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Water, Air, & Soil Pollution - In the present work, rapid test methods for field screening of soil for Cu, Ni, and Pb content are presented. They are based on commercially obtainable Microquant... 相似文献
84.
为探讨PBAT/PLA全生物降解地膜在新疆棉花上的应用效果,以PE地膜为对照,在新疆石河子垦区开展PBAT/PLA全生物降解地膜应用试验,系统分析了PBAT/PLA地膜的降解性能及其对土壤温湿度、棉花长势和产量的影响。结果表明:PBAT/PLA地膜降解较快,在覆膜43 d即进入诱导期;红外、X射线衍射、扫描电镜等测试也表征出PBAT/PLA地膜田间降解后分子链、晶体结构和微观形貌等发生的一系列变化;在棉花生育前期,PBAT/PLA地膜膜面保持完整,增温保墒效果良好,两组出苗率一致;但随着PBAT/PLA地膜逐渐裂解,其应用效果开始下降,棉花进入盛蕾期后,PBAT/PLA地膜覆盖下土壤温度和含水率比PE地膜覆盖分别低0.30~1.15℃和2.31~3.46个百分点,最终导致PBAT/PLA地膜组的株高和茎粗较PE地膜组分别降低22.08%和12.82%,籽棉减产20.24%。因此,PBAT/PLA全生物降解地膜还需从材料分子链结构层面进行配方改良、推迟降解诱导期、提高棉田覆盖应用潜力,使其能更好在新疆棉花生产中进行试用推广。 相似文献
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分析了东北一熟区、水旱轮作稻区、双季稻区三大稻区的水稻秸秆直接还田配套机具的研究进展,从水稻收获、耕整地两个作业环节指出各区域实施秸秆还田过程中存在的技术难点及待解决问题。目前,长江中下游地区的水稻秸秆直接还田配套机具已经基本满足农艺要求;东北一熟区的秸秆直接还田仍存在很多问题,由于秸秆韧性强、秸秆量大,造成秸秆粉碎抛撒不均匀问题,导致后期整地困难及春季泡田搅浆后秸秆漂浮严重问题,仍是亟需解决的技术难题;南方双季稻及西南稻区由于地势限制导致的机收水平低问题,也同样限制了水稻秸秆直接还田技术的发展。在此基础上,提出了我国水稻秸秆直接还田技术配套机具发展建议,以期为下一步研究解决稻田秸秆还田关键机具问题提供参考。 相似文献
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In recent years there has been an increased focus on sustainable farming systems. This has led to an increase in the use of farm models built to assess the environmental impact from farming. In whole-farm models including crop production it is important to consider the rotation of crops, since this has a major impact on the consequences of the crop production. 相似文献
88.
Kirsti R⊘snes Olavi Junttila Arild Ernstsen Nina Sandli 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):151-155
Abstract Development of cold tolerance in white clover (Trifolium repens L.) genotypes originating from various parts of Norway and grown outdoors at Tromso, latitude 69°39′N, has been studied. Stolon samples for an artificial freezing test and for chemical analysis were collected three times during the autumn. Generally, the most northern genotypes were more cold tolerant than the southern ones. Cold tolerance increased significantly from September to November in all genotypes. Content of dry matter, soluble carbohydrates, sucrose and proline in stolons increased during the hardening process. These changes were similar in both northern and southern genotypes of white clover. 相似文献
89.
Vadim V. Ermakov Elena M. Korobova Alexander P. Degtyarev Sergey F. Tyutikov Elena A. Karpova Nina S. Petrunina 《Journal of Soils and Sediments》2016,16(4):1253-1266
Purpose
The main goal of the study was to evaluate biogeochemical effects of particular factors changing the structure of landscapes due to enhanced mass migration and erosion of the outcropping rocks by studying transformation of chemical composition of the draining waters and flood plain soils; chemical composition of the solid and liquid phases of the Ardon River waters; and by assessing ecological consequences and risk of contamination of the area by heavy metals.Materials and methods
Water, soil, and biota species (plants, algae, and amphibian) were sampled at the plots located up- and downstream the mining and industrial areas of North Ossetia (the Ardon River basin) before and after the mudflow that took place in 2002. The air-dried samples were decomposed in a mixture of mineral acids. Heavy metals were determined by means of AAS with the help of AAS-80 (Hitachi) or AAS-2A (KORTEC) using standard reference materials of hair (CRM 397), plant mixture (SBMT-02), and soil (SRM 2709). Hydrochemical and biochemical analyses were performed with the help of the known methods (Kraynov and Shvets 1992; Burtis et al. 2006).Results and discussion
The study showed that activity of the Misur Mining Combine and its Ardon-Khost tailings caused a significant local increase of Pb, Cd, Cu, and Zn content in soils, water, and biotic components as compared to the background values. The mudflow of 2002 changed the structure of landscapes and was followed by a considerable transformation of chemical composition of the downstream river waters and floodplain soils, and by invasion of particular hydrophyte species. Algae and amphibian adapted to the changed conditions and indicated both natural and anthropogenic transformation of the environment. A distinct relation between the particle size of the suspended matter in the Ardon River waters and water salinity was discovered.Conclusions
Therefore, the Unal basin presents a vivid example of modern natural and anthropogenic evolution of Pb-Zn biogeochemical province under conditions of the extreme and dynamic geochemical environment leading to enhanced risks of ecological damage. Algae species demonstrated high adaptive and indicative capacity in case of both the fast natural and man-made impact.90.
Summary The inheritance of root rot resistance in red raspberry, caused by Phytophtora fragariae var. rubi, was investigated using two experimental breeding designs. Design A was not randomly mated and genetic parameters could not be calculated. Design B was therefore randomly mated to make it possible to do such estimations. Considerable genetic variation was associated with the recorded traits on seedlings tested in a glasshouse. Disease index and % survival were both found to be highly heritable with broad sense heritabilities (H2) close to 0.9 in each design. Estimates of narrow sense heritability (h2), indicated that progress towards resistance would be moderate. In the first design the cultivars Festival, Asker, Boyne and Sentry and the clones N85-02-13 and N85-06-140 had high general combining abilities. Some crosses had a high specific combining ability indicating the presence of non-additive genetic variation. 相似文献