Evaluation of selected medicinal plant materials and dicyandiamide on nitrification of urea‐derived ammonium under laboratory conditions     

Majid Mahmood Tahir  Shahida Begum  Mehdi Maqbool  Abdul Khaliq  Noosheen Zahid  Khalid Mehmood  Muhammad Shehzad 《植物养料与土壤学杂志》2021,184(1):132-141

Background : Poor utilization of urea fertilizer and N losses from agriculture lands demands alternate fertilization practices to reduce N losses and improve utilization, i.e., application of nitrification inhibitors. Aims : This study was aimed to evaluate and compare the influence of dicyandiamide (DCD) and selected medicinal plant materials and on N transformations, nitrification inhibition and recovery of applied N. Methods : Treatments included: urea nitrogen (UN), UN + DCD, UN + Gingiber officinale, UN + Viola odorata, UN + Sewertia chirata, UN + Azadirachta indica, UN + Sphaenathus indicus, UN + Allium sativus, UN + Artemisia absenthium, UN + Fumaria indicus, UN + Caesalpinea bondusella, UN + Barberis lyceum, and an un‐amended control. Urea was applied at 200 mg N kg^?1 soil, while DCD and medicinal plant materials were applied at of 1% and 20% of applied urea, respectively. Results : Medicinal plant materials inhibited nitrification of urea‐derived ${\mathrm{NH}}_4^{+}\text{-}N$. On an average of medicinal plant materials treatments, 51% of ${\mathrm{NH}}_4^{+}\text{-}N$ was still present in soil compared to 17% ${\mathrm{NH}}_4^{+}\text{-}N$ in UN treatment without medicinal plant materials after 28 days. Similarly, ${\mathrm{NO}}_3^{-}\text{-}N$ was 76.54 mg kg^?1 in UN treatment compared to 34.40 mg kg^?1 in UN + medicinal plant materials treatments, indicating 55% reduction in nitrification. Apparent nitrogen recovery (ANR) in UN treatment was 65% compared to 74% in UN + DCD treatment. ANR in treatments, where UN was amended with medicinal plant materials, varied between 58 to 70%. Conclusions : The use of DCD and medicinal plant materials with UN significantly reduced ${\mathrm{NH}}_4^{+}\text{-}N$ oxidation and nitrification ( ${\mathrm{NO}}_3^{-}\text{-}N$). In general, medicinal plant materials were more effective in regulating N transformations and, thus, offer a suitable alternate fertilization practice to reduce N losses and improve fertilizer utilization.  相似文献   

Plant Availability Index by Potassium Exchange Isotherms in Selected Rice Soils of Lesser Himalayas     

《Communications in Soil Science and Plant Analysis》2012,43(17):2073-2084

Potassium (K) exchange isotherms (quantity–intensity technique, Q/I) and K values derived from the Q/I relationship provide information about soil K availability. This investigation was conducted to study Q/I parameters of K, available K extracted by 1 N ammonium acetate (NH₄AOc) (exchangeable K plus solution K), K saturation percentage (K index, %), and the properties of 10 different agricultural soils. In addition, the relationship of mustard plant yield response to the K requirement test based on K exchange isotherms was investigated. The Q/I parameters included readily exchangeable K (ΔK₀), specific K sites (K_X), linear potential buffering capacity (PBC^K), and energy of exchange of K (E_K). The results of x-ray diffraction analysis of the oriented clay fractions indicated that some mixed clay minerals, illite clay minerals, along with chlorite/hydroxy interlayered vermiculite and kaolinite were present in the soils. The soil solution K activity ratio at equilibrium (AR₀) ranged from 8.0 × 10^?4 to 3.1 × 10^?3 (mol L^?1)^0.5. The readily exchangeable K (ΔK₀) was between 0.105 to 0.325 cmol_ckg^?1 soil, which represented an average of 88% of the exchangeable K (K_ex). The soils showed high capacities to maintain the potential of K against depletion, as they represented high linear potential buffering capacities (PBC^K) [13.8 to 50.1 cmol_c kg^?1/(mol L^?1)^0.5. The E_K values for the soils ranged from ?3420 to ?4220 calories M^?1. The percentage of K saturation (K index) ranged from 0.7% to 2.2%. Analysis of variance of the dry matter (DM), K concentrations, and K uptake of mustard plants indicated that there were no significant differences among the adjusted levels of K as determined by the exchange-isotherm curve.  相似文献   

Ammonium fertilization increases pearl millet yield by promoting early root growth,higher tillering,and water use during grain filling in a low P Sahelian soil     

Francesca Beggi  Vincent Vadez  Andreas Buerkert 《植物养料与土壤学杂志》2021,184(1):123-131

Background : Adaptation of pearl millet [Pennisetum glaucum (L.) R. Br.] to low soil phosphorus (P) at early seedling stages and efficient P fertilizer application are crucial for its survival in the West African Sahel. While addition of ${\mathrm{NH}}_4^{+}\text{-}N$ to P in the microdose technique has been reported to stimulate early growth of pearl millet, there is little information regarding root length (RL) at different timings. Aims : Our study aimed at assessing the effects of added ${\mathrm{NH}}_4^{+}\text{-}N$ and ${\mathrm{NO}}_3^{-}\text{-}N$ to P on (1) pearl millet agronomic traits such as root and shoot growth and (2) the water use dynamics during the cropping cycle. Methods : Twenty‐four “RhizoTubes” filled with P‐deficient soil were used to grow pearl millet under three treatments: (T1) placed P addition alone at 0.4 g per seed hole, P_placed, (T2) P_placed + ${\mathrm{NH}}_4^{+}\text{-}N$, and (T3) P_placed + ${\mathrm{NO}}_3^{-}\text{-}N$. At 2, 3, 4, and 5 weeks after sowing (WAS) we took non‐destructive measurements of RL. Water use (transpiration) was measured from 3.5 to 9 WAS. Results : At early growth, roots in the topsoil of T2 were longer than T3 and T1 roots (at 4 WAS: 129.3 cm for T2, 87.5 cm for T3, and 93.3 cm for T1, p < 0.05). Total RL at 2 WAS correlated positively with seedling height and final grain yield. Fertilization with ${\mathrm{NH}}_4^{+}\text{-}N$ reduced the time to flowering and increased the number of tillers and grain yield, whereas addition of ${\mathrm{NO}}_3^{-}\text{-}N$ increased vegetative dry matter at harvest and water use efficiency. Conclusions : Our findings suggest that fertilization with ${\mathrm{NH}}_4^{+}\text{-}N$ plays a critical root stimulating role at early growth stages, seemingly by increasing lateral root initiation, which carries through to a larger water use during grain filling and higher grain yield.  相似文献   

Quantity–Intensity Relationships and Potassium Buffering Capacity of Four Ganges River Floodplain Soils     

《Communications in Soil Science and Plant Analysis》2012,43(7-8):1333-1349

  相似文献   

Ammonium‐driven nitrification plays a key role in increasing Mn availability in calcareous soils     

Michael Dreyer  Merle Wichmann  Marie Rischen  Bruno M. Görlach  Annika Ehmke  Britta Pitann  Karl H. Mühling 《植物养料与土壤学杂志》2020,183(3):389-396

Background : Manganese deficiency often becomes a yield limiting factor, particularly on calcareous soils, even though the total soil manganese content is usually sufficient. Although it is known that acidifying N fertilizers can improve Mn availability, the reason of this effect is still unknown. Aim : Our aim was to investigate the effect of stabilized ammonium fertilizers as a tool to distinguish between physiological‐ and nitrification‐induced acidification. Method : Two pot experiments with Triticum aestivum L. and one soil incubation experiment using different nitrogen forms (CN = calcium nitrate, AN = ammonium nitrate, AS = ammonium sulfate, ATS = ammonium thiosulfate) with and without addition of nitrification inhibitors (DCD, Nitrapyrin, Piadin, DMPP) were conducted to examine the effect on Mn availability in the soil and Mn uptake by the plants at different development stages (EC 31 und 39). Results : With increasing fertilizer ${\mathrm{NH}}_4^{+}$ content a higher Mn concentration was detected: CN: 32 µg Mn g^?1 DM, AN: 39 µg Mn g^?1 DW, AS: 55 µg Mn g^?1 DM, ATS: 109 µg Mn g^?1 DM. The addition of a nitrification inhibitor resulted in a significantly lower rhizosphere pH compared to the non‐stabilized fertilizer. Surprisingly, the use of different nitrification inhibitors led to unchanged (CN, AN) or lower Mn concentrations of wheat. Especially in the ${\mathrm{NH}}_4^{+}$ treatments (AS and ATS), this negative effect was very evident (AS+DCD: 42 µg Mn g^?1 DM; ATS+DCD: 55 µg Mn g^?1 DM). Conclusions : Mn availability was enhanced by ongoing nitrification process rather than physiological acidification. Compared to other N forms, ammonium thiosulfate led to the highest Mn availability in bulk soil.  相似文献   

Investigating the spatio‐temporal variations of nitrate leaching on a tea garden hillslope by combining HYDRUS‐3D and DNDC models     

Xiaoming Lai  Ya Liu  Zhiwen Zhou  Qing Zhu  Kaihua Liao 《植物养料与土壤学杂志》2020,183(1):46-57

Spatio‐temporal variations of nitrate‐nitrogen ( ${\mathrm{NO}}_3^{-}$‐N) leaching is driven by both soil hydrology and biogeochemistry. However, the widely used soil hydrology and biogeochemistry models have their weaknesses in simulating soil N cycling and soil water movement processes, respectively. In this study, we proposed an alternative approach by simply combining the HYDRUS‐3D and DNDC models to investigate the spatio‐temporal variations of ${\mathrm{NO}}_3^{-}$‐N leaching on a representative tea garden hillslope in Taihu Lake Basin, China. Results showed that the soil hydrology and N cycle were well simulated by HYDRUS‐3D and DNDC models, respectively. Based on the leaching equation, the soil water flux simulated by HYDRUS‐3D and soil ${\mathrm{NO}}_3^{-}$‐N content simulated by DNDC were combined to calculate the leachate ${\mathrm{NO}}_3^{-}$‐N concentrations with good accuracy. The accumulative ${\mathrm{NO}}_3^{-}$‐N leaching flux during the simulation year was 71.7 kg N ha^?1, with remarkable spatio‐temporal variations on this hillslope. Hot spots of ${\mathrm{NO}}_3^{-}$‐N leaching were observed in blocks 24, 27, 31, 34, 37, and 40 with accumulative leaching fluxes > 82.0 kg N ha^?1 y^?1. The spatial variation of ${\mathrm{NO}}_3^{-}$‐N leaching was mainly controlled by soil texture and soil hydraulic properties. Hot moments of ${\mathrm{NO}}_3^{-}$‐N leaching were observed after the applications of spring fertilizer (16 March) and basal fertilizer (30 October). The temporal variation of ${\mathrm{NO}}_3^{-}$‐N leaching was mainly controlled by precipitation and the spring fertilization. Methods and findings of this study will be benefit for the risk assessment of non‐point source N loss and the precise agricultural management.  相似文献   

Co‐occurrence of organic and inorganic N influences asparagine uptake and amino acid profiles in white clover     

Weronika Czaban  Jim Rasmussen 《植物养料与土壤学杂志》2021,184(1):162-172

Background : Direct plant uptake of organic nitrogen (N) may be important for plant N nutrition, but we lack knowledge of how the concentration and form of external N influence organic N uptake and plant N status. Aims : We investigated the uptake of the amino acid asparagine (Asn) in white clover in the presence of different inorganic, organic and total N concentrations. Methods : Actively N₂‐fixing white clover seedlings were for one week exposed to combinations of ${\mathrm{NO}}_3^{-}$ (3–30 µmol N kg^?1 sand DW) and Asn (3–30 µmol N kg^?1 sand DW), whereafter the Asn uptake rate was determined by addition of ¹³C₄‐Asn. Shoot and root amino acid profiles were also analyzed. Results : Increasing ${\mathrm{NO}}_3^{-}$ and total N concentrations decreased ¹³C₄‐Asn uptake rates and internal clover Asn content. In addition, total N and ${\mathrm{NO}}_3^{-}$ also affected amino acid profiles, with Asn, Asp, Glu, Gln, Cys, Gly, Pro, Ser, and Ala being more related to the low N doses, and Thr, Val, Ile, Leu, Phe, Tyr, Trp, and Met being more abundant at increasing N doses. Conclusions : Asn uptake rate in white clover is reduced by increasing inorganic N. Plant amino acid profiles are likely to be a more sensitive indicator of N supply.  相似文献   

High concentrations of sodium and chloride ions have opposing effects on the growth of the xerophyte Pugionium cornutum under saline conditions     

Yan-Nong Cui  Fang-Zhen Wang  Jian-Zhen Yuan  Huan Guo  Suo-Min Wang  Qing Ma 《植物养料与土壤学杂志》2021,184(1):88-97

Background : The research on plant salt tolerance has mainly focused on Na⁺, but Cl^? has been relatively neglected. Previous studies have found that the xerophyte Pugionium cornutum, an important forage grass in the arid and semi‐arid regions of northwestern China, could synergistically accumulate high quintiles of Na⁺ and Cl^? in its shoots under NaCl treatments. However, the separate effects of these ions on the adaptation of P. cornutum to saline conditions have not been investigated. Aims : In this study, the response of P. cornutum to Na⁺ and Cl^? was analyzed. Methods : Four‐week‐old seedlings were treated with additional 50 mM NaCl, Na⁺‐specific solution containing 50 mM Na⁺ with a mix of ${\mathrm{NO}}_3^{-}$, H₂ ${\mathrm{PO}}_4^{-}$, and ${\mathrm{SO}}_4^{2-}$ as counter anions, and Cl^?‐specific solution containing 50 mM Cl^? with a mix of K⁺, Ca²⁺, and Mg²⁺ as counter cations. Results : Compared with the normal growth condition irrigated with Hoagland solution, the Na⁺‐specific solution severely impaired the growth and photosynthesis of P. cornutum due to the high accumulation of Na⁺ in shoots and the deterioration of tissue K⁺ homeostasis; while the Cl^?‐specific solution significantly increased shoot fresh and dry biomass. The Cl^?‐specific solution could also increase the turgor pressure in leaves for enhancing osmotic adjustment, which should be mainly attributed to the large accumulation of Cl^?, since the concentrations of other ions, including K⁺, Mg²⁺, Ca²⁺, H₂ ${\mathrm{PO}}_4^{-}$, and ${\mathrm{SO}}_4^{2-}$, in tissues under Cl^?‐specific treatment were maintained at the same levels as those observed under the normal condition. Conclusions : P. cornutum displays an excellent tolerance to moderate Cl^? but not to Na⁺, and the large accumulation of Cl^? should play a positive role in stimulating the growth of P. cornutum under salt stress.  相似文献   

Potassium is a potential toxicant for Arabidopsis thaliana under saline conditions     

Wenting Zhao  Franziska Faust  Sven Schubert 《植物养料与土壤学杂志》2020,183(4):455-467

Background and aims : Most physiological and biochemical studies on salt stress are NaCl‐based. However, other ions (e.g., K⁺, Ca²⁺, Mg²⁺, and ${\mathrm{SO}}_4^{2-}$) also contribute to salt stress in special circumstances. In this study, salt stress induced by various salts was investigated for a better understanding of salinity. Methods : Arabidopsis thaliana plants were stepwise acclimated to five iso‐osmotic salts as follows: NaCl, KCl, Na₂SO₄, K₂SO₄, and CaCl₂. Results and Conclusions : Exposure to KCl and K₂SO₄ led to more severe toxicity symptoms, smaller biomass, and lower level of chlorophyll than exposure to NaCl and Na₂SO₄, indicating that Arabidopsis plants are more sensitive to potassium salts. The strongly reduced growth was negatively correlated with the accumulation of soluble sugars observed in KCl‐ and K₂SO₄‐treated plants, suggesting a blockage in the utilization of sugars for growth. We found that exposure to KCl and K₂SO₄ suppressed or even blocked sucrose degradation, thus leading to strong accumulation of sucrose in shoots, which then probably inhibited photosynthesis via feedback inhibition. Moreover, K⁺ was more accumulated in shoots than Na⁺ after corresponding potassium or sodium salt treatments, thus resulting in decreased Ca²⁺ and Mg²⁺ concentrations in response to KCl and K₂SO₄. However, K₂SO₄ caused more severe toxicity symptoms than iso‐osmotic KCl, even when the K⁺ level was lower in K₂SO₄‐treated plants. We found that Na₂SO₄ and K₂SO₄ induced strong accumulation of tricarboxylic acid intermediates, especially fumarate and succinate which might induce oxidative stress. Thus, the severe toxicity symptoms found in K₂SO₄‐treated plants were also attributed to ${\mathrm{SO}}_4^{2-}$ in addition to the massive accumulation of K⁺.  相似文献   

Correlating phosphorus extracted by simple soil extraction methods with foliar phosphorus concentrations of Picea abies (L.) H. Karst. and Fagus sylvatica (L.)          下载免费PDF全文

Hadi Manghabati  Rasmus Ettl  Karl Mellert  Uwe Blum  Axel Göttlein 《植物养料与土壤学杂志》2018,181(4):547-556

Phosphorus (P) concentrations in needles and leaves of forest trees are declining in the last years in Europe. For a sustainable forest management the knowledge of site specific P nutrition/availability in forest soils is vital, but we are lacking verified simple methods for the estimation of plant available P. Within this study, four soil P extraction methods [water ( ), double‐lactate (P_lac), citric acid (P_cit), and sodium bicarbonate ( )], as well as total P content of the soil (P_tot) were tested to investigate which method is best correlated with foliar P concentrations of spruce [Picea abies (L.) H. Karst.] and beech [Fagus sylvatica (L.)]. Mineral soil samples from 5 depth levels of 48 forest sites of the Bavarian sample set of the second National Forest Soil Inventory (BZE II) were stratified according to tree species (spruce and beech) and soil pH (pH < 6.2 and > 6.2), covering the whole range of P nutrition. The extractable amount of P per mass unit of soil increased in the order << P_lac < < P_cit, decreased with soil depth, and was higher in soils with pH < 6.2. Citric acid extracted up to 10% of P_tot in acidic soils. Whereas P_cit delivers adequate regression models for P nutrition in the case of spruce (R² up to 0.53) and beech (R² up to 0.58) for acidic soils, shows good results for spruce growing on acidic soils (R² up to 0.66) and for beech on soils with pH > 6.2 (R² up to 0.57). P_lac produces adequate models only for beech on high pH soils (R² up to 0.64), while did not produce acceptable regression models. P_tot seems suitable to explain the P nutrition status of beech on acidic (R² up to 0.62) and alkaline soils (R² up to 0.61). Highest R²s are obtained mostly in soil depths down to 40 cm. As and P_cit showed good results for both investigated tree species, they should be considered preferentially in future studies.  相似文献   

Contribution of non-exchangeable potassium on its quantity-intensity relationships under K-depleted soils     

Fotis Bilias  Nikolaos Barbayiannis 《Archives of Agronomy and Soil Science》2013,59(14):1988-2004

ABSTRACT

Quantity-Intensity (Q/I) parameters were used for elucidating the role of buffering properties of soils through K depletion. Winter wheat was sown in a greenhouse pot experiment until K-depletion and soils were analyzed with NH₄OAc and NaBPh₄ (1 min incubation period). Q/I isotherms (partitioned in exchangeable and non-exchangeable form) were constructed for the soils before and at the end of the K-exhaustion experiment. Results showed that NaBPh₄-K correlated better than NH₄OAc-K with intensity parameter (AR_e^K) or labile K (-ΔΚ₀) in K-depleted soils (r = 0.41 and 0.70), indicating the importance of non-exchangeable K in K dynamics. The latter was confirmed from the comparison of buffering characteristics between initial and K-depleted soils which showed that among the soils studied there was a group whose increase in buffering capacity (PBC^K_t) was due to non-exchangeable K fixation. Furthermore, NaBPh₄-K was well predicted by the sum of exchangeable K and the quantity of K that has to be applied to achieve K balance as derived from Q/I isotherms (EK₀ + CK₀). Finally, relationships were found between Q/I parameters of the initial soils (-ΔΚ_0i, ΕΚ_0i, ΕΚ_ri, CK_0i) and the K-depleted ones (ΕΚ_rd, ΕΚ_0d, CK_0d, CK_rd) which allowed corresponding prediction of the initial parameters (r² = 0.78–0.87).  相似文献   

Soil incubation study showed biogas digestate to cause higher and more variable short‐term N2O and N2 fluxes than mineral‐N     

Caroline Buchen-Tschiskale  Ulrike Hagemann  Jürgen Augustin 《植物养料与土壤学杂志》2020,183(2):208-219

Today, a large share of mineral fertilizer is substituted by biogas digestates. Biogas digestates are known to promote N₂O production, compared to mineral fertilizer. In particular, the initial phase following fertilizer application is crucial for the N gas release as N₂O and also N₂. However, this period impact has been rarely investigated, especially not across various field sites. Thus, undisturbed soil cores from two fertilizer types (biogas digestate vs. mineral fertilizer) at five sites with different site characteristics were investigated in a short‐term laboratory experiment under N₂‐free helium–oxygen incubation atmosphere. Across sites, biogas digestate soil cores showed significantly higher absolute N₂O fluxes compared to mineral fertilizer soil cores, even though this effect was dominated by samples from one site (Dornburg with the highest biogas digestate fertilization rate). Also relative N₂O fluxes showed a similar tendency. On average, absolute and relative N₂ fluxes differed between the two fertilizer types, while N₂ fluxes were highest at the Dornburg site. A N₂O/(N₂O+N₂) ratio of denitrification below or equal to 0.5 clearly highlighted the importance of N₂O reduction to N₂ for three of five the biogas digestate soil cores. Soil characteristics like bulk density and water‐filled pore space as proxies for gas diffusivity in soil, as well as N availability ( ${\mathrm{NO}}_3^{-}$, ${\mathrm{NH}}_4^{+}$), significantly affected the N₂O and N₂ fluxes from the biogas digestate soil cores. While this study presents data on short‐term N₂O and N₂ fluxes, there is a need for further studies in order to investigate the dynamics, the duration of the observed effects and their significance at the field scale.  相似文献   

Performance of nitrification inhibitors with different nitrogen fertilizers and soil textures     

Gabriel Barth  Sabine von Tucher  Urs Schmidhalter  Rafael Otto  Peter Motavalli  Risely Ferraz-Almeida  Thales Meinl Schmiedt Sattolo  Heitor Cantarella  Godofredo Cesar Vitti 《植物养料与土壤学杂志》2019,182(5):694-700

Nitrification inhibitors (NIs), DCD (dicyandiamide), and DMPP (3,4‐dimethylpyrazole phosphate), in combination with urea (UR) and ammonium sulfate nitrate (ASN) fertilizers were studied under contrasting soil textures (sand, loam, and clay) from cultivated soils collected in Brazil and Germany. Soil samples were incubated over 50 days and the content of ammonium ( ), nitrate ( ), and soil pH were measured periodically. Applied NIs delayed the nitrification process across all soil textures. Correlation analysis indicated that combining ASN with NIs resulted in higher content and efficiency in delaying the nitrification process with high N‐conversion rate (r = –0.82). The combination of ASN+ DMPP increased the efficiency of the N‐conversion rate (r = –0.86) due to H⁺ release in soil, while UR+DCD (r = –0.50) had an efficiency of the N‐conversion rate similar to UR (r = –0.42). All the NIs had a better performance in reducing formation in sandy soils as compared to the loam and clay textured soils. Use of DMPP with an N fertilizer results in a soil pH decrease and can be an option to increase the efficiency of the N‐conversion rate, reducing N losses in soil. Overall, our results suggest that NIs have a better performance in reducing formation in sandy soils as compared to that of the loam and clay textured soils. Use of DMPP with ASN results in a soil pH decrease and can be an option to reduce N losses in soil.  相似文献   

Greenhouse gas emissions from decomposition of biosolids as affected by stabilization method and soil moisture     

Okenna Obi-Njoku  Michael Yongha Boh  Gordon W. Price  Andrea Gonzalez-Pavia  Osborne Grant Clark 《Soil Use and Management》2023,39(1):161-182

Computational models are useful to estimate agricultural greenhouse gas emissions at regional scales. However, empirically based parameter values are required for the models to accurately represent carbon (C) and nitrogen (N) mineralization rates of different organic amendments in more and less humid regions or during wet and dry periods of the growing season. A controlled environment study was conducted to assess the rates of C and N mineralization in differently processed sewage sludge (biosolids) in wet and dry soil. Parameter values were estimated for use in modelling the degradation of three types of biosolids. A loam soil with either 49% water-filled pore space (WFPS) or 29% WFPS was amended with mesophilic anaerobically digested (digested), alkaline-stabilized, or composted biosolids. Headspace samples were collected and analysed for carbon dioxide (CO₂) and nitrous oxide (N₂O), and soil samples for nitrate (${\mathrm{NO}}_3^{-}$) and ammonium (${\mathrm{NH}}_4^{+}$). Four different first-order models were fitted to the cumulative CO₂–C and N₂O–N data (R² > 0.98), and soil ${\mathrm{NO}}_3^{-}$ (R² > 0.65) and ${\mathrm{NH}}_4^{+}$ (R² > 0.93) concentrations. CO₂–C data indicated that C mineralization was higher in soil with 49% WFPS than in soils with 29% WFPS. Seventy-nine percent of the C compounds in digested biosolids degraded in soil with 49% WFPS, compared with 52% for alkaline-stabilized biosolids and 8% for composted biosolids. The fitted coefficient values were similar for all of the four first-order models used in this study and provide useful information for parameterizing more sophisticated mechanistic models of the degradation of biosolids in soil.  相似文献   

Response of soil exchangeable and crop potassium concentrations to variable fertilizer and cropping regimes in long-term field experiments on different soil types     

S. Andersson    M. Simonsson    L. Mattsson    A. C. Edwards  & I. Öborn 《Soil Use and Management》2007,23(1):10-19

Annual potassium (K) balances have been calculated over a 40‐year period for five field experiments located on varying parent materials (from loamy sand to clay) in south and central Sweden. Each experiment consisted of a number of K fertilizer regimes and was divided into two crop rotations, mixed arable/livestock (I) and arable only (II). Annual calculations were based on data for K inputs through manure and fertilizer, and outputs in crop removal. Plots receiving no K fertilizer showed negative K balances which ranged from 30 to 65 kg ha^?1 year^?1 in rotation I, compared with 10–26 kg ha^?1 year^?1 for rotation II. On sandy loam and clay soils, the K yield of nil K plots (rotation I) increased significantly with time during the experimental period indicating increasing release of K from soil minerals, uptake from deeper soil horizons and/or depletion of exchangeable soil K (K_ex). Significant depletion of K_ex in the topsoil was only found in the loamy sand indicating a K supply from internal sources in the sandy loam and clay soils. On silty clay and clay soils, a grass/clover ley K concentration of ～2% (dry weight) was maintained during the 40‐year study period on the nil K plots, but on the sandy loam, loam and loamy sand, herbage concentrations were generally less than 2% K.  相似文献   

IMPACT OF CONTINUOUS SUGAR BEET CROPPING ON POTASSIUM QUANTITY-INTENSITY PARAMETERS IN CALCAREOUS SOILS     

Abbas Samadi 《Journal of plant nutrition》2013,36(8):1154-1167

One hundred-eighteen surface soil samples (59 samples from cultivated areas and 59 samples from virgin soils) were studied to ascertain if potassium (K) quantity-intensity (Q/I) parameters of the soils are being changed by long-term sugar beet cropping. Long-term cultivation resulted in a significant decline in the equilibrium activity ratio (AR_e ^K) values from 0.012 to 0.0047 (moles/L)^1/2 (a drop of 61%) and from 0.013 to 0.008 (a drop of 38%) in Typic calcixerpts and Typic endoaquepts, respectively. Paired t-test revealed that continuous sugar beet cultivation led to significant changes in the easily exchangeable K (ΔK₀) values from ?0.69 to ?0.28 cmol_c/kg (a rise of 59%) the Typic calcixerepts soils. The highest values for PBC^K were associated with the soil types which had the greatest clay contents and smectite clay minerals. Results suggest that continuous sugar beet cropping caused a great decline in K supplying power of the soils.  相似文献   

Dynamics of Potassium in Representative Soil Series of Southwestern Nigeria     

《Communications in Soil Science and Plant Analysis》2012,43(22):3259-3266

Experiments were carried out to evaluate the dynamics of potassium (K) in six representative soil series of southwestern Nigeria to provide guidelines on soil K management. Quantity–intensity (Q/I) approach was used and the Q/I isotherms obtained revealed that all the soils released K before reaching equilibrium, having a negative intercept. The results showed that labile K from the Q/I evaluation was greater than exchangeable K from ammonium–acetate extraction in all the soils, showing that evaluation of soil K by exchangeable K alone may not give an in-depth understanding of the K dynamics in soil. Hence, it should be used in addition to Q/I parameters for a reliable evaluation. The potential buffering capacity obtained ranged from 0.4983 to 1.4272 cmol kg^?1/(mol L^?1)^1/2, indicating that the soils have a low capacity to maintain K concentration for a long period and hence would require frequent K fertilization.  相似文献   

Depletion of Soil Potassium under Exhaustive Cropping in Inceptisol and Alfisol     

《Communications in Soil Science and Plant Analysis》2012,43(1):61-72

Pot-culture studies of intensive cropping without potassium (K) application, taking three successive crops of rice on Sonakhali (Inceptisol) and Ranibundh (Alfisol) soils, revealed that all the forms of soil K declined after the third crop compared to the corresponding initial soil status. A similar trend was also found for nonexchangeable K extracted sequentially and termed as Step K and CR-K (constant rate K). The CR-K contents showed little variations with cropping. Except for the potential buffering capacity of the soil for K at equilibrium (PBC^K ₀) values, all the quantity/intensity (Q/I) parameters, namely activity ratio of potassium (AR^K _e), labile K (–ΔK₀), specifically held K (K_X), and total labile pool of K (K_L) values, decreased in both the soils as they were subjected to repeated cropping. The PBC^K ₀ values changed to a smaller extent in both the soils. In both soils, the threshold levels for release of intermediate K in terms of activity ratio, exchangeable K, and K concentration in soil solution decreased after the third cropping as compared to the initial status. The dry-matter weight of rice, K concentration, and K uptake decreased with the cropping sequence. The difference in values of each parameter between initial status and the third crop was much wider in Inceptisol than in Alfisol.  相似文献   

A Study on the Quantity/Intensity Relationships of Potassium of Sugarcane Growing Soils,Eastern Thailand     

Pitchakorn Suttanukool  Wittaya Jindaluang 《Communications in Soil Science and Plant Analysis》2019,50(2):153-163

Surface and subsurface horizons of 16 representative sugarcane growing soils with varying soil properties in the eastern region of Thailand were collected to determine the potassium (K) fertility status and its availability by using the quantity/intensity relationship (potential buffering capacity of K (PBC_k)). The results showed that most soils had a low K fertility status and lack of reserved K from K-bearing minerals. The PBC_k values of the studied soils ranged from 3.75 to 168 cmol kg^?1/(mol L^?1)^1/2, and the coarse-textured soil group showed much lower PBC_k values; these results suggested a low capability of these soils to replenish K removal by plant uptake compared with that of the fine-textured soil group. The negative delta K (ΔK°) values of the coarse-textured soil group also indicated a large quantity of readily available K for plant uptake that easily leaches at the same time. The higher K activity ratio (AR^k_e) of the coarse-textured soil group (>0.001 mol L^?1)^1/2) than that of the fine-textured soil group (<0.001 mol L^?1)^1/2) suggested that readily available K was desorbed from the non-specific sites of 1:1 clay minerals and specific sites of 2:1 clay minerals, respectively. The ΔK° value of the studied soils was more significantly correlated to K concentration in sugarcane stalks (R² = 0.64) than that of readily available K content (R² = 0.54). Therefore, the results of this study suggested that ΔK° represents a better parameter to estimate K availability in these soils compared to conventional ammonium acetate (NH₄OAc)-extractable K content.  相似文献   

Expression of key enzymes for nitrogen assimilation in grapevine rootstock in response to N‐form and timing     

Carina Paola Lang  Gyngyi Brdos  Nikolaus Merkt  Christian Zrb 《植物养料与土壤学杂志》2020,183(1):91-98

  相似文献