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A gas chromatographic-tandem mass spectrometric method (GC--MS/MS) has been developed for sensitive and reliable detection of 8 organochlorine pesticide residues in wild L. chuanxiong and chestnut. The target compounds were extracted from both samples and simultaneously rudely cleaned up by water--acetone and dichloromethane. Then, the obtained dichloromethane phase was evaporated to dry, treated with [H.sub.2]S[O.sub.4], centrifuged, evaporated and redissolved in 0.5 mL of benzene for GC--MS/MS detection. When spiked from 5 to 500 µg/kg, the average recoveries of organochlorine pesticides in two kinds of sample ranged from 74.2 to 110.9% with the intra-day RSD of 0.1 to 10.1% and the inter-day RSD of 0.7 to 10.5%. The limit of detection of eight compounds varied from 0.13 to 1.2 µg/kg in two kinds of samples. Keywords: gas chromatographic-tandem mass-spectrometric method, extraction, tracer technique, methionine, benzimidazole DOI: 10.1134/S1061934813030064, Organochlorine pesticides (OCPs) are worldly known for being wildly used in agriculture as insecticides in 20th century and having left residues in rivers, soils, various plants, plant originating products and [...]

ABSTRACT. Agricultural chemicals, such as pesticides and herbicides, play an important role in agricultural operations to control unwanted pests and maximize crop yield. However, these chemicals may also threaten aquatic [...]

ABSTRACT. A primary factor contributing to amphibian declines is the application and accumulation of agricultural chemicals. We examined how a common fungicide, chlorothalonil, affects development in larval northern leopard frogs [...]

Agriculture is considered to be among the economic sectors having the greatest greenhouse gas mitigation potential, largely via soil organic carbon (SOC) sequestration. However, it remains a challenge to accurately quantify SOC stock changes at regional to national scales. SOC stock changes resulting from SOC inventory systems are only available for a few countries and the trends vary widely between studies. Process-based models can provide insight in the drivers of SOC changes, but accurate input data are currently not available at these spatial scales. Here we use measurements from a soil inventory dating from the 1960s and resampled in 2006 covering the major soil types and agricultural regions in Belgium together with region-specific land use and management data and a process-based model. The largest decreases in SOC stocks occurred in poorly drained grassland soils (clays and floodplain soils), consistent with drainage improvements since 1960. Large increases in SOC in well drained grassland soils appear to be a legacy effect of widespread conversion of cropland to grassland before 1960. SOC in cropland increased only in sandy lowland soils, driven by increasing manure additions. Modeled land use and management impacts accounted for more than 70% of the variation in observed SOC changes, and no bias could be demonstrated. There was no significant effect of climate trends since 1960 on observed SOC changes. SOC monitoring networks are being established in many countries. Our results demonstrate that detailed and long-term land management data are crucial to explain the observed SOC changes for such networks. regional inventories | soil organic carbon dynamics modeling | land use history doi/ 10.1073/pnas.1002592107

The soil CO2 evolution and soil air CO2 concentration in the Howland Integrated study (HIFS) site, the Bear Brook Watershed in Maine (BBWM) site and the Letter E Township (Letter E) site, all in Maine, were estimated to characterize soil CO2 in various forest types, many years after the harvest. The major yearly changes in temporal patterns of these characteristics are a function of short-term climatic factors.

Byline: M. Ahmad alias Haji A. Bukhsh, R. Ahmad, A. Ali, M. Ishaque and A. Rehman ABSTRACT Maize hybrids exhibit better potassium use efficiency (KUE) and utilize soil N in [...]

Byline: G. Abbas, J. Z. K. Khattak, A. Mir, M. Ishaque, M. Hussain, H. M. Wahedi, M. S. Ahmed and A. Ullah ABSTRACT Recently, the interest in organic farming is [...]

Byline: S. Akhtar and A. Shoaib ABSTRACT The study was focused on exploring role of six agricultural wastes viz., wheat (Triticum aestivum L.) and rice (Oryza sativa L.) husk, pea [...]

Byline: M. A. Anjum, S. H. Khan, A. W. Sahota and R. Sardar ABSTRACT A total of 487samples (77 and 410 of poultry feed ingredients and poultry feed, respectively) received [...]

Byline: M. Rashid, E. S. Wagchoure, A. U. Mohsin, S. Raja and G. Sarwar ABSTRACT The research work was carried out to determine the effects of oxalic acid (OA) on [...]

Byline: A. R. Butt, S. I. Yaseen and A. Javaid ABSTRACT Stored grains of five varieties of rice (Oryza sativa L.) viz. KS-282, Basmati-385, Basmati-370, Basmati Kernal and Basmati-198 were [...]

The spatial variability in the rate of phenyl-urea herbicide isoproturon degradation within the agricultural lands is investigated. Research shows that the Sphingomonas sp. strains SRS2 and F35 in soil and culture exhibit a narrow pH optimum, 7 to 7.5 pH, for metabolizing the herbicide, suggesting that soil pH stringency leads to spatial variation of the herbicide degradation.

An understanding of soil nutrient pools and their relationship to soil properties and to soil test values should underpin soil tests, but few studies of this type have been conducted for soil B. Boron was fractionated by sequential extraction in 13 soils collected from north (47 [degrees] N) to south (20 [degrees] N) in eastern China. The nonspecifically adsorbed B (NSA-B) and specifically adsorbed B (SPA-B) comprised [is less than] 1% of total B. By contrast, B occluded in Mn oxyhydroxide (MOH-B), in amorphous Fe and Al oxides (AMO-B) and in crystalline Fe and Al oxides (CRO-B) comprised from 0.01 to 7.6% of total B. The content of the NSA-B fraction significantly decreased with increasing mean annual rainfall of the site and increased with increasing soil pH and exchangeable Ca. The MOH-B fraction was positively correlated with soil pH and cation-exchange capacity (CEC), and negatively with rainfall and temperature. The AMO-B fraction was significantly related to amorphous [Fe.sub.2][O.sub.3] and rainfall. The CRO-B fraction was positively correlated with pH and exchangeable Ca, but not with crystalline [Fe.sub.2][O.sub.3]. The SPA-B fraction was not correlated with any soil properties or climate factors. These results emphasize that the forms of B in Chinese soils were distinctly different from those in soils of southeast USA and Greece.