Effect Of Different Organic Materials Research Articles

Performance of Different Organic Fertilizers on Wheat Yield at Tikapur, Kailali

A field experiment was carried out to investigate the effect of different organic materials alone and in combination on the yield of wheat variety Aditya during November 2021- April 2022 in the Agronomy Field of Far Western University, Tikapur, Kailali. The study was carried out with 7 treatments viz. Farmyard manure (FYM), Vermicompost (V), Trichoderma viridae (T), FYM + V (FV), FYM + T(FT), FYM + V + T(FVT) and Control (without any organic matter) and laid out in Randomized Complete Block design with three replications. Chemical fertilizers were not used in the study. The result showed significantly higher number of effective tillers, thousand grain weight and grain yield in the treatment FVT as compared to other organic fertilizers and their combinations. But plant height was found to be the highest in FT followed by FYM. An increase of 16% and 36.29% grain yield was recorded in FVT over FT and the control respectively. Wheat grain yield from FV (2.28 t/ha) and FT (2.08 t/ha) were statistically greater than FYM or Vermicompost when applied alone. Application of Vermicompost and VT had relatively lower influence on yield attributes and yield as compared to FYM and FT. However, all the treatments were superior over the control in terms of all the yield and yield attributing traits.

Higher improvement in soil health by animal-sourced than plant-sourced organic materials through optimized substitution

Organic material input can improve soil health and mitigate adverse environmental consequences; however, there is controversy regarding the promoting effects of organic material inputs on soil health due to a lack of quantitative information on the effects of different organic materials from agricultural sources on soil health. This study proposed a novel soil health evaluation method using tree-structured machine learning algorithms to quantitatively assess the effects of animal-sourced (AS) and plant-sourced organic materials (PS) on soil health. The results demonstrated that in the testing set, the two ensemble models, random forest regressor (RFR) and light gradient boosting machine regressor (LightGBMR), showed high coefficient of determination (R2) of 0.879 and 0.877, respectively, and relative percent deviation (RPD) of 2.83 and 2.84, respectively (P < 0.001). Our findings indicated that the application of AS resulted in superior improvement of soil health for rice, wheat, and maize in comparison to PS. Compared with chemical fertilizer (CF), AS improved soil health indices (SHIs) for rice, wheat, and maize by 23.8–39.8%, PS improved SHIs for rice, wheat, and maize by 13.4–24.4%, and AS + PS improved SHIs for rice, wheat, and maize by 16.0–35.4% (P < 0.001). In addition, the positive effect of AS on SHIs was greater than that of PS. Compared with PS, the SHIs for rice, wheat, and maize increased by 7.34–14.9% for AS (P < 0.001). The reasonable nitrogen (N) application rates for rice, wheat, and maize were 262–290, 235–259, and 299–331 kg ha−1 year−1, respectively. Based on the positive feedback effects on soil health, the reasonable AS substitution rates for rice, wheat, and maize were 26.4–29.2%, 27.0–29.8%, and 29.6–32.8%, respectively. This study confirmed that organic materials improve soil health through optimized substitution, thus contributing to sustainable agricultural management and reducing adverse environmental impacts.

The Effects of Different Organic Materials and Cover Thicknesses on the Early Growth and Antioxidant Response of Direct-Seeded Rice

Direct-seeded rice (Oryza sativa) (DSR) is gaining increasing acceptance worldwide because it saves both time and labor. A covering treatment is a simple method to improve early plant growth under direct-seeding conditions. Herein, field experiments were conducted to study the effects of different powdered organic covering materials, i.e., organic fertilizer, seedling substrate, nutrient soil A, and nutrient soil B. In addition, the effects of different covering thicknesses were studied, including 5, 10, 15, and 20 mm, on the germination and early growth of DSR varieties. The two rice varieties Wufengyou 286 and Zhongjiazao 17 were used for this study. The seedling substrate at 15 mm and nutrient soil A at 5 mm covering thickness significantly increased the rate of germination of Wufengyou 286 by 43.93% and 40.26%, respectively, compared to the control treatment. Organic fertilizer, seedling substrate, and nutrient soil A at covering thicknesses of 5 mm significantly increased the germination rate by 42.57%, 38.62%, and 40.10%, respectively, compared to the control. Notably, all the treatments increased the emergence rate, with Wufengyou 286 exhibiting the most pronounced effect. The seedling substrate at 10 mm covering thickness significantly increased the rate of emergence of Wufengyou286 by 15.42% compared to the control. Similarly, the seedling substrate at 10 mm covering thickness gave the best results by increasing the rate of emergence of Zhongjiazao 17 by 10.85% compared to the control. On average, the rate of emergence of Wufengyou 286 and Zhongjiazao 17 under the experimental treatment increased by 11.81% and 6.45%, respectively, compared to the control. The appropriate cover treatment enhanced the early growth of DSR by improving its morphological attributes, such as plant height and dry weight, and regulating the physio-biochemical responses, such as the production of antioxidants and photosynthetic pigments. The seedling growth rate of both varieties decreased as the thickness increased. This study elucidated the effects of different covering materials on the early growth of DSR, which can further guide their actual production.

The Effects of Partial Substitution of Fertilizer Using Different Organic Materials on Soil Nutrient Condition, Aggregate Stability and Enzyme Activity in a Tea Plantation.

Fertilization plays a crucial role in enhancing tea production. However, it has been demonstrated that the long-term single application of chemical fertilizer will reduce soil nutrient content and the formation of soil aggregates, which is not conducive to the sustainable development of soil and agriculture. Many studies have shown that partial substitution of chemical fertilizer with organic fertilizer can improve soil physicochemical properties and soil nutrient content. This study compared the effects of different organic materials as substitutes for chemical fertilizer. We partially replaced chemical fertilizer with rabbit manure, wine lees and rapeseed cake, amounting to 30% of the total annual nitrogen application in the field experiment, and we set nine different fertilization methods to assess and analyze the soil nutrient condition, aggregate stability and enzyme activity. The results showed that the experimental soil aggregate mean weight diameter (MWD) and geometric mean diameter (GMD) were significantly increased compared with control (p < 0.05); the aforementioned fertilization methods also decreased the soil aggregate fractal dimension (D), disruption rate (PAD), average weight-specific surface area (MWSSA) and soil erodibility factor (K). The application of the fertilizer containing organic materials and microbial agent increased soil organic carbon (SOC) by 20.7% to 22.6% and total nitrogen (TN) by 34.6% to 38.1%; it also significantly promoted sucrase, urease and protease activities in all aggregate sizes (p < 0.05) and increased the 2-5 mm aggregate content. The correlation coefficients between the SOC and the enzyme activities were 0.18-0.95, and most of them showed an extremely significant positive correlation (p < 0.01). In conclusion, the application of fertilizers containing organic materials and microbial agents can improve soil aggregate stability, aggregate enzyme activity and soil structural stability.

Effect of different organic materials on some chemical properties of some soils in Delta region

Effect of different organic materials on some chemical properties of some soils in Delta region

Different organic material amendments effects soil nitrogen utilization and crop yield in the North China Plain

AbstractOrganic materials incorporation and nitrogen utilization are both important measures to enhance soil fertility and crop productivity. To evaluate the effect of different organic materials on soil N utilization and crop yield, three kinds of organic materials, including straw (ST), pig manure (PM), and biogas residue (BR), were incorporated into the soil with equal N in the wheat (Triticum aestivum L.)–maize (Zea mays L.) cropping system with chemical fertilizers (CFs) as a control in Wuqiao County in the North China Plain. The contents of soil N, nitrate N, ammonium N, N use efficiency, N partial productivity (NPFP), N uptake efficiency (NUPE), and N harvest index (NHI) were measured and calculated. The results of 2‐yr field trials suggested that, compared with CF, soil total N (TN) content of ST, PM, and BR treatment increased by 3.04, 8.99, and 9.10%, respectively. An even larger increase was found in nitrate N, which was 25.87, 44.67, and 44.93% in ST, PM, and BR, respectively. For N utilization, PM significantly increased NPFP, NUPE, and NHI by 4.01, 5.86, and 3.04%, respectively, meanwhile decreasing soil N dependency rate by 4.64%; BR improved NUPE by 5.15%, while ST showed little improvement in the utilization of soil N. Overall, organic materials promoted soil N maintenance and increased N utilization. Among the kinds of organic material amendment in the study, PM had a better performance in improving soil N utilization and crop yield than BR and crop ST return in field experiments.

Farklı Organik Atık Uygulamasının Toprak Kalitesi Üzerine Etkisinin SMAF Modeli ile Belirlenmesi

Soil is an essential resource for terrestrial life. That’s why it is vital to use it without causing any harm to its ecological and economic functions. This current study was carried out to investigate the effect of different organic materials (farmyard manure, vermicompost, leonardite, rose pulp, biochar, biogas waste, seaweed) on soil quality using the SMAF model in Isparta province, which has a semi-arid ecological characteristic. Thirteen soil quality indicators were used to determine the physical, chemical, and biological soil quality of the SMAF model. In this study, twelve indicators were used, which were: bulk density, aggregate stability, available water content, water-filled pore space, organic carbon, pH, electrical conductivity, sodium adsorption ratio, available potassium and phosphorus, microbial biomass carbon, and ßeta-Glucosidase enzyme activity. In general, the applied organic wastes had a positive effect on the quality characteristics of the soils. The lowest quality was determined in the control (50%) and seaweed (51%) applications, while the highest quality increase was determined in the rose pulp application (60%) and vermicompost application (56%). Other applications did not cause significant changes according to SMAF scoring. The most important effects of low quality scores were determined as biological quality indicators. According to the results obtained, organic waste application for sustainable soil management has an important place in increasing the physical, chemical, and biological soil quality properties of agricultural soils, especially in the arid and semi-arid areas of our country, as well as increasing the general soil quality index values.

Organic Materials Could Improve the Phytoremediation Efficiency of Soil Potentially Hazardous Metal by Sedum alfredii Hance

Soil potentially hazardous metal (PHM) is continually attracting public attention worldwide, due to its highly toxic properties and potentially huge damage to human being through food chain. Phytoremediation is an effective and eco-friendly way in remediation technology. A pot experiment was carried out to investigate the effect of different organic materials (biogas residue (BR), mushroom residue (MR), and bamboo-shoot shell (BS)) application on phytoremediation of two PHM-contaminated soils (Fuyang soil as ‘heavily-polluted soil’ and Wenzhou soil as ‘moderately-polluted soil’, respectively) by Sedum alfrecdii Hance. The results indicated: 1) for moderately-polluted soil, the 5% BR treatment had the strongest activation to Cu and Zn, for heavily-polluted soil, 1% BS treatment had the highest activation effect for Cu, Zn, Pb and Cd. 2) the above-ground biomass of Sedum alfredii Hance increased with the addition rate of organic materials. 3) for Cd uptake of Sedum alfredii Hance in moderately-polluted soil, only 1% BS treatment had a better accumulation effect, compared to the control, for Zn element, MR treatments were weaker than the control, while other treatments were better than the control, of which 5% BR, 1% BS and 5% BS accumulated more Zn element by 39.6%, 32.6% and 23.8%, respectively; in heavily-polluted soil, the treatments of 5% BS, 1% BR and 5% BR accumulated more Cd than the control by 12.9%, 12.8% and 6.2%, respectively, the treatments with organic materials addition promoted Zn accumulation in shoots of Sedum alfredii Hance, and the best treatment was 5% BS. Therefore, an appropriate application rate of BS and BR could improve the remediation efficiency for Zn/Cd contaminated soils by Sedum alfredii Hance.

Effects of Different Organic Materials on Absorption and Translocation of Arsenic and Cadmium in Rice

A pot experiment was carried out to study the impacts of five organic materials (rape straw, broad bean stalk, peat, pig manure compost, and biochar) on the availability of arsenic (As) and cadmium (Cd) in soil, the amount of iron plaque on the root surface, as well as the uptake and translocation of As and Cd in rice grown in an As/Cd co-contaminated yellow paddy soil. The results indicated that the application of organic materials significantly increased the contents of the soil organic matter and the yield of rice. The application of broad bean stalk, peat, pig manure compost, and biochar remarkably increased the soil pH, while the application of rape straw exerted no significant influence. The addition of organic matter reduced the available Cd content by 34.77%-82.69%. However, the effects of organic materials on the availability of As varied with the organic materials. The soil-available As content was significantly increased by the application of pig manure compost and biochar, while it was significantly decreased by adding rape straw and peat. The application of organic materials increased As and Cd contents in the Fe plaques on rice root surface by 28.49%-94.86% and 17.73%-151.03%, respectively. It also reduced the As and Cd contents in brown rice by 27.04%-82.51% and 15.87%-79.45%, respectively. The largest decrease was observed in the biochar treatment. The application of organic materials also remarkably reduced the translocation efficiency of Cd from the root-stem-leaf-grain and that of As from the stem to grain. The correlation analysis revealed that the soil pH, available Cd, and Cd content in the Fe plaques are the major factors influencing the accumulation of Cd in the rice grain. Furthermore, the soil pH, soil organic matter, and As content in the Fe plaques are the major factors influencing the accumulation of As in the rice grain. Therefore, it has been concluded that organic materials could influence the uptake and translocation of As and Cd in rice through changing the soil pH, organic matter content, and As and Cd contents in the Fe plaques.

Effects of different organic materials on soil compaction and least limiting water range Abstract

Toprak sıkışması ve buna bağlı toprağın gözenek yapısının değişimi, tarımsal sürdürebilirliği ve bitkisel verimi olumsuz yönde etkilemektedir. Bu olumsuz etkinin azaltılması için çeşitli amenajman uygulamalarının yanında, toprakların organik madde içeriklerinin artırılması önemli bir yer tutmaktadır. Ayrıca son yıllarda, toprak sıkışmasının toprağın fiziksel kalitesine etkisini belirlemede sınırlayıcı su aralığı (SSA) kullanılmaya başlanmıştır. Yapılan bu çalışmada, yüksek sıkışma potansiyeline sahip kil tekstür sınıfına sahip bir toprağa, ağırlıkça %0, 0.5, 1.0, 2.0 ve 4.0 oranlarında uygulanan sığır gübresi (SG), biyokömür (BK) ve kompostun (KO), altmış günlük inkübasyon sonunda, standart proktor testinde maksimum düzeyde sıkıştırılan örneklerin hacim ağırlığı (HA), toplam gözenekliliği (TG), tarla kapasitesi (TK), solma noktası (SN), faydalı su kapasitesi (FS) ve SSA üzerine etkileri belirlenmiştir. Buna göre, kontrol (K) örneği ile kıyaslandığında SG, BK ve KO uygulama dozlarındaki artış ile ters orantılı olarak toprağın maksimum HA değerleri azalmış ve TG değerleri ise artış göstermiş, %4 SG, BK ve KO uygulama dozlarında HA değerleri kontrole göre sırasıyla; %12.93, 11.56 ve 14.28 oranında düşerken, TG değerleri de sırasıyla; % 16.18, 14.38 ve 17.98 oranlarında artış göstermiştir. Ayrıca SSA’ nın alt ve üst limitleri uygulamalara bağlı olarak önemli değişkenlikler göstermiş, kullanılan organik materyallerin dozlarındaki artış ile önemli artışlar ölçülmüştür. SSA’ da en yüksek artış kompost uygulamasında %4 dozunda tespit edilmiştir. Buna göre sıkışma eğilimi yüksek ve fiziksel kalitesi düşük olan bir toprağa uygulanan her üç organik materyal de çalışma şartlarında toprağın sıkışma eğilimini azaltarak SSA’ yı genişletmiş ve toprağın fiziksel kalitesini yükseltmiştir.

Effects of Different Organic Materials Application on Soil Physicochemical Properties in a Primary Saline-Alkali Soil

The application of agricultural wastes to the soil does not only improve soil fertility but also helps in the recycling of agricultural waste resources. However, the effects of agricultural organic materials on soil physicochemical properties in primary saline and alkaline lands unsatisfactory. In this study, the effects of different organic materials on the physicochemical properties of primary saline-alkali soil were studied in the west of Jilin province for two consecutive years. The organic materials included: grass (FG), sheep manure (SM), coarse corn straw (CS), and granular corn straw (GS). Soil pH, EC, total salt content, CEC, exchangeable sodium, ESP, organic matter, field capacity, water immersed bulk density, sedimentation coefficient, hardness and the morphological characteristics of soil aggregates were measured by conventional methods. CEC, SOM, and the physical properties varied significantly among the different treatments, whereas pH, EC, total salt content and exchangeable sodium did not. Moreover, the morphology of the organic materials significantly affected pH, EC1 : 5, total salt content, SOM and physical properties of the soil however, it did not affect the CEC, exchangeable sodium and ESP. Comparing granular corn straw with coarse corn straw, granular corn straw increased the SOM and field capacity by 48.5 and 17.0% respectively and decreased the pH, EC1 : 5, total salt content, water immersed bulk density, sedimentation coefficient and soil hardness by 2.6, 2.4, 3.7, 11.3, 6.2 and 7.7% respectively. In conclusion, the application of organic materials effectively improved the physical and chemical properties in the saline-alkali soil however did not cause a complete change in the saline-alkaline nature of the soil. The morphology of the organic materials also significantly affected soil properties, with granular corn straw having a better effect than the other treatments.

Crop residues activity against the free-living stages of small ruminant nematodes.

The nematicidal effect of different organic materials was evaluated in order to develop a non-chemical alternative soil treatment for control of the free-living stages of small ruminant gastrointestinal nematodes. The selected organic materials were residues from the juice industry of acerola, cashew, grape, guava, papaya and pineapple, as well as castor residue from the biodiesel industry. LC90 results showed that pineapple residue was the most efficient inhibitor of larval development, followed by castor, grape, cashew, acerola, guava and papaya. Castor residue was also a good source of nitrogen and was used in a greenhouse experiment to prevent larval development in contaminated goat faeces that was deposited in pots containing the grasses Brachiaria brizantha (var. Paiaguás) or Megathyrsus maximus x M. infestum (var. Massai). Castor residue caused a significant (P < 0.05) reduction (85.04%) in Paiaguás grass contamination (L3.dry mass-1) and a reduction of 17.35% in Massai grass contamination (P > 0.05), with an increase in the biomass production of Massai (251.43%, P < 0.05) and Paiaguás (109.19%, P > 0.05) grasses. This strategy, called Econemat®, with good results in vitro shows to be promising on pasture increasing phytomass production.

Effects of long-term various organic materials incorporation on characteristics of soil quality and crop yield

In order to study the effects of different organic materials on soil quality and crop yield, a seven -year, s field experiment was conducted in North China Plain. The experiment included six treatments: no organic materials (CK), compost (C), Cow Dung (PM), biogas residue (BgR), crop straw (Str), biochar (BC), all samples were separated into four aggregate-size classes by wet sieving, meanwhile we calculated the mean weight diameter (MWD), geometric mean diameter (GMD), fractal dimension (D) and unstable aggregate index (ELT) of water-table aggregates. Compared with the CK treatment, the application of organic materials in 0~15 cm soil layer not only significantly increased MWD, GMD) of water-table aggregates (P<0.05), but also decreased the D and ELT of water-table aggregates. Also, the content of soil organic carbon (SOC) and total nitrogen (TN) increased significantly under different organic materials treatments (P <0.05), therefore, the nutrient content and structural stability of soil was significantly enhanced. The total yield of wheat and maize of C, PM, Bg, S and BC treatments increased by 75.5%, 69.7%, 108.9%, 34.1% and 1.0%. The improvement effects of aggregate stability index and soil structure of BC and Str treatments were the best, while C, BC and BgR treatments were better to increase the content of SOC and TN in bulk soil. The application of organic materials could increase the content of SOC and TN, enhance the soil water-stability aggregate stabilization and soil fertility, while increase crop yield.

Comparative effects of different organic materials on nematode community in continuous soybean monoculture soil

Plant parasitic nematodes are the most devastating pest in continuous soybean monoculture, which have been managed mainly by chemical nematicides. However, safe and alternative methods need to be developed. A variety of organic materials are used for this purpose, but the control efficiency of different organic materials for nematodes has not been assessed in a comparative manner. Therefore, based on a 7-year experiment of continuous soybean monoculture, we directly compared the effects of different organic materials (maize straw combined with chemical fertilizer (F + S), poplar leaf combined with chemical fertilizer (F + L), cow manure combined with chemical fertilizer (F + C) and only fertilizer as CK) on nematode trophic groups and functional guilds under the same condition. Despite the lack of total nematode density differences, organic materials altered the soil nematode community in a soybean monoculture system. The relative abundance of plant parasites was highest in F + L treatment, followed by F + S treatment, while lowest in F + C and CK treatments. Meanwhile, bacterivores and fungivores had a higher relative abundance in CK and F + C treatments and a lower relative abundance in F + L and F + S treatments. Furthermore, significant treatment effects were also observed on the relative abundance of different functional guilds, except colonizer-persister (c-p) 5 plant parasites. The relative abundance of c-p 2 bacterivores was significantly higher in CK and F + C treatments than in F + S and F + L treatments, while the relative abundance of c-p 3 omnivore-carnivores was significantly higher in F + S and F + L treatments than in CK and F + C treatments. Organic materials treatments had a significant effect on Shannon index (H’), plant parasite index (PPI), structure index (SI) and enrichment index (EI) (P < .05), and the significant effects varied among different organic materials treatments. The results of this study suggest that the influence on the soil nematode community of organic materials is associated with their chemical composition, and so is its efficacy of controlling plant parasitic nematodes.

Performance of watermelon (Citrullus lanatus L.) in response to organic and NPK fertilizers

AbstractThe soil of North-Central Nigeria is home to many plant products that are used as industrial raw materials, and after processing their waste are often left in drainage channels, which ultimately find their way into rivers and streams where they pollute these water bodies, and sometimes some of these materials are burnt, which further aggravates global warming. In addition, the soil of the region is characterized by low organic matter content because of annual bush burnings, which reduce the low humus content of soils. Watermelon requires a fertile soil, which is high in organic matter content, while infertile soils yield an increased production of male flowers at the expense of female flowers, which results in low fruit set. Therefore, a study was carried out at the University of Ilorin Teaching and Research Farm, Ilorin, North-Central Nigeria, during the rainy seasons of 2013 and 2014 to assess the effect of different organic materials on the growth and yield of watermelon. The factors imposed were a control, NPK fertilizer and five organic materials (neem seed cake (NSC), jatropha seed cake (JSC), poultry manure (PM), compost manure (CM), and cow dung (CD)). The experiment was a randomized complete block design (RCBD) replicated thrice. Data collected on soil physico-chemical properties were: organic matter content, soil pH, organic carbon, total N, P, K, Ca, and Mg, bulk density (BD), micro porosity (MIP), macro porosity (MAP), and saturated hydraulic conductivity (KS). Plant parameters evaluated include growth (vine length and number of leaves) and yield (number of fruits per plant, fruit weight per plant, and yield ha−1). Results indicated that the organic matter content increased after the first year’s cropping and declined at the end of the study. The amended plots showed significantly higher values (P &lt; 0.05) with respect to most soil physical properties (MIP), (MAP), and (KS), except the BD, where the values were lower. The bulk density particularly deteriorated on soils that were not organically amended. In addition, the soil chemical properties examined increased following the first year’s cropping, and thereafter declined at the end of the second-year cropping season. The response of watermelon showed that the two years’ yield data ranged between 334 and 402 t/ha, 306 and 390 t/ha, and 38.25 and 59.20 t/ha for NPK, poultry manure, and control treatments respectively. From the results, it was observed that the organic amendments were environmentally more friendly compared to the inorganic amendment (NPK fertilizer) in terms of positive effects on soil structural properties.

Evaluation of Different Organic Materials in Reducing Cadmium Phytoavailability of Radish Grown in Contaminated Soil

Various types of organic materials could affect differently immobilization of cadmium (Cd) and its uptake by plant grown in soil. Therefore, this study was conducted to evaluate effect of different organic materials in reducing Cd phytoextractability in contaminated arable soil. To do this, rice straw and composted manure were selected as organic materials and applied at the rate of 0, 15, 30, and 45 Mg ha-1 in Cd contaminated arable soil with 6.5 mg kg -1 of total Cd. Radish (Raphanus sativa L.) was seeded and grown for 50 days to evaluate Cd phytoavailability with different organic materials. Composted manure was more effective to decrease 1 M NH₄OAc extractable Cd concentration and increase pH of soil than rice straw. One M NH₄OAc extractable Cd concentration significantly decreased with increasing application rate of composted manure. Tendency of Cd uptake by radish plant with application of different organic materials was similar to that of 1 M NH₄OAc extractable Cd concentration and soil pH. Changes of soil pH with application of straw and composted might be one of factors to determine extractability and phytoavailability of Cd in this study. Radish yield significantly increased with up to 45 Mg ha -1 of composted manure application but did not with straw application. In the view point of Cd phytoextractability and plant productivity, it is recommended to apply composted manure rather than straw in Cd contaminated arable soil.

Effects of Different Organic Materials on Bio-availability of Cd, Pb in a Contaminated Greenhouse Soil

A two-season soil culture experiment was continually conducted to study the effects of three organic materials,namely Danty, Peat and Biochar,respectively,on combined forms and bio-availability of cadmium (Cd) and lead (Pb) under Cd and Pb in single and combined pollution during 2014-2015. This study aimed to provide a theoretical basis for remediating greenhouse soil contaminated with heavy metals Cd and Pb using organic materials. The main results were as follows: the content of DTPA-Cd decreased significantly by 11.9%(P<0.05) in the soil of Cd and Pb combined pollution with the application of danty, the total of exchangeable Cd, carbonate-bound Cd and iron-manganese oxide bound Cd was reduced by 26.4% and 34.4% in the soil, and the accumulation of Cd in shoots was significantly cut down by 32.0% and 28.0% (P<0.05) respectively in Cd single and Cd and Pb combined pollution after applying danty; the content of DTPA-Pb was significantly depleted by 83.5% and 83.8%(P<0.05), the total of exchangeable Pb, carbonate-bound Pb and iron-manganese oxide bound Pb was decreased by 34.5% and 13.9% in the soil and the accumulation of Pb in shoots was significantly reduced by 32.0% and 30.0% (P<0.05) in Pb single and Cd and Pb combined pollution respectively as the use of danty. The content of DTPA-Cd was significantly decreased by 18.9% (P<0.05) in the soil of Cd and Pb combined pollution with the use of peat, the accumulation of Cd in shoots was reduced by 38.0% and 23.4%(P<0.05) in Cd single and Cd-Pb combined pollution respectively after the application of peat; The content of DTPA-Pb was significantly decreased by 2.7% and 7.2%(P<0.05), the total of exchangeable Pb, carbonate-bound Pb and iron-manganese oxide bound Pb was decreased by 15.8% and 14.6% in the soil and the accumulation of Pb in shoots was significantly reduced by 12.7% and 23.4% (P<0.05) respectively in Pb single and Cd and Pb combined pollution due to the application of peat. The pH value of the soil was increased by the use of biochar, the content of DTPA-Cd was reduced by 4.7% and 15.0% respectively in the soil of Cd single and Cd and Pb combined pollution, and the accumulation of Cd in shoots was significantly minified by 38.0% and 23.4% respectively in Cd single and Cd and Pb combined pollution as the application of biochar. The content of DTPA-Pb was decreased by 6.8% and 1.0% and the total of exchangeable Pb, carbonate-bound Pb and iron-manganese oxide bound Pb was cut down by 11.9% and 30.0% in the soil of Pb single and Cd and Pb combined pollution respectively by the application of biochar. The content of Cd in plant was most significantly positively correlated with the content of exchangeable Cd in soil (P<0.01). The content of Pb in plant was most significantly positively correlated with the total of exchangeable Pb, carbonate-bound Pb and iron-manganese oxide bound Pb (P<0.01). In summary, after the application of danty, peat and biochar, the proportion of highly active content of Cd and Pb was minified through adjusting soil pH and immobilizing Cd and Pb by means of adsorption and complexation in greenhouse soil. With the analysis of input-output, the application of danty, peat and biochar costs 4050 yuan·hm-2, 11250 yuan·hm-2 and 22500 yuan·hm-2, respectively. Thus danty, peat and biochar could be used as effective organic agents in the remediation of Cd and Pb contaminated greenhouse soil.

Effect of Different Organic Materials on Nitrogen Mineralization in Two Purple Soils

An aerobic incubation experiment was conducted at a constant temperature to investigate the differences in nitrogen mineralization between an acid purple soil and a calcareous purple soil amended with five organic materials including biogas residues of pig manure(PM), cow manure(CW), sewage sludge compost(SC), rural waste compost(RWC1)and the compost of rural waste plus 20% of sewage sludge(RWC2). The results showed that the organic nitrogen forms in these materials followed the order of amino acid N> hydrolysable unidentified N> ammonium N> non-hydrolysable N> amino sugar N. Application of organic materials could significantly improve the contents of NH4⁺-N and NO3^--N in acid purple soil, PM and SC could significantly improve the content of NH4⁺-N, but CM reduced the content of NO3^--N in calcareous purple soil. Except for CM, which had no significant effect on the quantity of nitrogen mineralization in acid purple soil, but decreased the quantity of nitrogen mineralization in calcareous purple soil, applying the organic materials could significantly increase the quantity of nitrogen mineralization in both soils. Correlation analysis showed that the quantity of nitrogen mineralization was significantly and positively correlated with the contents of amino acid N and ammonium N, but were significantly and negatively correlated with the content of organic matter and the C/N of organic materials. Overall, the results illustrated that the effect of organic materials on the mineralization of nitrogen varied with soil types and the characteristics of organic materials, especially the content of organic matter, C/N and the fractions of organic nitrogen in organic materials.

Effects of different organic materials on forage yield and nutrient uptake of silage maize (Zea mays L.)

ABSTRACTThe use of organic materials as a source of nutrients on agricultural lands ameliorates soil physical properties as well as being an environmentally friendly way of disposing of their wastes. This study was conducted to determine effects of three organic materials (poultry litter, cattle manure, leonardite) on yield and nutrient uptake of silage maize. Poultry litter and cattle manure were applied based on phosphorus (P) or nitrogen (N) requirements of the crop whereas leonardite was applied only one dose (500 kg ha−1) and also combined with three inorganic fertilizer doses (100%, 75%, 50% of recommended inorganic fertilizer dose). According to the results, the highest green herbage yield and nutrient uptake values were observed in LEO-100 whereas N-based treatments significantly decreased yield and nutrient uptake of silage maize. The use of organic materials as a combination with inorganic fertilizer in silage maize cultivation is highly beneficial for sustainable forage production.

Effects of Different Organic Materials on Contents and Morphologic Changes of Mn in Black Soil

Three kinds of organic materials were used for culture experiment, namely livestock manures, natural organic materials and half decomposed organic materials. And the modified BCR sequential extraction procedure was used to analyze the morphologic changes of Mn. The study was focus on the effects of different kinds of organic materials on contents and morphologic changes of Mn in black soil. And the results show that different kinds of organic materials all increase the total Mn contents in soil. The amplifications of livestock manures and natural organic materials are higher then half decomposed organic materials. Comparing with fertilizers only, all kinds of organic materials increase the contents of each Mn fraction. For Weak acid soluble (Aci.) fraction of Mn, natural organic materials increase most, for Reducible (Red.) fraction, livestock manures increase most, for Oxidizable (Oxi.) fraction, all kinds of organic materials are nearly the same, and for Residual (Res.) fraction, livestock manures increase most. In addition, different kinds of organic materials also lead to morphologic transformation of Mn, comparing with fertilizers only, livestock manures lead to inert transformation, while natural organic materials lead to active transformation, and half decomposed organic materials lead to inert transformation.