目錄

• 源數據庫
• 數據庫內容
• 土壤制圖單位標識符
• 土壤單位命名
• 土壤階段
• 土壤性質
• 最后

源數據庫

使用了四個源數據庫來編譯HWSD的1.0版：歐洲土壤數據庫（ESDB），中國的百萬土壤圖，各種區域SOTER數據庫（SOTWIS數據庫）和世界土壤圖。

數據庫內容

HWSD由鏈接到Microsoft Access格式中的屬性數據庫的GIS柵格圖像文件組成。盡管這些組件是單獨的數據文件，但是可以通過商業GIS系統鏈接它們。數據庫隨附的查看器會自動創建此鏈接，并提供對兩個數據源的直接訪問。

HWSD屬性數據庫為15773個土壤測繪單位中的每一個提供有關土壤單位組成的信息。該數據庫顯示了每個土壤測繪單元的組成，以及表層和下層土壤的標準化土壤參數。一個土壤測繪單元在數據庫中最多可以有9個土壤單元/表土質地組合記錄。

用于標識土壤測繪單元的核心字段包括：
MU GLOBAL----HWSD的統一土壤測繪單元標識符，提供到GIS層的鏈接；
MU SOURCEI和MU SOURCE2----源數據庫中的映射單元標識符；
SEQ----土壤單元在土壤測繪單元組成中的順序；
SHARE----在制圖單位中的土壤單位/表層土壤紋理組合的份額-00：以及使用FAO-74分類系統或FAO-90分類系統（SU SYM74或SU SYM90）或FAO-85臨時系統的土壤單位符號（SU SYM85）。

數據共有三個數據塊：
關于土壤測繪單元組成的一般信息；
與階段有關的信息；
表土（0-30厘米）和下層土壤（30-100厘米）的理化特性。

土壤制圖單位標識符

ID (Identifier)

Internal unique indexed database identifier (4-byte integer) 內部唯一索引數據庫標識符（4字節整數）

MU_GLOBAL (Global Mapping Unit Identifier)

The Global Mapping Unit identifier (4-byte integer) provides the link between the GIS layer and the attribute database.
全局映射單元標識符（4字節整數）提供GIS層與屬性數據庫之間的鏈接。

MU_SOURCE1 (Source Database Mapping Unit Identifier)

This alphanumerical field stores the main mapping unit identifier from the source database, as shown below:
此字母數字字段存儲源數據庫中的主要映射單元標識符，如下所示：

MU_SOURCE2 (Source Database Mapping Unit Identifier)
This second (4-byte numerical) identifier may be used to accommodate a second unit identifier in the source database; it has been populated
with the STU from ESDB only.
此第二個（4字節數字）標識符可用于在源數據庫中容納第二個單元標識符；僅使用來自ESDB的STU進行填充。

COVERAGE (Source database)
This field stores the source of the record. 該字段存儲記錄的來源。
值0用于當前未被任何土壤數據庫（主要是非常小的島嶼）覆蓋的土地單位。

ISSOIL (Flag for non-soil units)
Field indicating if the soil mapping unit is a soil or a non-soil. 表示土壤測繪單位是土壤還是非土壤的字段。

SEQ (Sequence within the mapping unit)
The sequence in which soil units within the soil mapping unit are presented follow the rule that the dominant soil always has sequence1. The sequence can range between 1 and 9.
在土壤測繪單元中顯示土壤單元的順序遵循以下規則：優勢土壤始終具有順序1。該順序的范圍可以是1到9。

SHARE (Share of the soil unit)
Share of the soil unit within the mapping unit in %. Shares of component soil units5 of a mapping unit always sum up to 100%.
土壤單位在制圖單位中所占的百分比。 映射單元的組成土壤單元5的份額總和為100％。

土壤單位命名

SU_SYMBOL
> This symbol stands for the spatially dominant major soil group.
It is used here for thematic mapping purposes to show the ‘main’ HWSD soil groups in the viewer.
FAO-74 soil units have been correlated with FAO-90 units in order to have a unique coding system for the main soil unit for each mapping unit in the database;
the soil unit codes are given in Annex 2.
該符號代表在空間上占優勢的主要土壤群。
此處用于主題映射，以在查看器中顯示“主要” HWSD土壤組。
FAO-74的土壤單位與FAO-90的單位相關聯，以便為數據庫中每個測繪單位的主要土壤單位建立一個獨特的編碼系統；
土壤單位代碼見附件2。

SU_SYM74
> This is the soil unit symbol according to the FAO-74 soil classification, as used for the DSMW coverage; see annex 2 and for further details, http://www.fao.org/landandwater/agll/key2soil.stm and the legend of the Soil Map of the World (FAO/Unesco, 1974)
這是根據FAO-74土壤分類的土壤單位符號，用于DSMW覆蓋范圍；見附件2，更多細節，http://www.fao.org/landandwater/agll/key2soil.stm和《世界土壤圖例》（糧農組織/聯合國教科文組織，1974年）

SU_SYM85
This is the soil unit symbol according to the FAO-85 interim
soil classification which is used for the ESDB coverage; see
http://eusoils.jrc.it/ESDB_Archive/ESDBv3/legend/LegendData.cfm This system was intermediate between the FAO-74 Legend (see above) and the FAO-90 Revised Legend (see below). The parts of the ESDB where correlations with FAO 90 are lacking, the SU-SYM85 has tentatively been correlated to SU_SYM90.

根據FAO-85臨時規定，這是土壤單位的符號，用于ESDB覆蓋的土壤分類；
http://eusoils.jrc.it/ESDB_Archive/ESDBv3/legend/LegendData.cfm該系統位于FAO-74圖例（見上文）和FAO-90修訂圖例（見下文）之間。 ESDB中缺少與FAO 90相關的部分，SU-SYM85暫時與SU_SYM90相關。

SU_SYM90
This is the soil unit symbol according to the FAO-90 soil
classification, which was used here for the ESDB, China and SOTWIS coverage; see Annex 2 and for further details the Revised Legend of the FAO/Unesco Soil Map of the World in FAO World Soil Resources Report 60 (FAO/Unesco/ISRIC, 1990)
這是根據FAO-90土壤的土壤單??位符號分類，在此用于ESDB，中國和SOTWIS的覆蓋范圍；見附件2，更詳細的資料見《糧農組織世界土壤資源報告60》中的《糧農組織/聯合國教科文組織世界土壤圖訂正本》（糧農組織/聯合國教科文組織/ ISRIC，1990年）。

SU_CODE
The numerical code for the major soil group (FAO-90), used for
the HWSD.
主要土壤群的數字代碼（FAO-90），用于HWSD。

SU_CODE74
The numerical code for the FAO-74 soil classification system.
FAO-74土壤分類系統的數字代碼。

SU_CODE85
The numerical code for the FAO-85 soil classification system.
FAO-85土壤分類系統的數字代碼。

SU_CODE90
The numerical code for the FAO-90 soil classification system.
FAO-90土壤分類系統的數字代碼。

T_TEXTURE (Topsoil texture class)
Topsoil textural class refers to the simplified textural classes for 0–30cm used in the Soil Map of the World (FAO/Unesco, 1970-1980). Because of the scale of the map (1:5 million) only three simplified textural classes were used. Coarse textured: sands, loamy sands and sandy loams with less than 18 percent clay and more than 65 percent sand. Medium textured: sandy loams, loams, sandy clay loams, silt loams, silt,silty clay loams and clay loams with less than 35 % clay and less than 65 % sand; the sand fraction may be as high as 82 percent if a minimum of 18 percent of clay is present. Fine textured: clays,sandy clays, clay loams and silty clay loams with more than 35 percent clay.
表土質地類別是指《世界土壤地圖》中使用的0–30cm的簡化質地類別（糧農組織/教科文組織，1970-1980年）。
由于地圖的比例（1：5百萬），僅使用了三個簡化的紋理類。
粗糙的紋理：具有少于18％的粘土和超過65％的沙子的砂，壤質砂和壤質壤土。
中等質地：沙質壤土，壤土，沙質壤土，粉質壤土，粉砂，粉質粘土質壤土和黏土含量小于35％，砂度小于65％的粘土質壤土；
如果至少有18％的粘土存在，則砂的含量可能高達82％。
精細紋理：黏土，含黏土超過35％的沙質黏土，壤土壤土和粉質黏土壤土。含黏土超過35％的沙質黏土，壤土壤土和粉質黏土壤土。

REF_DEPTH
Reference depth of the soil unit. Reference soil depth of all soil units are set at 100 cm, except for Rendzinas and Rankers of FAO-74 and Leptosols of FAO-90, where the reference soil depth is set at 30 cm, and for Lithosols of FAO-74 and Lithic Leptosols of FAO-90, where it is set at 10 cm6. An approximation of actual soil depth can be derived through accounting for relevant depth limiting soil phases, obstacles to roots and occurrence of impermeable layers (the latter two refer to ESDB only).
土壤單位的參考深度。
除Rendzinas和FAO-74的等級和FAO-90的細小溶膠（將參考土壤深度設置為30 cm）以及FAO-74的石棉和石質細小溶膠之外，所有土壤單位的參考土層深度均設置為100 cm
設置在10平方厘米處的90號糧農組織標準。
通過考慮相關的深度限制土壤相，根系障礙和不透水層的出現，可以得出實際土壤深度的近似值（后兩個僅指ESDB）。

AWC
Available water storage capacity in mm/m of the soil unit For the soil units of the Soil Map of the World (FAO-74) and for the revised legend (FAO-90), FAO has developed procedures for the estimation of Available Water Capacity in mm/m (AWC) (FAO, 1995). The AWC classes have been estimated for all soil units of both FAO classifications accounting for topsoil textural class and depth/volume limiting soil phases.
以毫米/米為單位的土壤單位的可用儲水量
對于《世界土壤圖》（FAO-74）和經修訂的圖例（FAO-90）的土壤單位，糧農組織制定了估算可用水量的程序
容積，單位mm / m（AWC）（糧農組織，1995年）。
估計了糧農組織所有分類中所有土壤單位的AWC分類，其中包括了表層土壤質地分類和限制土壤深度/體積的階段。
The following AWC classes are used

土壤階段

階段1 –階段2（PHASE1 – PHASE2）
階段是根據特征對土壤單元進行細分，這些特征對于土地的使用或管理很重要，但不能診斷出土壤單元本身的分離。
世界土壤圖（FAO-74）中使用了第1至12期，世界土壤圖的修訂圖例（FAO-90）中使用了第13至22期，而第23至30期是針對歐洲土壤數據庫的。

根（障礙物的根）：提供STU中根的障礙物的深度等級。
ROOTS (Obstacle to Roots): Provides the depth class of an obstacle to roots within the STU.

IL（防滲層）：指示STU的土壤剖面中存在防滲層。
該代碼僅在ESDB中可用。
IL (Impermeable Layer): Indicates the presence of an impermeable layer within the soil profile of the STU. The code is only available in ESDB.

SWR（土壤水分狀況）：指示STU的土壤剖面中占主導地位的年度平均土壤水分狀況類別。
該代碼僅在ESDB中可用。
SWR (Soil Water regime): Indicates the dominant annual average soil water regime class of the soil profile of the STU. The code is only available in ESDB.

土壤性質

Derived chemical and physical soil properties are provided for topsoil (0-30cm) and subsoil (30-100 cm) separately.
分別提供了表層土壤（0-30cm）和下層土壤（30-100 cm）的化學和物理土壤性質。

ADD_PROP (Additional Property)
Certain soil properties, inherent to the soil unit definition that are relevant for agricultural use of the soil are vertic7, gelic8 and petric9; the latter property refers to petric Calcisols and petric Gypsisols (FAO-90). The additional field provides details on Petric, Gelic Vertic properties.
ADD_PROP（附加屬性）
土壤單位定義所固有的與土壤農業用途相關的某些土壤性質是頂點，7、8和9。后一特性是指石油鈣化溶膠和石油石膏酸（FAO-90）。附加字段提供有關Petric，Gelic Vertic屬性的詳細信息。

T_GRAVEL and S_GRAVEL
Volume percentage gravel respectively in the top- and subsoil Gravel stands for the percentage of materials in a soil that are larger than 2 mm.
礫石在上層土壤和下層土壤中的體積百分比分別表示大于2毫米的土壤中物料的百分比。

T_SAND and S_SAND
Percentage sand in the in the top- and subsoil Sand comprises particles, or granules, ranging in diameter from 0.0625 mm (or 1?16 mm) to 2 millimeters. An individual particle in this range size is termed a sand grain. Sand feels gritty when rubbed between the fingers (silt, by comparison, feels like flour). Sand is commonly divided into five sub-categories based on size: very fine sand (1/16 - 1/8 mm diameter), fine sand (1/8 mm - 1/4 mm), medium sand (1/4 mm - 1/2 mm), coarse sand (1/2 mm - 1 mm), and very coarse sand (1 mm - 2 mm).
上層土壤和下層土壤中的百分比沙子包括直徑在0.0625毫米（或1?16毫米）至2毫米范圍內的顆粒或細粒。
在此范圍內的單個顆粒稱為沙粒。
當在手指之間摩擦時，沙子會感覺到堅硬（相比之下，淤泥的感覺就像面粉）。
沙子通常根據尺寸分為五個子類別：極細沙（1/16-1/8 mm直徑），細沙（1/8 mm-1/4 mm），中沙（1/4 mm- 1/2毫米），粗砂（1/2毫米-1毫米）和非常粗砂（1毫米-2毫米）。

T_SILT and S_SILT
Percentage silt respectively in the in the top- and subsoil Silt is produced by the mechanical weathering of rock, as opposed to the chemical weathering that results in clays. This mechanical weathering can be due to grinding by glaciers, eolian abrasion (sandblasting by the wind) as well as water erosion of rocks on the beds of rivers and streams. Silt is sometimes known as ‘rock flour’ or ‘stone dust’, especially when produced by glacial action. Mineralogically, silt is composed mainly of quartz and feldspar. Silt size is between 0.002 and 0.050 mm (USDA classification) and between 0.002 and 0.0625mm (ISO and FAO classification). In the database no difference is made between the two, but reported figures are used, whatever the source.
與巖石產生的化學風化作用相反，上層和下層土壤中的淤泥百分率是由巖石的機械風化作用產生的。
這種機械風化可能是由于冰川的打磨，風沙的磨蝕（風吹砂）以及河流和溪流床上的巖石的水蝕所致。
淤泥有時被稱為“巖粉”或“石粉”，尤其是在通過冰川作用產生時。
從礦物學上講，粉砂主要由石英和長石組成。
淤泥尺寸在0.002至0.050毫米之間（美國農業部分類）和0.002至0.0625毫米之間（ISO和FAO分類）。
在數據庫中，兩者之間沒有區別，但是無論來源如何，都使用報告的數字。

T_CLAY and S_CLAY
Percentage clay respectively in the in the top- and subsoil Clay is naturally occurring firm earthy material, composed primarily of fine-grained (diameter less than 0.002mm) that is plastic when wet and hardens when heated and that consists primarily of hydrated silicates or aluminum. Clay is mostly composed of clay minerals which are phyllo-silicate minerals and minerals which impart plasticity and harden when fired or dried. The definition of “fine-grained” used above is particles smaller than 2 μm, colloid chemists (and Eastern European soil scientists) may use 1 μm. In the database no difference is made between the two, but reported figures are used, whatever the source; these values are also used to determine the “USDA texture class” as given below].
上層土壤和下層土壤中的百分比粘土粘土是天然存在的堅硬的土質材料，主要由細粒（直徑小于0.002mm）組成，濕態時呈塑性，加熱時硬化，并且主要由水合硅酸鹽或鋁組成。
粘土主要由粘土礦物構成，這些礦物是葉狀硅酸鹽礦物，而礦物在煅燒或干燥后具有可塑性并變硬。
上面使用的“細顆粒”的定義是小于2μm的顆粒，膠體化學家（和東歐的土壤科學家）可能使用1μm。
在數據庫中，兩者之間沒有區別，但是無論來源如何，都使用報告的數字。這些值還用于確定“ USDA紋理類別”，如下所示。

T_USDA_TEX_ CLASS and S_USDA_TEX_CLASS
USDA texture class name and code. 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 (clay, silt, and sand). The soil texture class (e.g., sand, clay, loam, etc) corresponds to a particular range of separate fractions, and is diagrammatically represented by the soil texture triangle. Coarse textured soils contain a large proportion of sand, medium textures are dominated by silt, and fine textures by clay。
USDA紋理類名稱和代碼。
土壤質地是一種土壤特性，用于描述土壤中礦物質顆粒不同粒度的相對比例。 顆粒根據其大小分為所謂的土壤分離物（粘土，淤泥和沙子）。 土壤質地類別（例如，沙子，粘土，壤土等）對應于各個部分的特定范圍，并由土壤質地三角形示意性表示。 粗糙的粗糙土壤中含有大量的沙土，中等紋理以淤泥為主，精細紋理以黏土為主

T_REF_BULK_DENSITY and S_REF_BULK_DENSITY Reference Bulk Density of top- and subsoil. Reference bulk density is a property of particulate materials. It is the mass of many particles of the material divided by the volume they occupy. The volume includes the space between particles as well as the space inside the pores of individual particles.
表層和下層土壤的參考堆積密度。
參考堆積密度是顆粒材料的特性。
它是材料的許多顆粒的質量除以它們占據的體積。
該體積包括顆粒之間的空間以及單個顆粒的孔內部的空間。

T_OC and S_OC
This field gives the percentage of organic carbon in top- and subsoil. Organic Carbon is together with pH, the best simple indicator of the health status of the soil. Moderate to high amounts of organic carbon are associated with fertile soils with a good structure. Soils that are very poor in organic carbon (<0.2%), invariable need organic or inorganic fertilizer application to be productive. Soils with an organic matter content of less than 0.6% are considered poor in organic matter. The following classes are suggested to prepare maps of organic carbon status for mineral soils:
該字段給出了表層和下層土壤中有機碳的百分比。
有機碳與pH值一起，是土壤健康狀況的最佳簡單指示。
中度到高含量的有機碳與結構良好的肥沃土壤有關。
有機碳含量極低（<0.2％）的土壤始終需要施用有機或無機肥料才能生產。
有機質含量低于0.6％的土壤被認為有機質較差。
建議使用以下課程來準備礦物土壤的有機碳狀態圖：

最后

后面的內容大家就自己看吧，整理有點累😹

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