scholarly journals effect of crop rotation and fertilization on wheat and maize in the pedoclimatic conditions of the Banat Plain

2010 ◽  
pp. 14-18
Author(s):  
Iacob Borza ◽  
Ludovic Cseke-Kreppel ◽  
Cosmin Dragos ◽  
Ioan Gaica ◽  
Mădălina Iordache

The simplification of the plant cultures range and the yields in the last 10-15 years brings into the actuality the role of crop rotation andof fertilization on the yield level and stability for wheat and maize even on the soils with a high natural fertility. The results of the researchesperformed between the years 2006 – 2009 on a cambic low gleyed chernozem from the Banat Plain showed that the wheat cultivated inmonoculture gives productions with 59-81% lower than that cultivated in crop rotation with other plants during 2-4 years. In maize, the yieldobtained in monoculture is situated behind that obtained in crop rotation with 11-21%. The most favorable crop rotations for wheat wererape-wheat in a 4 years rotation and soybean-wheat in simple rotation of 2 years. In maize, the most favorable was the 2 years rotation(wheat-maize). The mineral fertilization was very efficient both in wheat (11-36%) and maize (9-31%). The organic fertilization with manurewas very efficient for maize, the yields being superior with a mean value by 34% for a 60 t/ha dose and with 16% for 30t/ha. The fertilizationcompensates the negative effect expressed by the monocultivation only in a small measure

2017 ◽  
Vol 76 (4) ◽  
pp. 145-153 ◽  
Author(s):  
Jana Nikitin ◽  
Alexandra M. Freund

Abstract. Establishing new social relationships is important for mastering developmental transitions in young adulthood. In a 2-year longitudinal study with four measurement occasions (T1: n = 245, T2: n = 96, T3: n = 103, T4: n = 85), we investigated the role of social motives in college students’ mastery of the transition of moving out of the parental home, using loneliness as an indicator of poor adjustment to the transition. Students with strong social approach motivation reported stable and low levels of loneliness. In contrast, students with strong social avoidance motivation reported high levels of loneliness. However, this effect dissipated relatively quickly as most of the young adults adapted to the transition over a period of several weeks. The present study also provides evidence for an interaction between social approach and social avoidance motives: Social approach motives buffered the negative effect on social well-being of social avoidance motives. These results illustrate the importance of social approach and social avoidance motives and their interplay during developmental transitions.


2018 ◽  
Vol 5 (2) ◽  
pp. 37-51 ◽  
Author(s):  
O. Demydenko ◽  
Yu. Zapasna ◽  
V. Velychko

Aim. To substantiate the agroecological estimation of the performance of a short crop rotation in conditions of intense and organic system of fertilization on the basis of restoring normative parameters of emission and se- questration of С-СО 2 circulation while using by-products as organic fertilizers in conditions of modern climatic system of the Forest-Steppe of Ukraine. Methods. Field, statistical, laboratory. Results of Investigations. The performance of short crop rotations is determined by the capacity of С-СО 2 balance. Strong inverse correla- tion was found between the capacity of N and the ratio between C and N in the agrocenosis, which demon- strated that enhancing the humifi cation processes (ratio constriction) led to the increase in the capacity of С org balance and the decrease in the capacity level of С-СО 2 balance (enhancing mineralization), related to the reduction in the performance of crops in the agrocenosis of a crop rotation compared to the organic system of fertilization. The capacity of С-СО 2 and С org balance correlates at the medium level of inverse direction, and the yield of the main products, feed units and digestible protein correlates at the level of strong direct correlation. Conclusions. General mineralization of by-products and humus in the agrocenosis and humifi cation processes are antagonists, so extending the ratio between С and N at the intense fertilization system stimulates the in- crease in performance and reducing С to N similar to the organic fertilization system enhances the humifi cation process due to binding of С org into humus and limits mineralization which leads to the reduction in agrocenosis performance at the organic fertilization system.


2016 ◽  
Vol 12 (1) ◽  
pp. 4172-4177
Author(s):  
Abdul Malek

The denial of the existence of contradiction is at the root of all idealism in epistemology and the cause for alienations.  This alienation has become a hindrance for the understanding of the nature and the historical evolution mathematics itself and its role as an instrument in the enquiry of the physical universe (1). A dialectical materialist approach incorporating  the role of the contradiction of the unity of the opposites, chance and necessity etc., can provide a proper understanding of the historical evolution of mathematics and  may ameliorate  the negative effect of the alienation in modern theoretical physics and cosmology. The dialectical view also offers a more plausible materialist interpretation of the bewildering wave-particle duality in quantum dynamics (2).


2020 ◽  
pp. 26-28
Author(s):  
Н.Т. Чеботарев ◽  
Н.Н. Шергина

Пахотные угодья Республики Коми в основном представлены дерново-подзолистыми почвами с низким естественным плодородием, которые без применения удобрений быстро подвергаются деградационным процессам, что резко снижает их продуктивность. Цель исследований: оценка эффективности долговременного применения органических и минеральных удобрений при выращивании картофеля в кормовом севообороте в условиях Республики Коми. Методической основой выполнения работ были комплексные исследования дерново-подзолистых почв, клубней картофеля на участках многолетнего полевого эксперимента, заложенного на землях Института агробиотехнологий ФИЦ Коми НЦ УрО РАН в соответствии с «Методическими указаниями географической сети опытов с удобрениями». Длительный период исследований (более 40 лет) характеризовался различными климатическими условиями, которые отразились на количестве урожая и качестве клубней картофеля. Было проведено 7 ротаций (14 лет) с выращиванием картофеля. Вносили органические удобрения – торфонавозный компост (ТНК) в дозах 40 и 80 т/га (1 и 2 фон, соответственно) под картофель и минеральные удобрения – NPК в дозах 1/3; 1/2 и 1 для восполнения выноса растениями элементов питания. Установлено положительное влияние комплексного применения органических и минеральных удобрений на урожайность и качество картофеля, а также на плодородие дерново-подзолистой легкосуглинистой среднеокультуренной почвы в кормовом севообороте в почвенно-климатических условиях Республики Коми. В результате применения шестипольного севооборота и комплексного внесения удобрений с 1978 года к 2019 году в почвах снизилась обменная и гидролитическая кислотность; повысилось содержание гумуса на 0,5% (в контроле); на 0,2–0,5% (с тремя дозами минеральных удобрений); на 0,3–1,1% (с ТНК); на 0,2–1,6% (при совместном применении органических и минеральных удобрений). Наибольшие урожаи картофеля получены при совместном применении органических (80 т/га) и минеральных удобрений (1 NPК) и составили 37,1 т/га клубней (8,5 тыс/га кормовых единиц). При таком соотношении удобрений показано высокое качество клубней картофеля: содержание крахмала 15,5%, витамина С – 19,4 мг%, сырого протеина – 14,1%. Количество нитратного азота не превышало ПДК (ПДК 250 мг.с.м.). Экономические расчеты показали, что при внесении ТНК 40 т/га + 1 NPК в дерново-подзолистые почвы с.-х. использования в среднетаежной зоне Республики Коми при выращивании картофеля, условный чистый доход составит 68,4 тыс. р. с 1 га, себестоимость 1 т картофеля – 2,8 тыс. р., рентабельность 188,7%. The arable land of the Republic of Komi is mainly represented by dern-sub-ground soils with low natural fertility, which without the use of fertilizers are quickly subjected to degradation processes, which dramatically reduces their productivity. The aim of the research is to evaluate the efficiency of long-term use of organic and mineral fertilizers in the growing of potatoes in feed crop rotation in the conditions of the Komi Republic. The methodological basis for carrying out the works was comprehensive studies of dern-subhead soils, potato tubers on the sites of a multi-year field experiment laid on the lands of the Institute of Agrobiotechnology of the FRC Komi SC UB RAS in accordance with the «Methodological Instructions of the Geographical Network of Experiments with Fertilizers». A long period of research (more than 40 years) was characterized by different climatic conditions, which affected the number of crops and the quality of potato tubers. There were 7 rotations (14 years) with potato cultivation. Organic fertilizers – peat-avous compost (TNK) in doses of 40 and 80 t/ha (1 and 2 background, respectively) for potatoes and mineral fertilizers – NPK in doses of 1/3; 1/2 and 1 to replenish the carry-out of food elements by plants. The positive effect of the integrated use of organic and mineral fertilizers on the yield and quality of potatoes, as well as on the fertility of soddy-podzolic light loamy medium cultivated soil in fodder crop rotation in the soil and climatic conditions of the Komi Republic, has been established. As a result of the use of six-bed crop rotation and the integrated application of fertilizers, metabolic and hydrolytic acidity decreased in soils from 1978 to 2019; humus content increased by 0.5% (in control); 0.2–0.5% (with three doses of mineral fertilizers); 0.3–1.1% (with TNCs); 0.2–1.6% (with combined use of organic and mineral fertilizers). The largest potato yields were obtained from the combined use of organic (80 t/ha) and mineral fertilizers (1 NPK) and amounted to 37.1 t/ha tubers (8.5 thousand/ha feed units). The largest potato harvests were obtained with the combined use of organic (80 t/ha) and mineral fertilizers (1 NPK) and amounted to 37.1 t/ha of tubers (8.5 thousand/ha of feed units). With this ratio of fertilizers, the high quality of potato tubers was also determined: the starch content was 15.5%, vitamin C – 19.4 mg%, crude protein – 14.1%. The amount of nitrate nitrogen did not exceed the MPC (MPC 250 mg.s.m.). Economic calculations showed that if TNK is added 40 t/ha 1 NPK to the dern-sub-ground soils of agricultural use in the medium-sized zone of the Komi Republic when growing potatoes, the conditional net income will be 68.4 thousand rubles from 1 ha, the cost of 1 t of potatoes – 2.8 thousand rubles, profitability 188.7%.


2012 ◽  
pp. 66-77 ◽  
Author(s):  
I. A. Lavrinenko ◽  
O. V. Lavrinenko ◽  
D. V. Dobrynin

The satellite images show that the area of marshes in the Kolokolkova bay was notstable during the period from 1973 up to 2011. Until 2010 it varied from 357 to 636 ha. After a severe storm happened on July 24–25, 2010 the total area of marshes was reduced up to 43–50 ha. The mean value of NDVI for studied marshes, reflecting the green biomass, varied from 0.13 to 0.32 before the storm in 2010, after the storm the NDVI decreased to 0.10, in 2011 — 0.03. A comparative analysis of species composition and structure of plant communities described in 2002 and 2011, allowed to evaluate the vegetation changes of marshes of the different topographic levels. They are fol­lowing: a total destruction of plant communities of the ass. Puccinellietum phryganodis and ass. Caricetum subspathaceae on low and middle marches; increasing role of halophytic species in plant communities of the ass. Caricetum glareosae vic. Calamagrostis deschampsioides subass. typicum on middle marches; some changes in species composition and structure of plant communities of the ass. Caricetum glareosae vic. Calamagrostis deschampsioides subass. festucetosum rubrae on high marches and ass. Parnassio palustris–Salicetum reptantis in transition zone between marches and tundra without changes of their syntaxonomy; a death of moss cover in plant communities of the ass. Caricetum mackenziei var. Warnstorfia exannulata on brackish coastal bogs. The possible reasons of dramatic vegetation dynamics are discussed. The dating of the storm makes it possible to observe the directions and rates of the succession of marches vegetation.


2015 ◽  
Vol 14 (1) ◽  
pp. 20
Author(s):  
Wan Asrida ◽  
Dian Arival Aryadana

This research is intended to find out the role of the regional environmental impact Control Agency of Batam City against the environmental problems that occur in industrial areas namely, Batam city, concerning sustainable development based upon the environment, the activities of the industry now aims to build an economic sector but has a negative effect that is the pollution of the environment. In this case in Batam city frequent occurrence of environmental pollution caused by industrial activity namely with disposal of waste which are not in place. This research is focused on environmental impact Control Agency area of Batam city authorities in the control of the environment . With the outline of the research issues namely how environmental impact Control Agency the role of the Regions in the control of pollution of the environment against industrial activity in Batam city in 2011-2014 and the factors restricting the role of the regional environmental impact Control Agency in controlling environmental pollution in Batam city in 2011-2014.Type of this research is a descriptive i.e. researchers provide a description and overview of the phenomenon or social symptoms examined by independent variables described in a systematic and accurate. Method of data collection is done by means of interviews and the documentation.The results of this research show that the role of environmental impact Control Agency area of Batam city in pollution control against industrial activity carried out according to its function but have not run well in accordance with the goals and targets that have been set. This is not in accordance with the duties and functions of the regional environmental impact Control Agency of Batam city, resulting in less the maximum role of Bapedalda itself in controlling pollution that occurred in Batam city. So it should be should be able to stake Bapedalda holder which is professional in the discharge of pollution control and must be capable of tackling the obstacles faced.


2004 ◽  
Vol 35 (2) ◽  
pp. 119-137 ◽  
Author(s):  
S.D. Gurney ◽  
D.S.L. Lawrence

Seasonal variations in the stable isotopic composition of snow and meltwater were investigated in a sub-arctic, mountainous, but non-glacial, catchment at Okstindan in northern Norway based on analyses of δ18O and δD. Samples were collected during four field periods (August 1998; April 1999; June 1999 and August 1999) at three sites lying on an altitudinal transect (740–970 m a.s.l.). Snowpack data display an increase in the mean values of δ18O (increasing from a mean value of −13.51 to −11.49‰ between April and August), as well as a decrease in variability through the melt period. Comparison with a regional meteoric water line indicates that the slope of the δ18O–δD line for the snowpacks decreases over the same period, dropping from 7.49 to approximately 6.2.This change points to the role of evaporation in snowpack ablation and is confirmed by the vertical profile of deuterium excess. Snowpack seepage data, although limited, also suggest reduced values of δD, as might be associated with local evaporation during meltwater generation. In general, meltwaters were depleted in δ18O relative to the source snowpack at the peak of the melt (June), but later in the year (August) the difference between the two was not statistically significant. The diurnal pattern of isotopic composition indicates that the most depleted meltwaters coincide with the peak in temperature and, hence, meltwater production.


2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Li Chen ◽  
Fengxia Zhu ◽  
Murali Mantrala

Purpose This paper aims to systematically investigate the direct and indirect effects of four types of support – peer instrumental support, peer emotional support, platform business support and platform communication support – on seller trade volume in social commerce. It also aims to uncover the path of support-to-sales of the seller from a platform perspective and provides a more complete picture of the social commerce phenomenon. Design/methodology/approach This paper uses multi-source data including primary survey data and secondary data on trade volume to test the hypotheses. PROCESS mediation model is used to analyze the multi-source data set. Findings This study finds that the positive effects of peer instrumental support, platform business support and platform communication support on seller trade volume are fully mediated by seller collaborative information exchange. Also, peer emotional support has a significant negative effect on seller trade volume and collaborative information exchange can serve as a buffer to mitigate the negative effect. Research limitations/implications The authors provide new insights into what types of support are or are not conducive to improving transaction volume of individual sellers and highlight the mediating role of seller information exchange in this value generation process in social commerce. These findings advance current knowledge of how seller interactions increase value in social commerce. The chosen research setting may limit the generalizability of the findings of this study. Practical implications This paper offers valuable implications for social commerce platforms on how to better serve their sellers to achieve high growth. Specifically, the findings suggest that platforms should encourage instrumental support and information exchange among peer sellers. In addition, platforms should expand seller support from a single-focus on sellers’ business to a dual-focus on both sellers’ business and socialization in social commerce. Originality/value This paper fulfills an identified need to study how sellers can better derive value from the social interactions and how social commerce platforms can effectively influence transactions, support sales and serve as a selling platform.


2021 ◽  
Vol 83 (8) ◽  
Author(s):  
F. Al Basir ◽  
Y. N. Kyrychko ◽  
K. B. Blyuss ◽  
S. Ray

AbstractMany plant diseases are caused by plant viruses that are often transmitted to plants by vectors. For instance, the cassava mosaic disease, which is spread by whiteflies, has a significant negative effect on plant growth and development. Since only mature whiteflies can contribute to the spread of the cassava mosaic virus, and the maturation time is non-negligible compared to whitefly lifetime, it is important to consider the effects this maturation time can have on the dynamics. In this paper, we propose a mathematical model for dynamics of cassava mosaic disease that includes immature and mature vectors and explicitly includes a time delay representing vector maturation time. A special feature of our plant epidemic model is that vector recruitment is negatively related to the delayed ratio between vector density and plant density. We identify conditions of biological feasibility and stability of different steady states in terms of system parameters and the time delay. Numerical stability analyses and simulations are performed to explore the role of various parameters, and to illustrate the behaviour of the model in different dynamical regimes. We show that the maturation delay may stabilise epidemiological dynamics that would otherwise be cyclic.


2021 ◽  
Vol 41 (2) ◽  
Author(s):  
Blessing Mhlanga ◽  
Laura Ercoli ◽  
Elisa Pellegrino ◽  
Andrea Onofri ◽  
Christian Thierfelder

AbstractConservation agriculture has been promoted to sustainably intensify food production in smallholder farming systems in southern Africa. However, farmers have rarely fully implemented all its components, resulting in different combinations of no-tillage, crop rotation, and permanent soil cover being practiced, thus resulting in variable yield responses depending on climatic and soil conditions. Therefore, it is crucial to assess the effect of conservation agriculture components on yield stability. We hypothesized that the use of all three conservation agriculture components would perform the best, resulting in more stable production in all environments. We evaluated at, eight trial locations across southern Africa, how partial and full implementation of these components affected crop yield and yield stability compared with conventional tillage alone or combined with mulching and/or crop rotation. Grain yield and shoot biomass of maize and cowpea were recorded along with precipitation for 2 to 5 years. Across different environments, the addition of crop rotation and mulch to no-tillage increased maize grain by 6%, and the same practices added to conventional tillage led to 13% yield increase. Conversely, adding only mulch or crop rotation to no-tillage or conventional tillage led to lower or equal maize yield. Stability analyses based on Shukla’s index showed for the first time that the most stable systems are those in which mulch is added without crop rotation. Moreover, the highest yielding systems were the least stable. Finally, additive main effects and multiplicative interaction analysis allowed clarifying that mulch added to no-tillage gives stable yields on sandy soil with high rainfall. Similarly, mulch added to conventional tillage gives stable yield on sandy soil, but under low rainfall. This is the first study that highlighted the crucial role of mulch to enhance the stability and resilience of cropping systems in southern Africa, supporting their adaptability to climate change.


Sign in / Sign up

Export Citation Format

Share Document