نتایج جستجو برای: current soil p test methods such olsen
تعداد نتایج: 5069783 فیلتر نتایج به سال:
in a greenhouse experiment, changes in inorganic phosphorus fractions as well as their availability in the rhizosphere of rice (oryza sativa c.v. khazar) crop, following an application of 40 mg p (as monocalcium phosphate per kg of soil) were investigated in paddy soils north of iran. the study was performed as a 14×2 factorial in a completely randomized design of two factors namely: soil at 14...
Abstract Background Organic farmers frequently report sufficient yield levels despite low or even very soil phosphorous (P) contents questioning the applicability of widely used laboratory methods for P testing organic farming. Aims The aim this study was to compare validity a broad range different extraction on soils under management from South West Germany and test correlation measured concen...
implicit and unobserved errors and vulnerabilities issues usually arise in cryptographic protocols and especially in authentication protocols. this may enable an attacker to make serious damages to the desired system, such as having the access to or changing secret documents, interfering in bank transactions, having access to users’ accounts, or may be having the control all over the syste...
In many intensive agroecosystems continued inputs of phosphorus (P) over many years can significantly increase soil P concentrations and the risk of P loss to surface waters. For this study we used solid-state 31P nuclear magnetic resonance (NMR) spectroscopy, high-power decoupling with magic angle spinning (HPDec-MAS) NMR, and cross polarization with magic angle spinning (CP-MAS) NMR to determ...
rhizosphere has different chemical and biological properties from the bulk soil. information about phosphorus (p) availability in the rhizosphere soils treated with municipal sewage sludge (mss) is limited. therefore, the objectives of this research were to evaluate the rhizospheric effects of wheat (triticum aestivum l.) on phosphorus availability and biological properties in 10 calcareous soi...
this thesis attempts to measure learning styles, self efficacy and intrinsic motivation as predictors of iranian ielts reading comprehension. in order to address this issue, a quantitative study was conducted on some randomly selected intact students at ferdowsi university. these two groups were assigned as they were undergraduate (ba=91) and graduate (ma =74) students; they were all aged betwe...
Monitoring soil phosphorus (P) changes under continuous cropping over decades is an important agronomic and environmental issue. The aim was to determine soil P dynamics in the plough layer as a function of cumulative P budgets (Bcum) across extended cropping periods (7, 12, and 17 yr) for four rates of mineral P fertilization. This field experiment was established in 1975 on a slightly alkalin...
the overgrazing and excessive utilization of rangelands has caused vegetationand soil degradation in many rangelands. in the rangeland management, the soil andvegetation elements, environmental factors and livestock should be considered as decisionmaking agents. various methods are applicable for the rangeland restoration as contourfurrows and mortar stone dam. in order to evaluate the effects ...
soil condition to those characteristics suitable (fit) for a particular land use. Also implicit in this brief definition Information on soil conditions in New Zealand is needed to assess is the capacity for the soil to maintain its fitness into soil quality at a national scale. We tested a standard set of 16 primary indicators at 29 sites (0–10 cm depth) across nine soil great groups the future...
To guide soil fertility investment programmes in sub-Saharan Africa, better understanding is needed of the relative importance of soil and crop management factors in determining smallholder crop yields and yield variability. Spatial variability in crop yields within farms is strongly influenced by variation in both current crop management (e.g. planting dates, fertilizer rates) and soil fertili...
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