جستجوی مقالات مرتبط با کلیدواژه "nutrients" در نشریات گروه "منابع طبیعی"

Shrubs with diverse ecological functions cover a large area of arid and semi-arid lands. Evaluation of changes in soil properties in shrublands can be effective in understanding the ecological relationships of these biomes and their nutritional status for land management. In this research, the spatial changes of soil fertility characteristics based on patch structure and open spaces between patches were studied in pure shrubs including Artemisia sieberi, Scariola orientalis and Astragalus myriacanthus types located in the ari lands of the central plateau of Iran. The evaluation of soil yield characteristics and soil quality was investigated by selecting the reference open space between the patches and recording the morphological characteristics of the patches to study the relationship between them. The results showed that the properties of organic matter, nitrogen, phosphorus and soil quality index (SQI) had the most significant changes between the type of shrubland and in the space between patches in each type (P<0.01). The highest value of the soil quality index was related to the under canopy in A. myriacanthus type and was equal to 0.87, and the lowest value was related to the central point of the open space in A. sieberi type and was equal to 0.22. The functional characteristics of plants such as biomass, height and canopy showed the highest correlation with the spatial distribution of elements and soil fertility factors in the open space areas (P<0.05).

In this research, one of the most important functions and services of the forest, the function of maintaining soil nutrients in the forests of the Dalab watershed in Ilam province, has been valued. First, the amount of erosion and sedimentation in the study area was checked using the modified MPSIAC model in the current condition. By developing two scenarios of converting the (current) natural forest with 30 to 50% canopy cover to bare land through scoring the model, the changes in the amount of erosion and sedimentation were estimated. Next, the amount of soil nutrients was determined by soil sampling and laboratory analysis. Then, taking into account the difference in the amount of erosion in the state of natural forest (current) with 30-50% canopy cover and bare land, the amount of each nutrient element in the soil, and the loss of soil nutrients was also calculated. Then, using the replacement cost method, the service value of forest ecosystem soil nutrient maintenance was estimated. The results showed that the studied forest can maintain 2.52 tons of phosphorus, 35.55 tons of potassium, and 251.96 tons of nitrogen per year with an approximate value of 2,275,700 million rials per year and prevent its loss due to erosion. Also, the value of each hectare of forest for this function was estimated at 88.13 million rials. The estimation of the value of this ecosystem service in Zagros forests indicates the very effective role of forest ecosystems in controlling erosion and protecting soil nutrients.

The ‌application ‌of ‌organic ‌fertilizers ‌in ‌agriculture, ‌especially ‌in ‌soils ‌with ‌poor ‌nutrients, ‌compared ‌to ‌the ‌use ‌of ‌chemical ‌and ‌mineral ‌fertilizers ‌has ‌positive ‌effects ‌on ‌plant ‌growth ‌and ‌yield. ‌The ‌present ‌study ‌was ‌conducted ‌to ‌investigate ‌the ‌effect ‌of ‌the ‌application ‌of ‌vinasse ‌obtained ‌from ‌sugarcane ‌waste ‌on ‌nutrient ‌uptake, ‌growth ‌properties ‌and ‌yield ‌of ‌basil ‌which ‌was ‌carried ‌out ‌in ‌the ‌research ‌greenhouse ‌of ‌Lorestan ‌University ‌in ‌2018. ‌Treatments ‌included ‌five ‌levels ‌of ‌vinasse ‌application: ‌0, ‌0.19, ‌0.38, ‌0.57 ‌and ‌0.76 ‌(w.w) ‌in ‌soil. ‌The ‌results ‌showed ‌that ‌with ‌increasing ‌vinas ‌application, ‌the ‌concentration ‌of ‌nutrients ‌in ‌the ‌plant ‌enhanced. ‌As ‌the ‌vinasse ‌application ‌of ‌0.76 ‌(w.w), ‌the ‌concentration ‌of ‌nitrogen, ‌phosphorus ‌and ‌potassium ‌in ‌the ‌shoot ‌was ‌1.16, ‌1.25 ‌and ‌1.28 ‌folds ‌and ‌in ‌the ‌root ‌1.34, ‌1.30 ‌and ‌1.49 ‌folds ‌more ‌than ‌control, ‌respectively. ‌The ‌highest plant ‌height, ‌root ‌length, ‌leaf ‌area, ‌number ‌of ‌leaves, ‌and ‌leaf ‌chlorophyll ‌index ‌were ‌also ‌observed ‌in ‌0.76 ‌(w.w), ‌which ‌were ‌2.6, ‌2.8, ‌1.8, ‌3 ‌and ‌2.5 ‌folds ‌higher ‌than ‌control, ‌respectively. ‌The ‌dry ‌matter ‌yield ‌of ‌shoot ‌and ‌root ‌in ‌0.76 ‌(w.w) ‌also ‌increased ‌20 ‌and ‌25 ‌folds ‌compared ‌to ‌the ‌control, ‌respectively, ‌while ‌these ‌values ‌for ‌fresh ‌weight ‌of ‌shoot ‌and ‌root ‌were ‌5.2 ‌and ‌4.7 ‌folds, ‌respectively. ‌According ‌to ‌the ‌findings ‌of ‌the ‌present ‌study, ‌vinasse ‌can ‌be ‌recommended ‌as ‌an ‌alternative ‌to ‌chemical ‌fertilizers in production of ‌plants ‌such ‌as ‌basil ‌with ‌proper ‌management.

A factorial completely randomized design with two factors including effective microorganisms (EM) at 0, 1% and salinity (at 0.7, 5, 10 and 13.6 dS/m) was conducted in three replication on one year old seedling of pistachio to study the effect of EM on the physiological and biochemical characteristics and nutrient uptake in UCB1 pistachio under salinity stress. Pistachio seedlings have been studied three months after salinity application. The results showed that increasing salinity decreased leaf relative water content, chlorophyll a and b and nitrogen, phosphorus, potassium and calcium content of leaf; it but increased proline, soluble sugars and sodium and chlorine content compared to the control treatment. Results of EM application showed that 1% concentration of this fertilizer increased resistance of UCB1 to salinity stress. Also, the interaction effects of salinity and EM on the relative content of leaf water, proline, chlorophyll b, soluble sugar and nitrogen, phosphorus, potassium, sodium and leaf chlorine were significant. The maximum relative content of water in leaf (87/13%), chlorophyll a (5/83mg/g.FW), chlorophyll b (2/93mg/g.FW), nitrogen (3/21%), phosphorus (0/25%), potassium (2/69%) and minimum content of sodium (7/90%) and chlorine (12/73%) was abserved in treatment with 1% EM and salinity 0/7 dS/m. Based on the results of this study, application Effective microorganism can reduce the damages of salinity stress.

This experiment was conducted at Mehrgan Agricultural Research Station, Kermansha, Iran, in 2012. The maize parents of hybrid 704 cultivar was cultivated in a randomized complete block design with three replications. The treatments includes: 1-ammonium nitrate (1/3 before planting and 2/3 after planting) 2-solupotas 3-iron chelate, 4-zinc sulfate, 5-manganes sulfate 6- boric acid, 7- Combine treatments 1 to 6 with each other. 8- Combine treatments 1 and 2 with each other. 9- Combine treatments 3 to 6 with each other. 10- Control (without spraying). The applied treatments were sprayed in three stages: 1- growth stage from 6 to 8 leaves 2- maximum leaf area index 3- after pollination. The length of plots was 7 meters and width was 4.5 meters (including 4 mother line and 2 father line) with spacing rows of 75 cm and plant spacing on the 18 cm row. The cultivation was carried out on May 1 and irrigation system was sprinkler. The treats measured was include macro and micro elements in seed, germination percentage, seedling vigor index (SVI), germination rate and Seedling growth rate (SGR) for each treatment. The results showed that foliar application did not significantly differ in the amount of nutrients in corn seed. Despite the lack of significant difference in the amount of nutrients in the seed, seedling growth and germination rate were superior in some treatments, so that the highest seedling growth was observed in potassium spraying treatment. The highest rate of germination was also due to spraying with high consumption elements.

In order to determine the effects of the foliar applicationof ureaand micro elements during growth periods of maternal plants on germination, vigor and greening of produced chickpea seeds (Kabuli), an experiment was carried out in a randomized complete block design with 12 treatments and three replications at the Agricultural Faculty Research Station, Ferdowsi university of Mashhad during 2013-2014. The treatments consisted of foliar applicationat six levels: control (foliar application with water); foliar applicationof urea (2 %); foliar applicationof urea + (2%)  Zinc (2 per thousand); foliar applicationof urea (2%) + Iron sulfate (3 per thousand); foliar applicationof urea (2%) + Zinc (2 per thousand) and iron (3 per thousand); foliar applicationwith urea+ complete fertilizer (3 per thousand micro-elements containing 500 ppm) and foliar applicationwith two levels, sprayed once at the beginning of flowering and sprayed twice namely, one at the beginning of flowering and one at seeding stage that include 12 treatments in total. The result showed that foliar application was not significant on germination percentage and maximum speed of germination using two times  foliar application of urea + Zinc+ iron and foliar applicationwith urea+ complete fertilizer in flowering and seeding time treatments, respectively. Two times offoliar application using urea + zinc + iron had the highest impact on the vigor index.

This study was carried out as completely randomized block in order to study influence of fourpoplar clone plantation on availability of some soil nutrients in Safrabasteh (Astaneh, Guilan Province). Four poplar clones as: 1.Populus euruamerican 214 2.Populus euruamerican 45/51 3.Populus deltoeides77/51 4.Populus deltoeides69/55 were selected in Safrabasteh Poplar Research Station. pH, O.M, N, P, K, Ca and Mg in rhizosphere soil were determined. Results show that difference between clones are significant on soil nutrients except N and Ca. Means comparison show that the Populus euruamerican 45/51 had greater effects on the soil parameters. Comparison the growth characteristics the minimum diameter and height of 15 cm and 12.9 m respectively, with p.e45.51 is dedicated to clone which may indicate less use of plant nutrients to the soil is mostly or returned.