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A laboratory microcosm experiment was conducted to evaluate the effects of the four single-species (Pinus tabulaeformis (Pt), Pinus radiata (Pr), Cercidiphyllum japonicum (Cj), and Ostryopsis davidiana (Od) litters from southwestern China and mixed pine-broadleaf (Pt + Cj, Pr + Cj, Pt + Od, Pr + Od) litters on soil microbial activities and dissolved organic carbon (DOC). Microcosms with the local typical soil and litterbags containing the eight litter types were incubated with 60% water field capacity for 84 days at 20°C. The results showed that the dynamics of soil microbial parameters and DOC were influenced by the litter types with different initial chemical quality. Due to their initial poor nutrient contents, the Pt and Pr litter treatments always showed lower soil microbial activities and DOC at each sampling compared with the Cj and Od litter treatments. However, compared with the single-species pine litter treatments, the inclusion of broadleaf Cj or Od litter into pine litter significantly increased soil microbial activities, and the concentrations of soil DOC during the whole incubation process. The current work thus provided a good implication for plantation management that it should be appropriate to consider Cj as an ameliorative species or retain Od in the pine plantations to improve soil conditions.

Changes in the enzymatic activity of soil variably fertilized with NPKCa were investigated in a field experiment carried out in 2005-2010. The study was conducted with a legume plant, i.e. eastern galega (Galega orientalis Lam.). The experiment was completely randomized and carried out in three replications with the following mineral fertilization: control, N, P, K, NPK, NP, NK, PK, NPKCa, PKCa, Ca, NKCa, and NPCa. Mineral fertilization was applied in kg/ha: (N-20, P-50, K-160, Ca-150). The soil samples collected from the Ap horizon (0-30 cm) of the rhizosphere in spring after the 1^st, 2^nd and 3^rd swathing had a pH_KCl in range from 6.55 to 6.93. The activity of acid phosphatase and alkaline phosphatase was at a low level. The highest activity of urease was recorded in the soil fertilized with NPK, whereas the highest activity of dehydrogenases was in the soil fertilized with PKCa.

The dissipation patterns of thiamethoxam insecticide at two different rates (12.5 and 25 µg/g) in both silty clay loam and loam soils were studied. The half lives of thiamethoxam were in the range of 15.0 to 18.8 days in silty clay loam and 20.1 to 21.5 days in loam soil. The residues of thiamethoxam in potato tubers and soil at harvest time (90 days after planting) could not be detected either in soil or in tubers at any of the applied rates (25 and 50 g a.i./ha). Thus, thiamethoxam does not appear to pose any health hazard to consumers or harm to the environment.

In arid and semiarid regions of northern China, there is an increasing interest in using water-saving superabsorbent polymer (SAP) for field crop production. Experiments were conducted during 2009 and 2010 to study the growth and yield characteristics of summer corn (Zea mays L.) under different (control, 0; low, 10; medium, 20; high, 30 and very high, 40 kg/ha) rates of SAP in a drought-affected field of northern China. Corn yield increased slightly following SAP application at low and medium rate, but significantly at high and very high rates by 22.4 and 27.8%. At the same time, plant height, stem diameter, leaf area, biomass accumulation, harvest index and relative water content as well as protein, sugar and starch contents in the grain increased significantly following SAP treatments. The optimum application of superabsorbent polymer for corn cultivation in the study area would be 30 kg/ha as it best increased the grain yield and quality and maintained higher levels of soil nutrients. Lower rates (10 and20 kg/ha) or higher (≥ 40 kg/ha) rates would neither be sufficient nor economical. We suggest that the application of SAP at 30 kg/ha could be an efficient and economic soil management practice for summer corn production in the drought affected regions of northern China or other areas with similar ecologies.

The research aimed at the assessment of N₂O emission from agricultural soils subject to different fertilization conditions. It was carried out on a long-term experiment field in Skierniewice in Central Poland maintained with no alterations since 1923 under rye monoculture. The treatments included mineral (CaNPK), mineral-organic (CaNPK + M) and organic (Ca + M) fertilization. Measurements were conducted during the growing periods of 2012 and 2013. N₂O emissions from the soil were measured in situ by the means of infrared spectroscopy using a portable FTIR spectrometer Alpha. N₂O fluxes over the measurement periods showed high variability with range 0.13-11.20 g N₂O-N/ha/day (median 2.87, mean 3.16) from mineral treated soil, 0.23-11.06 g N₂O-N/ha/day (median 3.64, mean 3.33) from mineral-organic treated soil and 0.25-12.28 g N₂O-N/ha/day (median 3.14, mean 3.55) from organic treated soil. N₂O fluxes from manure-treated soils were slightly higher than those from soils treated exclusively with mineral fertilizers. N₂O fluxes were positively correlated with soil temperature, air temperature, and content of both, NO₃^- and NH₄⁺, in the soil (0-25 cm) and, to a lesser degree, negatively correlated with soil moisture. Based on the measured N₂O flux and its relationship with environmental factors it can be concluded that both, nitrification and denitrification the are important sources of N₂O in mineral soils of Central Poland, where the average soil water-filled pore space during the growing period range from 22-35%. Under the climate, soil and fertilization conditions in Central Poland, the N₂O emission from cultivated soils during the growing period is approximately estimated as 0.64-0.73 kg N/ha.

The depth of sampling is an important factor for evaluating soil stability. The objective of this study was to test soil aggregate particle-size fractions and soil organic carbon (SOC) in water-stable aggregate by vegetation restoration through 0-60 cm soil profile. We collected soil samples in 30 years old Robinia psendoacacia (Rr); Platycladus orientalis (Po); Pinus tabulaeformis (Pt); abandoned land (Ab), and slope cropland (Sc), which were separated into > 2, 2-1, 1-0.25, 0.25-0.053, and < 0.053 mm fractions. The > 0.25 mm water-stable aggregates (WSA) and mean weight diameter (MWD) were calculated in 0-60 cm soil depth. Results showed that soil aggregate fractions (> 0.25 mm) of four vegetation types were significantly (P < 0.05) higher in 40-60 cm soil depth under Po, Pt, and Ab compared with Sc and the SOC distribution in macro-aggregates (> 0.25 mm) under Rr, Po, Pt, and Ab was higher more than 37.7, 92.4, 92.5, 79.1%, respectively in 40-60 cm compared with Sc additionally, > 0.25 mm WSA and MWD was significantly higher in Pt soil in 20-40 cm, 40-60 cm soil depth (P < 0.05). The results demonstrated that soil stability was enhanced and SOC content was increased after converting slope cropland to forest, especially under Pt forest that greatly influenced the subsoil.

The possibility of sweet sorghum cultivation with different inter-row distances (20, 50, 75 cm) was verified in small scale plots with 3 cultivars (Bovital, Goliath, Sucrosorgho). The maize cv. Atletico (rows 75 cm) was used as a control. The influence of row width and cultivar on fresh and dry biomass, methane and biogas production per area was statistically significant. The methane and biogas production was evaluated in laboratory, via fermentation in Oxi Top Control Merck bottles. Generally, sorghum was more productive than maize. The highest biogas production per hectare was found in case of 25 cm row spacing. Goliath was the most yielding cultivar (in all parameters). The experiment proved possibility to produce biomass from sorghum in narrow rows for biogas stations in the Czech Republic.

The CULTAN (Controlled Uptake Long Term Ammonium Nutrition) system is based on one-time injection of the whole dose of nitrogen required for the vegetation period. The effect of this method on yield and grain quality of winter wheat was observed in a 2-year small-plot trial at 4 different experimental sites in the Czech Republic. The experiment comprised two treatments with the total amount of nitrogen applied during fertilization of 150 kg N/ha. At the CULTAN treatment the whole dose was applied all at once using the GFI 3A injection machine (Maschinen und Antriebstechnik GmbH Güstrow), whereas at the control treatment, the dose was divided into three applications. The average grain yield of winter wheat in 2007 was 9.56 t/ha (control) and 8.78 t/ha (CULTAN); in 2008 it was 9.91 t/ha (control) and 9.63 t/ha (CULTAN). The differences in 2008 were not statistically significant. The contents of nitrogen and gluten were significantly lower at CULTAN treatment in both years. The values of falling number, Zeleny test and bulk density were generally similar at both treatments.

A field study was conducted to study the effectiveness of film-bottomed treatment (FBT) on the seed germination and seedling establishment of Caragana korshinskii Kom. in the arid Hexi Corridor of northwestern China in 2007 and 2008. The experiment involved three different depths of film-bottomed treatments (DFBT) (80, 90 and 100 cm) and a control with twelve replications in each treatment. Soil moisture, seedling emergence percentage, leaf characteristics, shoot height, main root length, basal diameter, biomass, biomass allocation, as well as root system distribution, were studied and were found to be significantly higher with FBT in respect to the check (CK) values. Soil moisture content increased with depths of film-bottomed treatments. Our study demonstrates that C. korshinskii can be grown successfully using FBT in arid areas and 90 cm DFBT gives the maximum growth-promoting effect.

A litterbag experiment was conducted to investigate the changes of tannins and nutrients in branchlets at different decomposition stages of Casuarina equisetifolia in southern subtropical coastal zone, China, using the colorimetric assays. The time required for the loss of half of the initial dry weight (t₅₀) was 9.13 months. Total phenolics (TP), extractable condensed tannins (ECT), protein-bound condensed tannins (PBCT), total condensed tannins (TCT) and protein precipitation capacity (PPC) of branchlets litter decreased rapidly, while fibre-bound condensed tannins (FBCT) increased during decomposition. Nitrogen and phosphorus concentration of the branchlet litter both increased gradually during decay. Negative correlations between TP and nitrogen or phosphorus, as well as TCT and nitrogen or phosphorus were found. These chemical changes enhanced the current knowledge on the potential ecological role of nutrient transformation in tannins in C. equisetifolia plantations.

The aim of this work is to evaluate the changes of Mehlich 3 - P, K, Ca and Mg contents in soil during a long-term field experiments with sewage sludge, farmyard manure (FYM) and mineral NPK (NPK) application, compared to the control non-fertilized treatment. The experiment was established at the Humpolec and Suchdol sites (Czech Republic). Potatoes, wheat and barley were grown in crop rotation. Fertilizing system was based on the same nitrogen dose of 330 kg N/ha per one crop rotation. Archive soil samples from the beginning of the experiment (1996) and from the end of each year's crop rotation (1999, 2002, 2005, 2008 and 2011) were analyzed. In spite of the different soil-climatic conditions of the studied sites, very similar tendencies of P, K, Ca and Mg contents changes after the fertilizing systems used were observed in the soil. In case of the same nitrogen dose (330 kg N/ha), sewage sludge appeared to be better source of bioavailable soil phosphorus compared to the farmyard manure and NPK. On the contrary, FYM was a better source of bioavailable potassium and magnesium, despite the lower total magnesium content in FYM. The NPK treatment was the best long-term source of bioavailable potassium.

To assess the effects of long-term fertilization on soil available micronutrients in farmland, this study examined diethylenetriaminepentaacetic acid (DTPA) extractable iron (Fe), manganese (Mn), copper (Cu), and zinc (Zn) in surface soil with monoculture of corn (Zea mays L.) with a 30-year filed fertilization experiment established in Northeast China. Treatments included no fertilization (CK); nitrogen only (N); nitrogen and phosphorus only (NP); NP and potassium (NPK); NPK plus cornstalk (SNPK), and NPK plus farmyard manure (MNPK). Results showed that DTPA-Fe and Mn were significantly increased with chemical N application, and DTPA-Cu and Zn were significantly increased with farmyard manure amendment, while micronutrients were not significantly different between treatment SNPK and CK. DTPA-Fe and Mn were about twice to threefold in treatments N, NP, and NPK as much as in treatments SNPK, MNPK and CK. DTPA-Cu and Zn in treatment MNPK were about 3.9 and 6.5 times as much as in CK. DTPA-Fe and Mn decreased with the increasing of soil pH and cation exchange capacity, while DTPA-Cu and Zn increased with the increase of soil organic carbon and electrical conductivity.

The effects of phosphorus (P) fertilizer on P loss potential, soil Olsen-P and neutral phosphatase activities in paddy soils fertilized with superphosphate or pig manure (PM) were evaluated in this paper. Data were collected from a field experiment in the Tai Lake Basin, China. Superphosphate rates were 0, 17.5, 26.7, and 35.0 kg P/ha, and PM rates were 0, 1.4, 2.1, and 2.8 t/ha for each crop, respectively. Soil Olsen-P in the plow layer increased to a greater extent with PM than with superphosphate. Pig manure increased neutral phosphatase activities in the plow layer compared with PM-free treatment. In contrast, superphosphate inhibited neutral phosphatase activities compared with superphosphate-free treatment. Spring application of P fertilizer markedly increased the total P of surface water in November (< 0.01 vs. 0.10 mg/L) compared with P-free treatment. The total P of shallow groundwater at a 75 cm depth was ~0.01 mg/L. Phosphorus fertilizer did not influence Olsen-P or neutral phosphatase activities under the plow layer. Downward movement of P did not occur. Appropriate rate of P application of 26.2 kg P/ha for each crop in this soil reduced the risk of P loss in the paddy wetland ecosystem.

Chicory (Cichorium intybus L.) is a rich source of polysaccharides (intibin and inulin), vitamins, acids and mineral salts. The present studies determined the antagonistic activity of selected bacteria of the soil environment of root chicory towards fungi pathogenic towards this plant: Alternaria alternata, Botrytis cinerea, Fusarium culmorum, F. oxysporum, Thanatephorus cucumeris and Sclerotinia sclerotiorum. Root chicory was cultivated with using cover crops (oats, tansy phacelia and common vetch). The use of cover crops, especially oats, in the cultivation of root chicory had a positive effect both on the total population of bacteria and the population of Bacillus spp. and Pseudomonas spp. in the soil. Antagonistic Bacillus spp. and Pseudomonas spp. displayed differentiated activity towards the studied fungi. The greatest antagonistic effect was found out after the mulch of oats. After common vetch, the antagonistic activity of bacteria was more than twice, and after phacelia three times as low as after oats. In the traditional cultivation of root chicory this activity was nearly twelve times lower.

The experiments were conducted in four locations in Serbia: Valjevo, Kucevo, Nova Pazova and Surduk in 2012 and 2013. A working hypothesis that growing conditions would not affect the rutin content in buckwheat leaves was set up. The content of rutin in leaves of buckwheat was determined by the HPLC/DAD technique, using the external standard calibration method. Out of the basic biometric parameters, average value, variance, and the variation coefficient were estimated. Results were processed by the analysis of variance for the factorial experiment. The analysis of variance showed existence of significant differences in the rutin content, over locations, but only in the first year of testing. The average content of rutin in the first and the second year was 3.30% and 2.61%, respectively, and in both years of testing it amounted on average to 2.82%. The variation in the rutin content was larger in the second year of testing. On the other hand, this variation was lower in the first year (5.3-29.0%) in comparison to the second year (16.2-28.6%). Relatively lower rutin contents were recorded in samples collected at lower-altitude locations.

Cattle slurry is frequently used fertilizer on grasslands, but little is known about its effect on plant species composition. The aim of this study was therefore to assess effect of different application rates of cattle slurry (S0 - 0, S1 - 60, S2 - 120, S3 - 180, S4 - 240 kg N/ha/year) on the plant species composition of three-cut grassland. The study was performed over 6 years on moderately moist upland Arrhenatherion grassland in the Czech Republic dominated by Alopecurus pratensis, Trisetum flavescens, and Poa spp. Species composition recorded in treatments with application of cattle slurry in rate up to 120 kg N/ha/year was similar to the unfertilized control. During first three years, species richness was similar in all treatments and then decreased the most in S4 followed by S3 treatment. Cover of short forbs increased in S0 and decreased with an increase in slurry application rate which supported tall grasses. Application of cattle slurry up to 120 kg N/ha/year can be considered as suitable compromise between maintenance of species rich grasslands and requirements of farmers for sufficient forage production.

Wheat grain products are the primary source of dietary Cd-intake for humans. Since varieties differ markedly in grain-Cd accumulation, efforts are needed to find traits associated with low, or high, accumulation. Two durum wheat varieties, selected in a field screening as low (Creso) and high (Svevo) grain-Cd accumulating, were grown on soil spiked with 1.5, 3 and 4.5 mg Cd/kg. Growth patterns, Cd uptake and translocation were investigated at heading and maturity. Cadmium did not affect plant growth and grain yield, but grain-Cd concentration always exceeded the permissible limit of 0.2 mg Cd/kg, and was approximately double in Svevo than in Creso. At maturity, total Cd-uptake increased linearly with supply in Creso, from 13 to 23 µg/plant, and was approximately 18 µg/plant, irrespective of Cd level, in Svevo. Partitioning to shoot was higher in Svevo than in Creso, both at heading and maturity. We suggest that reduced plant height, high root to shoot biomass ratio during vegetative growth and elevated post-heading dry matter accumulation promoted Cd accumulation into grain. Since these traits are common to modern wheat varieties, risks of grain Cd-contamination can increase in the future.

The aim of study was to compare the effect of farming methods on soil microbial communities and dehydrogenase activity (DHA). During 2008-2013, in the five-field crop rotation the following treatments were carried out: ORG - organic; ORGFYM - organic with cattle manure; CONFYM - conventional (cattle manure, mineral fertilizers and pesticides were used). From the treatments soil samples in three replicates were taken for microbiological tests in September yearly. Total bacteria and cellulose decomposing bacteria were determined as a number of colony forming units per g of dry soil. Soil DHA was determined in accordance with Tabatabai (1982). Solid cattle manure applied in the ORGFYM rotation increased significantly (P < 0.05) the number of total bacteria and cellulose decomposing bacteria (by 19.4% and 45.3%, respectively), and DHA by 22.7%. There appeared no clear and significant differences in effects between ORGFYM and CONFYM treatments, as an average of experiment period. In some cases, the use of certain pesticides in CONFYM treatment significantly affected the microbe numbers and soil DHA.

The aim of this study was to determine the effect of sulphur (S) fertilization on macronutrient concentrations in the roots, straw and oil cake of white mustard and Indian mustard. The experiment was conducted in northeastern Poland (2006-2008). The highest content of N, P, K, Mg and S was noted in the oil cake of both mustard species. Sulphur fertilization increased S concentrations and had no effect on Mg concentrations in the roots of white mustard and Indian mustard. Sulphur fertilizers applied to soil significantly increased the content of N, K and Ca in the roots of Indian mustard, whereas they had no significant effect on the content of N, P and Ca, and decreased K concentrations in the roots of white mustard. Sulphur fertilization led to a significant decrease in N content, and an increase in the content of K and Ca in the straw of both mustard species. Sulphur fertilization significantly decreased P concentrations and increased S concentrations in the oil cake of both mustard species. In response to S fertilization, the content of N and K decreased in the oil cake of Indian mustard, but did not change significantly in the oil cake of white mustard. Therefore, S fertilization significantly differentiated the fertilizing value of post-harvest residues and the feeding value of white mustard and Indian mustard seeds.

The aim was to compare the efficacy, selectivity to sunflower and dissipation of three chloracetamide herbicides (acetochlor, metolachlor and pethoxamid) in dependence on precipitation after application. A small plot field trial was carried out with sunflower in Central Bohemia in 2010 and 2011. The remaining concentration of active ingredient in the soil of all studied herbicides was lower in the year with a higher temperature and a low level of total natural precipitation at the beginning of the growing season. Higher leaching of metolachlor and pethoxamid was recorded in irrigated plots. No leaching was found in the case of acetochlor. The highest leaching was found for metolachlor (9.2-25.5% in soil layer 5-10 cm). The highest phytotoxicity was found for acetochlor (9.8%) > pethox-amid (4.6%) > metolachlor (1.8%). The mean phytotoxicity in the irrigated plots was 6.9%, compared with 3.9% in the non-irrigated plots. The efficacy of the tested herbicide was affected by wet conditions. The highest efficacy on Chenopodium album, Amaranthus retroflexus, Echinochloa crus-galli and Solanum physalifolium was recorded after application of acetochlor and irrigation.

The effect of mineral nitrogen (N) nutrition on seed production and acquisition of ¹⁵N from fertilizers by components of cereal-pea mixtures was investigated. Yields of wheat-pea and oats-pea mixtures raised together with the increase of cereals percentage in the pot, and higher seed yields of mixture with barley was affected by a larger share of pea plants. The percentage of nitrogen derived from fertilizers was significantly higher in cereals as compared with pea. Pea accumulated the greatest quantity of nitrogen from fertilizers in straw and roots, and cereals translocated ¹⁵N mainly to ears - grain and glumes with rachis. The percentage of ¹⁵N in seeds of pea amounted to 15% on the average, and in grain of cereals - 54% to 60% of the total N taken up.

We conducted field experiments since 2006 to determine the effect of tillage practices and rate of nitrogen fertilization on soil properties and crop yield. Four tillage practices and five N rates were used. The results showed that the year-round total yield of wheat and maize under harrow tillage (HT) and rotary tillage (RT) was not significantly different from that of conventional tillage (CT, moldboard tillage) but was higher than that of no-tillage (NT). Reduced tillage (HT and RT) with straw returned and rate of nitrogen (157.5 kg/ha for wheat and 202.5 kg/ha N for maize) were suitable to increase the yield and adjust the soil carbon and nitrogen situation for the winter wheat-summer maize cropping system.

The aeroponic system is a viable technological alternative for potato minituber production within a potato tuber seed system. The aim of the study was to evaluate the productivity of potato minitubers grown in aeroponic culture and collected in 14 successive periods of the growing season. The minitubers of cvs. Ametyst and Tajfun were tested in an experimental field after a storage period. It was found that cv. Ametyst was characterized by higher yield and number of tubers than cv. Tajfun. Yield of cv. Ametyst averaged 42.6 t/ha, and cv. Tajfun 37.3 t/ha. The number of tubers over 3 cm of cv. Ametyst averaged 644.2 per ha, and cv. Tajfun 437.7 per ha. The yield and number of tubers was dependent on the physiological age of minitubers harvested on successive dates. Comparing the productivity of minitubers grown in aeroponics and in the soil, a significant difference was found in the number of tubers with a transversal diameter over 3 cm. There were more daughter tubers from minitubers grown in soil. They are the result of different-size minitubers used for planting, smaller ones from aeroponics and larger from soil.

To investigate the effect of fertilization practice on dissolved organic nitrogen (DON) in aggregates, the study was conducted and involved four fertilization treatments: no fertilizer; mineral fertilizer (MF); pig manure matched with mineral fertilizer (MFP) and crop straw matched with mineral fertilizer (MFR). The results showed that DON content and storage were the highest in > 5 mm aggregates and were the lowest in < 0.25 mm aggregates. Compared with MF, MFP and MFR significantly increased DON contents in > 5 mm by 404.7% and 184.4%. In comparison with MFR, DON content and storage in > 5 mm aggregates for MFP were significantly enhanced by 77.5% and 75.0%. A significantly positive linear correlation relationship between DON content and microbial biomass carbon content was observed in aggregates (R² = 0.84; P < 0.01). The results suggest that pig manure matched with mineral fertilizer is a preferred strategy for retaining DON nutrient due to enhanced microbial biomass in aggregates on sloping upland of purple soil.

The study should reveal the effects of soil texture and of seed characteristics of oilseed rape (Brassica napus L.) on seed survival in the soil by a burial experiment. Seeds of 58 conventional and new trait accessions (genetically modified and/or with altered seed ingredients) were buried for six months in sandy loam (SL), clay (c) or silty clay loam (SICL) in the seasons 2008/2009 and 2009/2010 in Germany. Between 84-93% (2008/2009) and 64-87% (2009/2010) of the conventional seeds survived in the soil, and so did 41-67% and 8-44% of the new trait seeds. Significantly more seeds were found in C and SICL compared to SL. Seed survival also significantly depended on the genotype, with high and low seed survival in both conventional and new trait accessions. Seed survival rates are probably linked with moisture and oxygen provided by different soils. As soils with good water storage conditions seem to have a higher probability for oilseed rape seeds from harvest losses to survive, other measures such as growing low dormancy varieties and proper soil tillage are especially relevant to avoid volunteers on these soils.

This study aimed to separate the respective contributions of root and microbial respiration to soil respiration in a rape field in Southwest China. The soil respiration was measured with a closed chamber technique and a regression method was used to apportion root and microbial respiration. Microbial and root respiration ranged from 70.67 to 183.77 mg CO₂/m²/h and 21.99 to 193.09 mg CO₂/m²/h, averaged 127.16 and 116.66 mg CO₂/m²/h during the rape growing season, respectively. Root respiration coefficient ranged from 0.41 to 5.39 mg C-CO₂/g C/h and was negatively correlated with root/shoot ratio, aboveground and belowground biomass, but positively correlated with root N content. The contribution of root respiration to soil respiration averaged 44.2%, ranging from 14.5% to 62.62%.

Paddy rice is one of the most important cereal crops in China. Nitrogen (N) is closely related to crops production by influencing the photosynthetic efficiency of paddy rice. In this study, laser-induced fluorescence (LIF) technology with the help of principal component analysis (PCA) and back-propagation neural network (BPNN) is proposed to monitor leaf N content (LNC) of paddy rice. The PCA is utilized to extract the characteristic variables of LIF spectra by analysing the major attributes. The results showed that the first three principal components (PCs) can explain 95.76% and 93.53% of the total variance contained in the fluorescence spectra for tillering stage and shooting stage, respectively. Then, BPNN was utilized to inverse the LNC on the basis of the first three PCs as input variables and can obtain the satisfactory inversion results (R² of tillering stage and shooting stage are 0.952 and 0.931, respectively; residual main range from -0.2 to 0.2 mg/g). The experimental results demonstrated that LIF technique combined with multivariate analysis will be a useful method for monitoring the LNC of paddy rice, which can provide consultations for the decision-making of peasants in their N fertilization strategies.

In Central Slovenia within a long term static experiment IOSDV we investigated the impact of mineral nitrogen (N) fertilisation (0, 65, 130, 195 kg/ha) on the N content and the N amount in winter wheat (larger roots, stems, spikes and leaves) in EC 81/82 and EC 90/91, employing three systems of management: farmyard manure ploughing in before forecrop maize, straw ploughing in and green manure, no organic fertilisation. At EC 81/82 the N content in larger roots was around twice as high as the N content in stems and around twice as low as the N content in spikes and leaves. There was 80% of the whole N amount in plant located in the spikes and leaves (33-168 kg/ha) in EC 81/82 and 90% in EC 90/91. Calculated N recovery from mineral fertiliser was 68-87%; it increased with the increasing N rates in the system with farmyard manure ploughing in and in the system with no organic fertilisation, but not in the system with straw ploughing in and green manure. Between EC 81/82 and EC 90/91 wheat gained from 4 to 34 kg N/ha, but there were more important translocations of N inside the plants, which were higher at higher mineral N rates. There was a significant impact of management system on the N uptake at the highest mineral N rate.

How light conditions affect development of park grasslands is a question that has not been satisfactory addressed. The aim of this study was therefore determination of the level to which unfavorable light conditions influence grassy parks area and relationships between parameters which determine state of turf grasses. Researches were conducted in two parks in Warsaw, in various light conditions and included measurement of: leaf density, sward height, leaf area index (LAI), and botanical composition of the communities. The leaf density of shaded areas did not exceed 70%. LAI value varied from 0.5 to 0.9-fold lower than in the areas in half-shade and in sun. The participation of basic lawn species at Skaryszewski Park was higher under shade, while at Łazienki Królewskie was higher in full-sunlight areas. The state of tested grassy areas in limited solar radiation does not satisfy the requirements of recreational and representational functions. The development processes of vegetation coverage were inhibited at the sites of lower solar radiation. LAI was influenced by both leaf coverage and sward height. Agrostis stolonifera and Poa trivialis may be recommended to create grass areas under limited solar radiation.