The measurement of the variation with depth of the hydraulic conductivity of saturated soil monoliths

Hydraulic conductivity profiles of saturated composite porous columns were obtained in two ways: first, from measurements of the hydraulic potential profiles with uniform vertical flow; and second, by making use of a potential theorem concerning the flow between sources and sinks, from measurements of the hydraulic potential difference between the ponded surface and the base when the flow was intercepted in turn by successive drains located at intervals down the column. Both techniques gave the same results. The hydraulic conductivity profile of a structurally unstable column changed significantly with time, suggesting that such measurements might be used to monitor soil structural changes and root development in lysimeter studies.     

Biogeochemical interfaces in soil: The interdisciplinary challenge for soil science

Soil, the “Earth's thin skin” serves as the delicate interface between the biosphere, hydrosphere, atmosphere, and lithosphere. It is a dynamic and hierarchically organized system of various organic and inorganic constituents and organisms, the spatial structure of which defines a large, complex, and heterogeneous interface. Biogeochemical processes at soil interfaces are fundamental for the overall soil development, and they are the primary driving force for key ecosystem functions such as plant productivity and water quality. Ultimately, these processes control the fate and transport of contaminants and nutrients into the vadose zone and as such their biogeochemical cycling. The definite objective in biogeochemical‐interface research is to gain a mechanistic understanding of the architecture of these biogeochemical interfaces in soils and of the complex interplay and interdependencies of the physical, chemical, and biological processes acting at and within these dynamic interfaces in soil. The major challenges are (1) to identify the factors controlling the architecture of biogeochemical interfaces, (2) to link the processes operative at the individual molecular and/or organism scale to the phenomena active at the aggregate scale in a mechanistic way, and (3) to explain the behavior of organic chemicals in soil within a general mechanistic framework. To put this in action, integration of soil physical, chemical, and biological disciplines is mandatory. Indispensably, it requires the adaption and development of characterization and probing techniques adapted from the neighboring fields of molecular biology, analytical and computational chemistry as well as materials and nano‐sciences. To shape this field of fundamental soil research, the German Research Foundation (DFG) has granted the Priority Program “Biogeochemical Interfaces in Soil”, in which 22 individual research projects are involved.     

The preparation of soil thin sections for biological studies

A method is described that permits the preparation of soil thin sections up to 6 × 8 cm in approximately 14 days without any discernable artefact. Soil samples are fixed in buffered glutaraldehyde, dehydrated rapidly in a graded series of acetone: water mixtures and impregnated with a polyester resin. The method effectively preserves biological material, such as delicate protozoan cells and root tissues. A range of stains were tested for staining roots in soil blocks and in soil thin sections.     

The changing scene of British soil science1

The development of soil science has, in the past, been largely driven by the need to improve agricultural production. It is an applied science. Soils and soil processes have had a profound impact on the development of agriculture, and civilization, throughout the ages. Mistreatment of soil has, over the millennia to the present day, been responsible for horrific human tragedy. The most pressing challenge to soil science is to devise ways of improving food production, at minimum cost, in those areas of the world where food shortages are most acute. The new era of reducing price support for major agricultural commodities will increase competition in the EC and elsewhere. It will become imperative to improve efficiency of crop production, especially by the introduction of novel techniques, if arable and horticultural cropping in the UK is to flourish. Soil science is becoming increasingly important in assisting governments to develop policies and in assisting commercial organizations to screen and introduce new chemicals. There is a wide range of environmental and pollution problems that demand inputs from soil science. They include industrial degradation of soil, entry of toxic materials into the food chain, waste disposal, industrial contamination of the atmosphere and the sub-sequent effects on soil and vegetation, forest decline, and the improvement of industrially damaged areas to attract new industries and reduce unemployment. Far greater use should be made of soils information in urban and rural planning and in building design as, at least in some countries, this practice has resulted in considerable financial savings. Advances in theory, measurement and computing are revolutionizing soil science and will greatly facilitate the application of the subject to practical problems.     

The frontier of soil science: Soil health

<正>Soils are a valuable resource with life activity in terrestrial ecosystem, and soil health and its sustainable management are becoming a major focus of global concern. A healthy soil is a “harmonious social system”, which should have good structure, functional state,and buffering performance to maintain the dynamic balance of soil ecosystem. Soil health has become the frontier of soil science. The development of theoretical and practical approaches for soil health evaluation and managem...     

The mission of soil science in a changing world

The soil is a vital, complex, and labile medium. To manage it effectively and sustainably, we must strive to understand its attributes, functions, and environmental interactions. Toward this holistic end, we need to overcome traditional disciplinary and institutional barriers so as to promote interdisciplinary cooperation among teams of scientists with different but mutually complementary specialties. Herein, we provide an historical and cultural review of the evolving relationship between humanity and the soil.     

土地质量评估与监测: 土壤科学面临的新挑战

Sustainable land management (SLM)is the key to harmonizing environmetal and ecolgical concerns of society with the economic realities of producing adequate food and fiber of high quality and ensuring a absi minimal quality of life.The aim of SLM is to maintain the integrity of the biophysical land resource base,but it can only be realized if land users understand the impacts of land management options on their lands but also on other off-site areas and can optimize the socioeconomic and environmetal benefits of their choice.To Facilitate this,the Contribution of soil suvery organizations would be through the assessment and monitoring of land quality.Land quality is a measure of the ability of land to perfor specific functions and is derived by an integration of soil survey information with other environmental,and if necessary,socioeconomic information.The desired reliability influences the operational scale of the assessment,Such an assessment would assist in:1) locating homologous areas for research sites or for transferring technologies;2) providing the geographic basis for systems analysis(e.g.modeling);3) serving as a basis for local,natinal and global resource assessment and monitoring;4) providing an ecosystem context for land use,assessments of temporal and spatial variability,and impact of human interventions;5)serving as a framework for more detailed assessment for all levels of interest;and 6) evaluating global issues such as food security,impacts of climate change,biodiversity montoring,and addressing desertification.Based on an evaluation of the progress made in soil resource inventories and considering the demands of the environment focused world,the paper considers the need for counteries to mount such a program.The authors believe that this is the next demand of soil science and that we can fulfill our soical contract by periodically providing such information on the state of a nation‘s land resource.     

Roots,rhizosphere and soil: the route to a better understanding of soil science?

The centenary of Hiltner's recognition of a rhizosphere effect is a convenient point to assess the impact of such thinking on the direction of soil science. A review of the major soil journals suggests that for much of the last century, Hiltner's insight had little effect on mainstream thinking outside of soil microbiology, but this situation is changing rapidly as the consequences of spatial and temporal heterogeneity on soil functioning assumes greater importance. Studies of root growth, root distributions and of rhizosphere processes over the last 25 years demonstrate both the size and distribution of root systems and the associated inputs from roots to soils. These inputs result in a plethora of dynamic reactions at the root–soil interface whose consequences are felt at a range of temporal and spatial scales. Root growth and respiration, rhizodeposition, and uptake of water and nutrients result in biological, chemical and physical changes in soils over variable distances from the root surface so that the rhizosphere has different dimensions depending on the process considered. At the root length densities common for many crop species, much of the upper 0.1 m of soil might be influenced by root activity for mobile nutrients, water and root‐emitted volatile compounds for a substantial proportion of the growing season. This brief review concludes that roots are an essential component of soil biology and of soil science.     

Early soil knowledge and the birth and development of soil science

Soils knowledge dates to the earliest known practice of agriculture about 11,000 BP. Civilizations all around the world showed various levels of soil knowledge by the 4th century AD, including irrigation, the use of terraces to control erosion, various ways of improving soil fertility, and ways to create productive artificial soils. Early soils knowledge was largely based on observations of nature; experiments to test theories were not conducted. Many famous scientists, for example, Francis Bacon, Robert Boyle, Charles Darwin, and Leonardo da Vinci worked on soils issues. Soil science did not become a true science, however, until the 19th century with the development of genetic soil science, led by Vasilii V. Dokuchaev. In the 20th century, soil science moved beyond its agricultural roots and soil information is now used in residential development, the planning of highways, building foundations, septic systems, wildlife management, environmental management, and many other applications in addition to agriculture.     

Comparison of soil preparation methods for rice production in the Middle Nile Delta,Egypt

Field experiments were conducted during the summer seasons of 2011 and 2012 in the Middle Delta of Egypt to compare alterations in saving water and grain yield of transplanted rice in clay loam soil after compaction, wet tillage (puddling) and dry tillage (non-puddling). The results indicate that compacted soil gave higher grain yield, higher irrigation water productivity, higher net income, higher benefit–cost ratio, and less water consumption than wet and dry tillage. The results suggest that soil compaction by four passes of steel plank (2 m long and 600 kg weight) before planting rice is beneficial in terms of saving water and net return. In addition, it can be used instead of the non-puddling method under the conditions of the studied area. Therefore, soil compaction can be considered as a pioneering method of pre-planting soil preparation to increase rice yield and to save irrigation water. It is highly recommended to be used by farmers.     

The role of soil science in the land use negotiation process*

Abstract. The hierarchial concept of land use planning becomes less relevant in a society with continuous interactions between stakeholders, researchers, planners and politicians. In this context, land use negotiation rather than land use planning appears to be the most appropriate concept. In the negotiation process, good quality data about the land is important as land properties are, obviously, key elements to be considered. Case studies at farm and regional level have been analysed to explore answers to a number of questions. How can soil data be presented most effectively? What are the research needs? How can the large existing body of data be mobilized most effectively? Studies on regional land use in Costa Rica used methods in a logical sequence including projections, explorations and predictions of land use patterns. The work involved upscaling of data, obtained at farm level, to the regional level. Work at farm level focussed on prototyping procedures in which farming systems were ‘designed’ by close interaction between farmers and scientists, including applications of precision agriculture. Soil data demands were analysed, emphasizing the effects of using data with different degrees of detail together with the application of pedotransfer functions which effectively transform existing data into parameters that are difficult or expensive to measure directly. This not only facilitated interactions with stakeholders but also with colleague scientists in interdisciplinary teams. In addition, use of Geographical Information Systems allowed visual presentations of alternative geographical land use patterns that were associated with various scenarios, thereby facilitating the interaction processes. A plea is made to increase interaction of stakeholders and researchers by considering research programmes as vehicles for joint learning.     

The preparation of unsmeared soil surfaces and an improved apparatus for infiltration measurements

A method is described for using a quick setting epoxy resin to prepare a soil surface for infiltration measurements. It gives an unsmeared soil surface where the biological pores and structural surfaces are revealed. Experiments with an alluvial Prairie Soil and a Red Podzolic Soil, comparing steady state infiltration rates through cut smeared surfaces and resin treated ones, showed that the resin-prepared surface permits 2.5–6 times more rapid entry of water. It is postulated that the greater rate more closely reflects the field structural condition. Apparatus, with a water reservoir remote from the hole, is also described for measuring constant head subsoil infiltration through a specially prepared auger hole.     

The challenge for the soil science community to contribute to the implementation of the UN Sustainable Development Goals

Seventeen Sustainable Development Goals (SDGs) were adopted by 193 Governments at the General Assembly of the United Nations in 2015 for achievement by 2030. These SDGs present a roadmap to a sustainable future and a challenge to the science community. To guide activities and check progress, targets and indicators have been and are still being defined. The soil science community has published documents that describe the primary importance of soil for SDGs addressing hunger, water quality, climate mitigation and biodiversity preservation, and secondary relevance of soil for addressing several other SDGs. Soil scientists only marginally participated in the SDG discussions and are currently only peripherally engaged in discussions on targets or indicators. Agreement on several soil‐related indicators has still not been achieved. Involvement of soil scientists in SDG‐based studies is desirable for both developing solutions and increasing the visibility of the soil profession. Inputs into policy decisions should be improved as SDG committee members are appointed by Governments. Possible contributions of soil science in defining indicators for the SDGs are explored in this paper. We advocate the pragmatic use of soil–water–atmosphere–plant simulation models and available soil surveys and soil databases where “representative” soil profiles for mapping units (genetically defined genoforms) are functionally expressed in terms of several phenoforms reflecting effects of different types of soil use and management that strongly affect functionality.     

The effect of preplanting soil preparation and soil management on soil physical parameters in an apple orchard

Abstract. Effects on soil physical properties in a trial which compared establishing an apple orchard on grassed and cultivated soil and of maintaining soil with or without a vegetative cover post-planting are discussed. On a fine sandy loam soil (Fyfield series) prone to erosion, bulk density, water filled porosity and soil erosion, measured at intervals after the establishment year, were all unaffected by the use of grass. Infiltration rate was much higher on grassed than on herbicide treated soil as was the apparent ability to accept heavy rainfall.     

Some aspects of the history of German soil science

During the 19^th century, soil science in Germany developed from a combination of agriculture and both geology and forestry. Further research developments described in this review include pedology, soil classification and mapping, soil chemistry and mineralogy, soil physics, and ecosystem research. Beside this, the German Society of Soil Science and their relations to the International Society (Union) of Soil Science are shortly introduced.