and thus adversely affects the crop growth and productivity. This study was conducted to monitor the effect of different tillage practices in wheat-based cropping systems on soil physical properties, allometry and grain yield of wheat. Wheat was planted in different cropping systems (viz. fallow-wheat, rice-wheat, cotton-wheat, mungbean-wheat and sorghum-wheat with zero tillage, conventional tillage, deep tillage and on two types of beds (60/30 cm with four rows) and (90/45 cm with six rows). Interaction between different tillage practices and cropping systems had significant effect on soil bulk density and total porosity, wheat allometry and grain yield. Minimum bulk density tied with higher total porosity was recorded in both types of bed sowing followed by deep tillage. This improvement in soil physical properties caused improvement in leaf area index and duration, specific leaf area, crop growth, and net assimilation rates. As a result, the productivity of bed sown wheat was better; however, grain yield of zero tilled wheat was low due to poor crop growth and net assimilation rate. Wheat productivity was substantially low when planted after sorghum; nonetheless, and was quite high when sown after mungbean. In crux, wheat planting on beds after mungbean is the best option considering the long-term environmental sustainability of wheat-based cropping systems. © 2016 Friends Science Publishers

Humification degree and its relationship with some soil physical characteristics on robusta coffee (Coffea canephora) plantation

Soil moisture stress in coffee plant impacts on the productivity of coffee fruit at PT. Perkebunan Nusantara XII, it is because the low ability of the soil to store water. The ability of the soil to store water can be increased by increasing the organic matter content of soil, especially humic substances. Soil organic matter plays an important role in the improvement of soil physical properties, especially the availability of soil moisture for plants. The purpose of this study was to analyze several humification parameters at four age of plantations plots of coffee and its relation to the water distribution potensial on Inceptisol PT. Perkebunan Nusantara XII Malang district. The research was conducted at PT. Perkebunan Nusantara XII were taken soil samples from 8, 28, 40, and 80 years old robusta coffee plots at 0-30 cm and 30-60 cm soil depth. The results showed that the increasing the age of the coffee plantations significantly increased the input of organic matter in the soil, with indicators of increased litter on soil surface, increased levels of soil C-organic and N-total, humic acid and soil pH. Increasing age of coffee plantations until 80 years did not affect to the value of humification parameters (C/N ratio, HA/FA ratio, E4/E6 ratio, and the humification rate (HR)). The age of coffee plantations affected the total acidity, carboxylic groups and phenolic OH, where the values tended to decrease with the older of coffee plantations in the 0-30 cm of soil layers and increased in 30-60 cm. Increasing age of coffee plantations improved the total pores and available water content in the 0-30 cm of soil layer.

Utilization of crops residues as compost and biochar for improving soil physical properties and upland rice productivity

The abundance of crops waste in the agricultural field can be converted to organic fertilizer throughout the process of composting or pyrolysis to return back into the soil. The study aimed to elucidate the effect of compost and biochar application on the physical properties and productivity of upland rice at Village of Sukaraja Nuban, Batanghari Nuban Sub district, East Lampung Regency in 2015. The amendment treatments were A. control; B. 10 t rice husk biochar/ ha; C. 10 t maize cob biochar/ha; D. 10 t straw compost/ha; E. 10 t stover compost/ha, F. 10 t rice husk biochar/ha + 10 t straw compost/ha; F. 10 t maize cob biochar/ha + 10 t maize stover compost/ha. The treatments were arranged in randomized block design with four replicates. The plot size for each treatment was 10 x 20 m. After incubation for about one month, undisturbed soil samples were taken using copper ring at 10–20 cm depth for laboratory analyzes. Analyses of soil physical properties included bulk density, particle density, total porosity, drainage porosity, and soil water condition. Plant observations conducted at harvest were plant height, number of panicle, number of grain/panicle, and grain weight/plot. Results of the study showed that biochar and compost improved soil physical properties such as bulk density, total porosity, fast drainage pores, water content, and permeability of soil. The combination of rice husk biochar and straw compost gave better effect than single applications on rice production components (numbers of panicle and grains of rice), and gave the highest yield of 4.875 t/ha. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:Table Normal; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:Calibri,sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;}

Utilization of crops residues as compost and biochar for improving soil physical properties and upland rice productivity

Utilization of crops residues as compost and biochar for improving soil physical properties and upland rice productivity

No tillage and liming reduce greenhouse gas emissions from poorly drained agricultural soils in Mediterranean regions

No tillage (NT) has been associated to increased N2O emission from poorly drained agricultural soils. This is the case for soils with a low permeable Bt horizon, which generates a perched water layer after water addition (via rainfall or irrigation) over a long period of time. Moreover, these soils often have problems of acidity and require liming application to sustain crop productivity; changes in soil pH have large implications for the production and consumption of soil greenhouse gas (GHG) emissions. Here, we assessed in a split-plot design the individual and interactive effects of tillage practices (conventional tillage (CT) vs. NT) and liming (Ca-amendment vs. not-amendment) on N2O and CH4 emissions from poorly drained acidic soils, over a field experiment with a rainfed triticale crop. Soil mineral N concentrations, pH, temperature, moisture, water soluble organic carbon, GHG fluxes and denitrification capacity were measured during the experiment. Tillage increased N2O emissions by 68% compared to NT and generally led to higher CH4 emissions; both effects were due to the higher soil moisture content under CT plots. Under CT, liming reduced N2O emissions by 61% whereas no effect was observed under NT. Under both CT and NT, CH4 oxidation was enhanced after liming application due to decreased Al3+ toxicity. Based on our results, NT should be promoted as a means to improve soil physical properties and concurrently reduce N2O and CH4 emissions. Raising the soil pH via liming has positive effects on crop yield; here we show that it may also serve to mitigate CH4 emissions and, under CT, abate N2O emissions.

Soil physical properties response to grassland conversion from cropland on the semi‐arid area

AbstractSoil physical properties crucially affect vegetation restoration on the semi‐arid Loess Plateau. Understanding how converting cropland into grassland affects soil physical properties is essential throughout a long‐term natural vegetation restoration chronosequence. The objectives of this study were to determine the effects of naturally restored grassland from cropland (wheat) on soil physical properties over time. Hence, we analysed the effects on various soil physical properties at different restoration ages (0, 5, 15 and 30 years). Our results revealed that soil physical properties changed dynamically in response to the land use change over time. Grassland restoration increases soil texture coarseness in the upper soil layer (0–5 cm). After a 15‐year restoration, soil hydraulic conductivity attained the maximum measured value, but in restoration age (to 30 years) did not further improve soil hydraulic conductivity. Restoration increased the field capacity and the soil water content under the restored grassland when compared with the cropland, but increases were not linearly related to the restoration age. Our study suggests that converting cropland into grassland improved the soil structure and soil–water conditions, and that the first 15 years of restoration was sufficient in order to achieve most of the improvements in soil physical properties. Our results will be helpful in providing soil hydraulic parameters to other researchers with the aim of improving the restored grassland to become more effective and sustainable on the semi‐arid area. Copyright © 2016 John Wiley &amp; Sons, Ltd.

Effects of Biochar and Marble mud on Mine Waste Properties to Reclaim Tailing Ponds

AbstractThe effects of biochar addition in improving soil physical properties are not clearly understood in mining tailings. The objective of this study was to determine the effects of three different types of biochars, in addition to marble mud (MM) and their mixtures, on the structural stability and water retention of mine wastes in Cartagena, Spain. Biochars were produced at 500 °C from pig manure (PM), cotton (Gossipium hirsutum L.) crop residues (CR) and municipal solid waste (MSW). Biochars were added to the mine waste (MW) along with MM and a control (no amendments added). These mixtures were incubated in cores for 90 days (25 °C). PM and CR mixed with MM decreased soil bulk density (from 0 · 98 g cm‐3 to 0 · 89 and 0 · 84 g cm−3, respectively). Amendments had no significant effect on total porosity whereas they increased gas diffusion by 100%, except for MSW. MM improved the plant available water from 0 · 59 to 2 · 56 cm as its combination with biochars, extremely relevant in water scarce climates. The micropores were likely replaced by mesopores when application of PM, CR, MM, and biochars + MM and they improved water retention. Total carbon (TC) and total nitrogen (TN) increased by using biochars and MM and no significant effects were assessed on aggregates. In general, MM mixed with PM and CR derived biochar improved the structural stability and exhibited a strong impact in reclaiming physical quality on mine tailings. Copyright © 2016 John Wiley &amp; Sons, Ltd.

Narrowing the Agronomic Yield Gaps of Maize by Improved Soil, Cultivar, and Agricultural Management Practices in Different Climate Zones of Northeast China

Abstract Northeast China (NEC) is one of the major agricultural production areas in China, producing about 30% of China’s total maize output. In the past five decades, maize yields in NEC increased rapidly. However, farmer yields still have potential to be increased. Therefore, it is important to quantify the impacts of agronomic factors, including soil physical properties, cultivar selections, and management practices on yield gaps of maize under the changing climate in NEC in order to provide reliable recommendations to narrow down the yield gaps. In this study, the Agricultural Production Systems Simulator (APSIM)-Maize model was used to separate the contributions of soil physical properties, cultivar selections, and management practices to maize yield gaps. The results indicate that approximately 5%, 12%, and 18% of potential yield loss of maize is attributable to soil physical properties, cultivar selection, and management practices. Simulation analyses showed that potential ascensions of yield of maize by improving soil physical properties PAYs, changing to cultivar with longer maturity PAYc, and improving management practices PAYm for the entire region were 0.6, 1.5, and 2.2 ton ha−1 or 9%, 23%, and 34% increases, respectively, in NEC. In addition, PAYc and PAYm varied considerably from location to location (0.4 to 2.2 and 0.9 to 4.5 ton ha−1 respectively), which may be associated with the spatial variation of growing season temperature and precipitation among climate zones in NEC. Therefore, changing to cultivars with longer growing season requirement and improving management practices are the top strategies for improving yield of maize in NEC, especially for the north and west areas.

KENTSEL ARITMA ÇAMURUNUN TARIMSAL KULLANIMI

According to experimental results, there has been valuable data that sludge applications to soil has increased soil fertility and improved soil physical properties. On the other hand, undesired heavy metal accumulation has occurred by sludge applications, but this accumulation levels has not yet been determined above the food and fodder norms. It is stated that as long as the agricultural use of sludge in the production of crops for human consumption follows current regulations and guidelines, it present a manageable risks on crop production, environment and consumers. Before soils reach regulatory limit of chemical pollutant loading by sludge applications, additional information will be needed to asses potential long term impacts of sludge on ground water quality and on the sustainability of soils for crop production. It is thought that in the state of having more alternative organic matter source alternatives, application of treatment sludge in plant growing areas except for food crop production is a more safely alternative disposal; also educational programs for sludge utilization should be organized.

Effect of chemical and organic fertilization on soil carbon and nitrogen accumulation in a newly cultivated farmland

Increased food demand from the rapidly growing human population has caused intensive land transition from desert to farmland in arid regions of northwest China. In this developing ecosystem, the optimized fertilization strategies are becoming an urgent need for sustainable crop productivity, efficient resources use, together with the delivery of ecosystems services including soil carbon (C) and nitrogen (N) accumulation. Through a 7-year field experiment with 9 fertilization treatments in a newly cultivated farmland, we tested whether different fertilizations had significant influences on soil C and N accumulation in this developing ecosystem, and also investigated possible mechanisms for this influence. The results showed that applying organic manure in cultivated farmland significantly increased the soil C and N accumulation rates; this influence was greater when it was combined with chemical fertilizer, accumulating 2.01 t C and 0.11 t N ha–1 yr–1 in the most successful fertilization treatment. These high rates of C and N accumulation were found associated with increased input of C and N, although the relationship between the N accumulation rate and N input was not significant. The improved soil physical properties was observed under only organic manure and integrated fertilization treatments, and the significant relationship between soil C or N and soil physical properties were also found in this study. The results suggest that in newly cultivated farmland, long term organic manure and integrated fertilization can yield significant benefits for soil C and N accumulation, and deliver additional influence on physical properties.

Research progress on wind erosion control with polyacrylamide (PAM).

Soil wind erosion is one of the main reasons for soil degradation in the northwest region of China. Polyacrylamide (PAM), as an efficient soil amendment, has gained extensive attention in recent years since it is effective in improving the structure of surface soil due to its special physical and chemical properties. This paper introduced the physical and chemical properties of PAM, reviewed the effects of PAM on soil wind erosion amount and threshold wind velocity, as well as the effect differences of PAM in soil wind erosion control under conditions of various methods and doses. Its effect was proved by comparing with other materials in detail. Furthermore, we analyzed the mecha-nism of wind erosion control with PAM according to its influence on soil physical characteristics. Comprehensive analysis showed that, although some problems existed in wind erosion control with (PAM), PAM as a sand fixation agent, can not only enhance the capacity of the soil resis-tance to wind erosion, but also improve soil physical properties to form better soil conditions. Besides, we proposed that combination of PAM and plant growth would increase the survival rate of plants greatly, control soil wind erosion in wind-erosive areas, and improve the quality of the ecological environment construction. Thus, PAM has practically important significance and wide application prospect in controlling soil wind erosion.

Acidic sandy soil improvement with biochar — A microcosm study

Biochar produced from a wide range of organic materials by pyrolysis has been reported as a means to improve soil physical properties, fertility and crop productivity. However, there is a lack of studies on the complex effects of biochar both on the degraded sandy soil physico-chemical properties and the soil biota as well as on toxicity, particularly in combined application with fertilizer and compost.A 7-week microcosm experiment was conducted to improve the quality of an acidic sandy soil combining variations in biochar types and amounts, compost and fertilizer application rates. The applied biochars were produced from different feedstocks such as grain husks, paper fibre sludge and wood screenings. The main purpose of the microcosm experiment was to assess the efficiency and applicability of different biochars as soil amendment prior to field trials and to choose the most efficient biochar to improve the fertility, biological activity and physical properties of acidic sandy soils. We complemented the methodology with ecotoxicity assessment to evaluate the possible risks to the soil as habitat for microbes, plants and animals.There was clear evidence of biochar-soil interactions positively affecting both the physico-chemical properties of the tested acidic sandy soil and the soil biota.Our results suggest that the grain husk and the paper fibre sludge biochars applied to the tested soil at 1% and 0.5 w/w% rate mixed with compost, respectively can supply a more liveable habitat for plants and soil living animals than the acidic sandy soil without treatment.

Effect of Inorganic Fertilizers and Farm Yard Manure on Physical Properties of Soil Under Rice-Wheat Cropping

In rice-wheat cropping, puddling of field in standing water damages soil structure and affects soil physical properties. Application of inorganic fertilizer and organic manure stimulates crop biomass and amount of residue returned into soil after crop harvest, and may improve soil physical properties. Therefore, a field experiment was conducted for 5 years at Regional station, Gurdaspur to assess the effect of inorganic fertilizers and farmyard manure (FYM) applied either alone or conjointly on physical properties of soil under rice-wheat cropping system. Soil fertility management treatments consisted of unfertilized control, NPK, FYM, N+FYM and NPK+FYM. Soil porosity increased significantly (p<0.05), while bulk density (Db) decreased with the application of NPK and FYM. The effect was however, more pronounced when applied conjointly. Final infiltration rate also increased significantly with the application of NPK and FYM either alone or conjointly, although the effect was greater when applied conjointly. Saturated hydraulic conductivity (Ks), on the other hand was significantly higher with FYM, compared with NPK alone application. Application of FYM either alone or conjointly with inorganic fertilizers (N+FYM/NPK+FYM) did not significantly influenced Ks. Soil moisture retention at field capacity (FC) and permanent wilting point (PWP) increased significantly with NPK+FYM application. Our results showed that conjoint application of inorganic fertilizers and organic manure improved physical properties of soil under ricewheat cropping system.

Improved Soil Physical Properties, Yield and Water Productivity under Controlled Traffic, Raised-Bed Farming

Improved Soil Physical Properties, Yield and Water Productivity under Controlled Traffic, Raised-Bed Farming

EFFECT OF FLY ASH ON CROP YIELD AND PHYSICO-CHEMICAL, MICROBIAL AND ENZYME ACTIVITIES OF SODIC SOILS

Safe utilization of fly ash (FA) and reclamation of sodic soils are important environmental problems. In this study a field experiment was carried out with Vigna radiata L. crop using fly ash (FA) and phosphogypsum (PGY) as amendments in sodic soil during 2011 at Lucknow, Uttar Pradesh, India. V. radiata L. was sown in sodic soil amended with press mud (10 t ha-1) considered as control. Besides, 10 and 20 t ha-1 doses of FA and PGY were considered as other four treatments, respectively. The growth variables such as survival, root-shoot length, biomass production, number of pods and nodules were significantly higher in soil treated with 20 t ha-1 FA. Physico-chemical, biological and biochemical properties were analysed at the time of harvest. Our results showed that FA improves soil physical properties to a greater extent in comparison to PGY. However, pH and electrical conductivity showed adverse pattern, but soil organic carbon, nitrogen, microbial biomass (MB) and population of bacteria and earthworms were highest in the soils amended with 20 t ha-1 FA. The population of fungi was unaffected through these treatments. The variations in dehydrogenase, alkaline phosphatase and -glucosidase were significant amongst the treatments and showed enzyme specific trends. The study suggests that FA had positive effect on crop growth as well as physicochemical, microbial and enzymatic activities. Therefore, FA in combination with press mud can be used for an efficient reclamation of sodic soils.

Hydro-Physical Properties of a Typic Hapludult under the Effect of Rice Husk Ash

The combustion of rice husk generates a partially burnt mixture called rice husk ash (RHA) that can be used as a source of nutrients to crops and as a conditioner of soil physical properties. The objective of this study was to evaluate the effect of RHA levels on the hydro-physical properties of a Typic Hapludult. The experimental design was composed of random blocks with four replications, which comprised plots of 24 m2 and treatments with increasing RHA rates: 0, 40, 80 and 120 Mg ha-1. Undisturbed soil samples were collected in the soil layers of 0.00-0.10 and 0.10-0.20 m after nine months of RHA application, using steel cylinders (0.03 m of height and 0.047 m of diameter). These samples were used to determine soil bulk density (Bd), total soil porosity (TP), soil macroporosity (Ma), soil microporosity (Mi) and the available water capacity (AWC). Disturbed soil samples were collected to determine the stability of soil aggregates in water, mean weight diameter of water stable aggregates (MWD), and soil particle size distribution. The results show that, as the RHA rate increased in the soil, Bd values decreased and TP, Ma and MWD values increased. No effect of RHA was found on Mi and AWC values. The effects of RHA on the S parameter (Dexter, 2004), precompression stress and compression index (Dias Junior and Pierce, 1995) values are consistent those shown for density and total porosity. Rice husk ash was shown to be an efficient residue to improve soil physical properties, mainly at rates between 40 and 80 Mg ha-1. Rice husk ash reduces bulk density and increases total porosity, macroporosity and soil aggregation, but does not affect microporosity, field capacity, permanent wilting point, and available water capacity of the soil. The effect of rice husk ash on the S parameter, precompression stress and index compressibility coefficient values are consistent with those observed for the bulk density and total porosity.