Potential Soil Amendment Research Articles

Improved methane production of corn straw by the stimulation of calcium peroxide

This research focused on the effect of calcium peroxide (CaO2) addition on anaerobic digestion (AD) of corn straw. It was found that the CaO2 dose of 0.032–0.256 g·g−1 TVS (total VS of substrate and inoculum) had positive effect on the AD of corn straw by improving methane yield and content in biogas. Maximum methane yield was achieved at the CaO2 dose of 0.032 g·g−1 TVS, which was 241.6 mL·g−1 VSS (VS of substrate) and 11% higher than that of the control. Methane content in biogas also increased according to the in situ immobilization of CO2 by Ca(OH)2 that produced via the reaction of CaO2 with water (XRD analysis results). Microbial community structure was significantly affected by CaO2 addition. The variation of bacterial community structure led to higher hydrolysis rate, and the variation of archaea community structure ensured the proceeding of methanogenesis process. The use of CaO2 could be a cost-effective method to improve methane production of corn straw because it avoids harsh condition and high cost (e.g., chemical and energy inputs) associated with conventional chemical treatment techniques. The digestate from the AD with the addition of CaO2 can contain high CaCO3 content, making it a potential soil amendment for acidic soil.

Pyrolysis treatment of sewage sludge: A promising way to produce phosphorus fertilizer

Direct use of sewage sludge for application in agriculture is frequently discouraged with reference to toxic compounds. Therefore, methods for sewage sludge conversion and modification to decrease heavy metals mobility are required. Our study was conducted to assess and compare municipal and industrial sewage sludge for the production of carbonaceous pyrolysis products as a potential soil amendment with high phosphorus content. For carbonization at 430 °C a lab-pyrolysis reactor was used. The feedstocks and pyrolysis products were characterized (pH, electrical conductivity, FTIR, SEM, CHNS elemental composition, polycyclic aromatic hydrocarbons (PAH) and toxic metal concentration). The obtained results explored the possibility of sewage sludge conversion by pyrolysis process to stable and valuable products with a 2- to 3-fold increase of phosphorus content. Using DTPA extraction protocol we confirmed the good stability of toxic metals in both sewage sludge pyrolysis products compared to feedstocks. The incorporation of pyrolysis products into P-deficient and toxic metal polluted soil was effective to reduce pollutant mobility and to add available phosphorus. Our characterization study highlighted the potential of pyrolysis for closure of the phosphorus cycle and for the production of fertilizers from complex materials such as sewage sludge.

Comparative effects of biochar-nanosheets and conventional organic-amendments on health risks abatement of potentially toxic elements via consumption of wheat grown on industrially contaminated-soil

Potentially toxic elements (PTEs) discharge to the soil environment through increased anthropogenic activities is a global threat. These PTEs can have harmful and chronic-persistent health effects on exposed populations through food consumption grown on contaminated soils. Efforts to investigate the transformation mechanism and accumulation behavior of PTEs in soil-plant system and their adverse health-effects have focused extensively in previous studies. However, limited studies address biochar nanosheets (BCNs) as a potential soil amendment to reduced humans health risks through dietary intake of food-crop grown on PTE-contaminated soil. Here, we showed how BCNs cutback health hazards of PTEs through impacts on bioavailability and phytoaccumulation of PTEs, and their daily intake via consumption of wheat. When BCNs amendment was compared with both conventional organic amendments (COAs) and control, it significantly (P ≤ 0.05) reduced bioavailability and uptake of PTEs by wheat plants. Based on risk assessment results, the hazard indices (HIs) for PTEs in all treatments were <1, however, BCNs addition significantly (P ≤ 0.05) reduced risk level, when compared to control. Furthermore, the cancer risks for Cd, Cr and Ni over a lifetime of exposure were higher in all treatments than the tolerable limit (1.00E-4 to 1.00E-6), however BCNs addition significantly suppressed cancer risk compared to control. Conclusively, our results suggest that BCNs can be used as soil amendment to reduce potential risks of PTEs through consumption of food grown in PTE-contaminated soils.

Biochar Increased Plant Growth-Promoting Hormones and Helped to Alleviates Salt Stress in Common Bean Seedlings

Salinity seriously disrupts the growth and physiology of plants, whereas phytohormones play an important role in regulating plant responses to salinity stress. Biochar is attracting increasing attention in recent years as a potential soil amendment under stress condition. This study addressed the use of biochar to mitigate salt-stressed soil and evaluated the levels of some phytohormones in bean (Phaseolus vulgaris L.) seedlings. A pot experiment was conducted in a climate-controlled greenhouse with three biochar ratios (control, 10, and 20% mass), three salt stress treatments (non-saline, 6, 12 dS m−1 NaCl), and four replications. The results indicated that sodium (Na) concentration, polyamine oxidase (PAO) activity, the contents of polyamines (putrescine, spermidine, and spermine), abscisic acid (ABA), 1-aminocyclopropane-1-carboxylic acid (ACC), jasmonic acid (JA), and salicylic acid (SA) in bean leaf and root increased under salt stress. However, endogenous indole-3-acetic acid (IAA) content was decreased by salinity compared to the non-saline treatment. On the other hand, we observed decreases of Na concentration, PAO activity, polyamines, ABA, ACC, and JA contents in plants treated by biochar. In contrast, biochar enhanced IAA content and the growth of roots and shoots. As a result, the effectiveness of 20% biochar was superior to the 10% treatment in terms of polyamine contents, especially under saline conditions. Interestingly, there were no considerable changes in phytohormone contents by use of biochar under non-saline conditions. Overall, biochar alleviated the negative effects of salt stress on bean seedlings by reduction of Na concentration, endogenous stress hormones, and improvement of growth hormones.

Effects of Paddy Husk Biochar on Selected Physical and Chemical Properties of the Low Humic Gley Soil in the Low Country Wet Zone

Biochar made by pyrolysis of various types of biomass has been recognized in recent years as a potential soil amendment. Studies from different parts of the world using a variety of feedstock materials, process conditions and applications in different soil types have reported a diverse range of effects that are sometimes conflicting. Though paddy husk biochar (Kara dahayya) has been used in Sri Lankan paddy fields since ancient times, the actual outcome of this is uncertain owing to the limited number of research that have been carried out. This study focused on studying the effects of paddy husk biochar made by traditional methods, with and without other soil amendments such as compost, mineral fertilizers and their combinations on selected physical and chemical properties of Low Humic Gley soil used for paddy cultivation in the Low Country Wet Zone. A pot experiment was carried out from May to August 2015 with six treatments, namely; T1-Soil only (Control), T2-Soil+Paddy husk biochar, T3-Soil+Compost, T4-Soil+NPK(mineral fertilizer), T5- Soil+Compost+Paddy husk biochar and T6-Soil+NPK+Paddy husk biochar with four replicates for each treatment. The physical properties of soil were analyzed initially as well as at the end of the experiment, while soil chemical properties were analyzed once every 3 weeks during the study period. The results revealed that paddy husk biochar used in this experiment serve as both a soil fertilizer and as a soil conditioner in the test soil. Principal Component Analysis (PCA) revealed that the application of paddy husk biochar along with mineral fertilizer (T6) is the most effective treatment for this soil. This treatment recorded the highest porosity of 60.26% and the second lowest bulk density of 1.10 g/cm3. Also increasing trends in soil pH, organic carbon, total nitrogen and cation exchange capacity were observed in this treatment. Based on these results, it can be concluded that the application of paddy husk biochar along with recommended levels of mineral fertilizer is effective in improving certain properties of Low Humic Gley soil of the Low Country Wet Zone. Keywords: Paddy husk biochar, Low humic gley soil, Paddy cultivation, Soil physical and chemical properties, Soil amendments

Biochar and Soil Physical Properties

Core Ideas Biochar generally improves the soil physical environment Sandy soils appear to respond more to biochar than clayey soils Long-term studies are needed to conclusively discern the extent of biochar effects Biochar is considered to be a potential soil amendment. However, its implications for soil physical and hydraulic properties have not been widely discussed. Changes in the soil physical environment influence the numerous services that soils provide. This paper (i) reviewed the impacts of biochar on soil compaction, mechanical, structural, hydraulic, and thermal properties; (ii) discussed factors affecting biochar performance; and (iii) identified research areas. Biochar generally reduces soil bulk density by 3 to 31%, increases porosity by 14 to 64%, and has limited or no effects on penetration resistance. Biochar increases wet aggregate stability by 3 to 226%, improves soil consistency, and has mixed effects on dry soil aggregate stability. It increases available water by 4 to 130%. Saturated hydraulic conductivity decreases in coarse-textured soils, and increases in fine-textured soils following biochar application. Studies on other properties are few but suggest that biochar reduces tensile strength and particle density, alters water infiltration, moderates soil thermal properties, and has minimal effect on soil water repellency. Sandy soils appear to respond more to biochar than clayey soils. Biochar effectiveness increases as the amount of biochar applied increases. A decrease in biochar particle size can increase water retention but may reduce saturated flow. Field-scale and long-term studies assessing all soil physical properties under different scenarios of biochar management are needed. Overall, biochar generally improves the soil physical environment, but long-term field studies are lacking to conclusively ascertain the extent of biochar effects.

Sulfur-enriched biochar as a potential soil amendment and fertiliser

Hydrogen sulfide (H2S) is a highly toxic and corrosive contaminant gas co-generated during anaerobic digestion. Studies have shown that biochars have the potential to adsorb H2S and to promote its oxidisation. To date, no studies have investigated the bioavailabilty to plants of the sulfur (S) contained in biochar when used as an S fertiliser. Biochar was packed into the biogas emissions stream to adsorb the H2S being generated. The resulting sulfur-enriched biochar (SulfaChar) and synthetic S fertiliser (control treatment) were amended to potting soils and the growth response of corn (Zea mays L.) and soybeans [Glycine max (L.) Merr.] and nutrient uptake were measured after a 90-day greenhouse study. SulfaChar contained 36.5% S (S element and SO42–), confirming it adsorbed significant amounts of H2S. Compared with the control treatment, SulfaChar amendment significantly increased corn plant biomass, ranging from 31% to 49% but only a slight increase in soybean biomass (4 to 14%). SulfaChar also increased corn plant uptake of S and other macro- (N, P, K, Ca, and Mg) and micro-nutrients (Zn, Mn and B). Our results show that SulfaChar was a source of plant available S, suggesting that SulfaChar is either a supplier of these nutrients or that it promoted their uptake.

Characterization of bio-oil and its sub-fractions from pyrolysis of Scenedesmus dimorphus

In the present study, microalgae Scenedesmus dimorphus was reported for pyrolysis in a fixed-bed reactor to determine the effects of temperature on products yield and the chemical compositions of the liquid and solid products. Experiments were carried out at a temperature range of 300–600 °C with heating rate of 40 °C/min and nitrogen flow rate of 100 ml/min. The yield of bio-oil was found to be maximum (39.6%) at the temperature of 500 °C and was further fractionated into n-hexane, toluene, ethyl acetate and methanol sub-fractions by using liquid column chromatography. Various characteristics of bio-oil and its sub-fractions were determined by 1H NMR, FTIR and GC–MS. The biochar produced as a co-product can be a potential soil amendment with multiple benefits including soil fertility and C-sequestration. The present investigation suggests the suitability of Scenedesmus dimorphus as a potential feedstock for exploitation of energy and biomaterials through pyrolytic conversion.

Co-production of biochar, bio-oil and syngas from halophyte grass (Achnatherum splendens L.) under three different pyrolysis temperatures

In the present study, pyrolysis of Achnatherum splendens L. was performed under three different pyrolysis temperature (300, 500, and 700°C) to investigate the characteristics of biochar, bio-oil, and syngas. Biochar yield decreased from 48% to 24%, whereas syngas yield increased from 34% to 54% when pyrolysis temperature was increased from 300 to 700°C. Maximum bio-oil yield (27%) was obtained at 500°C. The biochar were characterized for elemental composition, surface, and adsorption properties. The results showed that obtained biochar could be used as a potential soil amendment. The bio-oil and syngas co-products will be evaluated in the future as bioenergy sources. Overall, our results suggests that A. splendens L. could be utilized as a potential feedstock for biochar and bioenergy production through pyrolytic route.

Feather hydrolysate from Streptomyces sampsonii GS 1322: A potential low cost soil amendment

Process parameters for obtaining hydrolysate from hen feathers, i.e., initial pH (5.0-9.0) and incubation period (1-6 day), were set and studied, using Streptomyces sampsonii GS 1322 in submerged and solid state conditions. Under submerged conditions, complete hydrolysis of feathers was observed on fifth day [initial pH 8.0, 28±2°C, shaking (150rpm)] with release of soluble protein (2985μgml(-1)) and amino acids (2407μgml(-1)). Cell free hydrolysate showed hydrolysis of casein (18mm), gelatin (26mm), collagen (31mm), hemoglobin (23mm) and Tween 80 (35mm) while 445U keratinase activity. Total soluble protein reached 5mgml(-1) in solid state conditions. During Pot experimentation using barren agriculture soil the effect of feather hydrolysate on wheat crop were recorded. Significant increase (p<0.01) in wheat seed germination was observed in treated soils as compared to untreated. Treatment significantly increased plant height from 30 to 60 days and 30-90 days (p<0.001). Treated soil showed an increase in total microbial count, proteolytic activity, phosphate solubilizing bacteria and ammonifying bacteria, whereas pathogenic fungi load was reduced. S.sampsonii GS 1322 can be used for bio-processing of poultry wastes yielding feather hydrolysate rich in proteins and amino acids for development of low-cost organic amendment to accelerate wheat crop growth in barren agricultural land.

Impact of soybean stover- and pine needle-derived biochars on Pb and As mobility, microbial community, and carbon stability in a contaminated agricultural soil

Biochar is gaining attention as a potential soil amendment to remediate and revitalize the contaminated soils. Simultaneous effects of biochar on metals mobility, microbial abundance, bacterial diversity and carbon storage in soil are scarcely addressed. This study assessed the effect of biochars on metal mobility, microbial abundance, bacterial community, and carbon storage in an agricultural soil contaminated with heavy metals. Biochars derived from soybean stover at 300 and 700 °C (S-BC300 and S-BC700, respectively) and pine needles at the same temperatures (P-BC300 and P-BC700, respectively) were used. A maximum reduction of Pb mobility by 95% was observed from a soil treated with S-BC700, associated with precipitation of chloropyromorphite and hydroxylpyromorphite. In contrast, As was desorbed from soil particles because of P competition. The abundance of Gram-positive and negative bacteria, fungi, actinomycetes, and arbuscular mycorrhizal fungi increased in the soils treated with biochar produced at 300 °C, possibly due to the high dissolved organic and active organic carbons. Microbial abundance in the soils treated with S-BC700 and P-BC700 was constant due to the existence of fixed or non-labile carbon. Changes to bacterial communities in the biochar-treated soils depended on feedstock type and pyrolysis temperature. Actinobacteria substantially increased whereas Acidobacteria and Chloroflexi decreased in the biochar-treated soils. The non-labile carbon fraction was ∼25 fold higher in the biochar-treated soil than the control soil, indicating long-term carbon storage.

Use of amendments in a peat soil to reduce phosphorus losses from forestry operations

Forestry harvesting on peats is known to result in significant losses of soil phosphorus (P) to adjacent waters, and the issue is becoming an increasingly serious concern as peatland forest stocks mature and reach harvestable age. One potential solution could be the use of low-cost P recovery techniques based on the chemical precipitation and/or adsorption of the dissolved fraction of soil P, which would otherwise be lost. Such recovery techniques have shown promise in similar applications on mineral soils. However, the interaction of peat with P adsorbing materials can significantly alter their adsorptive characteristics, and it is consequentially not known what materials might be suitable for this application. This study compared the performance of six potential soil amendments (aluminum water treatment residual (Al-WTR), crushed concrete, gypsum, magnesium hydroxide, magnesium oxide, and steel wool) in removing P from aqueous solution in the presence of a typical forest peat soil. Comparison of adsorption isotherms plotted from these batch adsorption studies showed that the observed P adsorption maxima of Al-WTR and steel wool were increased by the presence of peat, from 10.6mgg−1 and 20.4mgg−1, to 11.8mgg−1 and 52.5mgg−1, respectively. In contrast, the observed P adsorption maxima of crushed concrete, gypsum, and magnesium oxide were reduced in the presence of peat, by 44%, 87%, and 37%, respectively. The maximum P adsorption achieved by magnesium hydroxide was increased from 29.8mgg−1 to 59mgg−1 at an amendment to peat–solid ratio of 1:4, but decreased from 73.9mgg−1 to 23.6mgg−1 at an amendment to peat–solid ratio of 1:10. It was concluded that Al-WTR, in particular, shows considerable promise for use as a soil amendment for P immobilization in a peat environment.

Potential of soil amendments (Biochar and Gypsum) in increasing water use efficiency of Abelmoschus esculentus L. Moench.

Water being an essential component for plant growth and development, its scarcity poses serious threat to crops around the world. Climate changes and global warming are increasing the temperature of earth hence becoming an ultimate cause of water scarcity. It is need of the day to use potential soil amendments that could increase the plants’ resistance under such situations. Biochar and gypsum were used in the present study to improve the water use efficiency (WUE) and growth of Abelmoschus esculentus L. Moench (Lady’s Finger). A 6 weeks experiment was conducted under greenhouse conditions. Stress treatments were applied after 30 days of sowing. Plant height, leaf area, photosynthesis, transpiration rate (Tr), stomatal conductance and WUE were determined weekly under stressed [60% field capacity (F.C.)] and non-stressed (100% F.C.) conditions. Stomatal conductance and Tr decreased and reached near to zero in stressed plants. Stressed plants also showed resistance to water stress upto 5 weeks and gradually perished at sixth week. On the other hand, WUE improved in stressed plants containing biochar and gypsum as compared to untreated plants. Biochar alone is a better strategy to promote plant growth and WUE specifically of A. esculentus, compared to its application in combination with gypsum.

Birch (Betula spp.) wood biochar is a potential soil amendment to reduce glyphosate leaching in agricultural soils

Glyphosate (N-(phosphonomethyl) glycine), a commonly used herbicide in agriculture can leach to deeper soil layers and settle in surface- and ground waters. To mitigate the leaching of pesticides and nutrients, biochar has been suggested as a potential soil amendment due to its ability to sorb both organic and inorganic substances. However, the efficiency of biochar in retaining agro-chemicals in the soil is likely to vary with feedstock material and pyrolysis conditions. A greenhouse pot experiment, mimicking a crop rotation cycle of three plant genera, was established to study the effects of pyrolysis temperature on the ability of birch (Betula sp.) wood originated biochar to reduce the leaching of (i) glyphosate, (ii) its primary degradation product AMPA and (iii) phosphorus from the soil. The biochar types used were produced at three different temperatures: 300 °C (BC300), 375 °C (BC375) and 475 °C (BC475).Compared to the control treatment without biochar, the leaching of glyphosate was reduced by 81%, 74% and 58% in BC300, BC375 and BC475 treated soils, respectively. The respective values for AMPA were 46%, 39% and 23%. Biochar had no significant effect on the retention of water-soluble phosphorus in the soil. Our results corroborate earlier findings on pesticides, suggesting that biochar amendment to the soil is a promising way to reduce also the leaching of glyphosate. Importantly, the ability of biochar to adsorb agro-chemicals depends on the temperature at which feedstock is pyrolysed.

Soil amendments for heavy metals removal from stormwater runoff discharging to environmentally sensitive areas

Summary Concentrations of dissolved metals in stormwater runoff from urbanized watersheds are much higher than established guidelines for the protection of aquatic life. Five potential soil amendment materials derived from affordable, abundant sources have been tested as filter media using shaker tests and were found to remove dissolved metals in stormwater runoff. Blast furnace (BF) slag and basic oxygenated furnace (BOF) slag from a steel mill, a drinking water treatment residual (DWTR) from a surface water treatment plant, goethite-rich overburden (IRON) from a coal mine, and woodchips (WC) were tested. The IRON and BOF amendments were shown to remove 46–98% of dissolved metals (Cr, Co, Cu, Pb, Ni, Zn) in repacked soil columns. Freundlich adsorption isotherm constants for six metals across five materials were calculated. Breakthrough curves of dissolved metals and total metal accumulation within the filter media were measured in column tests using synthetic runoff. A reduction in system performance over time occurred due to progressive saturation of the treatment media. Despite this, the top 7 cm of each filter media removed up to 72% of the dissolved metals. A calibrated HYDRUS-1D model was used to simulate long-term metal accumulation in the filter media, and model results suggest that for these metals a BOF filter media thickness as low as 15 cm can be used to improve stormwater quality to meet standards for up to twenty years. The treatment media evaluated in this research can be used to improve urban stormwater runoff discharging to environmentally sensitive areas (ESAs).

Effect of dried olive pomace – derived biochar on the mobility of cadmium and nickel in soil

This study aims to evaluate dried olive pomace derived biochar as a potential soil amendment for cadmium and nickel immobilization. Biochar was produced through pyrolysis under oxygen-limited conditions, at 400°C (BC400) and 700°C (BC700). Batch sorption/desorption experiments were conducted, investigating different agitation times (30–1440min), initial metal concentration in the solution (100–3000μM) and desorption pH (2–7). Results showed that by amending soil with biochar at increasing rates, enhanced sorption and decreased desorption of both metals were observed. In fact, biochar addition resulted in increased soil pH, possibly enhancing not only metal adsorption on soil surfaces (minerals or oxides), but also metal precipitation. Modeling results concerning sorption equilibrium corroborated this statement. Amended samples showed higher metal retention even at low pH values. Both biochars enhanced the ability of soil to immobilize cadmium and nickel, however in most cases BC700 was proven to be more efficient.

English

The search for suitable alternatives to loam, manure and sand based growing media in Ghana has generated a substantial body of literature on potential amendments akin to the peat based media in developed countries. The objectives of this study were to review literature on potential soil amendments in Ghana, determine the reasons for farmer choice of amendments and determine factors influencing farmer adoption of these amendments. Document review and survey were the main methods used in data collection. The review of literature indicates that the research and discourse on soil amendment over the last two decades have largely been limited to land management and nutrient recovery from waste. Although these have largely been reported as successful, they have not addressed the quality issues of soil amendments as finished product for application in specific production systems. As the amendments are not standardized, farmers adopt varying application rates based on their own experiences. Barriers in the use of amendments were found to be the technology to collect, funds to purchase and labour employment. The agro-ecology and the farmers&rsquo; level of education largely determined the use of particular amendment. The study found wide scale acceptance and adoption of sawdust based poultry litter by urban vegetable farmers, hence the co-composting of sawdust and poultry manure would be the best option that can be developed and standardised for application in urban horticulture. Future research in soil amendment should therefore focus on net N mineralisation, stability indices and the responses of vegetable and ornamental plants to different ratios of co-composting of sawdust and poultry manure. &nbsp; Key words: Growing media, soil amendment, urban horticulture, composting, organic waste, urban farmers. &nbsp

Perennial grass (Arundo donax L.) as a feedstock for thermo-chemical conversion to energy and materials

In the present study, perennial grass species Arundo donax L. was pyrolysed in a fixed-bed reactor and characterization was performed for the liquid and the solid products. The effect of process parameters such as temperature (350–650°C), heating rate (10°C and 40°Cmin−1) and sweeping gas flow rate (50–250mlmin−1) was also investigated. Maximum bio-oil yield of ∼26% was observed at 500°C for the heating rate of 40°Cmin−1. Chemical composition of the bio-oil was analysed through NMR, FTIR and GC–MS. The biochar was characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR) spectroscopy along with elemental analysis (CHN). The biochar produced as a co-product of A. donax pyrolysis can be a potential soil amendment with multiple benefits including increased soil fertility and C-sequestration. Current investigation suggests suitability of A. donax as a potential feedstock for exploitation of energy and biomaterials through pyrolytic route.

ENHANCING COPPER AND LEAD BIOACCUMULATION IN RAPESEED BY ADDING HEMP SHIVES AS SOIL NATURAL AMENDMENTS

The current study reveals the results of a phytoremediation process applied to a multi metal contaminated soil, located in close proximity to an energy power plant. Phytoremediation process was studied using the rapeseed cultivation, both in the presence and absence of hemp shives, considered as potential natural soil amendments. The physiological responses of the rapeseed plants, such as variations in length and accumulation of biomass, as well as the content of assimilating pigments were investigated. The concentrations of Cu (II) and Pb (II) ions have also been determined in soil and plants aiming at locating the metal ions in different organs of the plants. By using hemp shives as amendments, bioaccumulation of copper and lead ions in plant increases. The plants cultivated in the presence of high amounts of heavy metal ions have been characterized by an inhibition of growth and development that consisted in decrease of root and stem lengths, as well in the amount of biomass accumulated in different vegetative organs.

Effect of Lignin and RLDPE Soil Amendments on Water Holding Capacities of Desert

The influence of recycled low density polyethylene (RLDPE) with different sizes and lignin soil amendments on dry bulk density (BD), water holding capacities (WHC) including saturated soil moisture content (SSMC), and moisture content at wilting point (MCWP) of desert was investigated. Results obtained show that BD decreased with the lignin and RLDPE added in desert. Lignin could significantly improve SSMC of desert soil. SSMC increased with the addition of RLDPE when the weight of RLDPE was less than 20 wt%, while its content was more than 20%, SSMC appeared a sharp decline. As for MCWP (5, 10, 15 and 20 wt%), it showed that the lignin presented dramatically positive effect, while RLDPE with different sizes presented slightly negative effect. Smaller particle sizes of RLDPE showed apparently the impact on soil properties in comparison with larger ones. It is hopeful that both lignin and RLDPE may be potential soil amendments for improving WHC of desert.