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Sample records for hungarian long-term fertilizer

  1. Effect of long-term fertilization on soil nitrate distribution

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A thirteen years long-term field fertilizer experiment was conducted to monitor the effect of different fertilization on soil nitrate distribution. The results showed: (1) Applying relative excessive N fertilizer could result large quantities of NO3- residue and NO3- movement downward in soil profiles; amending phosphate fertilizer or organic manure with nitrogen fertilizer together could significantly improve the status of NO3- leaching downward due to the balanced uptake of nutrients by crops. (2) Appropriate amounts of nitrogen fertilizer which was equal or smaller than the optimal fertilization rate could not result in more NO3- leaching in Northern China. (3) Precipitation influenced the amounts and depth of soil NO3- leaching: NO3- could move to 80 cm depth or below at autumn or at the next spring when rainfall was higher during the rainy season through July to September in North China.

  2. Long-term fate of nitrate fertilizer in agricultural soils.

    Science.gov (United States)

    Sebilo, Mathieu; Mayer, Bernhard; Nicolardot, Bernard; Pinay, Gilles; Mariotti, André

    2013-11-05

    Increasing diffuse nitrate loading of surface waters and groundwater has emerged as a major problem in many agricultural areas of the world, resulting in contamination of drinking water resources in aquifers as well as eutrophication of freshwaters and coastal marine ecosystems. Although empirical correlations between application rates of N fertilizers to agricultural soils and nitrate contamination of adjacent hydrological systems have been demonstrated, the transit times of fertilizer N in the pedosphere-hydrosphere system are poorly understood. We investigated the fate of isotopically labeled nitrogen fertilizers in a three-decade-long in situ tracer experiment that quantified not only fertilizer N uptake by plants and retention in soils, but also determined to which extent and over which time periods fertilizer N stored in soil organic matter is rereleased for either uptake in crops or export into the hydrosphere. We found that 61-65% of the applied fertilizers N were taken up by plants, whereas 12-15% of the labeled fertilizer N were still residing in the soil organic matter more than a quarter century after tracer application. Between 8-12% of the applied fertilizer had leaked toward the hydrosphere during the 30-y observation period. We predict that additional exports of (15)N-labeled nitrate from the tracer application in 1982 toward the hydrosphere will continue for at least another five decades. Therefore, attempts to reduce agricultural nitrate contamination of aquatic systems must consider the long-term legacy of past applications of synthetic fertilizers in agricultural systems and the nitrogen retention capacity of agricultural soils.

  3. [Variations of soil fertility level in red soil region under long-term fertilization].

    Science.gov (United States)

    Yu, Han-qing; Xu, Ming-gang; Lü, Jia-long; Bao, Yao-xian; Sun, Nan; Gao, Ju-sheng

    2010-07-01

    Based on the long-term (1982-2007) field experiment of "anthropogenic mellowing of raw soil" at the Qiyang red soil experimental station under Chinese Academy of Agricultural Sciences, and by using numerical theory, this paper studied the variations of the fertility level of granite red soil, quaternary red soil, and purple sandy shale soil under six fertilization patterns. The fertilization patterns included non-fertilization (CK), straw-returning without fertilizers (CKR), chemical fertilization (NPK), NPK plus straw-return (NPKR), rice straw application (M), and M plus straw-return (MR). The soil integrated fertility index (IFI) was significantly positively correlated with relative crop yield, and could better indicate soil fertility level. The IFI values of the three soils all were in the order of NPK, NPKR > M, MR > CK, CKR, with the highest value in treatment NPKR (0.77, 0.71, and 0.71 for granite red soil, quaternary red soil, and purple sandy shale soil, respectively). Comparing with that in the treatments of no straw-return, the IFI value in the treatments of straw return was increased by 6.72%-18.83%. A turning point of the IFI for all the three soils was observed at about 7 years of anthropogenic mellowing, and the annual increasing rate of the IFI was in the sequence of purple sandy shale soil (0.016 a(-1)) > quaternary red clay soil (0.011 a(-1)) > granite red soil (0.006 a(-1)). It was suggested that a combined application of organic and chemical fertilizers and/or straw return could be an effective and fast measure to enhance the soil fertility level in red soil region.

  4. Short- and long-term effects of unemployment on fertility.

    Science.gov (United States)

    Currie, Janet; Schwandt, Hannes

    2014-10-14

    Scholars have been examining the relationship between fertility and unemployment for more than a century. Most studies find that fertility falls with unemployment in the short run, but it is not known whether these negative effects persist, because women simply may postpone childbearing to better economic times. Using more than 140 million US birth records for the period 1975-2010, we analyze both the short- and long-run effects of unemployment on fertility. We follow fixed cohorts of US-born women defined by their own state and year of birth, and relate their fertility to the unemployment rate experienced by each cohort at different ages. We focus on conceptions that result in a live birth. We find that women in their early 20s are most affected by high unemployment rates in the short run and that the negative effects on fertility grow over time. A one percentage point increase in the average unemployment rate experienced between the ages of 20 and 24 reduces the short-run fertility of women in this age range by six conceptions per 1,000 women. When we follow these women to age 40, we find that a one percentage point increase in the unemployment rate experienced at ages 20-24 leads to an overall loss of 14.2 conceptions. This long-run effect is driven largely by women who remain childless and thus do not have either first births or higher-order births.

  5. Long-term Green Innovation Opportunities Within the Hungarian District Heating Sector Towards 2030

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    Horvath Balint

    2016-07-01

    Full Text Available Natural gas is still the primary input of the Hungarian heating and cooling systems, therefore it still makes most of the overheads. One of the main obstacles of a competitive district heating system is the public opinion which still considers this service more expensive than the traditional heating forms. According to the absolute numbers this assumption might be valid but from a more accurate economic perspective, heat production has more aspects to stress. Most people forget about the simple fact that the maintenance costs of natural gas based systems are rather outsourced to the consumer than in the case of district heating. Furthermore, the uneven rate of the fixed and variable costs of this technology does not prove to be optimal for service developments. Investigating the future tendencies highlight that encouraging the efficiency improvement of district heating and the spread of technological innovation in the sector does not belong to the top priorities. Still, avoiding this problem it could lead serious deadweight losses in the case of the heating sector.

  6. Influence of long-term fertilization on soil enzyme activities

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    Alina Dora SAMUEL

    2009-05-01

    Full Text Available Soil enzyme activities (actual and potential dehydrogenase, catalase, acid and alkaline phosphatase were determined in the 0–10, 10–20, and 20–30 cm layers of a brown luvic soil submitted to a complex fertilization experiment with different types of green manure. It was found that each activity decreased with increasing sampling depth. It should be emphasized that greenmanuring of maize led to a significant increase in each of the five enzymatic activities determined. The enzymatic indicators of soil quality calculated from the values of enzymatic activities showed the order: lupinus + rape + oat > lupinus > vetch + oat + ryegrass > lupinus + oat + vetch > unfertilized plot. This order means that by determination of enzymatic activities valuable information can be obtained regarding fertility status of soils. There were significant correlations of soil enzyme activities with chemical properties.

  7. Long-term organic fertilization effect on chernozem structure

    Science.gov (United States)

    Słowińska-Jurkiewicz, A.; Bryk, M.; Medvedev, V. V.

    2013-01-01

    The objective of the study was to examine the structure of typical Ukrainian chernozem developed on loess, which (I) had been fertilized by standard crop rotation since 1912 with farm yard manure at the rate of 16 t ha-1 and (II) had not been fertilized with farm yard manure by sugar beet monoculture since 1929. After harvest of winter wheat and sugar beet, the samples of undisturbed structure were taken from 5 layers of both profiles: 0-8, 10-18, 20-28, 30-38, and 40-48 cm. The morphological analysis of the structure of the investigated chernozem revealed that the most visible differences between the soil structures of the two pedons occurred in their superficial layers. The 0-18 cm layer of the soil in the experiment I had an aggregate structure, whereas analogous layer of the soil in experiment II was much more compacted. Below about 30 cm from the ground level both pedons had very similar structure. For the soil in the experiment I an appropriate crop rotation and regular supplies of organic matter allowed for preservation of a favourable structure even in the upper layers - in contrast to the soil in the experiment II.

  8. [Variation characteristics of maize yield and fertilizer utilization rate on an upland yellow soil under long term fertilization].

    Science.gov (United States)

    Luo, Long-Zao; Li, Yu; Zhang, Wen-An; Xiao, Hou-Jun; Jiang, Tai-Ming

    2013-10-01

    An analysis was made on the 16-year experimental data from the long term fertilization, experiment of maize on a yellow soil in Guizhou of Southwest China. Four treatments, i. e. , no fertilization (CK), chemical fertilization (165 kg N x hm(-2), 82.5 kg P2O5 x hm(-2), and 82.5 kg K2O x hm(-2), NPK), organic manure (30555 kg x hm(-2), M), and combined applicatioin of chemical fertilizers and organic manure (NPKM), were selected to analyze the variation trends of maize yield and fertilizer use efficiency on yellow soil under effects of different long term fertilization modes, aimed to provide references for evaluating and establishing long term fertilization mode and promote the sustainable development of crop production. Overall, the maize yield under long term fertilization had an increasing trend, with a large annual variation. Treatment NPKM had the best yield-increasing effect, with the maize yield increased by 4075.71 kg x hm(-2) and the increment being up to 139.2%. Long term fertilization increased the fertilizer utilization efficiency of maize. In treatment M, the nitrogen and phosphorus utilization rates were increased significantly by 35.4% and 18.8%, respectively. Treatment NPK had obvious effect in improving potassium utilization rate, with an increment of 20% and being far higher than that in treatments M (8.7%) and NPKM (9.2%). The results showed that long term fertilization, especially the combined application of chemical fertilizers and organic manure, was of great importance in increasing crop yield and fertilizer use efficiency.

  9. The long-term effect of the timing of fertility decline on population size

    NARCIS (Netherlands)

    O'Neill, BC; Scherbov, S; Lutz, W

    1999-01-01

    Existing long-range population projections imply that the timing of the fertility transition has a relatively unimportant effect on long-term population size when compared with the impact of the level at which fertility is assumed eventually to stabilize. However, this note shows that the effect of

  10. The long-term effect of the timing of fertility decline on population size

    NARCIS (Netherlands)

    O'Neill, BC; Scherbov, S; Lutz, W

    1999-01-01

    Existing long-range population projections imply that the timing of the fertility transition has a relatively unimportant effect on long-term population size when compared with the impact of the level at which fertility is assumed eventually to stabilize. However, this note shows that the effect of

  11. [Humus composition and stable carbon isotope natural abundance in paddy soil under long-term fertilization].

    Science.gov (United States)

    Ma, Li; Yang, Lin-Zhang; Ci, En; Wang, Yan; Yin, Shi-Xue; Shen, Ming-Xing

    2008-09-01

    Soil samples were collected from an experimental paddy field with long-term (26 years) fertilization in Taihu Lake region of Jiangsu Province to study the effects of different fertilization on the organic carbon distribution and stable carbon isotope natural abundance (delta 13C) in the soil profile, and on the humus composition. The results showed that long-term fertilization increased the organic carbon content in top soil significantly, and there was a significantly negative exponential correlation between soil organic carbon content and soil depth (P humus (humin) was the main humus composition in the soil, occupying 50% or more, and the rest were loosely and stably combined humus. Long-term fertilization increased the content of loosely combined humus and the ratio of humic acid (HA) to fulvic acid (FA).

  12. SOIL AGROCHEMICAL PROPERTIES IMPROVEMENT IN LONG TERM FIELD EXPERIMENT WITH FERTILIZERS

    Directory of Open Access Journals (Sweden)

    Mihaela Lungu

    2005-10-01

    Full Text Available Soil fertility is studied in long-term field experiments. Researches are carried out in several agricultural research stations, out of which the following have been chosen for the present paper: Albic Luvisol* at Albota; Haplic Phaeozem at Fundulea; Chromic Luvisol at Şimnic; Calcic Chernozem at Secuieni; and Haplic Chernozem at Podu Iloaiei. Long term fertilization with nitrogen and phosphorus generally improved the soil agrochemical properties. The evolution of organic matter, nitrogen, mobile phosphorus and potassium, and mobile microelements contents were studied, using the standardized method used in the ICPA laboratories. The organic matter and total nitrogen contents didn’t change significantly under the nitrogen and phosphorus long-term fertilization influence. The mobile phosphorus contents have the tendency to grow very significantly with the growth of phosphorus fertilizers. At the same time, slight depletions of these contents are registered as the high nitrogen doses from fertilizers stimulate plant growth and, obviously, nutritive elements absorption. Mobile potassium contents changes very little, with insignificant differences. Significant depletions are registered only with high fertilizers doses, due to the stimulation of the nutritive elements absorption in plants. Microelements contents don’t change almost at all. They are within the normal content limits and no excess or deficiency was registered, in any of the studied stations. For the agricultural practice, economical studies are recommended, about how high fertilizing expenses are covered by the yield growth. Not the least, production quality study in different variants of mineral fertilization could prove interesting.

  13. Phosphorus Changes and Sorption Characteristics in a Calcareous Soil Under Long-Term Fertilization

    Institute of Scientific and Technical Information of China (English)

    GUO Sheng-Li; DANG Ting-Hui; HAO Ming-De

    2008-01-01

    Knowledge of phosphorus (P) behavior in long-term fertilized soils is essential for programming fertilization practices and for sustaining environmental quality.The long-term (1984-1997) effects of various fertilization treatments on P changes and sorption isotherms as well as the relationship of soil properties to P sorption and P forms were evaluated in an Ustic Isohumisol,a calcareous soil,on the Loess Plateau,China.Compared to 1984,after 13 years of crop production,total soil P in the no-P treatments (control and N treatment) decreased by 5%-7%,but in the phosphorus fertilizer alone (P),nitrogen and phosphorus fertilizers in combination (NP),manure alone (M),and nitrogen and phosphorus fertilizers and manure in combination (NPM) treatments,it increased by 22%,19%,28%,and 58%,respectively.Residual fertilizer P was found mainly in NH4Ac-soluble P (Cas-P),followed by NaHCO3-sohible P (NaHCO3-P),and NH4F-soluble P (Al-P).Phosphorus sorption in the soils with different fertilization practices fit the Langmuir equations.Phosphorus sorption capacity in the no-P treatments increased,whereas it decreased in the P-included treatments (P,NP,and NPM treatments).Phosphorus sorption maximum (Qm) was significantly and negatively correlated to inorganic P including Na4CO3-P,Cas-P,NaOH-Na2CO3-soluble P (Fe-P),and AI-P (P ≤ 0.01).Moreover,long-term fertilization increased soil organic carbon in the NP,M,and NPM treatments and decreased pH in the NP and NPM treatments.Thus,the ability of the soil to release sorbed P to the environment increased under long-term P fertilization.

  14. Differences in chemical composition of soil organic carbon resulting from long-term fertilization strategies.

    Science.gov (United States)

    Li, Zengqiang; Zhao, Bingzi; Wang, Qingyun; Cao, Xiaoyan; Zhang, Jiabao

    2015-01-01

    Chemical composition of soil organic carbon (SOC) is central to soil fertility. We hypothesize that change in SOC content resulting from various long-term fertilization strategies accompanies the shift in SOC chemical structure. This study examined the effect of fertilization strategies along with the time of fertilizer application on the SOC composition by 13C nuclear magnetic resonance (NMR) spectroscopy. The soils (Aquic Inceptisol) subjected to seven fertilizer treatments were collected in 1989, 1999 and 2009, representing 0, 10 and 20 years of fertilization, respectively. The seven fertilizer treatments were (1-3) balanced fertilization with application of nitrogen (N), phosphorus (P) and potassium (K) including organic compost (OM), half organic compost plus half chemical fertilizer (1/2OM), and pure chemical NPK fertilizer (NPK); (4-6) unbalanced chemical fertilization without application of one of the major elements including NP fertilizer (NP), PK fertilizer (PK), and NK fertilizer (NK); and (7) an unamended control (CK). The SOC content in the balanced fertilization treatments were 2.3-52.6% and 9.4-64.6% higher than in the unbalanced fertilization/CK treatments in 1999 and 2009, respectively, indicating significant differences in SOC content with time of fertilizer application between the two treatment groups. There was a significantly greater proportion of O-alkyl C and a lower proportion of aromatic C in the balanced fertilization than in unbalanced fertilization/CK treatments in 1999, but not in 2009, because their proportions in the former treatments approached the latter in 2009. Principal component analysis further showed that the C functional groups from various fertilization strategies tended to become compositionally similar with time. The results suggest that a shift in SOC chemical composition may be firstly dominated by fertilization strategies, followed by fertilization duration.

  15. Nitrogen budget in agroecosystems on gray forest soils under long-term fertilization

    Science.gov (United States)

    Nikitishen, V. I.; Lichko, V. I.

    2008-04-01

    Long-term stationary field experiments were performed to study the efficiency of increased rates of nitrogen fertilizer in crop rotations with cereal crops, perennial grasses, clover, and plow fallow on gray forest soils. It was found that an excess of mineral nitrogen (mainly of nitrates) accumulated in the soil in the case of unbalanced nitrogen fertilization and long-term fallowing creates conditions for the development of unfavorable processes in the nitrogen cycle. Significantly increasing nitrogen losses from the agroecosystem because of leaching and denitrification constitute a depletion hazard for the soil nitrogen pool.

  16. Phosphorus speciation of clay fractions from long-term fertility experiments in Sweden

    OpenAIRE

    Eriksson, Ann Kristin; Gustafsson, Jon Petter; Hesterberg, Dean

    2015-01-01

    Phosphorus (P) losses from agricultural soils constitute a main driver for eutrophication of the Baltic Sea. There is limited knowledge about sorption and release processes of P in these soils, especially concerning the effects of fertilization. In this study, P speciation of the clay fractions from six different soils in long-term fertility experiments in Sweden was investigated by P K-edge XANES spectroscopy. As expected, unfertilized soils had lower concentrations of acid-digestible P comp...

  17. Impact of Long-Term Fertilization on Cropland Soil Fauna Community at Loess Soil, Shannxi, China

    Institute of Scientific and Technical Information of China (English)

    LIN Ying-hua; YANG Xue-yun; ZHANG Fu-dao; GU Qiao-zhen; SUN Ben-hua; MA Lu-jun

    2005-01-01

    The relationship between long-term fertilization and cropland soil fauna was studied at the station's experiment research network for soil fertility and fertilizers in Loess soil of Shannxi Provincefrom Jul. 2001 to Oct. 2002. Six types of long-term fertilizer were carried out for this study including non-fertilizer (CK), abandonment (ABAND), nitrogenous and phosphors and potassium fertilizers combined (NPK), straw and NPK (SNPK), organic material and NPK (MNPK) and 1.5 times MNPK (1.5MNPK). 72 soil samples were collected and 5 495 species of cropland soil fauna obtained by handsorting and Cobb methods at 4 times, belonging to 6 Phyla, 11 Classes, 22 Orders, 2 Superfamilies, 61 Families and 35 Genera. The result showed that different fertilizer had significantly impacted on the cropland soil fauna (F = 2.24, P<0.007). The number of the cropland soil fauna was related to the soil physicochemical properties caused by long-term fertilization. The result by principal component analysis, focusing on the number of 15 key soil fauna species group's diversity, evenness of community and the total soil fauna individuals indicated that the effects of SNPK, NPK, MNPK and 1.5MNPK were significantly different from that of the cropland soil fauna, in which, SNPK and NPK had the positive effect on cropland soil fauna, and MNPK and 1.5 MNPK had the negative affect, others could not be explained. By principal component I,the synthetic effect of different fertilization on the total soil fauna individuals and the group was most significant, and the effect was little on evenness and diversity. By value of eigenvectors, the maximum one was 9.6248, and the minimum one was -1.0904, that means the 6 types of fertilization did not affect evenly the cropland soil fauna.

  18. Modeling some long-term implications of CO2 fertilization for global forests and forest industries

    Science.gov (United States)

    Joseph Buongiorno

    2015-01-01

    Background: This paper explored the long-term, ceteris-paribus effects of potential CO2 fertilization on the globalforest sector. Based on the findings of Norby et al. (PNAS 2005, 102(50)) about forest response to elevated [CO2].Methods:...

  19. Effects of Long-term Located Fertilization on the Physico-chemical Property of Soil Humus

    Institute of Scientific and Technical Information of China (English)

    SHI Ji-ping; ZHANG Fu-dao; LIN Bao

    2002-01-01

    A systematic study concerning the effects of a long-term stationary fertilization on content and property of soil humus in fluvo-aquic soil sampled from Malan Farm, Xinji City, Hebei, and arid red soil and paddy red soil sampled from the Institute of Red Soil, Jinxian County, Jiangxi was conducted. The results showed that long-term fertilization had effects not only on the content and composition of soil humus, but also on the physico-chemical property of humus. With applying organic manure or combined application of organic manure and chemical fertilizer, E4 and E6 values of humic acid decreased in fluvo-aquic soil and arid red soil,but increased in paddy red soil. In paddy red soil, E4 and E6 values of humic acid increased also with a single application of chemical fertilizer, but E4 and E6 values had less change of humic acid in fluvo-aquic soil and arid red soil. The effects on the visible spectroscopic property of fulvic acid were different from that of humic acid. Long-term application of organic manure or combined application of organic manure and chemical fertilizer could increase E4 and E6 values of fulvic acid in three types of soil. Single application of chemical fertilizer had less effect on the E4 and E6. Long-term fertilization could also influence the ultraviolet spectroscopic property of humus. With a single application of organic manure or combined application of organic manure and chemical fertilizer, the ultraviolet absorbance of humic acid and fulvic acid increased in the three types of soil.But this effect was obvious only in short wave length, and the effect could decrease if the wave length increased. With a single application of chemical fertilizer the ultraviolet absorbance of fulvic acid could increase, but it of humic acid increased only in fluvo-aquic soil. Long-term application of organic manure or combined application of organic manure and chemical fertilizer could increase the content of total acidic groups, carboxy groups and

  20. Effect of Long-Term Fertilization on Soil Productivity and Nitrate Accumulation in Gansu Oasis

    Institute of Scientific and Technical Information of China (English)

    YANG Sheng-mao; LI Feng-min; SUO Dong-rang; GUO Tian-wen; WANG Jian-guo; SONG Bing-ling; JIN Shao-ling

    2006-01-01

    A long-term (1982-2001) field experiment was conducted in a calcareous soil under wheat (Triticum aestivum L.)-wheat (Triticum aestivum L.)-maize (Zea mays L.) rotation system at Zhangye, Gansu Province, China to determine the effects of long-term fertilization on crop yield, nutrients interactions, content and accumulation of nitrate-N in soil profiles. Twentyfour plots in a split-plot factorial with a combination of eight treatments (from nitrogen (N), phosphorus (P), potassium (K) and farmyard manure (M) applications) and 3 replications were selected. Main treatments were M and without M, and the sub-treatments were no-fertilizer (CK), N, NP and NPK. When P and K fertilizers were part of treatments, their ratio to N was 1N:0.22P:0.42K. All M, P and K fertilizers were applied as the basal dressing. The grain yield was harvested each experimental period and straw yield for the period from 1988 to 1997. After crop harvest in 2000, the soil was sampled from the 0-20, 20-60, 60-100, 100-140 and 140-180 cm depths to determine NO3--N content. Maize yie ld of CK in 2000 was only 28.2% of that in 1984, and wheat in 2001 was 25.7% of that observed in 1982. Average impact of fertilizers on grain yield decreased in the order of N > M > P > K. Yield response to N and P fertilizers increased with progress of the experiment. The impact of K fertilizer showed no increase in grain yield during the initial 6 years (1982-1987), moderate increase in the next 5 years (1988-1992), and considerable increase in the last 9 years (1993-2001). The straw yield trend was similar to grain yield. Accumulation and distribution of NO3--N in soil was significantly affected by annual fertilizations. Mineral fertilizers (NP and NPK) led to NO3--N accumulation in most subsoil layers, with major impact in the 20-140 cm depth. The combination of mineral fertilizers and farmyard manure (MNP and MNPK) reduced soil NO3--N accumulation in comparison to mineral fertilizers. It can be argued that

  1. The Changes in Guilin Paddy Soil Organic Matter and Rice Yield under Long-Term Fertilization

    Institute of Scientific and Technical Information of China (English)

    Qiuliang YU; Zheng TANG; Zhongfang LI; Chunlan CHEN; Xiaoxian TANG; Yanli LIN

    2016-01-01

    Rational fertilization is an important measure to increase crop yield and soil fertility. Through analysis,this paper aims to master the change characteristics of soil organic matter and rice yield under different fertilizer treatments,in order to provide an important reference for the sustainable use of soil and effective fertilization. Long-term( 19 years) rice crop rotation experiments in waterloggogenic paddy soil were conducted to investigate the change trend of crop grain yield and soil organic matter with time,reveal the dynamic characteristics and relationship between main fertility factors and crop yields using comparative analysis at three sites with conventional fertilization and non-fertilization in Guilin. The results showed that compared with previous years,the rice yield increased by 53% under the fertilization treatment and degreased by 66% under the control. Over the years,the average soil organic matter( SOM) content under fertilization treatment was 23% higher than under CK treatment. This indicates that chemical fertilizer and organic manure application can increase the rice yield and soil organic matter,and high rice yield can be attributed to the SOM increase.

  2. Physiological responses to fertilization recorded in tree rings: isotopic lessons from a long-term fertilization trial - 2008

    Science.gov (United States)

    Nitrogen fertilizer applications are common land-use management tools, but details on physiological responses to these applications are often lacking, particularly for long-term responses over decades of forest management. We used tree-ring growth patterns and stable isotopes to...

  3. Physiological responses to fertilization recorded in tree rings: Isotopic lessons from a long-term fertilization trial

    Science.gov (United States)

    Nitrogen fertilizer applications are common land use management tools, but details on physiological responses to these applications are often lacking, particularly for long-term responses over decades of forest management. We used tree ring growth patterns and stable isotopes to ...

  4. [Variation characteristics of soil carbon sequestration under long-term different fertilization in red paddy soil].

    Science.gov (United States)

    Huang, Jing; Zhang, Yang-zhu; Gao, Ju-sheng; Zhang, Wen-ju; Liu, Shu-jun

    2015-11-01

    The objective of this study was to clarify the changes of soil organic carbon (SOC) content, the saturation capacity of soil carbon sequestration and its cooperation with carbon input (crop source and organic fertilizer source carbon) under long-term (1982-2012) different fertilization in red paddy soil. The results showed that fertilization could increase SOC content. The SOC content of all the fertilization treatments demonstrated a trend of stabilization after applying fertilizer for 30 years. The SOC content in the treatments applying organic manure with mineral fertilizers was between 21.02 and 21.24 g · kg(-1), and the increase rate ranged from 0.41 to 0.59 g · kg(-1) · a(-1). The SOC content in the treatments applying mineral fertilizers only was 15.48 g · kg(-1). The average soil carbon sequestration in the treatments that applied organic manure with mineral fertilizers ranged from 43.61 to 48.43 t C · hm(-2), and the average SOC storage over the years in these treatments was significantly greater than those applying mineral fertilizers only. There was an exponentially positive correlation between C sequestration efficiency and annual average organic C input. It must input exogenous organic carbon at least at 0. 12 t C · hm(-2) · a(-1) to maintain the balance of soil organic carbon under the experimental conditions.

  5. The Effects of Long Term Nitrogen Fertilization on Soil Respiration in Rocky Mountain National Park

    Science.gov (United States)

    Allen, J.; Denning, S.; Baron, J.

    2015-12-01

    Anthropogenic activities contribute to increased levels of nitrogen deposition and elevated CO2 concentrations in terrestrial ecosystems. The role that soils play in biogeochemical cycles is an important area of uncertainty in ecosystem ecology. One of the main reasons for this uncertainty is that we have limited understanding of belowground microbial activity and how this activity is linked to soil processes. In particular, elevated CO2 may influence soil nitrogen processes that regulate nitrogen availability to plants. Warming and nitrogen fertilization may both contribute to loss of stored carbon from mountain ecosystems, because they contribute to microbial decomposition of organic matter. To study the effects of long-term nitrogen fertilization on soil respiration, we analyzed results from a 25-year field experiment in Rocky Mountain National Park. Field treatments are in old growth Engelmann spruce forests. Soil respiration responses to the effects of nitrogen fertilization on soil carbon cycling, via respiration, were investigated during the 2013 growing season. Soil moisture, temperature, and respiration rates were measured in six 30 x 30 m plots, of the six plots three are fertilized with 25 kg N ha-1 yr-1 as ammonium nitrate (NH4NO3) pellets and three receives ambient atmospheric nitrogen deposition (1-6 kg N/ha/yr) in Rocky Mountain National Park. We found that respirations rates in the fertilized plots were not significantly higher than respiration rates in the unfertilized plots. We speculate that acclimation to long-term fertilization and relatively high levels of nitrogen deposition in the control plots both contribute to the insensitivity of soil respiration to fertilization at this site.

  6. Modeling some long-term implications of CO2 fertilization for global forests and forest industries

    Institute of Scientific and Technical Information of China (English)

    Joseph; Buongiorno

    2016-01-01

    Background:This paper explored the long-term, ceteris-paribus effects of potential CO2 fertilization on the global forest sector. Based on the findings of Norby et al. (PNAS 2005, 102(50)) about forest response to elevated [CO2]. Methods:Forest productivity was increased in the Global Forest Products Model (GFPM) in proportion to the rising [CO2] projected in the IPCC scenario A1B, A2, and B2. Projections of the forest area and forest stock and of the production, consumption, prices, and trade of products ranging from fuelwood to paper and paperboard were obtained with the GFPM for each scenario, with and without CO2 fertilization beginning in 2011 and up to 2065. Results:CO2 fertilization increased wood supply, leading to lower wood prices which in turn induced modest lower prices of end products and higher global consumption. However, production and value added in industries decreased in some regions due to the relative competitive advantages and to the varying regional effects of CO2 fertilization. Conclusion:The main effect of CO2 fertilization was to raise the level of the world forest stock in 2065 by 9 to 10%for scenarios A2 and B2 and by 20%for scenario A1B. The rise in forest stock induced by fertilization was in part counteracted by its stimulation of the wood supply which resulted in lower wood prices and increased harvests.

  7. [Degradation dynamics of POPs atrazine in soils under long-term located fertilization conditions].

    Science.gov (United States)

    Wang, Jun; Zhu, Lu-sheng; Xie, Hui; Song, Yan; Sun, Rui-lian; Zhang, Fu-dao

    2007-12-01

    To evaluate the difference of POPs atrazine degradation dynamics in soils under different fertilization conditions, we set up an analysis method of the atrazine residue in soils and studied residue dynamics of atrazine in soils under a long-term located fertilization conditions. After extracted by surging with acetone, liquid-liquid partition and eluted through florisil, the residue of atrazine in soils was detected by gas chromatogram with 63Ni-ECD. The minimum detectable quantity of atrazine is 6.4 x 10(-12) g and the minimum detectable concentration is 6.4 x 10(-9) g x kg(-1) in the soil. The spiked recoveries of atrazine with the three concentration of 0.11, 1.1, 11.0 mg x kg(-1) in soils are 91.41% +/- 4.36%, 93.58% +/- 4.54%, 90.35% +/- 3.59%, according with the request of pesticide residue analysis. The degradation of atrazine in soil under a long-term located fertilization conditions was studied. The results show the degradation of atrazine follows stair dynamic equation, and the degradation half-life of atrazine in soils fertilized with CK, NPK, NPK + M, NPK + S are 20.6, 23.0, 28.5, 33.2 d, respectively. Subjected to analysis of LSR, NPK and organic fertilizers are obviously propitious to the degradation of atrazine. The separate regression and stepwise regression analysis prove the degradation half-life of atrazine in soils is well related with the content of alkaline nitrogen, organic matter and total nitrogen, and the coefficients are 0.9983, 0.9826 and 0.9521, respectively. Maybe the reason is that these soil nutrient substance offers enough the element carbon and nitrogen for action of microbe, and the higher action of microbe quickens the degradation of atrazine in soils.

  8. Long-term manure incorporation with chemical fertilizers reduced environmental nitrogen loss in rain-fed cropping systems

    Science.gov (United States)

    Improving soil fertility/productivity and reducing environmental impact of nitrogen (N) fertilization in intensive farming systems are essential for sustainable agriculture and food security around the world. The objective of this study was to determine the long-term effects of various fertilization...

  9. Fertility treatment: long-term growth and mental development of the children.

    Science.gov (United States)

    Bay, Bjørn

    2014-10-01

    Fertility treatment has been associated with obstetrical and perinatal complications. It is, however, uncertain whether fertility treatment or parental subfertility is associated with long-term development of the children. We aimed to assess the growth and mental health of children and adolescents conceived after fertility treatment compared to spontaneously conceived controls. First, we evaluated all previous studies comparing neurodevelopmental outcomes between children conceived after fertility treatment and spontaneous conceived controls. The systematic review clarified methodological limitations in the existing literature on the long-term development of children conceived after medical assisted reproduction. Although several studies had been published, large, well-controlled studies with long-term follow-up and thorough statistical adjustments were still few. Second, we evaluated the children's mental health by assessing the risk of mental disorders. We studied a population of 555,828 children conceived after spontaneous conception and 33,139 children conceived after fertility treatment with follow-up in 2012 when the children were 8-17 years old. The absolute risk and hazard ratio of overall and specific mental disorders were estimated while adjusting for potential confounding variables. Further, we estimated the association between subtypes of procedures, hormonal treatment, gamete types and cause of infertility on the one hand and the risk of mental disorders on the other. Children conceived after ovulation induction had a low, but significantly increased risks of autism spectrum disorders, hyperkinetic disorders, conduct, emotional, or social disorders, and tic disorders. Children conceived after IVF or ICSI showed no increased risk, except for a small risk of tic disorders. There was no risk systematically related to any specific type of hormone drug treatment. Thus, the increased risks may rely on residual confounding such as unknown parental factors

  10. Is subfertility or fertility treatment associated with long-term growth in the offspring?

    DEFF Research Database (Denmark)

    Bay, Bjørn; Mortensen, Erik Lykke; Kesmodel, Ulrik Schiøler

    2014-01-01

    OBJECTIVE: To study whether fertility treatment or subfertility is associated with long-term growth in the offspring. DESIGN: A prospective follow-up study including 1,773 singletons participating in the Lifestyle During Pregnancy Study at the age of 5. SETTING: Research centers. PATIENT......(S): A total of 3,478 mother-child pairs were sampled from the Danish National Birth Cohort, and 1,773 completed the outcome measurements. A total of 69 children were born after fertility treatment, whereas 132 were born to subfertile parents conceiving spontaneously but after a time to pregnancy of more than......, perinatal outcomes, and postnatal parental lifestyle characteristics were obtained from the Danish National Birth Cohort, the 5-year follow-up, and Danish health registers. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Adjusted mean differences in body weight, height, body mass index (BMI), and head...

  11. Increased ectomycorrhizal fungal abundance after long-term fertilization and warming of two arctic tundra ecosystems

    DEFF Research Database (Denmark)

    Clemmensen, Karina Engelbrecht; Michelsen, Anders; Jonasson, Sven Evert;

    2006-01-01

    the response in EM fungal abundance to long-term warming and fertilization in two arctic ecosystems with contrasting responses of the EM shrub Betula nana. •  Ergosterol was used as a biomarker for living fungal biomass in roots and organic soil and ingrowth bags were used to estimate EM mycelial production....... We measured 15N and 13C natural abundance to identify the EM-saprotrophic divide in fungal sporocarps and to validate the EM origin of mycelia in the ingrowth bags. •  Fungal biomass in soil and EM mycelial production increased with fertilization at both tundra sites, and with warming at one site....... This was caused partly by increased dominance of EM plants and partly by stimulation of EM mycelial growth. •  We conclude that cycling of carbon and nitrogen through EM fungi will increase when strongly nutrient-limited arctic ecosystems are exposed to a warmer and more nutrient-rich environment. This has...

  12. Soil pH Dynamics and Nitrogen Transformations Under Long-Term Chemical Fertilization in Four Typical Chinese Croplands

    Institute of Scientific and Technical Information of China (English)

    MENG Hong-qi; XU Ming-gang; L Jia-long; HE Xin-hua; LI Jian-wei; SHI Xiao-jun; PENG Chang; WANG Bo-ren; ZHANG Hui-min

    2013-01-01

    Long-term fertilization experiment provides the platform for understanding the proton budgets in nitrogen transformations of agricultural ecosystems. We analyzed the historical (1990-2005) observations on four agricultural long-term experiments in China (Changping, Chongqing, Gongzhuling and Qiyang) under four different fertilizations, i.e., no-fertilizer (control), sole chemical nitrogen fertilizer (FN), sole chemical phosphorous and potassium fertilizers (FPK) and chemical nitrogen, phosphorous and potassium fertilizers (FNPK). The significant decline in topsoil pH was caused not only by chemical N fertilization (0.29 and 0.89∆pH at Gongzhuling and Qiyang, respectively) but also by chemical PK fertilization (0.59∆pH at Gongzhuling). The enhancement of available nutrients in the topsoil due to long-term direct nutrients supply with chemical fertilizers was in the descending order of available P (168-599%)>available K (16-189%)>available N (9-33%). The relative rate of soil pH decline was lower under long-term judicious chemical fertilization (-0.036-0.034 ∆pH yr-1) than that under long-term sole N or PK fertilization (0.016-0.086 ∆pH yr-1). Long-term judicious chemical fertilization with N, P and K elements decreases the nutritional limitation to normal crop growth, under which more N output was distributed in biomass removal rather than the loss via nitrate leaching. We concluded that the N distribution percentage of nitrate leaching to biomass removal might be a suitable indicator to the sensitivity of agricultural ecosystems to acid inputs.

  13. Impact of Long-Term Fertilization on Phosphorus Status in Black Soil

    Institute of Scientific and Technical Information of China (English)

    HAN Xiao-Zeng; SONG Chun-Yu; WANG Shou-Yu; C. TANG

    2005-01-01

    A twelve-year field trial was carried out to determine the impact of long-term fertilization on phosphorus (P) distribution in the soil profile, P balance, and the transformation and availability of soil P in a black soil (Phaeozem, FAO). Under a wheat-soybean-corn rotation, during twelve years where no fertilizer was applied, crops removed 60 and 81 mg P kg-1 soil in the control and NK treatment, respectively. About one third of the P absorbed by crops was originated from organic P. Ca2-P, Ca8-P, Al-P and Fe-P were the main forms of inorganic P absorbed by crops. The surplus P from fertilization remained in the 0-20 cm soil layer and increased with the application rate of P. The combined application of NP or NPK increased available P to a lesser extent than the combined application of PK. Fertilizer P had mainly transformed to the Al-P, Fe-P, Ca2-P, and Ca8-P forms. By using the P budget (X), changes in total P (Y1) and available P (Y2) in soils under the current cropping system could be predicted by the equations: Y1 = 0.02 + 1.01X and Y2 = 2.08 + 0.15X.

  14. [Effect of long-term fertilization on microbial community functional diversity in black soil].

    Science.gov (United States)

    Liu, Jing-xin; Chi, Feng-qin; Xu, Xiu-hong; Kuang, En-jun; Zhang, Jiu-ming; Su, Qing-rui; Zhou, Bao-ku

    2015-10-01

    In order to study the effects of long-term different fertilization on microbial community functional diversity in arable black. soil, we examined microbial metabolic activities in two soil la- yers (0-20 cm, 20-40 cm) under four treatments (CK, NPK, M, MNPK) from a 35-year continuous fertilization field at the Ministry of Agriculture Key Field Observation Station of Harbin Black Soil Ecology Environment using Biolog-ECO method. The results showed that: in the 0-20 cm soil layer, combined application of organic and inorganic fertilizer(MNPK) increased the rate of soil microbial carbon source utilization and community metabolism richness, diversity and dominance; In the 20-40 cm layer, these indices of the MNPK treatment was lower than that of the NPK treat- ment; while NPK treatment decreased soil microbial community metabolism evenness in both layers. Six groups of carbon sources used by soil microbes of all the treatments were different between the two soil layers, and the difference was significant among all treatments in each soil layer (P functional diversity in both tillage soil layer and down soil layers, and chemical fertilization alone had a larger influence on the microbial community functional diversity in the 20-40 cm layer.

  15. Long-term fertilization alters the relative importance of nitrate reduction pathways in salt marsh sediments

    Science.gov (United States)

    Peng, Xuefeng; Ji, Qixing; Angell, John H.; Kearns, Patrick J.; Yang, Hannah J.; Bowen, Jennifer L.; Ward, Bess B.

    2016-08-01

    Salt marshes provide numerous valuable ecological services. In particular, nitrogen (N) removal in salt marsh sediments alleviates N loading to the coastal ocean. N removal reduces the threat of eutrophication caused by increased N inputs from anthropogenic sources. It is unclear, however, whether chronic nutrient overenrichment alters the capacity of salt marshes to remove anthropogenic N. To assess the effect of nutrient enrichment on N cycling in salt marsh sediments, we examined important N cycle pathways in experimental fertilization plots in a New England salt marsh. We determined rates of nitrification, denitrification, and dissimilatory nitrate reduction to ammonium (DNRA) using sediment slurry incubations with 15N labeled ammonium or nitrate tracers under oxic headspace (20% oxygen/80% helium). Nitrification and denitrification rates were more than tenfold higher in fertilized plots compared to control plots. By contrast, DNRA, which retains N in the system, was high in control plots but not detected in fertilized plots. The relative contribution of DNRA to total nitrate reduction largely depends on the carbon/nitrate ratio in the sediment. These results suggest that long-term fertilization shifts N cycling in salt marsh sediments from predominantly retention to removal.

  16. Soil Organic Carbon, Black Carbon, and Enzyme Activity Under Long-Term Fertilization

    Institute of Scientific and Technical Information of China (English)

    SHAO Xing-hua; ZHENG Jian-wei

    2014-01-01

    The present study aims to understand the effects of long-term fertilization on soil organic carbon (SOC), black carbon (BC), enzyme activity, and the relationships among these parameters. Paddy ifeld was continuously fertilized over 30 yr with nine different fertilizer treatments including N, P, K, NP, NK, NPK, 2NPK (two-fold NPK), NPK+manure (NPKM), and CK (no fertilization), N, 90 kg urea-N ha-1 yr-1; P, 45 kg triple superphosphate-P2O5 ha-1 yr-1; K, 75 kg potassium chloride-K2O ha-1 yr-1;and pig manure, 22 500 kg ha-1 yr-1. Soil samples were collected and determined for SOC, BC content, and enzyme activity. The results showed that the SOC in the NPKM treatment was signiifcantly higher than those in the K, P, and CK treatments. The lowest SOC content was found in the CK treatment. SOC content was similar in the N, NP, NK, NPK, 2NPK, and NPKM treatments. There was no signiifcant difference in BC content among different treatments. The BC-to-SOC ratios (BC/SOC) ranged from 0.50 to 0.63, suggesting that BC might originate from the same source. Regarding enzyme activity, NPK treatment had higher urease activity than NPKM treatment. The urease activity of NPKM treatment was signiifcantly higher than that of 2NPK, NP, N, P, K, CK, and NPKM treatment which produced higher activities of acid phosphatase, catalase, and invertase than all other treatments. Our results indicated that long-term fertilization did not signiifcantly affect BC content. Concurrent application of manure and mineral fertilizers increased SOC content and signiifcantly enhanced soil enzyme activities. Correlation analysis showed that catalase activity was signiifcantly associated with invertase activity, but SOC, BC, and enzyme activity levels were not signiifcantly correlated with one another. No signiifcant correlations were observed between BC and soil enzymes. It is unknown whether soil enzymes play a role in the decomposition of BC.

  17. [Effects of long-term different fertilizations on biomass and nutrient content of maize root].

    Science.gov (United States)

    Cai, Miao; Meng, Yan; Mohammad Amin, Ahmadzai; Zhou, Jian-bin

    2015-08-01

    Taking two long-term local field trials at the south edge of the Loess Plateau, which were found in 1990 and 2003, respectively, as test subjects, the effects of different fertilization practices on the maize root biomass and nutrient content were investigated in this paper. Maize roots in the 0-20 cm top soil post-maize harvest from the different fertilization practices were collected by hand in October 2011. The results showed that compared with control without fertilization and N, NK, or PK treatments, the NP, NPK, fertilizers plus manure (M1NPK and M2NPK) or plus straw return (SNPK) treatments significantly increased the dry mass of maize root. The C, N, P and K contents in maize roots in the NP, NPK, M1 NPK, M2NPK and SNPK treatments were also significantly higher than those of control, especially in the NPK plus organic manure treatments (M1 NPK and M2NPK) in the trial. Compared with the N fertilizer free treatment (N0), root biomass in the 120 kg N · hm(-2) (N120) and 240 kg N · hm(-2) ( N240) fertilization treatments increased by 38% and 45%, respectively, but there was no significant difference between N120 and N240 treatments. Nitrogen fertilizer application (N120 and N240) also improved the C, N, P and K contents in maize root. The water soluble organic C and total soluble N contents of maize root in the NP, NPK, M1NPK, M2NPK, SNPK and the N120 and N240 treatments were greater than those of control and other treatments. Otherwise, the cellulose and lignin contents in maize roots declined in the NPK, M1NPK, M2NPK, and SNPK treatments compared with other treatments. So the root C/N and lignin/N ratios in the control, PK and N0 treatments were significantly higher than those in the NP, NPK, M1NPK, M2NPK and SNPK treatments. We concluded that the optimum fertilization (e. g., NP, NPK, MNPK and SNPK treatments) could increase maize root growth and nutrient content and improve soil fertility and carbon sequestration through root residue into soil.

  18. Soil ionomic and enzymatic responses and correlations to fertilizations amended with and without organic fertilizer in long-term experiments

    Science.gov (United States)

    Feng, Xumeng; Ling, Ning; Chen, Huan; Zhu, Chen; Duan, Yinghua; Peng, Chang; Yu, Guanghui; Ran, Wei; Shen, Qirong; Guo, Shiwei

    2016-04-01

    To investigate potential interactions between the soil ionome and enzyme activities affected by fertilization with or without organic fertilizer, soil samples were collected from four long-term experiments over China. Irrespective of variable interactions, fertilization type was the major factor impacting soil ionomic behavior and accounted for 15.14% of the overall impact. Sampling site was the major factor affecting soil enzymatic profile and accounted for 34.25% of the overall impact. The availabilities of Pb, La, Ni, Co, Fe and Al were significantly higher in soil with only chemical fertilizer than the soil with organic amendment. Most of the soil enzyme activities, including α-glucosidase activity, were significantly activated by organic amendment. Network analysis between the soil ionome and the soil enzyme activities was more complex in the organic-amended soils than in the chemical fertilized soils, whereas the network analysis among the soil ions was less complex with organic amendment. Moreover, α-glucosidase was revealed to generally harbor more corrections with the soil ionic availabilities in network. We concluded that some of the soil enzymes activated by organic input can make the soil more vigorous and stable and that the α-glucosidase revealed by this analysis might help stabilize the soil ion availability.

  19. Influences of Long-Term Fertilizer and Tillage Management on Soil Fertility of the North China Plain

    Institute of Scientific and Technical Information of China (English)

    NIU Ling-An; HAO Jin-Min; ZHANG Bao-Zhong; NIU Xin-Sheng

    2011-01-01

    In the North China Plain,fertilizer management and tillage practices have been changing rapidly during the last three decades; however,the influences of long-term fertilizer applications and tillage systems on fertility of salt-affected soils have not been well understood under a winter wheat (Triticum aestivum L.)-maize (Zea mays L.) annual double cropping system.A field experiment was established in 1985 on a Cambosol at the Quzhou Experimental Station,China Agricultural University,to investigate the responses of soil fertility to fertilizer and tillage practices.The experiment was established as an orthogonal design with nine treatments of different tillage methods and/or fertilizer applications.In October 2001,composite soil samples were collected from the 0-20 and 20-40 cm layers and analyzed for soil fertility indices.The results showed that after 17 years of nitrogen (N) and phosphorous (P) fertilizer and straw applications,soil organic matter (SOM) in the top layer was increased significantly from 7.00 to 9.30-13.14 g kg-1 in the 0-20 cm layer and from 4.00 to 5.48-7.75 g kg-1 in the 20-40 cm layer.Soil total N (TN) was increased significantly from 0.37 and 0.22 to 0.79-1.11 and 0.61-0.73 g N kg-1 in the 0-20 and 20-40 cm layers,respectively,with N fertilizer application; however,there was no apparent effect of straw application on TN content.The amounts of soil total P (TP) and rapidly available P (RP) were increased significantly from 0.60 to 0.67-1.31 g kg-1 in the 0-20 cm layer and from 0.52 to 0.60-0.73 g kg-1 in the 20-40 cm layer with P fertilizer application,but were decreased with combined N and P fertilizer applications.The applications of N and P fertilizers significantly increased the crop yields,but decreased the rapidly available potassium (RK) in the soil.Straw return could only meet part of the crop potassium requirements.Our results also suggested that though some soil fertility parameters were maintained or enhanced under the long-term

  20. Nitrogen uptake during one year in subarctic plant functional groups and in microbes after long-term warming and fertilization

    DEFF Research Database (Denmark)

    Sørensen, Pernille Lærkedal; Michelsen, Anders; Jonasson, Sven Evert

    2008-01-01

    For the first time in an arctic long-term warming and fertilization experiment, the short-term (days) and longer-term (month and year) nitrogen (N) uptake and allocation in plants, microbes, and soil pools were studied, with 15N-labeling of an organic nitrogen form, glycine. The long-term warming...... and fertilization had no marked effect on soil inorganic N content, but both dissolved organic N (DON) and plant biomass did increase after fertilization. Soil microbes initially immobilized most of the added 15N, but in the following months, they lost two-thirds, while label concentration in plants increased....... After a year, however, the 15N recovered in microbes was still 10-fold higher than that in the plant biomass, showing the high importance of soil microbes in nutrient retention in arctic ecosystems, irrespective of the impact of long-term warming or fertilization. The effects of the treatments...

  1. Soil organic carbon dynamics under long-term fertilizations in arable land of northern China

    Science.gov (United States)

    Zhang, W. J.; Wang, X. J.; Xu, M. G.; Huang, S. M.; Liu, H.; Peng, C.

    2010-02-01

    Soil carbon sequestration is a complex process influenced by agricultural practices, climate and soil conditions. This paper reports a study of long-term fertilization impacts on soil organic carbon (SOC) dynamic from six long-term experiments. The experiment sites are located from warm-temperate zone with a double-cropping system of corn (Zea mays L.) - wheat (Triticum Aestivium L.) rotation, to mild-temperate zones with mono-cropping systems of continuous corn, or a three-year rotation of corn-wheat-wheat. Mineral fertilizer applications result in an increasing trend in SOC except in the arid and semi-arid areas with the mono-cropping systems. Additional manure application is important to maintain SOC level in the arid and semi-arid areas. Carbon conversion rate is significant lower in the warm-temperate zone with double cropping system (6.8%-7.7%) than that in the mild-temperate areas with mono-cropping systems (15.8%-31.0%). The conversion rate is significantly correlated with annual precipitation and active accumulative temperature, i.e., higher conversion rate under lower precipitation and/or temperature conditions. Moreover, soil high in clay content has higher conversion rate than soils low in clay content. Soil carbon sequestration rate ranges from 0.07 to 1.461 t ha-1 year-1 in the upland of northern China. There is significantly linear correlation between soil carbon sequestration and carbon input at most sites, indicating that these soils are not carbon-saturated thus have potential to migrate more CO2 from atmosphere.

  2. Long-term outcomes of fertility-sparing treatment of atypical polypoid adenomyoma with medroxyprogesterone acetate.

    Science.gov (United States)

    Nomura, Hidetaka; Sugiyama, Yuko; Tanigawa, Terumi; Matoda, Maki; Kanao, Hiroyuki; Kondo, Eiji; Takeshima, Nobuhiro

    2016-01-01

    Our objective was to analyze the long-term oncologic outcomes of fertility-preserving hormonal treatment with medroxyprogesterone acetate (MPA) in patients with APA. In a retrospective chart review, we identified patients with APA who were treated with MPA for fertility preservation at our hospital between 2001 and 2011. Eighteen patients with histologically diagnosed APA were identified. Clinical data including treatment, obstetrical, and oncologic outcomes were recorded. The mean observation period was 77.6 months (median 73.5, range 22-142), and the mean age was 33.6 years. Four patients also developed well-differentiated endometrial carcinoma. After the treatment, 14 patients (77.8 %) achieved either a complete response or partial response. Eight patients experienced recurrence, while four experienced persistent disease. Ten patients (55.6 %) eventually underwent hysterectomy. The median time to hysterectomy was 40.3 months (range 24-68). Nine patients progressed to endometrial cancer, and one experienced persistent APA. Among younger patients (<35 years of age), four out of five patients who were married could have children. Seven patients (38.9 %) showed no evidence of the disease during the observation period (median 60 months, range 22-117 months). No one died because of the disease during the observation period. MPA yields a high response rate in APA, and if only younger patients are considered, a favorable pregnancy rate can be obtained. However, because recurrence rate is high, long-term follow-up under supervision of a trained gynecologic oncologist is required. To confirm MPA's utility, multi-center collaboration would be warranted.

  3. Effects of long-term phosphorus fertilization and straw incorporation on phosphorus fractions in subtropical paddy soil

    Institute of Scientific and Technical Information of China (English)

    LI Yu-yuan; YANG Rui; GAO Ru; WEI Hong-an; CHEN An-lei; LI Yong

    2015-01-01

    Study on soil phosphorus (P) fraction is an important aspect in probing the mechanisms of soil P accumulation in farm-land and mitigating its losing risk to the environment. We used a sequential extraction method to evaluate the impacts of long-term fertilization and straw incorporation on inorganic, organic, and residual P (Pi, Po, and Pre) fractions in the plow layer (0–20 cm) of acidic paddy soil in southern China. The experiment comprised of six treatments:(i) no fertilizer control (CK); (i ) straw incorporation and green manure (SG); (i i) nitrogen and P fertilizer (NP); (iv) NP+SG; (v) NP+K fertilizer (NPK);and (vi) NPK+SG. The results showed that, compared to the initial total soil P content (TSP, 600 mg kg–1 in 1990), long-term (20 years) combined continuous P fertilizer and SG signiifcantly increased P accumulation (by 13–20%) while single fertilization (39.3 kg P ha–1 yr–1) could maintain soil P status at the most. The average soil P fractions comprised of extractable Pi, Po, and Pre by 51.7, 33.4, and 14.9%in total soil P, respectively. With comparison of no fertilizer addition (CK), long-term single fertilization signiifcantly (P0.05), our data indicate that SG may partial y substitute for fertilizer P input and minimizing soil P accumulation and subsequent environmental risk in the subtropical paddy soil.

  4. Long-term fertilization modifies the structures of soil fulvic acids and their binding capability with Al.

    Science.gov (United States)

    Wu, Jun; Wu, Minjie; Li, Chunping; Yu, Guanghui

    2014-01-01

    The binding characteristics of organic ligands and minerals in fulvic acids (FAs) with Al are essential for understanding soil C sequestration, remain poorly understood. In this study, Fourier transform infrared (FTIR) spectroscopy combined with two-dimensional correlation spectroscopy (2DCOS) analysis was applied for the first time to explore the binding of Al with organic ligands and minerals in soil FAs. For these analyses, two contrasting treatments were selected from a long-term (i.e., 22-year) fertilization experiment: chemical (NPK) fertilization and swine manure (SM) fertilization. The results showed that the long-term application of organic and inorganic fertilizers to soils had little effect on the compositions of the fluorescent substances and organic ligands in the soil FAs. However, long-term SM fertilization increased the weathered Al and Si concentrations in the soil FAs compared with long-term chemical fertilization. Furthermore, organic ligands in the soil FAs were mainly bound with Al in the NPK treatment, whereas both organic ligands and minerals (Al-O-Si, Si-O) were bound with Al under the M fertilization conditions. Both transmission electron microscopy (TEM) images and X-ray diffraction spectra demonstrated that amorphous and short-range-ordered nanominerals were abundant in the soil FAs from the SM plot in contrast to the soil FAs from the NPK plot. This result illustrates the role nanominerals play in the preservation of soil FAs by during long-term organic fertilization. In summary, the combination of FTIR and 2D correlation spectroscopy is a promising approach for the characterization of the binding capability between soil FAs and Al, and a better understanding FA-Al binding capability will greatly contribute to global C cycling.

  5. Effect of Long-Term Fertilization on Organic Nitrogen Forms in a Calcareous Alluvial Soil on the North China Plain

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In order to illustrate the change of nitrogen (N) supply capacity after long-term application of manure and chemical fertilizer, as well as to properly manage soil fertility through fertilizer application under the soil-climatic conditions of the North China Plain, organic N forms were quantified in the topsoil with different manure and chemical fertilizer treatments in a 15-year fertilizer experiment in a Chinese calcareous alluvial soil Soil total N (TN) and various organic N forms were significantly influenced by long-term application of chemical fertilizer and manure. TN, total hydrolysable N, acid-insoluble N, amino acid N and ammonium N in the soil increased significantly (P < 0.05) with increasing manure and fertilizer N rates, but were not influenced by increasing P rates. Also, application of manure or N fertilizer or P fertilizer did not significantly influence either the quantity of amino sugar N or its proportion of TN. Application of manure significantly increased (P < 0.05) hydrolysable unknown N, but adding N or P did not. In addition, application of manure or N fertilizer or P fertilizer did not significantly influence the proportions of different soil organic N forms.

  6. Long Term Population, City Size and Climate Trends in the Fertile Crescent: A First Approximation.

    Directory of Open Access Journals (Sweden)

    Dan Lawrence

    Full Text Available Over the last 8000 years the Fertile Crescent of the Near East has seen the emergence of urban agglomerations, small scale polities and large territorial empires, all of which had profound effects on settlement patterns. Computational approaches, including the use of remote sensing data, allow us to analyse these changes at unprecedented geographical and temporal scales. Here we employ these techniques to examine and compare long term trends in urbanisation, population and climate records. Maximum city size is used as a proxy for the intensity of urbanisation, whilst population trends are modelled from settlement densities in nine archaeological surveys conducted over the last 30 years across the region. These two measures are then compared with atmospheric moisture levels derived from multiple proxy analyses from two locations close to the study area, Soreq Cave in Israel and Lake Van in south-eastern Turkey, as well as wider literature. The earliest urban sites emerged during a period of relatively high atmospheric moisture levels and conform to a series of size thresholds. However, after the Early Bronze Age maximum urban size and population levels increase rapidly whilst atmospheric moisture declines. We argue that although the initial phase of urbanization may have been linked to climate conditions, we can see a definitive decoupling of climate and settlement patterns after 2000 BC. We relate this phenomenon to changes in socio-economic organisation and integration in large territorial empires. The complex relationships sustaining urban growth during this later period resulted in an increase in system fragility and ultimately impacted on the sustainability of cities in the long term.

  7. Long-term effects of low fertility in the region of former Yugoslavia

    Directory of Open Access Journals (Sweden)

    Nikitović Vladimir

    2016-01-01

    Full Text Available After the dissolution of the socialist Yugoslavia (SFRY in 1991, the quality and availability of demographic and migration statistics in the region as a whole, and especially in some of its parts are deteriorated. In addition, census rounds are not being held regularly throughout the region as of 1991. Thus, producing population projections has become rather challenging in comparison to the period of SFRY. This paper made an effort in order to overcome obstacles in terms of historic data and jump-off projection values for the whole region in accordance with adjusted data from national records. Until 1991, population of the region had been increasing almost linearly. Although SFRY was characterized by significant sub-regional differences in terms of the beginning and the pace of demographic transition, the current total fertility rate throughout the region is below 2.1. The aim of the paper is to consider the long-term implications of low fertility and whether in this respect there would be a demographic homogenization of the region. For that purpose, we relied on the UN WPP2015 model used by the UN Population Division for producing its 2015 World Population Prospects. It enabled several important features from the viewpoint of the main tasks of the paper: the methodologically consistent datasets on main demographic indicators, probabilistic approach for modelling and forecasting fertility and mortality, the opportunity to adjust initial datasets for known issues on data quality (Serbia, Kosovo, Bosnia & Herzeg., and ability to adjust data distribution according to the former administrative division of SFRY. The last one was of particular importance as it allowed us to take into account the well-known diversity of fertility patterns in Serbia (Vojvodina, Central Serbia and Kosovo, and to make a distinction in projection results between the sub-regions differed by the onset and tempo of fertility transition. The UN concept of post

  8. INFLUENCE OF LONG TERM APPLICATION OF FERTILIZERS ON SOIL ORGANIC MATTER CONTENT

    Directory of Open Access Journals (Sweden)

    K.V. Naga Madhuri

    2013-06-01

    Full Text Available The soil samples were collected from the soils of Long Term Fertilizer Experiments that have been fertilized for the last 25 years from a control plot (receiving no fertilizer/FYM; b plot receiving 100% NPK fertilizer application and c Plot receiving 100% N in the form of FYM, to study the changes in nature and amount of organic matter and these were compared with a similar adjacent soil under natural vegetation. The soil samples were collected from 0-15 cm (surface and 15-30 cm (sub surface layers. The humic substances were fractionated by Tyurins method. The total N and available N content was determined and C/N ratio was calculated. The humic acid was isolated, purified and analyzed for oxygen containing functional groups and spectral properties. It was observed that the soil under natural vegetation had a higher total N while the soil under continuous cultivation had higher available N. The C/N ratio of soil under natural vegetation was high compared to the soil under continuous cultivation. These values were high in surface layers compare to sub surface layers. The oxygen containing functional groups in Humic acid (HA were high in soil under natural vegetation compared to the soil under continuous cultivation. The total acidity and COOH content of surface layers was high compared to sub surface layers in soils under both situations. Phenolic OH groups of subsurface layer was high in soil under natural vegetation and continuous cultivation indicating that this group in sub surface layers and high potential for interaction with clays and metal ions. The higher contents of total acidity and –COOH groups in soil under natural vegetation could be attributed to the difference in chemical composition and molecular weight of humic substances. The E4/E6 ratios of HA’S were less than 5.0 indicating high degree of condensation of aromatic humic acid. The potentiometric titrations of humic acids with standard 0.1 N NaOH indicated a gradual increase

  9. Long-term fertilization alters chemically-separated soil organic carbon pools: Based on stable C isotope analyses

    Science.gov (United States)

    Dou, Xiaolin; He, Ping; Cheng, Xiaoli; Zhou, Wei

    2016-01-01

    Quantification of dynamics of soil organic carbon (SOC) pools under the influence of long-term fertilization is essential for predicting carbon (C) sequestration. We combined soil chemical fractionation with stable C isotope analyses to investigate the C dynamics of the various SOC pools after 25 years of fertilization. Five types of soil samples (0–20, 20–40 cm) including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, IN; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into recalcitrant and labile fractions, and the fractions were analysed for C content, C:N ratios, δ13C values, soil C and N recalcitrance indexes (RIC and RIN). Chemical fractionation showed long-term MNPK fertilization strongly increased the SOC storage in both soil layers (0–20 cm = 1492.4 gC m2 and 20–40 cm = 1770.6 gC m2) because of enhanced recalcitrant C (RC) and labile C (LC). The 25 years of inorganic fertilizer treatment did not increase the SOC storage mainly because of the offsetting effects of enhanced RC and decreased LC, whereas no clear SOC increases under the SNPK fertilization resulted from the fast decay rates of soil C.

  10. Long-term fertilization alters chemically-separated soil organic carbon pools: Based on stable C isotope analyses.

    Science.gov (United States)

    Dou, Xiaolin; He, Ping; Cheng, Xiaoli; Zhou, Wei

    2016-01-01

    Quantification of dynamics of soil organic carbon (SOC) pools under the influence of long-term fertilization is essential for predicting carbon (C) sequestration. We combined soil chemical fractionation with stable C isotope analyses to investigate the C dynamics of the various SOC pools after 25 years of fertilization. Five types of soil samples (0-20, 20-40 cm) including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, IN; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into recalcitrant and labile fractions, and the fractions were analysed for C content, C:N ratios, δ(13)C values, soil C and N recalcitrance indexes (RIC and RIN). Chemical fractionation showed long-term MNPK fertilization strongly increased the SOC storage in both soil layers (0-20 cm = 1492.4 gC m(2) and 20-40 cm = 1770.6 gC m(2)) because of enhanced recalcitrant C (RC) and labile C (LC). The 25 years of inorganic fertilizer treatment did not increase the SOC storage mainly because of the offsetting effects of enhanced RC and decreased LC, whereas no clear SOC increases under the SNPK fertilization resulted from the fast decay rates of soil C.

  11. Carbon Sequestration in Soil Humic Substances Under Long-Term Fertilization in a Wheat-Maize System from North China

    Institute of Scientific and Technical Information of China (English)

    SONG Xiang-yun; LIU Shu-tang; LIU Qing-hua; ZHANG Wen-ju; HU Chun-guang

    2014-01-01

    The changes in humic substances (HS) is fundamental in detecting soil carbon sequestration mechanisms in natural and cultivated environments. Based on a long-term trial, the amounts of water dissolved substances (WSS), humic acid (HA), fulvic acid (FA) and humin (HU) were determined to explore the impact of long-term fertilization on HS. Increases in the amounts of WSS, HA, FA and HU were signiifcant different among the treatments with manure. A signiifcant correlation was found between the increased soil organic carbon (SOC) and HS (R2=0.98, P<0.01). The change in the E4/E6 ratio was signiifcantly correlated with the increased SOC (R2=0.88, P<0.01), HA (R2=0.91, P<0.01), FA (R2=0.91, P<0.01) and HU (R2=0.88, P<0.01). The cluster was mainly divided into two parts as manure fertilization and inorganic fertilization, based on the increases in HA, FA and HU. These results suggest that long term fertilization with manure favours carbon sequestration in HS and is mainly stabilized as HU, while the HA becomes more aliphatic. We conclude that increases in SOC can be linked to changes in the molecular characteristics of HS fractions under long term fertilization.

  12. Cadmium levels in soils and plants from some long-term soil fertility experiments in the United States of America

    Energy Technology Data Exchange (ETDEWEB)

    Mortvedt, J.J.

    Phosphate fertilizers contain varying amounts of Cd and other heavy metals as contaminants from phosphate rock (PR). To determine whether periodic applications of P fertilizers resulted in measurable accumulations of Cd in soils and in harvested crops, soil and plant tissue samples from nine long-term (>50 yr) soil fertility experiments in the USA were analyzed for Cd, as well as P and other elements. Annual Cd rates were estimated to range from 0.3 to 1.2 g ha/sup -1/ in these experiments. Plant tissues analyzed were corn (Zea mays L.), soybean (Glycine max L. Merr.), and wheat (Triticum aestivum L.) leaves or grain, and timothy (Phleum pratense L.) forage. Results from these long-term experiments have shown that plant uptake of Cd contaminants in P fertilizers containing < 10 mg Cd kg/sup -1/ is negligible. While the Cd accumulations in soil in these experiments could not be calculated, they would approximate that accumulated in most agricultural soils in the USA at this time. About 70% of the P fertilizers is produced from Florida PR, which contains <10 mg kg/sup -1/ of Cd, as compared with about 10% from the western USA, which contains higher Cd levels. Therefore, adding Cd to soils as a contaminant in P fertilizers at rates ranging from 0.3 to 1.2 g Cd ha/sup -1/ does not appear to result in increased Cd levels in plants as a result of long-term P fertilization.

  13. Factors affecting potassium fixation in seven soils under 15-year long-term fertilization

    Institute of Scientific and Technical Information of China (English)

    ZHANG HuiMin; XU MingGang; ZHANG WenJu; HE XinHua

    2009-01-01

    Potassium (K) fixation by seven soils, including black soil, fluvo-aquic soil, grey desert soil, loess soil, paddy soil, red soil and purple soil, was determined by laboratory simulation under a fifteen-year-pe-riod of long-term fertilization. Factors affecting soil K fixation were then discussed by factor analysis and stepwise regression. Magnitude of soil K fixation rate was as follows: the black soil > the purple soil > the loess soil > the fluvo-aquic soil > the paddy soil > the grey desert soil > the red soil. Our re-sulta showed that soil K fixation capacity was significantly affected by the clay mineral types in the soils. Potassium fixation capacity of soils, whose 2:1 layer silicates were dominant minerals, was af-fected by two components extracted by the method of principal component analysis: the first including soil available K, slow available K and K+ saturation, and the second including cation exchange capacity (CEC), soil organic matter (SOM) and <0.002 mm clay contents. Potassium fixation rate was mainly af-fected by K+ saturation and CEC with lower added K concentration (from 0.4 to 1.6 g/L), and by K+ saturation and <0.002 mm clay content with higher added K concentration (from 2.4 to 4.0 g/L).

  14. Long-term effect of tillage, nitrogen fertilization and cover crops on soil organic carbon and total nitrogen content

    OpenAIRE

    2011-01-01

    Metadata only record No-till practices, in conjunction with cover crops and nitrogen fertilization, have been shown to augment soil organic carbon content and total nitrogen content. However, interactions between these components in a no-till system are not well-known. This study offers a long-term (1993-2008) comparative analysis of conventional versus no-till practices as well as a some insight regarding the synergies between no-till, nitrogen fertilization, and cover crops. Maize, wheat...

  15. Long term effects of ash fertilization of reed canary grass; Laangtidseffekter av askgoedsling vid roerflensodling

    Energy Technology Data Exchange (ETDEWEB)

    Palmborg, Cecilia; Lindvall, Eva

    2011-03-15

    harvest. The main component of the ash is silica and silica concentrations are higher when reed canary grass is grown on clay soil than on peat soil. In an earlier project within the department of agricultural research for northern Sweden, SLU Umea, reed canary grass growing on peat soil was fertilized with ash from cocombustion of reed canary grass and sorted municipal waste. This ash was beneficial for the growth of the grass and did not give increased heavy metal contents. However the experiment only lasted two years so no conclusions could be drawn about long-term effects. Crop yields and elemental composition of the crop: The yields varied very much from year to year. The first two production years, 2004 and 2005 the yield was at expected levels, 6000-7000 kg dry matter per ha and year. After that, 2006-2009 the yields have been lower than expected, 1500 - 4000 kg dry matter per ha and year. The reason for this is not known, but it could be related to climate or pests. There were no significant differences in yield between the treatments. Samples from each plot from the last harvest and stored samples from 2004 were analyzed for nutrient and heavy metal content. There were only minor significant differences between the treatments: The ash and the potassium and calcium concentrations 2009 in grass from treatment A, ash from co-combustion of reed canary grass and waste, was slightly higher than in the NPK fertilized control. The magnesium concentration in 2009 was slightly higher in grass fertilized with reed canary grass ash than in the control grass. Element balances and soil concentrations of elements: Because of the low yield levels the amounts of P and K applied were much higher than the removal with harvests (Table 2). This resulted in an increase in plant available P and K in the top soil between 2003 and 2008 (Table 3). However, in the subsoil there was a decrease especially in plant available P. The only significant differences in soil nutrients between the

  16. Residual Long-Term Effects of Forest Fertilization on Tree Growth and Nitrogen Turnover in Boreal Forest

    Directory of Open Access Journals (Sweden)

    Fredrik From

    2015-04-01

    Full Text Available The growth enhancing effects of forest fertilizer is considered to level off within 10 years of the application, and be restricted to one forest stand rotation. However, fertilizer induced changes in plant community composition has been shown to occur in the following stand rotation. To clarify whether effects of forest fertilization have residual long-term effects, extending into the next rotation, we compared tree growth, needle N concentrations and the availability of mobile soil N in young (10 years Pinus sylvestris L. and Picea abies (L. H. Karst. stands. The sites were fertilized with 150 kg·N·ha−1 once or twice during the previous stand rotation, or unfertilized. Two fertilization events increased tree height by 24% compared to the controls. Needle N concentrations of the trees on previously fertilized sites were 15% higher than those of the controls. Soil N mineralization rates and the amounts of mobile soil NH4-N and NO3-N were higher on sites that were fertilized twice than on control sites. Our study demonstrates that operational forest fertilization can cause residual long-term effects on stand N dynamics, with subsequent effects on tree growth that may be more long-lasting than previously believed, i.e., extending beyond one stand rotation.

  17. Effect of Long-Term Application of Chemical Fertilizers on microbial biomass and Functional Diversity of a Black Soil

    Institute of Scientific and Technical Information of China (English)

    KONG Wei-Dong; ZHU Yong-Guan; FU Bo-Jie; HAN Xiao-Zeng; ZHANG Lei; HE Ji-Zheng

    2008-01-01

    An experiment with seven N, P, K-fertilizer treatments, i.e., control (no fertilizer), NP, NK, PK, NPK, NP2K, and NPK2 where P2 and K2 indicate double amounts of P and K fertilizers respectively, was conducted to examine the effect of long-term continuous application of chemical fertilizers on microbial biomass and functional diversity of a black soil (Udoll in the USDA Soil Taxonomy) in Northeast China. The soil microbial biomass C ranged between 94 and 145 mg kg-1, with the NK treatment showing a lower biomass; the functional diversity of soil microbial community ranged from 4.13 to 4.25, with an increasing tendency from control to double-fertilizer treatments, and to triple-fertilizer treatments. The soil microbial biomass, and the microbial functional diversity and evenness did not show any significant differences among the different fertilizer treatments including control, suggesting that the long-term application of chemical fertilization would not result in significant changes in the microbial characteristics of the black soil.

  18. [Effects of long-term fertilization on soil organic nitrogen components in paddy soil derived from red earth].

    Science.gov (United States)

    Zong, Hai-ying; Wang, Kai-rong; Xie, Xiao-li

    2008-08-01

    A 16-year long-term fertilization experiment was conducted on paddy soil derived from red earth to investigate the effects of different fertilization patterns on the concentrations of soil organic nitrogen (N) components. When chemical fertilizers were applied only, the soil nitrogen content was slightly influenced. Organic fertilization, especially its combination with chemical fertilization, could significantly increase the contents of soil mineralizable N and organic nitrogen by 55.2% and 38.8%, respectively. In addition, organic fertilization could significantly improve the components of acid hydrolysable N, and lead to the increase of ammonium N (AN) , amino sugar N (ASN), and hydrolysable unidentified N (HUN) by 36.5%, 68.4%, and 73.9%, respectively. When the organic fertilization was combined with chemical fertilization, soil amino acid N content was increased by 71.1%, while HUN content was decreased by 34.5%. In all fertilization treatments, the cumulative amount of soil mineralized N increased with increasing incubation time. The content of soil mineralized N under organic fertilization and its combination with chemical fertilization was higher than that under chemical fertilization.

  19. Reducing soil phosphorus fertility brings potential long-term environmental gains: A UK analysis

    Science.gov (United States)

    Withers, Paul J. A.; Hodgkinson, Robin A.; Rollett, Alison; Dyer, Chris; Dils, Rachael; Collins, Adrian L.; Bilsborrow, Paul E.; Bailey, Geoff; Sylvester-Bradley, Roger

    2017-05-01

    Soil phosphorus (P) fertility arising from historic P inputs is a major driver of P mobilisation in agricultural runoff and increases the risk of aquatic eutrophication. To determine the environmental benefit of lowering soil P fertility, a meta-analysis of the relationship between soil test P (measured as Olsen-P) and P concentrations in agricultural drainflow and surface runoff in mostly UK soils was undertaken in relation to current eutrophication control targets (30-35 µg P L-1). At agronomic-optimum Olsen P (16-25 mg kg-1), concentrations of soluble reactive P (SRP), total dissolved P (TDP), total P (TP) and sediment-P (SS-P) in runoff were predicted by linear regression analysis to vary between 24 and 183 µg L-1, 38 and 315 µg L-1, 0.2 and 9.6 mg L-1, and 0.31 and 3.2 g kg-1, respectively. Concentrations of SRP and TDP in runoff were much more sensitive to changes in Olsen-P than were TP and SS-P concentrations, which confirms that separate strategies are required for mitigating the mobilisation of dissolved and particulate P forms. As the main driver of eutrophication, SRP concentrations in runoff were reduced on average by 60 µg L-1 (71%) by lowering soil Olsen-P from optimum (25 mg kg-1) to 10 mg kg-1. At Olsen-P concentrations below 12 mg kg-1, dissolved hydrolysable P (largely organic) became the dominant form of soluble P transported. We concluded that maintaining agronomic-optimum Olsen-P could still pose a eutrophication risk, and that a greater research focus on reducing critical soil test P through innovative agro-engineering of soils, crops and fertilisers would give long-term benefits in reducing the endemic eutrophication risk arising from legacy soil P. Soil P testing should become compulsory in priority catchments suffering, or sensitive to, eutrophication to ensure soil P reserves are fully accounted for as part of good fertiliser and manure management.

  20. Long-term nitrogen fertilization decreased the abundance of inorganic phosphate solubilizing bacteria in an alkaline soil

    DEFF Research Database (Denmark)

    Zheng, Bang-Xiao; Hao, Xiuli; Ding, Kai

    2017-01-01

    Inorganic phosphate solubilizing bacteria (iPSB) are essential to facilitate phosphorus (P) mobilization in alkaline soil, however, the phylogenetic structure of iPSB communities remains poorly characterized. Thus, we use a reference iPSB database to analyze the distribution of iPSB communities...... based on 16S rRNA gene illumina sequencing. Additionally, a noval pqqC primer was developed to quantify iPSB abundance. In our study, an alkaline soil with 27-year fertilization treatment was selected. The percentage of iPSB was 1.10~2.87% per sample, and the dominant iPSB genera were closely related...... to Arthrobacter, Bacillus, Brevibacterium and Streptomyces. Long-term P fertilization had no significant effect on the abundance of iPSB communities. Rather than P and potassium (K) additions, long-term nitrogen (N) fertilization decreased the iPSB abundance, which was validated by reduced relative abundance...

  1. Effects of Long-Term Application of Inorganic Fertilizers on Biochemical Properties of a Rice-Planting Red Soil

    Institute of Scientific and Technical Information of China (English)

    ZHONG Wen-Hui; CAI Zu-Cong; ZHANG He

    2007-01-01

    A long-term experiment was set up in Yingtan of Jiangxi Province to investigate the effects of long-term application of inorganic fertilizers on the biochemical properties of a rice-planting soil derived from Quaternary red earth. Noncultivated soils are extremely eroded and characterized by a low pH and deficiencies in available nutrients, in particular P and N. After 13 years of inorganic fertilization in cultivation for double-cropped rice, the biochemical properties of the soil were changed. The nitrification potential and urease activity were higher in the treatments with N application than those without N application. Acid phosphatase activity and dehydrogenase activity were also higher in the treatments with P application than in those without P application. The dehydrogenase activity correlated well with the concentrations of both total P and hydrolysable N and with rice crop yield, suggesting that dehydrogenase activity might be a suitable indicator for improvement in soil fertility.

  2. Response of soil nematode communities to long-term application of inorganic fertilizers in the black soil of Northeast China

    Institute of Scientific and Technical Information of China (English)

    Xiaoke ZHANG; Yong JIANG; Lei LIANG; Xiaofan ZHAO; Qi LI

    2009-01-01

    The effects of inorganic fertilizers on soil nematode communities were studied in a long-term fertilization experimental field in the Black Soil Region of Northeast China,where no fertilizer (CK),N fertilizer (N),combined application of N and P (NP),combined application of N and K (NK),and combined application of N,P and K (NPK) were compared.The results showed that the total nematode abundance was not affected significantly by inorganic fertilizers in the long-term field experiment.The numbers of bacterivores increased significantly in the NP treatment compared to the CK treatment,and those of fungivores and plant-parasites were inhibited in the NPK treatment.The similarity between CK and NPK treatment and the nematode diversity were higher than in other treatments.The stability of the soil ecosystem was disturbed by the inorganic fertilizers,as indicated by the change in MI values under different treatments.The response of soil nematodes mainly depended on the types of inorganic fertilizers applied.

  3. Changes in cropland topsoil organic carbon with different fertilizations under long-term agro-ecosystem experiments across mainland China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Topsoil soil organic carbon(SOC) data were collected from long-term Chinese agro-ecosystem experiments presented in 76 reports with measurements over 1977 and 2006.The data set comprised 481 observations(135 rice paddies and 346 dry croplands) of SOC under different fertilization schemes at 70 experimental sites(28 rice paddies and 42 dry croplands).The data set covered 16 dominant soil types found in croplands across 23 provinces of mainland China.The fertilization schemes were grouped into six categories:N(inorganic nitrogen fertilizer only),NP(compound inorganic nitrogen and phosphorus fertilizers),NPK(compound inorganic nitrogen,phosphorus and potassium fertilizers),O(organic fertilizers only),OF(combined inorganic/organic fertilization) and Others(other unbalanced fertilizations such as P only,K only,P plus K and N plus K).Relative change in SOC content was analyzed,and rice paddies and dry croplands soils were compared.There was an overall temporal increase in topsoil SOC content,and relative annual change(RAC,g kg-1 yr-1) ranged -0.14-0.60(0.13 on average) for dry cropland soils and -0.12-0.70(0.19 on average) for rice paddies.SOC content increase was higher in rice paddies than in dry croplands.SOC increased across experimental sites,but was higher under organic fertilization and combined organic/inorganic fertilizations than chemical fertilizations.SOC increase was higher under balanced chemical fertilizations with compound N,P and K fertilizers than unbalanced fertilizations such as N only,N plus P,and N plus K.The effects of specific rational fertilizations on SOC increase persisted for 15 years in dry croplands and 20 years in rice paddies,although RAC values decreased generally as the experiment duration increased.Therefore,the extension of rational fertilization in China’s croplands may offer a technical option to enhance C sequestration potential and to sustain long-term crop productivity.

  4. Effects of Long-Term Fertilization on Distribution of Organic Matters and Nitrogen in Cinnamon Soil Macro-Aggregates

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Soil samples collected from a 25-year long-term fertilizer experiment carried out on the Earth-cumulic-Orthic Anthrosols in semi-humid farmland ecological system, were used to study the distribution of soil organic matters, total nitrogen, nitrate nitrogen, and ammoniate nitrogen in different grades of soil macro-aggregates in order to study the effects of long-term application of organic manures in combination with chemical fertilizers. It is showed that the percentage of mass of the soil macro-aggregates with long-term application of fertilizers with sizes of 5-2 mm is increased compared with that of the samples with no fertilizer. It is easier to form lager size soil macro-aggregates by the long-term application of organic manures in combination with chemical fertilizers. The contents of organic matters, total nitrogen and nitrate nitrogen are all higher after treatments with different combinations of fertilizers, while there is a little effect on the contents of ammoniate nitrogen. The contents of organic matters, total nitrogen in the grades of soil macro-aggregates from the plough layers of the treated farmland exhibited significant difference. Moreover, the contents of organic matters and total nitrogen in the soil macro-aggregates with the size of 1-0.25 mm is the highest in all treated soil samples. The contents of nitrate nitrogen in soil macro-aggregates increased with the increasing of soil macro-aggregate size except those applied with chemical fertilizer and lower amount of corn stover. The results of correlation analysis revealed that there exists a significantly positive correlation between the percentage of mass of soil macro-aggregates with the size of 5-2 mm and the contents of organic matters, total nitrogen and nitrate nitrogen in the soil samples. However, the correlation between the percentage of mass of soil macro-aggregates with the size of 1-0.25 mm and the contents of total nitrogen and nitrate nitrogen is significantly negative. The

  5. Quantitative and compositional responses of ammonia-oxidizing archaea and bacteria to long-term field fertilization

    Science.gov (United States)

    Xue, Chao; Zhang, Xu; Zhu, Chen; Zhao, Jun; Zhu, Ping; Peng, Chang; Ling, Ning; Shen, Qirong

    2016-06-01

    Archaeal (AOA) and bacterial (AOB) ammonia-oxidizer responses to long-term field fertilization in a Mollisol soil were assessed through pyrosequencing of amoA genes. Long-term fertilization treatments including chemical fertilizer (NPK), NPK plus manure (NPKM), and no fertilization over 23 years altered soil properties resulting in significant shifts in AOA and AOB community composition and abundance. NPK exhibited a strong influence on AOA and AOB composition while the addition of manure neutralized the community change induced by NPK. NPK also led to significant soil acidification and enrichment of Nitrosotalea. Nitrosospira cluster 9 and 3c were the most abundant AOB populations with opposing responses to fertilization treatments. NPKM had the largest abundance of ammonia-oxidizers and highest potential nitrification activity (PNA), suggesting high N loss potential due to a doubling of nutrient input compared to NPK. PNA was strongly correlated to AOA and AOB community composition indicating that both were important in ammonium oxidization in this Mollisol soil. Total N and organic C were the most important factors driving shifts in AOA and AOB community composition. The AOA community was strongly correlated to the activities of all sugar hydrolysis associated soil enzymes and was more responsive to C and N input than AOB.

  6. Grain yield and crop N offtake in response to residual fertilizer N in long-term field experiments

    DEFF Research Database (Denmark)

    Petersen, Jens; Thomsen, Ingrid Kaag; Mattsson, L.

    2010-01-01

    Organic inputs [e.g. animal manure (AM) and plant residues] contribute directly to the soil organic N pool, whereas mineral N fertilizer contributes indirectly by increasing the return of the crop residues and by microbial immobilization. To evaluate the residual effect of N treatments established...... in four long-term (>35 yr) field experiments, we measured the response of barley (grain yield and N offtake at crop maturity) to six rates (0, 30, 60, 90, 120 and 150 kg N/ha) of mineral fertilizer N (Nnew) applied in subplots replacing the customary long-term plot treatments of fertilizer inputs (Nprev......). Rates of Nprev above 50-100 kg N/ha had no consistent effect on the soil N content, but this was up to 20% greater than that in unfertilized treatments. Long-term unfertilized plots should not be used as control to test the residual value of N in modern agriculture with large production potentials...

  7. Long-term nitrogen fertilization decreased the abundance of inorganic phosphate solubilizing bacteria in an alkaline soil

    Science.gov (United States)

    Zheng, Bang-Xiao; Hao, Xiu-Li; Ding, Kai; Zhou, Guo-Wei; Chen, Qing-Lin; Zhang, Jia-Bao; Zhu, Yong-Guan

    2017-01-01

    Inorganic phosphate solubilizing bacteria (iPSB) are essential to facilitate phosphorus (P) mobilization in alkaline soil, however, the phylogenetic structure of iPSB communities remains poorly characterized. Thus, we use a reference iPSB database to analyze the distribution of iPSB communities based on 16S rRNA gene illumina sequencing. Additionally, a noval pqqC primer was developed to quantify iPSB abundance. In our study, an alkaline soil with 27-year fertilization treatment was selected. The percentage of iPSB was 1.10~2.87% per sample, and the dominant iPSB genera were closely related to Arthrobacter, Bacillus, Brevibacterium and Streptomyces. Long-term P fertilization had no significant effect on the abundance of iPSB communities. Rather than P and potassium (K) additions, long-term nitrogen (N) fertilization decreased the iPSB abundance, which was validated by reduced relative abundance of pqqC gene (pqqC/16S). The decreased iPSB abundance was strongly related to pH decline and total N increase, revealing that the long-term N additions may cause pH decline and subsequent P releases relatively decreasing the demands of the iPSB community. The methodology and understanding obtained here provides insights into the ecology of inorganic P solubilizers and how to manipulate for better P use efficiency. PMID:28181569

  8. Long-term nitrogen fertilization decreased the abundance of inorganic phosphate solubilizing bacteria in an alkaline soil

    Science.gov (United States)

    Zheng, Bang-Xiao; Hao, Xiu-Li; Ding, Kai; Zhou, Guo-Wei; Chen, Qing-Lin; Zhang, Jia-Bao; Zhu, Yong-Guan

    2017-02-01

    Inorganic phosphate solubilizing bacteria (iPSB) are essential to facilitate phosphorus (P) mobilization in alkaline soil, however, the phylogenetic structure of iPSB communities remains poorly characterized. Thus, we use a reference iPSB database to analyze the distribution of iPSB communities based on 16S rRNA gene illumina sequencing. Additionally, a noval pqqC primer was developed to quantify iPSB abundance. In our study, an alkaline soil with 27-year fertilization treatment was selected. The percentage of iPSB was 1.10~2.87% per sample, and the dominant iPSB genera were closely related to Arthrobacter, Bacillus, Brevibacterium and Streptomyces. Long-term P fertilization had no significant effect on the abundance of iPSB communities. Rather than P and potassium (K) additions, long-term nitrogen (N) fertilization decreased the iPSB abundance, which was validated by reduced relative abundance of pqqC gene (pqqC/16S). The decreased iPSB abundance was strongly related to pH decline and total N increase, revealing that the long-term N additions may cause pH decline and subsequent P releases relatively decreasing the demands of the iPSB community. The methodology and understanding obtained here provides insights into the ecology of inorganic P solubilizers and how to manipulate for better P use efficiency.

  9. Transfer of metals in soil-grass ecosystems under long-term N, P, K fertilization in Hesse, Germany

    Science.gov (United States)

    Czarnecki, Sezin; Düring, Rolf-Alexander

    2015-04-01

    With this study focuses on the influence of long-term (14 years) fertilization on metal transition from soil to plants is presented. Accumulation of metals in plants due to long-term fertilization and predicting the bioavailability and transfer of metals in the soil-plant system is of great importance with regard to human health as plants represent the first compartment of the terrestrial food chain. Soil and plant (Lolio-Cynosuretum) samples were taken from a 14 years long-term fertilization field experiment which was carried out in Hesse, Germany. Correlation coefficients, transfer factors, and regression analysis was performed for Cd, Cu, Mn, Pb, and Zn to quantify the relative difference in bioavailability of metals to plants or to identify the capacity of plants to accumulate a given metal. Correlation coefficients between metals in soils and in plants show significant relationships (pCu>Zn>Mn>Pb. Results of stepwise multiple linear regression analysis showed that Corg, CEC and bioavailable metal content are the most important predictors for plant metal uptake.

  10. Crop Yield and Soil Responses to Long-Term Fertilization on a Red Soil in Southern China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hui-Min; WANG Bo-Ren; XU Ming-Gang; FAN Ting-Lu

    2009-01-01

    A 15-year fertilization experiment with different applications of inorganic N,P and K fertilizers and farmyard manure (M) was conducted to study the yield and soil responses to long-term fertilization at Qiyang,Hunan Province,China.Average grain yields of wheat and corn (1 672 and 5 111 kg ha-1,respectively) for the treatment NPKM were significantly higher than those (405 and 310 kg ha-1) of the unfertilized control and single inorganic fertilizer treatments.Compared with the corresponding initial values of the experiment,all treatments showed a yield decline of 9 to 111 kg ha-1 year-1 in wheat and 35 to 260 kg ha-1 year-1 in corn,respectively,and a significant pH decline of 0.07 to 0.12 pH year-1,except for the treatments PK and NPKM.After long-term fertilization,the soil organic C,soil available P,exchangeable Ca2+ and Mg2+ and available Cu2+ and Zn2+ contents were higher in the treatment NPKM than in the treatments applied with inorganic fertilizer only.Compared to the treatment NPK,the treatment NPKM,where manure partially replaced inorganic N,had a positive impact on arresting the decline of soil pH.This improved grain yields of wheat and corn,suggesting that application of NPK fertilizer in combination with farmyard manure is important to maintain soil fertility and buffering capacity in red soil.

  11. Dynamics of Soil and Grain Micronutrients as Affected by Long-Term Fertilization in an Aquic Inceptisol

    Institute of Scientific and Technical Information of China (English)

    LI Ben-Yin; HUANG Shao-Min; WEI Ming-Bao; H.L.ZHANG; SHEN A-Lin; XU Jian-Ming; RUAN Xin-Ling

    2010-01-01

    Micronutrient status in soils can be affected by long-term fertilization and intensive cropping.A 19-year experiment (1990-2008) was carried out to investigate the influence of different fertilization regimes on micronutrients in an Aquic Inceptisol and maize and wheat grains in Zhengzhou,China.The results showed that soil total Cu and Zn markedly declined after 19 years with application of N fertilizer alone.Soil total Fe and Mn were significantly increased mainly due to atmospheric deposition.Applications of P and organic fertilizer with incorporation of straws resulted in dramatic increases in soil total Cu,Zn,Fe,and Mn.Soil diethylenetriamine pentaacetic acid (DTPA)-extractable Cu in all treatments sharply decreased from initially 1.12 to about 0.8 mg kg-1.The treatments with organic fertilizer had the highest soil DTPA-extractable Cu,Zn,Fe,and Mn after 19 years of cropping and fertilization,thus demonstrating the important role of organic fertilizer application in improving available micronutrient status.Cu and Zn contents in wheat grains in the no-P treatments were significantly higher than those of the treatments with P application.In addition,Fe and Mn contents in wheat grains were positively correlated with their soil DTPA-extractable concentrations.These indicated that the long-term application of organic fertilizer resulted in significant increases in soil total and available micronutrient concentrations and remarkable reduction in wheat grain Cu and Zn contents,which was due to high soil available P.

  12. Differential responses of ammonia-oxidizing archaea and bacteria to long-term fertilization in a New England salt marsh

    Directory of Open Access Journals (Sweden)

    Xuefeng ePeng

    2013-01-01

    Full Text Available Since the discovery of ammonia-oxidizing archaea (AOA, new questions have arisen about population and community dynamics and potential interactions between AOA and ammonia-oxidizing Bacteria (AOB. We investigated the effects of long-term fertilization on AOA and AOB in the Great Sippewissett Marsh, Falmouth, MA, USA to address some of these questions. Sediment samples were collected from low and high marsh habitats in July 2009 from replicate plots that received low (LF, high (HF, and extra high (XF levels of a mixed NPK fertilizer biweekly during the growing season since 1974. Additional untreated plots were included as controls (C. Terminal restriction fragment length polymorphism analysis of the amoA genes revealed distinct shifts in AOB communities related to fertilization treatment, but the response patterns of AOA were less consistent. Four AOB operational taxonomic units (OTUs predictably and significantly responded to fertilization, but only one AOA OTU showed a significant pattern. Betaproteobacterial amoA gene sequences within the Nitrosospira-like cluster dominated at C and LF sites, while sequences related to Nitrosomonas spp. dominated at HF and XF sites. We identified some clusters of AOA sequences recovered primarily from high fertilization regimes, but other clusters consisted of sequences recovered from all fertilization treatments, suggesting greater physiological diversity. Surprisingly, fertilization appeared to have little impact on abundance of AOA or AOB. In summary, our data reveal striking patterns for AOA and AOB in response to long-term fertilization, and also suggest a missing link between community composition and abundance and nitrogen processing in the marsh.

  13. Differential responses of ammonia-oxidizing archaea and bacteria to long-term fertilization in a New England salt marsh.

    Science.gov (United States)

    Peng, Xuefeng; Yando, Erik; Hildebrand, Erica; Dwyer, Courtney; Kearney, Anne; Waciega, Alex; Valiela, Ivan; Bernhard, Anne E

    2012-01-01

    Since the discovery of ammonia-oxidizing archaea (AOA), new questions have arisen about population and community dynamics and potential interactions between AOA and ammonia-oxidizing bacteria (AOB). We investigated the effects of long-term fertilization on AOA and AOB in the Great Sippewissett Marsh, Falmouth, MA, USA to address some of these questions. Sediment samples were collected from low and high marsh habitats in July 2009 from replicate plots that received low (LF), high (HF), and extra high (XF) levels of a mixed NPK fertilizer biweekly during the growing season since 1974. Additional untreated plots were included as controls (C). Terminal restriction fragment length polymorphism analysis of the amoA genes revealed distinct shifts in AOB communities related to fertilization treatment, but the response patterns of AOA were less consistent. Four AOB operational taxonomic units (OTUs) predictably and significantly responded to fertilization, but only one AOA OTU showed a significant pattern. Betaproteobacterial amoA gene sequences within the Nitrosospira-like cluster dominated at C and LF sites, while sequences related to Nitrosomonas spp. dominated at HF and XF sites. We identified some clusters of AOA sequences recovered primarily from high fertilization regimes, but other clusters consisted of sequences recovered from all fertilization treatments, suggesting greater physiological diversity. Surprisingly, fertilization appeared to have little impact on abundance of AOA or AOB. In summary, our data reveal striking patterns for AOA and AOB in response to long-term fertilization, and also suggest a missing link between community composition and abundance and nitrogen processing in the marsh.

  14. Long-term effect of manure and fertilizer on soil organic carbon pools in dryland farming in northwest China.

    Science.gov (United States)

    Liu, Enke; Yan, Changrong; Mei, Xurong; Zhang, Yanqing; Fan, Tinglu

    2013-01-01

    An understanding of the dynamics of soil organic carbon (SOC) as affected by farming practices is imperative for maintaining soil productivity and mitigating global warming. The objectives of this study were to investigate the effects of long-term fertilization on SOC and SOC fractions for the whole soil profile (0-100 cm) in northwest China. The study was initiated in 1979 in Gansu, China and included six treatments: unfertilized control (CK), nitrogen fertilizer (N), nitrogen and phosphorus (P) fertilizers (NP), straw plus N and P fertilizers (NP+S), farmyard manure (FYM), and farmyard manure plus N and P fertilizers (NP+FYM). Results showed that SOC concentration in the 0-20 cm soil layer increased with time except in the CK and N treatments. Long-term fertilization significantly influenced SOC concentrations and storage to 60 cm depth. Below 60 cm, SOC concentrations and storages were statistically not significant between all treatments. The concentration of SOC at different depths in 0-60 cm soil profile was higher under NP+FYM follow by under NP+S, compared to under CK. The SOC storage in 0-60 cm in NP+FYM, NP+S, FYM and NP treatments were increased by 41.3%, 32.9%, 28.1% and 17.9%, respectively, as compared to the CK treatment. Organic manure plus inorganic fertilizer application also increased labile soil organic carbon pools in 0-60 cm depth. The average concentration of particulate organic carbon (POC), dissolved organic carbon (DOC) and microbial biomass carbon (MBC) in organic manure plus inorganic fertilizer treatments (NP+S and NP+FYM) in 0-60 cm depth were increased by 64.9-91.9%, 42.5-56.9%, and 74.7-99.4%, respectively, over the CK treatment. The POC, MBC and DOC concentrations increased linearly with increasing SOC content. These results indicate that long-term additions of organic manure have the most beneficial effects in building carbon pools among the investigated types of fertilization.

  15. Long-term effect of manure and fertilizer on soil organic carbon pools in dryland farming in northwest China.

    Directory of Open Access Journals (Sweden)

    Enke Liu

    Full Text Available An understanding of the dynamics of soil organic carbon (SOC as affected by farming practices is imperative for maintaining soil productivity and mitigating global warming. The objectives of this study were to investigate the effects of long-term fertilization on SOC and SOC fractions for the whole soil profile (0-100 cm in northwest China. The study was initiated in 1979 in Gansu, China and included six treatments: unfertilized control (CK, nitrogen fertilizer (N, nitrogen and phosphorus (P fertilizers (NP, straw plus N and P fertilizers (NP+S, farmyard manure (FYM, and farmyard manure plus N and P fertilizers (NP+FYM. Results showed that SOC concentration in the 0-20 cm soil layer increased with time except in the CK and N treatments. Long-term fertilization significantly influenced SOC concentrations and storage to 60 cm depth. Below 60 cm, SOC concentrations and storages were statistically not significant between all treatments. The concentration of SOC at different depths in 0-60 cm soil profile was higher under NP+FYM follow by under NP+S, compared to under CK. The SOC storage in 0-60 cm in NP+FYM, NP+S, FYM and NP treatments were increased by 41.3%, 32.9%, 28.1% and 17.9%, respectively, as compared to the CK treatment. Organic manure plus inorganic fertilizer application also increased labile soil organic carbon pools in 0-60 cm depth. The average concentration of particulate organic carbon (POC, dissolved organic carbon (DOC and microbial biomass carbon (MBC in organic manure plus inorganic fertilizer treatments (NP+S and NP+FYM in 0-60 cm depth were increased by 64.9-91.9%, 42.5-56.9%, and 74.7-99.4%, respectively, over the CK treatment. The POC, MBC and DOC concentrations increased linearly with increasing SOC content. These results indicate that long-term additions of organic manure have the most beneficial effects in building carbon pools among the investigated types of fertilization.

  16. Long-term fertilization of a boreal Norway spruce forest increases the temperature sensitivity of soil organic carbon mineralization.

    Science.gov (United States)

    Coucheney, Elsa; Strömgren, Monika; Lerch, Thomas Z; Herrmann, Anke M

    2013-12-01

    Boreal ecosystems store one-third of global soil organic carbon (SOC) and are particularly sensitive to climate warming and higher nutrient inputs. Thus, a better description of how forest managements such as nutrient fertilization impact soil carbon (C) and its temperature sensitivity is needed to better predict feedbacks between C cycling and climate. The temperature sensitivity of in situ soil C respiration was investigated in a boreal forest, which has received long-term nutrient fertilization (22 years), and compared with the temperature sensitivity of C mineralization measured in the laboratory. We found that the fertilization treatment increased both the response of soil in situ CO2 effluxes to a warming treatment and the temperature sensitivity of C mineralization measured in the laboratory (Q10). These results suggested that soil C may be more sensitive to an increase in temperature in long-term fertilized in comparison with nutrient poor boreal ecosystems. Furthermore, the fertilization treatment modified the SOC content and the microbial community composition, but we found no direct relationship between either SOC or microbial changes and the temperature sensitivity of C mineralization. However, the relation between the soil C:N ratio and the fungal/bacterial ratio was changed in the combined warmed and fertilized treatment compared with the other treatments, which suggest that strong interaction mechanisms may occur between nutrient input and warming in boreal soils. Further research is needed to unravel into more details in how far soil organic matter and microbial community composition changes are responsible for the change in the temperature sensitivity of soil C under increasing mineral N inputs. Such research would help to take into account the effect of fertilization managements on soil C storage in C cycling numerical models.

  17. Wheat Grain Yield and Yield Stability in a Long-Term Fertilization Experiment on the Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    HAO Ming-De; FAN Jun; WANG Quan-Jiu; DANG Ting-Hui; GUO Sheng-Li; WANG Ji-Jun

    2007-01-01

    To provide a scientific basis for sustainable land management,a 20-year fertility experiment Was conducted in Changwu County,Shaanxi Province,China to investigate the effects of long-term application of chemical fertilizers on wheat grain yield and yield stability on the Loess Plateau using regression and stability analysis.The experiment consisted of 17fertilizer treatments.containing the combinations of different N and P levels,with three replications arranged in a randomized complete block design.Nitrogen fertilizer was applied as urea,and P was applied as calcium superphosphate.Fertilizer rates had a large effect on the response of wheat yield to fertilization.Phosphorus,combined with N,increased yield significantly(P≤0.01).In the unfertilized control and the N or P sole application treatments,wheat yield had a declining trend although it was not statistically significant.Stability analysis combined with the trend analysis indicated that integrated use of fertilizer N and P was better than their sole application in increasing and sustaining the productivity of rainfed winter wheat.

  18. Basic Soil Productivity of Spring Maize in Black Soil Under Long-Term Fertilization Based on DSSAT Model

    Institute of Scientific and Technical Information of China (English)

    ZHA Yan; WU Xue-ping; HE Xin-hua; ZHANG Hui-min; GONG Fu-fei; CAI Dian-xiong; ZHU Ping; GAO Hong-jun

    2014-01-01

    Increasing basic farmland soil productivity has signiifcance in reducing fertilizer application and maintaining high yield of crops. In this study, we deifned that the basic soil productivity (BSP) is the production capacity of a farmland soil with its own physical and chemical properties for a speciifc crop season under local environment and ifeld management. Based on 22-yr (1990-2011) long-term experimental data on black soil (Typic hapludoll) in Gongzhuling, Jilin Province, Northeast China, the decision support system for an agro-technology transfer (DSSAT)-CERES-Maize model was applied to simulate the yield by BSP of spring maize (Zea mays L.) to examine the effects of long-term fertilization on changes of BSP and explore the mechanisms of BSP increasing. Five treatments were examined:(1) no-fertilization control (control);(2) chemical nitrogen, phosphorus, and potassium (NPK); (3) NPK plus farmyard manure (NPKM); (4) 1.5 time of NPKM (1.5NPKM) and (5) NPK plus straw (NPKS). Results showed that after 22-yr fertilization, the yield by BSP of spring maize signiifcantly increased 78.0, 101.2, and 69.4% under the NPKM, 1.5NPKM and NPKS, respectively, compared to the initial value (in 1992), but not signiifcant under NPK (26.9%increase) and the control (8.9%decrease). The contribution percentage of BSP showed a signiifcant rising trend (PNPKM>NPK≈NPKS, indicating that organic manure combined with chemical fertilizers (1.5NPKM and NPKM) could more effectively increase BSP compared with the inorganic fertilizer application alone (NPK) in the black soil. This study showed that soil organic matter (SOM) was the key factor among various fertility factors that could affect BSP in the black soil, and total N, total P and/or available P also played important role in BSP increasing. Compared with the chemical fertilization, a balanced chemical plus manure or straw fertilization (NPKM or NPKS) not only increased the concentrations of soil nutrient, but also improved the

  19. Effects of soil biota influenced by long-term organic and chemical fertilizers on rice growth and resistance to insects

    Directory of Open Access Journals (Sweden)

    Linhui Jiang

    2016-08-01

    Full Text Available Fertilization plays an important role in soil quality, food supply and security. Although promoting soil biological development is considered as one of the most critical components that organic fertilizers exert on soil compared with chemical fertilization, less attention has been paid to the fertilization-derived influence on crop growth and insect-resistance via soil biota. Understanding the role of soil biota in crop growth and resistance to insects would not only help explain the biological mechanisms of the fertilization effects on soil functions, but also help identify integrative management techniques for soils and crops. Soil suspension was extracted from long-term organically fertilized soils and chemically fertilized soils. Then, the soil suspension was sterilized or non-sterilized to investigate the soil biota’s effects on rice growth and insect-resistance through a soil-free cultured method. Results showed that soil biota and fertilization significantly affected soil nutrient status (P < 0.01. Soil biota decreased soil ammonium content, rice biomass, shoot nitrogen content and the biomass of Nilaparvata lugens, but increased soil nitrate content, rice root-shoot ratio and the contents of root nitrogen, soluble sugar and phenolics (P < 0.05. Meanwhile, soil biota from organically fertilized soils promoted the synthesis of shoot soluble sugar and shoot phenolics. With the addition of Nilaparvata lugens, soil biota significantly reduced rice nitrogen uptake and promoted phenolic synthesis (P < 0.05. Collectively, soil biota, especially from organically fertilized soils, promoted rice resistance traits by altering the nutrient allocation of rice between aboveground and belowground, and by increasing the root-shoot ratio and the synthesis of phenols.

  20. [Dynamics of microbial biomass C in a black soil under long-term fertilization and related affecting factors].

    Science.gov (United States)

    Li, Dongpo; Wu, Zhijie; Chen, Lijun; Zhu, Ping; Ren, Jun; Peng, Chang; Liang, Chenghua

    2004-08-01

    The effect of long-term fertilization on the dynamics of microbial biomass C in a typical black soil of Northeastern China was studied in a field trail treated by different fertilizations. The results showed that the amount of soil microbial biomass C under different fertilizations varied significantly with growth stages. It was the highest in farmyard manure (M2 and M4) treatments, with a less seasonal fluctuation, second in NPK treatment, the peak at sowing period, and the lowest in CK, the peak at wax maturity stage. No significant correlation was found between the dynamic changes of soil microbial biomass C and soil biological, physical and chemical properties in all treatments, but the correlation of soil microbial biomass C with the contents of N, P and K in plants and that of crude protein in grain was significantly positive.

  1. The effects of long-term fertilization on the temporal stability of alpine meadow communities

    NARCIS (Netherlands)

    Yang, Z.; Ruijven, van J.; Du, G.

    2011-01-01

    The aim of the study was to investigate how plant species’ composition, soil parameters and nutrient concentrations in plant biomass differ between fertilized and control plots 62 years after the last fertilizer application on a sub-alpine grassland. A piece of land called the Grass Garden (GG), fer

  2. Bacterial community structure and diversity in a black soil as affected by long-term fertilization

    Institute of Scientific and Technical Information of China (English)

    WEI Dan; YANG Qian; ZHANG Jun-Zheng; WANG Shuang; CHEN Xue-Li; ZHANG Xi-Lin; LI Wei-Qun

    2008-01-01

    Black soil (Mollisol) is one of the main soil types in northeastern China.Biolog and polymerase chain reactiondenaturing gradient gel electrophoresis (PCR-DGGE) methods were used to examine the influence of various fertilizer combinations on the structure and function of the bacterial community in a black soil collected from Harbin,Heilongjiang Province.Biolog results showed that substrate richness and catabolic diversity of the soil bacterial community were the greatest in the chemical fertilizer and chemical fertilizer+manure treatments.The metabolic ability of the bacterial community in the manure treatment was similar to the control.DGGE fingerprinting indicated similarity in the distribution of most 16S rDNA bands among all treatments,suggesting that microorganisms with those bands were stable and not influenced by fertilization.However,chemical fertilizer increased the diversity of soil bacterial community.Principal component analysis of Biolog and DGGE data revealed that the structure and function of the bacterial community were similar in the control and manure treatments,suggesting that the application of manure increased the soil microbial population,but had no effect on the bacterial community structure.Catabolic function was similar in the chemical fertilizer and chemical fertilizer+manure treatments,but the composition structure of the soil microbes differed between them.The use of chemical fertilizers could result in a decline in the catabolic activity of fast-growing or eutrophic bacteria.

  3. Effects of long-term nitrogen fertilization on the uptake kinetics of atmospheric methane in temperate forest soils.

    Science.gov (United States)

    Gulledge, Jay; Hrywna, Yarek; Cavanaugh, Colleen; Steudler, Paul A

    2004-09-01

    To determine whether repeated, long-term NH(4) (+) fertilization alters the enzymatic function of the atmospheric CH(4) oxidizer community in soil, we examined CH(4) uptake kinetics in temperate pine and hardwood forest soils amended with 150 kg N ha(-1) y(-1) as NH(4)NO(3) for more than a decade. The highest rates of atmospheric CH(4) consumption occurred in the upper 5 cm mineral soil of the control plots. In contrast to the results of several previous studies, surface organic soils in the control plots also exhibited high consumption rates. Fertilization decreased in situ CH(4) consumption in the pine and hardwood sites relative to the control plots by 86% and 49%, respectively. Fertilization increased net N mineralization and relative nitrification rates and decreased CH(4) uptake most dramatically in the organic horizon, which contributed substantially to the overall decrease in field flux rates. In all cases, CH(4) oxidation followed Michaelis-Menten kinetics, with apparent K(m) (K(m(app))) values typical of high-affinity soil CH(4) oxidizers. Both K(m(app)) and V(max(app)) were significantly lower in fertilized soils than in unfertilized soils. The physiology of the methane consumer community in the fertilized soils was distinct from short-term responses to NH(4) (+) addition. Whereas the immediate response to NH(4) (+) was an increase in K(m(app)), resulting from apparent enzymatic substrate competition, the long-term response to fertilization was a community-level shift to a lower K(m(app)), a possible adaptation to diminish the competitiveness of NH(4) (+) for enzyme active sites.

  4. Nitrous oxide emission from highland winter wheat field after long-term fertilization

    Directory of Open Access Journals (Sweden)

    X. R. Wei

    2010-10-01

    Full Text Available Nitrous oxide (N2O is an important greenhouse gas. N2O emissions from soils vary with fertilization and cropping practices. The response of N2O emission to fertilization of agricultural soils plays an important role in global N2O emission. The objective of this study was to assess the seasonal pattern of N2O fluxes and the annual N2O emissions from a rain-fed winter wheat (Triticum aestivum L. field in the Loess Plateau of China. A static flux chamber method was used to measure soil N2O fluxes from 2006 to 2008. The study included 5 treatments with 3 replications in a randomized complete block design. Prior to initiating N2O measurements the treatments had received the same fertilization for 22 years. The fertilizer treatments were unfertilized control (CK, manure (M, nitrogen (N, nitrogen + phosphorus (NP, and nitrogen + phosphorus + manure (NPM. Soil N2O fluxes in the highland winter wheat field were highly variable temporally and thus were fertilization dependent. The highest fluxes occurred in the warmer and wetter seasons. Relative to CK, m slightly increased N2O flux while N, NP and NPM treatments significantly increased N2O fluxes. The fertilizer induced increase in N2O flux occurred mainly in the first 30 days after fertilization. The increases were smaller in the relatively warm and dry year than in the cold and wet year. Combining phosphorous and/or manure with mineral N fertilizer partly offset the nitrogen fertilizer induced increase in N2O flux. N2O fluxes at the seedling stage were mainly controlled by nitrogen fertilization, while fluxes at other plant growth stages were influenced by plant and environmental conditions. The cumulative N2O emissions were always higher in the fertilized treatments than in the non-fertilized treatment (CK. Mineral and manure

  5. Nitrous oxide emission from highland winter wheat field after long-term fertilization

    Directory of Open Access Journals (Sweden)

    X. R. Wei

    2010-06-01

    Full Text Available Nitrous oxide (N2O is an important greenhouse gas. N2O emissions from soils vary with fertilization and cropping practices. The response of N2O emission to fertilization of agricultural soils plays an important role in global N2O emission. The objective of this study was to assess the seasonal pattern of N2O fluxes and the annual N2O emissions from a rain-fed winter wheat (Triticum aestivum L. field in the Loess Plateau of China. A static flux chamber method was used to measure soil N2O fluxes from 2006 to 2008. The study included 5 treatments with 3 replications in a randomized complete block design. Prior to initiating N2O measurements the treatments had received the same fertilization for 22 years. The fertilizer treatments were unfertilized control (CK, manure (M, nitrogen (N, nitrogen + phosphorus (NP, and nitrogen + phosphorus + manure (NPM. Soil N2O fluxes in the highland winter wheat field were highly variable temporally and thus were fertilization dependent. The highest fluxes occurred in the warmer and wetter seasons. Relative to CK, M slightly increased N2O flux while N, NP and NPM treatments significantly increased N2O fluxes. The fertilizer induced increase in N2O flux occurred mainly in the first 30 days after fertilization. The increases were smaller in the relatively warm and dry year than in the cold and wet year. Combining phosphorous and/or manure with mineral N fertilizer partly offset the nitrogen fertilizer induced increase in N2O flux. N2O fluxes at the seedling stage were mainly controlled by nitrogen fertilization, while fluxes at other plant growth stages were influenced by plant and environmental conditions. The cumulative N2O emissions were always higher in the fertilized treatments than in the non-fertilized treatment (CK. Mineral and manure

  6. [Effects of different long-term fertilization patterns on Fuji apple yield, quality, and soil fertility on Weibei Dryland, Shaanxi Province of Northwest China].

    Science.gov (United States)

    Zhao, Zuo-Ping; Tong, Yan-An; Liu, Fen; Wang, Xiao-Ying

    2013-11-01

    A 7-year (2003-2010) located field experiment was conducted to evaluate the effects of different long-term fertilization patterns on the Fuji apple yield, quality, and soil fertility on the Weibei Dryland, Shaanxi Province of Northwest China. Seven treatments were installed, i. e., no fertilization (CK), inorganic P and K fertilization (PK), inorganic N and K fertilization (NK), inorganic N and P fertilization (NP), inorganic N, P, and K fertilization (NPK), swine manure (M), and half inorganic N, P, and K combined with half swine manure (NPKM). Each treatment had three replications. Fertilization increased the apple yield. The average yield in the 7 years under fertilization was increased by 14.4%-63.8%, as compared to the CK. The average yield decreased in the order of NPKM > NPK > or = M > NP > or = NK > PK > CK. In treatments NPKM, M, and NPK, the fruit sugar/acid (S:A) ratio, vitamin C, soluble solid, and hardness tended to be increased with time, with a smaller yearly fluctuation in treatments NPKM and M. In treatment NPKM, the S:A ratio and vitamin C increased by 30.9% and 17.5%, respectively after five years, as compared to the CK. Long-term rational fertilization increased the soil organic matter (SOC) content in 0-20 cm layer, with the largest increment in treatments NPKM and M (28.8% and 29.3%, respectively). The soil available N, P, and K contents in all layers in treatments NPK, NPKM, and M increased significantly, and the soil available N content in 0-20, 20-40, and 40-60 cm layers in treatment NPK was increased by 22.7%, 37.3%, and 53.4%, respectively. As compared to treatment NPK, the soil available P content in treatment NPKM was increased by 18.7%. In all fertilization treatments, the soil available Pcontent was significantly higher in upper layer than in lower layer.

  7. Modelling crop yield, soil organic C and P under variable long-term fertilizer management in China

    Science.gov (United States)

    Zhang, Jie; Xu, Guang; Xu, Minggang; Balkovič, Juraj; Azevedo, Ligia B.; Skalský, Rastislav; Wang, Jinzhou; Yu, Chaoqing

    2016-04-01

    Phosphorus (P) is a major limiting nutrient for plant growth. P, as a nonrenewable resource and the controlling factor of aquatic entrophication, is critical for food security and human future, and concerns sustainable resource use and environmental impacts. It is thus essential to find an integrated and effective approach to optimize phosphorus fertilizer application in the agro-ecosystem while maintaining crop yield and minimizing environmental risk. Crop P models have been used to simulate plant-soil interactions but are rarely validated with scattered long-term fertilizer control field experiments. We employed a process-based model named Environmental Policy Integrated Climate model (EPIC) to simulate grain yield, soil organic carbon (SOC) and soil available P based upon 8 field experiments in China with 11 years dataset, representing the typical Chinese soil types and agro-ecosystems of different regions. 4 treatments, including N, P, and K fertilizer (NPK), no fertilizer (CK), N and K fertilizer (NK) and N, P, K and manure (NPKM) were measured and modelled. A series of sensitivity tests were conducted to analyze the sensitivity of grain yields and soil available P to sequential fertilizer rates in typical humid, normal and drought years. Our results indicated that the EPIC model showed a significant agreement for simulating grain yields with R2=0.72, index of agreement (d)=0.87, modeling efficiency (EF)=0.68, pmanagement practices.

  8. [Effects of long-term fertilization on pH buffer system of sandy loam calcareous fluvor-aquic soil].

    Science.gov (United States)

    Wang, Ji-Dong; Qi, Bing-Jie; Zhang, Yong-Chun; Zhang, Ai-Jun; Ning, Yun-Wang; Xu, Xian-Ju; Zhang, Hui; Ma, Hong-Bo

    2012-04-01

    Soil samples (0-80 cm) were collected from a 30-year fertilization experimental site in Xuzhou, Jiangsu Province of East China to study the variations of the pH, calcium carbonate and active calcium carbonate contents, and pH buffer capacity of sandy loam calcareous fluvor-aquic soil under different fertilization treatments. Thirty-year continuous application of different fertilizers accelerated the acidification of topsoil (0-20 cm), with the soil pH decreased by 0.41-0.70. Under different fertilization, the soil pH buffer capacity (pHBC) varied from 15.82 to 21.96 cmol x kg(-1). As compared with no fertilization, single N fertilization decreased the pHBC significantly, but N fertilization combined with organic fertilization could significantly increase the pHBC. The soil pHBC had significant positive correlations with soil calcium carbonate and active calcium carbonate contents, but less correlation with soil organic matter content and soil cation exchange capacity, suggesting that after a long-term fertilization, the sandy loam calcareous fluvor-aquic soil was still of an elementary calcium carbonate buffer system, and soil organic matter and cation exchange capacity contributed little to the buffer system. The soil calcium carbonate and active calcium carbonate contents were greater in 0-40 cm than in 40-80 cm soil layer. Comparing with soil calcium carbonate, soil active calcium carbonate was more sensitive to reflect the changes of soil physical and chemical properties, suggesting that the calcium carbonate buffer system could be further classified as soil active calcium carbonate buffer system.

  9. Responses of absolute and specific soil enzyme activities to long term additions of organic and mineral fertilizer.

    Science.gov (United States)

    Zhang, Xinyu; Dong, Wenyi; Dai, Xiaoqin; Schaeffer, Sean; Yang, Fengting; Radosevich, Mark; Xu, Lili; Liu, Xiyu; Sun, Xiaomin

    2015-12-01

    Long-term phosphorus (P) and nitrogen (N) applications may seriously affect soil microbial activity. A long-term field fertilizer application trial was established on reddish paddy soils in the subtropical region of southern China in 1998. We assessed the effects of swine manure and seven different rates or ratios of NPK fertilizer treatments on (1) the absolute and specific enzyme activities per unit of soil organic carbon (SOC) or microbial biomass carbon (MBC) involved in C, N, and P transformations and (2) their relationships with soil environmental factors and soil microbial community structures. The results showed that manure applications led to increases in the absolute and specific activities of soil β-1,4-glucosidase(βG), β-1,4-N-acetylglucosaminidase (NAG), and leucine aminopeptidase (LAP). The absolute and specific acid phosphatase (AP) activities decreased as mineral P fertilizer application rates and ratios increased. Redundancy analysis (RDA) showed that there were negative correlations between absolute and specific AP activities, pH, and total P contents, while there were positive correlations between soil absolute and specific βG, NAG, and LAP enzyme activities, and SOC and total N contents. RDA showed that the contents of actinomycete and Gram-positive bacterium PLFA biomarkers are more closely related to the absolute and specific enzyme activities than the other PLFA biomarkers (Pfertilizer application rates to subtropical paddy soils should not exceed 44 kg P ha(-1) year(-1).

  10. Changes in Organic Carbon Index of Grey Desert Soil in Northwest China After Long-Term Fertilization

    Institute of Scientific and Technical Information of China (English)

    XU Yong-mei; LIU Hua; WANG Xi-he; XU Ming-gang; ZHANG Wen-ju; JIANG Gui-ying

    2014-01-01

    Soil organic carbon (SOC), soil microbial biomass carbon (SMBC) and SMBC quotient (SMBC/SOC, qSMBC) are key indexes of soil biological fertility because of the relationship to soil nutrition supply capacity. Yet it remains unknown how these three indexes change, which limits our understanding about how soil respond to different fertilization practices. Based on a 22-yr (1990-2011) long-term fertilization experiment in northwest China, we investigated the dynamics of SMBC and qSMBC during the growing period of winter wheat, the relationships between the SMBC, qSMBC, soil organic carbon (SOC) concentrations, the carbon input and grain yield of wheat as well. Fertilization treatments were 1) nonfertilization (control);2) chemical nitrogen plus phosphate plus potassium (NPK);3) NPK plus animal manure (NPKM);4) double NPKM (hNPKM) and 5) NPK plus straw (NPKS). Results showed that the SMBC and qSMBC were signiifcantly different among returning, jointing, lfowering and harvest stages of wheat under long-term fertilization. And the largest values were observed in the lfowering stage. Values for SMBC and qSMBC ranged from 37.5 to 106.0 mg kg-1 and 0.41 to 0.61%, respectively. The mean value rank of SMBC during the whole growing period of wheat was hNPKM>NPKM>NPKS>CK>NPK. But there were no statistically signiifcant differences between hNPKM and NPKM, or between CK and NPK. The order for qSMBC was NPKS>NPKM>CK>hNPKM>NPK. These results indicated that NPKS signiifcantly increased the ratio of SMBC to SOC, i.e., qSMBC, compared with NPK fertilizer or other two NPKM fertilizations. Signiifcant linear relationships were observed between the annual carbon input and SOC (P<0.01) or SMBC (P<0.05), and between the relative grain yield of wheat and the SOC content as well (P<0.05). But the qSMBC was not correlated with the annual carbon input. It is thus obvious that the combination of manure, straw with mineral fertilizer may be beneift to increase SOC and improve soil quality than

  11. Multi-configuration electromagnetic induction measurements at long term agricultural test sites in Germany with different fertilizer and irrigation managements

    Science.gov (United States)

    Kaufmann, Manuela Sarah; von Hebel, Christian; Brogi, Cosimo; Baumecker, Michael; Döring, Thomas; Amelung, Wulf; Vereecken, Harry; van der Kruk, Jan

    2017-04-01

    Electromagnetic induction (EMI) data are often being used to investigate large scale soil properties including clay content, soil water content, and salinity changes for a wide range of applications. For agricultural sites, different management practices such as organic/mineral fertilization, tillage, and/or irrigation are important when interpreting the measured apparent electrical conductivity (ECa). Here, we present EMI data recorded at two long term field experiment (LTFE) agricultural test sites in Thyrow near Berlin (Germany), where different long term fertilizer and irrigation management practices were applied. We used two fixed-boom multi-coil EMI instruments that simultaneously measure over nine different depths of investigation (DOI), recording information ranging between the very shallow (0-0.25 m) ploughing zone including the organic matter and the surface soil (A-Horizon) down to the relatively deep (0-2.7 m) subsoil (B-Horizon) or even substratum (C-Horizon). At both test sites, the prevailing sandy to silty sand in the A- and B-Horizon is underlain by a glacial till C-Horizon resulting in generally low ECa values between 0.5 and 5 mS/m. At one test site, a "static nutrient deficiency experiment" is performed since 1937, where organic fertilizer (farm yard manure) and mineral fertilizers (nitrogen-phosphate-potassium (NPK) and liming) are applied at specific grids. Comparing the fertilizer application grid to the measured EMI data, the lowest ECa values coincide to unfertilized grids whereas the ECa values increase with liming, farm yard manure, and NPK. The visually observed correlation between ECa and the liming treatment was possibly due to the increased pH of the soil, because the fertilizer application increases ion contents that increase the soil electrical conductivity. At the second test site, a "Static Irrigation and Fertilizer Experiment" is conducted, where next to the fertilizer treatment (farm yard manure and nitrogen) part of the field

  12. Long-term organic and inorganic fertilizations enhanced basic soil productivity in a lfuvo-aquic soil

    Institute of Scientific and Technical Information of China (English)

    ZHA Yan; WU Xue-ping; GONG Fu-fei; XU Ming-gang; ZHANG Hui-min; CHEN Li-ming; HUANG Shao-min; CAI Dian-xiong

    2015-01-01

    The improvement of soil productivity depends on a rational input of water and nutrients, optimal ifeld management, and the increase of basic soil productivity (BSP). In this study, BSP is deifned as the productive capacity of a farmland soil with its own physical and chemical properties for a speciifc crop season under local ifeld management. Based on 19-yr data of the long-term agronomic experiments (1989–2008) on a lfuvo-aquic soil in Zhengzhou, Henan Province, China, the decision support system for agrotechnology transfer (DSSAT ver. 4.0) crop growth model was used to simulate yields by BSP of winter wheat (Triticum aestiviumL.) and summer maize (Zea maysL.) to examine the relationship between BSP and soil organic carbon (SOC) under long-term fertilization. Five treatments were included: (1) no fertilization (control), (2) nitrogen, phosphorus and potassium fertilizers (NPK), (3) NPK plus manure (NPKM), (4) 1.5 times of NPKM (1.5NPKM), and (5) NPK plus straw (NPKS). After 19 yr of treatments, the SOC stock increased 16.7, 44.2, 69.9, and 25.2% under the NPK, NPKM, 1.5NPKM, and NPKS, respectively, compared to the initial value. Among various nutrient factors affecting contribution per-centage of BSP to winter wheat and summer maize, SOC was a major affecting factor for BSP in the lfuvo-aquic soil. There were signiifcant positive correlations between SOC stock and yields by BSP of winter wheat and summer maize (P<0.01), and yields by BSP of winter wheat and summer maize increased 154 and 132 kg ha–1 when SOC stock increased 1 t C ha–1. Thus, increased SOC accumulation is a crucial way for increasing BSP in lfuvo-aquic soil.The manure or straw combined application with chemical fertilizers signiifcantly enhanced BSP compared to the application of chemical fertilizers alone.

  13. [Responses of soil nematode communities to long-term application of inorganic fertilizers in upland red soil].

    Science.gov (United States)

    Zhang, Wei; Liu, Man-Qiang; He, Yuan-Qiu; Fan, Jian-Bo; Chen, Yan

    2014-08-01

    Soil biota plays a key role in ecosystem functioning of red soil. Based on the long-term inorganic fertilization field experiment (25-year) in an upland red soil, the impacts of different inorganic fertilization managements, including NPK (nitrogen, phosphorus and potassium fertilizers), NPKCaS (NPK plus gypsum fertilizers), NP (nitrogen and phosphorus fertilizers), NK (nitrogen and potassium fertilizers) and PK (phosphorus and potassium fertilizers), on the assemblage of soil nematodes during the growing period of peanut were investigated. Significant differences among the treatments were observed for total nematode abundance, trophic groups and ecological indices (P NPKCaS > NPK > NP > NK. The total number of nematodes was significantly higher in NPKCaS and PK than in NPK, NP and NK except in May. Plant parasitic nematodes were the dominant trophic group in all treatments excepted in NPKCaS, and their proportion ranged between 38% and 65%. The dominant trophic group in NPKCaS was bacterivores and represented 42.1%. Furthermore, the higher values of maturity index, Wasilewska index and structure index in NPKCaS indicated that the combined application of NPK and gypsum could remarkably relieve soil acidification, resulting in a more mature and stable soil food web structure. While, that of the NK had the opposite effect. In conclusion, our study suggested that the application of both gypsum and phosphate is an effective practice to improve soil quality. Moreover, the analysis of nematode assemblage is relevant to reflect the impact of different inorganic fertilizer on the red soil ecosystem.

  14. N Mineralization as Affected by Long-Term N Fertilization and Its Relationship with Crop N Uptake

    Institute of Scientific and Technical Information of China (English)

    YAN De-Zhi; WANG De-Jian; SUN Rui-Juan; LIN Jing-Hui

    2006-01-01

    A field experiment established in 1997 was conducted to study the effect of long-term N fertilizer application on N mineralization in a paddy soil determined using a laboratory anaerobic incubation followed with a field incubation and to measure the relationship between in situ N mineralization and crop N uptake. To estimate N mineralization in the laboratory, soil samples were collected from plots with N application at different rates for six years and were incubated.Soils treated with fertilizer N mineralized more N than unfertilized soils and mineralization increased with N application rates. Also, the fraction of total N mineralized increased with increasing N fertilizer application. These findings meant that a substantial portion of previously applied N could be recovered slowly over time in subsequent crops. The field incubation of the plot receiving no fertilizer N showed that the NH4+-N concentration varied greatly during the rice-growing season and seasonal changes of N mineralization were due more to accumulation of NH4+-N than NO3--N. Rice N uptake increased up to a maximum of 82 kg N ha-1 during the season. The close agreement found between in situ N mineralization and rice N uptake suggested that the measurement of in situ N mineralization could provide useful recommendations for adequate fertilizer N application.

  15. [Change characteristics of rice yield and soil organic matter and nitrogen contents under various long-term fertilization regimes].

    Science.gov (United States)

    Huang, Jing; Gao, Ju-Sheng; Zhang, Yang-Zhu; Qin, Dao-Zhu; Xu, Ming-Gang

    2013-07-01

    A long-term (1982-2010) field experiment was conducted in the Red Soil Experiment Station of Chinese Academy of Agricultural Sciences in Qiyang County of Hunan Province, South-central China to investigate the dynamic changes of rice yield and soil organic matter (OM) and nitrogen contents under different fertilization treatments. The treatments included NPK, NPKM (M: manure), NPM, NKM, PKM, M, and CK. Fertilization increased the soil OM, total N, and alkaline-hydrolysable N contents and the rice yield. In treatment NPKM, the rice yield across the 28 years maintained at the highest level; while in treatment NPK, the yield showed a decreasing trend, being lower than that in other fertilization treatments. In the treatments applied with manure only or in combining with chemical fertilizers, the soil OM content increased rapidly in the first 16 years, and then fluctuated around a constant level (29.42-39.32 g x kg(-1)). In the treatments of chemical fertilization, the soil OM content only had a quicker increase in the first 8 years, and then fluctuated within a relatively stable range. Fertilization with manure increased the soil OM significantly, as compared to fertilization with chemical fertilizers only. The soil total N content in all fertilization treatments showed a rapid increase in the first 8 years, and the increment was the highest in treatment NPKM. The soil alkaline-hydrolysable N content in all fertilization treatments had a slower increase in the first 12 years, with an average annual increment of 0.66-2.25 mg x kg(-1) x a(-1). In 1994-1998, the soil alkaline-hydrolysable N content in fertilization treatments had a quicker increase, with an average annual increment of 6.45-32.45 mg x kg(-1) x a(-1); but after 1998, the soil alkaline-hydrolysable N content had a slight decrease. It was concluded that organic fertilization was the key measure to stably improve the physical and chemical properties and the productivity of red paddy soils by increasing their

  16. Thermal stability responses of soil organic matter to long-term fertilization practices

    OpenAIRE

    J. Leifeld; Franko, U.; Schulz, E

    2006-01-01

    International audience; We used differential scanning calorimetry (DSC) to infer thermal properties of soil organic matter (SOM) in the static fertilization experiment in Bad Lauchstädt, Germany, which has been established in 1902. Four treatments (null N, change from null to manuring in 1978 NM, change from manuring to null in 1978 MN, and permanent manure and mineral fertilization since 1902 M) were sampled in 2004. Soil organic carbon contents were highest for M (2.4%), lowest for N (1.7%)...

  17. Mechanisms of soil organic carbon accumulation from long-term fertilization strategies in two soils: Evidence from nuclear magnetic resonance spectroscopy analysis

    Science.gov (United States)

    Long-term fertilization strategies have been proven to significantly influence soil organic carbon (SOC) accumulation, while the underlying mechanism remains unclear. Using two long-term (>20 y) field experiments of a double-cropped maize-wheat rotation on a Calcaric Fluvisol and paddy rice on a Hyd...

  18. The long-term fiscal impact of funding cuts to Danish public fertility clinics

    NARCIS (Netherlands)

    Connolly, Mark P.; Postma, Maarten J.; Crespi, Simone; Andersen, Anders Nyboe; Ziebe, Soren

    2011-01-01

    This study evaluated the fiscal impact attributed to recent policy changes that limited funding to public fertility clinics in Denmark. Taking into consideration that introducing patient co-payments will influence the numbers of couples treated, the number of children born every year from assisted r

  19. The long-term fiscal impact of funding cuts to Danish public fertility clinics

    DEFF Research Database (Denmark)

    Connolly, Mark P; Postma, Maarten J; Crespi, Simone

    2011-01-01

    This study evaluated the fiscal impact attributed to recent policy changes that limited funding to public fertility clinics in Denmark. Taking into consideration that introducing patient co-payments will influence the numbers of couples treated, the number of children born every year from assisted...

  20. Long-term Miscanthus Yields Influenced by Location, Genotype, Row Distance, Fertilization and Harvest Season

    DEFF Research Database (Denmark)

    Ugilt Larsen, Søren; Jørgensen, Uffe; Kjeldsen, Jens Bonderup

    2014-01-01

    in Foulum and on coarse sand in Jyndevad. Effects of genotype, row distance and fertilization were investigated. In both trials, yield development over time was characterized by an increase during the first years, optimum yields after 7–8 years and a decrease to a lower level which remained relatively......, and the genotype Giganteus (Miscanthus × giganteus) did not respond to fertilization at all. The highest mean yield in Foulum for the period 1997–2012 was obtained with the shortest row distance (∼18,000 rather than ∼12,000 plants ha−1) and harvested in late autumn, namely 13.1 and 12.0 Mg ha−1 DM annually...... for Giganteus and Goliath, respectively. In Jyndevad, where only Goliath was studied, the highest yield during 1995–2001 was obtained by short row distance, autumn harvest and annual fertilization with 75 kg ha−1 N, with yield increasing up to 116 % in response to fertilization. A mean yield of 14.4 Mg ha−1 DM...

  1. Effect of fertilization on soil phosphorus in a long-term field experiment in southern Finland

    Directory of Open Access Journals (Sweden)

    A. JAAKKOLA

    2008-12-01

    Full Text Available A field experiment was established in 1978 on a loam soil (pH in CaCl 2 7.1 to monitor gradual changes in the soil P status as response to different P fertilization regimes. For 18 years, cereals or grass were cultivated without P fertilization (P 0 or with annual P application of 35 kg ha -1 (P 1 or 70- 79 kg P ha -1 and 71-83 kg K ha -1 (P 2 K. The effects of the treatments on the crop yield varied yearly. The Chang and Jackson fractionation analysis revealed that fertilizer P not taken up by the plant crops was mostly in the NH 4 F extract and to a lesser extent in the NaOH extract. The NH 4 F-extractable P proved also to be the main P source for plants. However, the changes in the reserves of inorganic and organic P did not agree very well with the calculated P balance in soil (applied P minus plant P uptake. This disproportion was partly explained by the soil movement from plots to the neighbouring ones during the experiment. Phosphorus extractable in acid ammonium acetate or water decreased gradually when no P was applied and increased with increasing P accumulation. The changes in the inorganic P reserves due to different P fertilization history were reflected a little more sensitively in the water extraction test than in the acid acetate test.;

  2. The long-term fiscal impact of funding cuts to Danish public fertility clinics

    NARCIS (Netherlands)

    Connolly, Mark P.; Postma, Maarten J.; Crespi, Simone; Andersen, Anders Nyboe; Ziebe, Soren

    2011-01-01

    This study evaluated the fiscal impact attributed to recent policy changes that limited funding to public fertility clinics in Denmark. Taking into consideration that introducing patient co-payments will influence the numbers of couples treated, the number of children born every year from assisted

  3. Long-Term Effect of Fertilizer and Rice Straw on Mineral Composition and Potassium Adsorption in a Reddish Paddy Soil

    Institute of Scientific and Technical Information of China (English)

    LIAO Yu-lin; ZHENG Sheng-xian; NIE Jun; XIE Jian; LU Yan-hong; QIN Xiao-bo

    2013-01-01

    Increasing K+adsorption can be an effective alternative in building an available K pool in soils to optimize crop recovery and minimize losses into the environment. We hypothesized that long-term fertilization might change K+ adsorption because of changes in the chemical and mineralogical properties of a rice (Oryza sativa L.). The aims of this study were (i) to determine clay minerals in paddy soil clay size fractions using X-ray diffraction methods and a numerical diagram-decomposition method;(ii) to measure K+adsorption isotherms before and after H2O2 oxidation of organic matter, and (iii) to investigate whether K+adsorption is correlated with changes in soil chemical and mineral properties. The 30-yr long-term fertilization treatments caused little change in soil organic C (SOC) but a large variation in soil mineral composition. The whole-clay fraction (<5μm) corresponded more to the fertilization treatment than the fine-clay fraction (<1μm) in terms of percentage of illite peak area. The total percentage of vermiculite-chlorite peak area was significantly negatively correlated with the total percentage of illite peak area in the<5μm soil particles (R=-0.946, P<0.0006). Different fertilization treatments gave significantly different results in K+adsorption. The SOC oxidation test showed positive effects of SOC on K+adsorption at lower K+concentration ( 120 mg L-1) and negative effects at higher K+concentration (240 mg L-1). The K+adsorption by soil clay minerals after SOC oxidization accounted for 60-158%of that by unoxidized soils, suggesting a more important role of soil minerals than SOC on K+adsorption. The K+adsorption potential was significantly correlated to the amount of poorly crystallized illite present (R=0.879, P=0.012). The availability of adsorbed K+for plant growth needs further study.

  4. Long term impact of the endocrine disruptor tributyltin on male fertility following a single acute exposure.

    Science.gov (United States)

    Mitra, Sumonto; Srivastava, Ankit; Khandelwal, Shashi

    2017-10-01

    Declining rate of human fertility is a growing concern, where lifestyle and environmental factors play an important role. We recently demonstrated that tributyltin (TBT), an omnipresent endocrine disruptor, affects testicular cells in vitro. In this study, male Wistar rats were gavaged a single dose of 10, 20, and 30 mg/kg TBT-chloride (TBTC) (to mimic accidental exposure in vivo) and sacrificed on day 3 and day 7, respectively. TBT bioavailability was evaluated by estimating total tin content, and essential metal levels were analyzed along with redox molecules (ROS and GSH/GSSG) to understand the effect on physiological conditions. Blood-testicular barrier (BTB) disruption, levels of associated proteins and activity of proteolytic enzymes were evaluated to understand the effect on BTB. Histological analysis of tissue architecture and effect on protein expression of steroidogenic, stress and apoptotic markers were also evaluated. Widespread TBTC pollution can be an eventual threat to male fertility worldwide. © 2017 Wiley Periodicals, Inc.

  5. The long-term fiscal impact of funding cuts to Danish public fertility clinics

    DEFF Research Database (Denmark)

    Connolly, Mark P; Postma, Maarten J; Crespi, Simone

    2011-01-01

    This study evaluated the fiscal impact attributed to recent policy changes that limited funding to public fertility clinics in Denmark. Taking into consideration that introducing patient co-payments will influence the numbers of couples treated, the number of children born every year from assisted......) and lifetime gross tax contributions to derive the discounted net tax contribution from assisted-conception singletons. An investment of €11,078 in a mother aged...

  6. Impact of long-term fertilization practice on soil structure evolution

    DEFF Research Database (Denmark)

    Naveed, Muhammad; Møldrup, Per; Vogel, Hans-Jörg

    2014-01-01

    The study characterized soil structure development and evolution in six plots that were amended with varying amounts of animalmanure (AM) and NPK fertilizer over a period of 106 years in a long-termfertilization experiment in Bad Lauchstädt, Germany. Two intact soil cores (10-cm diameter and 8-cm...... tall) and bulk soil samples were extracted froma depth between 5 and 15-cmfromeach plot. Soil properties including texture, organic carbon, soil–water characteristic, air permeability and diffusivity were measured and analyzed along with X-ray computed tomography (CT) data. Long......-termapplications of AMand NPK had a major impact on soil organic carbon content which increased from 0.015 kg kg−1 (unfertilized plot) to 0.024 kg kg−1 (well fertilized plot, 30 T ha−1 2y−1 AM with NPK). Total porosity linearly followed the organic carbon gradient, increasing from 0.36 to 0.43 m3 m−3. The water holding...... capacity of the soil was considerably increased with the increase of AM and NPK applications. Gas diffusivity and air permeability measurements clearly indicated that the level of soil aeration improved with increasing AMand NPK fertilizer amount. The three-dimensional X-ray CT visualizations revealed...

  7. [Dynamics of microbial biomass P and its affecting factors in a long-term fertilized black soil].

    Science.gov (United States)

    Li, Dongpo; Wu, Zhijie; Chen, Lijun; Zhu, Ping; Ren, Jun; Liang, Chenghua; Peng, Chang; Gao, Hongjun

    2004-10-01

    This paper studied the microbial biomass P in a long-term fertilized black soil. The soil was fertilized by farmyard manure (M2, M4) and chemical fertilizer (NPK), and the dynamics of soil microbial biomass P was monitored during crop growth season. The results showed that the microbial biomass P in different treatments was 8.75-47.68 mg x kg(-1) (M4), 3.02-37.16 mg x kg(-1) (M2), 1.59-10.62 mg x kg(-1) (NPK), and 0.76-6.74 mg x kg(-1) (CK). The microbial biomass P in M4 and M2 was the highest at reproductive growth stage, and that in NPK and CK was the highest at early growth stage. The significant difference of soil microbial biomass P induced by different amounts and types of fertilizer application was not varied with the period and stage of plant growth. In all treatments, no significant correlation was found between the dynamics of soil microbial biomass P and the soil biological, physical and chemical properties in plant growth period. Soil microbial biomass P had a very significant positive correlation with soil biological, physical and chemical properties (expect K), and a significant positive correlation with the N, P and K contents of plants and soil water content.

  8. Community analysis of arbuscular mycorrhizal fungi and bacteria in the maize mycorrhizosphere in a long-term fertilization trial.

    Science.gov (United States)

    Toljander, Jonas F; Santos-González, Juan C; Tehler, Anders; Finlay, Roger D

    2008-08-01

    In this study, we investigated the impact of organic and mineral fertilizers on the community composition of arbuscular mycorrhizal (AM) fungi and bacteria in the mycorrhizosphere of maize in a field experiment established in 1956, in south-east Sweden. Roots and root-associated soil aggregates were sampled four times during the growing season in 2005, in control plots and in plots amended with calcium nitrate, ammonium sulphate, green manure, farmyard manure or sewage sludge. Fungi in roots were identified by cloning and sequencing, and bacteria in soil aggregates were analysed by terminal-restriction fragment length polymorphism, cloning and sequencing. The community composition of AM fungi and bacteria was significantly influenced by the different fertilizers. Changes in microbial community composition were mainly correlated with changes in pH induced by the fertilization regime. However, other factors, including phosphate and soil carbon content, also contributed significantly to these changes. Changes in bacterial community composition and a reduction in bacterial taxon richness throughout the growing season were also manifest. The results of this study highlight the importance and significant effects of the long-term application of different fertilizers on edaphic factors and specific groups of fungi and bacteria playing a key role in arable soils.

  9. Effects of Long-Term Combined Application of Organic and Mineral Fertilizers on Microbial Biomass, Soil Enzyme Activities and Soil Fertility

    Institute of Scientific and Technical Information of China (English)

    LI Juan; ZHAO Bing-qiang; LI Xiu-ying; JIANG Rui-bo; So Hwat Bing

    2008-01-01

    Soil health is important for the sustainable development of terrestrial ecosystem.In this paper,we studied the relationship between soil quality and soil microbial properties such as soil microbial biomass and soil enzyme activities in order to illustrate the function of soil microbial properties as bio-indicators of soil health.In this study,microbial biomass C and N contents(Cmic&Nmic),soil enzyme activities,and soil fertility with different fertilizer regimes were carried out based on a 15-year long-term fertilizer experiment in Drab Fluvo-aquic soil in Changping County,Beijing,China.At this site,7 different treatments were established in 1991.They were in a wheat-maize rotation receiving either no fertilizer(CK),mineral fertilizers(NPK),mineral fertilizers with wheat straw incorporated(NPKW),mineral fertilizers with incremental wheat straw incorporated(NPKW+),mineral fertilizers plus swine manure(NPKM),mineral fertilizers plus incremental swine manure(NPKM+)or mineral fertilizers with maize straw incorporated(NPKS).In different fertilization treatments Cmic changed from 96.49 to 500.12 mg kg-1,and Nmic changed from 35.89 to 101.82 mg kg-1.Compared with CK,the other treatments increased Cmic&Nmic,Cmic/Corg(organic C)ratios,Cmic/Nmic,urease activity,soil organic matter(SOM),soil total nitrogen(STN),and soil total phosphorus(STP).All these properties in treatment with fertilizers input NPKM+ were the highest.Meantime,long-term combined application of mineral fertilizers with organic manure or crop straw could significantly decrease the soil pH in Fluvo-aquic soil(the pH around 8.00 in this experimental soil).Some of soil microbial properties(Cmic/Nmic,urease activity)were positively correlated with soil nutrients.Cmic/Nmic was significantly correlated with SOM and STN contents.The correlation between catalase activity and soil nutrients was not significant.In addition,except of catalase activity,the soil pH in this experiment was negatively correlated with soil

  10. The long-term fiscal impact of funding cuts to Danish public fertility clinics.

    Science.gov (United States)

    Connolly, Mark P; Postma, Maarten J; Crespi, Simone; Andersen, Anders Nyboe; Ziebe, Søren

    2011-12-01

    This study evaluated the fiscal impact attributed to recent policy changes that limited funding to public fertility clinics in Denmark. Taking into consideration that introducing patient co-payments will influence the numbers of couples treated, the number of children born every year from assisted reproductive technology will be affected. To reflect the government perspective, the model assessed the average life course of a cohort of assisted-conception singletons taking into consideration age-specific, per-capita government transfers (e.g. education, health care, family allowances, education, pensions) and lifetime gross tax contributions to derive the discounted net tax contribution from assisted-conception singletons. An investment of €11,078 in a mother aged fiscal consequences of the policy change on the government over many generations. The analytical framework discussed here estimates the net tax revenue of a cohort of assisted-conception children and the discounted net tax revenue that these children pay to the Danish government over their lifetime. The analysis illustrates that the government will save more costs than those directly related to public fertility services because fewer children are likely to be born and consequently to require government services (e.g. education, health care, family allowances). However, over time as the assisted-conception cohort matures and enters the work force. the reduced number of assisted-conception children, attributed to the funding cuts, will negatively impact government accounts due to lost tax revenue. The policy analysis described here suggests that the economic impact of the fertility policy change is dependent on the time frame over which the analysis is considered. In the short term, it is possible to save on assisted reproduction treatment costs; however, taking into consideration the life course of the diminished size of the assisted-conception cohort, this will negatively influence government accounts in

  11. Soil fertility increases with plant species diversity in a long-term biodiversity experiment.

    Science.gov (United States)

    Dybzinski, Ray; Fargione, Joseph E; Zak, Donald R; Fornara, Dario; Tilman, David

    2008-11-01

    Most explanations for the positive effect of plant species diversity on productivity have focused on the efficiency of resource use, implicitly assuming that resource supply is constant. To test this assumption, we grew seedlings of Echinacea purpurea in soil collected beneath 10-year-old, experimental plant communities containing one, two, four, eight, or 16 native grassland species. The results of this greenhouse bioassay challenge the assumption of constant resource supply; we found that bioassay seedlings grown in soil collected from experimental communities containing 16 plant species produced 70% more biomass than seedlings grown in soil collected beneath monocultures. This increase was likely attributable to greater soil N availability, which had increased in higher diversity communities over the 10-year-duration of the experiment. In a distinction akin to the selection/complementarity partition commonly made in studies of diversity and productivity, we further determined whether the additive effects of functional groups or the interactive effects of functional groups explained the increase in fertility with diversity. The increase in bioassay seedling biomass with diversity was largely explained by a concomitant increase in N-fixer, C4 grass, forb, and C3 grass biomass with diversity, suggesting that the additive effects of these four functional groups at higher diversity contributed to enhance N availability and retention. Nevertheless, diversity still explained a significant amount of the residual variation in bioassay seedling biomass after functional group biomass was included in a multiple regression, suggesting that interactions also increased fertility in diverse communities. Our results suggest a mechanism, the fertility effect, by which increased plant species diversity may increase community productivity over time by increasing the supply of nutrients via both greater inputs and greater retention.

  12. Long-term Nutrient Fertilization Increases CO2 Loss in Arctic Tundra

    Science.gov (United States)

    Graham, L. M.; Natali, S.; Rastetter, E. B.; Shaver, G. R.; Risk, D. A.; Loranty, M. M.; Jastrow, J. D.

    2015-12-01

    As anthropogenic climate change warms the Arctic, organic carbon (C) trapped in permafrost is at an increased risk of being released to the atmosphere as carbon dioxide (CO2). At the same time, higher rates of decomposition may increase nutrient availability and enhance plant growth, leading to an uptake of C that may offset respiratory losses. Arctic tundra ecosystems are highly nitrogen (N) limited, and the indirect effects of warming on nutrient availability will be the most likely outcome of increased temperature on plant productivity. This study aims to understand the effects of nutrient addition on arctic CO2 and H2O exchange in a tundra ecosystem at Toolik Lake Field Station, Alaska. The nutrient addition experiment, which began in 2006, is comprised of 7 fertilization treatments: 0.5, 1, 2, 5, and 10 g m-2 of N as NO3- and NH4+ (1:1) with 0.25, 0.5, 1, 2.5, and 5 g m-2 of phosphorus as PO43-; 5 g m-2 of N as NO3-; 5 g m-2 of N as NH4+, and one control plot. Plot-level CO2 and H2O exchange was measured at 5 light levels 7 times over a four-week period in June and July 2015. We measured ecosystem CO2 and H2O exchange using a rectangular plexiglass chamber (0.49 m2) that was connected to an infrared gas analyzer (LI-840). Other ecosystem variables measured include thaw depth, soil moisture and temperature, and normalized difference vegetation index. After 10 years of nutrient addition, fertilization significantly altered ecosystem C cycling. Soil respiration was greatest in the highest fertilization treatment (2.97 μmol m-2 s-1), increasing linearly with nutrient level at a rate of 0.133 μmol m-2 s-1 per g m-2 of N added (R2=0.914). Net CO2 uptake was greatest under highest fertilization (-2.06 μmol m-2 s-1), decreasing linearly with nutrient addition at a rate of -0.068 μmol m-2 s-1 per g m-2 of N added (R2=0.687). These results suggest that as nutrients become more available under a warmer climate, plant productivity increases may not offset respiratory

  13. Thermal stability of soil organic matter responds to long-term fertilization practices

    Directory of Open Access Journals (Sweden)

    J. Leifeld

    2006-04-01

    Full Text Available We used differential scanning calorimetry (DSC to infer thermal properties of soil organic matter (SOM in the static fertilization experiment in Bad Lauchstädt, Germany, which has been established in 1902. Four treatments (null N, change from null to manuring in 1978 NM, change from manuring to null in 1978 MN, and permanent manure and mineral fertilization since 1902 M were sampled in 2004. Soil organic carbon contents were highest for M (2.4%, lowest for N (1.7%, and similar for MN and NM (2.2%. DSC thermograms were characterized by three peaks at around 354, 430, and 520°C, which were assigned to as thermally labile and stable SOM and combustion residues from lignite, respectively. DSC peak temperatures were relatively constant among treatments, but peak heights normalized to the organic C content of the soil were significantly different for labile and stable SOM. Labile C was higher for M>MN=NM=N, and stable C decreased in the order N=NM>MN=M, showing that agricultural depletion of SOM increases the share of thermally stable C. Lignite-derived C was not affected by management, suggesting a homogeneous deposition across treatments.

  14. Thermal stability responses of soil organic matter to long-term fertilization practices

    Directory of Open Access Journals (Sweden)

    J. Leifeld

    2006-01-01

    Full Text Available We used differential scanning calorimetry (DSC to infer thermal properties of soil organic matter (SOM in the static fertilization experiment in Bad Lauchstädt, Germany, which has been established in 1902. Four treatments (null N, change from null to manuring in 1978 NM, change from manuring to null in 1978 MN, and permanent manure and mineral fertilization since 1902 M were sampled in 2004. Soil organic carbon contents were highest for M (2.4%, lowest for N (1.7%, and similar for MN and NM (2.2%. Three heat flow peaks at around 354°C, 430°C, and 520°C, which were assigned to as thermally labile and stable SOM and combustion residues from lignite, respectively, characterized DSC thermograms. DSC peak temperatures were relatively constant among treatments, but peak heights normalized to the organic C content of the soil were significantly different for labile and stable SOM. Labile C was higher for M>MN=NM=N, and stable C decreased in the order N=NM>MN=M, showing that agricultural depletion of SOM increases the share of thermally stable C. Lignite-derived C was not affected by management, suggesting a homogeneous deposition across treatments.

  15. Long-term nutrient fertilization and the carbon balance of permanent grassland: any evidence for sustainable intensification?

    Science.gov (United States)

    Fornara, Dario A.; Wasson, Elizabeth-Anne; Christie, Peter; Watson, Catherine J.

    2016-09-01

    Sustainable grassland intensification aims to increase plant yields while maintaining the ability of soil to act as a sink rather than sources of atmospheric CO2. High biomass yields from managed grasslands, however, can be only maintained through long-term nutrient fertilization, which can significantly affect soil carbon (C) storage and cycling. Key questions remain about (1) how long-term inorganic vs. organic fertilization influences soil C stocks, and (2) how soil C gains (or losses) contribute to the long-term C balance of managed grasslands. Using 43 years of data from a permanent grassland experiment, we show that soils not only act as significant C sinks but have not yet reached C saturation. Even unfertilized control soils showed C sequestration rates of 0.35 Mg C ha-1 yr-1 (i.e. 35 g C m-2 yr-1; 0-15 cm depth) between 1970 and 2013. High application rates of liquid manure (i.e. cattle slurry) further increased soil C sequestration to 0.86 Mg C ha-1 yr-1 (i.e. 86 g C m-2 yr-1) and a key cause of this C accrual was greater C inputs from cattle slurry. However, average coefficients of slurry-C retention in soils suggest that 85 % of C added yearly through liquid manure is lost possibly via CO2 fluxes and organic C leaching. Inorganically fertilized soils (i.e. NPK) had the lowest C-gain efficiency (i.e. unit of C gained per unit of N added) and lowest C sequestration (similar to control soils). Soils receiving cattle slurry showed higher C-gain and N-retention efficiencies compared to soils receiving NPK or pig slurry. We estimate that net rates of CO2-sequestration in the top 15 cm of the soil can offset 9-25 % of GHG (greenhouse gas) emissions from intensive management. However, because of multiple GHG sources associated with livestock farming, the net C balance of these grasslands remains positive (9-12 Mg CO2-equivalent ha-1 yr-1), thus contributing to climate change. Further C-gain efficiencies (e.g. reduced enteric fermentation and use of feed

  16. The long-term prognosis for live birth in couples initiating fertility treatments

    DEFF Research Database (Denmark)

    Malchau, S S; Henningsen, A A; Loft, A

    2017-01-01

    , across clinics, evaluating live births after insemination, ART and natural conceptions. STUDY DESIGN, SIZE, DURATION: This register-based national cohort study from Denmark includes all women initiating fertility treatments in public and private clinics with homologous gametes in 2007-2010. PARTICIPANTS...... were estimated 2, 3 and 5 years from the first treatment cycle, in all women, including drop-outs. Birthrates were stratified by type of first treatment (ART/IUI), mode of conception (ART/IUI/natural conception) and female age. MAIN RESULTS AND THE ROLE OF CHANCE: Within 5 years, in women aged ... years (N = 3553), 35-39 years (N = 1156) and ≥40 years (N = 451), a total of 64%, 49% and 16% had a live birth due to treatment, respectively. Additionally, in women aged conception, yielding total 5-year birthrates of 80...

  17. Soil phosphorus dynamic, balance and critical P values in long-term fertilization experiment in Taihu Lake region, China

    Institute of Scientific and Technical Information of China (English)

    SHI Lin-lin; SHEN Ming-xing; LU Chang-yin; WANG Hai-hou; ZHOU Xin-wei; JIN Mei-juan; WU Tong-dong

    2015-01-01

    Phosphorus (P) is an important macronutrient for plant but can also cause potential environmental risk. In this paper, we studied the long-term fertilizer experiment (started 1980) to assess the soil P dynamic, balance, critical P value and the crop yield response in Taihu Lake region, China. To avoid the effect of nitrogen (N) and potassium (K), only the folowing treatments were chosen for subsequent discussion, including: C0 (control treatment without any fertilizer or organic manure), CNK treatment (mineral N and K only), CNPK (balanced fertilization with mineral N, P and K), MNK (integrated organic ma-nure and mineral N and K), and MNPK (organic manure plus balanced fertilization). The results revealed that the response of wheat yield was more sensitive than rice, and no signiifcant differences of crop yield had been detected among MNK, CNPK and MNPK until 2013. Dynamic and balance of soil total P (TP) and Olsen-P showed soil TP pool was enlarged signiifcantly over consistent fertilization. However, the diminishing marginal utility of soil Olsen-P was also found, indicating that high-level P application in the present condition could not increase soil Olsen-P contents anymore. Linear-linear and Mitscherlich models were used to estimate the critical value of Olsen-P for crops. The average critical P value for rice and wheat was 3.40 and 4.08 mg kg–1, respectively. The smaler critical P value than in uplands indicated a stronger ability of P supply for crops in this paddy soil. We concluded that no more mineral P should be applied in rice-wheat system in Taihu Lake region if soil Olsen-P is higher than the critical P value. The agricultural technique and management referring to acti-vate the plant-available P pool are also considerable, such as integrated use of low-P organic manure with mineral N and K.

  18. Long-term effects of fertilizer on soil enzymatic activity of wheat field soil in Loess Plateau, China.

    Science.gov (United States)

    Hu, Weigang; Jiao, Zhifang; Wu, Fasi; Liu, Yongjun; Dong, Maoxing; Ma, Xiaojun; Fan, Tinglu; An, Lizhe; Feng, Huyuan

    2014-12-01

    The effects of long-term (29 years) fertilization on local agro-ecosystems in the Loess Plateau of northwest China, containing a single or combinations of inorganic (Nitrogen, N; Phosphate, P) and organic (Mature, M Straw, S) fertilizer, including N, NP, SNP, M, MNP, and a control. The soil enzymes, including dehydrogenase, urease, alkaline phosphatase, invertase and glomalin, were investigated in three physiological stages (Jointing, Dough, and Maturity) of wheat growth at three depths of the soil profile (0-15, 16-30, 31-45 cm). We found that the application of farmyard manure and straw produced the highest values of soil enzymatic activity, especially a balanced applied treatment of MNP. Enzymatic activity was lowest in the control. Values were generally highest at dough, followed by the jointing and maturity stages, and declined with soil profile depth. The activities of the enzymes investigated here are significantly correlated with each other and are correlated with soil nutrients, in particular with soil organic carbon. Our results suggest that a balanced application of fertilizer nutrients and organic manure (especially those containing P) has positive effects on multiple soil chemical parameters, which in turn enhances enzyme activity. We emphasize the role of organic manure in maintaining soil organic matter and promoting biological activity, as its application can result in a substantial increase in agricultural production and can be sustainable for many years.

  19. Effects of long-term differential fertilization on eukaryotic microbial communities in an arable soil: a multiple barcoding approach.

    Science.gov (United States)

    Lentendu, Guillaume; Wubet, Tesfaye; Chatzinotas, Antonis; Wilhelm, Christian; Buscot, François; Schlegel, Martin

    2014-07-01

    To understand the fine-scale effects of changes in nutrient availability on eukaryotic soil microorganisms communities, a multiple barcoding approach was used to analyse soil samples from four different treatments in a long-term fertilization experiment. We performed PCR amplification on soil DNA with primer pairs specifically targeting the 18S rRNA genes of all eukaryotes and three protist groups (Cercozoa, Chrysophyceae-Synurophyceae and Kinetoplastida) as well as the ITS gene of fungi and the 23S plastid rRNA gene of photoautotrophic microorganisms. Amplicons were pyrosequenced, and a total of 88,706 quality filtered reads were clustered into 1232 operational taxonomic units (OTU) across the six data sets. Comparisons of the taxonomic coverage achieved based on overlapping assignment of OTUs revealed that half of the eukaryotic taxa identified were missed by the universal eukaryotic barcoding marker. There were only little differences in OTU richness observed between organic- (farmyard manure), mineral- and nonfertilized soils. However, the community compositions appeared to be strongly structured by organic fertilization in all data sets other than that generated using the universal eukaryotic 18S rRNA gene primers, whereas mineral fertilization had only a minor effect. In addition, a co-occurrence based network analysis revealed complex potential interaction patterns between OTUs from different trophic levels, for example between fungivorous flagellates and fungi. Our results demonstrate that changes in pH, moisture and organic nutrients availability caused shifts in the composition of eukaryotic microbial communities at multiple trophic levels.

  20. The long-term effects of superovulation on fertility and sexual behavior of male offspring in mice.

    Science.gov (United States)

    Wei, Zeng-Tao; Lu, Xi-Lan; Zhang, Gang; Yu, Jing; Li, Hua; Jia, Gui-Hua; Li, Jun-Tao; Zhang, Jian-Min

    2014-05-01

    To evaluate the long-term effects of superovulation on fertility and sexual behavior of male offspring in mice. The mice were superovaluted, and the fertility of male offspring (F1 generation and F2 generation) were evaluated in terms of the percentage of plugs and pregnancies, serum testosterone concentrations, and sperm motility. Furthermore, the sexual behavior of male offspring and sex ratio (F1 generation and F2 generation) were measured. There were no significant differences in the percentage of plug and pregnancies, serum testosterone concentrations, sperm motilities and sex ratio between the offspring in naturally conceived group and superovulation groups (both F1 generation and F2 generation). The sperm hyperactivity at 90 min after incubation of F1 generation in naturally conceived group were higher than that of F1 generation in superovulation group, but the differences did not reach statistical significance. The offspring produced by superovaluted oocytes (both F1 generation and F2 generation) did not exhibit significant alterations in sexual behavior. No significant alterations were found in fertility and sexual behavior of male offspring in mice produced by superovaluted oocytes compared with those of naturally conceived offspring.

  1. Long-term changes in the chemical composition of soil organic matter, depending on fertilization and crop rotation

    Science.gov (United States)

    Tammik, Kerttu; Kauer, Karin; Astover, Alar

    2017-04-01

    The objective of this study was to determine whether it is possible to assess the impact of different management practices (crop rotation, fertilization (organic and mineral fertilizers) on the chemical composition of soil organic matter, using Fourier transform infrared spectroscopy (FTIR). The study is based IOSDV long-term (established in 1989) three field crop rotation (potato-wheat-barely) experiment located in Tartu, Estonia. Soil samples (Stagnic Albeluvisol) were collected from the 0-20 cm depth in the autumn of 2015, air dried, sieved to 2 mm and grinded to obtain homogeneous samples. The content of soil organic matter was measured by the dry combustion method in a varioMax CNS elemental analyser (ELEMENTAR, Germany). The samples were analysed using Thermo-Nicolet iS10 Fourier Transform Infrared Spectrophotometer (FT-IR) and OMNIC software. An intense and sharp peak was recorded in the region of Si-O vibrations of clay minerals and polysaccharides in all samples analysed. The volume of the peak correlated with the quantity of fertilizers administered

  2. Plant and soil fungal but not soil bacterial communities are linked in long-term fertilized grassland

    Science.gov (United States)

    Cassman, Noriko A.; Leite, Marcio F. A.; Pan, Yao; de Hollander, Mattias; van Veen, Johannes A.; Kuramae, Eiko E.

    2016-03-01

    Inorganic fertilization and mowing alter soil factors with subsequent effects-direct and indirect - on above- and below-ground communities. We explored direct and indirect effects of long-term fertilization (N, P, NPK, Liming) and twice yearly mowing on the plant, bacterial and fungal communities and soil factors. We analyzed co-variation using 16S and 18S rRNA genes surveys, and plant frequency and edaphic factors across treatments. The plant and fungal communities were distinct in the NPK and L treatments, while the bacterial communities and soil factors were distinct in the N and L treatments. Plant community diversity and evenness had low diversity in the NPK and high diversity in the liming treatment, while the diversity and evenness of the bacterial and fungal communities did not differ across treatments, except of higher diversity and evenness in the liming treatment for the bacteria. We found significant co-structures between communities based on plant and fungal comparisons but not between plant and bacterial nor bacterial and fungal comparisons. Our results suggested that the plant and fungal communities are more tightly linked than either community with the bacterial community in fertilized soils. We found co-varying plant, bacterial and fungal taxa in different treatments that may indicate ecological interactions.

  3. Trends of Yield and Soil Fertility in a Long-Term Wheat-Maize System

    Institute of Scientific and Technical Information of China (English)

    YANG Xue-yun; SUN Ben-hua; ZHANG Shu-lan

    2014-01-01

    The sustainability of the wheat-maize rotation is important to China’s food security. Intensive cropping without recycling crop residues or other organic inputs results in the loss of soil organic matter (SOM) and nutrients, and is assumed to be non-sustainable. We evaluated the effects of nine different treatments on yields, nitrogen use efifciency, P and K balances, and soil fertility in a wheat-maize rotation system (1991-2010) on silt clay loam in Shaanxi, China. The treatments involved the application ofrecommended dose of nitrogen (N), nitrogen and phosphorus (NP), nitrogen and potassium (NK), phosphorus and potassium (PK), combined NPK, wheat or maize straw (S) with NPK (SNPK), or dairy manure (M) with NPK (M1NPK and M2NPK), along with an un-treated control treatment (CK). The mean yields of wheat and maize ranged from 992 and 2 235 kg ha-1 under CK to 5962 and 6894 kg ha-1 under M2NPK treatment, respectively. Treatments in which either N or P was omitted (N, NK and PK) gave signiifcantly lower crop yields than those in which both were applied. The crop yields obtained under NP, NPK and SNPK treatments were statistically identical, as were those obtained under SNPK and MNPK. However, M2NPK gave a signiifcant higher wheat yield than NP, and MNPK gave signiifcant higher maize yield than both NP and NPK. Wheat yields increased signiifcantly (by 86 to 155 kg ha-1 yr-1) in treatments where NP was applied, but maize yields did not. In general, the nitrogen use efifciency of wheat was the highest under the NP and NPK treatments; for maize, it was the highest under MNPK treatment. The P balance was highly positive under MNPK treatment, increasing by 136 to 213 kg ha-1 annually. While the K balance was negative in most treatments, ranging from 31 to 217 kg ha-1 yr-1, levels of soil available K remained unchanged or increased over the 20 yr. SOM levels increased signiifcantly in all treatments. Overall, the results indicated that combinations of organic manure and

  4. Estimation of PCB content in agricultural soils associated with long-term fertilization with organic waste.

    Science.gov (United States)

    Antolín-Rodríguez, Juan M; Sánchez-Báscones, Mercedes; Martín-Ramos, Pablo; Bravo-Sánchez, Carmen T; Martín-Gil, Jesús

    2016-06-01

    Polychlorinated biphenyl (PCB) pollution related to the use of organic waste as fertilizers in agricultural soils is a cause of major concern. In the study presented herein, PCB concentration was studied through a field trial conducted in two agricultural soils in the province of Palencia (Spain) over a 4-year period, assessing the impact of irrigation and of different types of organic waste materials. The amounts of organic waste added to the soil were calculated according to the nitrogen needs of the crop, and the concentration of PCBs was determined before and after the application of the organic waste. The resulting persistence of the total PCB content in the agricultural soils, compared with the PCB concentration in the original soils, ranged from 27% to 90%, with the lowest value corresponding to irrigated soils treated with municipal solid waste compost (MSWC) and the highest value to non-irrigated soils treated with composted sewage sludge (CSS). An estimate of the PCB content in agricultural soils after the application of organic waste materials until year 2050 was obtained, resulting in a value below 5 ng·g(-1), considered a background value for soils in sites far away from potential pollution sources.

  5. [Characteristics of soil organic carbon mineralization at different temperatures in paddy soils under long-term fertilization].

    Science.gov (United States)

    Lin, Shan; Chen, Tao; Zhao, Jin-Song; Xiang, Rong-Biao; Hu, Rong-Gui; Zhang, Shui-Qing; Wang, Mi-Lan; Lu, Zhao-Qi

    2014-05-01

    Dynamics of soil organic carbon mineralization affected by long-term fertilizations and temperature in relation to different soil carbon fractions were investigated in paddy soils. Soil samples were collected from the plough layer of 3 long-term national experimental sites in Xinhua, Ningxiang and Taojiang counties of Hunan Province. Mineralization of soil organic C was estimated by 33-day aerobic incubation at different temperatures of 10, 20 and 30 degrees C. The results showed that the rates of CO2 production were higher during the earlier phase (0-13 d) in all treatments, and then decreased according to a logarithm function. Higher incubation temperature strengthened C mineralization in the different treatments. The quantities of cumulative CO2 production in NPK with manure or straw treatments were greater than in inorganic fertilizers treatments. The Q10 values in the different soil treatments ranged from 1.01-1.53. There were significantly positive correlations between the Q10 values and soil total organic carbon (TOC), easy oxidation organic carbon (EOOC), humic acid carbon (C(HA)), fulvic acid carbon (CFA). The cumulative amount of mineralized C was significantly positively correlated with microbial biomass carbon (MBC) at 10 and 20 degrees C, but not significantly at 30 degrees C. Significant correlations were found between the cumulative amount of mineralized C and different soil carbon fractions and C(HA)/C(FA). The correlations of differ- ent soil carbon fractions with the ratio of cumulative mineralized C to TOC were negatively correlated at 10 degrees C, but not significantly at 20 and 30 degrees C. These results suggested that the application of NPK with manure or straw would be helpful to increase the sequestration of C in paddy soils and reduce its contribution of CO2 release in the atmosphere.

  6. [Effects of long-term fertilization on microbial biomass carbon and nitrogen and on carbon source utilization of microbes in a red soil].

    Science.gov (United States)

    Sun, Feng-xia; Zhang, Wei-hua; Xu, Ming-gang; Zhang, Wen-ju; Li, Zhao-qiang; Zhang, Jing-ye

    2010-11-01

    In order to explore the effects of long-term fertilization on the microbiological characters of red soil, soil samples were collected from a 19-year long-term experimental field in Qiyang of Hunan, with their microbial biomass carbon (MBC) and nitrogen (MBN) and microbial utilization ratio of carbon sources analyzed. The results showed that after 19-year fertilization, the soil MBC and MBN under the application of organic manure and of organic manure plus inorganic fertilizers were 231 and 81 mg x kg(-1) soil, and 148 and 73 mg x kg(-1) soil, respectively, being significantly higher than those under non-fertilization, inorganic fertilization, and inorganic fertilization plus straw incorporation. The ratio of soil MBN to total N under the application of organic manure and of organic manure plus inorganic fertilizers was averagely 6.0%, significantly higher than that under non-fertilization and inorganic fertilization. Biolog-ECO analysis showed that the average well color development (AWCD) value was in the order of applying organic manure plus inorganic fertilizers = applying organic manure > non-fertilization > inorganic fertilization = inorganic fertilization plus straw incorporation. Under the application of organic manure or of organic manure plus inorganic fertilizers, the microbial utilization rate of carbon sources, including carbohydrates, carboxylic acids, amino acids, polymers, phenols, and amines increased; while under inorganic fertilization plus straw incorporation, the utilization rate of polymers was the highest, and that of carbohydrates was the lowest. Our results suggested that long-term application of organic manure could increase the red soil MBC, MBN, and microbial utilization rate of carbon sources, improve soil fertility, and maintain a better crop productivity.

  7. [Effects of long-term fertilization on soil organic carbon pool and carbon sequestration under double rice cropping].

    Science.gov (United States)

    Sun, Yu-Tao; Liao, Yu-Lin; Zheng, Sheng-Xian; Nie, Jun; Lu, Yan-Hong; Xie, Jian

    2013-03-01

    This paper studied the effects of 30 years (1981-2010) fertilization with chemical N, P, and K, pig manure (PM), and rice straw (RS) on the soil organic carbon (SOC) and its components contents under intensive double rice cropping. The experiment was established on a typic Hapli-Stagnic Anthrosols in Hunan in 1981, and the soil samples were collected in November 2010. In treatment NPK, the contents of SOC, particulate organic C (POC), and KMnO4-oxidizable C (KMnO4-C) were higher than those in treatments NP and NK. The combined application of chemical and organic fertilizers (treatments NK+PM, NP+RS, and NPK+RS) made the contents of SOC, POC, and KMnO4-C have a significant increase, as compared with chemical fertilizations. Treatment NK+PM had the highest contents of SOC (84.71 t C.hm-2), POC (8.94 t C.hm-2), and KMnO4-C (21.09 t C.hm-2) in top soil (0-45 cm), followed by treatment NPK+RS. Treatment NK+PM had the highest C sequestration (485 kg C.hm-2.a-1) , followed by treatment NPK+RS (375 kg C.hm-2.a-1). The C sequestration efficiency (CSE) of SOC in the treatments of chemical fertilizers plus pig manure or rice straw was obviously higher than that in the treatments of chemical fertilizations, and the CSE of the POC in fertilization treatments (ranging from 0.4% and 1.2%) was lower than that of the KMnO4-C (ranging from 3.0% to 8.3%). By using the values of humification constant (h) and the decay constant (k) in Jenkinson' s equation, it was possible to predict the SOC storages in different treatments in the year 2010; and by using Jenkinson' s equation, it was possible to calculate the C input required to maintain the SOC storages in the year 1981 (AE). The increase of the SOC in treatments NK+PM, NP+RS, and NPK+RS was due to the annual C input being higher than the AE. It was considered that in the double rice cropping areas in subtropical region of China, long-term application of chemical fertilizers combined with pig manure or rice straw could promote the

  8. Long-Term Application of Bioorganic Fertilizers Improved Soil Biochemical Properties and Microbial Communities of an Apple Orchard Soil.

    Science.gov (United States)

    Wang, Lei; Yang, Fang; E, Yaoyao; Yuan, Jun; Raza, Waseem; Huang, Qiwei; Shen, Qirong

    2016-01-01

    Soil biochemical properties and microbial communities are usually considered as important indicators of soil health because of their association with plant nutrition. In this study, we investigated the impact of long-term application of bioorganic fertilizer (BOF) on soil biochemical properties and microbial communities in the apple orchard soil of the Loess Plateau. The experiment included three treatments: (1) control without fertilization (CK); (2) chemical fertilizer application (CF); and (3) bioorganic fertilizer application (BOF). The high throughput sequencing was used to examine the bacterial and fungal communities in apple orchard soil. The results showed that the BOF treatment significantly increased the apple yield during the experimental time (2009-2015). The application of BOF significantly increased the activities of catalase and invertase compared to those in CK and CF treatments. The high throughput sequencing data showed that the application of BOF changed the microbial community composition of all soil depths considered (0-20 cm, 20-40 cm, and 40-60 cm), e.g., the relative abundance of bio-control bacteria (Xanthomonadales, Lysobacter, Pseudomonas, and Bacillus), Proteobacteria, Bacteroidetes, Ohtaekwangia, Ilyonectria, and Lecanicillium was increased while that of Acidobacteria, Chloroflexi, Gp4, Gp6 and Sphaerobacter was decreased. The increase in apple yield after the application of BOF might be due to increase in organic matter, total nitrogen and catalase and invertase activities of soil and change in the bacterial community composition by enriching Bacillus, Pseudomonas, Lysobacter, and Ohtaekwangia. These results further enhance the understanding on how BOFs alter soil microbial community composition to stimulate soil productivity.

  9. Long-Term Application of Bioorganic Fertilizers Improved Soil Biochemical Properties and Microbial Communities of an Apple Orchard Soil

    Science.gov (United States)

    Wang, Lei; Yang, Fang; E, Yaoyao; Yuan, Jun; Raza, Waseem; Huang, Qiwei; Shen, Qirong

    2016-01-01

    Soil biochemical properties and microbial communities are usually considered as important indicators of soil health because of their association with plant nutrition. In this study, we investigated the impact of long-term application of bioorganic fertilizer (BOF) on soil biochemical properties and microbial communities in the apple orchard soil of the Loess Plateau. The experiment included three treatments: (1) control without fertilization (CK); (2) chemical fertilizer application (CF); and (3) bioorganic fertilizer application (BOF). The high throughput sequencing was used to examine the bacterial and fungal communities in apple orchard soil. The results showed that the BOF treatment significantly increased the apple yield during the experimental time (2009–2015). The application of BOF significantly increased the activities of catalase and invertase compared to those in CK and CF treatments. The high throughput sequencing data showed that the application of BOF changed the microbial community composition of all soil depths considered (0–20 cm, 20–40 cm, and 40–60 cm), e.g., the relative abundance of bio-control bacteria (Xanthomonadales, Lysobacter, Pseudomonas, and Bacillus), Proteobacteria, Bacteroidetes, Ohtaekwangia, Ilyonectria, and Lecanicillium was increased while that of Acidobacteria, Chloroflexi, Gp4, Gp6 and Sphaerobacter was decreased. The increase in apple yield after the application of BOF might be due to increase in organic matter, total nitrogen and catalase and invertase activities of soil and change in the bacterial community composition by enriching Bacillus, Pseudomonas, Lysobacter, and Ohtaekwangia. These results further enhance the understanding on how BOFs alter soil microbial community composition to stimulate soil productivity. PMID:27965631

  10. Long-term application of bioorganic fertilizers improved soil biochemical properties and microbial communities of an apple orchard soil

    Directory of Open Access Journals (Sweden)

    Wang Lei

    2016-11-01

    Full Text Available Soil biochemical properties and microbial communities are usually considered as important indicators of soil health because of their association with plant nutrition. In this study, we investigated the impact of long-term application of bioorganic fertilizer (BOF on soil biochemical properties and microbial communities in the apple orchard soil of the Loess Plateau. The experiment included three treatments: (1 control without fertilization (CK; (2 chemical fertilizer application (CF; and (3 bioorganic fertilizer application (BOF. The high throughput sequencing was used to examine the bacterial and fungal communities in apple orchard soil. The results showed that the BOF treatment significantly increased the apple yield during the experimental time (2009-2015. The application of BOF significantly increased the activities of catalase and invertase compared to those in CK and CF treatments. The high throughput sequencing data showed that the application of BOF changed the microbial community composition of all soil depths considered (0-20cm, 20-40cm, and 40-60cm, e.g., the relative abundance of bio-control bacteria (Xanthomonadales, Lysobacter, Pseudomonas and Bacillus, Proteobacteria, Bacteroidetes, Ohtaekwangia, Ilyonectria and Lecanicillium was increased while that of Acidobacteria, Chloroflexi, Gp4, Gp6 and Sphaerobacter was decreased. The increase in apple yield after the application of BOF might be due to increase in organic matter, total nitrogen and catalase and invertase activities of soil and change in the bacterial community composition by enriching Bacillus, Pseudomonas, Lysobacter and Ohtaekwangia. These results further enhance the understanding on how BOFs alter soil microbial community composition to stimulate soil productivity.

  11. Climate Change and Potassium Effects Under Different N-Fertilization Input on Potato (Solanum tuberosum L.) Yield in a Long Term Field Experiment

    Science.gov (United States)

    László, Márton, ,, Dr.

    2010-05-01

    -106. László, M.-Silva, J.B.C.-José, A.B. 2000b. Ecological friendly dragée technics on different crops and vegetables seeds. Acta Agronomica Óváriensis. 42: 107-111. László, M.-Silva, J.B.C.-Jose, A.B. 2000c. Ecological friendly dragée technics to sustainable precision agriculture. Fertilization in the Third Millenium. CASISCF. Beijing Márton, L. 2000a. Effects of NPK fertilizers on potato (Solanum tuberosum L.) yield. Doctoral Ph.D Dissertation. University of Veszprém, Keszthely. Márton, L. 2000b. Effects of NPK fertilizers on potato (Solanum tuberosum L.) yield. Doctoral Ph.D Thesis. University of Veszprém, Keszthely. Márton L. 2001a. Climate change and N, P, K, Mg fertilization effect analysis at Tisza- river basin in a long term field experiment. Szent István University, Gödöllő, 21. p. Márton, L. 2001b. Climete change effets on rye (Secale cereale L.) yield. Agrochemistry and Soil Science. Budapest. In press. Márton, L. 2001c. Climate change and fertilization effect analysis at the Tisza- river basin on rye yield. SZINET. University of Szent István. Gödöllő. Márton, L.-Kádár, I.-Estáquio M.J. 2000. Effects of Crotalaria juncea L. and Crotalaria spectabilis ROTH on soil fertility and soil conservation. ESSC. Man and Soil at the Third Millennium. Abstract Book. 195. Valencia ACKNOWLEDGEMENT This study were supported by Research Institute for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences (RISSAC-HAS) Address of author: László M., Research Institute for Soil Science and Agricultural Chemistry of the Hungarian Academy of Sciences, H-1022 Budapest, II. Herman O. u. 15., E-mail:marton@gw.rissac.hu

  12. Significant alteration of soil bacterial communities and organic carbon decomposition by different long-term fertilization management conditions of extremely low-productivity arable soil in South China.

    Science.gov (United States)

    Xun, Weibing; Zhao, Jun; Xue, Chao; Zhang, Guishan; Ran, Wei; Wang, Boren; Shen, Qirong; Zhang, Ruifu

    2016-06-01

    Different fertilization managements of red soil, a kind of Ferralic Cambisol, strongly affected the soil properties and associated microbial communities. The association of the soil microbial community and functionality with long-term fertilization management in the unique low-productivity red soil ecosystem is important for both soil microbial ecology and agricultural production. Here, 454 pyrosequencing analysis of 16S recombinant ribonucleic acid genes and GeoChip4-NimbleGen-based functional gene analysis were used to study the soil bacterial community composition and functional genes involved in soil organic carbon degradation. Long-term nitrogen-containing chemical fertilization-induced soil acidification and fertility decline and significantly altered the soil bacterial community, whereas long-term organic fertilization and fallow management improved the soil quality and maintained the bacterial diversity. Short-term quicklime remediation of the acidified soils did not change the bacterial communities. Organic fertilization and fallow management supported eutrophic ecosystems, in which copiotrophic taxa increased in relative abundance and have a higher intensity of labile-C-degrading genes. However, long-term nitrogen-containing chemical fertilization treatments supported oligotrophic ecosystems, in which oligotrophic taxa increased in relative abundance and have a higher intensity of recalcitrant-C-degrading genes but a lower intensity of labile-C-degrading genes. Quicklime application increased the relative abundance of copiotrophic taxa and crop production, although these effects were utterly inadequate. This study provides insights into the interaction of soil bacterial communities, soil functionality and long-term fertilization management in the red soil ecosystem; these insights are important for improving the fertility of unique low-productivity red soil.

  13. Community structure of ammonia-oxidizing bacteria under long-term application of mineral fertilizer and organic manure in a sandy loam soil.

    Science.gov (United States)

    Chu, Haiyan; Fujii, Takeshi; Morimoto, Sho; Lin, Xiangui; Yagi, Kazuyuki; Hu, Junli; Zhang, Jiabao

    2007-01-01

    The effects of mineral fertilizer (NPK) and organic manure on the community structure of soil ammonia-oxidizing bacteria (AOB) was investigated in a long-term (16-year) fertilizer experiment. The experiment included seven treatments: organic manure, half organic manure N plus half fertilizer N, fertilizer NPK, fertilizer NP, fertilizer NK, fertilizer PK, and the control (without fertilization). N fertilization greatly increased soil nitrification potential, and mineral N fertilizer had a greater impact than organic manure, while N deficiency treatment (PK) had no significant effect. AOB community structure was analyzed by PCR-denaturing gradient gel electrophoresis (PCR-DGGE) of the amoA gene, which encodes the alpha subunit of ammonia monooxygenase. DGGE profiles showed that the AOB community was more diverse in N-fertilized treatments than in the PK-fertilized treatment or the control, while one dominant band observed in the control could not be detected in any of the fertilized treatments. Phylogenetic analysis showed that the DGGE bands derived from N-fertilized treatments belonged to Nitrosospira cluster 3, indicating that N fertilization resulted in the dominance of Nitrosospira cluster 3 in soil. These results demonstrate that long-term application of N fertilizers could result in increased soil nitrification potential and the AOB community shifts in soil. Our results also showed the different effects of mineral fertilizer N versus organic manure N; the effects of P and K on the soil AOB community; and the importance of balanced fertilization with N, P, and K in promoting nitrification functions in arable soils.

  14. Water consumption characteristics and water use efficiency of winter wheat under long-term nitrogen fertilization regimes in northwest China.

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    Yangquanwei Zhong

    Full Text Available Water shortage and nitrogen (N deficiency are the key factors limiting agricultural production in arid and semi-arid regions, and increasing agricultural productivity under rain-fed conditions often requires N management strategies. A field experiment on winter wheat (Triticum aestivum L. was begun in 2004 to investigate effects of long-term N fertilization in the traditional pattern used for wheat in China. Using data collected over three consecutive years, commencing five years after the experiment began, the effects of N fertilization on wheat yield, evapotranspiration (ET and water use efficiency (WUE, i.e. the ratio of grain yield to total ET in the crop growing season were examined. In 2010, 2011 and 2012, N increased the yield of wheat cultivar Zhengmai No. 9023 by up to 61.1, 117.9 and 34.7%, respectively, and correspondingly in cultivar Changhan No. 58 by 58.4, 100.8 and 51.7%. N-applied treatments increased water consumption in different layers of 0-200 cm of soil and thus ET was significantly higher in N-applied than in non-N treatments. WUE was in the range of 1.0-2.09 kg/m3 for 2010, 2011 and 2012. N fertilization significantly increased WUE in 2010 and 2011, but not in 2012. The results indicated the following: (1 in this dryland farming system, increased N fertilization could raise wheat yield, and the drought-tolerant Changhan No. 58 showed a yield advantage in drought environments with high N fertilizer rates; (2 N application affected water consumption in different soil layers, and promoted wheat absorbing deeper soil water and so increased utilization of soil water; and (3 comprehensive consideration of yield and WUE of wheat indicated that the N rate of 270 kg/ha for Changhan No. 58 was better to avoid the risk of reduced production reduction due to lack of precipitation; however, under conditions of better soil moisture, the N rate of 180 kg/ha was more economic.

  15. Water consumption characteristics and water use efficiency of winter wheat under long-term nitrogen fertilization regimes in northwest China.

    Science.gov (United States)

    Zhong, Yangquanwei; Shangguan, Zhouping

    2014-01-01

    Water shortage and nitrogen (N) deficiency are the key factors limiting agricultural production in arid and semi-arid regions, and increasing agricultural productivity under rain-fed conditions often requires N management strategies. A field experiment on winter wheat (Triticum aestivum L.) was begun in 2004 to investigate effects of long-term N fertilization in the traditional pattern used for wheat in China. Using data collected over three consecutive years, commencing five years after the experiment began, the effects of N fertilization on wheat yield, evapotranspiration (ET) and water use efficiency (WUE, i.e. the ratio of grain yield to total ET in the crop growing season) were examined. In 2010, 2011 and 2012, N increased the yield of wheat cultivar Zhengmai No. 9023 by up to 61.1, 117.9 and 34.7%, respectively, and correspondingly in cultivar Changhan No. 58 by 58.4, 100.8 and 51.7%. N-applied treatments increased water consumption in different layers of 0-200 cm of soil and thus ET was significantly higher in N-applied than in non-N treatments. WUE was in the range of 1.0-2.09 kg/m3 for 2010, 2011 and 2012. N fertilization significantly increased WUE in 2010 and 2011, but not in 2012. The results indicated the following: (1) in this dryland farming system, increased N fertilization could raise wheat yield, and the drought-tolerant Changhan No. 58 showed a yield advantage in drought environments with high N fertilizer rates; (2) N application affected water consumption in different soil layers, and promoted wheat absorbing deeper soil water and so increased utilization of soil water; and (3) comprehensive consideration of yield and WUE of wheat indicated that the N rate of 270 kg/ha for Changhan No. 58 was better to avoid the risk of reduced production reduction due to lack of precipitation; however, under conditions of better soil moisture, the N rate of 180 kg/ha was more economic.

  16. [Distribution and enrichment characteristics of organic carbon and total nitrogen in mollisols under long-term fertilization].

    Science.gov (United States)

    Xu, Xiang-ru; Luo, Kun; Zhou, Bao-ku; Wang, Jing-kuan; Zhang, Wen-ju; Xu, Ming-gang

    2015-07-01

    The characteristics and changes of soil organic carbon (SOC) and total nitrogen (TN) in different size particles of soil under different agricultural practices are the basis for better understanding soil carbon sequestration of mollisols. Based on a 31-year long-term field experiment located at the Heilongjiang Academy of Agricultural Sciences (Harbin) , soil samples under six treatments were separated by size-fractionation method to explore changes and distribution of SOC and TN in coarse sand, fine sand, silt and clay from the top layer (0-20 cm) and subsurface layer (20-40 cm). Results showed that long-term application of manure (M) increased the percentages of SOC and TN in coarse sand and clay size fractions. In the top layer, application of nitrogen, phosphorus and potassium fertilizers combined with manure (NPKM) increased the percentages of SOC and TN in coarse sand by 191.3% and 179.3% compared with the control (CK), whereas M application increased the percentages of SOC and TN in clay by 45% and 47% respectively. For subsurface layers, the increase rates of SOC and TN in corresponding parts were lower than that in top layer. In the surface and subsurface layers, the percentages of SOC storage in silt size fraction accounted for 42%-63% and 48%-54%, TN storage accounted for 34%-59% and 41%-47%, respectively. The enrichment factors of SOC and TN in coarse sand and clay fractions of surface layers increased significantly under the treatments with manure. The SOC and TN enrichment factors were highest in the NPKM, being 2.30 and 1.88, respectively, while that in the clay fraction changed little in the subsurface layer.

  17. [Effect of long-term application of nitrogen fertilizer on the diversity of nitrifying genes (amoA and hao) in paddy soil].

    Science.gov (United States)

    Chen, Chun-lan; Wu, Min-na; Wei, Wen-xue

    2011-05-01

    The aim of this study was to determine the effect of long-term (16 years) application of nitrogen fertilizer on the diversity of nitrifying genes (amoA and hao) in paddy soil on the basis of long-term paddy field experimental station (started in 1990) located in Taoyuan, with the molecular approaches of PCR, constructing libraries and sequencing. The fertilizer was urea and no fertilizer was as control. The Shannon index showed that long-term application of nitrogen fertilizer made the diversity of amoA gene descend while no effect on the diversity of hao gene. The LIBSHUFF statistical analyses demonstrated that both amoA and hao libraries of CK and N treatments were significantly different from each other and the rarefaction curves of libraries failed to meet the plateaus indicating that there were lots kinds of genes haven't been detected. The results of blasting with GenBank and the phylogenetic tree showed that the amoA genes detected in our study had a similarity with the uncultured gene of amoA, which showed some similar to Nitrosospira. Otherwise, the hao genes cloned showed a relationship to the genes of cultured bacteria such as Silicibacteria, Nitrosospira and Methylococcus, and the hao genes found in the N treatment dominated in alpha-Proteobacteria. These results suggest that long-term fertilization of nitrogen had significant impacts on the diversity or community of amoA and hao genes.

  18. Effect of long-term compost and inorganic fertilizer application on background N2O and fertilizer-induced N2O emissions from an intensively cultivated soil.

    Science.gov (United States)

    Ding, Weixin; Luo, Jiafa; Li, Jie; Yu, Hongyan; Fan, Jianling; Liu, Deyan

    2013-11-01

    The influence of inorganic fertilizer and compost on background nitrous oxide (N2O) and fertilizer-induced N2O emissions were examined over a maize-wheat rotation year from June 2008 to May 2009 in a fluvo-aquic soil in Henan Province of China where a field experiment had been established in 1989 to evaluate the long-term effects of manure and fertilizer on soil organic status. The study involved five treatments: compost (OM), fertilizer NPK (nitrogen-phosphorus-potassium, NPK), half compost N plus half fertilizer N (HOM), fertilizer NK (NK), and control without any fertilizer (CK). The natural logarithms of the background N2O fluxes were significantly (P<0.05) correlated with soil temperature, but not with soil moisture, during the maize or wheat growing season. The 18-year application of compost alone and inorganic fertilizer not only significantly (P<0.05) increased soil organic carbon (SOC) by 152% and 10-43% (respectively), but also increased background N2O emissions by 106% and 48-76% (respectively) compared with the control. Total N in soils was a better indicator for predicting annual background N2O emission than SOC. The estimated emission factor (EF) of mineralized N, calculated by dividing annual N2O emission by mineralized N was 0.13-0.19%, significantly (P<0.05) lower than the EF of added N (0.30-0.39%). The annual N2O emission in the NPK, HOM and OM soils amended with 300 kg ha(-1) organic or inorganic N was 1427, 1325 and 1178 g N ha(-1), respectively. There was a significant (P<0.05) difference between the NPK and OM. The results of this study indicate that soil indigenous N was less efficiently converted into N2O compared with exogenous N. Increasing SOC by compost application, then partially increasing N supply to crops instead of adding inorganic N fertilizer, may be an effective measure to mitigate N2O emissions from arable soils in the North China plain. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Drainage, liming and fertilization of organic soils. 1. Long-term effects on acid/base relations

    Energy Technology Data Exchange (ETDEWEB)

    Braekke, F.H. [Norges Landbrukshoegskole, Aas (Norway). Dept. of Forest Sciences

    1999-06-01

    Long-term changes of the acid/base relations of organic soils after drainage, fertilization and/or liming at three experimental sites - two ombrogenous and one soligenous - in south-central Norway are discussed. These sites were drained, fertilized and/or limed in 1953-1956 and sampled in 1991-1992. Drainage at the ombrogenous sites caused: insignificant shifts of pH, higher bulk densities to 40 cm depth, higher ash percentage, higher contents of N and P to 20 cm depth and reduced concentrations of total Ca, K, Mg, Na, Al and Fe in soil layers deeper than 20 cm. The soligenous site was not effectively drained; despite this, pH dropped about 0.5 unit in the surface and subsurface soil layers of the control plots, while small changes were measured for most other soil variables. The suggested reason for the pH drop is limited sulphide oxidation in the upper 20 cm drained layer. Base saturation at actual soil pH, when all treatments were included, was estimated with good precision by four regressors: pH, extractable Al, extractable Fe and extractable Ca (R{sup 2} = 0.90-0.95). Similar models explained 97-99% of the variation in base saturation at soil pH = 7.0. The lime effects at the properly drained oligotrophic sites were proportional to applied doses; for pH to 40 cm, base saturation to 60 cm, and Ca concentration to 60 cm depth. At the less well-drained soligenous site, effects were limited to the upper 30 cm layer. Both drainage and liming caused higher cation exchange capacities and proper drainage seems to be a prerequisite for the liming effect. Estimated recovery of calcium to 60 cm depth was 64-79% at the ombrogenous sites and 42-46% at the soligenous site 28 refs, 3 figs, 8 tabs

  20. Genetic diversity of indigenous soybean-nodulating rhizobia in response to locally-based long term fertilization in a Mollisol of Northeast China.

    Science.gov (United States)

    Yan, Jun; Chen, WenFeng; Han, XiaoZeng; Wang, EnTao; Zou, WenXiu; Zhang, ZhiMing

    2017-01-01

    The influences of five different fertilizer treatments on diversity of rhizobia in soybean nodule were investigated in a long-term experiment with with four replicates: (1) control (without fertilization), (2) balanced NPK fertilizer (NPK), and (3-5) unbalanced chemical fertilizers without one of the major elements (NP, PK, and NK) in Mollisol in Northeast China. The highest soybean yield was observed in the NPK treatment. Total of 200 isolates were isolated and grouped into four Bradyrhizobium genospecies corresponding to B. japonicum, B. diazoefficiens, B. ottawaense and Bradyrhizobium sp. I, based upon the multilocus sequence analysis of 6 housekeeping genes. The Bradyrhizobium sp. I was extensively distributed throughout the study site and was recorded as the dominant soybean rhizobia (82.5-87.5%). Except the NK treatment, the other fertilizer treatments had no effect on rhizobial species composition. Compared with the CK treatment, all the fertilizer treatments decreased species richness, diversity and evenness. The soil organic carbon contents, available N content and pH were the key soil factors to rhizobial community structure. Results suggest that long-term fertilization can decrease rhizobial species diversity, while balanced fertilization with NPK is the most suitable fertilization regime if taking both soybean yields and rhizobial diversity into account.

  1. Evaluation of the CENTURY model using long-term fertilization trials under corn-wheat cropping systems in the typical croplands of China.

    Science.gov (United States)

    Cong, Rihuan; Wang, Xiujun; Xu, Minggang; Ogle, Stephen M; Parton, William J

    2014-01-01

    Soil organic matter models are widely used to study soil organic carbon (SOC) dynamics. Here, we used the CENTURY model to simulate SOC in wheat-corn cropping systems at three long-term fertilization trials. Our study indicates that CENTURY can simulate fertilization effects on SOC dynamics under different climate and soil conditions. The normalized root mean square error is less than 15% for all the treatments. Soil carbon presents various changes under different fertilization management. Treatment with straw return would enhance SOC to a relatively stable level whereas chemical fertilization affects SOC differently across the three sites. After running CENTURY over the period of 1990-2050, the SOC levels are predicted to increase from 31.8 to 52.1 Mg ha-1 across the three sites. We estimate that the carbon sequestration potential between 1990 and 2050 would be 9.4-35.7 Mg ha-1 under the current high manure application at the three sites. Analysis of SOC in each carbon pool indicates that long-term fertilization enhances the slow pool proportion but decreases the passive pool proportion. Model results suggest that change in the slow carbon pool is the major driver of the overall trends in SOC stocks under long-term fertilization.

  2. Draft Genome Sequence of Pseudomonas sp. Strain 2-92, a Biological Control Strain Isolated from a Field Plot Under Long-Term Mineral Fertilization.

    Science.gov (United States)

    Adam, Zaky; Tambong, James Tabi; Chen, Qing; Lewis, Christopher T; Lévesque, C André; Xu, Renlin

    2014-01-09

    Pseudomonas sp. strain 2-92, isolated from a Canadian field plot under long-term mineral fertilization, strongly inhibits the growth of Fusarium graminearum, Rhizoctonia solani, and Gaeumannomyces graminis. Here, we report the draft genome sequence of Pseudomonas sp. strain 2-92.

  3. Long-term N fertilization and conservation tillage practices conserve surface but not profile SOC stocks under semi-arid irrigated corn

    Science.gov (United States)

    No tillage (NT) and N fertilization can increase surface soil organic C (SOC) stocks, but the effects deeper in the soil profile are uncertain. Subsequent tillage could counter SOC stabilized through NT practices by disrupting soil aggregation and promoting decomposition. We followed a long-term ti...

  4. LONG TERM 32-YEAR-OLD APPLICATION OF FERTILIZERS FOR THE FERTILITY OF THE ORDINARY BLACK SOIL AND PRODUCTIVITY OF SUGAR BEET

    Directory of Open Access Journals (Sweden)

    Neshchadim N. N.

    2016-03-01

    Full Text Available The article deals with the effectiveness of mineral and organic fertilizers in long-term application (for more than thirty years according to the influence on the fertility of ordinary black soil of the Western Ciscaucasia and productivity of sugar beet. The investigations were carried out in the long-term stationary experiment laid on the experimental stationary section "Severokubanskaya agricultural experimental station" of P.P. Lukyanenko Krasnodar Agricultural Research Institute. The experiment was laid simultaneously in time and space in two ten-course crop rotations and combined grain-grass tilled. In the structure of sown areas sugar beet occupied 10% of crop rotation area and was placed after the winter wheat. During three rotations it was studied: 1- control without fertilizer with natural forming level of mineral nutrition; 2- minimal dose N21P26K16 3- medium dose N43P52K33 ; 4 - N43P52K33, 5- high dose N96P104K68; 6- organo-mineral system¹ N43P52K34 + 12 t/ha of manure; 7- organo-mineral system² N20P24K34 + II-III rotations tillage of straw crop + 6 t/ha of manure; 8- medium dose P52K33; 9- medium dose N43K33; 10- medium dose N43K52. The soil which is used by organo-mineral system with increased and high standards of mineral fertilizers had higher concentration of mineral nitrogen. Long systematic application of fertilizer had more noticeable effect on soil phosphorus regime. The provision of soil by exchange potassium tended to decline from rotation to rotation. If at the completion of the first rotation the content of this battery was at the level 362,0-433,0 mg / kg of soil, in 2010, these values were 356,0-405,0 mg / kg of soil, remaining at the level of increased and high provision characterized to ordinary black-soil. Fertilizers for crop rotation provided almost equal yield increase: in the first rotation - 4,9-16,0 t / ha in the second 5,3- 17,1, the third 6,1-15,5 t / ha. In the moderate favorable for moisture and

  5. Responses of bacterial and archaeal ammonia oxidizers to soil organic and fertilizer amendments under long-term management

    Energy Technology Data Exchange (ETDEWEB)

    Wessen, E.; Nyberg, K.; Jansson, J.K.; Hallin, S.

    2010-05-01

    Ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) co-exist in soil, but their relative distribution may vary depending on the environmental conditions. Effects of changes in soil organic matter and nutrient content on the AOB and AOA are poorly understood. Our aim was to compare effects of long-term soil organic matter depletion and amendments with labile (straw) and more recalcitrant (peat) organic matter, with and without easily plant-available nitrogen, on the activities, abundances and community structures of AOB and AOA. Soil was sampled from a long-term field site in Sweden that was established in 1956. The potential ammonia oxidation rates, the AOB and AOA amoA gene abundances and the community structures of both groups based on T-RFLP of amoA genes were determined. Straw amendment during 50 years had not altered any of the measured soil parameters, while the addition of peat resulted in a significant increase of soil organic carbon as well as a decrease in pH. Nitrogen fertilization alone resulted in a small decrease in soil pH, organic carbon and total nitrogen, but an increase in primary production. Type and amount of organic matter had an impact on the AOB and AOA community structures and the AOA abundance. Our findings confirmed that AOA are abundant in soil, but showed that under certain conditions the AOB dominate, suggesting niche differentiation between the two groups at the field site. The large differences in potential rates between treatments correlated to the AOA community size, indicating that they were functionally more important in the nitrification process than the AOB. The AOA abundance was positively related to addition of labile organic carbon, which supports the idea that AOA could have alternative growth strategies using organic carbon. The AOB community size varied little in contrast to that of the AOA. This indicates that the bacterial ammonia oxidizers as a group have a greater ecophysiological diversity and

  6. Changes in soil carbon and enzyme activity as a result of different long-term fertilization regimes in a greenhouse field.

    Science.gov (United States)

    Zhang, Lili; Chen, Wei; Burger, Martin; Yang, Lijie; Gong, Ping; Wu, Zhijie

    2015-01-01

    In order to discover the advantages and disadvantages of different fertilization regimes and identify the best management practice of fertilization in greenhouse fields, soil enzyme activities involved in carbon (C) transformations, soil chemical characteristics, and crop yields were monitored after long-term (20-year) fertilization regimes, including no fertilizer (CK), 300 kg N ha-1 and 600 kg N ha-1 as urea (N1 and N2), 75 Mg ha-1 horse manure compost (M), and M with either 300 or 600 kg N ha-1 urea (MN1 and MN2). Compared with CK, fertilization increased crop yields by 31% (N2) to 69% (MN1). However, compared with CK, inorganic fertilization (especially N2) also caused soil acidification and salinization. In the N2 treatment, soil total organic carbon (TOC) decreased from 14.1±0.27 g kg-1 at the beginning of the long-term experiment in 1988 to 12.6±0.11 g kg-1 (Pbiomass C and N. The fertilization regime of the MN1 treatment was identified as optimal because it produced the highest yields and increased soil quality, ensuring sustainability. The results suggest that inorganic fertilizer alone, especially in high amounts, in greenhouse fields is detrimental to soil quality.

  7. Sexual life and fertility desire in long-term HIV serodiscordant couples in Addis Ababa, Ethiopia: a grounded theory study

    Directory of Open Access Journals (Sweden)

    Hailemariam Tewodros G

    2012-10-01

    Full Text Available Abstract Background Even though remarkable progress has been achieved, HIV/AIDS continues to be a major global health priority. HIV discordant relationship is one of the emerging issues in HIV prevention endeavour. In Ethiopia, very little is known about HIV-serodiscordant couples particularly how they manage their sexual relationship and fertility desire. Therefore, we conduct this study with the aim of exploring the experiences of HIV discordant couples about their sexual life, and fertility desire in the context of long-term relationships in Addis Ababa, Ethiopia. Methods A grounded theory approach was employed using in-depth interviews among 36 informants in ART/PMTCT centers of three public hospitals, a health center and one PLHIV association in Addis Ababa. Theoretical sampling was used to recruit 28 clients who lived in a discordant relationship and eight health care providers as key informants. Data collection and analysis were undertaken simultaneously using a constant comparison. The analysis was facilitated using OpenCode software. Results A grounded theory pertaining to sexual life and desire to have a child among HIV discordant couples emerged as “maintaining the relationship” as a core category. Couples pass through a social process of struggle to maintain their relationship. The causal conditions for couples to enter into the process of struggle to maintain their relationship were collectively categorized as “Entering in-to a transition” (knowing HIV serostatus and this includes mismatch of desire to have a child, controversy on safe sex versus desire to have a child, and undeniable change in sexual desire and practice through time were the features in entering into-transition. Then after the transition, couples engaged in certain actions/strategies that are categorized as “dealing with discordancy” such as entertaining partner’s interest by scarifying once self interest to maintain their relationship. Conclusions

  8. Sexual life and fertility desire in long-term HIV serodiscordant couples in Addis Ababa, Ethiopia: a grounded theory study.

    Science.gov (United States)

    Hailemariam, Tewodros G; Kassie, Getnet M; Sisay, Mitike M

    2012-10-24

    Even though remarkable progress has been achieved, HIV/AIDS continues to be a major global health priority. HIV discordant relationship is one of the emerging issues in HIV prevention endeavour. In Ethiopia, very little is known about HIV-serodiscordant couples particularly how they manage their sexual relationship and fertility desire. Therefore, we conduct this study with the aim of exploring the experiences of HIV discordant couples about their sexual life, and fertility desire in the context of long-term relationships in Addis Ababa, Ethiopia. A grounded theory approach was employed using in-depth interviews among 36 informants in ART/PMTCT centers of three public hospitals, a health center and one PLHIV association in Addis Ababa. Theoretical sampling was used to recruit 28 clients who lived in a discordant relationship and eight health care providers as key informants. Data collection and analysis were undertaken simultaneously using a constant comparison. The analysis was facilitated using OpenCode software. A grounded theory pertaining to sexual life and desire to have a child among HIV discordant couples emerged as "maintaining the relationship" as a core category. Couples pass through a social process of struggle to maintain their relationship. The causal conditions for couples to enter into the process of struggle to maintain their relationship were collectively categorized as "Entering in-to a transition" (knowing HIV serostatus) and this includes mismatch of desire to have a child, controversy on safe sex versus desire to have a child, and undeniable change in sexual desire and practice through time were the features in entering into-transition. Then after the transition, couples engaged in certain actions/strategies that are categorized as "dealing with discordancy" such as entertaining partner's interest by scarifying once self interest to maintain their relationship. HIV discordant couples' relationship is filled with controversies of maintaining

  9. Long-term combined chemical and manure fertilizations increase soil organic carbon and total nitrogen in aggregate fractions at three typical cropland soils in China.

    Science.gov (United States)

    He, Y T; Zhang, W J; Xu, M G; Tong, X G; Sun, F X; Wang, J Z; Huang, S M; Zhu, P; He, X H

    2015-11-01

    Soil organic carbon (SOC), total nitrogen (TN), microbial biomass carbon (MBC) and nitrogen (MBN) are important factors of soil fertility. However, effects of the combined chemical fertilizer and organic manure or straw on these factors and their relationships are less addressed under long-term fertilizations. This study addressed changes in SOC, TN, MBC and MBN at 0-20 cm soil depth under three 17 years (September 1990-September 2007) long-term fertilization croplands along a heat and water gradient in China. Four soil physical fractions (coarse free and fine free particulate organic C, cfPOC and ffPOC; intra-microaggregate POC, iPOC; and mineral associated organic C, MOC) were examined under five fertilizations: unfertilized control, chemical nitrogen (N), phosphorus (P) and potassium (K) (NPK), NPK plus straw (NPKS, hereafter straw return), and NPK plus manure (NPKM and 1.5NPKM, hereafter manure). Compared with Control, manure significantly increased all tested parameters. SOC and TN in fractions distributed as MOC > iPOC > cfPOC > ffPOC with the highest increase in cfPOC (329.3%) and cfPTN (431.1%), and the lowest in MOC (40.8%) and MTN (45.4%) under manure. SOC significantly positively correlated with MBC, cfPOC, ffPOC, iPOC and MOC (R(2) = 0.51-0.84, P fertilization for improving soil fertility while straw return should take into account climate factors in Chinese croplands.

  10. Influence of long-term different fertilization on soil weed seed bank diversity of a paddy soil under rice/rape rotation

    Institute of Scientific and Technical Information of China (English)

    Wei FENG; Genxing PAN; Sheng QIANG; Ruhai LI; Jiguang WEI

    2008-01-01

    A long-term fertilized paddy field under rice/ rape rotation in the Taihu Lake Region was selected to investigate the dynamics of soil weed seed diversity.Four fertilizer treatments were performed,including non-fert-ilizer (NF),chemical fertilizer only (CF),chemical fert-ilizer combined with pig manure (CMF) and chemical fertilizer plus crop stalk (CSF).We recorded the seed numbers and crop yields,estimated the weed seed bank density and identified the kinds of weed seeds in the top-soil (0-15 cm) in the study area using a stereomicroscope.Based on the records,we analyzed the effect of long-term fertilization on soil weed seed bank diversity and the rela-tionship between weed seed diversity and crop yields.Comparing the four treatments,it was found that in the cultivating seasons of both rice and rape,the density of soil weed seed bank was the lowest with the treatment of chemical fertilizer plus crop stalk.Whereas,the total num-ber of species and the weed seed bank diversity was the highest.Furthermore,the crop yields were at maximum and kept constant with this treatment.There was a def-inite correlation between fertilizer treatment and soil weed seed bank diversity and crop yields.It was concluded that balancing the fertilizer management was helpful in main-taining soil weed seed bank diversity,increasing crop yields and alleviating crop yield fluctuation.Therefore,among the four fertilizer treatments,chemical fertilizer plus rice crop stalk treatment was the best one to stimulate the productivity of agricultural ecosystems and simulta-neously protect biodiversity.

  11. The use of total susceptibility in the analysis of long term PM10 (PM2.5) collected at Hungarian air quality monitoring stations

    Science.gov (United States)

    Márton, Emö; Domján, Ádám; Lautner, Péter; Szentmarjay, Tibor; Uram, János

    2013-04-01

    first, indicating that a sizable part of the magnetic grains is coming from nearby capitals rather than from more distant sources. We found no correlation between magnetic susceptibility and toxic metals. On the other hand the weaker vehicle traffic during week-ends, especially on Sundays is evident in the total susceptibilities, although it is also seen as a tendency in the mass of the pollutants and in the mass susceptibilities. While the generally used mass susceptibility seems to be useful as an indication for the heaviness of vehicle traffic in the area of the studied monitoring stations, it is a total failure for expressing correctly seasonal variations. The reason is that much more non-magnetic than magnetic pollutants are produced during heating season, especially by household heating with coal and wood. The consequence is that in the total susceptibility the higher production of the magnetic particles during heating season is evident, while in the mass susceptibility the trend is opposite, i.e. the magnetic pollution seems to be less intensive during heating season than otherwise. Acknowledgement: This work was financially supported by the Hungarian Scientific Research Fund (project no. OTKA K 75395).

  12. [Effects of long-term fertilization on organic carbon functional groups in black soil as revealed by synchrotron radiation soft X-ray near-edge absorption spectroscopy].

    Science.gov (United States)

    Wang, Nan; Wang, Shuai; Wang, Qing-He; Dong, Pei-Bo; Li, Cui-Lan; Zhang, Jin-Jing; Gao, Qiang; Zhao, Yi-Dong

    2012-10-01

    A 20 years (1984-2004) stationary field experiment was conducted to evaluate the effects of long-term application of chemical fertilizers (N or NPK) alone or in combination with low (0.125 kg x hm(-2)) or high dose of corn stalk (0.25 kg x hm(-2)) on organic carbon functional groups in black soil using synchrotron radiation soft X-ray near-edge absorption spectroscopy (C-1s NEXAFS). Compared with the control (CK) treatment, the aromatic C and the carboxyl C of soil increased, whereas the aliphatic C, the carbonyl C and the aliphatic C/aromatic C ratio decreased after the application of chemical fertilizer alone. After the application of chemical fertilizations in combined with corn stalk, the aromatic C decreased while the aliphatic C and the aliphatic C/aromatic C ratio increased as compared to N or NPK fertilizer treatment. And the change tendency was more obvious with the increase in the dose of corn stalk applied. Regardless of corn stalk application, the aromatic C, the aliphatic C, and the aliphatic C/aromatic C ratio were all higher for NPK than for N fertilizer treatment. The above results indicated that, compared with the no-fertilizer control treatment, the application of chemical fertilizers alone resulted in the relative proportion of aromatic compounds increased whereas that of aliphatic hydrocarbon compounds decreased. On the other hand, the relative proportion of the aliphatic hydrocarbon compounds was higher after the application of chemical fertilizers with than without corn stalk, with high than with low dose of corn stalk, and with NPK than with N fertilization. C-1s NEXAFS spectroscopy could characterize in situ the changes of organic carbon functional groups in soil under long-term stationary fertilization.

  13. Changes in soil carbon and enzyme activity as a result of different long-term fertilization regimes in a greenhouse field.

    Directory of Open Access Journals (Sweden)

    Lili Zhang

    Full Text Available In order to discover the advantages and disadvantages of different fertilization regimes and identify the best management practice of fertilization in greenhouse fields, soil enzyme activities involved in carbon (C transformations, soil chemical characteristics, and crop yields were monitored after long-term (20-year fertilization regimes, including no fertilizer (CK, 300 kg N ha-1 and 600 kg N ha-1 as urea (N1 and N2, 75 Mg ha-1 horse manure compost (M, and M with either 300 or 600 kg N ha-1 urea (MN1 and MN2. Compared with CK, fertilization increased crop yields by 31% (N2 to 69% (MN1. However, compared with CK, inorganic fertilization (especially N2 also caused soil acidification and salinization. In the N2 treatment, soil total organic carbon (TOC decreased from 14.1±0.27 g kg-1 at the beginning of the long-term experiment in 1988 to 12.6±0.11 g kg-1 (P<0.05. Compared to CK, N1 and N2 exhibited higher soil α-galactosidase and β-galactosidase activities, but lower soil α-glucosidase and β-glucosidase activities (P<0.05, indicating that inorganic fertilization had different impacts on these C transformation enzymes. Compared with CK, the M, MN1 and MN2 treatments exhibited higher enzyme activities, soil TOC, total nitrogen, dissolved organic C, and microbial biomass C and N. The fertilization regime of the MN1 treatment was identified as optimal because it produced the highest yields and increased soil quality, ensuring sustainability. The results suggest that inorganic fertilizer alone, especially in high amounts, in greenhouse fields is detrimental to soil quality.

  14. Bacterial Community Structure after Long-term Organic and Inorganic Fertilization Reveals Important Associations between Soil Nutrients and Specific Taxa Involved in Nutrient Transformations

    Science.gov (United States)

    Li, Fang; Chen, Lin; Zhang, Jiabao; Yin, Jun; Huang, Shaomin

    2017-01-01

    Fertilization has a large impact on the soil microbial communities, which play pivotal roles in soil biogeochemical cycling and ecological processes. While the effects of changes in nutrient availability due to fertilization on the soil microbial communities have received considerable attention, specific microbial taxa strongly influenced by long-term organic and inorganic fertilization, their potential effects and associations with soil nutrients remain unclear. Here, we use deep 16S amplicon sequencing to investigate bacterial community characteristics in a fluvo-aquic soil treated for 24 years with inorganic fertilizers and organics (manure and straw)-inorganic fertilizers, and uncover potential links between soil nutrient parameters and specific bacterial taxa. Our results showed that combined organic-inorganic fertilization increased soil organic carbon (SOC) and total nitrogen (TN) contents and altered bacterial community composition, while inorganic fertilization had little impact on soil nutrients and bacterial community composition. SOC and TN emerged as the major determinants of community composition. The abundances of specific taxa, especially Arenimonas, Gemmatimonas, and an unclassified member of Xanthomonadaceae, were substantially increased by organic-inorganic amendments rather than inorganic amendments only. A co-occurrence based network analysis demonstrated that SOC and TN had strong positive associations with some taxa (Gemmatimonas and the members of Acidobacteria subgroup 6, Myxococcales, Betaproteobacteria, and Bacteroidetes), and Gemmatimonas, Flavobacterium, and an unclassified member of Verrucomicrobia were identified as the keystone taxa. These specific taxa identified above are implicated in the decomposition of complex organic matters and soil carbon, nitrogen, and phosphorus transformations. The present work strengthens our current understanding of the soil microbial community structure and functions under long-term fertilization

  15. Seasonal differences in tillage draught on a sandy loam soil with long-term additions of animal manure and mineral fertilizers

    DEFF Research Database (Denmark)

    Peltre, Clément; Nyord, T.; Christensen, B.T.;

    2016-01-01

    Energy requirements for soil tillage are closely linked to soil properties, such as clay, water and soil organic carbon (SOC) contents. Long-term application of inorganic fertilizer and organic amendments affects SOC content but little is known about seasonal differences in tillage draught...... requirements of soils subject to contrasting nutrient management regimes. We assessed autumn and spring tillage draught following harvest of early-sown and timely sown winter wheat grown on a sandy loam in the Askov Long-Term Experiment on Animal Manure and Mineral Fertilizers. Draught force was related...... to soil texture, soil water and SOC content, shear strength and bulk density, nutrient management, and yield of the preceding winter wheat. Contents of clay and SOC ranged from 8.9 to 10.6% and from 0.98 to 1.36%, respectively. In the autumn and spring, SOC normalized by clay content explained 38 and 5...

  16. New strategies for submicron characterization the carbon binding of reactive minerals in long-term contrasting fertilized soils: implications for soil carbon storage

    Science.gov (United States)

    Xiao, Jian; He, Xinhua; Hao, Jialong; Zhou, Ying; Zheng, Lirong; Ran, Wei; Shen, Qirong; Yu, Guanghui

    2016-06-01

    Mineral binding is a major mechanism for soil carbon (C) stabilization. However, the submicron information about the in situ mechanisms of different fertilization practices affecting organo-mineral complexes and associated C preservation remains unclear. Here, we applied nano-scale secondary ion mass spectrometry (NanoSIMS), X-ray photoelectron spectroscopy (XPS), and X-ray absorption fine structure spectroscopy (XAFS) to examine differentiating effects of inorganic versus organic fertilization on interactions between highly reactive minerals and soil C preservation. To examine such interactions, soils and their extracted colloids were collected during a 24-year long-term fertilization period (1990-2014) (no fertilization, control; chemical nitrogen (N), phosphorus (P), and potassium (K) fertilization, NPK; and NPK plus swine manure fertilization, NPKM). The results for different fertilization conditions showed a ranked soil organic matter concentration with NPKM > NPK > control. Meanwhile, oxalate-extracted Al (Alo), Fe (Feo), short-range ordered Al (Alxps), Fe (Fexps), and dissolved organic carbon (DOC) ranked with NPKM > control > NPK, but the ratios of DOC / Alxps and DOC / Fexps ranked with NPKM > NPK > control. Compared with the NPK treatment, the NPKM treatment enhanced the C-binding loadings of Al and Fe minerals in soil colloids at the submicron scale. Furthermore, a greater concentration of highly reactive Al and Fe minerals was presented under NPKM than under NPK. Together, these submicron-scale findings suggest that both the reactive mineral species and their associations with C are differentially affected by 24-year long-term inorganic and organic fertilization.

  17. Effect of Long-Term Potassium Fertilization on Crop Yield and Potassium Efficiency and Balance Under Wheat-Maize Rotation in China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hui-Min; YANG Xue-Yun; HE Xin-Hua; XU Ming-Gang; HUANG Shao-Min; LIU Hua; WANG Bo-Ren

    2011-01-01

    Sustainable potassium (K) management at different soil sites requires understanding the relationships between crop productivity and long-term K fertilizations on a regional or national scale. We analyzed responses of grain yield of wheat (Triticum aestivum L.) and maize (Zea mays L.), K efficiency, and partial balance (difference between K input through fertilizer and K output in the aboveground biomass) during 15- (1990-2005) or 18-year (1990-2008) K fertilizations at five distinctive agroecological zones across China. Compared to the inorganic nitrogen (N) and phosphorus (P) fertilization, the inorganic NPK fertilization significantly increased grain yields of wheat (21%) and maize (16%-72%) at Qiyang and Changping, where soils have low exchangeable and non-exchangeable K contents, but not at (U)rǔmqi, Yangling and Zhengzhou, where soils have a high exchangeable and non-exchangeable K and/or low N/K ratio in crop plants. Compared to the inorganic NPK fertilization, the inorganic NPK (30% N) and organic manure (70% N) fertilization (NPKM) increased grain yields of wheat (14%-40%) and maize (9%-61%) at four sites, but not at Zhengzhou. For a productivity of wheat at 2-5 t ha-1 or maize at 3-6 t ha-1, 13-26 or 9-17 kg K ha-1 were required to produce 1.0 t wheat or maize. The NP fertilization resulted in the lowest negative partial K balance and accumulated 52 kg K ha-1 year-1 less than the NPK fertilization, which accumulated 28 kg ha-1 year-1 less K than the NPKM fertilization. A re-evaluation of the site-specific fertilization effects on N/K rat io in crop plants and soil K accumulation under current NPK and NPKM fertilization is urgently needed to increase both crop yield and K use efficiency at different agroecological zones across China.

  18. Influence of long-term mineral fertilization on metal contents and properties of soil samples taken from different locations in Hesse, Germany

    Science.gov (United States)

    Czarnecki, S.; Düring, R.-A.

    2015-01-01

    Essential and non-essential metals occur in soils as a result of weathering, industrial processes, fertilization, and atmospheric deposition. Badly adapted cultivation of agricultural soils (declining pH value, application of unsuitable fertilizers) can enhance the mobility of metals and thereby increase their concentrations in agricultural products. As the enrichment of metals in soils occurs over long time periods, monitoring of the long-term impact of fertilization is necessary to assess metal accumulation in agricultural soils. The main objective of this study was to test the effects of different mineral fertilizer variations on soil properties (pH, Corg, and cation exchange capacity (CEC)) and pseudo-total and mobile metal contents of soils after 14 years of fertilizer application and to determine residual effects of the fertilization 8 years after cessation of fertilizer treatment. Soil samples were taken from a field experiment which was carried out at four different locations (210, 260, 360, and 620 m above sea level) in Hesse, Germany. During the study, a significant decrease in soil pH and an evident increase in soil carbon content and cation exchange capacity with fertilization were determined. The CEC of the soils was closely related to their organic C contents. Moreover, pseudo- and mobile metal (Cd, Cu, Mn, Pb, Zn) contents in the soils increased due to application of 14 years of mineral fertilizer treatments (N, P, NP, and NPK) when compared to control plots. Eight years after termination of the fertilization in the soil samples taken from soil profiles of the fertilized plots (NPK) for monitoring the residual effects of the fertilizer application, a decrease of 82.6, 54.2, 48.5, 74.4, and 56.9% in pseudo-total Cd, Cu, Mn, Pb, and Zn contents, respectively, was determined.

  19. Soil organic carbon dynamics under long-term fertilization in a black soil of China: Evidence from stable C isotopes

    Science.gov (United States)

    Dou, Xiaolin; He, Ping; Zhu, Ping; Zhou, Wei

    2016-01-01

    Effects of different fertilizers on organic carbon (C) storage and turnover of soil fractions remains unclear. We combined soil fractionation with isotope analyses to examine soil organic carbon (SOC) dynamics after 25 years of fertilization. Five types of soil samples including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, N; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into four aggregate sizes (>2000 μm, 2000–250 μm, 250–53 μm, and 250 μm aggregates but reduced SOC storage in <250 μm aggregates due to SOC changes in LF and iPOM. PMID:26898121

  20. Long-term nitrogen fertilization of paddy soil shifts iron-reducing microbial community revealed by RNA-(13)C-acetate probing coupled with pyrosequencing.

    Science.gov (United States)

    Ding, Long-Jun; Su, Jian-Qiang; Xu, Hui-Juan; Jia, Zhong-Jun; Zhu, Yong-Guan

    2015-03-01

    Iron reduction is an important biogeochemical process in paddy soils, yet little is known about the microbial coupling between nitrogen and iron reduction. Here, we investigated the shift of acetate-metabolizing iron-reducers under long-term nitrogen fertilization using (13)C-acetate-based ribosomal RNA (rRNA)-stable isotope probing (SIP) and pyrosequencing in an incubation experiment, and the shift of putative iron-reducers in original field samples were investigated by 16S rRNA gene-based pyrosequencing. During SIP incubations, in the presence of iron(III) oxyhydroxides, more iron(II) formation and less methane production were detected in nitrogen-fertilized (N) compared with non-fertilized (NF) soil. In (13)C-rRNA from microcosms amended with ferrihydrite (FER), Geobacter spp. were the important active iron-reducers in both soils, and labeled to a greater extent in N (31% of the bacterial classified sequences) than NF soils (11%). Pyrosequencing of the total 16S rRNA transcripts from microcosms at the whole community level further revealed hitherto unknown metabolisms of potential FER reduction by microorganisms including Pseudomonas and Solibacillus spp. in N soil, Dechloromonas, Clostridium, Bacillus and Solibacillus spp. in NF soil. Goethite (GOE) amendment stimulated Geobacter spp. to a lesser extent in both soils compared with FER treatment. Pseudomonas spp. in the N soil and Clostridium spp. in the NF soil may also be involved in GOE reduction. Pyrosequencing results from field samples showed that Geobacter spp. were the most abundant putative iron-reducers in both soils, and significantly stimulated by long-term nitrogen fertilization. Overall, for the first time, we demonstrate that long-term nitrogen fertilization promotes iron(III) reduction and modulates iron-reducing bacterial community in paddy soils.

  1. Soil organic carbon dynamics under long-term fertilization in a black soil of China: Evidence from stable C isotopes.

    Science.gov (United States)

    Dou, Xiaolin; He, Ping; Zhu, Ping; Zhou, Wei

    2016-01-01

    Effects of different fertilizers on organic carbon (C) storage and turnover of soil fractions remains unclear. We combined soil fractionation with isotope analyses to examine soil organic carbon (SOC) dynamics after 25 years of fertilization. Five types of soil samples including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, N; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into four aggregate sizes (>2000 μm, 2000-250 μm, 250-53 μm, and organic matter (iPOM), and mineral-associated organic matter (mSOM). Physical fractionation showed the iPOM fraction of aggregates dominated C storage, averaging 76.87% of SOC storage. Overall, application of N and NPK fertilizers cannot significantly increase the SOC storage but enhanced C in mSOM of aggregates, whereas MNPK fertilizer resulted in the greatest amount of SOC storage (about 5221.5 g C m(2)) because of the enhanced SOC in LF, iPOM and mSOM of each aggregate. The SNPK fertilizer increased SOC storage in >250 μm aggregates but reduced SOC storage in <250 μm aggregates due to SOC changes in LF and iPOM.

  2. Mineral vs. organic amendments: microbial community structure, activity and abundance of agriculturally relevant microbes are driven by long-term fertilization strategies

    Directory of Open Access Journals (Sweden)

    Davide Francioli

    2016-09-01

    Full Text Available Soil management is fundamental to all agricultural systems and fertilization practices have contributed substantially to the impressive increases in food production. Despite the pivotal role of soil microorganisms in agro-ecosystems, we still have a limited understanding of the complex response of the soil microbiota to organic and mineral fertilization in the very long-term. Here we report the effects of different fertilization regimes (mineral, organic and combined mineral and organic fertilization, carried out for more than a century, on the structure and activity of the soil microbiome. Organic matter content, nutrient concentrations and microbial biomass carbon were significantly increased by mineral, and even more strongly by organic fertilization. Pyrosequencing revealed significant differences between the structures of bacterial and fungal soil communities associated to each fertilization regime. Organic fertilization increased bacterial diversity, and stimulated microbial groups (Firmicutes, Proteobacteria and Zygomycota that are known to prefer nutrient-rich environments, and that are involved in the degradation of complex organic compounds. In contrast, soils not receiving manure harbored distinct microbial communities enriched in oligotrophic organisms adapted to nutrient-limited environments, as Acidobacteria. The fertilization regime also affected the relative abundances of plant beneficial and detrimental microbial taxa, which may influence productivity and stability of the agroecosystem. As expected, the activity of microbial exoenzymes involved in carbon, nitrogen and phosphorous mineralization were enhanced by both types of fertilization. However, in contrast to comparable studies, the highest chitinase and phosphatase activities were observed in the solely mineral fertilized soil. Interestingly, these two enzymes showed also a particular high biomass-specific activities and a strong negative relation with soil pH. As many soil

  3. Mineral vs. Organic Amendments: Microbial Community Structure, Activity and Abundance of Agriculturally Relevant Microbes Are Driven by Long-Term Fertilization Strategies.

    Science.gov (United States)

    Francioli, Davide; Schulz, Elke; Lentendu, Guillaume; Wubet, Tesfaye; Buscot, François; Reitz, Thomas

    2016-01-01

    Soil management is fundamental to all agricultural systems and fertilization practices have contributed substantially to the impressive increases in food production. Despite the pivotal role of soil microorganisms in agro-ecosystems, we still have a limited understanding of the complex response of the soil microbiota to organic and mineral fertilization in the very long-term. Here, we report the effects of different fertilization regimes (mineral, organic and combined mineral and organic fertilization), carried out for more than a century, on the structure and activity of the soil microbiome. Organic matter content, nutrient concentrations, and microbial biomass carbon were significantly increased by mineral, and even more strongly by organic fertilization. Pyrosequencing revealed significant differences between the structures of bacterial and fungal soil communities associated to each fertilization regime. Organic fertilization increased bacterial diversity, and stimulated microbial groups (Firmicutes, Proteobacteria, and Zygomycota) that are known to prefer nutrient-rich environments, and that are involved in the degradation of complex organic compounds. In contrast, soils not receiving manure harbored distinct microbial communities enriched in oligotrophic organisms adapted to nutrient-limited environments, as Acidobacteria. The fertilization regime also affected the relative abundances of plant beneficial and detrimental microbial taxa, which may influence productivity and stability of the agroecosystem. As expected, the activity of microbial exoenzymes involved in carbon, nitrogen, and phosphorous mineralization were enhanced by both types of fertilization. However, in contrast to comparable studies, the highest chitinase and phosphatase activities were observed in the solely mineral fertilized soil. Interestingly, these two enzymes showed also a particular high biomass-specific activities and a strong negative relation with soil pH. As many soil parameters

  4. [Effect of Long-term Fertilizer Application on the Stability of Organic Carbon in Particle Size Fractions of a Paddy Soil in Zhejiang Province, China].

    Science.gov (United States)

    Mao, Xia-li; Lu, Kou-ping; Sun, Tao; Zhang, Xiao-kai; He, Li-zhi; Wang, Hai-long

    2015-05-01

    Effects of chemical fertilizers and organic manure on the soil organic carbon (SOC) content in particle size fractions of paddy soil were investigated in a 17-year long-term fertilization field experiment in Zhejiang Province, China. The inherent chemical composition of silt- and clay-associated SOC was evaluated with solid-state 13C-NMR spectroscopy. Compared to CK (no fertilizer treatment), NPKRS (NPK fertilizers plus rice straw) , NPKOM (NPK fertilizers plus organic manure) , NPK (NPK fertilizers) and OM (organic manure alone) treatments significantly (P fertilizers alone, combined application of organic amendments and NPK fertilizers facilitated the storage of newly sequestered SOC in silt- and clay-sized fractions, which could be more conducive to the stability of SOC. Based on 13C-NMR spectra, both silt and clay fractions were composed of Alkyl-C, O-alkyl-C, Aromatic-C and carbonyl-C. Changes in the relative proportion of different C species were observed between silt and clay fractions: the clay fraction had relatively more Alkyl-C, carbonyl-C and less O-alkyl-C, Aromatic-C than those in the silt fraction. This might be ascribed to the fact that the organic matter complexed with clay was dominated by microbial products, whereas the silt appeared to be rich in aromatic residues derived from plants. The spectra also showed that the relative proportion of different C species was modified by fertilization practices. In comparison with organic amendments alone, the relative proportion of Alkyl-C was decreased by 9.1%-11.9% and 13.7%-19.9% under combined application of organic amendments and chemical fertilizers, for silt and clay, respectively, and that of O-alkyl-C was increased by 2.9%-6.3% and 13.4%-22.1%, respectively. These results indicated that NPKOM and NPKRS treatments reduced the decomposition rate of SOC. The aromaticity, hydrophobicity and, hence, chemical recalcitrance of silt- and clay-associated SOC in the NPK fertilizer treatments were lower than

  5. Short-term and long-term effects of weed control and fertilization on growth and wood anatomy of a Populus deltoides clone

    Directory of Open Access Journals (Sweden)

    Silvia Estela Monteoliva

    2015-04-01

    Full Text Available Aims of study: The short- and long-term effects of weed control and fertilization on growth and wood anatomy of 10-y-old Populus deltoides were investigated. Weed control and fertilization usually leads to an increase the growth rate of trees, and consequently, a possible modification in the quality of produced wood. Area of study: We analyzed trees from an experimental plantation in Buenos Aires, Argentina (34° 50’ S Lat; 60° 30’ W Long. Methods: 32 trees from three treatments: mechanical weed control (M, chemical and mechanical weed control (CHM and fertilized plus chemical and mechanical weed control (CHM-F were analyzed. Basal area, fibre morphology, cell wall area and vessel size were measured in the growth ring 1, 3 and 10. Results: differences on wood anatomy among treatments were mainly observed at the third year (short-term effect. Long-term negative effects were not observed. Fertilized trees had greater proportion and quality of wood closer to pith. Research highlights: fibre and vessel differences seen in CHM and CHM-F compared to controls in year 3 could be interpreted as evidence of maturation in cambial development (thicker, longer and wider fibres and greater vessels. The CHM-F treatment had a greater proportion of wood that showed characteristics of more mature wood.

  6. Characterizing differences in the phosphorus activation coefficient of three typical cropland soils and the influencing factors under long-term fertilization.

    Science.gov (United States)

    Wu, Qihua; Zhang, Shuxiang; Zhu, Ping; Huang, Shaomin; Wang, Boren; Zhao, LinPing; Xu, Minggang

    2017-01-01

    The phosphorus activation coefficient (PAC, the ratio of available P to total P) is an important indicator of soil P availability and the transformation of P fractions. Understanding the details of the PAC is useful to estimate soil available P status and to provide P management guidance. In this research, soils from five long-term (23 years) fertilization treatments in three croplands were selected to examine the relationships between the PAC and P fractions and to analyse the influencing factors. PAC was affected by both soil types and fertilization treatments. Compared to the unfertilized control (CK) treatment, long-term P application significantly increased the PAC, all of the inorganic P (Pi) fractions and most of the organic P (Po) fractions in all the three soils, particularly in chemical fertilizer combined with manure treatment (NPKM). The PAC was significantly correlated to all of the Pi fractions proportions (Pvariance partitioning analysis showed that more variance of PAC is explained by soil factors (29.53%) than by P input (0.19%) and climate (0.25%) factors. Our findings demonstrate that P application increased the PAC by changing the Co content and the proportion of P fractions. Moreover, soil factors were the most important drivers of P transformations, and NPKM was optimal for improving soil fertility in Chinese croplands.

  7. Long-term organic-inorganic fertilization ensures great soil productivity and bacterial diversity after natural-to-agricultural ecosystem conversion.

    Science.gov (United States)

    Xun, Weibing; Xu, Zhihui; Li, Wei; Ren, Yi; Huang, Ting; Ran, Wei; Wang, Boren; Shen, Qirong; Zhang, Ruifu

    2016-09-01

    Natural ecosystems comprise the planet's wild plant and animal resources, but large tracts of land have been converted to agroecosystems to support the demand for agricultural products. This conversion limits the number of plant species and decreases the soil biological diversity. Here we used high-throughput 16S rRNA gene sequencing to evaluate the responses of soil bacterial communities in long-term converted and fertilized red soils (a type of Ferralic Cambisol). We observed that soil bacterial diversity was strongly affected by different types of fertilization management. Oligotrophic bacterial taxa demonstrated large relative abundances in chemically fertilized soil, whereas copiotrophic bacterial taxa were found in large relative abundances in organically fertilized and fallow management soils. Only organic-inorganic fertilization exhibited the same local taxonomic and phylogenetic diversity as that of a natural ecosystem. However, the independent use of organic or inorganic fertilizer reduced local taxonomic and phylogenetic diversity and caused biotic homogenization. This study demonstrated that the homogenization of bacterial communities caused by natural-to-agricultural ecosystem conversion can be mitigated by employing rational organic-inorganic fertilization management.

  8. Studies on nutrient uptake of rice and characteristics of soil microorganisms in a long-term fertilization experiments for irrigated rice

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qi-chun; WANG Guang-huo

    2005-01-01

    The ecosystem characteristics of soil microorganism and the nutrient uptake of irrigated rice were investigated in a split-block experiment with different fertilization treatments, including control (no fertilizer application), PK, NK, NP, NPK fertilization, in the main block, and conventional rice and hybrid rice comparison, in the sub block. Average data of five treatments in five years indicated that the indigenous N supply (INS) capacity ranged from 32.72 to 93.21 kg/ha; that indigenous P supply (IPS)capacity ranged from 7.42 to 32.25 kg/ha; and that indigenous K supply (IKS) capacity ranged from 16.24 to 140.51 kg/ha, which showed that soil available nutrient pool depletion might occur very fast and that P, K deficiency has become a constraint to increasing yields of consecutive crops grown without fertilizer application. It was found that soil nutrient deficiency and unbalanced fertilization to rice crop had negative effect on the diversity of the microbial community and total microbial biomass in the soil.The long-term fertilizer experiment (LTFE) also showed that balanced application of N, P and K promoted microbial biomass growth and improvement of community composition. Unbalanced fertilization reduced microbial N and increased C/N ratio of the microbial biomass. Compared with inbred rice, hybrid rice behavior is characterized by physiological advantage in nutrient uptake and lower internal K use efficiency.

  9. Arbuscular mycorrhizal fungus enhances P acquisition of wheat (Triticum aestivum L.) in a sandy loam soil with long-term inorganic fertilization regime.

    Science.gov (United States)

    Hu, Junli; Lin, Xiangui; Wang, Junhua; Cui, Xiangchao; Dai, Jue; Chu, Haiyan; Zhang, Jiabao

    2010-10-01

    The P efficiency, crop yield, and response of wheat to arbuscular mycorrhizal fungus (AMF) Glomus caledonium were tested in an experimental field with long-term (19 years) fertilizer management. The experiment included five fertilizer treatments: organic amendment (OA), half organic amendment plus half mineral fertilizer (1/2 OM), mineral fertilizer NPK, mineral fertilizer NK, and the control (without fertilization). AMF inoculation responsiveness (MIR) of wheat plants at acquiring P were estimated by comparing plants grown in unsterilized soil inoculated with G. caledonium and in untreated soil containing indigenous AMF. Without AMF inoculation, higher crop yields but lower colonization rates were observed in the NPK and two OA-inputted treatments, and NPK had significantly (P soils and thereby P acquisition of wheat plants compared with OA and 1/2 OM. G. caledonium inoculation significantly (P soil alkaline phosphatase (ALP) activity, only with the NPK treatment. This gave an MIR of ca. 45% on total P acquisition of wheat plants. There were no other remarkable MIRs. It suggested that the MIR is determined by soil available P status, and rational combination of AMF with chemical NPK fertilizer can compensate for organic amendments by improving P-acquisition efficiency in arable soils.

  10. Long-term incorporation of manure with chemical fertilizers reduced total nitrogen loss in rain-fed cropping systems

    Science.gov (United States)

    Duan, Yinghua; Xu, Minggang; Gao, Suduan; Liu, Hua; Huang, Shaomin; Wang, Boren

    2016-09-01

    Improving soil fertility/productivity and reducing environmental impact of nitrogen (N) fertilization are essential for sustainable agriculture. Quantifying the contribution of various fertilization regimes to soil N storage and loss has been lacking in a wide range of spatiotemporal scales. Based on data collected from field experiments at three typical agricultural zones in China, soil N dynamics and N changes in soil profile (0–100 cm) were examined during 1990–2009 under chemical fertilization, manure incorporation with fertilizer, and fertilizer with straw return treatments. We employed a mass balance approach to estimate the N loss to the environment after taking into account soil N change. Results showed a significant increase in soil N storage under manure incorporation treatments, accompanied with the lowest N loss (ave.20–24% of total N input) compared to all other treatments (ave.35–63%). Both soil N distribution and mass balance data suggested higher leaching risk from chemical fertilization in acidic soil of southern China with higher precipitation than the other two sites. This research concludes that manure incorporation with chemical fertilizer not only can achieve high N use efficiency and improve soil fertility, but also leads to the lowest total N loss or damage to the environment.

  11. Long-term incorporation of manure with chemical fertilizers reduced total nitrogen loss in rain-fed cropping systems

    Science.gov (United States)

    Duan, Yinghua; Xu, Minggang; Gao, Suduan; Liu, Hua; Huang, Shaomin; Wang, Boren

    2016-01-01

    Improving soil fertility/productivity and reducing environmental impact of nitrogen (N) fertilization are essential for sustainable agriculture. Quantifying the contribution of various fertilization regimes to soil N storage and loss has been lacking in a wide range of spatiotemporal scales. Based on data collected from field experiments at three typical agricultural zones in China, soil N dynamics and N changes in soil profile (0–100 cm) were examined during 1990–2009 under chemical fertilization, manure incorporation with fertilizer, and fertilizer with straw return treatments. We employed a mass balance approach to estimate the N loss to the environment after taking into account soil N change. Results showed a significant increase in soil N storage under manure incorporation treatments, accompanied with the lowest N loss (ave.20–24% of total N input) compared to all other treatments (ave.35–63%). Both soil N distribution and mass balance data suggested higher leaching risk from chemical fertilization in acidic soil of southern China with higher precipitation than the other two sites. This research concludes that manure incorporation with chemical fertilizer not only can achieve high N use efficiency and improve soil fertility, but also leads to the lowest total N loss or damage to the environment. PMID:27650801

  12. How does education change the relationship between fertility and age-dependency under environmental constraints? A long-term simulation exercise

    Directory of Open Access Journals (Sweden)

    Erich Striessnig

    2014-02-01

    Full Text Available Background: When asked what a desirable fertility level for populations might be, most politicians, journalists, and even social scientists would say it is around two children per woman, a level that has been labelled by demographers "replacement-level fertility." The reasons given for considering this level of fertility as something to aim at usually include maintaining the size of the labour force and stabilizing the old-age-dependency ratio. Objective: In this paper, we scrutinize this wide-spread view by introducing education in addition to age and sex as a further relevant source of observable population heterogeneity. We consider several criteria for assessing the long-term implications of alternative fertility levels and present numerical simulations with a view on minimizing the education-weighted total dependency ratio and complement this with the goal of reducing the amount of greenhouse gas emission in the context of climate change. Methods: We perform thousands of alternative simulations for different fertility levels (assumed to be constant over time starting from empirically given population structures and derive the rate of fertility which yields the lowest level of our education-weighted dependency ratio. We study the sensitivity of our results to different parameter values and choose to focus on the actual populations of Europe and China over the course of the 21st century. Results: The results show that when education is assumed to present a cost at young age and results in higher productivity during adult age, then the fertility rate that on the long run keeps dependency at a minimum turns out to lie well below replacement fertility both in Europe and in China under a set of plausible assumptions. The optimal fertility level falls even lower when climate change is factored in as well. Conclusions: We conclude that there is nothing magical or particularly desirable about replacement level fertility.

  13. Long-term effect of mineral fertilizers and amendments on microbial dynamics in an alfisol of Western Himalayas.

    Science.gov (United States)

    Mahajan, S; Kanwar, S S; Sharma, S P

    2007-03-01

    The microbial dynamics expressed in terms of culturable microbial populations i.e. bacteria, fungi, actinomycetes and Azotobacter were measured after 33 years of continuous application of mineral fertilizers and amendments to an acid alfisol. The bacterial, fungal and Azotobacter populations were maximum in plots treated with mineral fertilizers and FYM (100%NPK+FYM) while actinomycetes population was maximum in mineral fertilizes and lime treated plots (100%NPK+Lime). The bacterial population decreased and fungal population increased with increasing levels of NPK i.e. from 50% to 150%NPK. Bacillus species of bacteria and Gliocladium, Aspergillus and Rhizopus species of fungi were the main dominating culturable microorganisms in all the treatments. The FYM and lime amended plots sustained crop productivity and microbial populations at higher levels than rest of the mineral fertilizer treatments. The nitrogenous fertilizers alone had the most deleterious effect on crop productivity and the biological soil environment.

  14. Effects of long-term amendment of organic manure and nitrogen fertilizer on nitrous oxide emission in a sandy loam soil

    Institute of Scientific and Technical Information of China (English)

    DING Wei-xin; MENG Lei; CAI Zu-cong; HAN Feng-xiang

    2007-01-01

    To understand the effects of long-term amendment of organic manure and N fertilizer on N2O emission in the North China Plain,a laboratory incubation at different temperatures and soil moistures were carried out using soils treated with organic manure (OM),half organic manure plus half fertilizer N (HOM), fertilizer NPK (NPK), fertilizer NP (NP), fertilizer NK (NK), fertilizer PK (NK) and control (CK) since 1989. Cumulative N2O emission in OM soil during the 17 d incubation period was slightly higher than in NPK soil under optimum nitrification conditions (25C and 60% water-filled pore space, WFPS), but more than twice under the optimum denitrification conditions (35C and 90% WFPS). N2O produced by denitrification was 2.1-2.3 times greater than that by nitrification in OM and HOM soils, but only 1.5 times greater in NPK and NP soils. These results implied that the long-term amendment of organic manure could significantly increase the N2O emission via denitrification in OM soil as compared to NPK soil. This is quite different from field measurement between OM soil and NPK soil. Substantial inhibition of the formation of anaerobic environment for denitrification in field might result in no marked difference in N2O emission between OM and NPK soils. This is due in part to more rapid oxygen diffusion in coarse textured soils than consumption by aerobic microbes until WFPS was 75% and to low easily decomposed organic C of organic manure. This finding suggested that addition of organic manure in the tested sandy loam might be a good management option since it seldom caused a burst of N2O emission but sequestered atmospheric C and maintained efficiently applied N in soil.

  15. Long-Term Effect of Organic and Mineral Fertilization on Soil Physical Properties Under Greenhouse and Outdoor Management Practices

    Institute of Scientific and Technical Information of China (English)

    J. F. HERENCIA; P. A. GARC(I)A-GALAV(I)S; C. MAQUEDA

    2011-01-01

    To evaluate the use of organic amendments as an alternative to conventional fertilization,a 10-year experiment on a loam soil was conducted under a crop rotation system in both greenhouse and outdoor plots applied with chemical fertilizers (NPK) and vegetal compost (organic fertilizer) in the Guadalquivir River Valley,Spain.The effect of these two different fertilization regimes on the soil physical properties was evaluated.Soil organic carbon (OC),soil bulk density (BD),soil water retention (WR),available water content (AWC),aggregate stability (AS),and soil physical quality (Dexter's index,S) were determined.The use of organic fertilizer increased OC and resulted in a significant increase in AS and a decrease in BD compared to the mineral fertilizer application in both greenhouse and outdoor plots.The outdoor plots showed the lowest BD values whereas the greenhouse plots showed the highest AS values.In the last years of the 10-year experiment the S parameter was significantly higher in organic fertilizer plots,especially for greenhouse plots.At the end of the study period,there were no significant differences in WR at field capacity (FC) between treatments in both systems; the AWC was also similar in the greenhouse plots but higher in the mineral outdoor plots.In mineral fertilizer treatments,a small improvement in the physical properties was also observed due to the utilization of less aggressive tillage compared with the previous intensive cropping system.Physical soil properties were correlated with soil OC.The sustainable management techniques such as the use of organic amendments and low or no tillage improved soil physical properties,despite the differences in management that logically significantly affected the results.

  16. Long-term effects of fertilization on soil organic carbon changes in continuous corn of northeast China: RothC model simulations.

    Science.gov (United States)

    Yang, X M; Zhang, X P; Fang, H J; Zhu, P; Ren, J; Wang, L C

    2003-10-01

    Soil organic C (SOC) content can increase by managing land use practices in which the rates of organic C input exceed those of organic C mineralization. Understanding the changes in SOC content of Black soils (mainly Typic Halpudoll) in northeast China is necessary for sustainable using of soil resources there. We used the RothC model to estimate SOC levels of Black soils under monoculture cropping corn in a long-term fertilization trial at Gongzhuling, Jilin Province, China. The model outputs for the changes in SOC were compared with measured data in this long-term fertilization/manure trial. The sound performance of model in simulating SOC changes suggests that RothC is feasible with Black soils in the temperate climatic region of northeast China. The modeled and measured results indicated that the treatment without fertilizer/farmyard manure (FYM) addition led to a continuous decline in SOC during the study period and N and NPK fertilization were inadequate to maintain the SOC levels in the plow layer (upper 20 cm) unless FYM was added under the current conventional management associated with no above-ground crop residues returning into the soil. Soil organic carbon could follow the same path of decline if the same management practices are maintained. Model results indicate that returning above-ground crop residues to the soil from 2002 to 2022 would increase SOC by 26% for the treatment without fertilization addition, 40% for N treatment, 45% for NPK treatment, and 38% and 46% for N and NPK treatments with FYM addition, compared to the levels in the corresponding treatments in 2002. The simulation results suggest that the RothC model is a feasible tool to assess SOC trend under different management practices, and returning above-ground crop residues into the soil would lead to a remarkable increase in SOC of Black soils in the region.

  17. Long Term Sugarcane Crop Residue Retention Offers Limited Potential to Reduce Nitrogen Fertilizer Rates in Australian Wet Tropical Environments.

    Science.gov (United States)

    Meier, Elizabeth A; Thorburn, Peter J

    2016-01-01

    The warming of world climate systems is driving interest in the mitigation of greenhouse gas (GHG) emissions. In the agricultural sector, practices that mitigate GHG emissions include those that (1) reduce emissions [e.g., those that reduce nitrous oxide (N2O) emissions by avoiding excess nitrogen (N) fertilizer application], and (2) increase soil organic carbon (SOC) stocks (e.g., by retaining instead of burning crop residues). Sugarcane is a globally important crop that can have substantial inputs of N fertilizer and which produces large amounts of crop residues ('trash'). Management of N fertilizer and trash affects soil carbon and nitrogen cycling, and hence GHG emissions. Trash has historically been burned at harvest, but increasingly is being retained on the soil surface as a 'trash blanket' in many countries. The potential for trash retention to alter N fertilizer requirements and sequester SOC was investigated in this study. The APSIM model was calibrated with data from field and laboratory studies of trash decomposition in the wet tropics of northern Australia. APSIM was then validated against four independent data sets, before simulating location × soil × fertilizer × trash management scenarios. Soil carbon increased in trash blanketed soils relative to SOC in soils with burnt trash. However, further increases in SOC for the study region may be limited because the SOC in trash blanketed soils could be approaching equilibrium; future GHG mitigation efforts in this region should therefore focus on N fertilizer management. Simulated N fertilizer rates were able to be reduced from conventional rates regardless of trash management, because of low yield potential in the wet tropics. For crops subjected to continuous trash blanketing, there was substantial immobilization of N in decomposing trash so conventional N fertilizer rates were required for up to 24 years after trash blanketing commenced. After this period, there was potential to reduce N fertilizer

  18. Evaluation of the leucine incorporation technique for detection of pollution-induced community tolerance to copper in a long-term agricultural field trial with urban waste fertilizers

    DEFF Research Database (Denmark)

    Lekfeldt, Jonas Duus Stevens; Magid, Jakob; Holm, Peter Engelund

    2014-01-01

    Copper (Cu) is known to accumulate in agricultural soils receiving urban waste products as fertilizers. We here report the use of the leucine incorporation technique to determine pollution-induced community tolerance (Leu-PICT) to Cu in a long-term agricultural field trial. A significantly...... speciation and bioavailability artifacts during Leu-PICT detection. Hence, the agricultural application of urban wastes (sewage sludge or composted municipal waste) simulating more than 100 years of use did not result in sufficient accumulation of Cu to select for Cu resistance. Our findings also have...

  19. Effect of Long-Term Application of K Fertilizer and Wheat Straw to Soil on Crop Yield and Soil K Under Different Planting Systems

    Institute of Scientific and Technical Information of China (English)

    TAN De-shui; JIN Ji-yun; HUANG Shao-wen; LI Shu-tian; HE Ping

    2007-01-01

    Effect of application of K fertilizer and wheat straw to soil on crop yield and status of soil K in the plough layer under different planting systems was studied. The experiments on long-term application of K fertilizer and wheat straw to soil in Hebei fluvo aquic soil and Shanxi brown soil in northern China were begun in 1992. The results showed that K fertilizer and straw could improve the yields of wheat and maize with the order of NPK + St > NPK > NP + St > NP, and treatment of K fertilizer made a significant difference to NP, and the efficiency of K fertilizer in maize was higher than in wheat under rotation system of Hebei. In contrast with Shanxi, the wastage of soil potassium was a more serious issue in the rotation system in Hebei, only treatment of NPK + St showed a surplus of potassium and the others showed a wane. K fertilizer and straw could improve the content of water-soluble K, nonspecifically adsorbed K, non-exchangeable K, mineral K, and total K in contrast to NP; however, K fertilizer and straw reduce the proportion of mineral K and improve proportion of other forms of potassium in the two locating sites. Compared with the beginning of orientation, temporal variability character of soil K content and proportion showed a difference between the two soil types; furthermore, there was a decrease in the content of mineral K and total K simultaneously in the two locating sites. As a whole, the effect of K fertilizer applied to soil directly excelled to wheat straw to soil. Wheat straw to soil was an effective measure to complement potassium to increase crop yield and retard the decrease of soil K.

  20. A long-term nitrogen fertilizer gradient has little effect on soil organic matter in a high-intensity maize production system.

    Science.gov (United States)

    Brown, Kimberly H; Bach, Elizabeth M; Drijber, Rhae A; Hofmockel, Kirsten S; Jeske, Elizabeth S; Sawyer, John E; Castellano, Michael J

    2014-04-01

    Global maize production alters an enormous soil organic C (SOC) stock, ultimately affecting greenhouse gas concentrations and the capacity of agroecosystems to buffer climate variability. Inorganic N fertilizer is perhaps the most important factor affecting SOC within maize-based systems due to its effects on crop residue production and SOC mineralization. Using a continuous maize cropping system with a 13 year N fertilizer gradient (0-269 kg N ha(-1) yr(-1)) that created a large range in crop residue inputs (3.60-9.94 Mg dry matter ha(-1) yr(-1)), we provide the first agronomic assessment of long-term N fertilizer effects on SOC with direct reference to N rates that are empirically determined to be insufficient, optimum, and excessive. Across the N fertilizer gradient, SOC in physico-chemically protected pools was not affected by N fertilizer rate or residue inputs. However, unprotected particulate organic matter (POM) fractions increased with residue inputs. Although N fertilizer was negatively linearly correlated with POM C/N ratios, the slope of this relationship decreased from the least decomposed POM pools (coarse POM) to the most decomposed POM pools (fine intra-aggregate POM). Moreover, C/N ratios of protected pools did not vary across N rates, suggesting little effect of N fertilizer on soil organic matter (SOM) after decomposition of POM. Comparing a N rate within 4% of agronomic optimum (208 kg N ha(-1) yr(-1)) and an excessive N rate (269 kg N ha(-1) yr(-1)), there were no differences between SOC amount, SOM C/N ratios, or microbial biomass and composition. These data suggest that excessive N fertilizer had little effect on SOM and they complement agronomic assessments of environmental N losses, that demonstrate N2 O and NO3 emissions exponentially increase when agronomic optimum N is surpassed.

  1. Dynamics of bacterial communities in rice field soils as affected by different long-term fertilization practices.

    Science.gov (United States)

    Ahn, Jae-Hyung; Lee, Shin Ae; Kim, Jeong Myeong; Kim, Myung-Sook; Song, Jaekyeong; Weon, Hang-Yeon

    2016-11-01

    Fertilization and the response of the soil microbial community to the process significantly affect crop yield and the environment. In this study, the seasonal variation in the bacterial communities in rice field soil subjected to different fertilization treatments for more than 50 years was investigated using 16S rRNA sequencing. The simultaneous application of inorganic fertilizers and rice straw compost (CAPK) maintained the species richness of the bacterial communities at levels higher than that in the case of non-fertilization (NF) and application of inorganic fertilizers only (APK) in the initial period of rice growth. The seasonal variation in the bacterial community structure in the NF and APK plots showed cyclic behavior, suggesting that the effect of season was important; however, no such trend was observed in the CAPK plot. In the CAPK plot, the relative abundances of putative copiotrophs such as Bacteroidetes, Firmicutes, and Proteobacteria were higher and those of putative oligotrophs such as Acidobacteria and Plactomycetes were lower than those in the other plots. The relative abundances of organotrophs with respiratory metabolism, such as Actinobacteria, were lower and those of chemoautotrophs that oxidize reduced iron and sulfur compounds were higher in the CAPK plot, suggesting greater carbon storage in this plot. Increased methane emission and nitrogen deficiency, which were inferred from the higher abundances of Methylocystis and Bradyrhizobium in the CAPK plot, may be a negative effect of rice straw application; thus, a solution for these should be considered to increase the use of renewable resources in agricultural lands.

  2. Spatial variability of soil total and DTPA-extractable cadmium caused by long-term application of phosphate fertilizers, crop rotation, and soil characteristics.

    Science.gov (United States)

    Jafarnejadi, A R; Sayyad, Gh; Homaee, M; Davamei, A H

    2013-05-01

    Increasing cadmium (Cd) accumulation in agricultural soils is undesirable due to its hazardous influences on human health. Thus, having more information on spatial variability of Cd and factors effective to increase its content on the cultivated soils is very important. Phosphate fertilizers are main contamination source of cadmium (Cd) in cultivated soils. Also, crop rotation is a critical management practice which can alter soil Cd content. This study was conducted to evaluate the effects of long-term consumption of the phosphate fertilizers, crop rotations, and soil characteristics on spatial variability of two soil Cd species (i.e., total and diethylene triamine pentaacetic acid (DTPA) extractable) in agricultural soils. The study was conducted in wheat farms of Khuzestan Province, Iran. Long-term (27-year period (1980 to 2006)) data including the rate and the type of phosphate fertilizers application, the respective area, and the rotation type of different regions were used. Afterwards, soil Cd content (total or DTPA extractable) and its spatial variability in study area (400,000 ha) were determined by sampling from soils of 255 fields. The results showed that the consumption rate of di-ammonium phosphate fertilizer have been varied enormously in the period study. The application rate of phosphorus fertilizers was very high in some subregions with have extensive agricultural activities (more than 95 kg/ha). The average and maximum contents of total Cd in the study region were obtained as 1.47 and 2.19 mg/kg and DTPA-extractable Cd as 0.084 and 0.35 mg/kg, respectively. The spatial variability of Cd indicated that total and DTPA-extractable Cd contents were over 0.8 and 0.1 mg/kg in 95 and 25 % of samples, respectively. The spherical model enjoys the best fitting and lowest error rate to appraise the Cd content. Comparing the phosphate fertilizer consumption rate with spatial variability of the soil cadmium (both total and DTPA extractable) revealed the high

  3. Dynamic Relationship Between Biologically Active Soil Organic Carbon and Aggregate Stability in Long-Term Organically Fertilized Soils

    Institute of Scientific and Technical Information of China (English)

    LI Cheng-Liang; XU Jiang-Bing; HE Yuan-Qiu; LIU Yan-Li; FAN Jian-Bo

    2012-01-01

    Biologically active soil organic carbon (BASOC) is an important fraction of soil organic carbon (SOC),but our understanding of the correlation between BASOC and soil aggregate stability is limited.At an ecological experimental station (28° 04′-28° 37′ N,116°41′-117° 09′ E) in Yujiang County,Jiangxi Province,China,we analyzed the dynamic relationship between soil aggregate stability and BASOC content over time in the red soil (Udic Ferrosols) fertilized with a nitrogen-phosphorus-potassium chemical fertilizer (NPK)without manure or with NPK plus livestock manure or green manure.The dynamics of BASOC was evaluated using CO2 efflux,and soil aggregates were separated according to size using a wet-sieving technique.The soils fertilized with NPK plus livestock manure had a significantly higher content of BASOC and an improved aggregate stability compared to the soils fertilized with NPK plus green manure or NPK alone The BASOC contents in all fertilized soils decreased over time The contents of large aggregates (800-2000μm) dramatically decreased over the first 7 d of incubation,but the contents of small aggregates (< 800.μm) either remained the same or increased,depending on the incubation time and specific aggregate sizes.The aggregate stability did not differ significantly at the beginning and end of incubation,but the lowest stability inall fertilized soils occurred in the middle of the incubation,which implied that the soils had a strong resilience for aggregate stability.The change in BASOC content was only correlated with aggregate stability during the first 27 d of incubation.

  4. Evaluation of the leucine incorporation technique for detection of pollution-induced community tolerance to copper in a long-term agricultural field trial with urban waste fertilizers.

    Science.gov (United States)

    Lekfeldt, Jonas Duus Stevens; Magid, Jakob; Holm, Peter E; Nybroe, Ole; Brandt, Kristian Koefoed

    2014-11-01

    Copper (Cu) is known to accumulate in agricultural soils receiving urban waste products as fertilizers. We here report the use of the leucine incorporation technique to determine pollution-induced community tolerance (Leu-PICT) to Cu in a long-term agricultural field trial. A significantly increased bacterial community tolerance to Cu was observed for soils amended with organic waste fertilizers and was positively correlated with total soil Cu. However, metal speciation and whole-cell bacterial biosensor analysis demonstrated that the observed PICT responses could be explained entirely by Cu speciation and bioavailability artifacts during Leu-PICT detection. Hence, the agricultural application of urban wastes (sewage sludge or composted municipal waste) simulating more than 100 years of use did not result in sufficient accumulation of Cu to select for Cu resistance. Our findings also have implications for previously published PICT field studies and demonstrate that stringent PICT detection criteria are needed for field identification of specific toxicants.

  5. Long-term addition of fertilizer, labile carbon, and fungicide alters the biomass of plant functional groups in a subarctic-alpine community

    DEFF Research Database (Denmark)

    Haugwitz-Hardenberg-Reventlow, M S; Michelsen, A.

    2011-01-01

    , and the aboveground plant biomass was harvested 4 and 16 years after initiating the experiment. In addition, soil inorganic N and P concentration was analyzed the same years. Increased nutrient availability (NPK fertilizer) largely increased the biomass of graminoids and unexpectedly of bryophytes, but not of other......In subarctic ecosystems, plant growth is mostly limited by nutrient availability and harsh climate. Investigating how soil nutrient availability controls the plant community composition may therefore help to understand indirect effects of climate change. The study was conducted in a long-term field...... experiment on a subarctic-alpine fellfield dominated by woody evergreen shrubs, bryophytes, and lichens. To manipulate nutrient availability additions of NPK fertilizer, labile C, and fungicide (benomyl) were done in a fully factorial design, replicated in six blocks. The treatments were run for 10 years...

  6. Mutualistic functioning of indigenous arbuscular mycorrhizae in spring barley and winter wheat after cessation of long-term phosphate fertilization

    NARCIS (Netherlands)

    Dekkers, T.B.M.; Werff, van der P.A.

    2001-01-01

    The influence of 23 years of phosphorus (P) application at three annual rates of 0, 17.5 and 52.5 kg ha-1 on arbuscular mycorrhizal (AM) fungal colonization was studied 10 years after the fertilization treatment ended. The annual application of 52.5 kg ha-1 was about twice the annual crop P

  7. Long-Term Dynamics of Standing Crop and Species Composition after the Cessation of Fertilizer Application to Mown Grassland

    NARCIS (Netherlands)

    Olff, H.; Bakker, J.P.

    1991-01-01

    (1) Current agricultural overproduction in Western Europe has led to an increase in the area of unfertilized grassland. This paper reports an experiment where fertilizer application was stopped to try to restore former species-rich vegetation. (2) Standing crop and species composition of three diffe

  8. The long-term outcome of 946 consecutive couples visiting a fertility clinic in 2001-2003

    NARCIS (Netherlands)

    Donckers, Janneke; Evers, Johannes L. H.; Land, Jolande A.

    Objective: To describe the outcome of fertility work-up, treatment, and dropout in a cohort of subfertile couples in a well-defined area in Western Europe. Design: Prospective cohort study. Setting: Maastricht University Medical Center. Patient(s): Subfertile couples referred by their general

  9. Effects of 42-year long-term fertilizer management on soil phosphorus availability, fractionation,adsorption–desorption isotherm and plant uptake in flooded tropical rice

    Institute of Scientific and Technical Information of China (English)

    Pratap; Bhattacharyya; Amaresh; Kumar; Nayak; Mohammad; Shahid; Rahul; Tripathi; Sangita; Mohanty; Anjani; Kumar; Rajagounder; Raja; Bipin; Bihari; Panda; Banwari; Lal; Priyanka; Gautam; Chinmaya; Kumar; Swain; Koushik; Singha; Roy; Pradeep; Kumar; Dash

    2015-01-01

    Soil phosphorus(P) fractionation, adsorption, and desorption isotherm, and rice yield and P uptake were investigated in flooded tropical rice(Oryza sativa L.) following 42-year fertilizer and manure application. The treatments included low-input [unfertilized control without N, P, or K(C0N0)], farmyard manure(FYM)(C1N0), NP(C0NP), NPK(C0NPK), FYM + NP(C1NP), and high-input treatment, FYM + NPK(C1NPK). Grain yield was increased significantly by 74%over the control under the combined application of FYM + NPK. However, under low- and high-input treatments, yield as well as P uptake was maintained at constant levels for 35 years.During the same period, high yield levels and P uptake were maintained under the C0 NP, C0 NPK,and C1 NPK treatments. These are unique characteristics of a tropical flooded ecosystem, which is a self-sustaining system for rice production. The Fe–P fraction was highest compared to the Ca–P and Al–P fractions after 42 years of fertilizer application and was significantly higher under FYM + NPK treatment. The P adsorption capacity of soil was highest under the low-input treatment and lowest under long-term balanced fertilization(FYM + NPK). In contrast, P desorption capacity was highest under NPK and lowest in the control treatment. Long-term balanced fertilization in the form of FYM + NPK for 42 years lowered the bonding energy and adsorption capacity for P in soil but increased its desorption potential, increasing P availability to the plant and leading to higher P uptake and yield maintenance.

  10. [N2O and CH4 emission from Japan rice fields under different long-term fertilization patterns and its environmental impact].

    Science.gov (United States)

    Luo, Liang-guo; Kondo, Motohiko; Itoh, Sumio

    2010-12-01

    This study intended to investigate the greenhouse gases emission from Japan single cropping paddy fields after 75-year continuous application of ammonium sulfate, composted rice straw with soybean cake, and fresh clover, as well as the environmental impact of the emission. During this long period, field management remained constant in terms of rice cultivation density, irrigation, and equivalent net N fertilization. No significant differences were observed in N2O emission among the fertilization treatments, but the CH4 emission differed significantly between organic amendment and ammonium sulfate application, indicating that long-term organic fertilization didn' t increase N2O emission but promoted CH4 emission. The cumulative global warming potential (GWP) of the CH4 and NO2O from the paddy ecosystem was the greatest (310.7 g CO2e x m(-2)) under fresh clover application, followed by composted rice straw plus soybean cake addition (151 g CO2e x m(-2)), and the least (60.6 g CO2e x m(-2)) under ammonium sulfate application. This study showed that for paddy system, it was CH4 instead of N2O the major factor affecting global warming, and thereby, to control and reduce the CH4 emission from paddy system would be the core in mitigating greenhouse gases emission from paddy field. Long-term consecutive application of composted rice straw plus soybean cake could increase soil organic matter, improve soil fertility, promote rice high-yielding, and as well, mitigate CH4 emission, being the recommendable paddy rice production mode in practice.

  11. [Effects of different long-term fertilization on the activities of enzymes related to carbon, nitrogen, and phosphorus cycles in a red soil].

    Science.gov (United States)

    Fan, Miao-zhen; Yin, Chang; Fan, Fen-liang; Song, A-lin; Wang, Bo-ren; Li, Dong-chu; Liang, Yong-chao

    2015-03-01

    Using a microplate fluorimetric assay method, five fertilization treatments, i.e. no-fertilizer control (CK) , sole application of nitrogen (N), balanced application of nitrogen, phosphorus, and potassium fertilizer (NPK), application of pig manure (M), and combination of pig manure with balanced chemical fertilizer (MNPK) were selected to investigate the effects of different long-term fertilization regimes on the activity of five enzymes (β-1, 4-glucosidase, βG; cellobiohydrolase, CBH; β-1, 4-xylosidase, βX; β-1, 4-N-acetylglucosaminidase, NAG; acid phosphatase, AP) in a red soil sampled from Qiyang, Hunnan Province. The results showed that compared with CK treatment, N treatment had no impact on βG, βX, CBH, and NAG activities but reduced AP activity, while NPK, M and MNPK treatments increased the activities of all the five enzymes. Correlation analysis indicated that all the five enzyme activities were positively correlated with the content of nitrate (r=0.465-0.733) , the content of available phosphorus (r=0.612-0.947) , soil respiration (r=0.781-0.949) and crop yield (r=0.735-0.960), while βG, CBH and AP were positively correlated with pH (r= 0.707-0.809), only AP was significantly correlated with dissolvable organic carbon (r = -0.480). These results suggested that the activities of the measured enzymes could be used as indicators of red soil fertility under different fertilization regimes, but the five enzymes tested provided limited information on the degree of acidification induced by application of mineral nitrogen.

  12. Long-term CO2 fertilization increases vegetation productivity and has little effect on hydrological partitioning in tropical rainforests

    Science.gov (United States)

    Yang, Yuting; Donohue, Randall J.; McVicar, Tim R.; Roderick, Michael L.; Beck, Hylke E.

    2016-08-01

    Understanding how tropical rainforests respond to elevated atmospheric CO2 concentration (eCO2) is essential for predicting Earth's carbon, water, and energy budgets under future climate change. Here we use long-term (1982-2010) precipitation (P) and runoff (Q) measurements to infer runoff coefficient (Q/P) and evapotranspiration (E) trends across 18 unimpaired tropical rainforest catchments. We complement that analysis by using satellite observations coupled with ecosystem process modeling (using both "top-down" and "bottom-up" perspectives) to examine trends in carbon uptake and relate that to the observed changes in Q/P and E. Our results show there have been only minor changes in the satellite-observed canopy leaf area over 1982-2010, suggesting that eCO2 has not increased vegetation leaf area in tropical rainforests and therefore any plant response to eCO2 occurs at the leaf level. Meanwhile, observed Q/P and E also remained relatively constant in the 18 catchments, implying an unchanged hydrological partitioning and thus approximately conserved transpiration under eCO2. For the same period, using a top-down model based on gas exchange theory, we predict increases in plant assimilation (A) and light use efficiency (ɛ) at the leaf level under eCO2, the magnitude of which is essentially that of eCO2 (i.e., 12% over 1982-2010). Simulations from 10 state-of-the-art bottom-up ecosystem models over the same catchments also show that the direct effect of eCO2 is to mostly increase A and ɛ with little impact on E. Our findings add to the current limited pool of knowledge regarding the long-term eCO2 impacts in tropical rainforests.

  13. Changes in fertility parameters and contents of heavy metals of soddy-podzolic soils upon the long-term application of sewage sludge

    Science.gov (United States)

    Vasbieva, M. T.; Kosolapova, A. I.

    2015-05-01

    The effect of the long-term sewage sludge (SS) application on the chemical, agrophysical, and biological properties of a soddy-podzolic soil ( Umbric Albeluvisols Abruptic) was studied. Regular SS application in the course of five crop rotations (1976-2013) ensured the improvement of the soil fertility parameters, i.e., a rise in the contents of humus, available phosphorus, and exchangeable potassium; a better state of the soil adsorption complex, bulk density, and aggregation; and higher cellulolytic, nitrification, and urease activities. The efficiencies of SS and the traditional organic fertilizer (cattle manure) were compared. The effect of the long-term application of SS on the accumulation of heavy metals in the soils was also studied. It was found that the application of SS caused a rise in the bulk content of heavy metals and in the contents of their acid-extractable and mobile forms by 1.1-6.0 times. However, the maximum permissible concentrations of heavy metals in the soils were not exceeded. In the soil subjected to the application of SS for more than 25 years, the cadmium concentration somewhat exceeded the maximum permissible concentration.

  14. Effect of long-term fertilizer application in maize crop growing on chemical element leaching in Fluvisol

    Science.gov (United States)

    Simeonova, Tsetska; Stoicheva, Dimitranka; Koleva, Venelina; Sokołowska, Zofia; Hajnos, Mieczysław

    2017-04-01

    The study characterized the regime of nutrient leaching under different nitrogen and phosphorus supply of irrigated maize grown as monoculture on Fluvisol for the period 1999-2008 and additionally studied in the years 2009, 2010, and 2011. The aim of the study was to estimate the effect of longterm fertilizer application on the leaching of nutrients from the soil under maize grown as monoculture. The experiment design included four nitrogen fertilizer rates (B1-control, B5, B4, B3, B2) calculated to compensate 50, 75, 100, and 125% from the plant N uptake, respectively. The field plots were equipped with lysimeters (at 50 and 100 cm depth) for studying the relationship between the applied fertilizer rates and the nutrient concentrations in the lysimetric water. The greatest nitrogen concentration in lysimetric water was observed under variant (B3-N200 P150) throughout the study period and the highest N losses were registered (36 kg ha-1) in 2010 under the same treatment (B3). A very good correlation was found between the N rates, calcium, and magnesium losses. Lysimetric water component compensation shows that agricultural activities have only influenced the speed of weathering and had no significant effect on the rates.

  15. Microcalorimetric study of the effects of long-term fertilization on soil microbial activity in a wheat field on the Loess Plateau.

    Science.gov (United States)

    Zhang, Qi; Liu, Xiaomei; Ma, Xiaojun; Fang, Jian; Fan, Tinglu; Wu, Fasi; An, Lizhe; Feng, Huyuan

    2014-12-01

    The effects of the long-term inorganic (nitrogen, N; phosphate, P) and organic (manure, M; straw, S) fertilizers/managemenet individually and in combinations (N, NP, SNP, M, and MNP) on soil microbial activity were investigated in a wheat field on the Loess Plateau, China. Microcalorimetry was used to determine microbial activity under different treatments. Nearly 30 years of consecutive fertilization has altered the culturable population of soil bacteria and fungi, the highest ones were detected in the treatments of manure and MNP, followed by the NP and SNP treatments. The microbial growth rate constant (μ/h(-1)) was significantly greater in the MNP treatment than all the other treatments. The total heat exchange values (Q/J) were the highest in the MNP and NP treatments, which were significantly different from the N and M treatments. The peak height (P(t)/μW) were significantly higher in MNP and NP treatments than in the remaining treatments. The peak time values (t(p)/h) among the MNP, NP, SNP and M, N and CK treatments were significantly different. In general, comparing with control, soil microbial activity was much higher in MNP, NP and SNP treatments, all including the phosphate fertilizer. Our results showed that the application of inorganic fertilizer and organic manure have positive effects on multiple soil chemical parameters, soil microorganism abundance and activity, and hence crop yield.

  16. [Influences of long-term application of organic and inorganic fertilizers on the composition and abundance of nirS-type denitrifiers in black soil].

    Science.gov (United States)

    Yin, Chang; Fan, Fen-Liang; Li, Zhao-Jun; Song, A-Lin; Zhu, Ping; Peng, Chang; Liang, Yong-Chao

    2012-11-01

    The objectives of this study were to explore the effects of long-term organic and inorganic fertilizations on the composition and abundance of nirS-type denitrifiers in black soil. Soil samples were collected from 4 treatments (i. e. no fertilizer treatment, CK; organic manure treatment, OM; chemical fertilizer treatment (NPK) and combination of organic and chemical fertilizers treatment (MNPK)) in Gongzhuling Long-term Fertilization Experiment Station. Composition and abundance of nirS-type denitrifiers were analyzed with terminal restriction fragment length polymorphism (T-RFLP) and real-time quantitative PCR (Q-PCR), respectively. Denitrification enzyme activity (DEA) and soil properties were also measured. Application of organic fertilizers (OM and MNPK) significantly increased the DEAs of black soil, with the DEAs in OM and MNPK being 5.92 and 6.03 times higher than that in CK treatment, respectively, whereas there was no significant difference between NPK and CK. OM and MNPK treatments increased the abundances of nirS-type denitrifiers by 2.73 and 3.83 times relative to that of CK treatment, respectively. The abundance of nirS-type denitrifiers in NPK treatment was not significantly different from that of CK. The T-RFLP analysis of nirS genes showed significant differences in community composition between organic and inorganic treatments, with the emergence of a 79 bp T-RF, a significant decrease in relative abundance of the 84 bp T-RF and a loss of the 99 bp T-RF in all organic treatments. Phylogenetic analysis indicated that the airS-type denitrifiers in the black soil were mainly composed of alpha, beta and gamma-Proteobacteria. The 79 bp-type denitrifiers inhabiting exclusively in organic treatments (OM and MNPK) were affiliated to Pseudomonadaceae in gamma-Proteobacteria and Burkholderiales in beta-Proteobacteria. The 84 bp-types were related to Burkholderiales and Rhodocyclales. Correlation analysis indicated that pH, concentrations of total nitrogen

  17. Organic and mineral fertilization, respectively, increase and decrease the development of external mycelium of arbuscular mycorrhizal fungi in a long-term field experiment.

    Science.gov (United States)

    Gryndler, M; Larsen, J; Hrselová, H; Rezácová, V; Gryndlerová, H; Kubát, J

    2006-05-01

    Effects of long-term mineral fertilization and manuring on the biomass of arbuscular mycorrhizal fungi (AMF) were studied in a field experiment. Mineral fertilization reduced the growth of AMF, as estimated using both measurements of hyphal length and the signature fatty acid 16:1omega5, whereas manuring alone increased the growth of AMF. The results of AMF root colonization followed the same pattern as AMF hyphal length in soil samples, but not AMF spore densities, which increased with increasing mineral and organic fertilization. AMF spore counts and concentration of 16:1omega5 in soil did not correlate positively, suggesting that a significant portion of spores found in soil samples was dead. AMF hyphal length was not correlated with whole cell fatty acid (WCFA) 18:2omega6,9 levels, a biomarker of saprotrophic fungi, indicating that visual measurements of the AMF mycelium were not distorted by erroneous involvement of hyphae of saprotrophs. Our observations indicate that the measurement of WCFAs in soil is a useful research tool for providing information in the characterization of soil microflora.

  18. Long-term use of biosolids as organic fertilizers in agricultural soils: potentially toxic elements occurrence and mobility.

    Science.gov (United States)

    Marguí, E; Iglesias, M; Camps, F; Sala, L; Hidalgo, M

    2016-03-01

    The presence of potentially toxic elements (PTEs) may hinder a more widespread application of biosolids in agriculture. At present, the European Directive 86/278/CEE limit the total concentrations of seven metals (Cu, Cr, Ni, Pb, Zn, Cd and Hg) in agricultural soils and in sewage sludges used as fertilizers but it has not taken into consideration the potential impacts of other emerging micropollutants that may be present in the biosolids as well as their mobility. The aim of this study was to evaluate the accumulation and mobility of 13 elements (including regulated metals and other inorganic species) in agricultural soils repeatedly amended with biosolids for 15 years. Firstly, three digestions programs using different acid mixtures were tested to evaluate the most accurate and efficient method for analysis of soil and sludge. Results demonstrated that sewage sludge application increased concentrations of Pb and Hg in soil, but values did not exceed the quality standard established by legislation. In addition, other elements (As, Co, Sb, Ag, Se and Mn) that at present are not regulated by the Spanish and European directives were identified in the sewage sludge, and significant differences were found between Ag content in soils amended with biosolids in comparison with control soils. This fact can be related to the increasing use of silver nanoparticles in consumer products due to their antibacterial properties. Results from the leaching tests show up that, in general, the mobility degree for both regulated and non-regulated elements in soils amended with biosolids was quite low (<10 %).

  19. Dump stability and soil fertility of a coal mine spoil in Indian dry tropical environment: a long-term study.

    Science.gov (United States)

    Tripathi, Nimisha; Singh, Raj Shekhar; Chaulya, Swadesh K

    2012-10-01

    Plant available nitrogen, belowground (root) biomass, soil nitrogen (N) mineralization and microbial biomass N (MBN) were studied for 12 years at the interval of 2 years (0, 2, 4, 6, 8, 10 and 12 years) and mine dump stability at the intervals of 6 years (0, 6 and 12 years) after re-vegetation on coal mine spoil site. Plant available nitrogen in revegetated mine spoil ranged from 4.51 to 6.59 μg g(-1), net N-mineralization from 1.87 to 13.85 μg g(-1) month(-1), MBN from 10 to 22.63 μg g(-1), and root biomass from 28 to 566 g(-2). Mining activity has caused a change in soil characteristics including plant available nutrients like nitrate-N, ammonium-N and phosphate-P by 70, 67, and 76 %, respectively, N-mineralization by 93 %, root biomass values by 97 % and MBN values by 91 % compared to forest ecosystems. Revegetation of mine spoil produced increase in root biomass values by 1.3, 7.6 and 17.2 times, mineral N values by 1.22, 1.43 and 1.79 times, N-mineralization values by 1.8, 5.2 and 12.6 times and MBN values by 1.6, 2.0, and 3.4 times in 2, 6 and 12 years, respectively. Below ground biomass was highly co-related with microbial biomass and plant available nutrients. N-mineralization, plant available nutrients and the clay content were positively correlated with age of revegetation (P soil fertility status in mine spoil, where plant biomass and microbial biomass provide major contributions in ecological redevelopment of the mine spoil.

  20. Archaeal dominated ammonia-oxidizing communities in Icelandic grassland soils are moderately affected by long-term N fertilization and geothermal heating

    Directory of Open Access Journals (Sweden)

    Anne eDaebeler

    2012-10-01

    Full Text Available The contribution of ammonia-oxidizing bacteria and archaea (AOB and AOA, respectively to the net oxidation of ammonia varies greatly between terrestrial environments. To better understand, predict and possibly manage terrestrial nitrogen turnover, we need to develop a conceptual understanding of ammonia oxidation as a function of environmental conditions including the ecophysiology of the associated organisms. We examined the discrete and combined effects of mineral nitrogen deposition and geothermal heating on ammonia-oxidizing communities by sampling soils from a long-term fertilisation site along a temperature gradient in Icelandic grasslands. Microarray, clone library and quantitative PCR analyses of the ammonia monooxygenase subunit A (amoA gene accompanied by physico-chemical measurements of the soil properties were conducted. In contrast to most other terrestrial environments, the ammonia-oxidizing communities consisted almost exclusively of archaea. Their bacterial counterparts proved to be undetectable by quantitative PCR suggesting AOB are only of minor relevance for ammonia oxidation in these soils. Our results show that fertilization and local, geothermal warming affected detectable ammonia-oxidizing communities, but not soil chemistry: only a subset of the detected AOA phylotypes was present in higher temperature soils and AOA abundance was increased in the fertilized soils, while the measured soil physico-chemical properties remained unchanged. Differences in distribution and structure of AOA communities were best explained by soil pH and clay content irrespective of temperature or fertilizer treatment in these grassland soils, suggesting that these factors have a greater potential for ecological niche-differentiation of AOA in soil than temperature and N fertilization.

  1. China's far below replacement fertility and its long-term impact: Comments on the preliminary results of the 2010 census

    Directory of Open Access Journals (Sweden)

    Zhongwei Zhao

    2011-12-01

    Full Text Available The Chinese government conducted its sixth national census in 2010 and released its major results in April 2011. According to the National Bureau of Statistics the quality of the census was very high. Although the currently released census results consist of limited statistics only, they shed new light on China's recent fertility levels, which have been debated among scholars and policy makers for more than a decade. The 2010 census results, however, also show considerable inconsistencies with those published by the United Nations Population Division recently. This paper will, on the basis of newly published census results and other available evidence, further examine China's recent fertility decline and its impact on the country's long-term development. It will also comment on the major discrepancies between the results of Chinese government recent population projection, the United Nations' World Population Prospects, the 2010 Revision and China's 2010 census, and investigate the underlying causes that have led to these differences.

  2. THE INFLUENCE OF LONG-TERM APPLICATION OF FERTILIZERS ON THE SUGARINESS OF BEET IN THE CONDITIONS OF INSUFFICIENT WATERING OF THE WESTERN CISCAUCASIA

    Directory of Open Access Journals (Sweden)

    Bershatskaya S. I.

    2016-03-01

    Full Text Available This article presents the experimental material obtained from long-term stationary experiment of GNU "Severokubanskaya agricultural experimental station" in P.P. Lukyanenko Krasnodar Agricultural Research Institute. Stationary experience was founded in 1978. It had two ten-course crop rotations and combined graingrass tilled. The ordinary black soil, low-humic, heavy loamy in mechanical composition. The capacity of humus horizon is 113-116 cm with a total content of humus on the date of the experience beginning is 3.88%. Arable (0-30cm layer was characterized by the following parameters: total nitrogen content - 0.22-0.24, mineral -10,0-10,5mg / kg of soil, total phosphorus-0,16- 0,19%, labile phosphorus - 12,2-12,9mg / kg soil total potassium -1,7-2,0%, exchange potassium- 386mg / kg soil. The degree of saturation of bases is 80-90%. The amount of absorbed bases is 30-40 m ekvg/ 100 g of soil. The reaction of the soil solution is weakly alkaline (PH water 8.0-8.2. The predecessor is winter wheat. General Agrotechnics is recommended for a given soil and climate of region. Solid mineral fertilizer were applied as mineral fertilizers in combination with organic fertilizer in the form of half-decomposed cattle manure. According to agro-climatic zonation the northern zone of the Krasnodar region, where the research was conducted, is related to the zone of insufficient watering with hydrothermal coefficient 0.7-0.9 with an annual rainfall of 350.5 to 899.8 mm. During the autumn and winter period, which determines the accumulation of water in the soil, from 150.3 to 426.8 mm of rain falls or 30,4-68,9% of the annual amount. During the vegetation of sugar beet from germination to harvest -112,0- 588,9mm of rain falls, with an average daily temperature of the air 16,5-20,000С, including the period of the greatest growth of roots and accumulation of sugar from 3.2 to 557.1 of rain falls with air temperature 19,5-28,800С. Hydrothermal index is 0

  3. 长期间作牧草对椰园土壤肥力的影响%Effects of Long-term Intercropping Pastures on Coconut Soil Fertility

    Institute of Scientific and Technical Information of China (English)

    王萍; 刘立云; 杨伟波; 陈思婷; 唐龙祥; 王东劲; 周汉林; 郇树乾

    2011-01-01

    After long-term intercropping pastures in young coconut grove for 10 years, the soil pH of 0 -20 cm decreased 0.92 unit, the 20 - 40 cm decreased 0.75 unit, and in old coconut grove the soil pH of 0 - 20 cm decreased 0.82 unit, the 20 - 40 cm decreased 1.04 unit; after long-term intercropping pastures in young coconut grove for 10 years, the soil water content was lower than before, but higher than before , in old coconut grove the soil water content decreased above half than before and was lower compared with the young coconut grove; after long-term intercropping pastures in young coconut grove for 10 years, the soil organic matter of 0 -20 cm was higher than before, but the 20 -40 cm was lower, and in old coconut grove there were all lower; after long-term intercropping pastures in young coconut grove for 10 years, the soil total nitrogen content was a little lower than before, but in old coconut grove it decreased above half than before, but was higher compared with the young coconut grove. These results suggesed that long-term intercropping pastures in coconut grove, there must be applying fertilizer properly, and combining with proper lime or adopting legume-graminaceae rotation or legume-non graminaceae rotation.%幼龄椰园长期间作牧草,10年后0~20 cm层下降0.92个pH单位,20~40cm层下降0.75个单位,而成龄椰园0~20 cm层下降0.82个单位,20~40 cm层下降1.04个单位;幼龄椰园间作牧草,10年后土壤含水量有所下降,但仍比间作前高,而成龄椰园土壤含水量下降了一半以上,而且比幼龄椰园低;幼龄椰园间作牧草,10年后0~20 cm土层有机质含量比间作前有所上升,但20~40cm以下则低于间作前,成龄椰园均比间作前明显降低;幼龄椰园间作牧草,10年后土壤全氮含量略微降低,而成龄椰园下降了一半以上,但目前成龄椰园的土壤全氮含量比幼龄椰园的略高.建议椰园实行长期牧草间作,每年必须追施足够的肥料,并

  4. Long-Term Effects of Manure and Inorganic Fertilizers on Yield and Soil Fertility for a Winter Wheat-Maize System in Jiangsu, China

    Institute of Scientific and Technical Information of China (English)

    JIANG Dong; H. HENGSDIJK; DAI Ting-Bo; W. de BOER; JING Qi; CAO Wei-Xing

    2006-01-01

    Winter wheat-maize rotations are dominant cropping systems on the North China Plain, where recently the use of organic manure with grain crops has almost disappeared. This could reduce soil fertility and crop productivity in the long run. A 20-year field experiment was conducted to 1) assess the effect of inorganic and organic nutrient sources on yield and yield trends of both winter wheat and maize, 2) monitor the changes in soil organic matter content under continuous wheat-maize cropping with different soil fertility management schemes, and 3) identify reasons for yield trends observed in Xuzhou City, Jiangsu Province, over a 20-year period. There were eight treatments applied to both wheat and maize seasons: a control treatment (C); three inorganic fertilizers, that is, nitrogen (N), nitrogen and phosphorus (NP), and nitrogen, phosphorus and potassium (NPK); and addition of farmyard manure (FYM) to these four treatments, that is,M, MN, MNP, and MNPK. At the end of the experiment the MN, MNP, and MNPK treatments had the highest yields,about 7 t wheat ha-1 and 7.5 t maize ha-1, with each about i t ha-1 more than the NPK treatments. Over 20 years with FYM soil organic matter increased by 80% compared to only 10% with NPK, which explained yield increases. However,from an environmental and agronomic perspective, manure application was not a superior strategy to NPK fertilizers.If manure was to be applied, though, it would be best applied to the wheat crop, which showed a better response than maize.

  5. 长期施肥对薄层黑土酶活性及土壤肥力的影响%Effect of long-term fertilization on enzyme activities and soit fertility in the black thin-layer soil

    Institute of Scientific and Technical Information of China (English)

    焦晓光; 隋跃宇; 魏丹

    2011-01-01

    Soil enzyme activities and soil fertility were studied to explore the long-term fertilization on soil enzyme activities and its relationship with soil fertility on the basis of 29-years long-term site-specific experiment with different fertilization methods. The results showed that combined application of chemical fertilizers and organic manure could significantly increase the soil organic matter, total nitrogen, total phosphorus, alkali-soluble nitrogen, available phosphorus content and enhance the soil urease, phosphatase, invertase, catalase, dehydrogenase activity. The results of correlation analysis showed that soil urease, phosphatase, invertase catalase and dehydrogenase activity positively corrected with organic matter, total nitrogen, total phosphorus and alkali-soluble nitrogen significantly, and the integrated activities of soil urease, phosphatase, invertase, catalase dehydrogenase activity could reflect the changing trend of black thin-layer soil quality in the farmland after long-term fertilization.%利用29年的长期定位试验,对不同的施肥方式下薄层黑土酶活性及肥力进行了研究,探讨长期施肥对土壤酶活性及与土壤肥力的影响.结果表明,化肥与有机肥配合施用能明显提高土壤有机质、全氮、全磷、碱解氮、有效磷含量,增强土壤脲酶、磷酸酶、转化酶、过氧化氢酶、脱氢酶活性.相关分析结果显示,土壤脲酶、磷酸酶、转化酶、过氧化氢酶、脱氢酶活性与有机质、全氮、全磷、有效磷、碱解氮呈显著正相关.土壤脲酶、磷酸酶、转化酶、过氧化氢酶、脱氢酶综合活性可以反映长期施肥后薄层黑土质量的变化趋势.

  6. [Effects of long-term fertilization on reddish paddy soil quality and its evaluation in a typical double-rice cropping region of China].

    Science.gov (United States)

    Nie, Jun; Yang, Zeng-Ping; Zheng, Sheng-Xian; Liao, Yu-Lin; Xie, Jian; Xiang, Yan-Wen

    2010-06-01

    In order to quantify the effects of 27 years application of chemical fertilizers, pig manure, and rice straw on the reddish paddy soil quality in double rice cropping region, the indices of soil bulk density, porosity, maximum water holding capacity, normalized mean weight diameter, pH, cation exchange capacity, available nutrients, organic matter, microbial biomass C, enzyme activities, and rice yield were selected as the evaluation indicators, and classified into four functional groups, i. e., resistance to physical degradation, plant nutrients supply and storage, resistance to biochemical degradation, and sustaining of crop productivity. The soil quality index (SQI) was calculated based on the four functional groups. The results showed that the SQI ranged from 0.544 in treatment CK to 0.729 in treatment NPK plus rice straw. Treatments PK, NP, and NK induced soil degradation, compared to treatment NPK. The deficiencies of soil P and K were the main limiting factors for the double rice productivity in reddish paddy soil area. Even though 30 t x hm(-2) x a(-1) of pig manure and 4.2 t x hm(-2) x a(-1) of rice straw were applied, the soil P and K were still not adequate for the requirement of rice growth. There was no obvious effect of long-term application of lime on the reddish paddy soil quality. The combined application of NPK with organic manure was an important and effective measure in improving soil quality in double rice cropping regions of Southern China.

  7. Effects of long-term fertilization on soil fungi%长期施肥对农田土壤真菌的影响

    Institute of Scientific and Technical Information of China (English)

    王轶; 李季; 曹志平; 杨合法

    2014-01-01

    不合理施肥所引发的土壤环境问题逐渐成为制约我国农业可持续发展的重要因素之一,而土壤真菌作为一类重要的土壤微生物,研究施肥措施对真菌群落的影响对促进农业生产具有重要意义。本研究以有20年历史的长期定位试验田为研究对象,利用末端限制性片段长度多态性分析技术,对长期定位施肥农田生态系统中不同施肥方式对土壤真菌群落的影响以及时间变化规律进行了系统研究。长期施肥定位试验包括 EM堆肥(EM)、传统堆肥(OF)、化肥(CF)和不施肥(CK)处理。主要研究结果如下:在0~20 cm土层,施肥处理对土壤真菌多样性有显著影响, Shannon-Weiner多样性指数为2.64~3.53, Simpson集中性指数为0.03~0.08; EM和OF处理的Shannon-Weiner多样性指数均显著高于CF和CK;在3月、6月和10月, EM和OF处理与CF和CK处理相比,有较高的真菌多样性;Simpson集中性指数最高的是3月的CK处理,最低的是10月的EM和OF 处理。冗余分析结果表明,土壤 pH、有机质、总氮、有效磷和有效钾等对真菌影响显著。因此,长期施用有机肥与化肥相比可以提高土壤真菌多样性,改变其群落结构;与化肥处理相比,施用EM堆肥,不仅可以保持土壤可持续利用性,同时改善0~20 cm土层土壤真菌的生存环境;3种施肥处理对土壤真菌群落结构影响程度由强到弱:EM>OF>CF。%Fungi are critical for the decomposition of terrestrial organic matter and subsequent global carbon cycle. High microbial diversity is essential for efficient nutrient recycling in soils. To investigate the impacts of different application modes of fertilizers on fungal communities, a long-term fertilization experiment (of over 20 years of continuous fertilizer treatments) was conducted in North China. Soil samples were collected from 4 treatments: effective microorganisms compost (EM), traditional compost (OF), chemical fertilizer (CF

  8. 长期施肥对农田土壤氮素关键转化过程的影响%Effects of Long-term Fertilization on Key Processes of Soil Nitrogen Cycling in Agricultural Soil:A Review

    Institute of Scientific and Technical Information of China (English)

    王敬; 程谊; 蔡祖聪; 张金波

    2016-01-01

    fertilizer in the future. Therefore,optimal N fertilizer management strategies synchronizing N supply with crop demand should be developed to maintain crop yield and economic profit while minimizing negative environmental impact. Organic fertilizer as substitute for mineral N fertilizer has been advocated and practiced to increase soil carbon(C)sequestration and improve soil fertility. It has also been suggested that application of organic fertilizers,either alone or in combination with mineral N fertilizers,is effective in mitigating N-related pollution,improving soil fertility,and increasing crop yield. At present,how to fertilize rationally,improve crop yields,build up soil fertility and meanwhile maintain a sound ecological environment is one of the major challenges to agricultural research. Which step of N transformation in the soil would long-term application of organic manure affect thus influencing N supplying capacity and N retaining mechanism of the soil? What is the mechanism behind long-term application of organic manure decreasing N-related pollution and the increasing crop yield? This review elaborated effects of long-term fertilization on key processes of soil nitrogen cycling in agricultural soil in expectation to provide some theoretical basis for rationalization of long-term fertilization and improvement of N fertilizer utilization rate. The review proceeded from the angle of primary N transformation rate of the processes of soil nitrogen cycling to discuss effects of fertilization(mineral or organic fertilizers)on key processes of the soil nitrogen cycling. Soil N mineralization and assimilation are two crucial links in the cycling and factors that determine soil N supplying capacity. Long term application of nitrogen fertilizers could increase soil organic N and C contents and provide crops with available N slowly through mineralization of soil organic N and subsequent nitrification. Large volumes of long-term fertilization experiments demonstrate that

  9. Exploring the immediate and long-term impact on bacterial communities in soil amended with animal and urban organic waste fertilizers using pyrosequencing and screening for horizontal transfer of antibiotic resistance

    DEFF Research Database (Denmark)

    Riber, Leise; Poulsen, Pernille H. B.; Al-Soud, Waleed A.

    2014-01-01

    We investigated immediate and long-term effects on bacterial populations of soil amended with cattle manure, sewage sludge or municipal solid waste compost in an ongoing agricultural field trial. Soils were sampled in weeks 0, 3, 9 and 29 after fertilizer application. Pseudomonas isolates were...... time. Seasonal changes seemed to prevail with decreasing bacterial richness in week 9 followed by a significant increase in week 29 (springtime). The Pseudomonas population richness seemed temporarily affected by fertilizer treatments, especially in sludge- and compost-amended soils. To explain...

  10. Changes in Soil Carbon and Enzyme Activity As a Result of Different Long-Term Fertilization Regimes in a Greenhouse Field: e0118371

    National Research Council Canada - National Science Library

    Lili Zhang; Wei Chen; Martin Burger; Lijie Yang; Ping Gong; Zhijie Wu

    2015-01-01

      In order to discover the advantages and disadvantages of different fertilization regimes and identify the best management practice of fertilization in greenhouse fields, soil enzyme activities involved in carbon (C...

  11. Effects of long-term fertilizer on soil fertility and soil enzyme activities in upland red soils%长期施肥对旱地红壤肥力和酶活性的影响

    Institute of Scientific and Technical Information of China (English)

    邵兴华; 徐金仁; 张建忠; 李海峰; 周同林; 张辉

    2011-01-01

    In order to understand the relation between soil enzyme activity and soil chemical propertities in upland red soil under different fertilizer treatments, we conducted a study to determine the effects of pig manure, inorganic fertiliser and combination of pig manure and inorganic NPK on soil chemical and biological properties in a more than 30 a long-term fertilization experiment. The treatments as the following: no fertilization(CK), N, NP, NPK, double NPK, pig manure, NPK+pig manure. The results showed, the total N content had no significant difference between different treatments. The only applied N could significantly improve available N in soil. Soil pH, organic matter, total P and available P in manure fertilization treatments ( NPK+pig manure and pig manure) all increased significantly compared with no fertilization (CK) and mineral fertilization treatmets (N, NP, NPK and double NPK). Except for the highest urease activity was double NPK treatment, the soil invertase, dehydrognease, catalase and acid phosphatase activities were all significantly higher than those in other fertilization treatments. Acid phosphatase, catalase, dehydrognease and urease activities were significant and dramatically significant positively correlated with total N, organic matter and available N. So, manure application or co-application of manure and mineral fertilizers not only increased the soil fertility, but also enhanced significantly soil enzymes activities, thus could improve red soil sustainable productivity.%为了明确不同施肥种类对旱地红壤肥力与酶活性的影响,以30年(1981年至今)长期定位试验地为基础,研究不同施肥处理(CK,N,NP,NPK,2倍NPK,猪粪,NPK+猪粪)旱地红壤玉米田耕层(0~20 cm)土壤酶活性与养分的变化趋势及其相关性.结果表明:1)全N含量各处理间差异不显著,单施N肥显著增加土壤速效N,施有机肥处理(NPK+猪粪,猪粪)土壤的pH值、有机质、全P、速效P均显著增加;2)

  12. Long-term effects of mineral and organic fertilization on soil organic matter fractions and sorghum yield under Sudano-Sahelian conditions

    NARCIS (Netherlands)

    Mando, A.; Bonzi, M.; Wopereis, M.C.S.; Lompo, F.; Stroosnijder, L.

    2005-01-01

    Knowledge of changes in soil organic matter (SOM) fractions resulting from agricultural practice is important for decision-making at farm level because of the contrasting effects of different SOM fractions on soils. A long-term trial sited under Sudano-Sahelian conditions was used to assess the effe

  13. Extra soil fertilization of mother plants increases botanical seed yield but not long-term germination in wild Solanum (potato) species

    Science.gov (United States)

    Potato has about 100 wild species relatives that are multiplied in the form of botanical seed populations by genebanks, and distributed for use in research and breeding, so factors that affect long term seed germination are of interest. In 1987 the US Potato Genebank conducted routine seed multiplic...

  14. Impact of Long-Term Fertilization on Community Structure of Ammonia Oxidizing and Denitrifying Bacteria Based on amoA and nirK Genes in a Rice Paddy from Tai Lake Region, China

    Institute of Scientific and Technical Information of China (English)

    JIN Zhen-jiang; LI Lian-qing; LIU Xiao-yu; PAN Gen-xing; Qaiser Hussein; LIU Yong-zhuo

    2014-01-01

    Ammonia oxidizing (AOB) and denitrifying bacteria (DNB) play an important role in soil nitrogen transformation in natural and agricultural ecosystems. Effects of long-term fertilization on abundance and community composition of AOB and DNB were studied with targeting ammonia monooxygenase (amoA) and nitrite reductase (nirK) genes using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and real-time PCR, respectively. A ifeld trial with different fertilization treatments in a rice paddy from Tai Lake region, centre East China was used in this study, including no fertilizer application (NF), balanced chemical fertilizers (CF), combined organic/inorganic fertilizer of balanced chemical fertilizers plus pig manure (CFM), and plus rice straw return (CFS). The abundances and richnesses of amoA and nirK were increased in CF, CFM and CFS compared to NF. Principle component analysis of DGGE proifles showed signiifcant difference in nirK and amoA genes composition between organic amended (CFS and CFM) and the non-organic amended (CF and NF) plots. Number of amoA copies was signiifcantly positively correlated with normalized soil nutrient richness (NSNR) of soil organic carbon (SOC) and total nitrogen (T-N), and that of nirK copies was with NSNR of SOC, T-N plus total phosphorus. Moreover, nitriifcation potential showed a positive correlation with SOC content, while a signiifcantly lower denitriifcation potential was found under CFM compared to under CFS. Therefore, SOC accumulation accompanied with soil nutrient richness under long-term balanced and organic/inorganic combined fertilization promoted abundance and diversity of AOB and DNB in the rice paddy.

  15. Effects of Long-term Located Fertilization on the Physiochemical Properties of Non-calcareous Alluvial Soil%长期定位施肥对无石灰性潮土理化性质的影响

    Institute of Scientific and Technical Information of China (English)

    赵秀芬; 李俊良

    2009-01-01

    [目的]为改善土壤理化性质和促进农业可持续发展提供理论依据.[方法]通过田间试验研究长期定位不同施肥对无石灰性潮土理化性质的影响.[结果]单施有机肥处理的土壤含水量最高,CK的土壤含水量最低.施用有机肥处理的土壤容重较小,CK和无机肥处理的土壤容重较大.施用有机肥处理的土壤孔隙度显著高于不施有机肥处理和CK.施用有机肥、化肥处理和CK的土壤有机质含量分别约为原始土样的7.5、2.8和2.3倍.施用有机肥处理的土壤pH值提高了0.62,施用无机肥处理的土壤pH值降低.长期定位不同施肥对土壤速效养分氮磷钾含量的影响为:有机-无机肥料配施>单施大量有机肥>无机肥配施>单施氮肥>不施肥.[结论]有机-无机肥料配施能有效改善无石灰性潮土的理化性质.%[Objective]The purpose of the research was to supply theoretical basis for improving the physiochemical properties of soil and promoting agricultural sustainable development. [Method]The effects of applying different fertilizers in long-term located fertilization on the physiochemical properties of non-calcareous alluvial soil were researched through field experiment. [Result]The soil water content in the treatment with organic fertilizer only was highest and that in CK was lowest. The soil buil density in the treatment with organic fertilizer was smaller and that in CK and the treatment with inorganic fertilizer were bigger. The soil porosity in the treatment with organic fertilizer was significantly higher than that in the treatment without organic fertilizer and CK. The soil organic matter contents in the treatments with organic fertilizer, chemical fertilizer and CK were about 7.5, 2.8 and 2.3 times of that in the original soil samples resp. The soil pH value in the treatment with organic fertilizer was enhanced by 0.62 and that in the treatment with inorganic fertilizer was decreased. The effects of

  16. Nutrient limitation restricts growth and reproductive output in a tropical montane cloud forest bromeliad: findings from a long-term forest fertilization experiment.

    Science.gov (United States)

    Lasso, Eloisa; Ackerman, James D

    2013-01-01

    From studies in seasonal lowland tropical forests, bromeliad epiphytes appear to be limited mainly by water, and to a lesser extent by nutrient supply, especially phosphorous. Less is understood about the mineral nutrition of tropical montane cloud forest (TMCF) epiphytes, even though their highest diversity is in this habitat. Nutrient limitation is known to be a key factor restricting forest productivity in TMCF, and if epiphytes are nutritionally linked to their host trees, as has been suggested, we would expect that they are also nutrient limited. We studied the effect of a higher nutrient input on reproduction and growth of the tank bromeliad Werauhia sintenisii in experimental plots located in a TMCF in Puerto Rico, where all macro- and micronutrients had been added quarterly starting in 1989 and continuing throughout the duration of this study. We found that bromeliads growing in fertilized plots were receiving litterfall with higher concentrations of N, P, and Zn and had higher concentrations of P, Zn, Fe, Al, and Na in their vegetative body. The N:P ratios found (fertilized = 27.5 and non-fertilized = 33.8) suggest that W. sintenisii may also be phosphorous limited as are lowland epiphytes. Fertilized plants had slightly longer inflorescences, and more flowers per inflorescence, than non-fertilized plants, but their flowers produced nectar in similar concentrations and quantities. Fertilized plants produced more seeds per fruit and per plant. Frequency of flowering in two consecutive years was higher for fertilized plants than for controls, suggesting that fertilized plants overcome the cost of reproduction more readily than non-fertilized plants. These results provide evidence that TMCF epiphytic bromeliads are nutrient limited like their lowland counterparts.

  17. Long-term collections

    CERN Multimedia

    Collectes à long terme

    2007-01-01

    The Committee of the Long Term Collections (CLT) asks for your attention for the following message from a young Peruvian scientist, following the earthquake which devastated part of her country a month ago.

  18. Paddy Soil Stability and Mechanical Properties as Affected by Long-Term Application of Chemical Fertilizer and Animal Manure in Subtropical China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Wet stability, penetration resistance (PR), and tensile strength (TS) of paddy soils under a fertilization experiment for 22 years were determined to elucidate the function of soil organic matter in paddy soil stabilization. The treatments included no fertilization (CK), normal chemical fertilization (NPK), double the NPK application rates (2NPK), and NPK mixed with organic manure (NPK+OM). Compared with CK, fertilization increased soil organic carbon (SOC) and soil porosity. The results of soil aggregate fragmentation degree (SAFD) showed that fast wetting by water was the key fragmentation mechanism. Among the treatments, the NPK+OM treatment had the largest size of water-stable aggregates and greatest normal mean weight diameter (NMWD) (P ≤ 0.05), but the lowest PR and TS in both cultivated horizon (Ap) and plow pan. The CK and 2NPK treatments were measured with PR > 2.0 MPa and friability index < 0.20,respectively, in the Ap horizon, suggesting that the soils was mechanically unfavourable to root growth and tillage. In the plow pan, the fertilization treatments had greater TS and PR than in CK. TS and PR of the tested soil aggregates were negatively correlated to SOC content and soil porosity. This study suggested that chemical fertilization could cause deterioration of mechanical properties while application of organic manure could improve soil stability and mechanical properties.

  19. Characteristics of crop yield and nutrient balance under different long-term fertilization practices in black soil%长期不同施肥措施下黑土作物产量与养分平衡特征

    Institute of Scientific and Technical Information of China (English)

    郝小雨; 周宝库; 马星竹; 高中超

    2015-01-01

    With a cropping area of 7.0 million hm2, the black soil (Typic hapludoll) region of Northeast China plays a crucial role in food security to the regional and whole country. In fact, the application of chemical fertilizer is an effective and fast way to increase crop production in a relatively short time. Recently, organic manure application has almost disappeared because its application in cropping system is both labor-demanding and uneconomical. However, there is limited information on crop yields under long-term fertilization of organic and inorganic fertilizers in this rotation system. Nutrient input/output and balance in farmland is critical for nutrient management, scientific distribution and application of fertilizer resources, and improving nutrient use efficiency, etc. The study was conducted to reveal the difference of grain yield and nutrient balance based on the average crop yields, the variation trends of crop yields and apparent balance of soil nutrients under different long-term fertilization conditions in black soil, and to provide scientific references for establishing effective long-term fertilization mode and promoting the sustainable development of crop production. A long-term experiment with various fertilizations was carried out during 1979-2014 in a rotation system with wheat (Triticum Aestivium L.)-soybean (Glycine max Merr.)-maize (Zea mays L.) in black soil area of Northeast China. The experiment consisted of 5 treatments:non-fertilization (CK), conventional chemical fertilizer (wheat:N 150kg/hm2, P2O5 75 kg/hm2, soybean:N 75kg/hm2, P2O5 150 kg/hm2, corn:N 150kg/hm2, P2O5 75 kg/hm2, K2O 75kg/hm2, NPK), conventional horse manure (18 600 kg/hm2 , M), conventional horse manure plus chemical fertilizer(the amount of chemical fertilizer was same as NPK, and the amount of horse manure was same as M), and 200% of the MNP (horse manure and chemical fertilizer, the amount was 2 times that of MNP, M2N2P2,). The results showed that: 1) Compared with

  20. Proton accumulation accelerated by heavy chemical nitrogen fertilization and its long-term impact on acidifying rate in a typical arable soil in the Huang-Huai-Hai Plain

    Institute of Scientific and Technical Information of China (English)

    HUANG Ping; ZHANG Jia-bao; XIN Xiu-li; ZHU An-ning; ZHANG Cong-zhi; MA Dong-hao; ZHU Qiang-gen; YANG Shan; WU Sheng-jun

    2015-01-01

    Cropland productivity has been signiifcantly impacted by soil acidiifcation resulted from nitrogen (N) fertilization, especialy as a result of excess ammoniacal N input. With decades’ intensive agricultural cultivation and heavy chemical N input in the Huang-Huai-Hai Plain, the impact extent of induced proton input on soil pH in the long term was not yet clear. In this study, acidiifcation rates of different soil layers in the soil proifle (0–120 cm) were calculated by pH buffer capacity (pHBC) and net input of protons due to chemical N incorporation. Topsoil (0–20 cm) pH changes of a long-term fertilization ifeld (from 1989) were determined to validate the predicted values. The results showed that the acid and alkali buffer capacities varied signiifcantly in the soil proifle, averaged 692 and 39.8 mmolc kg–1 pH–1, respectively. A signiifcant (P<0.05) correlation was found between pHBC and the content of calcium carbonate. Based on the commonly used application rate of urea (500 kg N ha–1 yr–1), the induced proton input in this region was predicted to be 16.1 kmol ha–1 yr–1, and nitriifcation and plant uptake of nitrate were the most important mechanisms for proton producing and consuming, respectively. The acidiifcation rate of topsoil (0–20 cm) was estimated to be 0.01 unit pH yr–1 at the assumed N fertilization level. From 1989 to 2009, topsoil pH (0–20 cm) of the long-term fertilization ifeld decreased from 8.65 to 8.50 for the PK (phosphorus, 150 kg P2O5 ha–1 yr–1;potassium, 300 kg K2O ha–1 yr–1; without N fertilization), and 8.30 for NPK (nitrogen, 300 kg N ha–1 yr–1; phosphorus, 150 kg P2O5 ha–1 yr–1; potassium, 300 kg K2O ha–1 yr–1), respectively. Therefore, the apparent soil acidiifcation rate induced by N fertilization equaled to 0.01 unit pH yr–1, which can be a reference to the estimated result, considering the effect of atmospheric N deposition, crop biomass, ifeld management and plant uptake of other

  1. Potential for Local Fertilization: A Benthocosm Test of Long-Term and Short-Term Effects of Mussel Excretion on the Plankton.

    Science.gov (United States)

    Cherif, Mehdi; Granados, Monica; Duffy, Sean; Robert, Pauline; Péquin, Bérangère; Mohit, Vani; McKindsey, Christopher W; Archambault, Philippe; Myrand, Bruno; Lovejoy, Connie; Tremblay, Réjean; Plourde, Stéphane; Fussmann, Gregor F

    2016-01-01

    Mussel aquaculture has expanded worldwide and it is important to assess its impact on the water column and the planktonic food web to determine the sustainability of farming practices. Mussel farming may affect the planktonic food web indirectly by excreting bioavailable nutrients in the water column (a short-term effect) or by increasing nutrient effluxes from biodeposit-enriched sediments (a long-term effect). We tested both of these indirect effects in a lagoon by using plankton-enclosing benthocosms that were placed on the bottom of a shallow lagoon either inside of a mussel farm or at reference sites with no history of aquaculture. At each site, half of the benthocosms were enriched with seawater that had held mussels (excretion treatment), the other half received non-enriched seawater as a control treatment. We monitored nutrients ([PO43-] and [NH4+]), dissolved oxygen and plankton components (bacteria, the phytoplankton and the zooplankton) over 5 days. We found a significant relationship between long-term accumulation of mussel biodeposits in sediments, water-column nutrient concentrations and plankton growth. Effects of mussel excretion were not detected, too weak to be significant given the spatial and temporal variability observed in the lagoon. Effects of mussels on the water column are thus likely to be coupled to benthic processes in such semi-enclosed water bodies.

  2. Potential for Local Fertilization: A Benthocosm Test of Long-Term and Short-Term Effects of Mussel Excretion on the Plankton.

    Directory of Open Access Journals (Sweden)

    Mehdi Cherif

    Full Text Available Mussel aquaculture has expanded worldwide and it is important to assess its impact on the water column and the planktonic food web to determine the sustainability of farming practices. Mussel farming may affect the planktonic food web indirectly by excreting bioavailable nutrients in the water column (a short-term effect or by increasing nutrient effluxes from biodeposit-enriched sediments (a long-term effect. We tested both of these indirect effects in a lagoon by using plankton-enclosing benthocosms that were placed on the bottom of a shallow lagoon either inside of a mussel farm or at reference sites with no history of aquaculture. At each site, half of the benthocosms were enriched with seawater that had held mussels (excretion treatment, the other half received non-enriched seawater as a control treatment. We monitored nutrients ([PO43-] and [NH4+], dissolved oxygen and plankton components (bacteria, the phytoplankton and the zooplankton over 5 days. We found a significant relationship between long-term accumulation of mussel biodeposits in sediments, water-column nutrient concentrations and plankton growth. Effects of mussel excretion were not detected, too weak to be significant given the spatial and temporal variability observed in the lagoon. Effects of mussels on the water column are thus likely to be coupled to benthic processes in such semi-enclosed water bodies.

  3. Effects of Long Term Application of Inorganic and Organic Fertilizers on Soil Organic Carbon and Physical Properties in Maize–Wheat Rotation

    Directory of Open Access Journals (Sweden)

    Babbu Singh Brar

    2015-06-01

    Full Text Available Balanced and integrated use of organic and inorganic fertilizers may enhance the accumulation of soil organic matter and improves soil physical properties. A field experiment having randomized complete block design with four replications was conducted for 36 years at Punjab Agricultural University (PAU, Ludhiana, India to assess the effects of inorganic fertilizers and farmyard manure (FYM on soil organic carbon (SOC, soil physical properties and crop yields in a maize (Zea mays–wheat (Triticum aestivum rotation. Soil fertility management treatments included were non-treated control, 100% N, 50% NPK, 100% NP, 100% NPK, 150% NPK, 100% NPK + Zn, 100% NPK + W, 100% NPK (-S and 100% NPK + FYM. Soil pH, bulk density (BD, electrical conductivity (EC, cation exchange capacity, aggregate mean weight diameter (MWD and infiltration were measured 36 years after the initiation of experiment. Cumulative infiltration, infiltration rate and aggregate MWD were greater with integrated use of FYM along with 100% NPK compared to non-treated control. No significant differences were obtained among fertilizer treatments for BD and EC. The SOC pool was the lowest in control at 7.3 Mg ha−1 and increased to 11.6 Mg ha−1 with 100%NPK+FYM. Improved soil physical conditions and increase in SOC resulted in higher maize and wheat yields. Infiltration rate, aggregate MWD and crop yields were positively correlated with SOC. Continuous cropping and integrated use of organic and inorganic fertilizers increased soil C sequestration and crop yields. Balanced application of NPK fertilizers with FYM was best option for higher crop yields in maize–wheat rotation.

  4. 长期施用不同肥料的土壤有机氮组分变化特征%Characteristics of Organic Nitrogen Fractions in Soils Under Long-term Different Fertilization

    Institute of Scientific and Technical Information of China (English)

    张玉树; 丁洪; 王飞; 郑祥洲; 翁伯琦; 林诚; 张晶

    2014-01-01

    A better understanding of organic nitrogen(N)fractions in soils under long-term fertilization is critical to the regulation of N fer-tilizers and eco-environmental quality. In this study, a organic N fractionation method by Bremner was used to examine the characteristics of soil organic N fractions under long-term applications of different fertilizers. Compared to no fertilizer(CK)treatment, total N and organic-N in soils increased under long-term fertilization. About half of the increased organic-N was acid-hydrolysable N and the rest was non-acid hydrolysable N. Of the increased acid hydrolysable N, hydrolysable unidentified N, amino acid N, amino sugar N and ammonia N accounted for about 69.0%, 21.0%, 6.6%, and 3.4%, respectively. Total N and organic-N in the soils applied with organic fertilizers plus chemical fertilizers were higher than those with chemical fertilizer alone. However, organic-N fractions changed differently under different organic fer-tilizers. In the soils applied with cattle manure combined with chemical fertilizers(NPKM), about 60.0% of the increased organic-N was acid-hydrolysable N, while 71.7% was non-acid hydrolysable N in the soils with straw plus chemical fertilizers(NPKS). These results indi-cate that the composition of organic materials would have great impact on the fractions and availability of organic N in soils.%采用 Bremner 有机氮分级方法研究了30年施用不同肥料的长期定位试验耕层土壤有机氮组分变化特征。结果表明,与不施肥(CK)处理相比,长期施用不同肥料均提高了耕层土壤全氮和有机氮含量,所增加的有机氮中酸解性氮和非酸解性氮各占一半左右,其中增加的酸解性氮有69.0豫为未知态氮,21.0豫为氨基酸氮,6.6豫为氨基糖氮,3.4豫为氨态氮。与单施化肥(NPK)相比,牛粪/稻草与化肥配施能进一步提高土壤全氮和有机氮含量,但是不同种类的有机肥与化肥配施所增加有机

  5. Short-term effects of fertilization on photosynthesis and leaf morphology of field-grown loblolly pine following long-term exposure to elevated CO2 concentration

    Science.gov (United States)

    Chris A. Maier; Sari Palmroth; Eric Ward

    2008-01-01

    We examined effects of a first nitrogen (N) fertilizer application on upper-canopy needle morphology and gas exchange in ~20-m-tall loblolly pine (Pinus taeda L.) exposed to elevated carbon dioxide concentration ([CO2]) for 9 years. Duke Forest free-air CO2 enrichment (FACE) plots were split and half of...

  6. Nitrogen turnover, crop use efficiency and soil fertility in a long-term field experiment amended with different qualities of urban and agricultural waste

    DEFF Research Database (Denmark)

    Gomez Muñoz, Beatriz; Magid, Jakob; Jensen, Lars Stoumann

    2017-01-01

    in a long-term field experiment with repeated application of different urban and agricultural organic waste amendments. Soils from the CRUCIAL field experiment in Denmark, in which diverse types of urban (human urine, sewage sludge, composted household waste) and agricultural wastes (cattle slurry, farmyard...... carbon, improved with the application of organic wastes. Cattle manure, sewage sludge and composted household waste in single or accelerated rates of application increased soil total N by 13–131% compared to the mineral fertiliser NPK treatment. The highest net N mineralisation capacity was observed...... for the accelerated rate of composted household waste, followed by all the other organic waste amendments and with the lowest net N mineralisation in the NPK-only and the unfertilised treatments. In soils amended for 11 years with NPK, human urine, cattle slurry, sewage sludge, cattle farmyard manure, cattle deep...

  7. 长期施肥对不同热量带土壤供氮能力的影响%Influence of Long-term Fertilization on Nitrogen Supply Capacity in Different Thermal Zones Soil

    Institute of Scientific and Technical Information of China (English)

    朱霞; 韩晓增; 乔云发; 李晓慧; 王守宇

    2009-01-01

    研究利用中国科学院海伦、栾城、鹰潭农业生态试验站长期定位试验,结合温室盆栽,研究了长期施肥对不同热量带土壤供氮能力的影响.为我国不同热量带下农田土壤的生产潜力,平衡施肥等提供理论依据.结果表明:长期不同施肥土壤全氮、碱解氮和矿质态氮含量的高低顺序均表现为:化肥+有机肥 > 化肥 > 无肥.长期施肥对红壤供氮能力的增加幅度最高,其次为潮褐土,最低为黑土,且长期施肥对土壤供氮能力的增加幅度与土壤所处热量带的有效积温呈显著正相关(P NPK > CK. Long-term fertilization en-hanced the capacity of soil nitrogen supply in different soils with an order of red soil > cinnamon soil > black soil. There was significant positive correlated relationship between the degree of long-term fertilization increased nitrogen supply ca-pacity and the effectively accumulated temperature ( P < 0.05) .In addition,crop biomass of fertilization soil was signifi-cantly higher than no fertilization soil, and the tendency of crop biomass was the same with the tendency of soil nitrogen content. It showed that crop biomass could be chosen as index for evaluating soil nitrogen supplying capacity

  8. 晋南长期免耕褐土肥力和酶活性的关系%Relationship between Soil Fertilities and Soil Enzyme Activities of Long-term No-tillage in Cinnamon Soil in South Shanxi

    Institute of Scientific and Technical Information of China (English)

    王恒飞; 张永清; 张水利; 景小元

    2012-01-01

    traditional Effects of long-term no-tillage on tillage and Long-term no-tillage District of Linfen total K, alkaline traditional tillage soil fertility, enzyme activities and their correlation were studied by using soil in ChengHuang experiment wheat field,which is located in Yaodu City in the loess plateau. The result indicated that N, available P, and available K soil were increased contents of soil organic matter, total N, total P, in the long-term no-l:illage soil, compared with soil. Activities of catalase, urease and invertase of the no-tillage soil were above the traditional tillage soil significantly. Soil enzyme activities correlates closely on fertility of long-term no-tillage soil,so the activities of catalase, urease and inverease of the no-tillage soil may be used for evaluating component analysis indicated that the years of no-tillage had significant impacted the soil fertility on the activities well. Principal and fertility of no-tillage soil. Long-term no-tillage is beneficial to soil fertility and sustainable development of agriculture. It is a feasible tillage pattern in arid and semiarid areas in the north of China%临汾市尧都区机械化保护性耕作试验示范区连续18年免耕覆盖(NTCS18)、连续12年免耕覆盖(NTCS12)、连续10年免耕覆盖(NTCS10)和传统耕作(CK)对土壤肥力和酶活性的影响研究结果表明,长期免耕提高了表层土壤有机质、碱解氮、速效磷、速效钾、全氮、全磷、全钾含量,并使表层土壤脲酶、蔗糖酶、过氧化氢酶活性显著增加;相关分析研究表明,长期免耕条件下土壤肥力与土壤酶活性间关系密切,蔗糖酶、过氧化氢酶、脲酶可以用来评价长期免耕土壤肥力状况;主成分分析法研究表明,长期免耕土壤肥力和酶活性信息系统主成分得分由高到低顺序为:NTCS18〉NTCS12〉NTCS10〉CK,说明长期免耕利于土壤肥力水平和酶活性提高,而且肥力水平和酶活

  9. [Effects of long-term mixed application of organic and inorganic fertilizers on canopy apparent photosynthesis and yield of winter wheat].

    Science.gov (United States)

    Zhao, Jun; Dong, Shu-ting; Liu, Peng; Zhang, Ji-wang; Zhao, Bin

    2015-08-01

    A field experiment was conducted using the winter wheat (Triticum aestivum) variety Shimai 15. The source of organic nitrogen was cow manure, and four fertilization treatments were included, i.e., no N fertilizer application, single application of urea, single application of cow manure, and mixed application of urea and cow manure. The effects of different applications of inorganic and organic nitrogen on canopy apparent photosynthesis (CAP), photosynthetic rate of flag leaves (Pn), leaf area index (LAI), florescence parameters and grain yield of winter wheat were determined. The results showed that urea had the largest effect on the early growth period, as at this stage the CAP, Pn and LAI of the single application of urea were the highest, which was followed by the mixed application and the single application of cow manure. However, 10 days after anthesis, the single application of cow manure and the mixed application delayed the leaf senescence process when compared with the single application of urea. This could be due to the two treatments having higher anti-oxidant enzyme activity and promoting a longer green leaf duration, which could maintain a higher photosynthetic capability. What' s more, the mixed application had a better performance and got the highest grain yield. Consequently, the mixed application of organic and inorganic fertilizers could delay leaf senescence and maintain a better canopy structure and higher photosynthesis capability at the late grain filling stage, which resulted in a higher grain yield.

  10. Long-Term Collections

    CERN Multimedia

    Comité des collectes à long terme

    2011-01-01

    It is the time of the year when our fireman colleagues go around the laboratory for their traditional calendars sale. A part of the money of the sales will be donated in favour of the long-term collections. We hope that you will welcome them warmly.

  11. Exploring the immediate and long-term impact on bacterial communities in soil amended with animal and urban organic waste fertilizers using pyrosequencing and screening for horizontal transfer of antibiotic resistance.

    Science.gov (United States)

    Riber, Leise; Poulsen, Pernille H B; Al-Soud, Waleed A; Skov Hansen, Lea B; Bergmark, Lasse; Brejnrod, Asker; Norman, Anders; Hansen, Lars H; Magid, Jakob; Sørensen, Søren J

    2014-10-01

    We investigated immediate and long-term effects on bacterial populations of soil amended with cattle manure, sewage sludge or municipal solid waste compost in an ongoing agricultural field trial. Soils were sampled in weeks 0, 3, 9 and 29 after fertilizer application. Pseudomonas isolates were enumerated, and the impact on soil bacterial community structure was investigated using 16S rRNA amplicon pyrosequencing. Bacterial community structure at phylum level remained mostly unaffected. Actinobacteria, Proteobacteria and Chloroflexi were the most prevalent phyla significantly responding to sampling time. Seasonal changes seemed to prevail with decreasing bacterial richness in week 9 followed by a significant increase in week 29 (springtime). The Pseudomonas population richness seemed temporarily affected by fertilizer treatments, especially in sludge- and compost-amended soils. To explain these changes, prevalence of antibiotic- and mercury-resistant pseudomonads was investigated. Fertilizer amendment had a transient impact on the resistance profile of the soil community; abundance of resistant isolates decreased with time after fertilizer application, but persistent strains appeared multiresistant, also in unfertilized soil. Finally, the ability of a P. putida strain to take up resistance genes from indigenous soil bacteria by horizontal gene transfer was present only in week 0, indicating a temporary increase in prevalence of transferable antibiotic resistance genes.

  12. Quantitative analyses of the abundance and composition of ammonia-oxidizing bacteria and ammonia-oxidizing archaea of a Chinese upland red soil under long-term fertilization practices.

    Science.gov (United States)

    He, Ji-Zheng; Shen, Ju-Pei; Zhang, Li-Mei; Zhu, Yong-Guan; Zheng, Yuan-Ming; Xu, Ming-Gang; Di, Hongjie

    2007-09-01

    The abundance and composition of soil ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) were investigated by using quantitative real-time polymerase chain reaction, cloning and sequencing approaches based on amoA genes. The soil, classified as agri-udic ferrosols with pH (H(2)O) ranging from 3.7 to 6.0, was sampled in summer and winter from long-term field experimental plots which had received 16 years continuous fertilization treatments, including fallow (CK0), control without fertilizers (CK) and those with combinations of fertilizer nitrogen (N), phosphorus (P) and potassium (K): N, NP, NK, PK, NPK and NPK plus organic manure (OM). Population sizes of AOB and AOA changed greatly in response to the different fertilization treatments. The NPK + OM treatment had the highest copy numbers of AOB and AOA amoA genes among the treatments that received mineral fertilizers, whereas the lowest copy numbers were recorded in the N treatment. Ammonia-oxidizing archaea were more abundant than AOB in all the corresponding treatments, with AOA to AOB ratios ranging from 1.02 to 12.36. Significant positive correlations were observed among the population sizes of AOB and AOA, soil pH and potential nitrification rates, indicating that both AOB and AOA played an important role in ammonia oxidation in the soil. Phylogenetic analyses of the amoA gene fragments showed that all AOB sequences from different treatments were affiliated with Nitrosospira or Nitrosospira-like species and grouped into cluster 3, and little difference in AOB community composition was recorded among different treatments. All AOA sequences fell within cluster S (soil origin) and cluster M (marine and sediment origin). Cluster M dominated exclusively in the N, NP, NK and PK treatments, indicating a pronounced difference in the community composition of AOA in response to the long-term fertilization treatments. These findings could be fundamental to improve our understanding of the importance of

  13. Profiling of soil volatile organic compounds after long-term application of inorganic, organic and organic-inorganic mixed fertilizers and their effect on plant growth.

    Science.gov (United States)

    Raza, Waseem; Mei, Xinlan; Wei, Zhong; Ling, Ning; Yuan, Jun; Wang, Jichen; Huang, Qiwei; Shen, Qirong

    2017-12-31

    The complexity of soil processes involved in the production, consumption and accumulation of volatile organic compounds (VOCs) makes hard to access the overall dynamics of VOCs in the soil. In this study, the field soil, applied with inorganic (CF), organic (OF) and inorganic-organic mixed (CFOF) fertilizers for ten years was evaluated for the emission of VOCs at different temperature and moisture levels. We identified 30-50 soil emitted VOCs representing the most common soil VOCs groups by using the solid-phase microextraction (SPME) fiber and gas chromatography-mass spectroscopy. The highest total emission of VOCs was found in OF treatment, but it was non-significantly different with CF treatment. The emission of VOCs was significantly increased with the decrease in moisture contents and increase in the temperature of the soil. Among different fertilizer treatments, the emission of VOCs was significantly higher in OF treatment at 5% moisture, and in CF and OF treatments at 35°C. Further, the VOCs emitted from soil treated with CFOF showed the highest increase in plant growth while CF and OF treatments showed similar results. The VOCs were also extracted from the soil using methanol to better understand the dynamics of VOCs. The abundance of VOCs extracted from the soil was 44-61%, while the richness was 65-70% higher than the VOCs emitted from the soil in different treatments. Taken together the results of emitted and extracted VOCs from the soil, we conclude that the fertilizers are able to discriminate among the VOC patterns of soil. In addition, most of the VOCs are retained in the soil and the emission of VOCs from soil depends on the type of VOCs, soil properties and environmental conditions; however, more research is required to find out better soil VOCs analysis methods. Copyright © 2017. Published by Elsevier B.V.

  14. Effects of Long-term Fertilization on Phosphorus Supply Capacity and Availability in Black Soil%长期施肥对黑土供磷能力及磷素有效性的影响

    Institute of Scientific and Technical Information of China (English)

    陈欣; 韩晓增; 宋春; 梁尧; 丁雪丽

    2012-01-01

    [Objective] The research aimed to study the effects of long-term fertilization on phosphorus supply capacity, phosphorus fractions transformation in black soil. [Method] The soil samples of pot experiment were collected from a long-term field experiment which carried on Hailun Agricultural Ecology Station of Chinese Academy of Sciences. Experimental treatments included without fertilizer application ( CK), applying chemical nitrogen and phosphorus fertilizer (NP), and applying N and P fertilizer and organic manure ( NPM). Phosphorus fractions transformation during biological depletion was studied by Hedley' s P fractionation method. [ Result] Compared with no fertilizer application, applying chemical fertilizer and chemical fertilizer with organic manure could increase contents of different forms of phosphorus. The biological depletion pot experiment showed that plant biomass in NPM was 31.72% higher than NP and 54.65% higher than CK. The amounts of plant P uptake in NPM were 1.7 and 2. 1 times higher than those of NP and CK soils, respectively. The concentrations of resin-P in NPM only decreased 0. 85% , which was much lower than that of CK and NP after two successive growing seasons. [Conclusion] Long-term application of chemical fertilizer with organic manure can maintain a high level of reactive P content, improve soil Phosphorus supply capacity and productivity in the agroecosystem.%[目的]研究长期施肥后黑土供磷能力、磷素形态的变化.[方法]利用采自海伦农田生态系统国家野外科学观测研究站长期定位试验地的无肥(CK)、化肥(NP)、化肥配施有机肥( NPM)3个施肥处理黑土进行生物耗竭盆栽试验,并用Hedley方法对土壤磷素形态进行研究.[结果]与长期不施肥处理相比,施化肥与化肥配施有机肥均能明显增加土壤各形态磷素;与无肥处理土壤相比,化肥有机肥配施处理土壤与化肥处理土壤植株的生物量增幅分别为31.72%和54.65%;植

  15. Temporal and spatial dynamics of enzyme activities under long-term fertilization in a maize growing brown soil%长期不同施肥棕壤玉米地酶活性的时空变化

    Institute of Scientific and Technical Information of China (English)

    兰宇; 韩晓日; 杨劲峰; 王月; 房大伟; 李娜

    2011-01-01

    为揭示长期不同施肥对棕壤玉米地酶活性时空变化的影响,利用31年长期肥料定位试验研究了玉米生育期内3种主要土壤酶活性的时空变化及其与土壤理化性质的关系。结果表明,棕壤上各种酶活性随玉米生育期推进而有规律地变化。土壤脲酶、转化酶活性高峰出现在玉米拔节期,酸性磷酸酶活性高峰出现在玉米大喇叭口期;玉米收获后,土壤转化酶、脲酶均高于播前或与播前相当,而酸性磷酸酶活性则低于播前。在同样化肥水平卜增施有机肥能增加脲酶、转化酶活性,而降低酸性磷酸酶活性;3种酶活性的空间分布均遵循随土层深度加深而不断减小的规律,长期培肥对深层土壤酶活性亦有影响。相关分析结果显示,土壤脲酶与转化酶呈极显著正相关(r=0.636^**);脲酶、转化酶与土壤有机碳、pH、含水量、碱解氮、速效磷基本呈极显著正相关;酸性磷酸酶与各因子无显著相关关系。土壤酶与土壤肥力因素关系密切,可作为衡量土壤肥力的敏感指标。%A long-term fertilizer location experiment (31 years) was carried out to study the temporal and spatial dynamics of enzyme activities under long-term fertilization in a maize growing brown soil. Results showed that enzyme activities changed regularly with the growing of maize. The highest urease and invertase activities were observed at jointing stage, while the highest acid phosphatase activity at the huge bellbottom period. Urease and invertase activities were higher after harvest than before sowing, however acid phosphatase activity was lower after harvest. With same application rate of chemical fertilizer, application of organic fertilizer could increase urease and invertase activities, but decrease acid phosphatase activity. All of the three enzyme activities decreased with the depth soil profile. Long-term fertilization could also affect

  16. Carbon Storage and Carbon Dioxide Emission as Influenced by Long-term Conservation Tillage and Nitrogen Fertilization in Corn-Soybean Rotation

    Directory of Open Access Journals (Sweden)

    Rahmat Saleh

    2012-01-01

    Full Text Available Although agriculture is a victim of environmental risk due to global warming, but ironically it also contributes toglobal greenhouse gas (GHG emission. The objective of this experiment was to determine the influence of long-termconservation tillage and N fertilization on soil carbon storage and CO2 emission in corn-soybean rotation system. Afactorial experiment was arranged in a randomized completely block design with four replications. The first factorwas tillage systems namely intensive tillage (IT, minimum tillage (MT and no-tillage (NT. While the second factorwas N fertilization with rate of 0, 100 and 200 kg N ha-1 applied for corn, and 0, 25, and 50 kg N ha-1 for soybeanproduction. Samples of soil organic carbon (SOC after 23 year of cropping were taken at depths of 0-5 cm, 5-10cm and 10-20 cm, while CO2 emission measurements were taken in corn season (2009 and soybean season (2010.Analysis of variance and means test (HSD 0.05 were analyzed using the Statistical Analysis System package. At 0-5 cm depth, SOC under NT combined with 200 kg N ha-1 fertilization was 46.1% higher than that of NT with no Nfertilization, while at depth of 5-10 cm SOC under MT was 26.2% higher than NT and 13.9% higher than IT.Throughout the corn and soybean seasons, CO2-C emissions from IT were higher than those of MT and NT, whileCO2-C emissions from 200 kg N ha-1 rate were higher than those of 0 kg N ha-1 and 100 kg N ha-1 rates. With any Nrate treatments, MT and NT could reduce CO2-C emission to 65.2 %-67.6% and to 75.4%-87.6% as much of IT,respectively. While in soybean season, MT and NT could reduce CO2-C emission to 17.6%-46.7% and 42.0%-74.3% as much of IT, respectively. Prior to generative soybean growth, N fertilization with rate of 50 kg N ha-1could reduce CO2-C emission to 32.2%-37.2% as much of 0 and 25 kg N ha-1 rates.

  17. Studies on long-term impact of STCR based integrated fertilizer use on pearl millet (Pennisetum glaucum)-wheat (Triticum aestivum) cropping system in semi arid condition of India.

    Science.gov (United States)

    Sharma, V K; Pandey, R N; Sharma, B M

    2015-01-01

    A long-term field experiment on pearl millet - wheat cropping system with soil test crop response correlation (STCR) based fertilizer application was initiated during kharif- 2003 on a sandy loam soil (Typic Halustept) at a research farm of Indian Agricultural Research Institute, New Delhi. The aim of the experiment was to study the impact of STCR based integrated fertilizer application for targeted yield of pearl millet - wheat cropping sequence yield and changes in soil health. The result showed a significant and positive impact of integrated use of the fertilizerwith FYM on productivity of the cropping sequence and soil fertility. The STCR based integrated fertilizer recommendations with FYM produced significantly higher grain and straw yields of pearl millet and wheat crops as compared to other treatments. The highest average (2003 to 2010-11) grain and straw yield of pearl millet (2.85 and 6.59 t ha(-1)) and wheat (5.32 and 7.17 t ha(-1)) was recorded with the application of STCR based integrated fertilizer recommendations (T2) for targeted level of yield 2.5 and 5.0 ha(-1), respectively. Average increase in grain and straw yield of pearl millet was 203 and 197% and 196 and 193% of wheat under T2 treatment over control (T4). After harvest of wheat crops (2010-11), the physical, biological properties and fertility status i.e. available N, P and K of soil were improved in the treatments where STCR based integrated fertilizer dose with 10 t FYM (T2) and FYM @20 t ha(-1)(T1) were applied in both the crops and were significantly higher as compared to T3 treatment except available phosphorus. Economic analysis based on average yield of eight cropping sequence (2003 to 2010-11), pearl millet - wheat cropping sequence gave maximum net return of Rs. 100,907 ha(-1) yr(-1) and total return of Rs. 64,992/ ha(-1)yr(-1) over control with STCR based integrated fertilizer recommendations (T2). It is concluded that STCR based integrated fertilizer can be adopted by the farmers

  18. The impacts of different long-term fertilization regimes on the bioavailability of arsenic in soil: integrating chemical approach with Escherichia coli arsRp::luc-based biosensor.

    Science.gov (United States)

    Hou, Qi-Hui; Ma, An-Zhou; Lv, Di; Bai, Zhi-Hui; Zhuang, Xu-Liang; Zhuang, Guo-Qiang

    2014-07-01

    An Escherichia coli arsRp::luc-based biosensor was constructed to measure the bioavailability of arsenic (As) in soil. In previous induction experiments, it produced a linear response (R (2) = 0.96, P bioavailability of arsenic (As) in soil. Per the BCR-SEPs analysis, the application of M and M + NPK led to a significant (P bioavailable As in manure-fertilized (M and M + NPK) soil was significantly higher (P bioavailable As. More significantly, E. coli biosensor-determined As was only 18.46-85.17 % of exchangeable As and 20.68-90.1 % of reducible As based on BCR-SEPs. In conclusion, NKP fertilization was recommended as a more suitable regime in As-polluted soil especially with high As concentration, and this E. coli arsRp::luc-based biosensor was a more realistic approach in assessing the bioavailability of As in soil since it would not overrate the risk of As to the environment.

  19. Long-term Fertilization Impacts on Hg in A Typical Fluvo-aquil Soil%长期施肥对典型壤质潮土中汞的影响

    Institute of Scientific and Technical Information of China (English)

    王擎运; 张佳宝; 赵炳梓; 邓西海; 信秀丽; 陈吉; 钦绳武

    2013-01-01

    利用典型壤质潮土上的田间试验,分析长期不同施肥处理条件下土壤中汞(Hg)含量的变化,探讨了Hg在该类型农田生态系统中的来源、去向及累积趋势.结果表明,经过长期不同施肥处理,Hg在表层土壤(0~20 cm)中的含量呈现先增加后减少的趋势,不同处理间则表现为NPK≈NP≈PK≈OM+NPK(有机肥及无机肥各占一半)>OM(有机肥)>NK≈CK(对照,不施肥).Hg在土层中以向下迁移为主,0~ 40 cm土层中Hg的含量变化明显,但底层土壤(40~60 cm)中的含量变化较小.Hg在次表层土壤(20~40 cm)中的持续累积是表层土壤中Hg的重要去向,也致使Hg的生态风险更为隐蔽.Hg在壤质潮土中的含量,主要受到磷肥、有机肥、及灌溉水的影响,受到氮肥和钾肥的影响相对较小.其中,磷肥的施用是目前造成Hg在壤质潮土中累积的主要原因.%This experiment was conducted since 1989 to study soil Hg balance and transfer with soil depth under the influence of long-term fertilization.Hg contents of surface soils in different treatments increased first and then decreased,in an order of NPK≈ NP ≈ PK≈ OM+NPK (Half organic fertilizer + Half chemical fertilizer) > OM (Organic fertilizer) >NK≈ CK (Control,no fertilization).Hg contents in some treatments were higher than the background value due to the use of phosphate fertilizer.Hg content in soil depth (0-40 cm) was affected more by long-term different fertilization than the underlying soil (40-60 cm).Hg transferred downwards mainly in soil and accumulated in subsurface soils (20-40 cm) continually,which may hide the ecological risk of Hg.Hg content in soil was mainly affected by phosphate and organic matter fertilizers as well as irrigation water,but less affected by nitrogenous or potassium fertilizers,and the use of phosphorus fertilizer was the major reason which caused the accumulation of Hg in soil.

  20. Associations between soil bacterial community structure and nutrient cycling functions in long-term organic farm soils following cover crop and organic fertilizer amendment.

    Science.gov (United States)

    Fernandez, Adria L; Sheaffer, Craig C; Wyse, Donald L; Staley, Christopher; Gould, Trevor J; Sadowsky, Michael J

    2016-10-01

    Agricultural management practices can produce changes in soil microbial populations whose functions are crucial to crop production and may be detectable using high-throughput sequencing of bacterial 16S rRNA. To apply sequencing-derived bacterial community structure data to on-farm decision-making will require a better understanding of the complex associations between soil microbial community structure and soil function. Here 16S rRNA sequencing was used to profile soil bacterial communities following application of cover crops and organic fertilizer treatments in certified organic field cropping systems. Amendment treatments were hairy vetch (Vicia villosa), winter rye (Secale cereale), oilseed radish (Raphanus sativus), buckwheat (Fagopyrum esculentum), beef manure, pelleted poultry manure, Sustane(®) 8-2-4, and a no-amendment control. Enzyme activities, net N mineralization, soil respiration, and soil physicochemical properties including nutrient levels, organic matter (OM) and pH were measured. Relationships between these functional and physicochemical parameters and soil bacterial community structure were assessed using multivariate methods including redundancy analysis, discriminant analysis, and Bayesian inference. Several cover crops and fertilizers affected soil functions including N-acetyl-β-d-glucosaminidase and β-glucosidase activity. Effects, however, were not consistent across locations and sampling timepoints. Correlations were observed among functional parameters and relative abundances of individual bacterial families and phyla. Bayesian analysis inferred no directional relationships between functional activities, bacterial families, and physicochemical parameters. Soil functional profiles were more strongly predicted by location than by treatment, and differences were largely explained by soil physicochemical parameters. Composition of soil bacterial communities was predictive of soil functional profiles. Differences in soil function were

  1. Effect of Long-Term Different Fertilization on Maize Yield Stability in the Northeast Black Soil Region%长期不同施肥对东北黑土区玉米产量稳定性的影响

    Institute of Scientific and Technical Information of China (English)

    高洪军; 彭畅; 张秀芝; 李强; 朱平

    2015-01-01

    [Objective]This research was conducted to reveal the stability difference and dynamic of maize yield in the Northeast Black Soil region of China, and to provide scientific references for establishing the optimal fertilization pattern and promoting the sustainable production of maize.[Method]Based on the long-term experiment on Black Soil fertility and fertilizer efficiency in Gongzhuling city of Jilin province, the respond of maize yield and soil nutrient to eight fertilization patterns were analyzed: non-fertilization (CK), application of single chemical NP (NP), application of single chemical NK (NK), application of single chemical PK (PK), application of single chemical NPK (NPK), mixed application of low amounts of chemical fertilizer and manure (M1NPK), chemical fertilizer plus maize straw (SNPK), and mixed application of high amount chemical fertilizer and manure M2NPK).[Result]It was discovered that maize yield in chemical fertilizer plus organic manure treatments showed a significant increasing trend. There were no significant differences in average yields among the M1NPK, SNPK, and NPK treatments, in which the same N amounts were applied. The NPK treatment had a higher maize yield than the M1NPKand SNPK treatments in the first eleven years, but the result was the opposite in the recent fourteen years. Maize average yields of chemical fertilizer treatments showed an order of NPK>NP>NK>PK and CK during a 25 year period. The yield effects of chemical fertilizers N, P, and K were 33.0, 16.2, and 5.3 kg·kg-1 respectively. The application of organic fertilizer and chemical fertilizer had a higher sustainable yield index (SYI) from 0.712 to 0.798, but theSYI was very low in imbalance fertilization and no fertilizer treatments. The coefficient variation (CV) of maize yield was greater in the CK, PK, or NK treatments, which ranged from 18.5% to 34.7%, while the organic and inorganic fertilizer treatments had a lower CV of between 10.8%-13.0%. The average

  2. Relation between soil P test values and mobilization of dissolved and particulate P from the plough layer of typical Danish soils from a long-term field experiment with applied P fertilizers

    DEFF Research Database (Denmark)

    Glæsner, Nadia Andersen; Kjærgaard, Charlotte; Rubæk, Gitte Holton

    2013-01-01

    Accumulation of phosphorus (P) in agricultural topsoils can contribute to leaching of P which may cause eutrophication of surface waters. An understanding of P mobilization processes in the plough layer is needed to improve agricultural management strategies. We compare leaching of total dissolved...... and particulate P through the plough layer of a typical Danish sandy loam soil subjected to three different P fertilizer regimes in a long-term field experiment established in 1975. The leaching experiment used intact soil columns (20 cm diameter, 20 cm high) during unsaturated conditions. The three soils had...... in particulate P (PP) with increasing labile P content was modest and statistically insignificant. We found concentrations up to 1.5 mg TP/L for the plough layer of this typical Danish sandy loam soil. This highlights that even a moderate labile P content can be a potential source of TDP from the plough layer...

  3. 长期施肥砂姜黑土微生物学特征差异及评价%Difference and assessment in microbial characteristics of lime concretion black soil affected by long-term fertilization

    Institute of Scientific and Technical Information of China (English)

    陈欢; 曹承富; 张存岭; 李玮; 乔玉强; 赵竹; 杜世州; 张向前

    2015-01-01

    [Objectives] Being a major part of low-yielding soil types in Anhui province , lime concretion black soil restrains crop yields from increasing and stabilizing owing to its intrinsic properties . Based on a long-term fertilization experiment , responses of soil microbial properties to different fertilizer application were explored , which can provide a theoretical mechanism and support for improving lime concretion black soil ecological function a nhancing soil productive sustainability .[Methods] The long-term fertilization experiment , located in Yangliu Village of Anhui Province , was started since 1981 , wheat and corn have been rotationally planted , all the straws are removed out of the plots after harvest .Five treatments were designed: non-fertilized ( CK ) , mineral fertilizer ( NPK) , organic fertilizer ( M ) , mineral plus organic fertilizer ( mineral N:organic N =1:1 , MNPK ) , and mineral plus organic fertilizer with higher amount of nitrogen ( HMNPK ) .We investigated number of bacteria , fungi and actinomycete , microbial biomass-carbon ( SMBC ) and microbial biomass-nitrogen ( SMBN ) , and activities of urease , invertase , acid and neutral phosphatase .Principal components analysis was used to evaluate soil micro-ecosystem quality in different fertilization .[Results] 1 ) Compared with CK , the organic fertilizer treatments ( M、 MNPK and HMNPK ) significantly increased soil culturable microbes by 15.68-22.80 times, especially bacteria and actinomycete , the maxima were in treatment of M and MNPK with value of 30.50 ×10 5 and 15.50 ×104 cfu/g, respectively.The fungi was inhibited by M, but increased obviously by NPK.2) The SMBC and SMBN were reinforced by the organic fertilizers (M, MNPK and HMNPK), in which the maximal increments in SMBC and SMBN appeared in treatment of MNPK ( 119.74% and 88.46%); NPK treatment enhanced the SMBC significantly (38.87%) , but affected SMBN slightly .3 ) The activities of soil urease and invertase were increased

  4. 长期施肥对水稻光合特性及水分利用效率的影响%Effects of long-term fertilization on rice photosynthetic traits and water use efficiency

    Institute of Scientific and Technical Information of China (English)

    袁颖红; 樊后保; 黄欠如; 廖迎春; 黄荣珍

    2009-01-01

    A field experiment has being conducted for 27 years in Jinxian County, Institute of Red Soil in Jiangxi Province (116°20'24" E, 28°15'30" N) to study the effects of fertilization on the rice photosynthetic traits and water use efficiency. Four treatments were installed,i. e., no fertilization (CK), chemical fertilization (N, NP, NPK), organic fertilization (M), and chemi-cal and organic fertilization (NPKM). Long-term fertilization, especially treatment NPKM, in- creased the flag leaf chlorophyll content, net photosynthetic rate, stomatal conductance, transpi-ration rate, and water use efficiency of rice at its all growth stages and the rice yield, and de-creased the flag leaf intercellular CO_2 concentration. With the growth of rice, the chlorophyll content, net photosynthetic rate, stomatal conductance, and transpiration rate decreased, but the intercellular CO_2 concentration increased. The water use efficiency was the greatest at full-head-ing stage. There were significant positive correlations between the chlorophyll content and net photosynthetic rate at various growth stages and the rice yield, Long-term fertilization, especially the combined chemical and organic fertilization, was favorable to the rice growth and develop-ment, water use efficiency, and yield production in red soil region.%在实施了27年的长期田间定位试验区,研究了长期不同施肥对红壤区水稻光合特性及水分利用效率的影响.结果表明:在不施肥(CK)、无机肥(N、NP、NPK)、有机肥(猪粪+紫云英绿肥,M)和无机肥与有机肥配施(NPKM)处理中,长期施用肥料,特别是有机肥与无机肥配施提高水稻各生育期剑叶叶绿素含量、净光合作用速率、气孔导度、蒸腾速率、水分利用效率和水稻产量,降低水稻剑叶胞间CO_2浓度;水稻剑叶叶绿素含量、净光合作用速率、气孔导度、蒸腾速率随发育阶段演进而减小,孕穗期>齐穗期>乳熟期,而胞间CO_2浓度相反;水分利

  5. 长期不同施肥处理对华北潮土酶活性的影响%Soil Enzyme Levels in Fluvo-auic Soil with Different Long-term Fertilization in North China Plain

    Institute of Scientific and Technical Information of China (English)

    李芳; 张佳宝; 信秀丽; 张丛志; 宁琪; 赵金花; 吴其聪; 赵占辉; 蔡太义; 聂广森

    2015-01-01

    酶产生显著影响。%Soil enzyme activities, as an important biological indicator of soil fertility, can quickly reflect the change of soil properties. In order to improve the fertility of fluvo-auic soil, we assessed the effects of long-term fertilization on Soil enzyme activities. Based on two long-term fertilization experiments located in Zhengzhou and Fengqiu, the activities of urease, alkaline phospahtase, catalase, protease and invertase under different fertilization treatments in plough layer soil (0~15 cm) were investigated, as well as the correlations between soil enzyme activities and soil chemical properties were analyzed. The results showed that: (1) Although both of topsoil types at two field experiments were fluvo-auic soil, the effects of different fertilization on soil enzyme activities were very different. Soil catalase activities was not significant influenced by long-term fertilization in Zhengzhou, whereas NK fertilization increased the soil catalase activities by 58.3% compared with control in Fengqiu. (2) Without the application of phosphate fertilizer, protease activity increased by 119% compared with the control when the ratio of nitrogen and potassium was 1∶1; however, protease activity descended by 20% when the ratio was 2∶1. (3) Different fertilization was helpful for the urease enzyme activity, and the highest urease enzyme activity was found in organic compost treated soil, which increased by 41.1% and 106.4% in Zhengzhou and Fengqiu, respectively. (4) Long-term fertilization did not significantly increase the soil alkaline phosphatase activity, nevertheless the straw incorporated treatment dominantly induce the activity of alkaline phosphatase by the percent of 133.5% in comparison with that in the CK plots; (5) Invertase activity of all fertilization treated soil was improved in Zhengzhou, and the increase ranged 95.5% in the NK plots to 439% in straw incorporated fertilizer plots. In Fengqiu, compared to the control, NK,OM fertilization improved the invertase

  6. Long-Term Collections

    CERN Multimedia

    Staff Association

    2016-01-01

    45 years helping in developing countries! CERN personnel have been helping the least fortunate people on the planet since 1971. How? With the Long-Term Collections! Dear Colleagues, The Staff Association’s Long-Term Collections (LTC) Committee is delighted to share this important milestone in the life of our Laboratory with you. Indeed, whilst the name of CERN is known worldwide for scientific discoveries, it also shines in the many humanitarian projects which have been supported by the LTC since 1971. Several schools and clinics, far and wide, carry its logo... Over the past 45 years, 74 projects have been supported (9 of which are still ongoing). This all came from a group of colleagues who wanted to share a little of what life offered them here at CERN, in this haven of mutual understanding, peace and security, with those who were less fortunate elsewhere. Thus, the LTC were born... Since then, we have worked as a team to maintain the dream of these visionaries, with the help of regular donat...

  7. Long-Term Collection

    CERN Document Server

    Staff Association

    2016-01-01

    Dear Colleagues, As previously announced in Echo (No. 254), your delegates took action to draw attention to the projects of the Long-Term Collections (LTC), the humanitarian body of the CERN Staff Association. On Tuesday, 11 October, at noon, small Z-Cards were widely distributed at the entrances of CERN restaurants and we thank you all for your interest. We hope to have achieved an important part of our goal, which was to inform you, convince you and find new supporters among you. We will find out in the next few days! An exhibition of the LTC was also set up in the Main Building for the entire week. The Staff Association wants to celebrate the occasion of the Long-Term Collection’s 45th anniversary at CERN because, ever since 1971, CERN personnel have showed great support in helping the least fortunate people on the planet in a variety of ways according to their needs. On a regular basis, joint fundraising appeals are made with the Directorate to help the victims of natural disasters around th...

  8. Collectes à long terme

    CERN Document Server

    Collectes à long terme

    2014-01-01

    En cette fin d’année 2014 qui approche à grands pas, le Comité des Collectes à Long Terme remercie chaleureusement ses fidèles donatrices et donateurs réguliers pour leurs contributions à nos actions en faveur des plus démunis de notre planète. C’est très important, pour notre Comité, de pouvoir compter sur l’appui assidu que vous nous apportez. Depuis plus de 40 ans maintenant, le modèle des CLT est basé principalement sur des actions à long terme (soit une aide pendant 4-5 ans par projet, mais plus parfois selon les circonstances), et sa planification demande une grande régularité de ses soutiens financiers. Grand MERCI à vous ! D’autres dons nous parviennent au cours de l’année, et ils sont aussi les bienvenus. En particulier, nous tenons à remercier...

  9. Long-term tumor control and fertility after limited paraaortic radiotherapy in stage I seminoma; Langzeittumorkontrolle und Fertilitaet nach paraaortal limitierter Radiotherapie des Seminoms im Stadium I

    Energy Technology Data Exchange (ETDEWEB)

    Sedlmayer, F.; Deutschmann, H.; Rahim, H.; Merz, F.; Kogelnik, H.D. [Landeskliniken Salzburg (Austria). Inst. fuer Radiotherapie und Radio-Onkologie; Joos, H. [Landeskliniken Salzburg (Austria). Urologische Abt.

    1999-07-01

    Purpose: To review patterns of relapse in a long-term analysis of patients with Stage I seminoma treated by orchidectomy and radiotherapy to the paraaortic lymph nodes only and to follow follicle stimulating hormone (FSH) levels dependent on testicular scatter dose. Patients and methods: From 1980 to 1995, 58 patients with Stage I seminoma received elective radiotherapy to the paraaortic lymph nodes only (Th12 to L4), with a mean total dose of 28.07 Gy ({+-}2.2 SD), using fractional doses between 1.5 and 2 Gy (mean 1.62 Gy{+-}0.083 SD). Since 1989, testicular scatter doses were measured routinely by in-vivo thermoluminescent dosimetry (TLD) in 45 patients. In 26 patients with normal pre-treatment values of FSH, FSH-levels were repeatedly controlled after radiotherapy in order to evaluate any radiation-induced sequelae. Results: During a mean observation period of 69.4 months (range 30 to 210), 2 out of 57 patients (3.5%) developed regional recurrences in the ipsilateral pelvic lymph nodes 14 months and 5 years after radiotherapy, respectively. One patient was lost to follow-up. The relapse-free survival rate at 5 years was 96.5% after radiotherapy alone. After salvage chemotherapy, both relapse-free survival and overall survival rates came to 100%. The mean testicular scatter dose in 45 patients was 0.22 Gy ({+-}0.087 SD). Seven out of 26 patients (26.9%) developed a transient increase of FSH-levels, reaching peak values at 4.2 months and returning to normal ranges within 18 months after radiotherapy. Below 0.2 Gy, no effect on FSH was observed. Testicular scatter doses showed no clear correlation to FSH risings. Conclusion: After exclusive paraaortic radiation of Stage I seminoma, even at follow-up periods in excess of 5 years the incidence of pelvic lymph node relapses remains below 4%. However, there seems to be a small potential for the development of late recurrences. With limited radiotherapy, permanent radiation-induced effects on the remaining testicle are

  10. Effects of Long-term Different Fertilization on Inorganic Phosphorus Forms in Cinnamon Soil%长期施用不同肥料对栗褐土无机磷组分的影响

    Institute of Scientific and Technical Information of China (English)

    杨艳菊; 王改兰; 王振宙; 聂冰; 熊静; 黄学芳

    2011-01-01

    The effects of long-term fertilization on inorganic phosphorus fractions in lime concretion cinnamon soil were studied using the fraction classification developed by Gu Yi-chu and Jiang Bo-fan. The results show that Long-term application of chemical phosphorus and manure fertilizer may increase the inorganic phosphorus. The main of inorganic phosphorus in cinnamon soil is Ca-P which takes up 80. 0% ,in the next place are O-P,Fe-P and Al-P. Under the Long-term application of chemical phosphorus and manure fertilizer, the components pool of inor ganic phosphorus have increased compared with non-fertilization, except of nitrogen fertilization. In inorganic phos phorus,the related coefficient between Ca2-P, Ca8-P, Calo-P, Al-P, Fe-P and Olsen-P are 0.976 7,0. 886 5, 0.915 5,0.860 2,0.848 4,which reach significant positive relationship,except O-P. Ca2-P,Al-P,Fe-P and Ca10-P are the main sources of Olsen-P can be found by path analysis.%采用顾益初、蒋柏藩的无机磷分级方法,研究了长期施肥条件下栗褐土无机磷组分含量变化及其与土壤有效磷的关系.结果表明:长期施用磷肥和有机肥均能促进栗褐土中无机磷的积累,有机肥与磷肥配施效果更加明显.Ca-P是栗褐土无机磷的主体,占无机磷总量的80.0%,其次是O-P、Fe-P和A1-P.长期施肥处理的无机磷各组分含量与不施肥处理相比均有所增加,而单施氮肥处理无机磷各组分略有下降.无机磷中Ca2-P、Ca8-P、Ca10-P、A1-P、Fe-P与Olsen-P相关系数分别为0.976 7,0.886 5,0.915 5,0.860 2,0.848 4,均达极显著水平,O-P与Olsen-P的相关性不显著.通径分析表明Ca2-P、Al-P、Fe-P、Ca10-P为Olsen-P的主要磷源.

  11. Estimating the long-term effects of in vitro fertilization in Greece: an analysis based on a lifetime-investment model

    Directory of Open Access Journals (Sweden)

    Fragoulakis V

    2013-06-01

    Full Text Available Vassilis Fragoulakis, Nikolaos ManiadakisNational School of Public Health, Department of Health Services Management, Athens, GreeceObjective: To quantify the economic effects of a child conceived by in vitro fertilization (IVF in terms of net tax revenue from the state's perspective in Greece.Methods: Based on previous international experience, a mathematical model was developed to assess the lifetime productivity of a single individual and his/her lifetime transactions with governmental agencies. The model distinguished among three periods in the economic life cycle of an individual: (1 early life, when the government primarily contributes resources through child tax credits, health care, and educational expenses; (2 employment, when individuals begin returning resources through taxes; and (3 retirement, when the government expends additional resources on pensions and health care. The cost of a live birth with IVF was based on the modification of a previously published model developed by the authors. All outcomes were discounted at a 3% discount rate. The data inputs – namely, the economic or demographic variables – were derived from the National Statistical Secretariat of Greece and other relevant sources. To deal with uncertainty, bias-corrected uncertainty intervals (UIs were calculated based on 5000 Monte Carlo simulations. In addition, to examine the robustness of our results, other one-way sensitivity analyses were also employed.Results: The cost of IVF per birth was estimated at €17,015 (95% UI: €13,932–€20,200. The average projected income generated by an individual throughout his/her productive life was €258,070 (95% UI: €185,376–€339,831. In addition, his/her life tax contribution was estimated at €133,947 (95% UI: €100,126–€177,375, while the discounted governmental expenses for elderly and underage individuals were €67,624 (95% UI: €55,211–€83,930. Hence, the net present value of IVF was €60

  12. Effect of Long-term Fertilization on Soil Organic Carbon and Soil Inorganic Carbon in Oasis Cropland%长期施肥对绿洲农田土壤有机碳和无机碳的影响

    Institute of Scientific and Technical Information of China (English)

    荣井荣; 李晨华; 王玉刚; 唐立松; 陈效民

    2012-01-01

    以中国科学院阜康荒漠生态站的绿洲农田养分循环长期定位试验(始于1990年)为研究平台,研究了无施肥处理(CK)、单施化肥处理(NPK)、有机/无机配施处理(NPKM)和秸秆还田处理(NPKS)下,土壤无机碳(SIC)和有机碳(SOC)在剖面和各施肥年限的含量变化特征及其影响。结果表明:施肥、剖面层次和施肥年限对SOC与SIC含量变化影响显著(P〈0.01)。在各施肥处理中,与CK相比,NPK、NPKM和NPKS的SOC与SIC含量明显增加(P〈0.05),并且有机/无机肥配施模式下的SIC含量显著高于单施化肥模式;在剖面层次间,SIC含量从0~20cm的9.12 g/kg增加到40~60 cm的9.94 g/kg,而SOC变化趋势与之相反。表明合理施肥能够增加土壤表层有机碳含量,有机/无机配施会使耕层以下土壤无机碳增加。%In this study, the Fukang Station for Desert Ecological garded as a platform to lucubrate the dynamic change of soil carbon Research, Chinese Academy Sciences, was re- content, soil carbon sequestration potential and long-term oasis agricultural nutrient cycling, including the distribution of soil inorganic carbon content (SIC) and organic carbon content (SOC) along soil profile and at different fertilization time under the different soil fertilization treatments, such as the treatment without fertilization (CK), single fertilizer application (NPK), and fertilization treatment with straw (S) in arid area. The results showed that the fertilizer application, soil depth and fertilization time affected significantly the SOC content and SIC content in soil (P 〈 0. 01 ). Compared with CK, the SOC con- tent and SIC content under NPK, M and S were significantly increased ( P 〈 0. 05 ) , and the SIC content under the organic/inorganic fertilizing combination (M) was significantly higher than that under chemical fertilizer applica- tion. The average SIC content was increased

  13. 长期定位施肥对石灰性紫色水稻土AMF多样性的影响%Effects of long-term fertilization on arbuscular mycorrhizal fungi community in calcareous purple paddy soil

    Institute of Scientific and Technical Information of China (English)

    辜运富; 李芳; 张小平; 涂仕华; KRISTINA Lindstr(o)m

    2012-01-01

    为了解长期定位施肥对石灰性紫色水稻土丛枝菌根真菌(AMF)物种多样性的影响,从稻麦轮作下连续26年定位施农家肥(M)、氮肥+农家肥(NM)、氮磷肥+农家肥(NPM)、氮磷钾肥+农家肥(NPKM)、不施肥(CK)、氮肥(N)、氮磷肥(NP)、氮磷钾肥(NPK)等不同施肥处理小区采集根区土样,分离鉴定AMF、测定多样性特征.共鉴定出17种AMF,其中球囊霉属Glomus 12种,占己分离总数的70.5%,为优势属;无梗囊霉属Acaulospora 3 种,占17.6%;原囊霉属Archaeospora和内养囊霉属Entrophospora各1种,各占5.9%.无论是石灰性紫色十种植水稻还是小麦,AMF侵染率最高的施肥处理均为无肥处理(CK),施肥特别是磷肥,降低AMF侵染率、孢子密度、相对多度和种丰度.变性梯度凝胶电泳(denaturing gradient gel electrophoresis,DGGE)分析结果表明,不施肥对照(CK)的AMF多样性最丰富,多样性指数最高,水稻和小麦种植下的多样性指数分别为2.68和3.02;与无机肥处理相比,农家肥配施无机肥提高了AMF多样性指数.农家肥配施无机肥更有利于AMF发育.%To determine the influence of long term fertilization on arbuscular mycorrhizal fungi (AMF) species diversity in calcareous purplish paddy soil, rhizosphere soil samples collected from different designed plots continuously supplied with manure only (M), nitrogen fertilizer plus manure (NM), nitrogen and phosphoric fertilizer plus manure (NPM), nitrogen, phosphoric and potassium fertilizer plus manure (NPKM), mineral nitrogen (N), nitrogen-phosphoric fertilizer (NP), nitrogen and phosphoric and potassium fertilizer (NPK) and without treatment (CK), under rice-wheat rotations for 26 years were mycologically investigated. The results showed that there are 17 species of AMF, among them, 12 species belong to Glomus, accounting for 70.5 percent of the total isolated species. Three species belong to Acaulospora, accounting for 17.6 percent of the isolated species

  14. [Effect of Long-Term Fertilization on Organic Nitrogen Functional Groups in Black Soil as Revealed by Synchrotron-Based X-Ray Absorption Near-Edge Structure Spectroscopy].

    Science.gov (United States)

    Li, Hui; Gao, Qiang; Wang, Shuai; Zhu, Ping; Zhang, Jin-jing; Zhao, Yi-dong

    2015-07-01

    Nitrogen (N) is a common limiting nutrient in crop production. The N content of soil has been used as an important soil fertility index. Organic N is the major form of N in soil. In most agricultural surface soils, more than 90% of total N occurs in organic forms. Therefore, understanding the compositional characteristics of soil organic N functional groups can provide the scientific basis for formulating the reasonable farmland management strategies. Synchrotron radiation soft X-ray absorption near-edge structure (N K-edge XANES) spectroscopy is the most powerful tool to characterize in situ organic N functional groups compositions in soil. However, to our most knowledge, no studies have been conducted to examine the organic N functional groups compositions of soil using N K-edge XANES spectroscopy under long-term fertilization practices. Based on a long-term field experiment (started in 1990) in a black soil (Gongzhuling, Northeast China), we investigated the differences in organic N functional groups compositions in bulk soil and clay-size soil fraction among fertilization patterns using synchrotron-based N K- edge XANES spectroscopy. Composite soil samples (0-20 cm) were collected in 2008. The present study included six treatments: farmland fallow (FALL), no-fertilization control (CK), chemical nitrogen, phosphorus, and potassium fertilization (NPK), NPK in combination with organic manure (NPKM), 1.5 times of NPKM (1.5 NPKM), and NPK in combination with maize straw (NPKS). The results showed that N K-edge XANES spectra of all the treatments under study exhibited characteristic absorption peaks in the ranges of 401.2-401.6 and 402.7-403.1 eV, which were assigned as amides/amine-N and pyrrole-N, respectively. These characteristic absorption peaks were more obvious in clay-size soil fraction than in bulk soil. The results obtained from the semi-quantitative analysis of N K-edge XANES spectra indicated that the relative proportion of amides/amine-N was the highest

  15. Long-term changes of soil fertility factors and their relationships with NDVI%长期土壤肥力因子变化及其与植被指数耦合关系

    Institute of Scientific and Technical Information of China (English)

    李燕丽; 潘贤章; 周睿; 王昌昆; 刘娅; 石荣杰; 陈冬峰; 赵其国

    2013-01-01

    以广西南宁、崇左地区作为典型区,利用AVHRR和MODIS NDVI遥感影像数据,以及1981年、2011年的土壤数据,分析归一化差异植被指数(NDVI)与土壤肥力因子及其变化之间的相互关系.结果表明:近30年来,土壤pH极显著下降,全氮、速效磷、速效钾含量显著上升;同时,NDVI变化整体呈现缓慢上升趋势,且NDVI变化与土壤有机质变化及土壤全氮变化呈显著正相关.因此,NDVI时间序列数据能够在一定程度上反映土壤有机质和土壤全氮含量的变化,这为土壤肥力长期变化监测提供了一种可行的方法.%Taking the Nanning and Chongzuo of Guangxi Province, South China as test areas, and by using the time-series NDVI of AVHRR and MODIS sensors and the soil data in 1981 and 2011, this paper analyzed the relationships between the normalized difference vegetation index (NDVI) and soil fertility factors, and the correlations between the long-term changes of the NDVI and soil fertility factors. In recent 30 years, the soil pH in test areas declined significantly, while the soil total nitrogen, available phosphorus, and available potassium contents had a significant increase. Meanwhile, the NDVI presented an overall slow-increasing trend, and the changes of the NDVI had significant positive relationships with those of the soil organic matter and total nitrogen, suggesting that the time-series NDVI could be used to indicate the changes of soil organic matter and total nitrogen to some extent, and hence, provide a feasible method for monitoring the long-term change of soil fertility.

  16. 长期施肥下我国南方典型农田土壤的酸化特征%Soil acidification characteristics in southern China s croplands under long-term fertilization

    Institute of Scientific and Technical Information of China (English)

    周晓阳; 徐明岗; 周世伟; Colinet Gilles

    2015-01-01

    [Objectives] The objective was to illustrate characteristics of soil acidification in southern China s croplands under long-term fertilization, which will help to reduce acidification rate in these areas by rational fertilization .[Methods]Soil acidification characteristics of typical croplands were evaluated using a 10-year monitoring data in 32 sites located in Hunan province , including paddy soils and red soils under the long-term fertilization .[Results]There is no obvious soil acidification in paddy soils , generally .Significant soil acidification is observed in the paddy-upland rotation with the acidification rate of 0.071 unit/a which is 10 times of that in the rice-rice succession cropping system .Soil acidification is mainly ascribed to the increase of chemical N fertilizer amounts in the paddy-upland rotation.Similarly, obvious soil acidification is also observed in red soils .Further, the acidification tendency with fertilization year consists of two different stages , stage Ⅰ, rapid decline in rate of soil acidification after the fertilization for 1-6 years, and Stage Ⅱ, slow decline or relatively stable in rate of soil acidification after the fertilization for 7-10 years.Additionally, more significant soil acidification ( average rate of 0.075 unit/a) is observed in red soils with initial higher pH (pH >6) than that with lower pH (pH 4-5), and there is a positive correlation between the soil acidification rate and application amounts of chemical nitrogen fertilizers.[Conclusions] In southern China s croplands the long-term chemical nitrogen fertilization accelerates soil acidification in paddy soils under the paddy -upland rotation and red soils with higher initial pH ( pH >6 ) . Therefore, controlling and reducing the application amounts of chemical nitrogen fertilizers is an effective measure for preventing further acidification in paddy -upland rotation soils and red soils .%[目的]阐明长期施肥下我国南方典型农田土壤的酸化

  17. The Soil Respiration Characteristics of Grey Desert Soil under Different Long - term Fertilization%长期不同施肥下新疆灰漠土土壤呼吸特征研究

    Institute of Scientific and Technical Information of China (English)

    许咏梅; 刘骅; 王西和

    2012-01-01

    [Objective ] The objective of this study was to demonstrate soil respiration characteristics of grey desert soil under different long - term fertilization in order to provide scientific basis for estimating carbon flux and carbon capacity of grey desert soil in northwest arid region of China. [Method] This long -term deferent fertilizer experiment last for 22 years. Five out of the twelve treatments were selected for this study. Soil respiration, rate was 24 hours continuous observation using ACE CO2 exchange instrument. The treatment included no fertilizer (CK) , applied nitrogen, phosphorus and potassium fertilizer (NPK) , applied livestock (M) , straws return (S) and combined application of organic manure and chemical fertilizer (NPKM). Air temperature and 5 cm soil surface temperature were monitored as well. [Result]For the five treatments, long -term application organic material (NPKM, M, S) had much higher soil respiration rate than no organic manure (CK, NPK). Especially M has significant impact on soil respiration rate, followed by S (straw return). Organic material was found to have smaller soil respiration rate at NPKM than M and S. This clearly exhibits that combination of manure and mineral fertilizer could mitigate C02 efflux from cropland. This finding is in agreement with the results of other authors. Sensitive analysis of relationship between soil respiration rate and ambient temperature showed that application of organic material, either M or S was more sensitive than no application organic material. Except for NPKM, the linear regression was shown between soil respiration rate and 5 cm surface temperature. [ Conclusion ] The results of the present study further support the idea that appropriate fertilizer management practices need to be developed for sustainable soil fertility promotion and environmental friendliness. Therefore, the existing fertilizer recommendations require revision for the farmland carbon sequestration and C02 efflux. Chemical

  18. Transformations of Fractions of Exogenous Chromium(Ⅲ)in Manural Loess Soil After Long- term Fertil-ization%长期不同施肥塿土对外源Cr(Ⅲ)形态转化的影响

    Institute of Scientific and Technical Information of China (English)

    李玉会; 张树兰; 封涌涛; 孙本华; 杨学云

    2014-01-01

    以23年长期不同施肥处理(不施肥CK,施氮磷钾化肥NPK,有机肥配合化肥MNPK)土壤为材料,外源添加浓度为500 mg·kg-1 Cr,经过90 d的室内培养,研究了土壤pH、有效态Cr及各个形态Cr含量随培养时间的变化。结果表明:外源添加Cr导致土壤pH下降了0.4~0.6个单位;施肥显著降低了土壤有效Cr含量,在培养结束后,NPK处理土壤有效态Cr较CK下降了约34%, MNPK处理土壤有效态Cr的含量几乎为零。长期施用NPK处理土壤铁锰氧化物结合态Cr和有机结合态Cr含量分别较CK提高了12%和38%,而可交换态Cr含量却较CK下降了约27%,但碳酸盐结合态和残渣态Cr含量与CK相比无显著差异;长期施用MNPK土壤可交换态、碳酸盐结合态、铁锰氧化物结合态Cr含量分别较NPK处理降低了100%、44%和29%,而有机结合态和残渣态Cr含量却分别提高了72%和17%。研究表明长期合理施肥,尤其是化肥配合有机肥施用可以显著提高塿土恢复力,降低塿土重金属Cr污染的危害。%Fractions and bioavailability of heavy metals in soils varied among different soils, thus impacting soil resilience to heavy metal contamination. We spiked two levels of Cr(Ⅲ)(0 and 500 mg·kg-1)to soils subjected to different fertilization for 23 years and incubated the soils for three months. The fertilizer treatments included(1)no fertilizer(CK),(2)mineral nitrogen, phosphate and potassium(NPK), and(3)organic manure integrated with NPK(MNPK). Soil Cr fractions were measured with sequential extraction. Spiking Cr decreased soil pH by 0.4 to 0.6 units. Long-term fertilization significantly reduced bioavailability of exogenous Cr. Compared with no fertilizer(CK), soil bioavailable Cr was 34% lower in NPK and almost 100% lower in MNPK. In NPK soil, iron and manganese oxides bounded and organic bounded fractions increased by 12%and 38%, respectively;exchangeable Cr contents decreased

  19. Characteristics of Black Soil Fertility and Comprehensive Assessment Under Long-term Fertilization%长期施肥下黑土肥力特征及综合评价

    Institute of Scientific and Technical Information of China (English)

    郝小雨; 周宝库; 马星竹; 高中超

    2015-01-01

    为探索黑土区耕地质量稳定提升、作物持续稳产高产的有效施肥模式,利用始于1979年的定位试验,研究了长期不同施肥措施对黑土物理性质(1项)、化学性质(8项)和生物肥力指标(4项)的影响,并运用主成分分析和聚类分析对其进行了综合评价。结果表明:长期施肥增加土壤养分含量,有机无机肥配施降低土壤容重。长期单施化肥导致土壤酸化,有机无机肥配施减缓土壤酸化。运用主成分分析对13个土壤肥力指标降维,提取到3个主成分,涵盖了原始数据信息总量的89.6%。系统聚类得到不同施肥措施的培肥效果为N2 P2 M2> NPKM 、NPM >M2、M >NPK、N2 P2>NP、CK ,有机肥与化肥配施为黑土最佳的培肥模式。综合评价培肥土壤、作物产量和环境效应,推荐常量化肥和有机肥配施(MNPK)为黑土最佳培肥模式。%In order to explore the effective fertilization mode to improve the cultivated land quality ,and crop con‐tinuous output ,based on long‐term experiment with various fertilizations in black soil of northeast China ,soil physical property (bulk density ) ,chemical properties (organic matter ,total nitrogen ,total phosphorus ,total potassium ,available nitrogen ,available phosphorus ,available potassium and pH ) ,and biological properties (dissolved organic carbon ,dissolved organic nitrogen ,soil microbial biomass carbon and soil microbial biomass nitrogen) were analyzed .Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used to evaluate these data .The results showed that long‐term fertilization could increase soil nutrient content , and compared with non‐fertilization and chemical fertilizer treatments ,combined application of organic manure and inorganic fertilizer reduced soil bulk density .Long‐term fertilization of chemical fertilizer could make the soil acidification ,and organic manure and

  20. Effects of Long-termed In-situ Fertilization on Wheat Rhizosphere Soil Nutrition in Chao Soil%潮土长期定位施肥对小麦根际土壤营养的影响

    Institute of Scientific and Technical Information of China (English)

    介晓磊; 杨先明; 刘世亮; 刘芳; 化党领; 李学军; 李宗军

    2011-01-01

    在长期定位施肥的基础上,采用盆栽试验,研究了不同施肥处理对冬小麦根际土壤与非根际土壤中pH、有机质含量及速效养分含量差异的影响.结果表明,(1)CK和PK处理在不同生育期其根际pH值均低于根外,土壤有机质含量逐渐下降.氮肥及和P、K配施的处理中,根际和非根际的pH值均低于PK和CK.N、NP、NPK处理的根际土壤有机质从拔节到成熟期有先下降后上升的趋势,而NK处理根际和非根际土壤有机质含量均逐渐下降.有机肥和化肥配施的处理中,在拔节期根际pH值均小于根外,在抽穗期和成熟期却相反,有机质含量从拔节期到成熟期均高于化肥处理.(2)CK和PK处理,土壤速效氮在各个时期均较其它处理低.长期施用氮肥和其它肥料配施(N、NP、NK、NPK)处理,在拔节期时,根际与非根际土壤的速效氮含量差异不明显,而根际的速效磷含量最高;到成熟期时,以N、NK处理的速效氮含量最高;偏施钾肥(NK和PK)处理的根际与非根际土壤速效钾含量变化不明显,但高于NPK处理;长期施用有机肥和NPK处理根际土速效氮含量较化肥处理高,以MNPK和1.5MNPK处理表现最明显.除SNPK外,各处理根际和非根际土速效磷含量均明显高于化肥处理,以1.5MNPK处理含量最高.%Based on a 15-year long-term fertilization experiment in Chao soil, the effects of different fertilization treatments on pH value, organic matter and available nutrition content in wheat rhizosphere soil and non-rhizosphere soil were studied by pot experiment. The results showed that: (1) The pH values of the CK and PK treatments were much lower in the rhizosphere soil than that in the bulk soil, and soil organic matter content was gradually declining. The pH values in rhizosphere soil and bulk soil of applied nitrogen fertilizer and combined with P, K treatments were less than those of PK and CK treatments. The soil organic matter contents of N, NP and NPK

  1. 长期施肥下黑土重金属的演变特征%Evolution Characteristics of Heavy Metals in the Black Soil Under Long-Term Fertilization

    Institute of Scientific and Technical Information of China (English)

    苏姝; 王颖; 刘景; 朱平; 高洪军; 张崇玉; 周世伟

    2015-01-01

    仍存在很大风险。%[Objective] It is necessary to assess the evolution of heavy metals in soils under long-term fertilization and cropping, which helps rational fertilization and healthy soils in the area.[Method]At a long-term Black Soil experimental station, Jilin, China, six treatments were selected in this study, including CK (control without fertilization), N (nitrogen), NP (nitrogen + phosphorus), NPK (nitrogen + phosphorus + potassium), NPKM (nitrogen + phosphorus + potassium + manure), and 1.5NPKM (1.5 times of NPKM). The soil in a 0-20 cm layer in each plot for each treatment was sampled in 1989, 1994, 2000, 2006, 2010, and 2012, respectively, and the total/available metal content (Cu, Zn, Pb, and Cd) was measured. Additionally, the metal activity index was also calculated.[Result] The results showed that the total and available metals (Cu, Zn, Pb, and Cd) did not change with the fertilization year in CK and those treatments receiving chemical fertilizers; except Pb significantly increased under manure application (NPKM and 1.5NPKM). However, Cd activity index decreased markedly by 27%-28% for manure treatments. Three stages in the evolution of soil metals with long-term manure application, attributed to the stage-by-stage change in the metal content of animal manure, were presented, that is, there was a slow increase between 1989 and 2000, a rapid increase between 2000 and 2010, and it kept steady or slowly decreased after 2010. For example, 0.03 mg·kg-1·a-1, 0.07 mg·kg-1·a-1, and -0.13 mg·kg-1·a-1, respectively, for total soil Cd in 1.5NPKM, and 0.11 mg·kg-1·a-1, 0.53 mg·kg-1·a-1, and -1.25 mg·kg-1·a-1, respectively, for available soil Cu in NPKM, were assessed in the three stages above mentioned. Further, a partial correlation analysis showed that the activity index of Cu, Zn, and Pb was positively related to Olsen-P, SOM, and negatively related to soil pH, respectively; whereas the Cd activity index was negatively related to Olsen-P and SOM and positively related to soil p

  2. LONG TERM COLLECTIONS

    CERN Multimedia

    STAFF ASSOCIATION

    2010-01-01

    ACKNOWLEDGMENTS The Long-Term Collections (CLT) committee would like to warmly thank its faithful donors who, year after year, support our actions all over the world. Without you, all this would not be possible. We would like to thank, in particular, the CERN Firemen’s Association who donated 5000 CHF in the spring thanks to the sale of their traditional calendar, and the generosity of the CERN community. A huge thank you to the firemen for their devotion to our cause. And thank you to all those who have opened their door, their heart, and their purses! Similarly, we warmly thank the CERN Yoga Club once again for its wonderful donation of 2000 CHF we recently received. We would also like to tell you that all our projects are running well. Just to remind you, we are currently supporting the activities of the «Réflexe-Partage» Association in Mali; the training centre of «Education et Développement» in Abomey, Benin; and the orphanage and ...

  3. Kinetics of K+ Adsorption and Desorption of Brown Soil Under Long-Term Fertilization%长期定位施肥对棕壤钾素吸附解吸动力学特征的影响

    Institute of Scientific and Technical Information of China (English)

    李娜; 韩立思; 吴正超; 王月; 兰宇; 韩晓日

    2012-01-01

    [Objective] The objective of study was to investigate the kinetics characteristics of K+ adsorption and desorption of brown soil under long-term (32 years) fertilization. [Method] Nine samples of different treatments were flowed through with deionized water as pretreatment. Miscible displacement techniques were used to study the adsorbing-desorbing process. [Result] The equilibrium time of adsorption ranged from 26 min to 65 min, and that of desorption ranged 65-130 min. The ranges of equilibrium adsorbing capacity and the equilibrium desorbing capacity were 7.40-19.44 cmolkg1 and 0.070-0.258 cmolkg1. The relation between velocity of potassium adsorbing and time could be described with the model of V=A+Blnt. There were correlation between parameters of adsorption and desorption were related with CEC, Clay, OM and available K in different degrees. First-order, Elovich, Parabolic diffusion and Dual constant were used to describe the kinetics of K adsorption and desorption of experimental soils. The results showed that Elovich and First-order were the best kinetic models for describing adsorption and desorption, respectively. [Conclusion] There were great different characteristics of adsorption and desorption under different fertilizations. The ability of adsorption could be increased by applying organic manure. And the ability of desorption improved with potassium rates. The effect of long-term fertilization on K+ adsorption and desorption kinetics of brown soil was up to the changes of physic-chemical properties of soil. There were different dynamic processes of potassium in soil under different fertilizations.%[目的]研究32年连续不同施肥对耕地棕壤K+吸附解吸动力学特征的影响.[方法]采用去离子水淋洗土壤,连续液流法研究9个不同施肥处理耕层土壤钾吸附解吸动力学特征.[结果]不同施肥处理土壤对K+吸附、解吸平衡时间变幅分别为26-65 min和65-130min;平衡吸附量和平

  4. Effects of enhancing soil organic carbon sequestration in the topsoil by fertilization on crop productivity and stability: Evidence from long-term experiments with wheat-maize cropping systems in China.

    Science.gov (United States)

    Zhang, Xubo; Sun, Nan; Wu, Lianhai; Xu, Minggang; Bingham, Ian J; Li, Zhongfang

    2016-08-15

    Although organic carbon sequestration in agricultural soils has been recommended as a 'win-win strategy' for mitigating climate change and ensuring food security, great uncertainty still remains in identifying the relationships between soil organic carbon (SOC) sequestration and crop productivity. Using data from 17 long-term experiments in China we determined the effects of fertilization strategies on SOC stocks at 0-20cm depth in the North, North East, North West and South. The impacts of changes in topsoil SOC stocks on the yield and yield stability of winter wheat (Triticum aestivum L.) and maize (Zea mays L.) were determined. Results showed that application of inorganic fertilizers (NPK) plus animal manure over 20-30years significantly increased SOC stocks to 20-cm depth by 32-87% whilst NPK plus wheat/maize straw application increased it by 26-38% compared to controls. The efficiency of SOC sequestration differed between regions with 7.4-13.1% of annual C input into the topsoil being retained as SOC over the study periods. In the northern regions, application of manure had little additional effect on yield compared to NPK over a wide range of topsoil SOC stocks (18->50MgCha(-1)). In the South, average yield from manure applied treatments was 2.5 times greater than that from NPK treatments. Moreover, the yield with NPK plus manure increased until SOC stocks (20-cm depth) increased to ~35MgCha(-1). In the northern regions, yield stability was not increased by application of NPK plus manure compared to NPK, whereas in the South there was a significant improvement. We conclude that manure application and straw incorporation could potentially lead to SOC sequestration in topsoil in China, but beneficial effects of this increase in SOC stocks to 20-cm depth on crop yield and yield stability may only be achieved in the South.

  5. Impact of long-term different fertilization on yellow brownish paddy soil carbon sequestration rate and organic carbon fractions%长期施肥对黄棕壤固碳速率及有机碳组分影响

    Institute of Scientific and Technical Information of China (English)

    陈云峰; 韩雪梅; 胡诚; 李双来; 乔艳; 刘东海

    2013-01-01

    Impact of long-term application of chemical fertilizer (NPK), manure (M), chemical fertilizer plus manure (MNPK) on yellow brownish paddy soil carbon sequestration rate (CSR) and organic carbon chemical fractions were explored based on a 31 years long-term experiment station. The plot of no fertilizer input was regard as the control (CK). CSR was estimated from data collected in 1985, 2002 and 2010. Organic carbon fractions that includes total organic carbon (TOC), microbial biomass carbon (MBC), labile carbon (LC) and recalcitrant carbon (RC) were measured in the wheat/middle-rice rotation season of 2010 and 2011. Moreover, recalcitrant index (RI) and microbial quotient (MQ) were used to evaluate stability of organic carbon. The results showed that the CSR among the three period of 1985—2002, 2002—2010, 1985—2010 were different irrespective of fertilization treatments. The CSR of MNPK in the three period were 512, 1 132, 711 kg·hm-2·a-1, respectively. Correspondingly, the CSR of M were 627, 528, 595 kg·hm-2·a-1, NPK were 141, -50, 80 kg·hm-2·a-1. Fertilization improved TOC, RC, LC and MBC with the rank of MNPK>M>NPK>CK and occasionally MNPK>M>NPK>CK. Fertilization decreased RI and the RI of MNPK was the lowest among the three fertilization treatments. The mean RI of four sampling times of MNPK was lower 7.3% than that of CK. M and MNPK significantly increased the MQ compared to that of CK. In conclusion, fertilization increased the capacity of carbon sequestration and the stability of organic carbon as well as the contribution of labile carbon to total organic carbon. Of the three fertilization treatments, MNPK had the best positive effects on soil carbon sequestration and organic stabilization, followed by M, and NPK.%  依托长江中下游黄棕壤稻麦轮作区31年长期定位试验,以不施肥为对照(CK),研究施用化肥(NPK)、有机肥(M)及有机肥—化肥(MNPK)对土壤固碳速率、总有机碳及其组成(难降

  6. A Research on Response of Enzyme Activities to Long-term Fertilization in Lime Concretion Black Soil%淮北砂姜黑土酶活性对长期不同施肥模式的响应

    Institute of Scientific and Technical Information of China (English)

    陈欢; 李玮; 张存岭; 乔玉强; 杜世州; 赵竹; 曹承富

    2014-01-01

    同。【结论】同等施氮水平下,有机肥与化肥配施与单施化肥或单施有机肥相比,能使砂姜黑土脲酶、磷酸酶、过氧化氢酶及蔗糖酶均保持较高的活性,有利于改善土壤生物化学环境,进而提高土壤可持续生产力;土壤酶之间相关关系各有不同,呈显著正相关关系的有脲酶与过氧化氢酶、脲酶与蔗糖酶及过氧化氢酶与蔗糖酶,而磷酸酶与其他3种酶之间均呈显著负相关关系;砂姜黑土酶活性受季节影响的程度因酶种类与施肥方式不同而有所不同。%[Objective]In order to provide a theoretical support for improving soil biochemical environment and soil quality, insuring high and steady yield of crops in view of the characters of“drought, waterlogging, concretion, leanness”in lime concretion black soil, the responsive mechanism of soil enzyme activities to fertilization in black soil was studied by the way of exploring effects of long-term fertilization on soil enzyme activities. [Method] Based on a 31 yeas long-term fertilization experiment in Yangliu of Anhui province, the change trend of activities of urease, acid phosphatase, neutral phosphatase, catalase and invertase in tilth soil (0-20 cm) was investigated with 5 patterns of fertilization (non-fertilization, application of single chemical fertilizer, application of single organic fertilizer, mixed application of organic and chemical fertilizer (with the same amount of nitrogen), mixed application of organic and chemical fertilizer (with the lager amount of nitrogen) in wheat-maize rotation system, as well as the correlation and paired comparison was analyzed to interpret the relationship among soil enzymes and seasonal variation, respectively.[Result]Compared with control, the activities of urease, catalase, and invertase increased significantly by 130.5%and 129.5%, 11.4% and 14.9%, and 31.4% and 12.0%, respectively, after wheat and maize harvested in the situation of

  7. Dissimilar response of plant and soil biota communities to long-term nutrient adition in grasslands

    NARCIS (Netherlands)

    Wal, van der A.; Geerts, R.H.E.M.; Korevaar, H.; Schouten, A.J.; Jagers op Akkerhuis, G.A.J.M.; Rutgers, M.; Mulder, C.

    2009-01-01

    The long-term effect of fertilizers on plant diversity and productivity is well known, but long-term effects on soil biota communities have received relatively little attention. Here, we used an exceptional long-lasting (>40 years) grassland fertilization experiment to investigate the long-term e

  8. 长期不同施肥处理对栗褐土可培养微生物数量的影响%Effects of long-term different fertilization on culturable microorganisms quantity in cinnamon soil

    Institute of Scientific and Technical Information of China (English)

    杨艳菊; 王改兰; 张海鹏; 赵旭; 熊静; 黄学芳

    2013-01-01

    The effects of long-term fertilization on soil microorganism populations and their quantity and the correlation between microorganism and available nutrients basis in cinnamon soil were studied in this paper.The results showed that bacterial was the main microorganism in cinnamon soil with the proportion of 92.72% ~95.91%.Organic fertilizer could significantly increase the quantity of soil microorganism for bacteria quantity of M1 N,actinomycetes quantity of M1 NP,fungi quantity of M2NP were the highest of all treatments and the bacteria quantity difference of M1N compared with the control was significant.The quantity of phosphate-solubilizing bacteria also could be significantly increased under the conditions of using organic fertilizer.The correlations between bacteria,fungi,actinomycetes and inorganic phosphate-solubilizing bacteria with available nitrogen,available phosphorus and available potassium were in significant level.%在24年长期定位试验的基础上,以选择性培养基为基础研究长期定位施肥对土壤微生物种群及数量的影响,同时测定了土壤速效养分的含量,探讨了微生物与土壤速效养分的相关关系.结果表明,栗褐土微生物以细菌为主体,约占微生物总数的92.72% ~95.91%;施用有机肥可以显著提高土壤微生物的数量,处理M1N细菌数量最多,显著高于对照;处理M1NP放线菌数量最多,处理M2NP真菌数量最多;施用有机肥可以显著提高土壤解磷细菌数量;细菌、真菌、放线菌和无机磷细菌与碱解氮、速效磷和速效钾相关性均达显著或极显著水平.

  9. Effect of Long-Term Fertilization on Pb, As Contents of Soil and Maize Grain%长期施肥对土壤及玉米籽粒中Pb、As含量的影响

    Institute of Scientific and Technical Information of China (English)

    杨振兴; 周怀平; 解文艳; 关春林; 车丽

    2015-01-01

    Objective] The objective of this study is to explore the dynamic changes on contents of heavy metal Pb, As in cinnamon soil of long-term fertilization.[Method]Based on the experiment on 22-year application of nitrogen, phosphorus and organic fertilizers and the analysis of Pb and As contents in 0-20 and 20-40 cm soil layers and maize grains in 2013, the effects of accumulation state, interannual variation characteristics and profile distribution on changes of Pb and As contents in cinnamon soil and maize grains after long-term fertilization were studied.[Result]The soil Pb and As contents of no fertilizer treatment decreased, others increased. The soil Pb content increased 1.77-8.41 mg·kg-1and variation of Pb was between 4.42% and 20.95%, respectively, as compared to the baseline levels. The soil As content decreased 17.10%-41.54%, respectively, as compared to the baseline levels. The content of Pb has obvious properties of surface-accumulation. The content of As in 20-40 cm soil layer was more than that in the plough layer. The contents of two heavy metals in soil tested in 2013 did not exceed the upper limits of the grade II criteria of the Environment Quality Standard for Soil. Pb and As contents in cinnamon soil were not significantly affected by the use of phosphate and organic fertilizers among treatments. Pb and As contents in maize grains analyzed in 2013 were below their respective thresholds of the national food safety standard.[Conclusion]The accumulation of heavy metal Pb in fertilization treatments was demonstrated. So, more attention should be paid to control the amount of fertilizer application.%【目的】探究褐土区长期施肥农田土壤重金属Pb、As含量的动态变化规律。【方法】基于22年的氮磷化肥与有机肥配施长期定位试验,通过对0—20及20—40 cm土层及2013年玉米籽粒Pb、As含量的测定,分析褐土农田Pb、As的累积状况、年际变化特征、剖面分布特征及对玉米籽粒Pb

  10. Long-term urethral catheterisation.

    Science.gov (United States)

    Turner, Bruce; Dickens, Nicola

    This article discusses long-term urethral catheterisation, focusing on the relevant anatomy and physiology, indications for the procedure, catheter selection and catheter care. It is important that nurses have a good working knowledge of long-term catheterisation as the need for this intervention will increase with the rise in chronic health conditions and the ageing population.

  11. 大麦长期肥料效率和土壤养分平衡%Fertilizer Efficiency and Soil Apparent Nutrient Balance for Barley under Long-Term Fertilization

    Institute of Scientific and Technical Information of China (English)

    唐旭; 陈义; 吴春艳; 杨生茂; 刘玉学; 吕豪豪; 马义兵; 李菊梅

    2013-01-01

    In the 19-year located fertilization experiment in barley,five treatments were designed with different combinations of nitrogen (N),phosphorus (P),and potassium (K) fertilizers.The natural productivities of nutrient elements from soil and environment,fertilizer efficiencies and soil nutrient apparent balances were investigated by measuring aboveground biomass,grain yield,and nutrient contents in grain and straw.Under no fertilization condition,the amounts of nutrient supply from soil and environment were 44.5,10.7,and 52.5 kg ha-1 for N,P,and K elements,respectively.The average N,P,and K contents were 17.30,3.48,and 4.18 g kg-1 in grain and 4.85,0.64,and 17.50 g kg-1 in straw,respectively.The percentages of nutrient elements translocated from aboveground organs into grain were 75.7% forN,83.5% for P and 18.8% for K.This result indicated that the most of N and P absorbed by plant were ultimately deposited into grains,whereas more than 80% K absorbed remained in straws.For producing 1000 kg grain,barley plant required absorptions of 22.3 kg N,4.0 kg P,and 20.5 kg K.Clearly,the P requirement was 5-6 times the requirement of N or K.The average apparent fertilizer use efficiencies for N,P,and K fertilizers were 29.0%,12.8%,and 71.8%,respectively.The average accumulative recovery efficiencies of N,P,and K over 19 years were 75.3%,63.6%,and 203.2%,respectively.Under balanced fertilization with fixed N,P and K inputs,there were annual net gains of 18.4 kg ha-1 for N and 6.9 kg ha-1 for P,but a net loss of 43.8 kg ha-1 for K in soil.Such soil condition produced barley yield of 2350 kg ha-1 per year.%基于19年田间定位试验,通过测定氮、磷、钾肥不同配施处理下,大麦地上部生物量、产量及籽粒和秸秆中各养分含量,研究了大麦生长期土壤和环境养分供应状况、肥料效率和土壤养分表观平衡.结果表明,不施肥条件下,平均每年大麦可从土壤和环境中吸收氮、磷和钾素44.5、10

  12. 长期定位施肥对石灰性紫色水稻土古菌群落结构的影响%Effect of long-term fertilization on archaeal community structure in calcareous purplish paddy soil

    Institute of Scientific and Technical Information of China (English)

    辜运富; 张小平; 涂仕华; Kristina Lindstr(o)m

    2011-01-01

    manure (NPKM), without fertilization (CK), mineral nitrogen (N), nitrogen-phosphorus (NP) and nitrogen, and phosphorus and potassium (NPK). Our results showed that long-term fertilization significantly affected soil archaeal community structure; the richness and diversity of archaeal community under NM, NP and NPKM were lower than those under the other fertilization treatments (M,NPM, CK, N, and NPK). Based on the DGGE patterns, two soil DNA samples isolated from the NPK-amended soil were used for RFLP analysis of archaea. Phylogenetic analyses showed that archaea in the calcareous purplish paddy soil was highly diverse, and the sequences were closely related to those archaeal sequences isolated from various soils and water environment. Cluster analysis of the DGGE profiles showed that archaeal communities under the eight fertilization treatments clustered into three groups. In soil from paddies currently under rice cultivation, the archaeal communities in the soil amended with M and NPK grouped into the first cluster, while NP was in the second group, and NPKM, NM, CK, N and NPM were in the third. In the soil with wheat cultivation, NP-treated archaeal communities clustered into a cluster, NPKM and M were in the second cluster, and N, NPK, NM, NPM and CK soil communities comprised the third cluster. The cluster analysis showed that crop type impacts the community structure of soil archaea.

  13. Characteristics of soil C02 emission and carbon balance under long-term fertilization in red soil%长期施肥下红壤旱地土壤CO_2排放及碳平衡特征

    Institute of Scientific and Technical Information of China (English)

    黄晶; 李冬初; 刘淑军; 刘宏斌; 王伯仁

    2012-01-01

    Diurnal variation of soil respiration affected by fertilization was investigated with the static dark chamber method and gas chromatograph technique at the long-term experiment in red soil, and the contribution of root respiration was detected by root exclusion method. Net ecosystem productirity(NEP) was calculated for estimating carbon sequestration intensity. The results show that there are significant seasonal variations of the soil respiration rate and bulk respiration rate as the crop growth and temperature raise in wheat and maize growth seasons in all treatments. The accumulation amount of soil respiration and bulk respiration in the maize growth season is greater than that in the wheat growth season. The accumulation amount of soil respiration and bulk respiration of the NPKMtreatment is the largest in the wheat and maize growth seasons, and is higher than those of the other treatments significantly (P 〈 0. 05). The accumulation amounts of soil respiration and bulk respiration of the NP and NPK treatments are the second, and those of the CK and NK treatments are minimum. The mean ratios of root respiration to total soil respiration in the wheat growth seasons and maize growth seasons are 7.6%-17.4% and 4.7%- 16.6%, and the contribution ratio of rhizospheric respiration of the NPKM treatment is largest in all treatments. Soils are sinks of atmospheric CO2 under the NPKM and CK treatments. Compared to other treatments, inorganic fertilizer combination (NPKM) has a stronger carbon sink function, therefore the NPKM is reasonable fertilization in red soil.%在国家肥力网红壤旱地长期定位试验地上,采用静态箱/气相色谱法测定土壤CO2排放速率,同时利用根去除法区分根系对土壤呼吸的贡献,通过计算净生态系统生产力(NEP),判断长期不同施肥下红壤旱地农田碳汇强度。结果表明,小麦、玉米生长季各处理的土壤和土体呼吸速率随着作物生长、温度升高均呈

  14. Effects of Long-term Fertilization on Enzyme Activities and Soil Fertility for Black Farmlands Under Different Soil Matter Levels%长期施肥对不同有机质含量农田黑土土壤酶活性及土壤肥力的影响

    Institute of Scientific and Technical Information of China (English)

    陈文婷; 付岩梅; 隋跃宇; 刘晓冰; 李建维

    2013-01-01

    The research investigated the effects of long-term fertilization on soil enzyme activities and soil fertility for the black farmlands under different soil organic matter levels. This study used the conventional analysis methods to test and analyze the activity of soil urease, phosphatase, invertase, protease and the contents of soil organic matter, total nitrogen, total phosphorus, available nitrogen, available phosphorus in five black farmlands soil with different soil matter content of soil spatial shift long-term experiments in National Observation Station of Hailun Agro-ecology System. The results showed that, the application of chemical fertilizers could increase the nutrient content in different degree and soil enzyme activities of black soil. The order of the raise was Bei'an (SOM11)>Nenjiang (SOM6)>Helen (SOM5)>Dehui (SOM3) > Lishu (SOM1.7). Compared to other four soils, Bei'an (SOM11) reached significant difference level(P嫩江(SOM6)>海伦(SOM5)>德惠(SOM3)>梨树(SOM1.7),北安黑土与其他4种土壤之间达到了差异显著水平(P<0.05)。相关分析结果显示:土壤脲酶、磷酸酶、蛋白酶、蔗糖酶与土壤有机质、全氮、全磷、碱解氮显著相关,土壤脲酶、蔗糖酶可以反映不同有机质含量农田黑土长期施肥后土壤质量变化趋势。

  15. Competição de adubos fosfatados no algodoeiro, em ensaio de longa duração Phosphate fertilizers competition in a long term experiment with cotton, on a dusky red latosol

    Directory of Open Access Journals (Sweden)

    Nelson Machado da Silva

    1987-01-01

    consecutive applications of fertilizer mixtures containing P with or without S, in a long term trial conducted with cotton, on an acid and low-fertility Dusky Red Latosol, velvet bean (Stizolobium atterrimum Piper & Tracy was cultivated and limestone enough to attain the soil pH around 6.2, was applied. During the next five years, from 1978 to 1983, IAC 18 cotton cultivar was grown with the same fertilization of the initial phase of study. N and K were supplied in constant dosis, and P and S in variable dosis, through the combination of ammonium sulfate, nitrochalk, ordinary superphosphate, triple superphosphate and potassium chloride. Sulfur deficiency symptoms such as the appearance of yellow leaves at the top of plants ("lemon green" occurred from fifth year on, in the plots which received no S, in accordance with a tendency of increasing yield. However, only after acidity correction, it was possible to maintain high cotton yield and to obtain differences statistically significant between fertilizer mixtures with or without S. In the last five-year period, annual application of 50 and 100 kg/ha of P2O5 increased cotton yield, respectivelly of 37 and 40%, as triple superphosphate and of 55 to 67%, in the case of ordinary superphosphate. With regard to economical aspects, boll weight and fiber length, ordinary superphosphate was also superior. The use of additional doses of S (120 kg/ha however, did not improve the performance of cotton fertilized with 60 kg/ha of S. It was proposed that S should be incorporated in commercial fertilizer mixtures.

  16. Potassium availability in a hapludalf soil under long term fertilization Disponibilidade de potássio em argissolo com histórico de adubação

    Directory of Open Access Journals (Sweden)

    João Kaminski

    2010-06-01

    Full Text Available In a system in which fertilization is recommended, diagnosis of soil K availability and the establishment of critical levels are made difficult by the possibility of a contribution of non-exchangeable forms of K for plant nutrition. Due to its magnitude, this contribution is well diagnosed in long term experiments and in those which compare fertilization systems with positive and negative balances in terms of replacement of the K extracted by plants. The objective of this study was to evaluate K availability in a Hapludalf under fertilization for sixteen years with the addition of K doses. The study was undertaken in an experiment set up in 1991 and carried out until 2007 in the experimental area of the Soil Department of the Federal University of Santa Maria (Universidade Federal de Santa Maria - UFSM, in Santa Maria (RS, Brazil. The soil was a Typic Hapludalf submitted to four doses of K (0, 60, 120 and 180 kg ha-1 K2O and subdivided in the second year, when 60 kg ha-1 of K2O were reapplied in the subplots in 0, 1, 2 and 3 times. As of the fifth year, the procedure was repeated. Grain yield above ground dry matter and total K content contained in the plant tissue were evaluated. Soil samples were collected, oven dried, ground, passed through a sieve and submitted to exchangeable K analysis by the Mehlich-1 extractor; non-exchangeable K by boiling HNO3 1 mol L-1 and total K by HF digestion. Potassium fertilization guidelines should foresee the establishment of a critical level as of which the recommended dose should accompany crop needs, which coincides with the quantity exported by the grain, without there being the need for the creation of broad ranges of K availability to predict K fertilization. In adopting the K fertilization recommendations proposed in this manner, there will not be K translocation in the soil profile.Em um sistema de recomendação de adubação, o diagnóstico da disponibilidade de K do solo e o estabelecimento de n

  17. Scenario Analysis on Effects of Long-term Fertilization on Soil Carbon and Nitrogen Codependency%长期定位施肥对土壤的碳氮共济效应情景分析

    Institute of Scientific and Technical Information of China (English)

    雷宝坤; 刘宏斌; 陈安强; 毛妍婷; 续勇波

    2014-01-01

    The term of carbon (C) and nitrogen (N) codependency, reflecting the relation of mutual dependence, co-transformation and cooperation, is regarded as active factors for improving soil quality, which differs it from the passive couple mechanism for discussing the soil C and N relationship. There was an interrelation of mutual dependence and interaction between C and N in soil. What quantity and composition of soil C and N could facilitate the codependency of C and N? How much soil N could be sustained by soil C? These problems deserve further consideration. The paper analysed the change in soil C and N concentrations, effects of fertilization on the soilw(C)/w(N) ratio, soil capacity of conserving N by C, the relationship of soil C and N codependency and its scenario analysis by data mining the long-term fertilization experiment results to explore the biologic potential of soil C and N, improve soil productivity, environment and balanced cycling of soil C and N. By searching literature database, we obtained about 1782 long-term fertilization data on carbon and nitrogen in China soil from 69 representative articles. Results from analyzing these data sets indicated that the correlation between organic C and total N could be expressed by the functionyC=7.66xN+1.8162 (r2=0.734**,n=737). The mean concentrations of total N and organic C were 1.17 g⋅kg-1 and 10.8 g⋅kg-1, and ranged from 0.08 g⋅kg-1 to 3.52 g⋅kg-1 and from 0.64 g⋅kg-1 to 32.08 g⋅kg-1, respectively. Carbon to nitrogen ratio (w(C)/w(N)) concentrated on the range from 7.6 to 10.7, accounting for 80% of the total samples. It was helpful to increasew(C)/w(N) through fertilizing inorganic and organic fertilizer together. Solely fertilizing synthesized fertilizers, especially only one fertilizer, decreasedw(C)/w(N) significantly. Under the scenario of the storage rate of 20 kg N·hm-2·a-1 and the targetw(C)/w(N) of 9, 10 and 11, the soil samples of carbon saturation accounted for 52.7%, 72.1% and 87

  18. 长期施肥下水稻土有机碳固持形态与特征%Characteristics of Organic Carbon Stabilization in Paddy Soil Under Long-term Different Fertilization

    Institute of Scientific and Technical Information of China (English)

    徐香茹; 蔡岸冬; 徐明岗; 汪景宽; 张文菊

    2015-01-01

    Understanding the mechanisms of soil organic carbon(SOC)stabilization would help improve soil carbon sequestration in paddy soil. In this paper, we obtained paddy soils from a 30 year experimental field under five different fertilization, including no fertilizer(con-trol), mineral nitrogen(N)-phosphorus(P)-potassium(K)fertilizers(NPK), 70%mineral N+30%organic N plus PK(NPKM7/3), 50%mineral N+50%organic N plus PK(NPKM5/5), and 30%mineral N+70%organic N plus PK(NPKM3/7). Organic N was provided from green manure and pig manure. The soils were subjected to separating unprotected, and physically, chemically, bio-chemically, physical-chemically, and physical-biochemically protected SOC fractions by a physical-chemical combined fractionation method. Except the unpro-tected light fraction and the occluded silt and clay-sized fraction, the mass proportion of all other SOC factions was significantly different be-tween the treatments. Compared with non-fertilization(CK)treatment, chemical fertilizers mixed with organic manure(NPKM7/3、NPKM5/5 and NPKM3/7)significantly increased the content of total SOC(19.1~25.0 g·kg-1), unprotected coarse particulate organic carbon(cPOM) (8.41~12.7 g·kg-1), and physically protected aggregate(μagg)organic carbon(6.41~6.62 g·kg-1)in red paddy soil(P﹤0.05). There were no significant differences for the chemically, biochemically, physical-chemically and physical-biochemically protected fractions between the five treatments. These results indicated that the unprotected cPOM and the physically protected μagg fractions were the most sensitive ones in long-term fertilization. There was a linear positive correlation between total SOC and tcPOM, physically protected μagg, and oc-cluded POM inside theμagg(iPOM)fraction(P﹤0.05), and their response efficiency to total SOC accumulation(the slope of the regression) was 0.5, 0.12, and 0.12 respectively. However, the response efficiency of non-hydrolysis clay and physic-chemically protected silt

  19. 长期施肥红壤钾素在有机无机复合体中的分布%Distribution of potassium in the organo-mineral complexes of red soils under long-term fertilization

    Institute of Scientific and Technical Information of China (English)

    岳龙凯; 蔡泽江; 徐明岗; 王伯仁; 黄庆海; 李冬初; 柳开楼; 李建军; 张会民

    2015-01-01

    生长的主要钾源,其中<2 μm粒级复合体中交换性钾、非交换性钾含量与产量之间均存在显著正相关关系( P<0.05 ). [结论] <2 μm粒级复合体是土壤钾素的主要贮存库. 在长期不施钾肥条件下土壤<2 μm粒级复合体中交换性钾和非交换性钾含量降低,施钾有利于该粒级复合体中交换性钾和非交换性钾积累. 旱地红壤<2、2 10及10 50 μm粒级复合体钾素含量高,且与产量之间存在显著的正相关关系,是植物钾素主要供源.%[Objectives] Soil organo-mineral complexes contain most of soil nutrients that have become a most important part of soil nutrients .Change of soil potassium contents affects the contents of potassium in different sizes of organo-mineral complex .So long-term experiments of red soil started from 1990 ( Qiyang ) and 1986 ( Jinxian ) were carried out to investigate distribution of exchangeable , non-exchangeable and total potassium ( K) in different sizes of organo-mineral complex .[Methods] The soil samples of 0-20 cm depth were collected from the four treatments in the long term experiment at both sites:No fertilization ( CK) , mixed application of chemical nitrogen and phosphorus fertilizer ( NP ) , mixed application of NP combined with chemical potassium fertilizer ( NPK ) , mixed application of NPK combined with manure ( NPKM ) treatments. Stokes law was used to calculate sedimentation rates of different sizes of organo-mineral complex which were separated using siphon .The soil exchangeable, non-exchangeable and total potassium were determined .[Results] In the two sites, 96.4%-98.9%of the exchangeable K , 87.9%-96.7%of the non-exchangeable K and 95.1%-96.1%of the total K are in 0-50 μm sizes of organo-mineral complex .Especially , 76.3%-92.3% of the exchangeable K , 45.8%-73.7%of the non-exchangeable K and 49.4%-70.6% of the total K at both sites are mainly in <2 μm size complex.Comparing with CK, the contents of non-exchangeable K under NP are decreased by 5.4 to 8

  20. Effect of Long-term Different Fertilization Ways on Soil Enzyme Activities and Fertility in Dryland Black Humus Soil in the Loess Plateau%长期不同施肥方式对黄土高原旱地黑垆土土壤酶活性及其肥力的影响

    Institute of Scientific and Technical Information of China (English)

    张平良; 王淑英; 姜小凤; 苏敏; 李倩

    2009-01-01

    以30 a(1979~2008)肥料长期定位试验为基础,分析探讨长期不同施肥方式对旱地黑垆土耕层(0~20 cm)土壤酶活性及其肥力的影响.结果表明:土壤脲酶活性M处理显著高于其他处理,MNP和SNP处理效果优于NP处理;土壤多酚氧化酶活性N和NP处理增加效果显著,M、MNP、SNP处理效果均不明显;土壤蛋白酶活性N处理效果最佳,显著高于其他处理;MNP、SNP处理能显著增加土壤有机质和全磷含量,有利于全氮含量的积累,表明有机-无机肥配施是旱地中低产田培肥土壤的有效措施.%By a 30-year (1979~2008) long-term located fertilizer experiment, effect of long-term different fertilization ways on soil enzyme activities and fertility in dryland black humus soil was analyzed. The results showed that, effect of M treatment generate on soil urease activity is obviously higher than other treatments, and the effect of MNP and SNP treatments generate surpass that of NP treatment; The effect of N and NP treatments generate increasing on soil polyphenoloxidase activity is remarkable, and effect of M, MNP and SNP treatments generate is not to be obvious. The effect of N treatment way on soil protein enzyme activity is very best, which obviously is higher than others; MNP and SNP treatments can obviously increase soil organic and total phosphorus contents, which is advantage to accumulate total nitrogen content, which indicated that organic-inorganic matches executes is a effective measure of the cultivating soil fertility in dryland of middle-low yielding.

  1. 宁远县耕地地力变化状况与施肥效益的长期定位监测研究%Long-term Located Monitoring in Fertility Variation and Fertilizing Effects of Cultivated Land in Ningyuan County

    Institute of Scientific and Technical Information of China (English)

    蒋毛庚; 柏小勇; 胡萍翠; 陈志翠

    2011-01-01

    总结分析了1999~2007年宁远县水稻土的土壤肥力监测、肥力试验及农户施肥效果.结果表明:9a间土壤中有机质平均含量下降1g/kg,不同土种区域有机质含量变化差异较大,浅黄泥等土种有机质含量平均上升了5.1g/kg,河沙泥等土种减少了4.7g/kg;监测区域内约有25.6%的耕地肥力水平逐年上升,有53.3%的耕地土壤肥力呈下降的趋势;长期不施任何肥料情况下,地力产量为施肥区的64.3%,并且产量有下降的趋势,不施肥严重影响作物产量的提高;30%有机肥与70%无机肥的配合施用为最佳配施比例.最后撤道了利用该监测成果指导全县大面积的配方施肥和农作物秸秆还田所取得的成效.%The results of monitoring and experiment of rice soil fertility and fertilizing effects of farmer in Ningyuan County in 1999~2007 were summarized and analyzed.The results indicated that the average content of organic matters in soil decreased 1 g/kg; the content of organic matters in different soil types changed significantly, in which, the content of organic mauers in six soil types (shallow yellow mud, etc.) averagely increased 5.1 g/kg, and that in five soil types (river sediment, etc.) averagely decreased 4.7 g/kg; within the monitoring area, 25.6% of cultivated land fertility increased year by year, and 53.5% of cultivated land fertility showed decreasing trend; under the condition that non fertilizer application for a long-term, the capability yield in this area was the 64.3% of that in fertilizer application area.and the yield had decreasing trend, therefore, non fertilizer application will seriously impact the increase of crop yield; 30% of organic fertilizer combined applying with 70% of inorganic fertilizer is the optirmum formula for fertilizing.In the end, the strategy that using this monitoring results to enhance soil fertility and the achievements that using this monitoring results to guide formula fertilizing in

  2. Simple models and concepts as tools for the study of sustained soil productivity in long-term experiments. I. New soil organic matter and residual effect of P from fertilizers and farmyard manure in Kabete, Kenya

    NARCIS (Netherlands)

    Janssen, B.H.

    2011-01-01

    The rough outcomes of a long-term experiment in Kenya were (re-)interpreted using simple models to find causes of success or failure with regard to sustained soil productivity. A two- pools model calculated the development of soil organic matter, and a practical equation estimated the residual

  3. 长期不同施肥对(土娄)土团聚体胶结剂的影响%Effects of long-term fertilization regimes on changes of aggregate cementing agent of Lou Soil

    Institute of Scientific and Technical Information of China (English)

    薛彦飞; 薛文; 张树兰; 杨学云

    2015-01-01

    密度以及游离氧化铝含量,但是六碳糖、碳酸钙、粘粒、游离氧化铁含量与CK没有差N. 长期不施氮或不施磷处理与CK相比,土壤五碳糖、六碳糖、碳酸钙以及游离氧化铁的含量显著提高,但游离氧化铝含量显著降低,而对菌丝和粘粒含量没有影响. 不同团聚体胶结剂与团聚体平均重量直径的线性相关分析表明,机械稳定性团聚体平均重量直径与碳酸钙含量呈极显著正相关、与游离氧化铁显著正相关,与五碳糖和六碳糖极显著负相关. 水稳性团聚体平均重量直径分别与菌丝密度、 碳酸钙极显著正相关,与游离氧化铁显著正相关,与五碳糖达显著负相关. [结论]团聚体胶结剂与平均重量直径的多元逐步回归分析表明,碳酸钙是影响(土娄)土团聚体稳定性唯一显著的胶结剂.%[Objectives] Soil aggregate is a basic unit of soil structure , its formation and stability is mainly related to soil cementation of various cementing agent which is affected by soil management regimes .Fertilization practice , as one of soil management regimes has an important effect on aggregate cementing agent due to different input levels and subsequent effects on crop production .This study investigated effects of different fertilization regimes on aggregate cementing agent and was to thereby understand mechanism of formation and distribution of aggregates in Lou soil based on a long-term experiment under winter wheat and summer maize cropping system in Guanzhong Plain, Shaanxi province , China.[Methods] Different fertilization regimes included control ( CK, no nutrient input), nitrogen only (N), nitrogen and potassium (NK), phosphorus and potassium (PK), NP, NPK and straw plus NPK ( SNPK) and two levels of manure plus NPK ( M1NPK and M2NPK), totally nine treatments.The determination of aggregate cementing agents included fungal hyphal density , pentose , hexose , calcium carbonate , clay, free iron oxide and

  4. 长期不同施肥下红壤性水稻土综合肥力评价及其效应%Assessment and effects of integrated soil fertility in red paddy soil under different long-term fertilization

    Institute of Scientific and Technical Information of China (English)

    包耀贤; 黄庆海; 徐明岗; 于寒青

    2013-01-01

    以江西进贤红壤性水稻土长期试验为基础,运用模糊数学及统计学方法进行土壤肥力综合评价及其效应研究,以期达到土壤培肥的目的.结果表明,有机质、速效氮、速效磷、速效钾、物理性粘粒、团聚度和团聚体稳定率为研究区土壤肥力评价最小数据集,由其所得评价结果具有高度代表性和科学性.NPKM的SFI值最大且与其他处理均呈显著差异.NPKM、2NPK、NPK各处理SFI值分别高出对照(CK) 31.3%、13.0%和10.1%.SFI值的时间演变为NPKM处理先增后降,临界年限在第12年,N和CK处理缓降,其它处理缓增.一定范围内,二次曲线较直线更能揭示作物产量与SFI的关系,进一步拟合发现,SFI和作物相对产量间符合“S”型波尔兹曼生长曲线,SFI增至0.60时,相对产量增幅趋零,NPKM处理(SFI=0.688)已属于此;模拟可知,作物产量趋稳时相应施肥年限表现为NPKM (2a) <2NPK (8a) <NPK (9a) <NP (11a) <K、NK (13a)<P(14a)处理.综上,长期平衡施肥(NPKM、2NPK和NPK)明显提高土壤综合肥力,NPKM更为显著,但其现状对作物增产已无效,应减施或不施若干年;长期偏施肥对土壤肥力贡献不力,尤其是长期单施氮反使土壤肥力下降.%Based on the data of long-term fertilization experiment in red paddy soil at Jinxian county, Jiangxi province. Integrated soil fertility was evaluated and its effects were analyzed by fuzzy mathematics and statistics methods. The results showed that organic matter, available N, available P, available K, physical clay, aggregate ratio and aggregate stability were proposed a minimum data set( MDS) for soil fertility assessment and the evaluation results produced by MDS had good representativeness and scientificalness. Among all treatments, SFI for NPKM was maximum and had a significant difference with SFI for other treatments. Compared to the control, the SFI of NPKM, 2NPK and NPK treatments was about 31. 3% , 13. 0% and

  5. Analysing long term discursive processes

    DEFF Research Database (Denmark)

    Horsbøl, Anders

    What do timescales - the notion that processes take place or can be viewed within a shorter or longer temporal range (Lemke 2005) - mean for the analysis of discourse? What are the methodological consequences of analyzing discourse at different timescales? It may be argued that discourse analysis...... in general has favored either the analysis of short term processes such as interviews, discussions, and lessons, or the analysis of non-processual entities such as (multimodal) texts, arguments, discursive repertoires, and discourses (in a Foucaultian sense). In contrast, analysis of long term processes...... which extend beyond the single interaction, for instance negotiations or planning processes, seems to have played a less important role, with studies such as Iedema 2001 and Wodak 2000 as exceptions. These long term processes, however, are central to the constitution and workings of organizations...

  6. 长期施肥对砂姜黑土作物产量及土壤物理性质的影响%Effects of Long-Term Fertilization on Crop Yield and Soil Physical Properties in Lime Concretion Black Soil

    Institute of Scientific and Technical Information of China (English)

    王道中; 花可可; 郭志彬

    2015-01-01

    [Objective] Maintaining and improving soil fertility, in order to improve soil productivity, is an important part of the sustainable development of agriculture. The effects of long-term combined applications of chemical fertilizer with cow manure (CM), pig manure (PM), and wheat straw (WS) on crop yields and physical properties were investigated in a lime concretion black soil to explore the mechanism of soil fertility improvement.[Method]The crop yield and soil physical properties in seven treatments composed of chemical fertilizer and combined applications of chemical fertilizer with CM, PM, WS from a long-term experimental field established in 1982 were studied to evaluate the effects of different fertilization treatments on crop yield and soil physical properties of lime concretion black soil in the Mengcheng county of Anhui province.[Result]The wheat and soybean yield of the treatment without fertilization in the long-term continuously decreased, and the average annually decreasing rates were 39.0 kg·hm-2 and 70.9 kg·hm-2, respectively. The yield of wheat and soybean fluctuated at a very low level after 25 years. The wheat yield of the treatments with a single chemical fertilizer or a combined application of chemical fertilizer and organic material showed an increasing trend. The yield of the treatments with a combined application of chemical fertilizer and organic material increased when compared to the treatment that applied a single chemical fertilizer; the average annual yield increase rate was above 5%. The yield-increasing effect of cow manure was better than pig manure, and of pig manure was better than straw. The interannual fluctuation range of wheat and soybean yield was large, the coefficient of variation (CV) of the treatment without fertilization was the highest, while applied fertilizer could decreaseCV.The CV of the treatment with a combined application of chemical fertilizer and organic material was lower than the single chemical fertilizer

  7. 长期不同施肥对南方黄泥田水稻子粒品质性状与土壤肥力因子的影响%Effects of long-term fertilization on rice grain qualities and soil fertility factors in yellow paddy fields of southern China

    Institute of Scientific and Technical Information of China (English)

    王飞; 林诚; 李清华; 何春梅; 李昱; 林新坚

    2011-01-01

    Based on data collected at the 26th year of a long-term fertilization experiment in the yellow paddy in Fujian, we investigated the influences of different long-term fertilization regimes on the characters of rice grain quality and the factors of soil fertility.The results show that compared with the control (No fertilization, CK), total essential amino acid contents of rice grain in the treatments of chemical fertilizer plus cattle manure ( NPKM), chemical fertilizer plus straw (NPKS) and chemical fertilizer (NPK) are significantly increased by 25.6%, 16.1% and 13.1% respectively.Contents of coarse protein and starch are also 1.11 -1.41 and 2.3 -3.9 percentage points higher, respectively, with the most significant effect found in the NPKM treatment.Likewise, the N and P contents of rice grain are significantly higher in the NPKM, NPKS, NPK treatments compared with the CK, particularly with an increase of 26.1% and 31.1% in the NPKM treatment.Moreover, the Ca, Mg and S contents of rice grain in the NPKM treatment are increased as well compared with the CK treatment.The amino acid content of rice grain is significantly and positively correlated to the N, P, Mg and S contents of rice grain, and the starch content of rice grain is significantly and positively correlated to the N, Ca and S contents.Soil organic matter and nutrient availability(particularly K) are increased in the NPKM, NPKS and NPK treatments compared with the CK.Furthermore, the key fertility factors including soil organic matter, available N and available P are significantly and positively correlated with amino acid and starch contents of rice grain, and soil available N and available P are significantly and positively correlated with N content and P content of rice grain, respectively.In conclusion, the NPKM treatment is the best fertilization regime for yellow paddy fields, considering overall effects of fertilization on rice yield, grain quality and soil fertility.%在福建黄泥田

  8. Long-Term Follow-Up after Treatment of Cryptorchidism

    DEFF Research Database (Denmark)

    Thorup, Jorgen; Cortes, Dina

    2016-01-01

    When considering long-term prognosis and results in adult age following treatment of cryptorchidism in childhood there are three main issues to be discussed: cosmetics, fertility, and malignancy. In the present review, the most recent research on the topics related to summaries of well-known know...

  9. Effects of Long-Term Fertilization on Organic Carbon and Nitrogen Accumulation and Activity in a Paddy Soil in Double Cropping Rice Area in Dongting Lake of China%长期施肥对洞庭湖双季稻区水稻土有机碳、氮积累及其活性的影响

    Institute of Scientific and Technical Information of China (English)

    李文军; 彭保发; 杨奇勇

    2015-01-01

    Objective]Soil organic matter and its activity are essential indexes for assessing soil fertility, so the responses of total organic carbon (TOC) and nitrogen (TN) accumulation and its activity to various long-term fertilization in a double cropping rice soil were studied in Dongting Lake region, China, which can provide a scientific basis for improving fertilization management and soil fertility in paddy soils.[Method]Based on a national experimental platform which was arranged in the Hanshou county, Hunan province, test samples in the surface (0-20 cm) and subsurface (20-40 cm) of a paddy soil after 26 years of fertilization treatments were collected and SOC, TN content and storage were measured, as well as soil microbial biomass carbon (MBC) and nitrogen (MBN), dissolved organic carbon (DOC) and nitrogen (DON) contents were also analyzed. The experiment included six treatments: (1) CK, unfertilized control; (2) CF, farmers’ practice of applying chemical fertilizer NPK; (3) NK, application of chemical fertilizer NK; (4) NPK, balanced application of chemical fertilizer NPK; (5) LOM, combined application of chemical fertilizer NPK and 30% organic fertilizer; (6) HOM, combined application of chemical fertilizer NPK and 60% organic fertilizer.[Result]The content of TOC at 0-20 cm soil layer changed slightly when no fertilizer applied for 26 years and its value only increased by 0.64 g·kg-1 throughout the period, suggesting that long-term cropping rice was beneficial to TOC sequestration. After long-term application of chemical or organic fertilizer, the content of TOC and TN in two soil layers increased significantly (P0.05) among the CF, NK and NPK treatments. With the deepening of soil, the proportion of labile organic N fractions to TN and microbial quotient decreased, but the proportion of DOC to TOC increased. No matter which soil layer was concerned, the MBC/TOC, DOC/TOC, MBN/TN and DON/TN ratios in soil increased when fertilization was adopted, and the

  10. Long term stability of power systems

    Energy Technology Data Exchange (ETDEWEB)

    Kundur, P.; Gao, B. [Powertech Labs. Inc., Surrey, BC (Canada)

    1994-12-31

    Power system long term stability is still a developing subject. In this paper we provide our perspectives and experiences related to long term stability. The paper begins with the description of the nature of the long term stability problem, followed by the discussion of issues related to the modeling and solution techniques of tools for long term stability analysis. Cases studies are presented to illustrate the voltage stability aspect and plant dynamics aspect of long term stability. (author) 20 refs., 11 figs.

  11. Impact of ROS and sperm DNA damage on the outcome of in vitro fertilization under long-term fertilization*%长时受精过程中活性氧及精子的DNA损伤对体外受精结局的影响

    Institute of Scientific and Technical Information of China (English)

    张娜; 张耀恒; 张轶; 赵世彬; 乜照燕; 李亚丽

    2013-01-01

    Objective To detect the change of sperm DNA damage and reactive oxygen species at different time after insemination and explore the adverse effects of long-term fertilization on outcome of in vitro fertilization by comparative analysis of the laboratory and clinical data of short-term fertilization and long-term fertilization. Methods One hundred and forty-six patients who underwent in vitro fertilization and embryo transfer for female infertility were enrolled in the study. Semen was collected on the oocyte retrieval day and treated with Pure Sperm. Three samples were taken after the sperm concentration adjusted to 10×106/ml and the volume of each sample was 1.0ml. The first sample was defined as 0h after insemination (when oocytes added sperm), the second sample was defined as 5h after insemination(5h after oocytes added sperm) and the third sample was defined as 20h after insemination(20h after oocytes added sperm). Each sample was used for detecting of H2O2, CTA and sperm DNA damage. Sperm DNA damage levels were determined with acridine orange staining. The concentrations of hydrogen peroxide and catalase were detected by colorimetric. On the embryo transfer day, the patients were divided into two groups: one group of patients chose short-term fertilized embryo to transfer, one group of patients chose long fertilized embryo to transfer. Results The levels of sperm DNA damage and hydrogen peroxide in the sperm wash medium at 20h after insemination were higher than those at 0h and 5h after insemination significantly (P0.05). Conclusion For long-term fertilization, the sperm could produce excessive reactive oxygen and enhanced sperm DNA damage,which led to have an adverse effect on the oocytes and embryos. Short-term fertilization could reduce the polyspermy rate and improve the high quality embryo rate under no effecton the fertilization rate and cleavage rate.%  目的通过检测精液处理后不同时间的精子DNA损伤程度与活性氧的变化,

  12. The Differences in Root Traits and Photosynthesis of Wheat in Lime Concretion Black Soil under Long-term Different Fertilization Patterns%长期不同施肥模式下砂姜黑土小麦根系和光合的差异性研究

    Institute of Scientific and Technical Information of China (English)

    张向前; 曹承富; 张存岭; 乔玉强; 杜世州; 李玮; 赵竹; 陈欢

    2016-01-01

    In order to clarify the difference in the effects of long-term single fertilization model,we studied the effects of five kinds of long-term (34 years)located fertilization models on root traits,photosynthesis and yield of wheat in lime concretion black soil.The results showed that the root traits of CK(no fertilizer application)was the worst,the total root length,total root surface area,total root volume and total root tips of MNPK(mixed application of organic and chemical fertilizer with the same amount of nitrogen)and HMNPK(mixed application of organic and chemical fertilizer with the larger amount of nitrogen)were significant higher than that of NPK(application of single chemical fertilizer)and M(application of single organic fertilizer),in addition,the differences between NPK and M in total root surface area,average root diameter and total root volume were insignificant.When compared to long-term application of single chemical fertilizer(NPK)and organic fertilizer(M),the treatment of long-term mixed ap-plication of organic and chemical fertilizer(MNPK and HMNPK)could help to enhance the top-three leaves width and length of wheat.At booting stage,the photosynthetic rate,stomatal conductance and transpiration rate of MNPK were the highest,but there was no significant difference with HMNPK;at middle of filling stage(MNPK and HMNPK happen lodging),the photosynthetic characteristics of NPK and M were better than that of MNPK and HMNPK,and the photosynthetic characteristics of MNPK was also better than that of HMNPK(the most serious lodging).At boo-ting stage,compared to long-term application of single chemical fertilizer and organic fertilizer,the treatment of mixed application of organic and chemical fertilizer could help to improve wheat chlorophyll fluorescence parame-ters;At middle of filling stage,the chlorophyll fluorescence parameters of M was perform the best,and the ΦpsⅡ , Fv /Fm,ETR,qP of MNPK were significant higher than that of HMNPK.Total root length

  13. Asthma Medicines: Long-Term Control

    Science.gov (United States)

    ... Size Email Print Share Asthma Medicines: Long-term Control Page Content Article Body Corticosteroids Synthetic versions of ... form, they are used exclusively for long-term control; they are not very effective for acute symptoms. ...

  14. Long term complications after radical cystoprostatectomy with ...

    African Journals Online (AJOL)

    Long term complications after radical cystoprostatectomy with orthotopic diversion in male ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... Objective: To evaluate the long-term outcomes beyond 1 year, both ...

  15. 长期施肥对黑土有机无机复合度及结合态腐殖质的影响%Effect of long-term fertilization on the organo-mineral complexation and the combined forms of humus of black soil

    Institute of Scientific and Technical Information of China (English)

    迟凤琴; 蔡姗姗; 匡恩俊; 张久明; 周宝库

    2014-01-01

    Effect on long-term different fertilization on the combined forms of humus and the organo-mineral complexation of black soil were studied on the basis of long-term located experiment. The results showed that the contents of organic carbon in soil and heavy fraction and the quantity of organo-mineral complexation were increase with varying degrees under different treatments of long-term fertilization, the degree of organo-mineral complex was decrease in the same way. The contents of the loosely combined humus was richest, the contents of the stsbly combined humus was moderate, the contents of the tightly combined humus was the smallest in all fertilizer treatments. The content of the loosely combined humus, the stsbly combined humus and the ratio of loosely to tightly combined humus tended to increase and the content of loosely combined humus and ratio of loosely to stably combined humus tended to decrease under the fertilizer treatments. The fertility of soil under the chemical fertilizer treatment tended to increase in 0-20 cm layer and tended to decrease in 20-40 cm layer. The organic manure and chemical fertilizers treament improved of soil in the greatest extent, made the humus most active, the influence is stability in the two layers. The effects of the organo-mineral complexation under fertilization in 0-20 cm layer was greater than 20-40 cm layer and the effects of combined forms of humus under fertilization in 20-40 cm layer was greater than 0-20 cm layer.%以黑土长期定位试验为基础,研究长期不同施肥对黑土腐殖质结合形态及有机无机复合度影响。结果表明,长期不同施肥均可不同程度提高土壤的有机碳、重组有机碳、原土复合量,降低原土复合度。三种施肥处理的土壤结合态腐殖质以松结态为主,紧结态其次,稳结态最少。施肥提升土壤的松结态及稳结态腐殖质含量、土壤松/紧比值;降低紧结态腐殖质含量及土壤松/稳比值。

  16. Advances in Influences of Long-term Fertilization on Organic Carbon,Nitrogen Component and Microbial Diversity in Soil%长期施肥对土壤有机碳、氮组分及微生物多样性影响的研究进展

    Institute of Scientific and Technical Information of China (English)

    李清华

    2013-01-01

    Organic carbon and organic nitrogen in soil are closely related to soil environment and soil fertility.Through combining domestic and foreign literatures about long-term fertilization experiment, the law of differences in soil organic carbon and nitrogen component under different fertilization models were researched, and the response characteristics of microbial diversity to different fertilization models were also discussed.Moreover, the future studying direction for this field was prospected.%土壤有机碳、氮组分与土壤环境、土壤肥力密切相关.通过综合国内外长期定位施肥试验研究报道,研究不同施肥方式下土壤有机碳、氮组分的差异规律,探讨微生物多样性的响应特征,并对该领域今后研究方向提出展望.

  17. Study on Wheat Yield Stability in Huaibei Lime Concretion Black Soil Area Based on Long-Term Fertilization Experiment%长期施肥下淮北砂姜黑土区小麦产量稳定性研究

    Institute of Scientific and Technical Information of China (English)

    陈欢; 曹承富; 孔令聪; 张存岭; 李玮; 乔玉强; 杜世州; 赵竹

    2014-01-01

    Objective The research was conducted to explore the responsive mechanism of wheat yield stability to long-term fertilization. [Method] Based on long-term fertilization experiment in Yangliu village of Anhui province, the trend of change in wheat average yield, annual fluctuation of wheat yield and soil nutrients content in 5 fertilization patterns were investigated:non-fertilization (CK), application of single chemical fertilizer (NPK), application of single organic fertilizer (M), mixed application of organic and chemical fertilizer with the same amount of nitrogen (MNPK), mixed application of organic and chemical fertilizer with the larger amount of nitrogen (HMNPK).[Result]It was discovered that wheat yield in CK showed a declining trend by 5.81 kg·hm-2·a-1, while fluctuated increasing emerged in fertilization treatments. Wheat yield trend line of HMNPK was in the first place, but MPK had been chasing after by 9.75 kg·hm-2·a-1. Wheat yield trend line of NPK was higher than M in the earlier stage of experiment, whereas it was caught up by M after 22 years. In respect of wheat average yield of 32 years, HMNPK and MNPK were higher than other fertilization treatments, with 5 544.3 kg·hm-2 and 5 200.6 kg·hm-2, respectively; NPK took the third place, by increasing 614.6% of that in the non-fertilization treatment; wheat yield increasing of M was the lowest, however, no obvious difference was found between M and NPK. The contribution of soil capacity in lime concretion black soil had been decreasing in early 10 years then stopped and kept stable at 10%;the contribution ratio of fertilizer had been increasing in early 10 years, and then maintained dynamic balance at the level of 80%-90%. It enhanced the coefficient of variation (CV) and reduced sustainable yield index (SYI) without fertilization, which made yield stability the worst;the wheat yield stability of HMNPK and MNPK was better than NPK which was better than M. Compared with CK, fertilizer application

  18. Gratitude in Long Term Care

    Directory of Open Access Journals (Sweden)

    Brooke Abrams Sunding

    2015-04-01

    Full Text Available An exploratory study was conducted to examine the effectiveness of a group gratitude intervention with 29 permanent residents at a long term care/skilled nursing facility in improving elder mood, behavior and well- being over a 3 week time period. The sample included individuals diagnosed with dementia, other cognitive impairment, major depressive disorder, insomnia and generalized anxiety disorder. The gratitude intervention consisted of asking elders to share what they are thankful for at the dinner table each day. Measures included the Elder Well Being Scale and The Dinner Rating Scale. On both measures, higher scores indicated better functioning. To test the hypothesis that post treatment elder well-being will be significantly higher than pretreatment elder well-being ratings, a one-way ANOVA was conducted. Post-hoc tests revealed a statistically significant increase in Elder Well Being Scale scores. An ANOVA of comparing Dinner Ratings demonstrated a nonsignificant increase over the 3 week experiment. Implications are discussed.

  19. 有机肥和化肥长期施用对土壤活性有机氮组分及酶活性的影响%Long-term effects of mineral versus organic fertilizers on soil labile nitrogen fractions and soil enzyme activities in agricultural soil

    Institute of Scientific and Technical Information of China (English)

    宋震震; 李絮花; 李娟; 林治安; 赵秉强

    2014-01-01

    本文以中国农业科学院山东禹城长期定位施肥试验为平台,研究了长期施用有机肥和化肥26年后对土壤活性氮库不同组分[颗粒有机氮(POM-N)、可溶性有机氮(DON)、微生物量氮(SMBN)及轻组有机氮(LFOM-N)]及土壤酶活性的影响。结果表明,与不施肥相比,长期施肥显著提高了土壤全氮、颗粒有机氮、可溶性有机氮、微生物量氮以及轻组有机氮的含量,长期施有机肥效果好于化肥,施用高量有机肥效果好于施用常量有机肥。常量施用量下,50%有机肥和50%化肥配施处理其土壤全氮和活性有机氮库各组分含量与高量化肥处理的相当。长期施化肥处理土壤全氮及活性有机氮库各组分含量随施肥量的增加而显著增高。 POM-N对土壤全氮的贡献率最高,且明显受施肥方式的影响,LFOM-N对土壤全氮的贡献率不随施肥方式的改变而变化。长期施肥处理土壤脲酶、碱性磷酸酶和蔗糖酶活性显著增加,它们之间及与土壤全氮、速效磷及有机碳含量间呈现显著或极显著相关性,脲酶活性与土壤各活性氮组分间也存在显著或极显著相关性;但长期施肥后土壤过氧化氢酶的活性低于不施肥处理。%In this paper, the effects of long-term application of organic fertilizer and chemical fertilizer on soil labile nitrogen fractions and some kinds of soil enzyme activities ( urease, catalase, alkaline phosphatase and sucrase ) were studied based on a 26-year long-term field experiment in Chinese Academy of Agricultural Sciences Research Station in Yucheng City, Shandong province, China.The results show that, compared with CK, long term fertilization significantly increases soil total nitrogen , particle organic nitrogen ( POM-N ) , dissolved organic nitrogen ( DON ) , microbial biomass nitrogen ( MBN ) and light fraction organic nitrogen ( LFON ) contents . Treatments of applying organic

  20. Effects of Different Long-term Fertilization Models on Culturable Microbial Quantity and Enzyme Activities of Lime Concretion Black Soil%长期不同施肥模式对砂姜黑土可培养微生物数量和酶活性的影响

    Institute of Scientific and Technical Information of China (English)

    张向前; 陈欢; 乔玉强; 曹承富; 杜世州; 李玮; 赵竹

    2016-01-01

    Based on long-term located fertilization experiment (year 1981—) in lime concretion black soil area, we studied the effects of without fertilizer application CK, long-term application of single chemical fertilizer NPK, long-term application of single organic fertilizer M, long-term mixed application of organic and chemical fertilizer MNPK (with the same amount of nitrogen) and HMNPK (with the larger amount of nitrogen) on culturable microbial quantity and enzyme activities in soil, in order to reveal the response mechanism of soil microbial quantity and enzyme activities to different fertilization models, and to provide scientific basis and theoretical help for improving lime concretion black soil fertility and quality. The quantity of bacteria, fungi, actinomycetes and Azotobacter of CK was lower than that of other fertilization treatments, and the quantity of bacteria, actinomycetes and Azotobacter of M was significantly higher than that of NPK at middle of filling stage, while the difference in the quantity of fungi between M and NPK was insignificant. The quantity of bacteria, fungi and actinomycetes of MNPK and HMNPK was higher than that of NPK and M, compared to NPK and M, MNPK increased the quantity of bacteria, fungi and actinomycetes by 47.0%, 21.1%, 32.1% and 23.2%, 11.7%, 20.2%, respectively. The difference in the quantity of bacteria, fungi and actinomycetes between MNPK and HMNPK was insignificant at middle of filling stage, while the quantity of Azotobacter of MNPK was higher than that of HMNPK. The activities of invertase, dehydrogenase, acidic and neutral phosphatase and protease of M were higher than that of NPK at middle of filling stage, and increased by 20.9%, 22.1%, 17.7%, 18.4%, 10.0%, respectively. When compared to long-term application of single chemical fertilizer and organic fertilizer, the treatment of long-term mixed application of organic and chemical fertilizer obviously increased the activities of soil invertase, dehydrogenase

  1. Long-term duration of function of ovarian tissue transplants

    DEFF Research Database (Denmark)

    Andersen, Claus Yding; Silber, Sherman J; Berghold, Stinne Holm

    2012-01-01

    These three case reports describe the long-term duration of function of ovarian cortical tissue grafts among patients in a university fertility preservation programme in Europe and in a private practice programme in the USA. One woman underwent sterilizing cancer treatment and had frozen ovarian...... or to alleviate its symptoms. These three case reports describe the long-term duration of function of ovarian cortical tissue grafts among patients in a university fertility preservation programme in Europe and in a private practice programme in the USA. One woman underwent sterilizing cancer treatment and had...... tissue transplanted, and two women underwent fresh ovarian tissue transplants. The function of ovarian cortical strips has continued for more than 7years in these three women, with the birth of eight healthy babies following a single graft per patient. In addition to these three cases, transplantation...

  2. EFFECTS OF LONG-TERM FERTILIZATION ON COMPOSITION AND FRACTAL FEATURE OF SOIL MICRO-AGGREGATES UNDER A WHEAT-MAIZE CROPPING SYSTEM%长期施肥对小麦-玉米轮作土壤微团聚体组成和分形特征的影响

    Institute of Scientific and Technical Information of China (English)

    龚伟; 颜晓元; 蔡祖聪; 王景燕

    2011-01-01

    The composition and fractal dimension (D) of micro-aggregates in 0 ~ 20 cm soil layer were studied on a long-term fertilized field under wheat-maize cropping rotation in North China Plain, and relationships of soil fertility with compositional proportion of characteristic soil micro-aggregates (PCM , < 20 μm/(250 ~ 20) μm) , ratio of the content of < 20 μm particle-size to the content of 2 000 ~ 20 μm particle-size content in soil micro-aggregates determination (RMD, <20 μm/(2 000 ~20)μm) and D were evaluated. The long-term fertilization experiment was designed to include 7 treatments: fertilizer NPK (NPK) , organic manure (OM), half organic manure with chemical fertilizer NPK (1/20MN), chemical fertilizer NP (NP), chemical fertilizer PK (PK) , chemical fertilizer NK (NK) and control (CK). After 18 years of fertilization, all the treatments, except CK showed lower values of PCM, RMD and D, and higher nutrients content and enzyme activity. Among the fertilization treatments, Treatment OM was the lowest in PCM,RMD and D, followed by Treatment 1/20MN, and the treatments with chemical fertilizers. Balanced application of fertilizers (Treatment NPK) was lower in PCM,RMD and D than imbalanced use of fertilizers (Treatments NP, PK, and NK). PCM, RMD and D were closely related to crop yield, soil organic matter, hydrolysis N, and enzyme activity. The findings indicate that the use of organic manure alone or in combination with fertilizer NPK and balanced application of fertilizer NPK are key to improving soil micro-aggregate composition, decreasing PCM, RMD and D, and increasing soil nutrient preserving and supplying capacity; and that PCM, RMD and D can be used as integrated quantitative indexes to evaluate the soil fertility under a long-term fertilization cropping system.%通过对华北平原小麦-玉米轮作农田生态系统18 a田间施肥试验,研究了长期不同施肥处理对耕层(0 ~20 cm)土壤微团聚体组成及分形维数(D)的影

  3. Effects of Long-term Different Fertilization Regimes on the Rhizospheric Microbial Community Functional Diversity in Paddy Field%长期施肥对双季稻田根际土壤微生物群落功能多样性的影响

    Institute of Scientific and Technical Information of China (English)

    唐海明; 肖小平; 李微艳; 孙耿; 程凯凯

    2016-01-01

    reflected the main carbon source utilized by rhizosphere microbial community. Our objective was to explore the rhizosphere microbial community functional diversity of a paddy field at early and late rice mature stages under different long-term fertilization regimes in a double cropping rice system. A long-term experiment was established in 1986 in Ningxiang county of Hunan Province, China, and five different fertilizer treatments were applied: (1) no fertilizer input (CK), (2) mineral fertilizer alone (MF), (3) rice residue plus mineral fertilizer (RF), (4) 30% organic matter and 70% mineral fertilizer (OM1), and (5) 60% organic matter and 40% mineral fertilizer (OM2). We analyzed the rhizosphere microbial community functional diversity of the fields with the above five treatments using BIOLOG system. The results showed that both applications of organic manure mixed with chemical fertilizer, and chemical fertilizer alone caused high increase of the AWCD while straw incorporation had less effect on the AWCD, which effect was even lower than in the treatment without fertilizer. It was implied that long-term fertilization regime resulted in the variation of the carbon utilization efficiency of rhizosphere soil microbial communities. In addition, the indices of McIntosh under different fertilization regimes were ordered as follows: OM2>OM1>MF>CK>RF at mature stages of early and late rice. And the indices of Richness, Shannon under different fertilization regimes were ordered as follows: OM2>OM1>RF>CK>MF at mature stages of early and late rice. PCA analysis indicated that there were different carbon-substrate-utilization patterns among different fertilizer treatments. Carbohydrates and Amino acids were the main carbon resources utilized by rhizosphere microbes. There were significant differences in carbon-substrate-utilization patterns among different fertilizer treatments. Therefore, the combined application of chemical fertilizer and recycled organic manure could significantly

  4. Long-term dynamics of the hemiparasite Rhinanthus angustifolius and its relationship with vegetation structure

    NARCIS (Netherlands)

    Ameloot, Els; Verheyen, Kris; Bakker, Jan P.; De Vries, Yzaak; Hermy, Martin

    2006-01-01

    Questions: 1. How are the long-term dynamics of the root hemiparasite Rhinanthus angustifolius related to vegetation structure, grassland management and climate? 2. Does R. angustifolius have a long-term impact on standing crop and community composition? Location: A formerly fertilized grassland,

  5. 长期施用氮肥对土壤细菌硝化基因多样性及组成的影响%Effect of Long-Term Application of Nitrogen Fertilizer on the Diversity of Nitrifying Genes (amoA and hao) in Paddy Soil

    Institute of Scientific and Technical Information of China (English)

    陈春兰; 吴敏娜; 魏文学

    2011-01-01

    以中国科学院桃源农业生态试验站水稻长期定位试验为平台(28°55′49.8″N,111°26′25.7″E),运用PCR、克隆文库构建等分子生物学技术研究长期单施氮肥(尿素)对亚硝化基因(amoA和hao)多样性及其群落结构的影响.结果表明,长期单施氮肥使amoA基因多样性降低(Shannon指数减少了11%),而hao基因多样性几乎不受影响,对amoA优势基因型的影响大于对hao基因的影响;长期施用氮肥使amoA和hao基因的菌群组成分别发生了显著性(p=0.02)和极显著性变化(p=0.002).系统发育分析表明amoA基因主要与未经培养的氨氧化细菌基因相似,相似率主要集中在86%~99%,可能主要来自亚硝化螺菌属;而hao基因主要与Silicibacteria、亚硝化螺菌属(Nitrosospira)和甲基球菌属(Methylococcus)相似,相似率在66%~80%,长期施用氮肥使hao基因主要集中在α-Proteobacteria纲且与Silicibacteria有较近的亲缘关系.总体来说,长期单施氮肥使水稻土中亚硝化基因amoA的多样性降低,使amoA与hao的群落组成发生显著变化.%The aim of this study was to determine the effect of long-term ( 16 years) application of nitrogen fertilizer on the diversity of nitrifying genes (amoA and hao) in paddy soil on the basis of long-term paddy field experimental station (started in 1990) located in Taoyuan, with the molecular approaches of PCR, constructing libraries and sequencing. The fertilizer was urea and no fertilizer was as control. The Shannon index showed that long-term application of nitrogen fertilizer made the diversity of amoA gene descend while no effect on the diversity of hao gene. The LIBSHUFF statistical analyses demonstrated that both amoA and hao libraries of CK and N treatments were significantly different from each other and the rarefaction curves of libraries failed to meet the plateaus indicating that there were lots kinds of genes haven't been detected. The results of blasting with GenBank and

  6. 用分形理论评价长期施肥对土壤理化性质的影响%Effects of Long-term Fertilization on Soil Properties Using Fractal Theory

    Institute of Scientific and Technical Information of China (English)

    刘小粉; 刘春增; 李本银; 王守刚

    2012-01-01

    This study investigated the effects of different fertilization practices on soil physical properties and fractal features of aggregates, and evaluated the effects of fractal features on soil physical properties especially on aggregate stability using an existing fractal model. The results showed that the fractal dimension (D) seemed smaller under treatments applying organic materials than under treatment applying chemical fertilizer alone. The fractal dimension had significantly negative correlation with mean weight diameter (MWD) and geometric mean diameter (GMD) , so it could reflect aggregate size distribution as well as soil structure stability. Besides, higher D often indicated higher clay content,higher soil bulk density,and lower organic matter content,while lower D indicated more macroaggregates,lower soil bulk density,and higher organic matter content. The former often induced less macro-pores and more micro-pores, which were bad for soil water and nutrition availability,and vice versa. It was concluded that integrated application of organic and chemical fertilizers was essential for maintaining high soil quality. Under conditions where there were limited organic fertilizers,it was necessary to return crop residues into the field.%为探讨不同施肥处理对土壤理化性质和团聚体分形特征的影响以及用分形特征评价长期施肥对土壤理化性质尤其是土壤团聚体稳定性的影响,采用1个现存的分形模型作为主要研究手段.结果表明,有机肥—化肥混施分形维数较小,单施化肥则较大.分形维数与团聚体平均质量直径(MWD)、几何平均直径(GMD)呈显著负相关,因此,分形维数能同时反映团聚体粒径分布和土壤结构稳定性.另外,分形维数越高,黏粒含量越高,土壤容重越大,有机质含量越少;反之,分形维数越低,大团聚体和有机质含量越高,土壤容重越小.分形维数高时,易导致大孔隙分布少,微小孔隙分布多,

  7. Effects of long-term fertilization on microorganisms in flue-cured tobacco grown soil%长期施肥对植烟土壤微生物的影响

    Institute of Scientific and Technical Information of China (English)

    丁伟; 叶江平; 蒋卫; 霍沁建; 陈晓明; 梁永江; 张长华; 袁玲

    2012-01-01

    利用7年的定位施肥试验,研究了不施肥(CK)、 单施化肥(CF)和有机无机肥配施(MCF)对植烟土壤微生物的影响。平板计数、 微生物碳、 氮含量和磷脂脂肪酸的测定结果均表明,土壤微生物数量以有机无机配施的处理最多,单施化肥次之,不施肥最少。在3种施肥处理的土壤中,分别检测出20(CK)、 27(CF)和31种(MCF)磷脂脂肪酸; 施肥提高了代表细菌(1220碳)和放线菌(10Me17: 0和10Me18: 0)的磷脂脂肪酸; 但是,代表真菌的磷脂脂肪酸18: 1ω9c无显著变化(CF)或显著降低(MCF)。有机无机肥配施处理显著提高了土壤微生物的多样性指数和优势度指数,说明有机无机配施改善了土壤生态环境,微生物种群丰富,优势种群突出。在土壤自生固氮菌、 磷细菌和钾细菌中,分离率最高的是芽孢杆菌属,在26%50%之间变化。有机无机肥配施还提高了这3种有益微生物的数量,单施化肥则无显著影响。此外,在有机无机肥配施的土壤中,自生固氮菌、 磷细菌和钾细菌的多样性指数、 均匀度指数和优势度指数均较高。从土壤微生物的角度看,生产上采用有机无机肥配施很有必要。%A 7-year experiment was carried out to investigate the effects of no fertilizer (CK), chemical fertilizer (CF) and the mixture of manure and chemical fertilizer (MCF) on microorganisms in flue-cured tobacco grown soils. Plate count, microbial C and microbial N as well as phosphor lipid fatty acids (PLFAs) showed highest microorganisms in the soil treated with MCF, less with CF and lowest with CK. There were 20 (CK), 27 (CF) and 31 types of PLFAs (MCF) in soils, respectively. Fertilization increased the PLFAs contained in bacteria (12–20C) and actinomycetes (10Me 17:0和10Me18:0). There were no obvious changes in fungal PLFAs (18:1ω9c) in

  8. 长期定位施肥对稻麦轮作农田土壤杂草种子库的影响%Changes in Weed Seed Bank Community of Agricultural Soils in Rice-Wheat Rotation Field Due to Long-Term Fertilization

    Institute of Scientific and Technical Information of China (English)

    蒋敏; 沈明星; 施林林; 沈新平; 戴其根

    2013-01-01

    [Objective] Characterizing the long-term effect of fertilization on weed seed bank community will aid in developing sustainable weed management practices and promoting crop yield.[Method] Weed seed bank was measured within a long-term fertilization from 1980 in the Taihu Lake region.Inorganic fertilizer treatments were selected as follows:CK (no fertilizer),N (N fertilizer),NP (N plus P fertilizer),NK (N plus P fertilizer),PK (P plus K fertilizer) and NPK (N plus P and K fertilizers).Weed seed density and community surveys were conducted and bio-diversity indices including Simpson index,Shannon index,Richness index,Evenness index were also calculated,at the same time,redundancy analysis (RDA) and correlation analysis were executed to mining the relationship between fertilizer management and weed seed bank.[Result] Seed densities of Monochoriav aginalis,Lindernia procumbens,Ammannia baccifera,Polygonum lapathifolium,Eleocharis yokoscensis,and Cyperus were high and dominant in different treatments,these weeds did a lot of damage to the growth of crops.Most of the weed seed densities decreased when nitrogen fertilizer was applied,the density ofE.yokoscensis decreased when phosphorus fertilizer was applied while the density of M.aginalis increased.The number of species and richness index of NPK treatment were the highest (P< 0.05),but its evenness index,Shannon index and Simpson index were significantly lower than those of the other treatments.[Conclusion] Long-term fertilization had changed the weed seed bank community in local area.The seed density decreased significantly when nitrogen fertilizer was applied.Phosphorus and potassium fertilizer had effects on the number of different weed species in the field.%[目的]解析长期不同施肥措施下稻麦两熟制农田土壤杂草种子库的异构性及其养分影响因素,为稻麦高产与杂草控制协同的养分管理提供依据.[方法]以太湖地区31年的长期肥料定位试验土壤为材料,采

  9. Effects of long-term fertilization on spring season weed community in winter fallow paddy field in red soil area under double-rice cropping system%长期施肥对红壤双季稻冬闲田春季杂草群落的影响

    Institute of Scientific and Technical Information of China (English)

    董春华; 曾希柏; 石林; 高菊生

    2015-01-01

    利用始于1982年的红壤双季稻田长期施肥定位试验,于2012年采用田间调查法研究了在无机肥(化肥 NPK)与有机肥(M)氮磷钾养分等量条件下,长期施用有机肥、无机化肥和有机肥无机肥配施模式下红壤双季稻冬闲田春季杂草生物量及群落密度和群落多样性的变化。结果表明:有机肥无机肥配施改变了优势杂草种类,增加了杂草总密度和总生物量。化肥氮钾配施有机肥(NKM)处理的杂草种类数量最多,化肥氮磷配施有机肥(NPM)处理的最少。施肥处理中, M处理的杂草群落多样性指数、均匀度指数和优势度指数均最高,分别为1.1186、0.7323和0.6297;其杂草总密度最低,为297.0株×0.25m-2。NPK处理的杂草总生物量最低,为58.0 g×0.25m-2。NPM处理的杂草群落多样性指数值、均匀度及优势度指数值均显著低于其他处理;其杂草总密度和杂草总生物量均最高,分别为539.7株×0.25m-2和109.5 g×0.25m-2;其优势杂草日本看麦娘的密度为428.0株×0.25m-2,相对密度为79.31%,明显高于其他处理优势杂草的密度和相对密度。春季杂草总干物质量与土壤碱解氮正相关(相关系数为0.703),与土壤 pH 负相关(相关系数为0.697),相关性不显著;与土壤有效磷显著正相关(相关系数为0.758*)。长期不同施肥模式下红壤稻田磷素是导致田间春季杂草群落特征变化的主要因素,通过改变土壤有效磷和碱解氮含量及土壤pH,能有效调控红壤双季稻冬闲田春季杂草生物量及群落密度和生物多样性。%An investigation in winter fallow field of double-rice cropping system in the red soil area was carried out in 2012 in a long-term fertilization experiment (started in 1982) site in Hengyang Red Soil Experiment Station of Chinese Academy of Agricultural Sciences to study the species, biomass and biodiversity of weed communities during spring season. The investigated long-term

  10. Effects of long-term fertilization on weed community characteristics and carbon, nitrogen and phosphorus stoichiometry during winter-spring season in yellow-clay paddy fields of South China%长期施肥对南方黄泥田冬春季杂草群落及其C、N、P化学计量的影响

    Institute of Scientific and Technical Information of China (English)

    林新坚; 王飞; 王长方; 林诚; 李清华; 何春梅; 李昱

    2012-01-01

    As an important agronomic measure, fertilization affects not only crop growth, but also field weeds and community composition. However, the effects of different fertilization on weed community characteristics are still not fully understood. To that end, a long-term experiment was set up in 1983 at Fujian Experimental Observatory Station, a station for the monitoring (via experimental plots) of long-term farmland conservation practices. The station belongs to the Ministry of Agriculture and is located at 119°04'10" E and 26°13'31" N. The soils at the station are the typical yellow-clay paddy soils originating from foot-slope deposited low-hilly red soils of mid-low-yield paddy fields. The influences of different long-term fertilization schemes on the characteristics of field weed communities and carbon (C), nitrogen (N) and phosphorus (P) stoichiometry during winter-spring seasons were investigated. The main aim was to lay the scientific basis for southern paddy soil fertility improvement and weed management and utilization. The results showed that compared with the control (no fertilization, CK), Shannon uniform index (E) was 0.03—0.07 lower in the treatments of chemical fertilizer plus cattle manure (NPKM), chemical fertilizer plus straw (NPKS) and chemical fertilizer (NPK). Margalef abundant index (DMG) also dropped in NPKM and NPKS treatments. Shannon diversity index (H'), a comprehensive indicator, was 0.02-0.16 lower in fertilization treatments. Compared with CK, weed biomass increased by 89.6%~214.7% in all fertilization treatments. Weed N, P and K contents increased as well, and was most significant for NPKM treatment. In terms of accumulated nutrients, the treatments rank of paddy soils was NPKM > NPKS > NPK. Furthermore, weed C/N and C/P ratios dropped in all fer-tilization treatments. Some significant correlations were noted among weed C/N, C/P and N/P ratios and C/N, C/P, N/P ratios of soil and biomass. Different fertilization schemes influenced weed

  11. HOME LONG-TERM CARE IN POLAND

    Directory of Open Access Journals (Sweden)

    Ewa Kułagowska

    2011-06-01

    Full Text Available The considerable proportion of the elderly, the chronically ill and the disabled in community is an economic and organizational challenge for the state social policy. It requires a large, steadily increasing financing from the public funds and creating an optional care model to fulfill the needs of citizens and guarantee high quality services. Development of the long-term care is one of the problems to be solved. This paper presents: – a long-term care forms, organization and tasks; – a role of long-term care but particularly home longterm care to protect health in Poland; – problems related with home long-term care functioning.

  12. Long-term dynamics simulation: Modeling requirements

    Energy Technology Data Exchange (ETDEWEB)

    Morched, A.S.; Kar, P.K.; Rogers, G.J.; Morison, G.K. (Ontario Hydro, Toronto, ON (Canada))

    1989-12-01

    This report details the required performance and modelling capabilities of a computer program intended for the study of the long term dynamics of power systems. Following a general introduction which outlines the need for long term dynamic studies, the modelling requirements for the conduct of such studies is discussed in detail. Particular emphasis is placed on models for system elements not normally modelled in power system stability programs, which will have a significant impact in the long term time frame of minutes to hours following the initiating disturbance. The report concludes with a discussion of the special computational and programming requirements for a long term stability program. 43 refs., 36 figs.

  13. 黄绵土长期定位试验中硝态氮剖面分布特征%Effect of Long-term Located Fertilization on NO3--N Accumulation in the Profile of Loessial Soil

    Institute of Scientific and Technical Information of China (English)

    杨孔雀; 郝明德; 臧逸飞; 孙占育; 高亚利

    2011-01-01

    对1982年建立的长期肥料定位试验的土壤剖面硝态氮含量变化进行分析.结果表明,经25 a种植冬小麦施用不同肥料后,土壤0~400 cm土层硝态氮含量差异显著,施N、NP、NPK在200cm出现累积峰,各处理在300 cm以下硝态氮含量显著减少(低于1.0 mg/kg).对于CK、和单施P处理的100 cm以下土壤因长期没有N肥的补给,作物的长期吸收利用,而趋于耗竭(低于1.0 mg/kg);单施N和NP配施处理0~400cm土壤剖面中的氮残留量高达1 323.3kg/hm2,是不施肥的23.3倍,NPK配施也达655.9kg/hm2,是不施肥的11.1倍;M处理的残留量维持在1 018.6~1 753.1 kg/hm2左右,与化肥处理相比残留量显著增加,M处理比CK处理、NM处理比N处理、NPM处理比NP处理和NPKM处理比NPK处理分别增加了93.1%、21.1%、32.5%和83.3%.单施N的硝态氮年残留率最大,相当于施肥量的48.6%;NP配施残留率33.6%,NPK为21.3%.M、NM、NPM和NPKM处理的硝态氮残留率分别为2.6%、33.2%、25.2%和22.8%.平衡施肥能显著减少硝态氮含量,相同施氮水平下,配施磷肥、钾肥、有机肥的硝态氮残留率显著减少.%A 25 years fertilization experiment was carried out with wheat-grown Loessial soil in North China, and the profile of nitric nitrogen content in soil was analyzed. The results showed that there is significant differences on NO3--N contents in the 0-400 cm soil layer, after 25 years cultivation of the winter wheat. It showed an peak accumulation at 200 cm soil layer, and reduced significantly under 300 cm soil layer, ( less than 1.0 mg/kg) in N, NP and NPK treatment. When organic fertilizer supplied only, the accumulation of NO3--N increased in the surface of soil and tended to exhaust under the 120 cm soil layer. The NO3--N content in N and NP treatment was more than 1323.3kg/hm2 ,about 23.3 times of that in CK treatment, and 655.9 kg/hm2 and about 11.1 times in NPK treatment.The NO3 -N in manure treatment was about 1 028.6 to 1 753

  14. Long-term survival after perforated diverticulitis

    NARCIS (Netherlands)

    J. Vermeulen (Jan); M.P. Gosselink (Martijn Pieter); W.C.J. Hop (Wim); E. van der Harst (Erwin); B.E. Hansen (Bettina); G.H.H. Mannaerts (Guido); P-P. Coene (Peter Paul); W.F. Weidema (Wibo); J.F. Lange (Johan)

    2011-01-01

    textabstractAim: Short-term survival after emergency surgery for perforated diverticulitis is poor. Less is known about long-term survival. The aims of this study were to evaluate long-term survival after discharge from hospital and to identify factors associated with prognosis. Method: All patients

  15. Virtual Models of Long-Term Care

    Science.gov (United States)

    Phenice, Lillian A.; Griffore, Robert J.

    2012-01-01

    Nursing homes, assisted living facilities and home-care organizations, use web sites to describe their services to potential consumers. This virtual ethnographic study developed models representing how potential consumers may understand this information using data from web sites of 69 long-term-care providers. The content of long-term-care web…

  16. Telicity marking in Hungarian

    Directory of Open Access Journals (Sweden)

    Éva Kardos

    2016-10-01

    Full Text Available This paper explores the encoding of telicity in Hungarian. While proposing a mereological, scalar semantic analysis, it shows that Hungarian uses a telicity-marking strategy in which it contrasts with English, where telicity is not the direct consequence of an overt marker but arises as a cumulative effect of specific, well-definable properties of various components of verbal predicates including the head verb and its argument(s. A major contribution of the analysis, which mainly addresses telicity marking in the class of non-creation/non-consumption predicates in neutral sentences, lies in the fact that it reveals important cross-linguistic differences with respect to the aspectual role of verbal particles and resultative/locative expressions and the referential properties of telic verbal predicates. As for the former, it is demonstrated that Hungarian verbal particles and resultative/locative expressions mark telicity by directly placing bounds on events by virtue of serving an event maximalizing function, whereas the English counterparts of these elements do not have such direct event-bounding effects. As for the latter, it emerges that in Hungarian quantized reference is a necessary and sufficient condition for telicity in cases where in English it is only sufficient.

  17. Comprehensive Analysis of a Long-term Fertilizer Trial from 1989 to 1996 in Typical Red Soil in Guangxi%广西红壤木薯肥料多年定位试验(1989~1996)综合分析①

    Institute of Scientific and Technical Information of China (English)

    郑华; 李军; 田益农; 盘欢; 俞奔驰; 文峰

    2016-01-01

    A long-term fertilizer trial on cassava from 1989-1996, including 2 cassava varieties (SC201 and SC205) and 15 fertilization treatments (chemical fertilizers and farmyard manure), to provide scientific basis for cassava fertilizing. Results showed that cassava yields and weight of shoot were both significantly different among years and cassava cultivars, respectively. The cassava yield of SC201 and SC205 increased significantly in 3/8 and 5/8 years, respectively, with the application of farmyard manure (FYM). Cassava yields were significantly improved, in most of the observed years (SC201 6/8, SC205 7/8), after NPK fertilizers were applied with the proportionate quantity according to the "suggested NPK fertilization", which is 100∶50∶100 kg/hm2 N∶P2O5∶K2O. The correlation of cassava yields and the NPK fertilizing amount could be fit with parabolic equation in 3/8 years and 6/8 years for SC201 and SC205, respectively. The shoot weight increased following a parabolic curve with the increase of NPK fertilization, while the starch content decreased. N fertilizer increased cassava yields in most of the years (5/8 and 8/8 years for SC201 and SC205, respectively). And quantity of N fertilizers and cassava yields could be fit with parabolic equation in 5/8 and 3/8 years for SC201 and SC205, respectively. The shoot weight was increased with N fertilizer applied. P fertilizers increased the yield of SC201 and SC205 in 3/8 and 5/8 years, respectively. The K fertilization increased the cassava yield of both varieties in 2/8 years, respectively, but significantly increased shoot weight in 3/4 years for each variety, respectively. Cassava yield and shoot weight was increased by N fertilization, N is the first limiting factor to cassava yield in the typical red soil;K fertilization can also increase shoot weight. Application of P fertilizer could increase the yield of SC205 in more years than K fertilizer. The shoot weight, yield, starch yield of SC201 was higher than

  18. Effects of Different Long-term Fertilizer Managements on Microbial Biomass Carbon, Microbial Biomass Nitrogen and Microbial Quotient in Paddy Soil during Barley Growth Periods%长期施肥对大麦生育期双季稻田土壤微生物生物量碳、氮和微生物商的影响

    Institute of Scientific and Technical Information of China (English)

    唐海明; 郭立君; 肖小平; 汤文光; 孙继民; 汪柯; 李微艳

    2015-01-01

    Fertilizer inputs is the most important agricultural management practice affecting soil carbon and nitrogen content. Moreover, soil carbon and nitrogen provide a direct source for soil organisms. In China, only few studies have been conducted on the influence of long-term fertilizer and organic matter with fertilizer application on the soil microbiological properties. Our objective was to explore the characteristics of soil microbial biomass carbon (w(SMBC)), soil microbial biomass nitrogen (w(SMBN)) and soil microbial quotient in paddy soil during barley (Hordaum vulgare L.) growth periods with different long−term fertilizer managements in the double cropping rice system, we analyzed thew(SMBC),w(SMBN), soil microbial quotient and grain yield of barley by using mineral fertilizer alone (MF), rice residues plus mineral fertilizer (RF), 30% organic matter and 70% mineral fertilizer (OM1), 60% organic matter and 40% mineral fertilizer (OM2), and without fertilizer (CK). The long-term experiment was set up in 1986 in Ningxiang county, Hunan province, China. The results showed that different fertilization managements on paddy soil over the 28 years significantly affected soil chemical and microbial properties. That is, thew(SMBC),w(SMBN) and soil microbial quotient in paddy soil were increased by long-term fertilizer managements during barley growth periods. Meanwhile, thew(SMBC),w(SMBN) and soil microbial quotient reached the maximum at heading stage of barley. The activities ofw(SMBC) were increased by 20.04%, 26.47%, 45.94% and 51.42% with MF, RF, OM1 and OM2 at heading stage of barley, and the activities ofw(SMBN) were increased by 12.87%, 18.42%, 32.16 % and 36.55% with MF, RF, OM1 and OM2 at heading stage of barley compared with the CK, respectively. Furthermore, thew(SMBC),w(SMBN) and soil microbial quotient with OM1 and OM2 was significantly higher than that of MF, RF, CK at the main growth stages of barley. And thew(SMBC),w(SMBN) and soil microbial quotient

  19. 长期施用氮磷钾肥和石灰对红壤性水稻土酸性特征的影响%Effect of Long-term Fertilization and Lime Application on Soil Acidity of Reddish Paddy Soil

    Institute of Scientific and Technical Information of China (English)

    鲁艳红; 廖育林; 聂军; 周兴; 谢坚; 杨曾平; 吴浩杰

    2016-01-01

    利用34年的长期定位施肥试验,研究不施肥(CK)、施氮磷钾肥(NPK)和氮磷钾化肥配施石灰(NPK+CaO)对红壤性水稻土不同形态酸、土壤盐基离子及水稻植株阳离子吸收量的影响,探讨土壤交换性H+和Al3+占交换性酸的比例、土壤盐基离子、植株带出阳离子数量与土壤酸度的关系.结果表明,长期NPK处理早、晚稻土壤pH 较CK处理分别降低0.2和0.3个单位,交换性酸提高2.3倍和4.2倍,水解性酸提高35.4%和40.0%;NPK+CaO处理早、晚稻土壤pH较NPK处理分别提高0.5和0.7个单位,较CK处理分别提高0.3和0.4个单位,交换性酸、水解性酸均显著低于NPK和CK处理(p CK> NPK. Exchangeable Al3+ was dominant to exchangeable acidity in acidic soil,and the ratio of exchangeable Al3+ to exchangeable acidity increased with increasing soil acidification. The effects of fertilization,regardless of fertilization mode,on soil CEC,exchangeable Ca2+,Mg2+,exchangeable base ions and base saturation were all very significant. Soil exchangeable base ions were dominated with exchangeable Ca2+,accounting for 81.8%~89.3%. Long-term liming significantly increased the content of soil exchangeable Ca2+. Treatment NPK+CaO was 40.1% and 62.9% higher in soil exchangeable Ca2+ than Treatments CK and NPK,respectively. Exchangeable Ca2+,exchangeable base ions and base saturation were positively related to soil pH,but negatively to exchangeable acidity and hydrolytic acid,and exchangeable Mg2+ was negatively to exchangeable acidity and hydrolytic acid,while exchangeable Na+ was negatively to hydrolytic acidity only. Treatments NPK+CaO and NPK did not vary much,but were both significantly higher than CK(p NPK> CK,in terms of potassium and magnesium uptake and total cation uptake by the crop,the followed an order of NPK> NPK+CaO> CK,and in terms of sodium uptake they followed an order of CK> NPK> NPK+CaO. The removal of Ca,Mg,K and Na and the cations in total with the crops harvested did

  20. Effects of long-term fertilization on soil water and nutrient with Triticum aestivum L.succession in dryland of Loess Plateau%黄土旱塬长期施肥对小麦连作土壤养分和水分的影响

    Institute of Scientific and Technical Information of China (English)

    危锋; 郝明德

    2011-01-01

    To provide reference for reasonable use of water and fertilizer resources in dry-land of Loess Plateau,the study on the change of soil nutrient and water was conducted under the condition of 22-year Triticum aestivum L. succession based on the long-term fertilizer experiment. The six treatments were no fertilizer (CK) , nitrogen fertilizer (N) , phosphate fertilizer (P) , manure fertilizer (M) , nitrogen and phosphate fertilizers ( NP) , nitrogen and phosphate fertilizers with manure ( NPM ). Nutrient in tilth soils (0 -20 cm) , and water contents and water storage in soil profiles (0 -300 cm) were measured. The results showed that for the contents of soil organic matter, total N, total P, available N, available P, and available K in tilth soils, they increased by 55.44% , 45.24% , 29.63% , 67. 16% , 186.96% and 123.65% , respectively, after long-time M application. For contents of soil organ matter, total N, total P, available N, available P, and available K in tilth soils, they increased by 65.67% , 50.00% , 40. 74% , 72. 37% , 324. 58% and 191. 17% , respectively, after long-time NPM application. The water contents in tilth soils were 18. 19% , 17. 99% , 17. 66% , 17. 42% , 16. 96% and 16. 29% after longtime NPM, M, P, CK, N and NP treatments, respectively. The distribution characteristics of water contents in soil profile were similar for long-time NPM, M and NP treatments. The water storage of 0 - 300 cm soil layers were 666. 73, 656. 23, 629. 41, 536. 88, 504. 26 and 488. 47 mm in the P, CK, N, NP, M and NPM treatments, respectively. Compared to the CK, the wate storage in the P treatment increased by 1.60% , but decreased by 4.09% in the N treatment, 18. 19% in the NP treatment, 23. 16% in the M treatment and 25. 56% in the NPM treatment. The long-term application of single manure and chemical fertilizer combined with manure could increase nutrient and water contents in tilth soils. The water storage in 0 - 300 cm soil layers significantly decreased by the

  1. 长期培肥对烤烟-小麦轮作红壤各级团聚体氮及其酶活性的影响%Influence of the Long-term Fertilization on Nitrogen and Enzymatic Activities in Aggregates of Tobacco-Wheat Grown Red Soil

    Institute of Scientific and Technical Information of China (English)

    罗世琼; 杨宇虹; 晋艳; 袁玲; 黄建国

    2012-01-01

    以云南省烟草农业科学研究院研和试验基地13年长期定位试验为平台,以化肥配施有机肥(CFM)、单施化肥(FM)和不施肥(CK,对照)3种处理土壤为研究材料,利用干筛法分离土壤团聚体,研究长期培肥对烤烟-小麦轮作红壤团聚体、有机质、氮含量、酶活性的影响及其相关性。结果表明:长期化肥配施有机肥有利于大团聚体的形成,2~1mm团聚体土壤的分配率显著高于单施化肥和对照;使耕层土壤有机质、各形态氮(全氮、碱解氮、硝态氮和铵态氮)及酶活性大幅度改善,并且,除硝态氮以外,各级团聚体土壤有机质及各形态氮含量变化趋势为CFM〉CF〉CK;化肥配施有机肥各级团聚体土壤蛋白酶、脲酶、蔗糖酶、脱氢酶活性明显高于单施化肥和对照,其中脲酶、蔗糖酶活性与土壤有机质和4种形态氮呈显著正相关,蛋白酶和脱氢酶与上述营养呈负相关,但不显著。化肥配施有机肥有利于增加土壤大团聚体的分配率,提高土壤有机质、全氮及碱解氮等的含量及酶活性,对烤烟、小麦生长意义重大。%Soil samples, which were treated with combined application of fertilizers and organic manure (CFM), application of fertilizer manure(FM) and no fertilization(CK), respectively, were collected from Yanhe test site of Yunnan Academy of Tobacco Agricultural Science for 13 years located experiment. Distri- bution of soil aggregates, organic matter and nitrogen concentrations, and enzyme activities of tobacco-wheat grown red soils for long-term fertilization were investigated by dry sieving method for soil aggregates. The aim was to evaluate whether long-term fertilization influenced tobacco-wheat grown red soils, and their relationships. Distribution rate of soil macroaggregates(2~ 1 ram) for long-term CFM compared with CF and CK could be significantly increased. Content of organic matter, multi-form N

  2. 长期不同施肥方式对砷在典型壤质潮土及作物中累积的影响%Effects of long-term fertilization on As (arsenate) accumulation in typical fluvo-aquic soils and crops

    Institute of Scientific and Technical Information of China (English)

    王擎运; 张佳宝; 信秀丽; 赵炳梓; 邓西海; 钦绳武

    2012-01-01

    Huang-Huai-Hai Plain is a strategic grain production base in China with a wild distribution of fertile fluvo-aquic soils. During the past 20 years, high-input intensive agriculture with excess chemical fertilizer application has sustained high grain yields. However, unreasonable field management has resulted in potential pollution issues in the plain. In this study, the effects of long-term differential fertilization practices on the accumulation of arsenate (As) in typical fluvo-aquic soils and crops were investigated. Field experiments were launched in 1989, in which 7 treatments were established. The treatments included OM (organic manure), OM+NPK (50% organic manure + 50% chemical fertilizer), NPK, NP, PK, NK and CK (the control experiment with no fertilizer). With over 20 years (1989-2009) of cultivation, As in the surface (0~20 cm) and subsurface (20~40 cm) soil layers markedly accumulated. The soil As content was, however, too low for loading negative effects on eco-agricultural safety. As accumulation in the plain was mainly affected by irrigation and deposition, and relatively less affected by different fertilizer applications. The content of As in phosphorus (P) fertilizers was higher than in nitrogen (N) and potassium (K) fertilizers or in organic manure (OM). Hence P fertilization was the main drive of soil As accumulation in the plain. Nevertheless, long-term P fertilization did not significantly increase soil As content since it was largely used up by crops. Also As accumulation trend slowed with OM fertilization. Crop tissue content of As was in the order of root > stalk > grain. Grain As content was not only significantly lower than that of root or stalk, but also than that of China's national standard. For different fertilization treatments, wheat tissue As content was in the order of PK > OM > OM+NPK > NPK > NP > NK > CK. This was somehow similar to that of soil available P, which was indirectly affected by soil organic matter content. Under OM

  3. Long-Term Ownership by Industrial Foundations

    DEFF Research Database (Denmark)

    Børsting, Christa Winther; Kuhn, Johan Moritz; Poulsen, Thomas

    2016-01-01

    Short-termism has become a serious concern for businesses and policy makers and this has inspired a search for governance arrangement to promote long term decision making. In this paper we study a particularly long-term ownership structure, which is fairly common in Northern Europe, particularly...... in Denmark. Industrial foundations are independent legal entities without owners or members typically with the dual objective of preserving the company and using excess profits for charity. We use a unique Danish data set to examine the governance of foundation-owned companies. We show that they are long-term...... in several respects. Foundations hold on to their shares for longer. Foundation-owned companies replace managers less frequently. They have more conservative capital structures with less leverage. Their companies survive longer. Their business decisions appear to be more long term. This paper supports...

  4. Long Term Care Minimum Data Set (MDS)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Long-Term Care Minimum Data Set (MDS) is a standardized, primary screening and assessment tool of health status that forms the foundation of the comprehensive...

  5. Long Term Care Minimum Data Set (MDS)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Long-Term Care Minimum Data Set (MDS) is a standardized, primary screening and assessment tool of health status that forms the foundation of the comprehensive...

  6. Long-Term Care Ombudsman Program

    Science.gov (United States)

    ... Strategic Plan Federal Initiatives Career Opportunities Contact Us Administration on Aging (AoA) Long-Term Care Ombudsman Program ( ... Prevention HIV/AIDS Nutrition Services Oral Health Elder Justice & Adult Protective Services Elder Justice Coordinating Council Prevention ...

  7. Pituitary diseases : long-term clinical consequences

    NARCIS (Netherlands)

    Klaauw, Agatha Apolonia van der

    2008-01-01

    This thesis describes various studies during the long-term follow-up of patients after treatment for pituitary diseases. The focus of this thesis is acromegaly, growth hormone deficiency, sleep and quality of life. Various aspects are described.

  8. Long-term outcome of meniscectomy

    DEFF Research Database (Denmark)

    Roos, Ewa M.; Ostenberg, A; Roos, H;

    2001-01-01

    To describe the long-term influence of meniscectomy on pain, functional limitations, and muscular performance. To assess the effects of radiographic osteoarthritis (OA), gender and age on these outcomes in patients with meniscectomy....

  9. Pituitary diseases : long-term clinical consequences

    NARCIS (Netherlands)

    Klaauw, Agatha Apolonia van der

    2008-01-01

    This thesis describes various studies during the long-term follow-up of patients after treatment for pituitary diseases. The focus of this thesis is acromegaly, growth hormone deficiency, sleep and quality of life. Various aspects are described.

  10. 长期施肥对农田杂草的影响及其适应性进化研究进展%Research advances in weed community and its adaptive evolution in croplands as affected by long-term fertilization

    Institute of Scientific and Technical Information of China (English)

    万开元; 潘俊峰; 陶勇; 汤雷雷; 程传鹏; 陈防

    2012-01-01

    Weeds can compete with crops for resources, resulting in the yield reduction of crops, while play an indispensable role in maintaining the ecological balance of cropland and its sustainable utilization. The application of chemical fertilizers not only greatly accelerated the evolution of soil fertility, but also directly affected the weed growth, its community succession, and genetic evolution in croplands. Therefore, how to scientifically constitute a nutrient management strategy in cropland has become a realistic issue in modern agriculture. This paper comprehensively reviewed the related literatures, and summarized the effects of long-term fertilization regimes on the weed species, community structure, and genetic evolution. Through thoroughly analyzing the weaknesses of the current weed management, it was suggested that the weed control in croplands should be balanced with weed biodiversity, and the research on the long-term fertilization regimes affecting weed genetic diversity and its molecular ecological adaptability should be strengthened, which would have significance in assessing the genetic diversity of weeds under selective fertilization pressure, the potential of weed survival and evolution, and the molecular mechanisms of weed adaptive evolution, so as to supply a broader sense for the comprehensive management of weeds in croplands.%杂草一方面与作物竞争资源而造成作物减产,另一方面在维持农田生态平衡以及保持农田可持续利用方面起着不可或缺的作用.化学肥料的施用显著加快了农田土壤肥力演变的进程,也直接影响了农田杂草的生长、群落演替及遗传进化.因此,如何科学合理地制定农田养分管理对策是现代农业发展的现实问题.本文就长期施肥对农田杂草物种、群落结构的影响以及杂草的遗传与适应性进化三个方面的研究结果进行了收集整理;综合分析了杂草营养管理的薄弱环节,指出在治理杂草的

  11. The Release Kinetics of Non-Exchangeable Potassium in Red Soil and Its Organo-Mineral Complex of Long-Term Fertilizer Experiments%长期施肥红壤及其有机无机复合体非交换性钾释放动力学

    Institute of Scientific and Technical Information of China (English)

    岳龙凯; 王伯仁; 黄庆海; 柳开楼; 蔡泽江; 李冬初; 黄晶; 张会民

    2015-01-01

    [Objective]The objective of this study is to research the non-exchangeable potassium release characteristics in red soil and its complex of different long-term fertilizers, to explore the differences of potassium supply capacity of soil caused by long-term different fertilization, and to clarify non-exchangeable potassium (K) release ability in bulk soils and different size fractions of organo-mineral complex.[Method]The experiment was based on two fertilization experiments of over 20 years, one of which was located at Jinxian, Jiangxi Province and the other at Qiyang, Hunan Province. Organo-mineral complexes were separated from bulk soil with the fraction sizes of100 µm by the ultrasonic beating and siphon method. The non-exchangeable K release from bulk soil and its organo-mineral complex samples were extracted using oxalic acid. Before extracting, the bulk soil and its organo-mineral complex samples were calcium saturated, and the data of the accumulation of non-exchangeable K release from bulk soil and its organo-mineral complex were used to simulate a kinetics equation to study the law of non-exchangeable K release.[Result]After 300 hours of extraction, the accumulation of non-exchangeable K release showed that at the Jinxian site, the amount of non-exchangeable K released by soil with mixed utilizing chemical nitrogen, phosphorus and potassium fertilizer combined with manure (NPKM) and mixed utilizing chemical nitrogen, phosphorus, and potassium fertilizer (NPK) increased by 98.0 and 81.0 mg·kg-1 compared with mixed utilizing chemical nitrogen and phosphorus (NP), respectively, with the increase ratio was 30.7% and 25.4%, respectively. However, at the Qiyang site, the amount of non-exchangeable K release by NPKM and NPK increased by 130.0 and 40.0 mg·kg-1 compared with NP, respectively, and the increase ratio was 52.1% and 16.0%, respectively. The application of K fertilizer increased the accumulation of non-exchangeable K release significantly, especially

  12. Long-term outcomes after severe shock.

    Science.gov (United States)

    Pratt, Cristina M; Hirshberg, Eliotte L; Jones, Jason P; Kuttler, Kathryn G; Lanspa, Michael J; Wilson, Emily L; Hopkins, Ramona O; Brown, Samuel M

    2015-02-01

    Severe shock is a life-threatening condition with very high short-term mortality. Whether the long-term outcomes among survivors of severe shock are similar to long-term outcomes of other critical illness survivors is unknown. We therefore sought to assess long-term survival and functional outcomes among 90-day survivors of severe shock and determine whether clinical predictors were associated with outcomes. Seventy-six patients who were alive 90 days after severe shock (received ≥1 μg/kg per minute of norepinephrine equivalent) were eligible for the study. We measured 3-year survival and long-term functional outcomes using the Medical Outcomes Study 36-Item Short-Form Health Survey, the EuroQOL 5-D-3L, the Hospital Anxiety and Depression Scale, the Impact of Event Scale-Revised, and an employment instrument. We also assessed the relationship between in-hospital predictors and long-term outcomes. The mean long-term survival was 5.1 years; 82% (62 of 76) of patients survived, of whom 49 were eligible for follow-up. Patients who died were older than patients who survived. Thirty-six patients completed a telephone interview a mean of 5 years after hospital admission. The patients' Physical Functioning scores were below U.S. population norms (P shock had a high 3-year survival rate. Patients' long-term physical and psychological outcomes were similar to those reported for cohorts of less severely ill intensive care unit survivors. Anxiety and depression were relatively common, but only a few patients had symptoms of posttraumatic stress disorder. This study supports the observation that acute illness severity does not determine long-term outcomes. Even extremely critically ill patients have similar outcomes to general intensive care unit survivor populations.

  13. Anticipating Long-Term Stock Market Volatility

    OpenAIRE

    Conrad, Christian; Loch, Karin

    2012-01-01

    We investigate the relationship between long-term U.S. stock market risks and the macroeconomic environment using a two component GARCH-MIDAS model. Our results provide strong evidence in favor of counter-cyclical behavior of long-term stock market volatility. Among the various macro variables in our dataset the term spread, housing starts, corporate profits and the unemployment rate have the highest predictive ability for stock market volatility . While the term spread and housing starts are...

  14. 长期施肥对褐土及其微团聚体磷素形态分布和有效性的影响%Effects of Long-term Fertilization on Fractions and Distribution and Availability of Phosphorus in Cinnamon Soil and Its Micro-aggregates

    Institute of Scientific and Technical Information of China (English)

    韩志卿; 韩志才; 张电学; 王秋兵; 吴素霞; 常连生; 谢新宇; 杨会民

    2011-01-01

    通过8年定位试验,研究了长期施肥对褐土及其微团聚体中磷素形态分布和有效性的影响.结果表明,褐土磷素组成以无机磷为主,各级微团聚体各形态磷素含量均随粒级减小而增加,磷素有效性< 10 μm粒级最高,10~50 μm粒级最低.不施肥处理土壤及其微团聚体各形态磷素含量显著减少;施肥均可提高土壤及其微团聚体磷素含量,全磷和无机磷含量以增量NPK化肥处理增加最多,有机磷和有效磷含量则以有机肥(物)料配施化肥处理较高,微团聚体各粒级磷素消耗或积累幅度因施肥制度而异.单施化肥处理土壤及其微团聚体中磷有效性降低,有机肥(物)料配施常量NPK化肥处理积累态磷有效性显著提高.采用有机肥(物)料配施常量NPK化肥是改善土壤磷素肥力的有效措施.%Eight years location experiment was conducted in cinnamon soil in Hebei province to study the effect of long-term fertilization on fractions and distribution and availability of phosphorus in cinnamon soil and its micro-aggregates. The results showed that the composition of phosphorus in cinnamon soil was main inorganic phosphorus. With the sizes of micro-aggregates decreased, the content of every P fractions increased. The effectiveness of phosphorus in < 10 μm micro-aggregates was highest, and in 10 -50 μm micro-aggregates lowest. No fertilization remarkably decreased the content of every P fractions in cinnamon soil and its micro-aggregates. Fertilization increased the content of phosphorus in cinnamon soil and its micro-aggregates. The increase of the content of total phosphorus and inorganic phosphorus with increment NPK fertilizers was most. The content of organic P and available P with application organic manure combined with usual NPK was higher than the other treatments. Range of P consumption and accumulation in every sizes micro-aggregates was different under different fertilizer regimes. The constant NPK

  15. Long-term phosphorus fertility in wastewater-irrigated cropland.

    Science.gov (United States)

    Jaiswal, D; Elliott, H A

    2011-01-01

    Land treatment of municipal wastewater effluent is a proven method for augmenting freshwater resources and avoiding direct nutrient discharges to surface waters. We assessed changes in soil test phosphorus (P) of the Ap horizon of cropped fields continuously irrigated for 26 yr with secondary effluent from the Penn State University wastewater treatment plant. For annual P additions averaging 97 kg P ha(-1), Mehlich-3 P (M3P) response in the 0- to 20-cm surface soil (initially MINTEQ suggests complexation of Al by dissolved organic carbon at site pH conditions. Loss of Al from the surface layer lowered its P-sorbing capacity, causing added effluent-P to move into the subsoil. Results suggest that current management practices can continue for many years without exceeding the surface soil M3P environmental threshold (200 mg kg(-1)) used in state P-based nutrient policies.

  16. 同步辐射软X射线近边吸收谱方法研究长期施肥对黑土有机碳官能团的影响%Effects of Long-Term Fertilization on Organic Carbon Functional Groups in Black Soil as Revealed by Synchrotron Radiation Soft X-Ray Near-Edge Absorption Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    王楠; 王帅; 王青贺; 董培博; 李翠兰; 张晋京; 高强; 赵屹东

    2012-01-01

    以定位20年的黑土肥料试验为平台,利用同步辐射软X射线近边吸收谱(C-1s NEXAFS)方法,研究了长期施用化肥以及化肥配施玉米秸秆对土壤有机碳官能团的影响.结果表明:与不施肥的空白处理(CK)相比,单施化肥(N,NPK)后土壤的芳香C和羧基C含量增加,脂族C和羰基C含量下降,脂族C/芳香C比值降低;与单施化肥处理相比,化肥配施玉米秸秆后芳香C含量下降而脂族C含量增加,脂族C/芳香C比值增加,并随玉米秸秆用量增加表现的更为明显;无论配施玉米秸秆与否,NPK肥混施处理的芳香C、脂族C以及脂族C/芳香C比值均高于单施N肥处理.上述结果说明,单施化肥比不施肥使土壤有机碳官能团中芳香类化合物的相对比例增加,而脂肪烃类化合物的相对比例下降;化肥配施玉米秸秆则比单施化肥增加了脂肪烃类化合物的相对比例,配施高量比低量玉米秸秆的增加趋势更为明显,同时NPK肥混施比单施N肥有利于提高脂肪烃类化合物的相对比例.C-1s NEXAFS方法能够原位表征长期定位施肥条件下土壤有机碳官能团组成的变化.%A 20 years (1984-2004) stationary field experiment was conducted to evaluate the effects of long-term application of chemical fertilizers (N or NPK) alone or in combination with low (0.125 kg o hm~z) or high dose of corn stalk (0. 25 kg · hm‐2) on organic carbon functional groups in black soil using synchrotron radiation soft X-ray near-edge absorption spectroscopy (C-ls NEXAFS). Compared with the control (CK) treatment, the aromatic C and the carboxyl C of soil increased, whereas the aliphatic C, the carbonyl C and the aliphatic C/aromatic C ratio decreased after the application of chemical fertilizer alone. After the application of chemical fertilizations in combined with corn stalk, the aromatic C decreased while the aliphatic C and the aliphatic C/aromatic C ratio increased as compared to N or NPK fertilizer

  17. Effects of long-term fertilization on grain and soil in yellow contents of Zn, B, Cu, Fe and Mn in rice paddy fields of southern China%长期不同施肥对南方黄泥田水稻子粒与土壤锌、硼、铜、铁、锰含量的影响

    Institute of Scientific and Technical Information of China (English)

    王飞; 林诚; 李清华; 何春梅; 李昱; 邱珊莲; 林新坚

    2012-01-01

    在福建黄泥田长期定位施肥试验的第26年,研究了不同施肥模式对水稻子粒与土壤微量元素含量的影响。结果表明,与不施肥(CK)相比,化肥+牛粪(NPKM)、化肥+秸秆还田(NPKS)及单施化肥(NPK)处理的水稻子粒Zn、B、Cu含量均有不同程度的提高,并尤以NPKM处理最为明显,三种微量元素含量分别提高14.3%、25.1%、465.2%,均达差异显著水平。NPKM与NPKS处理还不同程度地提高了子粒Mn含量,但各施肥处理的子粒Fe含量均显著降低。各施肥处理尤其是NPKM与NPKS均显著提高了子粒微量元素吸收量。NPK处理的土壤有效B、Fe、Zn、Cu含量与CK相比均呈下降趋势,且有效Zn、Mn含量较试验前土壤分别降低了36.4%与24.6%,而NPKM与NPKS处理缓解了下降趋势,且NPKM处理的土壤有效Zn、B、Mn含量分别较CK提高46.6%、52.0%、43.0%,均达差异显著水平。土壤有机质与子粒B、Cu、Zn含量呈显著正相关,子粒必需氨基酸、粗蛋白与子粒Zn含量呈显著正相关。以上结果说明,长期化肥配施牛粪或秸秆还田有利于提高水稻子粒Zn、B、Cu等微量元素含量和产量,改善子粒营养品质,一定程度上又可缓解土壤有效微量元素含量的下降,是适合南方黄泥田的施肥模式。%Based on data collected at the 26th year of a long term fertilization experiment in the yellow paddy in Fujian, we investigated the influences of different long-term fertilization regimes on the contents of micronutrients in rice grain and soil. The results show that compared with the control (without fertilization, CK), the contents of Zn, B and Cu of rice grains under the treatments of chemical fertilizer plus cattle manure ( NPKM), chemical fertilizer plus straw (NPKS) and chemical fertilizer (NPK) are all increased more or less, especially under the treatment of NPKM which are

  18. CREDIT LEVEL INFLUENCING FACTORS AT HUNGARIAN FARMS

    Directory of Open Access Journals (Sweden)

    Toth Jozsef

    2012-12-01

    Full Text Available In this paper we estimate the impact of different factors on creditability of agricultural farms. According to the literature the collateral (tangible assets, the farm size, productivity, and subsidies should have significant effects on farm loans. We use data from the Hungarian Farm Accountancy Data Network to test our two hypotheses and theoretical assumptions for the period 2001-2010. Because of using panel data, we do our estimations using fixed effects econometrics model to test our assumptions. The results indicate that the chosen factors have significant influence on total liabilities and short- and long-term loans as well. With specially interest of subsidies the growing level of supports decrease the need of other financial tools. At output factors (inclusive farm size have significant and positive effect, same as collateral (tangible assets.

  19. 长期定位施肥对黄土旱塬黑垆土土壤酶活性的影响%Effect of Long-term Fertilization on Soil Enzyme Activities in Dryland Black Humus Soil in the Loess Plateau

    Institute of Scientific and Technical Information of China (English)

    王淑英; 樊庭录; 丁宁平; 姜小凤; 张平良; 苏敏

    2011-01-01

    以30年(1979~2008年)肥料长期定位试验为基础,探讨长期定位施肥对黄土旱塬黑垆土土壤酶活性的影响及不同土壤酶间相关性.结果表明:SNP和MNP处理可提高土酶蔗糖酶活性,比不施肥对照分别增加19.98%、19.14%;土壤脲酶活性单施M效果最佳,较对照提高30.72%,MNP和SNP处理优于其它处理;MNP提高碱性磷酸酶活性的效果最好、增幅196.5%,单施M和SNP效果次之;单施N可提高土壤蛋白酶活性,较对照增加28.3%,而施P有抑制黄土旱塬黑垆土蛋白酶活性的作用.脲酶与碱性磷酸酶呈显著正相关,相关系数为0.7241,过氧化氢酶与碱性磷酸酶、脲酶呈显著负相关.综合考虑,长期有机-无机NP肥配施是促进黄土旱塬黑垆土土壤良性循环、提高耕地质量的有效施肥管理措施.%Effects of long-term fertilization on soil enzyme activities in dryland black humus soil in the Loess Plateau was studied based on the long-term fertilization experiment from 1979 to 2008. The results showed that nitrogen and phosphorus with farmer manure (MNP), nitrogen and phosphorus with straw (SNP) could improve the soil invertase activity compared with no fertilizer (control) increased by 19.98%, 19.14%. Farmer manure (M) had a great effect on soil urease activities increased by 30.72% compared to the control, next to MNP and SNP. MNP could increase alkaline phos- phatase activities by 196.5% compared with the control, next to M and SNP. Only application of N could increase soil protease activities by 28.3% compared with control, while P could inhibit soil protease activities in dryland black humus soil in the Loess Plateau. There was a significant positive correlation between soil urease and alkaline phosphatase with correlation coefficient of 0.7241, while there was significantly negative correlation between catalase and alkaline phosphatase, urease. Organic-fertilizer (M and S) with NP was an effective practice for dryland black

  20. 长期施肥对黄泥田土壤微生物群落结构及团聚体组分特征的影响%Effects of long-term fertilization on soil microbial community structure and aggregate composition in yellow clayey paddy field

    Institute of Scientific and Technical Information of China (English)

    李清华; 王飞; 林诚; 何春梅; 李昱; 钟少杰; 林新坚

    2015-01-01

    -years long term field fertilizer experiment in Fujian Province was used for the investigation . There were four treatments, CK ( without fertilizer ), NPK ( fertilizer N, P and K), NPKM ( NPK plus cattle manure) and NPKS ( NPK plus rice straw ).The soil samples were collected in the 0 -20 cm soil layer, phospholipid fatty acid technique and wet screening method were employed to study the microbial community structure and water-stable aggregate composition , respectively .[Results] Compared with CK , the long-term fertilization could increase the types of soil microbial phospholipid fatty acid by 16.67%-38.89% and soil microbial biomass by 26.71%-47.30%, which had significant differences of bacterial , fungi and actinomycetes .The no fertilization could lead to the shortage of actinomycetes , but the fertilization with cattle manure ( NPKM ) could promote the species and amount of soil microbial .The first and second principal components explained 89.80%of the total variance in soil phospholidid fatty acids which extracted six main variables , C17:1w8 ( Gram-negative bacteria), C12:0 (bacteria), cy19:0w8 (Burkholderia), C17:0 (Arthrobacter), C18:1w7 (Pseudomonas), and C10Me17:0 ( Actinobacteria ) .Meanwhile the NPKM and NPKS treatments could increase the ratios of 0.25-2.0 mm water-stable aggregate by 4.74-8.47 percentage points , and the fertilization could increase the contents of C and N in above aggregate by 1.63%-32.58%and 3.82%-13.74%, respectively .The NPKS treatment could promote the formation of water-stable aggregate larger than 0.25 mm.The NPKM treatment could increase the contents of C and N in aggregate with different sizes .There were significantly positive correlations between bacterial , actinomycetes or total microbial biomass and water-stable aggregate of 0.25-2.0 mm size , while there were significantly negative correlations between bacterial , actinomycetes or total microbial biomass and water-stable aggregate less than 0.25 mm.There were

  1. 不同施肥方式对典型壤质潮土中微量元素积累及其有效性的影响%INFLUENCE OF DIFFERENT LONG-TERM FERTILIZATION PRACTICES ON ACCUMULATION AND AVAILABILITY OF MICRONUTRIENTS IN TYPICAL LOAMY FLUVO-AQUIC SOIL

    Institute of Scientific and Technical Information of China (English)

    王擎运; 张佳宝; 赵炳梓; 邓西海; 信秀丽; 钦绳武

    2012-01-01

    Micronutrient deficiency is commonly demonstrated in farmlands of fluvo-aquic soil, a typical soil type in the Huang-Huai-Hai Plain of China. The objectives of this study were to explore effects of different long-term fertilization practices on balance of micronutrients in the soil, and changes of soil micronutrients in fraction using the BCR sequential extraction method. A field experiment, designed to have 7 treatments, i.e. OM ( Organic Manure) , 1/20M + 1/2 ( Fertilizer) NPK, NPK, NP, PK, NK, and CK ( No Fertilizer) , was laid out and started in 1989. After more than 20 years of fertilization, various extents of accumulation of micronutrients were observed in the surface layer soil (0 ~20cm) , and found to be greatly affected by their transfer between different soil layers. Results of sequential extraction show that the contents of soil available ( DTPA-micronutrient) Fe, Cu and Zn were higher, while the content of soil available Mn was relatively lower than the critical levels in the other alkalic soils. The Residue-Fractions of soil Fe ( > 90% ) , Cu ( >65% ) and Zn ( > 70% ) accounted for a high proportion of their respective total. Interestingly, DTPA, acid soluble and oxidizable fractions of soil micronutrients accumulated more with the increasing soil organic matter level, which was probably the driving factor for the changes of soil micronutrients in fraction. Long term application of K fertilizers also increased DTPA and acid soluble fractions of soil micronutrients, but decreased the total of Fe and Mn in the surface soil layer, while long-term application of P fertilizers decreased the contents of DTPA and acid soluble fractions of soil micronutrients through precipitation, but increased the totals of Cu and Zn.%研究了1989-2009年间长期不同施肥方式对华北地区典型壤质潮土微量元素全量及有效性的影响.田间试验施肥处理包括:有机肥(OM)、1/2OM+ 1/2化肥氮磷钾(NPK)、NPK、NP、PK

  2. Long-term follow-up study and long-term care of childhood cancer survivors

    Directory of Open Access Journals (Sweden)

    Hyeon Jin Park

    2010-04-01

    Full Text Available The number of long-term survivors is increasing in the western countries due to remarkable improvements in the treatment of childhood cancer. The long-term complications of childhood cancer survivors in these countries were brought to light by the childhood cancer survivor studies. In Korea, the 5-year survival rate of childhood cancer patients is approaching 70%; therefore, it is extremely important to undertake similar long-term follow-up studies and comprehensive long-term care for our population. On the basis of the experiences of childhood cancer survivorship care of the western countries and the current Korean status of childhood cancer survivors, long-term follow-up study and long-term care systems need to be established in Korea in the near future. This system might contribute to the improvement of the quality of life of childhood cancer survivors through effective intervention strategies.

  3. Emotional Intelligence of Hungarian Teachers

    Science.gov (United States)

    Baracsi, Ágnes

    2016-01-01

    The research focused on the personal and social competencies of Hungarian teachers as unexplored areas. The participants in the survey were 707 Hungarian teachers from elementary and secondary schools. In view of the expectations of the European Union related to new teacher roles, the following research question was formulated to guide the study:…

  4. Long-term Multiwavelength Observations of Polars

    Science.gov (United States)

    Santana, Joshua; Mason, Paul A.

    2016-06-01

    Polars are cataclysmic variables with the highest magnetic field strengths (10-250 MG). Matter is accreted after being funneled by the strong magnetic field of the white dwarf. We perform a meta-study of multi-wavelength data of polars. Many polars have been observed in surveys, such as SDSS, 2MASS, ROSAT, just to name a few. Some polars have now been detected by the JVLA, part of an expanding class of radio CVs. A large subset of polars have long-term optical light curves from CRTS and AAVSO. We suggest that the long term light curves of polars display a variety of signature behaviors and may be grouped accordingly. Additional characteristics such a binary period, magnetic field strengths, X-ray properties, and distance estimates are examined in context with long-term observations.

  5. Long-term home care scheduling

    DEFF Research Database (Denmark)

    Gamst, Mette; Jensen, Thomas Sejr

    In several countries, home care is provided for certain citizens living at home. The long-term home care scheduling problem is to generate work plans spanning several days such that a high quality of service is maintained and the overall cost is kept as low as possible. A solution to the problem...... provides detailed information on visits and visit times for each employee on each of the covered days. We propose a branch-and-price algorithm for the long-term home care scheduling problem. The pricing problem generates one-day plans for an employee, and the master problem merges the plans with respect...

  6. [Fetal pain: immediate and long term consequences].

    Science.gov (United States)

    Houfflin Debarge, Véronique; Dutriez, Isabelle; Pusniak, Benoit; Delarue, Eléonore; Storme, Laurent

    2010-06-01

    Several situations are potentially painful for fetuses, such as malformations and invasive procedures. Nociceptive pathways are known to be functional at 26 weeks. Even if it is not possible to evaluate the fetal experience of pain, it is essential to examine its immediate and long-term consequences. As early as the beginning of the second trimester, hemodynamic and hormonal responses are observed following fetal nociceptive stimulation, In experimental studies, long-term changes have been noted in the corticotrop axis, subsequent responses to pain, and behavior after perinatal nociceptive stimulation.

  7. Keratoprosthesis: a long-term review.

    Science.gov (United States)

    Barnham, J J; Roper-Hall, M J

    1983-07-01

    A keratoprosthesis (KP), is an artificial cornea which is inserted into an opacified cornea in an attempt to restore useful vision or, less commonly, to make the eye comfortable in painful keratopathy. Results o a retrospective study of 35 patients, with 55 KP insertions, are reviewed with regard to visual acuity, length of time vision is maintained, retention time, and complication. Overall there were a number of long-term real successes, eith retention of the KP and maintenance of improved vision in eyes not amenable to conventional treatment. Careful long-term follow-up was needed, with further surgical procedures often being necessary.

  8. 长期定位施肥对土壤铜、锌形态转化及其空间分布的影响%Effects of Long-term Located Fertilization on the Forms Transformation and Spatial Distribution of Cu and Zn in Soil

    Institute of Scientific and Technical Information of China (English)

    韩晓日; 袁程; 王月; 杨劲峰; 李娜; 张欣昕

    2011-01-01

    The BCR continuous extraction was used to research the soil Cu and Zn contents change and its spatial variability after 31-year fertilization treatments on Shenyang Agricultural University brown earth long-term localization experimental field.The experimental results showed that compared with the baseline,the contents of the water soluble Cu,the weak acid soluble Cu and residual Cu decreased,the contents of oxidizable Cu and reducible Cu decreased in fertilizer area while in organic fertilizer area the trend was opposite;except residual Zn,the contents of other forms increased.The distributions of Cu forms were different in different treatments in topsoil(0-20 cm),residual Zn was the main forms.As for the spatial distribution,with the deepen of soil,the contents of the weak acid soluble,oxidizable and reducible Cu,Zn reduced.Reducible Cu gave the greatest contribution to available Cu and oxidizable Zn gave the greatest contribution to available Zn.%采用改进的BCR连续提取法,对沈阳农业大学棕壤肥料长期定位试验地31年不同施肥处理土壤铜和锌含量变化及其空间变异规律进行研究。结果表明:与试验前相比,耕层(0-20cm)土壤各处理水溶态铜、弱酸溶态铜和残渣态铜含量都有不同程度的减少,可还原态铜和可氧化态铜含量在化肥区有所降低,在有机肥区有所增加;残渣态锌含量明显减少,其他形态锌含量有不同程度的增加。耕层各形态铜分布趋势因处理不同而不同,锌以残渣态为主。在空间分布上,2种元素弱酸溶态、可还原态和可氧化态含量都是随土层的加深而减少。可氧化态铜与有效态铜关系最密切;可还原态锌对有效态锌的贡献最大。

  9. Consequences of long-term hyperparathyroidism

    NARCIS (Netherlands)

    Graal, M B; Wolffenbuttel, B H

    1998-01-01

    We describe a young woman with long-term untreated hyperparathyroidism with a superimposed vitamin D deficiency and an extremely decreased bone mineral density that was complicated by a vertebral fracture. Despite pretreatment with intravenous pamidronate and short-term vitamin D supplementation, se

  10. Long-term prevention of diabetic nephropathy

    DEFF Research Database (Denmark)

    Schjoedt, K J; Hansen, H P; Tarnow, L

    2008-01-01

    AIMS/HYPOTHESIS: In type 1 diabetic patients with microalbuminuria not receiving antihypertensive treatment, an increase in urinary AER (UAER) of 6-14%/year and a risk of developing diabetic nephropathy (DN) of 3-30%/year have been reported. We audited the long-term effect of blocking the renin-a...

  11. Long Term Transfer Effect of Metaphoric Allusion.

    Science.gov (United States)

    Hayes, David A.; Mateja, John A.

    A study was conducted to investigate the long term transfer effect of metaphoric allusion used to clarify unfamiliar subject matter. Forty-nine high school students were given unfamiliar prose materials variously augmented by metaphoric allusion. The subjects' immediate performance on a transfer task was compared to their performance on an…

  12. Long-Term Memory and Learning

    Science.gov (United States)

    Crossland, John

    2011-01-01

    The English National Curriculum Programmes of Study emphasise the importance of knowledge, understanding and skills, and teachers are well versed in structuring learning in those terms. Research outcomes into how long-term memory is stored and retrieved provide support for structuring learning in this way. Four further messages are added to the…

  13. Long-Term Stability of Social Participation

    Science.gov (United States)

    Hyyppa, Markku T.; Maki, Juhani; Alanen, Erkki; Impivaara, Olli; Aromaa, Arpo

    2008-01-01

    The long-term stability of social participation was investigated in a representative urban population of 415 men and 579 women who had taken part in the nationwide Mini-Finland Health Survey in the years 1978-1980 and were re-examined 20 years later. Stability was assessed by means of the following tracking coefficients: kappa, proportion of…

  14. The long term characteristics of greenschist

    Science.gov (United States)

    Jang, Bo-An

    2016-04-01

    The greenschist in the Jinping II Hydropower Station in southwest China exhibits continuous creep behaviour because of the geological conditions in the region. This phenomenon illustrates the time-dependent deformation and progressive damage that occurs after excavation. In this study, the responses of greenschist to stress over time were determined in a series of laboratory tests on samples collected from the access tunnel walls at the construction site. The results showed that the greenschist presented time-dependent behaviour under long-term loading. The samples generally experienced two stages: transient creep and steady creep, but no accelerating creep. The periods of transient creep and steady creep increased with increasing stress levels. The long-term strength of the greenschist was identified based on the variation of creep strain and creep rate. The ratio of long-term strength to conventional strength was around 80% and did not vary much with confining pressures. A quantitative method for predicting the failure period of greenschist, based on analysis of the stress-strain curve, is presented and implemented. At a confining pressure of 40 MPa, greenschist was predicted to fail in 5000 days under a stress of 290 MPa and to fail in 85 days under the stress of 320 MPa, indicating that the long-term strength identified by the creep rate and creep strain is a reliable estimate.

  15. Pituitary diseases : long-term psychological consequences

    NARCIS (Netherlands)

    Tiemensma, Jitske

    2012-01-01

    Nowadays, pituitary adenomas can be appropriately treated, but patients continue to report impaired quality of life (QoL) despite long-term remission or cure. In patients with Cushing’s disease, Cushing’s syndrome or acromegaly, doctors should be aware of subtle cognitive impairments and the

  16. A technique for long term continent gastrostomy.

    Science.gov (United States)

    Locker, D L; Foster, J E; Craun, M L; Torma, M J

    1985-01-01

    The use of the continent gastrostomy described herein offers several advantages: 1, the elimination of an indwelling catheter; 2, prevention of soiling at skin level; 3, long term access to the normal gastrointestinal track for alimentation without fear of tube erosion; 4, little compromise to gastric volume, and 5, ease of stoma care. We recommend this operation in instances when long term tube feedings are indicated either because of damage to the central nervous system or as a palliative treatment for patients with higher obstructing gastrointestinal malignant disease. The procedure may also be useful for patients in whom esophagogastric continuity has been interrupted (surgically or traumatically) and in whom reconstruction of the gastrointestinal tract would not seem feasible within a three to six month interval.

  17. Long-term opioid therapy in Denmark

    DEFF Research Database (Denmark)

    Birke, H; Ekholm, O; Sjøgren, P

    2017-01-01

    BACKGROUND: Longitudinal population-based studies of long-term opioid therapy (L-TOT) in chronic non-cancer pain (CNCP) patients are sparse. Our study investigated incidence and predictors for initiating L-TOT and changes in self-rated health, pain interference and physical activities in long......-term opioid users. METHODS: Data were obtained from the national representative Danish Health and Morbidity Surveys and The Danish National Prescription Registry. Respondents with no dispensed opioids the year before the survey were followed from 2000 and from 2005 until the end of 2012 (n = 12...... defined as those who were dispensed at least one opioid prescription in six separate months within a year. RESULTS: The incidence of L-TOT was substantially higher in CNCP patients at baseline than in others (9/1000 vs. 2/1000 person-years). Smoking behaviour and dispensed benzodiazepines were...

  18. Case presentation: long-term treatment.

    Science.gov (United States)

    Glucksman, Myron L

    2013-01-01

    The long-term (14 years) psychodynamic psychotherapy and pharmacotherapy of a depressed, suicidal, self-mutilating female patient is described. Her diagnoses included Chronic Posttraumatic Stress Disorder, Borderline Personality Disorder, and Recurrent Major Depression. Treatment was punctuated with repeated hospitalizations for self-mutilation (cutting) and suicidal ideation. A major determinant for her psychopathology was sexual abuse by her father from ages 6 to 14. This resulted in feelings of guilt and rage that she repressed and acted out through self-mutilating and suicidal behavior. A prolonged negative transference gradually became ambivalent, then positive. This was associated with her internalization of the healing qualities of the therapeutic relationship. She also gained insight into the reasons for her need to punish herself. Her initial self-representation as unworthy and bad was transformed into perceiving herself as a worthwhile, loving person. This case illustrates the role of long-term treatment for a complex, life-threatening, psychiatric disorder.

  19. Long-Term Hearing Results After Ossiculoplasty.

    Science.gov (United States)

    Cox, Matthew D; Trinidade, Aaron; Russell, James Shep; Dornhoffer, John L

    2017-04-01

    To determine if the OOPS index is predictive of long-term hearing results after ossiculoplasty. Case series with retrospective chart review. Tertiary care otology practice. Adult and pediatric patients (3-88 years of age). Ossiculoplasty with cartilage tympanoplasty, with or without mastoidectomy. Primary outcome measures included short-term hearing results (pure-tone average air-bone gap [PTA-ABG] measured between 60 days and 1 year after surgery), long-term hearing results (PTA-ABG measured ≥5 years after surgery), and the rate of successful ABG closure to ≤20 dB. Secondary measures included the need for revision surgery, delayed tympanic membrane graft failure, worsening conductive hearing loss (after an initially satisfactory hearing result), and recurrence of cholesteatoma. There was no significant difference between adults and children for short-term hearing results (average post-op PTA-ABG was 18.9 dB vs. 19.8 dB, respectively; p = 0.544), long-term hearing results (average final PTA-ABG was 19.3 dB vs. 19.4 dB, respectively; p = 0.922), or rate of ABG closure to less than 20 dB (63.1% vs. 58.0%, p = 0.282). Spearman's rank-order correlation (ρ) identified a strong positive correlation between OOPS index score and average post-operative PTA-ABG (ρ = 0.983; p hearing outcomes in adult and pediatric patients undergoing ossiculoplasty in both the short term and the long term.

  20. Timber joints under long-term loading

    DEFF Research Database (Denmark)

    Feldborg, T.; Johansen, M.

    This report describes tests and results from stiffness and strength testing of splice joints under long-term loading. During two years of loading the spicimens were exposed to cyclically changing relative humidity. After the loading period the specimens were short-term tested. The connectors were...... integral nail-plates and nailed steel and plywood gussets. The report is intended for designers and researchers in timber engineering....

  1. Cutaneous oxalosis after long-term hemodialysis.

    Science.gov (United States)

    Abuelo, J G; Schwartz, S T; Reginato, A J

    1992-07-01

    A 27-year-old woman undergoing long-term hemodialysis developed cutaneous calcifications on her fingers. A skin biopsy specimen showed that the deposits were calcium oxalate. To our knowledge, only one previous article has reported pathologic and crystallographic studies on calcifications of the skin resulting from dialysis oxalosis. We speculate that vitamin C supplements, liberal tea consumption, an increased serum ionized calcium concentration, and the long duration of hemodialysis contributed to the production of these deposits.

  2. Long term evolution 4G and beyond

    CERN Document Server

    Yacoub, Michel; Figueiredo, Fabrício; Tronco, Tania

    2016-01-01

    This book focus on Long Term Evolution (LTE) and beyond. The chapters describe different aspects of research and development in LTE, LTE-Advanced (4G systems) and LTE-450 MHz such as telecommunications regulatory framework, voice over LTE, link adaptation, power control, interference mitigation mechanisms, performance evaluation for different types of antennas, cognitive mesh network, integration of LTE network and satellite, test environment, power amplifiers and so on. It is useful for researchers in the field of mobile communications.

  3. Consequences of long-term hyperparathyroidism.

    Science.gov (United States)

    Graal, M B; Wolffenbuttel, B H

    1998-07-01

    We describe a young woman with long-term untreated hyperparathyroidism with a superimposed vitamin D deficiency and an extremely decreased bone mineral density that was complicated by a vertebral fracture. Despite pretreatment with intravenous pamidronate and short-term vitamin D supplementation, severe and long-standing hypocalcaemia ('hungry bone syndrome') developed after parathyroidectomy. We discuss the consequences of hyperparathyroidism, especially the effects on bone, the complications of parathyroidectomy and the possibilities of preoperative treatment with bisphosphonates.

  4. Long-term behaviour of GRP pipes

    OpenAIRE

    Faria, H; A Vieira; Reis, J; Marques, A. T.; Guedes, R.M.; Ferreira, A. J. M.

    2005-01-01

    The main objective of the research programme /1/ described is the study of creep and relaxation behaviour of glass-rein forced thermosetting (GRP) pipes, in order to find alternative methods to predict the long-term properties, rendering a considerable reduction of the time needed for testing and assuring, as far as possible, equivalent reliability when compared to the existing methods. Experimental procedures were performed and are presented here, together with discussion of results, as well...

  5. Early Life Environments and Long Term Outcomes

    OpenAIRE

    Bolbocean, Corneliu

    2015-01-01

    A large literature has linked “in utero” environment to health and socio-economic outcomes in adulthood. We consider the effect of early life environments on health and skill formation outcomes. We first evaluate the impact of perinatal-neonatal level of technology at birth, which varies across delivery institutions, on the long-term neurodevelopmental outcomes of children with Cerebral Palsy. The level of technology at delivery determines the type of therapy newborns receive immediately afte...

  6. Long term economic relationships from cointegration maps

    Science.gov (United States)

    Vicente, Renato; Pereira, Carlos de B.; Leite, Vitor B. P.; Caticha, Nestor

    2007-07-01

    We employ the Bayesian framework to define a cointegration measure aimed to represent long term relationships between time series. For visualization of these relationships we introduce a dissimilarity matrix and a map based on the sorting points into neighborhoods (SPIN) technique, which has been previously used to analyze large data sets from DNA arrays. We exemplify the technique in three data sets: US interest rates (USIR), monthly inflation rates and gross domestic product (GDP) growth rates.

  7. 太湖地区长期不同施肥水稻土N2和CO2固定细菌群落结构的特征与差异%Community structure characters and differences of N2-fixing and CO2-fixing bacteria under long-term fertilization in paddy soils of Taihu Lake region, China

    Institute of Scientific and Technical Information of China (English)

    靳振江; 潘根兴; 刘晓雨; 李恋卿

    2013-01-01

    Both C02-fixing and N2-fixing bacteria are important microbes involved in soil carbon and nitrogen cycles, respectively. It is helpful for us to know the effect of fertilization on carbon and nitrogen cycles in farmland soils and to analyze the relationship between the soil organic carbon (SOC) and community structures of N2-fixing and CO2-fixing bacteria. The topsoil (0-20 cm) samples were collected from a paddy field under a long-term different fertilization trials initiated in 1987 from Taihu Lake region, China. There were four treatments, no fertilizer application (NF) , application of NPK fertilizers only (CF) , combined application of NPK fertilizers and pig manure (CFM) and combined application of NPK fertilizers and straw return ( CFS). Community structures were analyzed using PCR-DGGE and real-time PCR with nifH gene and cbbLR gene as indicators of N2-fixing and CO2-fixing bacteria, respectively. Cloning forming unit (CFU) of autotrophic azotobacter was evaluated using plating colony-counting method. Nitrogenase activity was detected using acetylene reduction method as well. The results show that the abundances of nifH gene in the CF treatment, CFM treatment and CFS treatment are increased by 213% , 1079 % and 344% , respectively compared with the NF treatment, and CFUs of autotrophic azotobacter are increased by 58% , 66% and 106%. Nitrogenase activities in CF and CFM treatments are significantly higher than those in NF and CFS treatments. The diversity of cbbLR gene is increased after the fertilizer application. The abundances of cbbLR gene in the CF treatment, CFM treatment and CFS treatment are increased by 465% , 1827% and 758% , respectively compared with the NF treatment. The statistical analysis reveals there are significant correlations between the two abundances and soil nutrient richness normalized ( SNRN) of SOC, total nitrogen (TN) and total phosphorus (TP) and between the CFU of autotrophic azotobacter and SOC. These results indicate that

  8. An international review of the long-term care workforce: policies and shortages.

    Science.gov (United States)

    Hussein, Shereen; Manthorpe, Jill

    2005-01-01

    The developed world's population is aging, due to trends of increased life expectancies and decreased fertility rates. These trends are predicted to increase demand on long-term care services. At the same time, the long-term care workforce is in shortage in most of the developed world. Moreover, such shortages are expected to increase due to parallel socio-demographic factors. The increase in demand for longterm care, coupled with shortage in supply of care workers, has promoted some attention from policymakers. The current paper provides an international review of institutional arrangements for long-term care in different developed countries and in particular explores different strategies used or proposed to resolve the shortage in the long-term care workforce.

  9. Long-term Fertilization Determining Ammonia-oxidizing Organism Abundance and Distribution in Dry Highland Soil of Loess Plateau%长期施肥对旱地土壤中氨氧化微生物丰度和分布的影响

    Institute of Scientific and Technical Information of China (English)

    辛亮; 武传东; 曲东

    2012-01-01

    采用基于氨单加氧酶基因(amoA)的荧光定量PCR技术,以黄土高原旱地土为材料,研究长期施肥对土壤氨氧化细菌和氨氧化古菌丰度的影响,并分析环境因素与氨氧化菌丰度的关系.以不施肥土壤为对照(CK),设置3个施肥处理,分别为单施磷肥(P),氮、磷共施(NP)和氮、磷、有机肥共施(NPM)3个处理.结果表明,不同处理氨氧化菌amoA基因拷贝数为1.326×106~1.886×106 g1,各处理间氨氧化细菌丰度差异不显著;氨氧化古菌的arch-amoA基因拷贝数为1.329×106~4.510×106 g-1,表现为处理NPM> NP>CK>P,NPM处理为对照的3.314倍,二者呈现显著性差异.采用DCCA法对4个处理进行环境相似度分类,结果显示,P和NPM处理、CK和NP处理分别构成了2个相似类群;4个处理和12个环境因子的关联(CCA)分析表明,不同处理中的氨氧化微生物活跃度以及氨氧化过程强度表现为处理NMP>NP>CK>P;不同环境因子和不同施肥处理生境相似度分布存在不同的关系,其中反映氨氧化过程的硝态氮含量、氨氧化细菌和氨氧化古菌丰度,以及代表微生物生长主要环境因素的pH值、含水量、全氮和有机碳含量与不同施肥处理导致的生境相似度的分布关系最为紧密.%Real-time PCR with primers targeting Ammonia monooxygenase subunit A gene iamoA) was performed to quantify abundance of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing ar-chaea (AOA) in dry highland soilt long-term fertilized, from Loess Plateau. We also investigated the relationship between environmental factors and abundance of ammonia-oxidizing organism. The treatments were no fertilizer (CK), phosphate (P), nitrogen/phosphate fertilizers (NP), and NP combined with organic fertilizer (NPM). We found that fertilization caused no significant difference on the amoA gene copy numbers of AOB arranging from 1, 326× 106 to 1. 886 × 106 copies · g-1 dry soil. In contrast, abundance of

  10. Water cycle investigations in Hungarian forest ecosystems

    Institute of Scientific and Technical Information of China (English)

    Judit Sitkey

    2006-01-01

    From the biological point of view the value of autotrophy plant association is determined by the carbon fixation and the carbon cycle. Among the plant associations of Hungary, forest has the largest biological carbon fixation and carbon cycle. In general,the annual water cycle is the key factor in the organic material production of the Hungarian forests. The most intensive water consumption and organic material production take place from May till July, which period is named main water consumption and respectively main growing period. In Hungary the categories of the forest climate are characterized by main tree species and based on the forest climate covers 8% of the forest area, hornbeam-oak forest climate covers 22%, sessile oak-Turkey oak forest climate covers48% and forest steppe climate covers 22%. Partly in the frame of ICP-Forests, the Department of Ecology in the Forest Research Institute carries out long term, complex ecophysiological investigations on several sample plots (so-called basic plots) throughout the whole country. The organic material production (growth), the nutrient and water cycle, the measurements of air pollutants and meteorological parameters, as well as chemical analyses are all part of the investigations. As a comparison the figure of two basic plotsforest steppe climate in the hydrological year of 2001-2002. In the Hungarian forest 60%-70% of the precipitation is used for interception, evaporation, and in the vegetation season, for the transpiration both in beech and forest steppe climate. From other point of view, only 30%-40% of the open air precipitation infiltrates into the soil and can be utilized by the forest.

  11. Long-Term Recency in Anterograde Amnesia.

    Directory of Open Access Journals (Sweden)

    Deborah Talmi

    Full Text Available Amnesia is usually described as an impairment of a long-term memory (LTM despite an intact short-term memory (STM. The intact recency effect in amnesia had supported this view. Although dual-store models of memory have been challenged by single-store models based on interference theory, this had relatively little influence on our understanding and treatment of amnesia, perhaps because the debate has centred on experiments in the neurologically intact population. Here we tested a key prediction of single-store models for free recall in amnesia: that people with amnesia will exhibit a memory advantage for the most recent items even when all items are stored in and retrieved from LTM, an effect called long-term recency. People with amnesia and matched controls studied, and then free-recalled, word lists with a distractor task following each word, including the last (continual distractor task, CDFR. This condition was compared to an Immediate Free Recall (IFR, no distractors and a Delayed Free Recall (DFR, end-of-list distractor only condition. People with amnesia demonstrated the full long-term recency pattern: the recency effect was attenuated in DFR and returned in CDFR. The advantage of recency over midlist items in CDFR was comparable to that of controls, confirming a key prediction of single-store models. Memory deficits appeared only after the first word recalled in each list, suggesting the impairment in amnesia may emerge only as the participant's recall sequence develops, perhaps due to increased susceptibility to output interference. Our findings suggest that interference mechanisms are preserved in amnesia despite the overall impairment to LTM, and challenge strict dual-store models of memory and their dominance in explaining amnesia. We discuss the implication of our findings for rehabilitation.

  12. Long-Term Recency in Anterograde Amnesia.

    Science.gov (United States)

    Talmi, Deborah; Caplan, Jeremy B; Richards, Brian; Moscovitch, Morris

    2015-01-01

    Amnesia is usually described as an impairment of a long-term memory (LTM) despite an intact short-term memory (STM). The intact recency effect in amnesia had supported this view. Although dual-store models of memory have been challenged by single-store models based on interference theory, this had relatively little influence on our understanding and treatment of amnesia, perhaps because the debate has centred on experiments in the neurologically intact population. Here we tested a key prediction of single-store models for free recall in amnesia: that people with amnesia will exhibit a memory advantage for the most recent items even when all items are stored in and retrieved from LTM, an effect called long-term recency. People with amnesia and matched controls studied, and then free-recalled, word lists with a distractor task following each word, including the last (continual distractor task, CDFR). This condition was compared to an Immediate Free Recall (IFR, no distractors) and a Delayed Free Recall (DFR, end-of-list distractor only) condition. People with amnesia demonstrated the full long-term recency pattern: the recency effect was attenuated in DFR and returned in CDFR. The advantage of recency over midlist items in CDFR was comparable to that of controls, confirming a key prediction of single-store models. Memory deficits appeared only after the first word recalled in each list, suggesting the impairment in amnesia may emerge only as the participant's recall sequence develops, perhaps due to increased susceptibility to output interference. Our findings suggest that interference mechanisms are preserved in amnesia despite the overall impairment to LTM, and challenge strict dual-store models of memory and their dominance in explaining amnesia. We discuss the implication of our findings for rehabilitation.

  13. Effects of long-term N fertilizer application and liming on nitrification and ammonia oxidizers in acidic soils%长期施加氮肥及氧化钙调节对酸性土壤硝化作用及氨氧化微生物的影响

    Institute of Scientific and Technical Information of China (English)

    张苗苗; 王伯仁; 李冬初; 贺纪正; 张丽梅

    2015-01-01

    High levels of N fertilization and acid deposition could cause soil acidification directly and indirectly. The nitrogen cycle, especially nitrification, makes a great contribution to the acidification of agricultural soils across China, which further leads to the mobilization of potentially toxic metals such as aluminum ( Al ) and manganese ( Mn ) and decerases crop yields. Chemicals ( e. g., CaO) are amended as soil conditioners to relieve soil acidification. Ammonia oxidation, the rate-limiting step in the nitrification process, is driven by ammonia-oxidizing bacteria ( AOB) and ammonia-oxidizing archaea ( AOA) . Increasing evidence demonstrates that pH is one of the most important factors determining the niche separation of AOA and AOB, and AOA play the more important role in nitrification of acidic soils. However, abundant AOB have been detected in acidic soils but little is known about their ecological function. In this study, the effects of long-term N fertilization practices and liming on nitrification and ammonia oxidizers in acidic soils were investigated using quantitative PCR and DGGE methods combined with soil physiochemical analysis. Compared with a previous study conducted 6 years ago at the same site, N fertilizer application without liming further decreased soil pH (3.35—3.47) and potential nitrification rate (PNR) (0.02—0.14 μg NO-2-N g-1 soil h-1), while 2 years liming alleviated soil acidification (pH 4.10—4.46) and increased PNR (0.22—0.34μg NO-2-N g-1 soil h-1) significantly. There was a significantly positive correlation between soil pH and PNR, indicating the increase in soil pH via liming had positive effects on nitrification in acidic soils. AOA amoA gene copy numbers ( 7. 40 × 107—4. 08 × 108 copies/g ) were significantly higher than their counterpart AOB (1.67 × 106—2.57 × 107 copies/g) in soils that received different chemical N fertilizers. Ratios of AOA and AOB amoA gene abundance ranged between 10. 9 and 44. 3

  14. Phosphorus and root distribution and corn growth as related to long-term tillage systems and fertilizer placement Distribuição de fósforo e raízes e crescimento do milho em sistemas de manejo do solo e modos de aplicação de fertilizante no longo prazo

    Directory of Open Access Journals (Sweden)

    Sérgio Ely Valadão Gigante de Andrade Costa

    2009-10-01

    Full Text Available Soil and fertilizer management during cultivation can affect crop productivity and profitability. Long-term experiments are therefore necessary to determine the dynamics of nutrient and root distribution as related to soil profile, as well as the effects on nutrient uptake and crop growth. An 18-year experiment was conducted at the Federal University of Rio Grande do Sul State (UFRGS, in Eldorado do Sul, Brazil, on Rhodic Paleudult soil. Black oat and vetch were planted in the winter and corn in the summer. The soil management methods were conventional, involving no-tillage and strip tillage techniques and broadcast, row-and strip-applied fertilizer placement (triple superphosphate. Available P (Mehlich-1 and root distribution were determined in soil monoliths during the corn grain filling period. Corn shoot dry matter production and P accumulation during the 2006/2007 growing season were determined and the efficiency of P utilization calculated. Regardless of the degree of soil mobilization, P and roots were accumulated in the fertilized zone with time, mainly in the surface layer (0-10 cm. Root distribution followed P distribution for all tillage systems and fertilizer treatments. Under no-tillage, independent of the fertilizer placement, the corn plants developed more roots than in the other tillage systems. Although soil tillage systems and fertilizer treatments affected P and root distribution throughout the soil profile, as well as P absorption and corn growth, the efficiency of P utilization was not affected.O manejo do solo e de fertilizantes ao longo do tempo de cultivo pode contribuir para o rendimento e lucratividade das lavouras. Há, então, a necessidade de se ter e avaliar experimentos de longo prazo para que se consiga entender a dinâmica da distribuição de nutrientes e raízes no perfil do solo e seu efeito na absorção de nutrientes e no crescimento e desenvolvimento da cultura. Foi utilizado um experimento de 18 anos de

  15. Long-term policy on gas composition

    Energy Technology Data Exchange (ETDEWEB)

    Verhagen, M.J.M.

    2012-03-13

    This letter sets out the policy of the Dutch cabinet on the long-term change to the composition of low calorific gas that is distributed via the public gas grid. The title of a separate attachment to this letter is 'The composition of low calorific gas in the more distant future and the requirements for gas appliances covered by the Gas Appliances Directive'. The attachment sets out the composition of low calorific gas as network operators can distribute it via the public gas grid from 2021 (or from a later date). This relates to the changes in the 'exit specification' of the gas.

  16. Safety of long-term PPI therapy

    DEFF Research Database (Denmark)

    Reimer, Christina

    2013-01-01

    Proton pump inhibitors have become the mainstay of medical treatment of acid-related disorders. Long-term use is becoming increasingly common, in some cases without a proper indication. A large number of mainly observational studies on a very wide range of possible associations have been published...... is based on a relevant indication. The concern for complications should primarily be directed at elderly, malnourished with significant co-morbidity. In this population an increased risk for enteric infections, fractures and nutritional deficiencies might have clinical consequences and should lead...

  17. Long-term space flights - personal impressions

    Science.gov (United States)

    Polyakov, V. V.

    During a final 4-month stage of a 1-year space flight of cosmonauts Titov and Manarov, a physician, Valery Polyakov was included on a crew for the purpose of evaluating their health, correcting physical status to prepare for the spacecraft reentry and landing operations. The complex program of scientific investigations and experiments performed by the physician included an evaluation of adaptation reactions of the human body at different stages of space mission using clinicophysiological and biochemical methods; testing of alternative regimes of exercise and new countermeasures to prevent an unfavourable effect of long-term weightlessness.

  18. The long term stability of lidar calibrations

    DEFF Research Database (Denmark)

    Courtney, Michael; Gayle Nygaard, Nicolai

    Wind lidars are now used extensively for wind resource measurements. One of the requirements for the data to be accepted in support of project financing (so-called ‘banka-bility’) is to demonstrate the long-term stability of lidar cali-brations. Calibration results for six Leosphere WindCube li-dars......-ters pertaining in the different calibration periods. This is supported by sliding-window analyses of one lidar at one location where the same order of variation is observed as between pre-service and post-service calibrations....

  19. Long-term effects of sibling incest.

    Science.gov (United States)

    Daie, N; Witztum, E; Eleff, M

    1989-11-01

    Although sexual abuse of children is recognized as a serious problem, sibling incest has received relatively little attention. A distinction has been made between power-oriented sibling incest and nurturance-oriented incest. The authors review the relevant literature and present four clinical examples. The cases illustrate the broad range of sibling incest and demonstrate its effects, including the long-term consequences for the perpetrator. Lasting difficulties in establishing and maintaining close relationships, especially sexual ones, are prominent features of each case. Without denying the occurrences of benign sex-play between siblings, the authors emphasize exploitation and abuse as pathogenic aspects of sibling incest.

  20. Long Term Analysis for the BAM device

    Science.gov (United States)

    Bonino, D.; Gardiol, D.

    2011-02-01

    Algorithms aimed at the evaluation of critical quantities are based on models with many parameters, which values are estimated from data. The knowledge, with high accuracy, of these values and the control of their temporal evolution are important features. In this work, we focus on the latter subject, and we show a proposed pipeline for the BAM (Basic Angle Monitoring) Long Term Analysis, aimed at the study of the calibration parameters of the BAM device and of the Basic Angle variation, searching for unwanted trends, cyclic features, or other potential unexpected behaviours.

  1. Long-Term Wind Power Variability

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Y. H.

    2012-01-01

    The National Renewable Energy Laboratory started collecting wind power data from large commercial wind power plants (WPPs) in southwest Minnesota with dedicated dataloggers and communication links in the spring of 2000. Over the years, additional WPPs in other areas were added to and removed from the data collection effort. The longest data stream of actual wind plant output is more than 10 years. The resulting data have been used to analyze wind power fluctuations, frequency distribution of changes, the effects of spatial diversity, and wind power ancillary services. This report uses the multi-year wind power data to examine long-term wind power variability.

  2. Terminating a long-term clinical trial.

    Science.gov (United States)

    Klimt, C R

    1981-05-01

    Long-term clinical trials often include more than one active treatment group. These may be discontinued independently if found to be ineffective or possibly harmful. Certain subgroups of patients may be discovered, in the course of a clinical trial, who do not respond satisfactorily and are, therefore, excluded during the course of a trial. Yet another kind of termination comes when we have a therapeutic breakthrough or when hope has to be abandoned for demonstrating beneficial effects for one, several, or all treatments included in a trial. Examples from the authors' experience are presented, as are successful and unsuccessful techniques in managing terminations of various types.

  3. Atributos químicos do solo influenciados por sucessivas aplicações de dejetos suínos em áreas agrícolas de Santa Catarina Long-term swine manure fertilization and its effects on soil chemical properties in santa catarina, southern Brazil

    Directory of Open Access Journals (Sweden)

    Eloi Erhard Scherer

    2010-08-01

    may have a negative impact on the environment when inadequately used. The aim of this work was to evaluate changes in properties of soils under no-till grain production and long-term swine manure fertilization. Soil samples from three representative soils types (Oxisol, Inceptisol and Leptosol from Western Santa Catarina, Southern Brazil, were collected under no-tillage cultivation and surface application of swine manure for about 15 years and over 20 years. Samples from areas treated with mineral fertilizer and unfertilized controls (under forest vegetation were also collected from seven soil layers (0-5, 5-10, 10-20, 20-30, 40-50, 70-80, and 100-110 cm to evaluate soil organic matter content and available P, K, Cu, and Zn. Long-term swine manure application caused nutrient accumulation (P, K, Cu and Zn in the top soil layer, mainly in the top 5 cm of soil. Soil organic matter was not affected by manure application. In general, the annual manure applications did not affect the chemical properties of the subsoil. In Leptosol and Inceptisol, however, increased P concentrations were found in the 40-50 cm and 70-80 cm soil layers, indicating a greater potential for P loss in these soils. Exchangeable Zn and Cu was accumulated mainly in the top 10 cm of the Oxisol and in the top 20 cm of the Inceptisol and Leptosol. The accumulation of nutrients in the top soil layer (0-5 cm indicated a greater potential for nutrient loss than in soils treated with conventional mineral fertilizer.

  4. Long term effects of Escherichia coli mastitis.

    Science.gov (United States)

    Blum, Shlomo E; Heller, Elimelech D; Leitner, Gabriel

    2014-07-01

    Escherichia coli is one of the most frequently diagnosed causes of bovine mastitis, and is typically associated with acute, clinical mastitis. The objective of the present study was to evaluate the long term effects of intramammary infections by E. coli on milk yield and quality, especially milk coagulation. Twenty-four Israeli Holstein cows diagnosed with clinical mastitis due to intramammary infection by E. coli were used in this study. Mean lactation number, days in milk (DIM) and daily milk yield (DMY) at the time of infection was 3.3 ± 1.3, 131.7 days ± 78.6 and 45.7 L ± 8.4, respectively. DMY, milk constituents, somatic cells count (SCC), differential leukocytes count and coagulation parameters were subsequently assessed. Two patterns of inflammation were identified: 'short inflammation', characterized by 15% decrease in DMY and >30 days to reach a new maximum DMY (n = 19). The estimated mean loss of marketable milk during the study was 200 L/cow for 'short inflammation' cases, and 1,500 L/cow for 'long inflammation' ones. Significant differences between 'short' and 'long inflammation' effects were found in almost all parameters studied. Long-term detrimental effects on milk quality were found regardless of clinical or bacteriological cure of affected glands.

  5. Long term perfusion system supporting adipogenesis.

    Science.gov (United States)

    Abbott, Rosalyn D; Raja, Waseem K; Wang, Rebecca Y; Stinson, Jordan A; Glettig, Dean L; Burke, Kelly A; Kaplan, David L

    2015-08-01

    Adipose tissue engineered models are needed to enhance our understanding of disease mechanisms and for soft tissue regenerative strategies. Perfusion systems generate more physiologically relevant and sustainable adipose tissue models, however adipocytes have unique properties that make culturing them in a perfusion environment challenging. In this paper we describe the methods involved in the development of two perfusion culture systems (2D and 3D) to test their applicability for long term in vitro adipogenic cultures. It was hypothesized that a silk protein biomaterial scaffold would provide a 3D framework, in combination with perfusion flow, to generate a more physiologically relevant sustainable adipose tissue engineered model than 2D cell culture. Consistent with other studies evaluating 2D and 3D culture systems for adipogenesis we found that both systems successfully model adipogenesis, however 3D culture systems were more robust, providing the mechanical structure required to contain the large, fragile adipocytes that were lost in 2D perfused culture systems. 3D perfusion also stimulated greater lipogenesis and lipolysis and resulted in decreased secretion of LDH compared to 2D perfusion. Regardless of culture configuration (2D or 3D) greater glycerol was secreted with the increased nutritional supply provided by perfusion of fresh media. These results are promising for adipose tissue engineering applications including long term cultures for studying disease mechanisms and regenerative approaches, where both acute (days to weeks) and chronic (weeks to months) cultivation are critical for useful insight.

  6. Long-term environmental behaviour of radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Brechignac, F.; Moberg, L.; Suomela, M

    2000-04-01

    The radioactive pollution of the environment results from the atmospheric nuclear weapons testing (during the mid-years of twentieth century), from the development of the civilian nuclear industry and from accidents such as Chernobyl. Assessing the resulting radiation that humans might receive requires a good understanding of the long-term behaviour of radionuclides in the environment. This document reports on a joint European effort to advance this understanding, 3 multinational projects have been coordinated: PEACE, EPORA and LANDSCAPE. This report proposes an overview of the results obtained and they are presented in 6 different themes: (i) redistribution in the soil-plant system, (ii) modelling, (iii) countermeasures, (iv) runoff (v) spatial variations, and (vi) dose assessment. The long term behaviour of the radionuclides {sup 137}Cs, {sup 90}Sr and {sup 239-240}Pu is studied through various approaches, these approaches range from in-situ experiments designed to exploit past contamination events to laboratory simulations. A broad scope of different ecosystems ranging from arctic and boreal regions down to mediterranean ones has been considered. (A.C.)

  7. Long term testing of PSI-membranes

    Energy Technology Data Exchange (ETDEWEB)

    Huslage, J.; Brack, H.P.; Geiger, F.; Buechi, F.N.; Tsukada, A.; Scherer, G.G. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    Long term tests of PSI membranes based on radiation-grafted FEP and ETFE films were carried out and FEP-based membranes were evaluated by monitoring the in-situ membrane area resistance measured by a current pulse method. By modifying our irradiation procedure and using the double crosslinking concept we obtain reproducible membrane cell lifetimes (in term of in-situ membrane resistance) of greater than 5000 hours at 60-65{sup o}C. Preliminary tests at 80-85{sup o}C with lifetimes of greater than 2500 demonstrate the potential long term stability of PSI proton exchange membranes based on FEP over the whole operating temperature range of low-temperature polymer electrolyte fuel cells. Radiation grafted PSI membranes based on ETFE have better mechanical properties than those of the FEP membranes. Mechanical properties are particularly important in large area cells and fuel cell stacks. ETFE membranes have been tested successfully for approximately 1000 h in a 2-cell stack (100 cm{sup 2} active area each cell). (author) 4 figs., 4 refs.

  8. Long Term Changes in the Polar Vortices

    Science.gov (United States)

    Braathen, Geir O.

    2016-04-01

    As the amount of halogens in the stratosphere is slowly declining and the ozone layer slowly recovers it is of interest to see how the meteorological conditions in the vortex develop over the long term since such changes might alter the foreseen ozone recovery. In conjunction with the publication of the WMO Antarctic and Arctic Ozone Bulletins, WMO has acquired the ERA Interim global reanalysis data set for several meteorological parameters. This data set goes from 1979 - present. These long time series of data can be used for several useful studies of the long term development of the polar vortices. Several "environmental indicators" for vortex change have been calculated, and a climatology, as well as trends, for these parameters will be presented. These indicators can act as yardsticks and will be useful for understanding past and future changes in the polar vortices and how these changes affect polar ozone depletion. Examples of indicators are: vortex mean temperature, vortex minimum temperature, vortex mean PV, vortex "importance" (PV*area), vortex break-up time, mean and maximum wind speed. Data for both the north and south polar vortices have been analysed at several isentropic levels from 350 to 850 K. A possible link between changes in PV and sudden stratospheric warmings will be investigated, and the results presented. The unusual meteorological conditions of the 2015 south polar vortex and the 2010/11 and 2015/16 north polar vortices will be compared to other recent years.

  9. Climate Predictability and Long Term Memory

    Science.gov (United States)

    Zhu, X.; Blender, R.; Fraedrich, K.; Liu, Z.

    2010-09-01

    The benefit of climate Long Term Memory (LTM) for long term prediction is assessed using data from a millennium control simulation with the atmosphere ocean general circulation model ECHAM5/MPIOM. The forecast skills are evaluated for surface temperature time series at individual grid points. LTM is characterised by the Hurst exponent in the power-law scaling of the fluctuation function which is determined by detrended fluctuation analysis (DFA). LTM with a Hurst exponent close to 0.9 occurs mainly in high latitude oceans, which are also characterized by high potential predictability. Climate predictability is diagnosed in terms of potentially predictable variance fractions. Explicit prediction experiments for various time steps are conducted on a grid point basis using an auto-correlation (AR1) predictor: in regions with LTM, prediction skills are beyond that expected from red noise persistence; exceptions occur in some areas in the southern oceans and over the northern hemisphere continents. Extending the predictability analysis to the fully forced simulation shows large improvement in prediction skills.

  10. Long-term Caspian Sea level change

    Science.gov (United States)

    Chen, J. L.; Pekker, T.; Wilson, C. R.; Tapley, B. D.; Kostianoy, A. G.; Cretaux, J.-F.; Safarov, E. S.

    2017-07-01

    Caspian Sea level (CSL) has undergone substantial fluctuations during the past several hundred years. The causes over the entire historical period are uncertain, but we investigate here large changes seen in the past several decades. We use climate model-predicted precipitation (P), evaporation (E), and observed river runoff (R) to reconstruct long-term CSL changes for 1979-2015 and show that PER (P-E + R) flux predictions agree very well with observed CSL changes. The observed rapid CSL increase (about 12.74 cm/yr) and significant drop ( -6.72 cm/yr) during the periods 1979-1995 and 1996-2015 are well accounted for by integrated PER flux predictions of +12.38 and -6.79 cm/yr, respectively. We show that increased evaporation rates over the Caspian Sea play a dominant role in reversing the increasing trend in CSL during the past 37 years. The current long-term decline in CSL is expected to continue into the foreseeable future, under global warming scenarios.

  11. Pediatric HIV Long-Term Nonprogressors

    Directory of Open Access Journals (Sweden)

    B. H. Rimawi

    2014-01-01

    Full Text Available Patients infected with HIV are best categorized along a continuum from rapid progressors to HIV long-term nonprogressors. Long-term nonprogressors (LTNPs are those in which AIDS develop many years after being infected with HIV, often beyond the 10-year mark, and represent 15–20% of the HIV infected patients. Many of these patients are able to control their infection and maintain undetectable viral loads for long periods of time without antiretroviral therapy. After a comprehensive literature search, we found extensive data related to HIV LTNPs in the adult population; however, very limited data was available related to LTNPs within the pediatric population. We present a case of pediatric HIV LTNPs, perinatally infected patient with undetectable viral loads, despite never receiving ART. Although there are not many instances of LTNPs among children, this child may be one, though she had intermittent viremia. She has continued to manifest serologic evidence of infection, with yearly ELISA and western blot positive tests. Based on the viral fitness studies that were performed, this case exemplifies an adolescent LTNP.

  12. Sleep facilitates long-term face adaptation.

    Science.gov (United States)

    Ditye, Thomas; Javadi, Amir Homayoun; Carbon, Claus-Christian; Walsh, Vincent

    2013-10-22

    Adaptation is an automatic neural mechanism supporting the optimization of visual processing on the basis of previous experiences. While the short-term effects of adaptation on behaviour and physiology have been studied extensively, perceptual long-term changes associated with adaptation are still poorly understood. Here, we show that the integration of adaptation-dependent long-term shifts in neural function is facilitated by sleep. Perceptual shifts induced by adaptation to a distorted image of a famous person were larger in a group of participants who had slept (experiment 1) or merely napped for 90 min (experiment 2) during the interval between adaptation and test compared with controls who stayed awake. Participants' individual rapid eye movement sleep duration predicted the size of post-sleep behavioural adaptation effects. Our data suggest that sleep prevented decay of adaptation in a way that is qualitatively different from the effects of reduced visual interference known as 'storage'. In the light of the well-established link between sleep and memory consolidation, our findings link the perceptual mechanisms of sensory adaptation--which are usually not considered to play a relevant role in mnemonic processes--with learning and memory, and at the same time reveal a new function of sleep in cognition.

  13. Institutionalization and Organizational Long-term Success

    Directory of Open Access Journals (Sweden)

    Denise L. Fleck

    2007-05-01

    Full Text Available Institutionalization processes have an ambivalent effect on organizational long-term success. Even though they foster organizational stability and permanence, they also bring about rigidity and resistance to change. As a result, successful organizations are likely to lose their competitive advantage over time. The paper addresses this issue through the investigation of the institutionalization processes of two long-lived companies: General Electric, a firm that has been a long-term success and its rival, Westinghouse, which was broken up after eleven decades of existence. The longitudinal, multilevel analysis of firms and industry has identified two different modes of organizational institutionalization. The reactive mode gives rise to rigidity and change resistance, much like institutional theory predicts; the proactive mode, on the other hand, neutralizes those negative effects of institutionalization processes. In the reactive mode, structure predominates. In the proactive mode, agency plays a major role in organizational institutionalization, and in managing the organization’s relations with the environment, clearly contributing to environmental institutionalization.

  14. Long-term manure amendment increases organic C storage and stabilization in Loess soil

    Science.gov (United States)

    Liang, B.; Zhao, W.; Yang, X.; Zhou, J.

    2011-12-01

    Soil is the largest terrestrial pool for organic carbon in the biosphere. Therefore, sequestration of C in soils is often seen as a 'win-win' proposition. The long-term combined application of manure with chemical fertilizers had increased the accumulation of organic carbon in soil (SOC); and the results from the application of chemical fertilizers on the stock of SOC in soil were inconsistent. Furthermore, less studies have been conducted to evaluate the effect of different fertilization, especially the application of N fertilizer, on the stabilization of SOC in the different fertilized soils. In this study, we hypothesized that the long-term different fertilization not only affect organic C storage, but also its stabilization in soil. Therefore, we conducted an incubation experiment with the soils from a long-term fertilization trials. Soil samples were collected from the three fertilized plots, ((1) no fertilizer, NF soil, (2) inorganic NPK fertilizers, NPK soil; and (3) Manure + NPK fertilizers, MNPK soil) of a long-term fertilization experiment initiated in 1990 in Shaanxi, China. The soils were incubated at 28o C for 30 days with the different treatments, i.e., (1) control with no addition (CK), (2) added 200 mg N kg-1 soil (+ NH4-N), (3) added 1000 mg C kg-1 soil (+ glucose), and (4) added 200 mg N kg-1 soil + 1000 mg C kg-1 soil (+glucose + NH4-N). The evolved CO2 was determined by titration of the excess NaOH with 0.1 M HCl. Decomposition of SOC in the different soils was evaluate with the accumulation of released CO2-C based on dry soil (in mg C kg-1 soil), and the decomposition rate of SOC during the incubation (in % of total organic C in soil). Long-term different fertilization treatments (NPK, and MNPK soil) significantly increased the organic C storage in 0-100 cm soil profile. SOC storage in MNPK soil (83.0 t ha-1) was significantly higher than NPK soil (80.8 t ha-1), and both were significantly higher than the no fertilizer soil. The decomposition

  15. Vajon in Translated Hungarian

    Directory of Open Access Journals (Sweden)

    Götz Andrea

    2016-12-01

    Full Text Available This paper presents an analysis of the structures the discourse marker vajon forms in translated Hungarian fiction. Although translation data has been deployed in the study of discourse markers (Aijmer & Simon- Vandenbergen, 2004, such studies do not account for translation-specific phenomena which can influence the data of their analysis. In addition, translated discourse markers could offer insights into the idiosyncratic properties of translated texts as well as the culturally defined norms of translation that guide the creation of target texts. The analysis presented in this paper extends the cross-linguistic approach beyond contrastive analysis with a detailed investigation of two corpora of translated texts in order to identify patterns which could be a sign of translation or genre norms impacting the target texts. As a result, a distinct, diverging pattern emerges between the two corpora: patterns of explicit polarity show a marked difference. However, further research is needed to clarify whether these are due to language, genre, or translation norms.

  16. 应用DNDC模型模拟关中地区农田长期施肥条件下土壤碳含量及作物产量%Simulation of Soil Carbon Contents and Crop Yields in Long-term Fertilized Cropland in Guanzhong Area Using DNDC Model

    Institute of Scientific and Technical Information of China (English)

    陈海心; 孙本华; 冯浩; 赵英; 张延

    2014-01-01

    Land use changes may have great impacts on dryland agriculture in the Loess Plateau of China, one of the most fragile agro-e-cosystems in the world. Here we investigated the variation of soil organic carbon(SOC)and crop yields in dryland under long-term different fertilization in Guanzhong plain area during 20 years using DNDC model. There were five treatments including no fertilization control(CK), inorganic fertilizers(NPK), NPK combined with straw(SNPK), NPK combined with low manure(M1NPK), and NPK combined with high manure(M2NPK). In the CK treatment, SOC and crop yields were significantly reduced. The NPK treatment promoted crop production, but had little effect on SOC, which was similar to that in CK. However, both SOC and crop yields were increased in the SNPK, M1NPK and M2NPK treatments, with the greatest effect observed in the M2NPK. These observed data were used to calibrate and verify DNDC model. The model showed good fitting to measured SOC and crop yields, and thus could be used to predict SOC and crop yields dynamics. The pre-diction by the model indicated that combination of inorganic fertilizers and manure could not only enhance crop aboveground and under-ground biomass and heterotrophic respiration, but also increase soil carbon storage. This result would shed light on fertilization practices in this region.%为探讨长期不同施肥条件下土壤有机碳和作物产量的变化规律及DNDC模型在关中地区的适用性,利用在陕西杨凌设置的长期定位施肥试验数据,选取不施肥(CK)、单施氮磷钾无机肥(NPK)、无机肥配施秸秆(SNPK)、无机肥配施低量有机肥(M1NPK)及无机肥配施高量有机肥(M2NPK)5个处理,分析了20年来土壤有机碳(SOC)含量、碳循环以及农作物产量的变化趋势等基本特征。分析数据表明:CK使得土壤肥力持续下降,显著地降低了SOC含量和作物产量;NPK处理虽可促进作物产量,但对表层土壤

  17. Inflectional marking in Hungarian aphasics.

    Science.gov (United States)

    MacWhinney, B; Osmán-Sági, J

    1991-08-01

    How do aphasics deal with the rich inflectional marking available in agglutinative languages like Hungarian? For the Hungarian noun alone, aphasics have to deal with over 15 basic case markings and dozens of possible combinations of these basic markings. Using the picture description task of MacWhinney and Bates (1978), this study examined the use of inflectional markings in nine Broca's and five Wernicke's aphasic speakers of Hungarian. The analysis focused on subject, direct object, indirect object, and locative nominal arguments. Compared to normals, both groups had a much higher rate of omission of all argument types. Subject ellipsis was particularly strong, as it is in normal Hungarian. There was a tendency for Broca's to omit the indirect object and for Wernicke's to omit the direct object. Across argument types, Wernicke's had a much higher level of pronoun usage than did Broca's. Broca's also showed a very high level of article omission. Compared to similar data reported by Slobin (this issue) for Turkish, the Hungarian aphasics showed an elevated level of omission of case markings. Addition errors were quite rare, but there were 14 substitutions of one case marking for another. These errors all involved the substitution of some close semantic competitor. There were no errors in the basic rules for vowel harmony or morpheme order. Overall the results paint a picture of a group of individuals whose grammatical abilities are damaged and noisy, but still largely functional. Neither the view of Broca's as agrammatic nor the view of Wernicke's as paragrammatic was strongly supported.

  18. Grassland biodiversity bounces back from long-term nitrogen addition.

    Science.gov (United States)

    Storkey, J; Macdonald, A J; Poulton, P R; Scott, T; Köhler, I H; Schnyder, H; Goulding, K W T; Crawley, M J

    2015-12-17

    The negative effect of increasing atmospheric nitrogen (N) pollution on grassland biodiversity is now incontrovertible. However, the recent introduction of cleaner technologies in the UK has led to reductions in the emissions of nitrogen oxides, with concomitant decreases in N deposition. The degree to which grassland biodiversity can be expected to 'bounce back' in response to these improvements in air quality is uncertain, with a suggestion that long-term chronic N addition may lead to an alternative low biodiversity state. Here we present evidence from the 160-year-old Park Grass Experiment at Rothamsted Research, UK, that shows a positive response of biodiversity to reducing N addition from either atmospheric pollution or fertilizers. The proportion of legumes, species richness and diversity increased across the experiment between 1991 and 2012 as both wet and dry N deposition declined. Plots that stopped receiving inorganic N fertilizer in 1989 recovered much of the diversity that had been lost, especially if limed. There was no evidence that chronic N addition has resulted in an alternative low biodiversity state on the Park Grass plots, except where there has been extreme acidification, although it is likely that the recovery of plant communities has been facilitated by the twice-yearly mowing and removal of biomass. This may also explain why a comparable response of plant communities to reduced N inputs has yet to be observed in the wider landscape.

  19. EFFECT OF LONG-TERM FERTILIZATION, STUBBLE MULCH AND IRRIGATION UNDER DIFFERENT FERTILIZATION ON SOIL ENZYME AND SOIL NUTRIENTS%长期施肥及不同施肥条件下秸秆覆盖、灌水对土壤酶和养分的影响

    Institute of Scientific and Technical Information of China (English)

    王改玲; 李立科; 郝明德; 洪坚平

    2012-01-01

    以陕西省合阳县的28年定位试验为依托,通过主成分分析和聚类分析,研究了施肥及不同施肥条件下秸秆覆盖、灌水对土壤脲酶、磷酸酶、转化酶、过氧化氢酶活性和土壤养分含量的影响。结果表明,NP肥施用对土壤脲酶无显著影响,而使磷酸酶、转化酶活性分别较对照提高119.6%和22.0%,NP有机肥(NPM肥)使脲酶、磷酸酶、转化酶活性分别较对照提高53.2%、130.8%和60.6%,NPM肥的作用大于NP肥;秸秆覆盖和灌水对脲酶、磷酸酶、转化酶活性的影响因施肥条件不同而表现不同;NP肥能提高土壤速效氮、速效磷和全氮含量,NP肥施用基础上灌水能提高土壤有机质、碱解氮和速效磷含量,NPM肥施量、NP肥及NPM肥施用基础上秸秆覆盖均能显著提高土壤有机质、碱解氮、速效磷、速效钾、全氮和全磷含量,其中速效磷的提高幅度最大,NPM肥较对照提高64.4mg/kg,NPM肥基础上秸秆覆盖使速效磷含量较施用NPM肥提高44.0mg/kg,施肥、秸秆覆盖和灌水对土壤全钾含量和过氧化氢酶活性影响总体上不显著。主成分分析和聚类分析表明,NPM肥和NPM肥结合灌水更有利于土壤养分和酶活性综合因子的提高,提高土壤肥力;秸秆覆盖有利于提高土壤养分,不利于酶活性综合因子的提高;灌水的影响较小。生产上应注意大量秸秆覆盖对土壤酶活性的不利影响。%On the basis of the 28-year experiment located in Heyang County, Shaanxi Province, effects of fertilization, stubble mulch and irrigation under different fertilization on soil urease, phosphatase, invertase, hydrogen peroxidase activities and contents of soil nutrients were studied through principal component analysis and cluster analysis. Results were as follows: the activities of Urease was not influenced by NP treatment, the activities of phosphatase and invertase increased 119.6% and 22.0% by NP treatment respectively. The

  20. [Femoral angioplasty. Long-term results].

    Science.gov (United States)

    Foucart, H; Carlier, C; Baudrillard, J C; Joffre, F; Cécile, J P

    1990-01-01

    A study on the long-term efficacy of femoral-popliteal angioplasty was carried out on 185 angioplasty cases over a 5 year follow-up period. A classification of data according to the type of lesion treated, revealed that results were favorable in case of stenosis (87%), short obstruction (70%) and long obstruction (35%). A special study of the outcome of treatments for stage IV arteritis was carried out. After comparing results with those obtained by other teams, the authors list the complications encountered, hematomas, and thromboses, and show their current tendency for regression. Lastly, the authors stress the advantages of angioscopy, which permits to identify the nature of the treated lesions and to predict possible complications, which are usually underrated by angiography.

  1. Technology for long-term care.

    Science.gov (United States)

    Tak, Sunghee H; Benefield, Lazelle E; Mahoney, Diane Feeney

    2010-01-01

    Severe staff shortages in long-term care (LTC) make it difficult to meet the demands of the growing aging population. Further, technology-savvy Baby Boomers are expected to reshape the current institutional environments toward gaining more freedom and control in their care and lives. Voices from business, academia, research, advocacy organizations, and government bodies suggest that innovative technological approaches are the linchpin that may prepare society to cope with these projected demands. In this article, we review the current state of aging-related technology, identify potential areas for efficacy testing on improving the quality of life of LTC residents in future research, and discuss barriers to implementation of LTC technology. Finally, we present a vision of future technology use that could transform current care practices.

  2. Emotional behavior in long-term marriage.

    Science.gov (United States)

    Carstensen, L L; Gottman, J M; Levenson, R W

    1995-03-01

    In exploring the emotional climate of long-term marriages, this study used an observational coding system to identify specific emotional behaviors expressed by middle-aged and older spouses during discussions of a marital problem. One hundred and fifty-six couples differing in age and marital satisfaction were studied. Emotional behaviors expressed by couples differed as a function of age, gender, and marital satisfaction. In older couples, the resolution of conflict was less emotionally negative and more affectionate than in middle-aged marriages. Differences between husbands and wives and between happy and unhappy marriages were also found. Wives were more affectively negative than husbands, whereas husbands were more defensive than wives, and unhappy marriages involved greater exchange of negative affect than happy marriages.

  3. Long-Term Stability of Horseshoe Orbits

    CERN Document Server

    Ćuk, Matija; Holman, Matthew J

    2012-01-01

    Unlike Trojans, horseshoe coorbitals are not generally considered to be long-term stable (Dermott and Murray, 1981; Murray and Dermott, 1999). As the lifetime of Earth's and Venus's horseshoe coorbitals is expected to be about a Gyr, we investigated the possible contribution of late-escaping inner planet coorbitals to the lunar Late Heavy Bombardment. Contrary to analytical estimates, we do not find many horseshoe objects escaping after first 100 Myr. In order to understand this behaviour, we ran a second set of simulations featuring idealized planets on circular orbits with a range of masses. We find that horseshoe coorbitals are generally long lived (and potentially stable) for systems with primary-to-secondary mass ratios larger than about 1200. This is consistent with results of Laughlin and Chambers (2002) for equal-mass pairs or coorbital planets and the instability of Jupiter's horseshoe companions (Stacey and Connors, 2008). Horseshoe orbits at smaller mass ratios are unstable because they must approa...

  4. [Enteral nutrition through long-term jejunostomy].

    Science.gov (United States)

    Fernández, T; Neira, P; Enríquez, C

    2008-01-01

    We present the case of a female patient suffering a peritonitis episode after subtotal gastrectomy due to gastric neoplasm in relation to lesser curvature necrosis extending to the anterior esophageal wall. This an uncommon andsevere complication that made mandatory further aggressive surgery: transection of the abdominal esophagus, transection of the gastric stump, and cervical esophagostomy with creation of a jejunostomy with a needle catheter for feeding. This digestive tube access technique is generally used during major abdominal post-surgery until oral intake is reestablished. Our patient has been 187 days with this therapy since reconstruction of the GI tract was ruled out due to tumoral infiltration of the colon and tumor recurrence at the gastrohepatic omentum. To date, there has been no complication from permanence and/or long-term use of this technique.

  5. Long-term variations of solar activity

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Using the Lomb-Scargle periodogram we analyzed two sunspot series: the one over the past 11000 years at the 10-year interval based upon the survey data of 14C concentration in tree-rings, reconstructed by Solanki et al.; and the sunspot number over the past 7000 years, derived from geomagnetic variations by Usoskin et al. We found the periods and quasi-periods in solar activity, such as about 225, 352, 441, 522 and 561 a, and near 1000 and 2000 a. An approach of wavelet transform was applied to check the two sunspot time series, with emphasis on investigating time-varying characteristics in the long-term fluctuations of solar activity. The results show that the lengths and amplitudes of the periods have changed with time, and large variations have taken place during some periods.

  6. Autobiographical reasoning in long-term fandom

    Directory of Open Access Journals (Sweden)

    C. Lee Harrington

    2010-09-01

    Full Text Available We explore the social psychological processes through which fan-based experiences become situated in fans' larger life narratives. Drawing on original survey data with long-term U.S. soap opera fans, we examine how the psychological mechanism of autobiographical reasoning functions in fans' construction of self-narratives over time. The case study presented here is a subset of a larger investigation into the age-related structure of fans' activities, identities, and interpretive capacities. Situated at the intersections of gerontological (life span/life course theory and contemporary fan studies, our project mines relatively uninvestigated theoretical terrain. We conclude with a brief discussion of implications for future fan studies.

  7. Brodie's abscess. A long-term review.

    Science.gov (United States)

    Stephens, M M; MacAuley, P

    1988-09-01

    In 20 patients with 21 Brodie's abscesses, a long-term review revealed that 13 occurred in the second decade of life. All had local symptoms for six weeks or more. The tibia was involved in 11 cases and seven of these were in the proximal metaphysis. The erythrocyte sedimentation rate (ESR) was elevated in only six cases. When the ESR was more than 40 mm per hour, recurrence was more likely. Staphylococcus aureus was cultured from 11 abscesses. Curettage and antibiotics for six weeks were adequate for treatment in most cases. However, lesions larger than 3 cm in diameter should be grafted, and patients with an elevated ESR require more aggressive decompression and prolonged antibiotic therapy. Lesions within the neck of the femur pose particular anatomic problems and should not be approached laterally. All cases were followed to full bone maturity. No significant leg length inequality was clinically or roentgenologically apparent. If an abscess was juxtaphyseal, deformity of the epiphysis could develop.

  8. Long-term dynamics of Typha populations

    Science.gov (United States)

    Grace, J.B.; Wetzel, R.G.

    1998-01-01

    The zonation of Typha populations in an experimental pond in Michigan was re-examined 15 years after the original sampling to gain insight into the long-term dynamics. Current distributions of Typha populations were also examined in additional experimental ponds at the site that have been maintained for 23 years. The zonation between T. latifolia and T. angustifolia in the previously studied pond 15 years after the initial sampling revealed that the density and distribution of shoots had not changed significantly. Thus, it appears that previously reported results (based on 7- year old populations) have remained consistent over time. Additional insight into the interaction between these two taxa was sought by comparing mixed and monoculture stands in five experimental ponds that have remained undisturbed for their 23-year history. The maximum depth of T. latifolia, the shallow- water species, was not significantly reduced when growing in the presence of the more flood tolerant T. angustifolia. In contrast, the minimum depth of T. angustifolia was reduced from 0 to 37 cm when in the presence of T. latifolia. When total populations were compared between monoculture and mixed stands, the average density of T. angustifolia shoots was 59.4 percent lower in mixed stands while the density of T. latifolia was 32 percent lower, with T. angustifolia most affected at shallow depths (reduced by 92 percent) and T. latifolia most affected at the deepest depths (reduced by 60 percent). These long-term observations indicate that competitive displacement between Typha taxa has remained stable over time.

  9. Long-term reductions in tinnitus severity

    Directory of Open Access Journals (Sweden)

    Folmer Robert L

    2002-09-01

    Full Text Available Abstract Background This study was undertaken to assess long-term changes in tinnitus severity exhibited by patients who completed a comprehensive tinnitus management program; to identify factors that contributed to changes in tinnitus severity within this population; to contribute to the development and refinement of effective assessment and management procedures for tinnitus. Methods Detailed questionnaires were mailed to 300 consecutive patients prior to their initial appointment at the Oregon Health & Science University Tinnitus Clinic. All patients were then evaluated and treated within a comprehensive tinnitus management program. Follow-up questionnaires were mailed to the same 300 patients 6 to 36 months after their initial tinnitus clinic appointment. Results One hundred ninety patients (133 males, 57 females; mean age 57 years returned follow-up questionnaires 6 to 36 months (mean = 22 months after their initial tinnitus clinic appointment. This group of patients exhibited significant long-term reductions in self-rated tinnitus loudness, Tinnitus Severity Index scores, tinnitus-related anxiety and prevalence of current depression. Patients who improved their sleep patterns or Beck Depression Inventory scores exhibited greater reductions of tinnitus severity scores than patients who continued to experience insomnia and depression at follow-up. Conclusions Individualized tinnitus management programs that were designed for each patient contributed to overall reductions in tinnitus severity exhibited on follow-up questionnaires. Identification and treatment of patients experiencing anxiety, insomnia or depression are vital components of an effective tinnitus management program. Utilization of acoustic therapy also contributed to improvements exhibited by these patients.

  10. Long term results of pneumatic retinopexy

    Directory of Open Access Journals (Sweden)

    Ellakwa AF

    2012-01-01

    Full Text Available Amin F EllakwaMenoufiya University, Shibin el Kom, Al-Menoufiya, EgyptBackground: Rhegmatogenous retinal detachment is a commonly encountered retinal problem where rapid treatment can prevent irreversible vision loss. Pneumatic retinopexy (PR is a simple, minimally invasive procedure for retinal reattachment.Purpose: This study aimed to assess the long-term anatomical and functional outcome of pneumatic retinopexy in primary rhegmatogenous retinal detachment.Patients and methods: A prospective interventional study was performed. Subjects with rhegmatogenous retinal detachment who underwent pneumatic retinopexy from May 2006 to May 2007 at Menoufiya University Hospital were included in this study with at least 3 years follow-up.Results: A total of 40 cases were included in the study. The mean age of patients was 44.25 ± 10.85 years. Reattachment of the retina was achieved in 100% of cases. In 75% of cases, the primary intervention was successful. However, the retina redetached in 20% of these during the first 6 months, requiring reinjection or another procedure. Three years after the first intervention, follow-up measurement of the mean visual acuity of the eyes without reoperation was 0.40 ± 0.21 while the mean visual acuity of the eyes which needed additional operations was 0.22 ± 0.13.Conclusion: Sixty percent of the cases obtained long-term retinal reattachment with a single operation success (SOS, with good visual recovery and less morbidity than other more invasive procedures like scleral buckling or pars plana vitrectomy, translating to higher productivity for the patient. This procedure, being quicker than the alternatives, also saves the surgeon's time, making PR a good choice for managing primary rhegmatogenous retinal detachment in developing countries.Keywords: pneumatic, retinopexy, rhegmatogenous, retinal detachment

  11. Long-term potentiation and long-term depression: a clinical perspective

    Directory of Open Access Journals (Sweden)

    Timothy V.P. Bliss

    2011-01-01

    Full Text Available Long-term potentiation and long-term depression are enduring changes in synaptic strength, induced by specific patterns of synaptic activity, that have received much attention as cellular models of information storage in the central nervous system. Work in a number of brain regions, from the spinal cord to the cerebral cortex, and in many animal species, ranging from invertebrates to humans, has demonstrated a reliable capacity for chemical synapses to undergo lasting changes in efficacy in response to a variety of induction protocols. In addition to their physiological relevance, long-term potentiation and depression may have important clinical applications. A growing insight into the molecular mechanisms underlying these processes, and technological advances in non-invasive manipulation of brain activity, now puts us at the threshold of harnessing long-term potentiation and depression and other forms of synaptic, cellular and circuit plasticity to manipulate synaptic strength in the human nervous system. Drugs may be used to erase or treat pathological synaptic states and non-invasive stimulation devices may be used to artificially induce synaptic plasticity to ameliorate conditions arising from disrupted synaptic drive. These approaches hold promise for the treatment of a variety of neurological conditions, including neuropathic pain, epilepsy, depression, amblyopia, tinnitus and stroke.

  12. Elevated rheumatoid factor and long term risk of rheumatoid arthritis

    DEFF Research Database (Denmark)

    Nielsen, Sune F; Bojesen, Stig E; Schnohr, Peter;

    2012-01-01

    To test whether elevated concentration of rheumatoid factor is associated with long term development of rheumatoid arthritis.......To test whether elevated concentration of rheumatoid factor is associated with long term development of rheumatoid arthritis....

  13. Long term hypolipidaemic and anti-atherogenic effects of Carica ...

    African Journals Online (AJOL)

    Long term hypolipidaemic and anti-atherogenic effects of Carica papaya Linn. ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... This study was designed to assess the long term (24 weeks) effects of daily oral ...

  14. Seasonal And Long Term Rainfall Trends In Calabar, Nigeria ...

    African Journals Online (AJOL)

    Seasonal And Long Term Rainfall Trends In Calabar, Nigeria. ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search ... Both seasonal and long term trends of rain fall in Calabar between 1985 and 2003 have been examined.

  15. Memory Vocabulary Learning Strategies and Long-Term Retention ...

    African Journals Online (AJOL)

    Memory Vocabulary Learning Strategies and Long-Term Retention. ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING ... The results were reflected in the students' short-term and long-term memory retention.

  16. IPO-related organizational change and long-term performance

    NARCIS (Netherlands)

    Eije, J.H. von; Witte, M.C. de; Zwaan, A.H. van der

    2000-01-01

    Mainstream literature on long-term performance of initial public offerings focuses on long-term underperformance. Because underperformance is an anomalous phenomenon, many authors search for explanations based on financial market imperfections. More recently, however, the attention shifts from

  17. LONG-TERM MONITORING SENSOR NETWORK

    Energy Technology Data Exchange (ETDEWEB)

    Stephen P. Farrington; John W. Haas; Neal Van Wyck

    2003-10-16

    Long-term monitoring (LTM) associated with subsurface contamination sites is a key element of Long Term Stewardship and Legacy Management across the Department of Energy (DOE) complex. However, both within the DOE and elsewhere, LTM is an expensive endeavor, often exceeding the costs of the remediation phase of a clean-up project. The primary contributors to LTM costs are associated with labor. Sample collection, storage, preparation, analysis, and reporting can add a significant financial burden to project expense when extended over many years. Development of unattended, in situ monitoring networks capable of providing quantitative data satisfactory to regulatory concerns has the potential to significantly reduce LTM costs. But survival and dependable operation in a difficult environment is a common obstacle to widespread use across the DOE complex or elsewhere. Deploying almost any sensor in the subsurface for extended periods of time will expose it to chemical and microbial degradation. Over the time-scales required for in situ LTM, even the most advanced sensor systems may be rendered useless. Frequent replacement or servicing (cleaning) of sensors is expensive and labor intensive, offsetting most, if not all, of the cost savings realized with unattended, in situ sensors. To enable facile, remote monitoring of contaminants and other subsurface parameters over prolonged periods, Applied Research Associates, Inc has been working to develop an advanced LTM sensor network consisting of three key elements: (1) an anti-fouling sensor chamber that can accommodate a variety of chemical and physical measurement devices based on electrochemical, optical and other techniques; (2) two rapid, cost effective, and gentle means of emplacing sensor packages either at precise locations directly in the subsurface or in pre-existing monitoring wells; and (3) a web browser-based data acquisition and control system (WebDACS) utilizing field-networked microprocessor-controlled smart

  18. Canopy spectral characteristics of crops and prediction on main nutrients uptake in long-term fertilization experiment%长期定位施肥条件下作物光谱特征及养分吸收量预测

    Institute of Scientific and Technical Information of China (English)

    张俊华; 张佳宝

    2014-01-01

    为了明确不同施肥条件下典型生育期冬小麦和夏玉米冠层光谱特征差异,该研究以长期定位施肥试验为研究对象,在确定典型生育期作物冠层光谱反射率与收获期作物地上部分主要养分吸收量相关性的基础上,建立收获期作物主要养分吸收量预测模型。结果表明,可见光波段相似生育期夏玉米冠层光谱反射率与冬小麦相近,但在近红外区域平均高于冬小麦8.42%。生育中期2种作物秸秆、籽粒及地上部分氮(N)、磷(P)、钾(K)吸收量与冠层光谱反射率在可见光波段普遍呈极显著负相关关系,在近红外波段呈极显著正相关关系。全生育期夏玉米冠层光谱反射率与作物吸氮量的相关系数在可见光波段基本持平,但在近红外波段平均高于冬小麦0.4152。全生育期夏玉米冠层反射率与地上部分吸磷量的相关系数在可见光波段和近红外区域较冬小麦平均分别低0.3621和0.2072。全生育期夏玉米冠层光谱反射率与地上部分吸钾量相关系数在可见光波段平均低于冬小麦0.1270,在近红外波段高于冬小麦0.0341。除夏玉米吸磷量外,基于冬小麦和夏玉米典型生育期冠层光谱反射率建立的模型均可准确预测收获期作物主要养分吸收量,且对冬小麦养分吸收量的预测精度略高于夏玉米,该结论可以为黄淮海地区冬小麦和夏玉米的长势监测和肥料管理提供科学依据。%Nitrogen (N), phosphorus (P) and potassium (K) are the necessary nutrients for the plant growth. To save the cost and minimize ecological impact of fertilizer application, it is important to use variable rate of fertilizer management to address differences in plant nutrients requirements. The objective of this study was to develop a model to predict winter wheat and maize N, P, and K uptake based on canopy spectral reflectance from a long-term fertilizer experiment in Huang

  19. Long-term outcome of neuroparacoccidioidomycosis treatment

    Directory of Open Access Journals (Sweden)

    Fabio Francesconi

    2011-02-01

    Full Text Available INTRODUCTION: Neuroparacoccidioidomycosis (NPCM is a term used to describe the invasion of the central nervous system by the pathogenic fungus Paracoccidioides brasiliensis. NPCM has been described sporadically in some case reports and small case series, with little or no focus on treatment outcome and long-term follow-up. METHODS: All patients with NPCM from January 1991 to December 2006 were analyzed and were followed until December 2009. RESULTS: Fourteen (3.8% cases of NPCM were identified out of 367 patients with paracoccidioidomycosis (PCM. A combination of oral fluconazole and sulfamethoxazole/trimethoprim (SMZ/TMP was the regimen of choice, with no documented death due to Paracoccidioides brasiliensis infection. Residual neurological deficits were observed in 8 patients. Residual calcification was a common finding in neuroimaging follow-up. CONCLUSIONS: All the patients in this study responded positively to the association of oral fluconazole and sulfamethoxazole/trimethoprim, a regimen that should be considered a treatment option in cases of NPCM. Neurological sequela was a relatively common finding. For proper management of these patients, anticonvulsant treatment and physical therapy support were also needed.

  20. Long-Term Soft Denture Lining Materials

    Science.gov (United States)

    Chladek, Grzegorz; Żmudzki, Jarosław; Kasperski, Jacek

    2014-01-01

    Long-term soft denture lining (LTSDL) materials are used to alleviate the trauma associated with wearing complete dentures. Despite their established clinical efficacy, the use of LTSDLs has been limited due to the unfavorable effects of the oral environment on some of their mechanical and performance characteristics. The unresolved issue of LTSDL colonization by Candida albicans is particularly problematic. Silicone-based LTSDL (SLTSDL) materials, which are characterized by more stable hardness, sorption and solubility than acrylic-based LTSDLs (ALTSDLs), are currently the most commonly used LTSDLs. However, SLTSDLs are more prone to debonding from the denture base. Moreover, due to their limitations, the available methods for determining bond strength do not fully reflect the actual stability of these materials under clinical conditions. SLTSDL materials exhibit favorable viscoelastic properties compared with ALTSDLs. Furthermore, all of the lining materials exhibit an aging solution-specific tendency toward discoloration, and the available cleansers are not fully effective and can alter the mechanical properties of LTSDLs. Future studies are needed to improve the microbiological resistance of LTSDLs, as well as some of their performance characteristics. PMID:28788163

  1. Long-term predictions using natural analogues

    Energy Technology Data Exchange (ETDEWEB)

    Ewing, R.C. [Univ. of New Mexico, Albuquerque, NM (United States)

    1995-09-01

    One of the unique and scientifically most challenging aspects of nuclear waste isolation is the extrapolation of short-term laboratory data (hours to years) to the long time periods (10{sup 3}-10{sup 5} years) required by regulatory agencies for performance assessment. The direct validation of these extrapolations is not possible, but methods must be developed to demonstrate compliance with government regulations and to satisfy the lay public that there is a demonstrable and reasonable basis for accepting the long-term extrapolations. Natural systems (e.g., {open_quotes}natural analogues{close_quotes}) provide perhaps the only means of partial {open_quotes}validation,{close_quotes} as well as data that may be used directly in the models that are used in the extrapolation. Natural systems provide data on very large spatial (nm to km) and temporal (10{sup 3}-10{sup 8} years) scales and in highly complex terranes in which unknown synergisms may affect radionuclide migration. This paper reviews the application (and most importantly, the limitations) of data from natural analogue systems to the {open_quotes}validation{close_quotes} of performance assessments.

  2. Long-term corrosion testing pan.

    Energy Technology Data Exchange (ETDEWEB)

    Wall, Frederick Douglas; Brown, Neil R. (Los Alamos National Laboratory, Los Alamos, NM)

    2008-08-01

    This document describes the testing and facility requirements to support the Yucca Mountain Project long-term corrosion testing needs. The purpose of this document is to describe a corrosion testing program that will (a) reduce model uncertainty and variability, (b) reduce the reliance upon overly conservative assumptions, and (c) improve model defensibility. Test matrices were developed for 17 topical areas (tasks): each matrix corresponds to a specific test activity that is a subset of the total work performed in a task. A future document will identify which of these activities are considered to be performance confirmation activities. Detailed matrices are provided for FY08, FY09 and FY10 and rough order estimates are provided for FY11-17. Criteria for the selection of appropriate test facilities were developed through a meeting of Lead Lab and DOE personnel on October 16-17, 2007. These criteria were applied to the testing activities and recommendations were made for the facility types appropriate to carry out each activity. The facility requirements for each activity were assessed and activities were identified that can not be performed with currently available facilities. Based on this assessment, a total of approximately 10,000 square feet of facility space is recommended to meet all future testing needs, given that all testing is consolidated to a single location. This report is a revision to SAND2007-7027 to address DOE comments and add a series of tests to address NWTRB recommendations.

  3. Long-term corrosion testing plan.

    Energy Technology Data Exchange (ETDEWEB)

    Wall, Frederick Douglas; Brown, Neil R. (Los Alamos National Laboratory, Los Alamos, NM)

    2009-02-01

    This document describes the testing and facility requirements to support the Yucca Mountain Project long-term corrosion testing program. The purpose of this document is to describe a corrosion testing program that will (a) reduce model uncertainty and variability, (b) reduce the reliance upon overly conservative assumptions, and (c) improve model defensibility. Test matrices were developed for 17 topical areas (tasks): each matrix corresponds to a specific test activity that is a subset of the total work performed in a task. A future document will identify which of these activities are considered to be performance confirmation activities. Detailed matrices are provided for FY08, FY09 and FY10 and rough order estimates are provided for FY11-17. Criteria for the selection of appropriate test facilities were developed through a meeting of Lead Lab and DOE personnel on October 16-17, 2007. These criteria were applied to the testing activities and recommendations were made for the facility types appropriate to carry out each activity. The facility requirements for each activity were assessed and activities were identified that can not be performed with currently available facilities. Based on this assessment, a total of approximately 10,000 square feet of facility space is recommended to accommodate all future testing, given that all testing is consolidated to a single location. This report is a revision to SAND2008-4922 to address DOE comments.

  4. Downlink Scheduling in Long Term Evolution

    Directory of Open Access Journals (Sweden)

    Anwar Hossain

    2015-06-01

    Full Text Available This is an investigated research article on resource block scheduling of Long Term Evolution (LTE. LTE is one of the evolutions of the Universal Mobile Telecommunication System (UMTS. It provides internet access to mobile users through smart phone, laptop and other android devices. LTE offers a high speed data and multimedia services. It supports data rates up to 100 Mbps in the downlink and 50 Mbps in the uplink transmission. Our research investigation was aim to the downlink scheduling. We have considered The Best CQI scheduling algorithm and the Round Robin scheduling algorithm. The implementation, analysis and comparison of these scheduling algorithms have been performed through MATLAB simulator. We have analyzed the impact of the scheduling schemes on the throughput and the fairness of both scheduling schemes. Here we have proposed a new scheduling algorithm that achieves a compromise between the throughput and the fairness. Orthogonal Frequency Division Multiplexing (OFDM has been adopted as the downlink transmission scheme. We have considered the impact of the channel delay on the throughput. In addition, MIMO transceiver systems have been implemented to increase the throughput

  5. Long Term Evolution of Plasma Wakefields

    CERN Document Server

    Sahai, Aakash A; Tsung, F S; Mori, W B

    2014-01-01

    We study the long-term evolution (LTE) of plasma wakefields over multiple plasma-electron periods and few plasma-ion periods, much less than a recombination time. The evolution and relaxation of such a wakefield-perturbed plasma over these timescales has important implications for the upper limits of repetition-rates in plasma colliders. Intense fields in relativistic lasers (or intense beams) create plasma wakefields (modes around {\\omega}pe) by transferring energy to the plasma electrons. Charged-particle beams in the right phase may be accelerated with acceleration/focusing gradients of tens of GeV/m. However, wakefields leave behind a plasma not in equilibrium, with a relaxation time of multiple plasma-electron periods. Ion motion over ion timescales, caused by energy transfer from the driven plasma-electrons to the plasma-ions can create interesting plasma states. Eventually during LTE, the dynamics of plasma de-coheres (multiple modes through instability driven mixing), thermalizing into random motion (...

  6. Long term results of mandibular distraction

    Directory of Open Access Journals (Sweden)

    Batra Puneet

    2006-03-01

    Full Text Available Mandibular distraction osteogenesis has become a popular surgical modality due to its many advantages over conventional orthognathic surgical procedures. However, in spite of the technique having been used for over 15 years, no concrete long term results are available regarding the stability of results. We discuss the various studies which have reported either in favour or against the stablility of results after distraction. We report a series of 6 cases (3 unilateral and 3 bilateral distraction where distraction was carried out before puberty and followed them up to seven years after removal of distractors. This case series shows that results achieved by distraction osteogenesis are unstable or best unpredictable with respect to producing a permanent size increase in the mandible. The role of the distraction osteogenesis in overcoming the pterygomassetric sling is questionable. We suggest a multicenter study with adequate patient numbers treated with a similar protocol and documented after growth cessation to have meaningful conclusions on the debate of distraction osteogenesis versus orthognathic surgery.

  7. Long-term data storage in diamond

    Science.gov (United States)

    Dhomkar, Siddharth; Henshaw, Jacob; Jayakumar, Harishankar; Meriles, Carlos A.

    2016-01-01

    The negatively charged nitrogen vacancy (NV−) center in diamond is the focus of widespread attention for applications ranging from quantum information processing to nanoscale metrology. Although most work so far has focused on the NV− optical and spin properties, control of the charge state promises complementary opportunities. One intriguing possibility is the long-term storage of information, a notion we hereby introduce using NV-rich, type 1b diamond. As a proof of principle, we use multicolor optical microscopy to read, write, and reset arbitrary data sets with two-dimensional (2D) binary bit density comparable to present digital-video-disk (DVD) technology. Leveraging on the singular dynamics of NV− ionization, we encode information on different planes of the diamond crystal with no cross-talk, hence extending the storage capacity to three dimensions. Furthermore, we correlate the center’s charge state and the nuclear spin polarization of the nitrogen host and show that the latter is robust to a cycle of NV− ionization and recharge. In combination with super-resolution microscopy techniques, these observations provide a route toward subdiffraction NV charge control, a regime where the storage capacity could exceed present technologies.

  8. DIFFERENTIAL DIAGNOSIS OF LONG TERM TONGUE ULCERS

    Directory of Open Access Journals (Sweden)

    Hegde Nidarsh D.

    2012-08-01

    Full Text Available Oral ulcers is a very common disorder of the oral mucosa. Patients with signs or symptoms of oral ulcers are sometimes referred to gastroenterology clinics, however, in most instances the ulcers does not reflect gastrointestinal disease, some with a chronic non- healing ulcer are advised biopsy. Indeed, a spectrum of disorders can give rise to oral mucosal ulcers ranging from minor local trauma to significant local disease such as malignancy or systemic illness. Lesions of the tongue have a broad differential diagnosis ranging from benign idiopathic processes to infections, cancers, and infiltrative disorders. This article will focus on common ulcerative disorders of the tongue in aspects of their clinical features and differential diagnosis, two case reports with the diagnosis and conservative management for long-term chronic ulcers. The two cases which are reported in this article had a differential diagnosis of Squamous cell carcinoma of the tongue. The clinical picture was craterlike lesion, having a velvety-red base and a rolled, indurated border and most important painless in both cases. Removal of the irritant which was the tooth, rehabilitation of the oral mucosa by lubrication with Cocus Nucifera resulted in the healing of the ulcers. Functional components of Cocus Nucifera are Squaline, tocopherol, phytosterols and other sterols which are all plant steroids.

  9. Long-Term Soft Denture Lining Materials

    Directory of Open Access Journals (Sweden)

    Grzegorz Chladek

    2014-08-01

    Full Text Available Long-term soft denture lining (LTSDL materials are used to alleviate the trauma associated with wearing complete dentures. Despite their established clinical efficacy, the use of LTSDLs has been limited due to the unfavorable effects of the oral environment on some of their mechanical and performance characteristics. The unresolved issue of LTSDL colonization by Candida albicans is particularly problematic. Silicone-based LTSDL (SLTSDL materials, which are characterized by more stable hardness, sorption and solubility than acrylic-based LTSDLs (ALTSDLs, are currently the most commonly used LTSDLs. However, SLTSDLs are more prone to debonding from the denture base. Moreover, due to their limitations, the available methods for determining bond strength do not fully reflect the actual stability of these materials under clinical conditions. SLTSDL materials exhibit favorable viscoelastic properties compared with ALTSDLs. Furthermore, all of the lining materials exhibit an aging solution-specific tendency toward discoloration, and the available cleansers are not fully effective and can alter the mechanical properties of LTSDLs. Future studies are needed to improve the microbiological resistance of LTSDLs, as well as some of their performance characteristics.

  10. CERN Services for Long Term Data Preservation

    CERN Document Server

    Shiers, Jamie; Blomer, Jakob; Ganis, Gerardo; Dallmeier-Tiessen, Sunje; Simko, Tibor; Cancio Melia, German; CERN. Geneva. IT Department

    2016-01-01

    In this paper we describe the services that are offered by CERN for Long Term preservation of High Energy Physics (HEP) data, with the Large Hadron Collider (LHC) as a key use case. Data preservation is a strategic goal for European High Energy Physics (HEP), as well as for the HEP community worldwide and we position our work in this global content. Specifically, we target the preservation of the scientific data, together with the software, documentation and computing environment needed to process, (re-)analyse or otherwise (re-)use the data. The target data volumes range from hundreds of petabytes (PB – 10^15 bytes) to hundreds of exabytes (EB – 10^18 bytes) for a target duration of several decades. The Use Cases driving data preservation are presented together with metrics that allow us to measure how close we are to meeting our goals, including the possibility for formal certification for at least part of this work. Almost all of the services that we describe are fully generic – the exception being A...

  11. 40 CFR 52.29 - Visibility long-term strategies.

    Science.gov (United States)

    2010-07-01

    ...-term strategy. (1) A long-term strategy is a 10- to 15-year plan for making reasonable progress toward... every 3 years from November 24, 1987. (3) During the long-term strategy review process, the... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Visibility long-term strategies. 52.29...

  12. TIA and Stroke: the long-term perspective

    NARCIS (Netherlands)

    Wijk, I. van

    2006-01-01

    Background Survival after stroke has improved, but little is known about the long-term risk of new vascular events and the functioning of long-term survivors. The main objective of this thesis was to evaluate the long-term perspective of these patients. Methods Two longitudinal studies were carried

  13. CHARACTERISTICS OF LONG-TERM UNEMPLOYMENT SPELLS IN ROMANIA

    OpenAIRE

    Daniela-Emanuela Danacica; Raluca Mazilescu

    2012-01-01

    The aim of this paper is to analyze characteristics of long-term unemployment spells in Romania and to estimate the effect of factors influencing long-term unemployment spells. The study period is in between January 1st 2008 and December 31st 2010. 468159 long-term spells registered in the specified period at the National Agency of Employment are analyzed.

  14. Multiple Operator Movements in Hungarian

    NARCIS (Netherlands)

    Surányi, L.B.

    2003-01-01

    In this thesis I argue for an approach to multiple operator constructions in Hungarian within a radically derivational model which heavily restricts the role of pre-fabricated functional A-bar projections and which holds that it is the verb in this language that carries and projects the relevant ope

  15. Scientific Understanding from Long Term Observations: Insights from the Long Term Ecological Research (LTER) Program

    Science.gov (United States)

    Gosz, J.

    2001-12-01

    The network dedicated to Long Term Ecological Research (LTER) in the United States has grown to 24 sites since it was formed in 1980. Long-term research and monitoring are performed on parameters thatare basic to all ecosystems and are required to understand patterns, processes, and relationship to change. Collectively, the sites in the LTER Network provide opportunities to contrast marine, coastal, and continental regions, the full range of climatic gradients existing in North America, and aquatic and terrestrial habitats in a range of ecosystem types. The combination of common core areas and long-term research and monitoring in many habitats have allowed unprecedented abilities to understand and compare complex temporal and spatial dynamics associated with issues like climate change, effects of pollution, biodiversity and landuse. For example, McMurdo Dry Valley in the Antarctic has demonstrated an increase in glacier mass since 1993 which coincides with a period of cooler than normal summers and more than average snowfall. In contrast, the Bonanza Creek and Toolik Lake sites in Alaska have recorded a warming period unprecedented in the past 200 years. Nitrogen deposition effects have been identified through long-term watershed studies on biogeochemical cycles, especially at Coweeta Hydrological Lab, Harvard Forest, and the Hubbard Brook Experimental Forest. In aquatic systems, such as the Northern Temperate Lakes site, long-term data revealed time lags in effects of invaders and disturbance on lake communities. Biological recovery from an effect such as lake acidification was shown to lag behind chemical recovery. The long-term changes documented over 2 decades have been instrumental in influencing management practices in many of the LTER areas. In Puerto Rico, the Luquillo LTER demonstrated that dams obstruct migrations of fish and freshwater shrimp and water abstraction at low flows can completely obliterate downstream migration of juveniles and damage

  16. Modeling Maintenance of Long-Term Potentiation in Clustered Synapses: Long-Term Memory without Bistability

    Directory of Open Access Journals (Sweden)

    Paul Smolen

    2015-01-01

    Full Text Available Memories are stored, at least partly, as patterns of strong synapses. Given molecular turnover, how can synapses maintain strong for the years that memories can persist? Some models postulate that biochemical bistability maintains strong synapses. However, bistability should give a bimodal distribution of synaptic strength or weight, whereas current data show unimodal distributions for weights and for a correlated variable, dendritic spine volume. Thus it is important for models to simulate both unimodal distributions and long-term memory persistence. Here a model is developed that connects ongoing, competing processes of synaptic growth and weakening to stochastic processes of receptor insertion and removal in dendritic spines. The model simulates long-term (>1 yr persistence of groups of strong synapses. A unimodal weight distribution results. For stability of this distribution it proved essential to incorporate resource competition between synapses organized into small clusters. With competition, these clusters are stable for years. These simulations concur with recent data to support the “clustered plasticity hypothesis” which suggests clusters, rather than single synaptic contacts, may be a fundamental unit for storage of long-term memory. The model makes empirical predictions and may provide a framework to investigate mechanisms maintaining the balance between synaptic plasticity and stability of memory.

  17. Nutritional deficit and Long Term Potentiation alterations

    Directory of Open Access Journals (Sweden)

    M. Petrosino

    2009-01-01

    Full Text Available In the present work we examined the ability of prenatally malnourished offspring to produce and maintain long-term potentiation (LTP of the perforant path/dentate granule cell synapse in freely moving rats at 15,30, and 90 days of age. Population spike amplitude (PSA was calculated from dentate field potential recordings prior to and at 15, 30, 60 min. and 3, 5, 18 and 24 h following tetanization of the perforant pathway. All animals of both malnourished and well-nourished diet groups at 15 days of age showed potentiation of PSA measures but the measures obtained from 15-day-old prenatally malnourished animals were significantly less than that of age-matched, well-nourished controls. At 30 days of age, remarkable effect of tetanization was likely observed from PSA measures for this age group followed much the same pattern. At 90 days of age, PSA measures obtained from malnourished animals decreased from pretetanization levels immediately following tetanization. At this age, however, at three hours time recordings, this measure growing up to a level which did not differ significantly from that of the control group. These results indicate that the width of tetanization induced enhancement of dentate granule cell response in preweanling rats (15-day-old animals is signifacantly affected fromgestational protein malnutrition and this trend is kept in animals tested at 30 and 90 days of age. The fact, however, that considerable limitation in LTP generation was gained from prenatally malnourished animals at 90 days of age, implying that dietary rehabilitation starting at birth is an intervention strategy not capable to imbrove the effects of the gestational stress.

  18. A new long-term care manifesto.

    Science.gov (United States)

    Kane, Robert L

    2015-04-01

    This article argues for a fresh look at how we provide long-term care (LTC) for older persons. Essentially, LTC offers a compensatory service that responds to frailty. Policy debate around LTC centers on costs, but we are paying for something we really don't want. Building societal enthusiasm (or even support) for LTC will require re-inventing and re-branding. LTC has three basic components: personal care, housing, and health care (primarily chronic disease management). They can be delivered in a variety of settings. It is rare to find all three done well simultaneously. Personal care (PC) needs to be both competent and compassionate. Housing must provide at least minimal amenities and foster autonomy; when travel time for PC raises costs dramatically, some form of clustered housing may be needed. Health care must be proactive, aimed at preventing exacerbations of chronic disease and resultant hospitalizations. Enhancing preferences means allowing taking informed risks. Payment incentives should reward both quality of care and quality of life, but positive outcomes must be defined as slowing decline. Paying for services but not for housing under Medicaid would automatically level the playing field between nursing homes (NH) and community-based services. Regulations should achieve greater parity between NH and community care and include both positive and negative feedback. Providing post-acute care should be separate from LTC. Using the tripartite LTC framework, we can create innovative flexible approaches to providing needed services for frail older persons in formats that are both desirable and affordable. Such care will be more socially desirable and hence worth paying for.

  19. Long term cultivation of larger benthic Foraminifera

    Science.gov (United States)

    Wöger, Julia; Eder, Wolfgang; Kinoshita, Shunichi; Antonino, Briguglio; Carles, Ferrandes-Cañadell; Hohenegger, Johann

    2015-04-01

    Benthic Foraminifera are used in a variety of applications employing numerous different methods, i.e. ecological monitoring, studying the effects of ocean acidification, reconstructing palaeo-bathymetry or investigating palaeo-salinity and palaeo-temperature to name only a few. To refine our understanding of ecological influences on larger benthic foraminiferal biology and to review inferences from field observations, culture experiments have become an indispensable tool. While culture experiments on smaller benthic foraminifera have become increasingly frequent in the past century, reports of the cultivation of symbiont bearing larger Foraminifera are rare. Generally, cultivation experiments can be divided into two groups: Culturing of populations and cultivation of single specimens allowing individual investigation. The latter differ form the former by several restrictions resulting from the need to limit individual motility without abridging microenvironmental conditions in the Foraminiferans artificial habitat, necessary to enable the individual to development as unfettered as possible. In this study we present first experiences and preliminary results of the long-term cultivation of larger benthic Foraminifera conducted at the 'Tropical Biosphere Research Station Sesoko Island, University of the Ryukyus', Japan, trying to reproduce natural conditions as closely as possible. Individuals of three species of larger benthic Foraminifera (Heterostegina depressa, Palaeonummulites venosus and Operculina complanata) have been cultured since April 2014. At the time of the general assembly the cultivation experiments will have been going on for more than one year, with the aim to investigate growth rates, longevities and reproduction strategies for comparison with results statistically inferred from application of the of the 'natural laboratory' method. The most important factor influencing foraminiferal health and development was found to be light intensity and light

  20. Hormonal changes during long-term isolation.

    Science.gov (United States)

    Custaud, M A; Belin de Chantemele, E; Larina, I M; Nichiporuk, I A; Grigoriev, A; Duvareille, M; Gharib, C; Gauquelin-Koch, G

    2004-05-01

    Confinement and inactivity induce considerable psychological and physiological modifications through social and sensory deprivation. The aim of the SFINCSS-99 experiment was to determine the cardiovascular and hormonal pattern of blood volume regulation during long-term isolation and confinement. Simulation experiments were performed in pressurized chambers similar in size to the volumes of modern space vehicles. Group I consisted of four Russian male volunteers, who spent 240 days in a 100-m(3 )chamber. Group II included four males (one German and three Russians) who spent 110 days in isolation (200-m(3) module). The blood samples, taken before, during and after the isolation period, were used to determine haematocrit (Ht), growth hormone (GH), active renin, aldosterone, and osmolality levels. From the urine samples, electrolytes, osmolality, nitrites, nitrates, cortisol, antidiuretic hormone (ADH), aldosterone, normetanephrine and metanephrine levels were determined. The increase in plasma volume (PV) that is associated with a tendency for a decrease in plasma active renin is likely to be due to decreased sympathetic activity, and concords with the changes in urinary catecholamine levels during confinement. Urinary catecholamine levels were significantly higher during the recovery period than during confinement. This suggests that the sympathoadrenal system was activated, and concords with the increase in heart rate. Vascular resistance is determined by not only the vasoconstrictor but also vasodilator systems. The ratio of nitrite/nitrate in urine, as an indicator of nitric oxide release, did not reveal any significant changes. Analysis of data suggests that the duration of the isolation was a main factor involved in the regulation of hormones.