关于主编 关于主编： 侯德义，英国土壤学会（British Society of Soil Science）会刊 《土壤利用与管理》 （ Soil Use and Management ）主编，先后于清华大学、斯坦福大学、剑桥大学获得学士、硕士和博士学位，并在国际咨询公司Parsons工作近10年。2015年回到清华大学环境学院任教，主要从事污染土壤与地下水修复的相关理论和应用研究，并积极参与国家和地方土壤污染相关法律与政策的制定，主持编写多个国际国内技术标准和指南。迄今为止主持国家科技部重大专项课题、国家自然基金面上项目、生态环境部技术指南编制、全国土壤详查技术支撑等项目和课题20余项。目前已在《科学》（ Science ）、《自然》（ Nature ）、《自然·气候变化》( Nature Climate Change )、《自然·可持续发展》（ Nature Sustainability ）等国际权威期刊发表论文100余篇，其中5篇入选ESI热点论文（全球前0.1%），16篇入选ESI高引论文（全球前1%），获16项专利授权和软件著作权。获国家环境保护科学技术二等奖,中国环境科学学会青年科学家奖等荣誉。 以下为访谈整理： 1. As the new Editor-in-Chief of Soil Use and Management , would you please briefly introduce the journal and share your personal vision for the journal? Answer： SCI检索期刊 《土壤利用与管理》 （ Soil Use and Management ）创刊于1985年，现已成为英国土壤学会的两大会刊之一及土壤应用科学领域最权威的国际期刊之一。本刊共由一位主编、两位副主编、以及来自16个国家和地区的45位编委管理。我个人对本期刊愿景是：期刊应大力推动基础科学与决策支撑之间的结合，鼓励发表土壤与气候变化、生物多样性、环境健康、联合国可持续发展目标等相关议题紧密联系的跨学科科研成果，着力提升土壤科学在科学体系中的地位以及国际社会关注度。 2. What advice would you give to authors based in China submitting to the journal？ Answer： 建议作者选择与社会可持续发展密切相关的议题，提出新的科学假设，研究根本性的土壤过程，为土壤的可持续利用与管理提供新的观点及支撑。论文的研究成果应具有较强的普适性或关注较大的空间尺度，以期为全球土壤领域的科研工作者、土壤相关政策制定者及农田土壤管理者提供新思路、新方法、新对策。 3. What arethe journal’s criteria for sending an article out for review and then accepting an article? Answer： 期刊送审的主要标准为：送审论文符合期刊的主旨和范围，具有足够的创新性，研究设计没有较大漏洞，研究成果具有一定普适性，未发现抄袭问题等。论文接收的标准包括：研究的设计和过程严谨，研究结果分析恰当，研究讨论深入，研究结论对读者有足够的启发等。 4. What is the publication speed of the journal? Answer： 本期刊在2018-2019年发表周期（从投稿到在线发表）平均为3-4个月。从2020年年初我成为主编以来，期刊发表周期已成功缩短至2个月左右。 5. Where do you see the most interesting research developing within the field of soil science? Answer： 我个人认为土壤领域令人关注的发展方向包括：1）研究作为最大碳库的土壤对气候变化的影响机制，开发创新性土壤碳库管理方法以达到减缓气候变化的目标；2）探索土壤微观性质、土壤微生物及土壤动物的多样性在自然过程及人为干扰下的变化规律，解析土壤健康对生物多样性及农作物生产的影响机制；3）探明土壤污染对农业生产、地表水及地下水污染、空气质量恶化等的影响规律，研发多介质协同污染防治技术；4）研析可持续的土壤利用与管理对实现2030年联合国可持续发展目标的支撑贡献情况。 6. Could you recommend up to 5 articles (published in the last two years) that you think soil science researchers must read from the journal of Soil Use and Management ? Answer： 隆重推荐以下5篇来自《土壤利用与管理》 （ Soil Use and Management ） 的论文。 1. Ye L, Camps‐Arbestain M, Shen Q, Lehmann J, Singh B, Sabir M. Biochar effects on crop yields with and without fertilizer: a meta‐analysis of field studies using separate controls. Soil Use and Management 2020; 36: 2-18. 全文链接： https://onlinelibrary.wiley.com/doi/full/10.1111/sum.12546 2. Alskaf K, Sparkes DL, Mooney SJ, Sjögersten S, Wilson P. The uptake of different tillage practices in England. Soil Use and Management 2020; 36: 27-44. 全文链接： https://onlinelibrary.wiley.com/doi/full/10.1111/sum.12542 3. Dorji T, Field DJ, Odeh IO. Soil aggregate stability and aggregate‐associated organic carbon under different land use or land cover types. Soil Use and Management 2020; 36: 308-319. 全文链接： https://onlinelibrary.wiley.com/doi/abs/10.1111/sum.12549 4. Boardman J, Vandaele K, Evans R, Foster ID. Off‐site impacts of soil erosion and runoff: Why connectivity is more important than erosion rates. Soil Use and Management 2019; 35: 245-256. 全文链接： https://onlinelibrary.wiley.com/doi/abs/10.1111/sum.12496 5. Bampa F, O'Sullivan L, Madena K, Sandén T, Spiegel H, Henriksen CB, et al. Harvesting European knowledge on soil functions and land management using multi‐criteria decision analysis. Soil use and management 2019; 35: 6-20. 全文链接： https://onlinelibrary.wiley.com/doi/full/10.1111/sum.12506 关于期刊 Soil Use and Management publishes research papers, reviews, short communications and informed comment on the wide range of applications of soil science and provides an international forum for those applying scientific principles to understand and solve important soil problems as they affect cropproduction and environmental issues. 期刊主页： https://onlinelibrary.wiley.com/journal/14752743
The 49th anniversary celebration on the foundation of the Land Development Department let the attenders feel warm, cozy and in ease. Here no formal meeting is held. No leaders make speech to the attenders. The celebration is similar to a family gathering. It's a gala for people from all walks of life in Thailand. People are coming and going as they like. Invited guests include researchers and goverment officials from the neighboring countries. The other particpants include the staffs of the LDD in the state level and the regional level, farmers from this country, students from primary schools and middle schools, pedlars who sell agricultural or processing products. Here the agricultural fertilizer, chemicals and other agricultural tools developed by the LDD are exhibited. Various kinds of flowers, fruits, and vegetables are showcased. Agricultural technology is demontrated. Farmers enquire technician, students watch soil experiments or do experiments by themselves. Everyone can sit at the armchairs surrounded by flowers and fruits to have a rest or take pictures. The celebration has become a gala for people from all walks of life in Thailand. 门外或者门厅的屋角也用鲜花进行装饰Even the wall corners are adorned withflowers 瓜果鲜花燕展示Showcasing flowers and fruits 泰国土地发展局内的庭园The courtyard of Land Development Department (LDD) Technology Demonstration 技术示范 Promotion of the developed products 研制产品展示 Popularization of scientific knowledge 科普宣传 A farmer is consulting the technician 技术人员向农民解答问题 开放的空间,人人可以在这里体验到特别的快乐! Everyone here can enjoy themselves Product selling 产品销售
Simulated nitrogen deposition significantly reduces soil respiration in an evergreen broadleaf forest in western China Shixing Zhou, Yuanbin Xiang, Liehua Tie, Bohan Han, Congde Huang https://doi.org/10.1371/journal.pone.0204661 https://www.researchgate.net/publication/327920145 Abstract Soil respiration is the second largest terrestrial carbon (C) flux; the responses of soil respiration to nitrogen (N) deposition have far-reaching influences on the global C cycle. N deposition has been documented to significantly affect soil respiration, but the results are conflicting. The response of soil respiration to N deposition gradients remains unclear, especially in ecosystems receiving increasing ambient N depositions. A field experiment was conducted in a natural evergreen broadleaf forest in western China from November 2013 to November 2015 to understand the effects of increasing N deposition on soil respiration. Four levels of N deposition were investigated: control (Ctr, without N added), low N (L, 50 kg N ha −1 ·a −1 ), medium N (M, 150 kg N ha −1 ·a −1 ), and high N (H, 300 kg N ha −1 ·a −1 ). The results show that (1) the mean soil respiration rates in the L, M, and H treatments were 9.13%, 15.8% ( P 0.05) and 22.57% ( P 0.05) lower than that in the Ctr treatment (1.56 ± 0.13 μmol·m −2 ·s −1 ), respectively; (2) soil respiration rates showed significant positive exponential and linear relationships with soil temperature and moisture ( P 0.01), respectively. Soil temperature is more important than soil moisture in controlling the soil respiration rate; (3) the Ctr, L, M, and H treatments yielded Q 10 values of 2.98, 2.78, 2.65, and 2.63, respectively. N deposition decreased the temperature sensitivity of soil respiration; (4) simulated N deposition also significantly decreased the microbial biomass C and N, fine root biomass, pH and extractable dissolved organic C ( P 0.05). Overall, the results suggest that soil respiration declines in response to N deposition. The decrease in soil respiration caused by simulated N deposition may occur through decreasing the microbial biomass C and N, fine root biomass, pH and extractable dissolved organic C. Ongoing N deposition may have significant impacts on C cycles and increase C sequestration with the increase in global temperature in evergreen broadleaf forests.
Source title CiteScore SJR SNIP Soil Biology and Biochemistry 4.48 2.382 1.670 Plant and Soil 3.11 1.409 1.307 European Journal of Soil Science 3.10 1.615 1.385 Soil and Tillage Research 3.08 1.303 1.805 Biology and Fertility of Soils 3.05 1.654 1.251 Applied Soil Ecology 2.84 1.196 1.288 European Journal of Soil Biology 2.32 0.911 1.124 Soils and Foundations 2.14 1.623 1.753 Soil Use and Management 2.10 1.097 0.998 Soil Dynamics and Earthquake Engineering 2.05 1.516 1.787 Soil Science Society of America Journal 2.02 1.136 1.082 Journal of Plant Nutrition and Soil Science 2.02 0.838 0.927 Journal of Soils and Sediments 1.98 0.896 0.835 Clean - Soil, Air, Water 1.77 0.635 0.819 Water, Air, and Soil Pollution 1.70 0.632 0.759 Soil Research 1.62 0.847 0.861 Journal of Soils and Water Conservation 1.61 0.888 0.939 Journal of Soil Science and Plant Nutrition This source is Open Access 1.55 0.644 1.140 Canadian Journal of Soil Science 1.53 0.865 0.835 Plant, Soil and Environment This source is Open Access 1.33 0.641 1.098 Applied and Environmental Soil Science This source is Open Access 1.24 0.530 0.709 Soil and Sediment Contamination 1.13 0.484 0.621 Soil Science and Plant Nutrition 1.02 0.418 0.578 Soil Science 0.87 0.487 0.472 Archives of Agronomy and Soil Science 0.86 0.442 0.696 Eurasian Soil Science 0.82 0.393 0.911 Soil and Environment This source is Open Access 0.80 0.329 0.576 Yantu Lixue/Rock and Soil Mechanics 0.74 0.843 0.948 Soil and Water Research This source is Open Access 0.74 0.270 0.669 Acta Agriculturae Scandinavica - Section B Soil and Plant Science 0.73 0.345 0.411 Spanish Journal of Soil Science This source is Open Access 0.65 0.315 0.537 Communications in Soil Science and Plant Analysis 0.62 0.346 0.520 South African Journal of Plant and Soil 0.48 0.313 0.453 Air, Soil and Water Research This source is Open Access 0.37 0.173 0.327 International Journal of Soil Science 0.36 0.119 0.682 Journal of Chinese Soil and Water Conservation 0.27 0.222 0.408 Soil Mechanics and Foundation Engineering 0.25 0.165 0.294 Malaysian Journal of Soil Science 0.24 0.155 0.197 Soils and Rocks This source is Open Access 0.13 0.118 0.299 Journal of the Indian Society of Soil Science 0.13 0.180 0.462 Annual Proceedings Soil and Crop Science Society of Florida (coverage discontinued in Scopus) API Soil and Groundwater Research Bulletin (coverage discontinued in Scopus) Arid Soil Research and Rehabilitation (coverage discontinued in Scopus) ASCE J Soil Mech Found Div (coverage discontinued in Scopus) Australian Journal of Soil Research (coverage discontinued in Scopus) Developments in Soil Science (coverage discontinued in Scopus) Divisional Report - CSIRO, Australia, Division of Soils (coverage discontinued in Scopus) International journal of soil dynamics and earthquake engineering (coverage discontinued in Scopus) Journal of Soil Contamination (coverage discontinued in Scopus) Journal of Soil Sciences (coverage discontinued in Scopus) Polish Journal of Soil Science SOIL SCI.SOC.AMER.PROC. (coverage discontinued in Scopus) Soil Technology (coverage discontinued in Scopus) Soviet Soil Science (coverage discontinued in Scopus) Water, Air, and Soil Pollution: Focus (coverage discontinued in Scopus) CitedScore查询网址: https://www.scopus.com/sources?zone=origin=sbrowse
SoilGrids1km is a first approximation of predictions of soil properties ( organic carbon , pH , texture fractions , coarse fragments , bulk density and CEC ) and soil classes for a global soil mask using automated global soil mapping. These maps will be updated on a regular basis and improved using additional contributed data (soil profiles and covariate layers). The predictions available for download at www.soilgrids.org are presently of limited thematic and spatial accuracy and contain artefacts and missing pixels. As such, their suitability/usability for regional and global environmental models may be limited. Before utilizing these maps for any modelling or decision making, we advise users to check that the confidence limits (soil properties distributed together with the predictions) satisfy the precision requirements of their particular application. We invite all interested parties to help us improve the SoilGrids1km by submitting avalidation report or by contributing georeferenced soil profiles or new covariate data (rasters with global coverage at resolutions of 1 km or better). Furthermore, we welcome any volunteered help in fine-tuning any of the GSIF components: WorldSoilProfiles.org, WorldGrids.org, R packages, WOSIS, and SoilInfo App. Conditions for use of the GlobalGrids1km product are described at www.isric.org under Data usage and citation; the Data Policy of ISRIC, the ICSU-accredited World Data Centre for Soils (WDC-Soils), is described here. SoilGrids1km are registered under the Creative Commons Attribution-Non Commercial International CC BY-NC. This means that: you are free to share (copy and redistribute the material in any medium or format) and adapt (remix, transform, and build up on the material), as long as you give appropriate credit and provide a link to the SoilGrids.org homepage. You may not use these materials for commercial purposes. Every effort has been made to trace copyright holders of the materials used to produce SoilGrids1km. Should we, despite all our efforts have overlooked contributors please contact ISRIC and we shall correct this unintentional omission without any delay and will acknowledge any overlooked contributions and contributors in future updates. Data .
International Soil Reference and Information Centre (ISRIC) World Soil Information is an independent, science-based foundation. The institute was founded in 1966 following a recommendation of the International Soil Science Society (ISSS) and United Nations Educational, Scientific and Cultural Organization (UNESCO). It has a mandate to serve the international community with information about the world’s soil resources to help addressing major global issues. ISRIC is the ICSU World Data Centre for Soils (WDC-Soils) since 1989, a member of the Open Geospatial Consortium (OGC) and collaborates with a wide range of partners worldwide. Data Download .
制作高质量的图表和显示项目 在本贴中，我将介绍制作高质量图表的关键要素以及在 此前帖子 中所介绍的显示信息的重要性。制作高质量的显示项目也许会很耗时，但却是十分必要的，原因有二：其一，为了满足目标期刊的投稿要求；其二，便于自己撰写结果部分。你在显示项目上所画的时间越多，越能说明你对此深思熟虑过。这有助于你用清晰、简洁的方式描述它们的主要特点，进而使读者方便快捷地了解你所阐述的内容。 Good maps and figures can help you avoid excessive writing A picture is worth a thousand words Napoleon Bonaparte (1769-1821) Apart from the abstract and conclusions, the first things I look at in a scientific paper are the maps, figures and diagrams (also called display items). I believe you can tell much about the overall quality of a paper by the quality of these things. In my previous post I described how concise written English can be difficult and time-consuming to achieve. However, it is ultimately worth the effort and seeking help to achieve this because the result is clarity of language that facilitates dissemination of your research. The same can be said for maps, figures and diagrams. The more time spent on them to improve their clarity and ease of viewing, the easier it will be for your reader to see quickly what you are trying to show. Another significant advantage of having precise and clear display items is that it makes it easier to write about your study area and results, which will hopefully contribute to achieving written concision. Among other things, I am a Geographic Information Systems (GIS) analyst and have spent much time making maps, and conducting spatial analysis and presenting the results cartographically. All maps should have an indication of where the area they represent is located. For regional location maps you should always give an indication of the latitude (specifying northern or southern hemisphere) and latitude. This is often done through presenting a graticule (segmented frame) around the region, or sometimes using single latitude and longitude lines nearest to the study area (Figure 1). A scale bar should be used. More detailed maps must have a scale bar, north arrow and legend (sometimes called a key) to describe clearly all the elements depicted in the map (Figure 2). If you are presenting three-dimensional perspective images, you should indicate the distance along at least one of the horizontal dimensions to give an indication of scale, and also show a North Arrow (Figure 3). Figure 1 Components of a regional location map. Figure 2 Components of a study area description map. Figure 3 Components of a three-dimensional perspective map. These examples are from my own published work. I created all of them initially using ESRI’s ArcGIS software, which I used to do the basic cartography. I then exported the raw images to a drawing package for line work and text (I used CorelDraw, but any other graphics/drawing package would suffice such as Adobe Illustrator). This was because I found the drawing and text capabilities of ArcGIS to be less satisfactory than the specially designed graphics package. I used Sigmaplot for most of my graphing work. Similar to my maps, I used the graphing software to produce the basic graph format (axis ticks and the plotted data themselves), and then exported the result to a drawing package, where I had most control over formatting lines, points and text. It was also easy to import other kinds of graphs from different software packages. Figure 4 is an example of a diagram where the axes and stratigraphic data were originally plotted in Sigmaplot, the two plant fossil graphs were produced originally in specific paleoecological data software (Tilia Graph), and both kinds were imported into CorelDraw to complete line work, shading and text. Figure 4 Example of a combined diagram and graphs, using outputs from Sigmaplot and Tilia Graph that were imported into CorelDraw in which line work, shading and text were then completed. In designing the layout of both maps and figures, I always size images according to the end use. For example, in my postgraduate theses I always sized the document to A4 size, taking into account margin widths. For journal submissions, I look at the Guide for Authors to determine the required image size (width), and if there is no image size information I literally measure with a ruler the typical full-size images in a published article, and use these dimensions. Having established my image size, I make the most of the space I have. I always print out the images to see if the labels and other text are legible at the intended size or final production. Usually journals will recommend or specify font types and sizes, and you should follow these instructions. The above process can be time consuming, but is absolutely essential for two reasons: 1) to meet a journal’s requirements; and 2) to make it easier for you to write about your results. The more time you spend on perfecting your display items, the more you have thought about them. This should enable you to describe their main features in a clear, concise way so that the reader can easily and quickly see what you are writing about. Although Napoleon Bonaparte said “a picture is worth a thousand words”, it is probably difficult to quantify exactly how many words your display items are worth. However, based on my own experience the creation of clear maps and graphs is invaluable in making your own thinking clear about what your results are and how you should summarize them concisely in your results section. Happy mapping and graphing! Matthew Hughes, PhD Soil Sciences Editor, Edanz Group China
A man-made desert is not fantastic as it sounds. Two major factors are believed to account for the growth of man-made deserts. One is that the borders of desert in arid or semi-arid regions are extended far beyond the natural true desert into more humid climates due to the heavy grazing and cultivation by man. The other one is that the operation of mankind’s exploitative and destructive activities has brought enormous wastage of soil resources with rapid sloping runoff. The great enemy of the human race is soil erosion, which has been associated with the habitations of man since before the dawn of history. The histories of human civilizations tell us that buried civilizations is man-made, more than climatic change. According to archaeologists the Sahara, the Central Asian deserts, arid parts of Palestine, Mesopotamia and the Gobi and North China were once prosperous with human life. As background factors, climatic changes and geologic erosion are long processes affecting human habitations, compared to the history of human society. Comparatively, accelerated erosion, in which soils are washed away far in excess of possible soil formation, can make a mass of loss of soil resources within short time. The accelerated erosion is direct result of destroying the protective vegetation covering of soils. The fertile topsoil is rapidly washed away, or blown off, and then the land productivity reduces until cultivation is abandoned. The decadence of civilizations of North China and Mayan has been attributed to man-induced soil erosion and its consequences in increased run-off. It is evident that man-made deserts have occurred in the past and are still in progress. We Americans boast of a modern civilization and its progress, but we have been following suicidal methods in treatment of soil resources. Climate does change, but not an the comparatively rapid rate of the decadence of vast areas of habitable regions. Fortunately ， experimental studies have given a better understanding of how deserts may be man-made. And we may put into effect measures adequate to the conservation of soil resources and its productivity and its sustainable utilization.
The Dust Bowl from the Great Plains happened on May 11, 1934, covering half the nation with a thin layer of grit. This was an expensive lesson in the ecological history of the United States. From both economic and ecological viewpoints, most of the Great Plains is better suited to grazing than to farming. Yet several times over the last century, prolonged periods of good rainfall have encouraged a counterfeit optimism about the capacities of the Plains among newcomers, and even among many long-time residents. Humans have repeatedly extended their farms and expended their cattle herds beyond safe levels during the wet years, to be brought rudely back to reality when the drought cycle returned. The Dust Bowl of the thirties catalyzed a main turn on soil conservation practices in America. After the unprecedented dust storms soon followed by the formation, in 1935, of a Soil Conservation Service, federal promotion of soil conservation practices in the Great Plains. From then on, the soil erosion research and soil conservation practices had been improved little by little. However, forces from free market were promoting a recession of soil conservation, which is a challenge for the government and soil conservation workers. Similarly, the ecological lessons were learned by the Soviet Union. During 1960s ， the virgin lands, in western Siberia, and eastern Russia, once became the another American Dust Bowl because of misleading on politics and chasing for high grain production. In sum, the two costly lessons, the Dust Bowl and the Virgin Lands, are the great important events on the development of the world soil conservation.
浏览了一下，最新一期的 IEEE Transactions on Geoscience and Remote Sensing上报道了两篇与 全球尺度环境遥感产品有关的科学成果。其中，有一篇是对SMOS的产品改进。 看了摘要信息，觉得他们的工作思路和研究成果对我个人来说都是有益的。 1， Toward SMOS L4 SSS Products: Improving L3 SSS With Auxiliary SSS Data 2，WindSat Global Soil Moisture Retrieval and Validation
Soil texture is a soil property used to describe the relative proportion of different grain sizes of mineral particles in a soil. Particles are grouped according to their size into what are called soil separates. These separates are typically named clay , silt , and sand . Soil texture classification is based on the fractions of soil separates present Soil separates in a soil. The soil texture triangle is a diagram often used to figure out soil textures. Soil separates Soil separates are specific ranges of particle sizes. In the United States, the smallest particles are clay particles and are classified by the USDA as having diameters of less than 0.002mm. The next smallest particles are silt particles and have diameters between 0.002mm and 0.05mm. The largest particles are sand particles and are larger than 0.05mm in diameter. Furthermore, large sand particles can be described as coarse , intermediate as medium , and the smaller as fine . Other countries have their own particle size classifications. USD classification Name of soil separate Diameter limits (mm) Clay less than 0.002 Silt 0.0020.05 Very fine sand 0.050.10 Fine sand 0.100.25 Medium sand 0.250.50 Coarse sand 0.501.00 Very coarse sand 1.002.00 Soil texture classification Soil textures are classified by the fractions of each soil separate (sand, silt, and clay) present in a soil. Classifications are typically named for the primary constituent particle size or a combination of the most abundant particles sizes, e.g. sandy clay or silty clay. A fourth term, loam , is used to describe a roughly equal concentration of sand, silt, and clay, and lends to the naming of even more classifications, e.g. clay loam or silt loam. In the United States, twelve soil texture classifications are defined by the USDA: Clay ( 粘土 ) Silt （ 粉土 ） Sand （ 砂土 ） Loam （ 壤土 ） Silty clay Sandy clay Clay loam Silt loam Sandy Loam Loamy sand Silty clay loam Sandy clay loam Determining the soil textures is often aided with the use of a soil texture triangle. Soil texture triangle, showing the 12 major textural classes, and particle size scales as defined by the USDA. History of classification The first classification, the International system, was first proposed by Atterberg (1905), and was based on his studies in southern Sweden. Atterberg chose 20 m for the upper limit of silt fraction because particles smaller than that size were not visible to the naked eye, the suspension could be coagulated by salts, capillary rise within 24 hours was most rapid in this fraction, and the pores between compacted particles were so small as to prevent the entry of root hairs. Commission One of the International Society of Soil Science (ISSS) recommended its use at the first International Congress of Soil Science in Washington in 1927. Australia adopted this system and according to Marshall (1947) its equal logarithmic intervals are an attractive feature worth maintaining. The USDA adopted its own system in 1938, and the FAO used the USDA system in the FAO-UNESCO world soil map and recommended its use. References Soil Texture , by R. B. Brown, University of Florida, Institute of Food and Agricultural Sciences. Atterberg A (1905) Die rationalle Klassifikation der Sande und Kiese. Chemiker Zeitung 29, 195-198. Davis ROE, Bennett HH (1927) Grouping of soils on the basis of mechanical analysis. United States Department of Agriculture Departmental Circulation No. 419. Marshall TJ (1947) Mechanical composition of soil in relation to field descriptions of texture. Council for Scientific and Industrial Research, Bulletin No. 224, Melbourne. Prescott JA, Taylor JK, Marshall TJ (1934) The relationship between the mechanical composition of the soil and the estimate of texture in the field. Transactions of the First Commission of the International Society of Soil Science 1, 143-153. Toogood JA (1958) A simplified textural classification diagram. Canadian Journal of Soil Science 38, 54-55. Whitney M (1911) The use of soils east of the Great Plains region. United States Department of Agriculture Bureau of Soils Bulletin No. 78. Retrieved from http://en.wikipedia.org/wiki/Soil_texture A question is that although we know the diameter limit of sand, silt and clay according to the USDA classification, why we use to separate them by the pipette method ( Sheldrick and Wang, 1993 ) instead of by dry-sieving. Thinking If sand were determined by dry-sieving, Beside real sand, itcontens the macroaggregates. Therefore, we can obtain soil aggregates by dry sieving. In fact, the USDA tell us its diameter limits, which does not mean that anything within the range of sand diameter is sand.
1.medium for plant growth; 2.foundation for building and civil structure; 3.raw material for industry; 4.sequestering carbon to mitigate climate change; 5.denaturing and filtering pollutants; 6.disposing of industrial and urban wastes; 7.being an archiv of human and planetary history; 8.being repository of germplasm and biodiversity; 9.maintaining and strengthing cycle of water and elements and moderating impacts of natural and anthropogenic perturbations on the environment; 10.maintaining aesthetic and cultural and artistic values of landscape and ecosystem and preserving cultural heritage.
以前也碰到过某个地区森林和土壤养分含量偏高的情况，数据不充分，难以解释，不妨看看别人怎么解释的． Title: High Foliar and Soil Nitrogen Concentrations in Central Appalachian Forests Authors: Davis, SC; Dragan, KE; Buyarski, CR; Thomas, RB Source: ECOSYSTEMS 12 (1): 46-56 FEB 2009 Language: Author Keywords: soil nitrogen; foliar N; Central Appalachian; West Virginia; hardwood species; spatial variation; ecosystem scaling; canopy N; eastern US hardwood forests; topography; Fernow Experimental Forest Abstract: Regional topography and climate variation yield differences in ecosystem attributes that make spatially scaled estimates of forest productivity challenging. Foliar nitrogen is a primary indicator of forest ecosystem productivity and is used in regional estimates of terrestrial productivity, but this characteristic has not been well described in the Central Appalachian region. Here we describe foliar and soil N variation among species and elevations at two spatial scales in the Central Appalachian region: (1) across the Elklick watershed in the Fernow Experimental Forest and (2) across the state of West Virginia. We found higher foliar N concentrations at both scales than those previously reported for other temperate forest regions . Canopy and soil nitrogen concentrations were also much greater in the Fernow than generally observed across West Virginia. Soil N concentrations in the Fernow were two times greater than those observed across West Virginia. Species-related differences were observed at both spatial scales, but were not always consistent. Canopy N ranges are generally consistent across elevations throughout the state of West Virginia, but should be scaled according to species-related elevation effects for studies that estimate productivity differences in response to harvest or changing species composition. The incongruence of foliar and soil N concentrations at the Fernow Experimental Forest are not explained by elevation or species composition, but are likely a consequence of greater historical N and H+ deposition relative to the surrounding West Virginia region. weblink: http://gateway.isiknowledge.com/gateway/Gateway.cgi?GWVersion=2SrcAuth=AlertingSrcApp=AlertingDestApp=WOSDestLinkType=FullRecord;KeyUT=000263794200004
标签: soil
