Plant Availability of Cadmium in Soils: I. Extractable Cadmium in Newly and Long-Term Cultivated Soils

Abstract

Effects of long-term use of phosphate fertilizers on extractable soil Cd in relation to its concentrations in plants were investigated. “Paired” soil samples were collected from newly and long-term cultivated fields and analyzed for Cd by extraction with NH₄OAc, DTPA, NH₄OAc-EDTA, NH₄NO₃, HCl and CaCl₂. Plant samples were also collected and analyzed for Cd. Significant differences in extractable Cd by all the extractants except NH₄NO₃ were observed between the newly and long-term cultivated soils. The Cd concentrations in plants were not increased by the elevated extractable Cd. Although significant relationships were observed between plant Cd and extractable soil Cd, none of the extractants used alone gave a good assessment of plant-available Cd for all the samples used in this study.     

Plant Availability of Cadmium in Soils: II. Factors Related to the Extractability and Plant Uptake of Cadmium in Cultivated Soils

Abstract

Eighty four soil samples collected from southeastern Norway were analyzed for Cd by extraction with NH₄OAc, DTPA, NH₄OAc-EDTA, NH₄NO₃, HCl and CaCl₂. The total Cd, pH, exchangeable K and Ca, dithionite-extractable Mn, available P and fine sand (0.2–0.02 mm) contents were the principal factors related to the extractable Cd, with some inter-extractant variations. Cadmium extracted by NH₄NO₃, NH₄OAc, HCl and CaCl₂ decreased with increasing soil pH, but the Cd extracted by all the extractants increased with increasing total Cd, exchangeable K and Ca, available P, and Mn-oxide contents in the soils. The Cd concentrations in plants were significantly related to the extractable Cd, exchangeable Ca and Mg, pH, Mn-oxides and organic matter content.     

中国尾孢菌属真菌省级新记录种

为丰富中国真菌地理分布及寄主范围等相关研究,以形态学研究为基础,报道中国尾孢菌属真菌6个省级新记录种,包括湖南省新记录种辣椒尾孢、陕西省新记录种红花尾孢、辽宁省新记录种酸浆尾孢、四川省新记录种车前尾孢和苦苣菜尾孢、及黑龙江省新记录种堇菜尾孢。对这些种分别进行描述,并附有线条图。     

中国缓步动物两新记录种记述

本文记述了中国缓步动物两新记录种,它们是碧绿棘甲熊虫Echiniscus perviridis Ramazzotti,1959和又爪小生熊虫Minibiotus furcatus Ehrenberg,1859。碧绿棘甲熊虫的标本采自秦岭南坡安康地区,个体大小和特征与模式标本完全一致。叉爪小生熊虫的标本采自陕西省秦岭山脉平河梁,与模式标本个体大小相近,特征基本一致,但中国标本口管比模式标本要宽。     

不同有机废弃物提升新围涂地土壤有机碳库与生物活性的效果

为了解不同来源有机废弃物在提升新围涂地土壤有机碳库和生物活性的作用,采用盆栽试验方法开展了为期30周的施用等有机碳量猪粪、鸡粪、水稻秸秆、蔬菜收获残留物、厨余垃圾堆肥、沼渣、猪粪/稻草秸秆堆肥和生活垃圾堆肥等8种有机废弃物后涂地土壤有机碳、易氧化有机碳、稳定态有机碳、水溶性有机碳、微生物生物量碳及土壤酶活性的动态观察。结果表明：施用各种有机废弃物对改善土壤性状均有明显的效果,在提升土壤有机碳库、生物活性及农田碳库管理指数方面以经过生物发酵处理的猪粪/水稻秸秆堆肥、生活垃圾堆肥、餐厨垃圾堆肥和沼渣为佳;其次为猪粪、鸡粪和水稻秸秆;蔬菜收获残留物因主要由新鲜有机物质组成,其稳定性较差,对提升土壤有机碳库和生物活性的效果较差。施用有机废弃物后,土壤碳库、土壤微生物生物量及其他土壤性状可随试验时间发生明显的变化。研究认为,从提升土壤有机碳库和生物活性考虑,在新围涂地改良中应优先施用猪粪/水稻秸秆堆肥、生活垃圾堆肥、餐厨垃圾堆肥和沼渣等有机废弃物。     

浙江省新地理分布种小莕菜和中国新归化种加拿大苍耳

报道了在浙江省湿地调查时发现的2种新记录植物,分别是龙胆科(Gentianaceae)小莕菜(Nymphoides coreanum)和菊科(Compositae)加拿大苍耳(Xanthium canadense).其中,小莕菜是浙江省新地理分布种,加拿大苍耳是中国新归化种.     

茅台酒生态功能保护区贵州省被子植物的6个新记录种

记述了贵州省6个被子植物分布新记录种,分别是猫爪草(Ranunculus ternatus)、雾水葛(Pouzolzia zeylanica)、滑皮石栎(Lithocarpus skanianus)、趾叶栝楼(Trichosanthes pedata)、全育卫矛(Euonymus fertilis)和多苞斑种草(Bothriospermum secundum)。     

山西宽跗食蚜蝇属的新记录种研究

记述了山西宽跗食蚜蝇属的 4个新记录种 :结毛宽跗食蚜蝇Platycheirusalbimanus (Fabricius) ,卵圆宽跗食蚜蝇PlatycheirusovalisBeeker,狭腹宽跗食蚜蝇Platycheirusangustatus (Ietterstedt) ,菱斑宽跗食蚜蝇Platyeiruspeltatus(Meigen)。对每种形态作了记述 ,并附特征图     

Effect of in ovo glyphosate injection on embryonic development,serum biochemistry,antioxidant status and histopathological changes in newly hatched chicks

This study aimed to investigate the potential toxic effects of pure glyphosate or Roundup^® on hatchability, serum biochemistry and histopathological observation of the liver and kidney of newly hatched chicks. On day six, a total of 225 fertile eggs were obtained from Huafeng breeder hens. The eggs were randomly divided into three treatments: (a) the control group injected with deionized water, (b) the glyphosate group injected 10 mg pure glyphosate/Kg egg mass and (c) the Roundup group injected 10 mg the active ingredient glyphosate in Roundup^®/Kg egg. The results showed a decrease of hatchability rate in chicks treated with Roundup^® (66%). In addition, no significant change was observed in body weights, yolk sac weight and relative weight organs except the liver and kidney were significantly increased with groups treated with glyphosate and Roundup^® compared to the control group. The results showed that serum protein profiles were linearly significantly increased of serum phosphor, uric acid, aspirate aminotransferase, alanine transaminase and alkaline phosphatase in groups treated with Roundup^®, as well as the serum concentrations of triglyceride altered after treatment with glyphosate. Furthermore, oxidative stress was observed in the treated chicks, the glyphosate and Roundup^® induced changes of the content of malondialdehyde in both the liver and kidney, moreover decrease of glutathione peroxidase, total superoxide dismutase and catalase activity in the kidney tissue and serum. Additionally, changes also happened in the histomorphology of the liver and kidney tissue of the treated chicks. It can be concluded that Roundup^® as a probable decrease of hatchability. Exposure to glyphosate alone or Roundup^® caused liver and kidney histopathological alterations, serum parameters imbalances and oxidative stress, also induced a variety of liver and kidney biochemical alterations that might impair normal organ functioning in newly hatched chicks.     

新垦耕地土壤有机质含量分析方法的探讨

有机质水平常用作评价土壤肥力的首要指标,如何分析土壤有机质含量对正确评估土壤肥力有重要意义。在探讨现行标准在新垦耕地土壤有机质含量分析中存在问题的同时,提出了相应的改进方法。结果表明,用现行NY/T1121.6-2006标准测定的是以＜2mm土粒为基数的有机质含量;若以包括＞2mm砾石为基数计算时,新垦耕地土壤有机质水平下降了22%（平均值从23.1g/kg降至18.0g/kg）;按照耕地质量评定与分等定级技术规范(DB33/T895—2013),土壤有机质生产能力赋值由0.84分降低到0.4分,属于低水平。研究结果为准确评估新垦耕地土壤有机质含量提供参考。