Mô tả và đánh giá đất hồ sơ Các chương trước bao gồm một loạt các đo đạc địa chất vật lý. Ngược lại, chương này giao dịch với chủ đề thường bị bỏ quên trong những phương pháp hình ảnh và xúc giác của đánh giá có thể được thực hiện trực tiếp trong lĩnh vực này. Cả hai đều có vị trí của mình. Hệ thống kiểm tra đất trong lĩnh vực này nên được một kỹ năng cơ bản để đánh giá trạng thái vật lý của nó. Đây là một trong những kết luận của hội nghị. | 15 Soil Profile Description and Evaluation Tom Batey University of Aberdeen Aberdeen Scotland I. INTRODUCTION The preceding chapters cover a wide range of soil physical measurements. In contrast this chapter deals with the often neglected topic of the visual and tactile methods of assessment that can be made directly in the field. Both have their place. Systematic examination of soil in the field should be a basic skill to evaluate its physical state. This was one of the conclusions of the international conference called Problems in Modern Soil Management van Ouwerkerk et al. 1992 . Information obtained in such a way can be used independently or can be used to complement and supplement measurements made by instruments in the field or the laboratory. Field examination should also precede the collection from the field of samples that are to be subject to other tests in the laboratory. A. General Background Expressions used to describe the field characteristics of soil go back to the beginnings of a settled agriculture. When manual work was required to till the soil and remove weeds differences in particle size were readily detected by contact with the foot and hand. Light and heavy expressions still in use did not refer to soil bulk density but to the stickiness of wet soil which is texture related. Despite the wide range of instruments available to measure physical properties of soils there are many circumstances where such tests cannot be done. The equipment may not be available the cost may be high and the time taken to complete a test may be so long that the results cannot be available in time to deal with a practical problem. Unless the soil is examined first samples taken for Copyright 2000 Marcel Dekker Inc. subsequent analysis may be taken from material that crosses physical boundaries and includes layers with dissimilar properties. There are also situations where the lateral distribution of a particular physical condition must be determined. Where any test .
