TENDENCIES OF CLIMATIC INDICES IN THE ROMANIAN IRRIGATION SYSTEMS

The aim of this investigation was to evaluate the tendencies of climate aridity of areas where irrigation systems are present, based on meteorological parameters such as precipitations, potential evapotranspiration and water deficit as expressed by the average value of the ratio between precipitation and potential evapotranspiration (P/ETP). The impact of climate changes was done by comparing the time periods of 1961–2000 with 2001–2016, at NUTS5 level where there is potential for crop irrigation. The results showed that for the time period of 2001–2016, the mean values of precipitations decreased down to399 mm, and the potential evapotranspiration increased up to716 mm. Therefore, the water deficit expressed as average value of the ratio P/ETP decreases from 0.594 to 0.557. There is a higher water deficit in most areas where the irrigation systems are present, and, therefore, the near future trend is to increase the water deficit over time

LONG TERM NITROGEN AND PHOSPHORUS FERTILIZATION INFLUENCE UPON SOIL

The paper presents the results obtained in the SCDA Secuieni long term experimental field. The effect of long term (42 years) nitrogen and phosphorus fertilization upon soil fertility and yield was followed up with 0, 40, 80, 120, and 160 kg N/ha and 0, 40, 80, 120, 160 kg P/ha doses. Long term fertilization led to a statistically significant increase of grain yield. Harvest increased from 5,569 kg/ha in the unfertilized control to 9,805 kg/ha in the N160P160 fertilized variants. Each kilogram of phosphorus brought a 6.78 kg corn grain gain, and for each kilogram of nitrogen a 15.28 kg corn grain increase was obtained. Phosphorus long term fertilization significantly increased the total and mobile soil phosphorus content: from 0.0160% in the unfertilized control to 0.094% in the variants fertilized with 160 kg P/ha, respectively from 8 mg PAL/kg in the unfertilized control to 144 mg PAL/kg in the variants fertilized with 160 kg P/ha, and didn`t significantly change total and mobile potassium level. No significant humus and nitrogen levels modifications occur under the influence of nitrogen and phosphorus long term fertilization

Use of groundwater for irrigation in Romania

The National Land Improvement Agency has in its administration a number of 296 irrigation systems which cover a total land area of 2998255 of hectares. The main source of water for irrigation systems in Romania is the Danube River, followed by smaller rivers and water reservoirs. According to the data presented in this study, in Romania for all five studied years the effectively used groundwater volume for irrigation was smaller than the required volume. Also there is an annual tendency of growing of the effectively used groundwater volume. For the year of 2015 a volume of 6148.07 cubic meters of groundwater were used for irrigation of an area of 10089 hectares. From the data reported in this study it can be observed that a village from Tulcea county has an irrigated area of 2023 hectares with groundwater, representing about 65 % from the total arable area. The largest area where irrigation with groundwater was applied was recorded within the villages of Galati county, over half of the total irrigated area of 10089 hectares. It is well known that Galati county is one of the largest vegetable basins of our country, which is located around the Matca village

Brief Announcement: Black-Box Concurrent Data Structures for NUMA Architectures

Recent work introduced a method to automatically produce concurrent data structures for NUMA architectures. We present a summary of that work

MINERAL FERTILIZATION BY APPLYING OPTIMUM NITROGEN DOSES AT FARM LEVEL

An important measure included in the Code of Agricultural Practices is related to the standards on maximum quantities of nitrogen fertilizers which may be applied on agricultural lands in order to prevent or reduce nitrates pollution of water bodies. For this, fertilizer plans at farm level are reccomended to be carried out. The case study is accomplished within a farm located in Ialomita watershed. This paper shows a fertilization plan obtained by using best practices for efficiently nitrogen use at farm level. Different indicators were needed: expected crop yield at farm level, soil indicators and coefficients of nitrogen use. As much the difference between applied applied nitrogen and exported nitrogen is lower within the farm, as much the nitrogen use efficiency is higher. In case of wheat, the optimum economic nitrogen dose recommended for obtaining 8000 kg/ha is 138 kg/ha of nitrogen. This dose is correlated with the optimum soil nitrogen supply, plant nitrogen need and the lower risk of nitrogen losses in water bodies

Contributions regarding knowledge of soil aeration processes to plant growth and development

In this paper, the potential aeration conditions of the soils are studied, which are particularly important in establishing their fertility status necessary for optimal plant development. The indicators that define the air content of the soil, different forms of porosity are thus analyzed, with emphasis on aeration porosity, pore size distribution, air content at different suction stages, but also some measured indicators (such as air permeability), which define air movement by convection (mass flow). Within the current agricultural technological systems, the different ways of working the soil significantly influence the state of aeration. This process takes place by damaging the soil matrix, by changing the movement of water in the porous space, by the dynamics of biological processes in the soil or by the combined effect of these phenomena. In order to obtain the information necessary for the study and research of soil aeration processes, we approached different methods, namely: direct measurement methods on soil samples collected in experiments with controlled traffic and in expeditionary studies, as well as indirect assessment methods using the existing information in the network of monitoring

Evaluation of soil water regime in the viable irrigation systems from Romania

The aim of this study was to evaluate the active soil moisture range, soil water deficit, and water requirements for plant consumption at agricultural parcel level (NUTS5) where irrigation is applied. In order to evaluate the active soil moisture range, soil water deficit, and water requirements for plant consumption, the method used values of hydrophysical indices (field capacity, wilting point, and active soil moisture range), potential evapotranspiration according to Thornthwaite equation and climatic data for the time period 1961-2014. The evaluations of the different indicators were done at agricultural parcel level fitted within the viable irrigation systems. Irrigated agricultural parcels (NUTS5) are located mostly in the viable irrigation systems from Romanian Plain, south of Moldavia and Dobrogea. The obtained results showed a high variation of the active soil moisture range values. Low values are recorded especially in viable irrigation systems from south part of the country. High and very high values are recorded in eastern and south-eastern part of the country. There is a high water deficit in the most areas of the viable irrigation systems which require irrigation application. High values of water requirement were recorded in south and south-east. This means that there is a high water demand for crop consumption, especially during drought periods

AN ASSESSMENT OF THE EFFECTS OF CRUDE OIL POLLUTION ON SOIL PROPERTIES

Pollution caused by crude oil is the most prevalent problem in the environment. The release of crude oil into theenvironment by oil spills is receiving worldwide attention. The effect of crude oil pollution on soil properties wasinvestigated by achieving a case study in Perisoru, Braila County. It has been achieved a profile until 120 cm and soilsamples were collected according to the methodology and analyzed for some physical and chemical properties. In caseof physical analysis, the values obtained for granulometric fractions were not influenced by the presence of crude oil.Results obtained showed variation in chemical properties of soil. Organic carbon increased from 2.23% for anunpolluted soil to 5.51% in polluted soil. C/N ratios increased from 13.01 for an unpolluted soil to 20.54 in pollutedsoil. Mobile phosphorous and potassium registered in polluted soil similar values with the one characteristic forunpolluted soil. Crude oil at high pollution levels inhibited the growth of crops