CN114971234B

CN114971234B - Soil general survey technical method

Info

Publication number: CN114971234B
Application number: CN202210512271.XA
Authority: CN
Inventors: 马小计; 王洪林; 赵京黔; 张璐; 马腾飞; 张海瑞; 邹春花; 郭超; 杨康; 郭亚宁
Original assignee: Beijing Sino Color Surveying And Mapping Institute Co ltd
Current assignee: Beijing Sino Color Surveying And Mapping Institute Co ltd
Priority date: 2022-05-11
Filing date: 2022-05-11
Publication date: 2023-04-07
Anticipated expiration: 2042-05-11
Also published as: CN114971234A

Abstract

The invention discloses a technical method for general survey of soil, which relates to the technical field of general survey of soil and comprises the following steps: s1, carrying out work preparation on the interior and the exterior of soil general survey, carrying out task decomposition and linkage according to actual field survey work flows of different counties and regions, and training the exterior survey; s2, designing an interior distribution scheme by combining natural and socioeconomic data to carry out field investigation, wherein the natural and socioeconomic data specifically comprise landform and landform, hydrogeology, meteorological data and the current situation of land utilization, and the method has the beneficial effects that: according to the tone and color contrast of the images of the aerial and satellite films in the investigation region, the soil interpretation marks and the typical images are contrasted, the pre-judgment sketch is drawn indoors, and the images are checked outdoors, so that the working efficiency and the investigation quality can be greatly improved, the general investigation efficiency is improved, and the soil general investigation technical method for the output of the standard general investigation result and the long-term utilization of the general investigation data is provided.

Description

Soil general survey technical method

Technical Field

The invention relates to the technical field of soil census, in particular to a technical method for soil census.

Background

The soil is a basic condition for clarifying cultivated land resources in China, the first soil general survey is developed in 1958-1960, the experience of farmers for identifying soil agricultural traits is summarized on the basis of the soil agricultural traits, and the first agricultural soil classification system in China is provided.

In 1979 of soil second general, china began to conduct second soil general survey historically, most areas basically complete general survey in the end of 1984 under unified organization and deployment of soil general survey offices, and a few areas continue to 1986, and the achievement summary work is completed in 1994. The second national land survey aims to comprehensively find the national land utilization condition, grasp real land basic data, carry out informatization and networked management on survey results, establish and perfect land survey, a statistical system and a registration system, realize the social service of land resource information and meet the requirements of economic and social development, land macroscopic regulation and control and national and local resource management.

The three general purposes of soil are that original data can not completely reflect the current quality of soil gradually due to rapid change of soil, a new general survey needs to be started urgently, gardens, grasslands, forest lands and the like are also changed dramatically in 40 years except for cultivated land, and the history from ecological damage to ecological restoration is experienced, and the three general purposes are also needed to be clarified.

In order to ensure the normative and operability of the whole flow of the field work of 'Sanpu', the operation flow of field investigation is decomposed and explained in detail; meanwhile, the design of the operation flow and the selection of the technical method can be used for the output of the standard general survey result and the long-term utilization of the general survey data, and attach importance to the connection with the internal industry testing method.

Disclosure of Invention

In view of the above problems in the prior art, the present invention is directed to a soil screening method for producing a standard screening result and utilizing the screening data for a long time.

The technical scheme of the invention is as follows:

a soil census technical method comprises the following steps:

s1, carrying out work preparation on the interior and the exterior of soil general survey, carrying out task decomposition and linkage according to actual field survey work flows of different counties and regions, and training the exterior survey;

s2, designing an interior distribution scheme by combining natural and social economic data, and carrying out field investigation, wherein the natural and social economic data specifically comprise landform and landform, hydrogeology, meteorological data and the current land utilization situation, approaching a preset sampling point position through a handheld terminal App navigation, arriving in a preset sampling point electronic fence range, carrying out sampling point local representative verification, and when a field investigator enters the preset sampling point electronic fence range, determining whether the preset sampling point meets the requirements of target landscape and type, and acquiring a surface layer sample, a field block with the preset sampling point as the center in a radius range of 20-50 m is in the electronic fence range, so that no obvious artificial influence is caused on constructing a ditch, a road, a motor-well and a house, and the land utilization mode is representative; when the range does not meet the expectation, the radius range is extended to the radius range of 100m by taking the preset sampling point as the center, sampling points meeting the conditions are determined, when the sampling point is surveyed on the acquisition profile, the landform, the land utilization current situation, the utilization type, the multiple planting mode and the soil type are relatively consistent within the radius range of 50m by taking the preset sampling point as the center in the range of the electronic fence, and the area where the high-quality landscape unit is located is adjusted to be sampled in the range of the electronic fence according to the requirement of actual survey; if the electronic fence is a plain, a basin or a slow sentry, the electronic fence can be properly extended to 100m but cannot be crossed, a local representative sampling position cannot be found in the electronic fence with the preset sampling points, field adjustment is needed, the actual sampling points are not consistent with the preset sampling points in the range of the electronic fence, adjustment is needed according to a fault-tolerant standard, and sampling and information acquisition work is carried out after the sampling points are reached, representative checking and necessary position adjustment are carried out;

s3, surveying and recording surface layer sampling points and section sampling points, and meanwhile collecting opposite condition information;

s4, recording the topographic features of the surveyed sampling points, classifying the levels, and reasonably utilizing land;

s5, shooting landscape photos in the east, south, west and north directions by using a digital camera and taking a sampling point or a section position as a center;

s6, collecting a surface soil sample by using a multipoint mixed sampling method;

s7, setting the section position, and carrying out mining sampling according to the set section position;

s8, transporting the samples after excavation and sampling, and carrying out sample butt joint on field and interior industries.

The actual field investigation work flow of different counties in the step S1 specifically comprises a point arrangement scheme, sample point implementation, field survey, personnel allocation, sample handover and result check, and the step S1 of carrying out work preparation on the interior and the exterior of soil general survey specifically comprises the following steps:

s11, defining a task foundation of county soil investigation work, and studying soil environment information, soil types, characteristics, distribution conditions and land utilization conditions of an investigation region for actual participants of field investigation work;

s12, developing main soil forming conditions, soil forming processes, soil types and division, field soil investigation and sampling, identification and description of main morphological characteristics, a classification method of the current land utilization situation, training and learning of agricultural utilization situation and farmland construction situation of an investigation region based on second soil general survey and various soil survey data needed by general survey work practice;

s13, familiarizing the work flow of the field practical operation level and possibly having practical problems and solutions;

s14, performing targeted soil generation and soil classification and equipment operation training on the professional knowledge level and the equipment operation skill level of county field survey operators.

Wherein, the fault tolerance standard in step S2 specifically includes: when the construction occupation, the reclamation, the abandoned land or the map spot information is wrong, the deviation of the preset sample point does not refer to the map spot range of the soil map of the level of the Bipu county;

the preset sampling points have relatively small difference of soil types and spaces in plain, basin and slow-hillock areas, the difference of soil landscape, type and soil utilization mode is small, and the adjustment distance is generally within 200m of the boundary of the electronic fence;

the preset sampling points have larger soil type space difference along with the fluctuation change of land shape in hills, hills and fluctuating mountain areas than in plain areas, and the distance is adjusted to search for soil landscape units meeting the conditions within the range from the boundary of the electronic fence to 100 m.

Wherein, the step S3 specifically includes the following steps:

s31, recording the characteristic information of the sampling points;

s311, recording an administrative division, geographic coordinates, altitude, sampling date, weather conditions, investigators and affiliated units of the investigation sample points, uniformly assigning other necessary items except for the sampling date, the weather conditions, the investigators and the affiliated units which need field selection, and performing field approval;

s312, a sampling point code unified coding input system, wherein all the processes use the same code;

s313, recording the location of the sampling point according to the sequence of province (autonomous region, direct prefecture city), city-district (county), village (town) -administrative village; the code is executed according to ISO3166-2 (latest edition) 2007;

s314, referring to a national grid reference system (CGCS 2000 national geodetic coordinate system), wherein the longitude and latitude format adopts a decimal system, and each sampling point is automatically assigned by a positioning device after the position is determined;

s315, altitude unit: rice; the geographic coordinates and the longitude and latitude are collected by a handheld terminal device with an embedded positioning system, and each sampling point is automatically assigned after the positioning is determined;

s316, automatically assigning values by adopting a format of XX month and XX day in 202X year;

s317, selecting the weather condition from options of 'fine or few clouds, partial clouds, cloudy days, rain, sleet and sleet or hail and snow';

s318, adopting by investigators and affiliated units: survey unit: XXXX; the investigator: XX, XX, XX;

s32, recording other information of the earth surface except the soil environment condition and the agricultural production condition of the earth surface characteristics;

s321, erosion describes the process that the soil and the matrix thereof are destroyed, degraded, transported and deposited under the action of water power, wind power, freeze thawing and gravity;

s322, in the landscape or field where the survey sampling point is located, bedrock and large rocks are exposed, direct influence is generated on farmland cultivation, and the exposed abundance and spacing information of the bedrock should be recorded;

s323, the ground surface gravels are generally gravels, stones and boulders which are distributed on the ground surface except for the exposed bedrock, influence the tiltability of a cultivation surface layer, and record abundance and size information;

s324, recording two indexes of abundance and thickness of grey-white or grey-black salt spots formed by cementing soluble salt on the surface salt spots;

s325, recording three indexes of width, length and interval, namely width, of a gap formed in the earth surface due to soil body shrinkage caused by alternation of dryness and wetness in the soil with earth surface cracks rich in sticky particles;

s33, recording the mature soil environment information;

s34, recording the type of the parent rock;

s35, recording the parent substance type;

s36, filling the agricultural condition of the vegetable field facilities for the vegetable fields in the cultivated land types;

s37, recording the influence on agricultural production;

s38, recording the production of the garden;

and S39, recording the forest land production requirement.

Wherein the level classification in step S4 specifically includes: large terrain, medium terrain slope, slope type and slope direction; the large terrain comprises: mountains, hills, plains, plateaus, basins; the medium topography is: extreme high, medium, low; gao Qiu, hillock; marine product plain, alluvial product plain, lake product plain, foot plain, flood plain, and aeolian plain.

When the landscape photos in the step S5 are shot by the unmanned aerial vehicle, the height of the landscape photos is 30-50 meters away from the ground, and landscape photos in the east, south, west and north directions are shot at an inclined visual angle, wherein the landscape photos are to embody sample point geographic landforms, vegetation landscapes, land utilization types, surface features and farmland facility features, and the landscape photos are to be fused with long shot and short shot.

The multipoint mixed sampling method in step S6 specifically includes the following steps:

s61, in the field range where the preset sampling points are located or the range of adjacent and similar landscape parts, one of three methods, namely 5-10 quincunx sample mixing points, 10-15 chessboard-shaped sample mixing points and 15-20 snake-shaped sample mixing points, is adopted;

s62, sampling 1kg of each sample mixing point, removing surface straws, coarse roots and gravels, fully and uniformly mixing all samples collected by the sample mixing points, then removing redundant samples by adopting a quartering method, reserving 3kg of samples, and sampling 5kg of sample points needing to collect parallel samples;

s63, selecting three adjacent sample mixing points when collecting surface layer volume weight samples, and collecting a volume weight repeated sample by using a ring cutter method, wherein the specific operation is as follows:

s631, determining three adjacent mixed sample points as volume weight sampling points, and removing foreign matters affecting volume weight acquisition and data precision of surface leaves and grass roots;

s632, selecting a ground surface leveling part, sleeving the cutting edge-free end of the cutting ring on the cutting ring in a sleeving manner, enabling the cutting edge of the cutting ring to face downwards, uniformly pressing the cutting ring into the soil vertically by virtue of the cutting ring handle and the rubber hammer, and stopping pressing the cutting ring when the soil surface just touches the top of the cutting ring support;

s633, excavating soil around the cutting ring by using a profile cutter, and cutting off the soil below the cutting ring;

s634, taking out the cutting edge upwards, cutting off redundant soil by using a cutter, covering a top cover of the cutting edge, turning over the cutting edge, detaching a cutting edge support, flattening the soil surface without the cutting edge end by using the cutter, and covering a bottom cover;

and S635, three repeated samples, wherein each sample with volume weight is independently contained in a self-sealing bag, and the three repeated samples are collectively contained in the independent self-sealing bag, and are attached with sample labels and labeled with the sample with volume weight.

Wherein, the step S7 specifically includes the following steps:

s71, confirming the sampling positions of the section sampling points, wherein the section positions are in the field, the sample area and the landscape unit;

s72, setting the observation section in the process of selecting and confirming the soil type;

s73, taking a standard section picture as an identity certificate picture of a single soil body of the soil by the section picture;

s74, after the section is excavated and photographed, dividing soil occurrence layers, and naming each occurrence layer;

s75, recording the morphological characteristics of each soil occurrence layer in field investigation;

s76, recording the occurrence layer properties;

s77, recording and dividing soil types;

s78, collecting a profile soil sample, wherein the collecting of the profile soil sample specifically comprises the following steps: collecting a generation layer sample, a paper box sample, a whole section sample, a soil volume weight sample and a soil large aggregate sample;

s79, sample labeling and packaging.

Wherein, the recording of the occurrence layer characters in the step S76 specifically comprises thickness, boundary, color, morphological characteristics, texture and structure of root system, gravel in soil body, gaps in pore soil substance, tightness of soil structure body, and product of re-eluviation deposition and aggregation of substance in soil development process;

the thickness is used for recording the depth of an upper boundary and a lower boundary of each occurrence layer;

the boundary is used for recording the transition condition between adjacent generation layers;

the color is characterized by using a Monser color system;

the morphological characteristics of the root system are the thickness condition and the abundance condition of the root system;

the texture is determined by depending on the proportion of three-phase components of soil sand, powder and clay calculated in a soil laboratory and the texture classification;

the structure is a soil block formed by arrangement and combination of soil particles;

the gravels in the soil body are rocks and mineral debris which can be separated from the soil and are larger than 2 mm.

The invention has the following advantages and beneficial effects: the comprehensive, scientific and professional principles of soil general survey are followed, the existing results are linked, and the past experience method is used for reference. Six combinations are achieved: the quality of the soil is found and the type of the soil is improved; combining soil property general survey and soil utilization survey; the field survey observation and the interior test are combined; combining soil surface layer sampling and key profile sampling; the soil obstacle factor is found out and the measures of improving and fertilizing are provided;

according to the tone and color contrast of the images of the aerial and satellite films in the investigation region, the soil interpretation mark and the typical image are contrasted, the pre-judgment sketch is drawn indoors, and the images are checked outdoors, so that the working efficiency and the investigation quality can be greatly improved, and the general investigation efficiency is improved.

Drawings

FIG. 1 is a schematic cross-sectional view of a standard soil according to the present invention;

FIG. 2 is a transition pattern between soil layers according to the present invention;

FIG. 3 is a soil structure shape of the present invention;

fig. 4 is a soil pore shape of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations. Thus, the following detailed description of the embodiments of the present invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention will be further described with reference to the drawings and specific examples.

As shown in fig. 1 to 4: the technical method for the general survey of the soil comprises the following steps:

s2, designing an interior distribution scheme by combining natural and socioeconomic data, developing field investigation, approaching preset sampling point positions through App navigation of a handheld terminal, arriving in a preset sampling point electronic fence range, and performing sampling point local representative checking, wherein the natural and socioeconomic data specifically comprise landform, hydrogeology, meteorological data and land utilization current situations, the field investigator enters the preset sampling point electronic fence range to determine whether the preset sampling points meet the requirements of target landscape and type, and when a surface layer sample is collected, fields in the 20-50 m radius range by taking the preset sampling points as centers are in the electronic fence range, so that obvious artificial influences of ditch construction, road construction, motor-well construction and house construction are avoided, and the land utilization mode is representative; when the range does not meet the expectation, the radius range is extended to the radius range of 100m by taking the preset sampling point as the center, sampling points meeting the conditions are determined, when the sampling point is surveyed on the acquisition profile, the landform, the land utilization current situation, the utilization type, the multiple planting mode and the soil type are relatively consistent within the radius range of 50m by taking the preset sampling point as the center in the range of the electronic fence, and the area where the high-quality landscape unit is located is adjusted to be sampled in the range of the electronic fence according to the requirement of actual survey; if the electronic fence is a plain, a basin or a slow sentry, the electronic fence can be properly extended to 100m, but the electronic fence cannot be exceeded, and the information which is relatively consistent and does not represent the preset sampling points is completely consistent with the actual situation; starting from the goal of three-common work, the method can be used for ensuring that the soil utilization mode (farming mode and crop type) and the landscape combination (mother matter type, topographic characteristics and hydrological conditions) meet or are close to meet the characteristics of a preset sampling point; according to the requirements of actual investigation, the area where the optimal landscape unit is located can be reasonably adjusted to sample within the electronic fence range, a local representative sampling position cannot be found in the electronic fence of the preset sampling point, field adjustment is needed, the actual sampling point is inconsistent with the preset sampling point within the electronic fence range, adjustment is needed according to a fault tolerance standard, and sampling and information acquisition work is carried out after the actual sampling point reaches the sampling point, and the representative checking and the necessary position adjustment are carried out;

s8, transporting the samples after excavation and sampling, and carrying out sample butt joint on field operation and interior operation.

The actual field investigation work flow of different counties in the step S1 specifically comprises a point arrangement scheme, sample point implementation, field reconnaissance, personnel allocation, sample handover and result check, and the step S1 of carrying out work preparation on the interior and exterior of soil general survey specifically comprises the following steps:

s11, determining a task foundation of county soil investigation work, and learning the information of soil forming environment, soil type, characteristics and distribution conditions of a survey area and land utilization conditions of actual participants of field investigation work;

s12, developing main soil forming conditions, soil forming processes, soil types and division, field soil investigation and sampling, identification and description of main morphological characteristics, a land utilization current situation classification method, training and learning of agricultural utilization conditions and farmland construction conditions, filling vegetable land facility agricultural conditions in farmland types, filling facility agricultural options in facility agricultural types, and filling options of facility agricultural types, wherein the main soil forming conditions, the soil forming processes, the soil types and division, the field soil investigation and sampling are based on second soil general survey and various soil survey data required by general survey work practices: open vegetable fields, plastic greenhouses and glass greenhouses, wherein the planting age of vegetables is filled in the years of continuously planting vegetables; the conditions of agricultural planting system in the field, garden or forest land where the planting system sampling points are located mainly comprise crop rotation system and multiple planting type information. Changing the crop rotation system, and recording abandoned land (perennial and seasonal) for 5 years; ploughing sample points: including rice-rice, wheat-rice, rape-rice, sweet potato-early rice-late rice, rice-vegetables, rice-peanut, rice-tobacco, rape-cotton, wheat-beans, wheat-potatoes, wheat-corn, wheat-spring corn/sweet potato, spring wheat, sweet potato-corn (drought), cotton, potato, wheat-corn-potato, peanut-sweet potato, vegetables; multiple types of ploughing sample points: one-year-one-ripe, two-year-two-ripe, two-year-three-ripe and one-year-three-ripe; filling the crop type with the specific crop type; the specific yield of grain, cotton and oil crops is preferably reported in the yield level, namely kg/mu; the fertilization management text describes the types (commercial organic fertilizer, chemical fertilizer and soil miscellaneous fertilizer), the dosage and the application mode of the fertilizer of the field where the survey sampling point is located. Recording soil fertility improvement measures, which specifically comprise: straw returning, no need of minimal tillage and the age limit thereof, fallow and the age limit thereof, green manure planting variety and season information, concrete description, recording soil fertility treatment measures, and concrete steps of: straw returning, no need of minimal tillage and the age limit thereof, fallow and the age limit thereof, green manure planting variety and season information;

The fault tolerance standard in step S2 specifically includes: when the construction occupation, the reclamation, the abandoned land or the map spot information is wrong, the deviation of the preset sampling point does not refer to the map spot range of the second Puxian county level soil;

the preset sampling points have larger soil type space difference along with the fluctuation change of land shapes than those of flat original areas when the soil types are on hills, hills and fluctuating mountain areas, and the distance is adjusted within 100m from the boundary of the electronic fence to search for a soil landscape unit meeting the conditions.

The step S3 specifically includes the following steps:

s31, recording the characteristic information of the sampling points;

s313, recording the location of the sampling point according to the sequence of province (autonomous region, direct prefecture city), city-region (county), county (town) and administrative village; the code executes as specified in ISO 3166-2;

s315, altitude unit: rice; collecting geographic coordinates and longitude and latitude by using a handheld terminal device embedded with a positioning system, and automatically assigning values after each sampling point is determined;

s318, the investigators and the affiliated units adopt the following steps: survey unit: XXXX; the investigator: XX, XX, XX;

s322, in a landscape or a field where an investigation sample point is located, bedrock and large rocks are exposed and directly affect farmland cultivation, information of exposed abundance and spacing of the bedrock is recorded, the bedrock and the large rocks are rooted in deep soil and cannot move and affect soil cultivation, the abundance is the ratio of the exposed area of the bedrock in the whole soil, the section point is taken as the center, the specific data or the data range is determined in a range of about 100 meters, and the specific data or the data range is recorded;

s325, recording three indexes of width, length and interval, width, recording three indexes of width, length and interval, and width (millimeter) of the soil with earth surface cracks rich in slime due to soil body shrinkage caused by alternation of dryness and wetness: record specific data or data range, length (cm): specific data or data ranges are recorded. Abundance (described): record specific description information, spacing (cm): recording specific data or data ranges;

s33, recording the mature soil environment information;

s34, recording the type of the parent rock;

s35, recording the type of the parent material;

s37, recording the influence on agricultural production;

s38, recording garden production;

and S39, recording the forest land production requirement.

The level classification in step S4 specifically includes: large terrain, medium terrain slope, slope type and slope direction; the large terrain comprises: mountains, hills, plains, plateaus, basins; the medium topography is: extreme high, medium, low; gao Qiu, hillock; sea area plain, alluvial plain, lake area plain, foot plain, hongshan plain, fengcheng plain.

When the landscape photo in the step S5 is shot by the unmanned aerial vehicle, the landscape photos in the east, south, west and north directions are shot at the height of 30-50 meters away from the ground and at the inclined viewing angle, the landscape photo is to embody the geographic landform, the vegetation landscape, the land utilization type, the surface feature and the farmland facility feature of a sampling point, and the landscape photo is to be fused with a long shot and a short shot.

The multipoint mixed sampling method in the step S6 specifically includes the following steps:

s61, in the field range where the preset sampling points are located or the range of the adjacent and similar landscape parts, one of three ways of 5-10 quincunx sample mixing points, 10-15 chessboard sample mixing points and 15-20 snake sample mixing points is adopted;

s62, sampling quantity of each sample mixing point is 1kg, removing surface straws, coarse roots and gravels, fully mixing all samples collected by the sample mixing points, then removing redundant samples by adopting a quartering method, reserving 3kg of samples, and sampling quantity of sample points needing to collect parallel samples is 5kg;

s633, excavating soil around the ring cutter by using a profile cutter, and cutting off the soil below the ring cutter;

s634, taking out the cutting ring cutter, cutting off redundant soil with the cutter, covering a top cover of the cutting ring cutter, turning over the cutting ring cutter, removing a support of the cutting ring cutter, cutting off the soil surface without the cutting edge end with the cutter, and covering a bottom cover;

and S635, three repeated samples, wherein each sample with volume weight is independently contained in a self-sealing bag, three repeated samples are intensively contained in the independent self-sealing bag, sample labels are attached and the sample with volume weight is marked, and a conventional analysis index sample is collected by using a common shovel and a soil drill. Collecting environmental analysis index samples by using stainless steel and bamboo tools, wherein the collection depth is 0-40 cm for field collection, and 0-20cm for other types; if the effective soil thickness is less than 20cm, digging to the plough bottom layer by taking the actual soil thickness as a standard, and measuring and recording the thickness of the plough layer; without a significant plough base, the survey asks the farmer the actual depth of cultivation. In a saline soil area with unit cm, during field investigation, inserting a conductivity meter probe into soil of a sampling point to a specified depth (generally three depths of 0-5 cm, 5-10 cm and 10-20 cm), and reading and recording a numerical value and a unit after the instrument displays a stable numerical value (generally displaying a 'Ready' character); when recording, the numerical unit shown is noted, when the salinization is light, the unit is generally us/cm, and when the salinization degree is high, the unit is changed into ms/cm.

Step S7 specifically includes the following steps:

s72, setting the observation section in the process of selecting and confirming the soil type; the observation profile is mainly used for checking the consistency of soil types, checking the condition of property change of a typical profile and researching the rule of the property change of the soil;

s73, taking a standard section picture as an identity certificate picture of a single soil body of the soil by the section picture; the picture is used as an identity certificate picture of a single soil body of the soil, reflects the occurrence layer and morphological characteristics of the soil and is a direct evidence for knowing and understanding the soil occurrence process and the soil type in the field. Therefore, the standard section photograph should clearly, truly and completely present the morphological description characteristics of the soil and make the description records correspond to the characteristics, and the specific requirements of the standard section photograph are as follows:

after the section is excavated, a natural structural surface is trimmed from top to bottom by a section cutter from 1/3-1/4 of the width of the left side, and the right part is kept as a smooth surface. The rugged natural surface visually reflects the soil structure, texture, new organism type and difference thereof formed at different development stages of the soil, as well as the abundance of root systems, the pore conditions and the animal traces of the soil; correspondingly, the right smooth surface more clearly reflects the thickness of the soil generating layer, the boundary transition characteristics, the color difference and the compaction condition characteristics; the canvas staff gauge is vertically arranged and fixed from top to bottom, and the lens is as vertical as possible to the observation surface during the section photography. The photographer may need to lie on the ground to take a picture, keeping the angle of view of the lens and the direction of the cross section horizontal and centered.

S74, after the section is excavated and photographed, the soil generation layer is divided, the generation layer divides the soil generation layer, the soil layer is formed by leaching, depositing and scattering substances in the soil development forming process and has certain morphological characteristics, and the observation of the morphological characteristics of the section is mainly carried out from two angles of visual characteristics and tactile characteristics:

visual characteristics: macroscopic soil morphological differences including color, root system, gravel, rust spot-nodule-glue film new organism differences, soil structure type and size, difference of invasion of tile ceramic artificial objects, difference of lime reaction strength and weakness and difference of ferrous reaction strength;

tactile characteristics: the difference of soil texture, soil body and soil structure body hardness or tightness and soil moisture condition can be sensed through hand touch.

Dividing each soil occurrence layer and naming each occurrence layer, wherein the capital letters of the main occurrence layer types correspond to the basic soil layers and represent the leaching, precipitation and scattering processes of main substances of the soil; the stratum-added characteristic refers to the mathematical characteristic of the soil stratum. The characteristics of the generation layer are indicated by lower case letters in english juxtaposed behind upper case letters (not subscripts) of the main generation layer. Examples are: ah represents a natural soil humus layer, ap represents a plough layer, and Bt represents a caking layer; the plough layer is a soil surface layer formed under the influence of cultivation for a long time; the plough layer thickness refers to the thickness of the surface soil layer formed by cultivating and curing, the general thickness is 10-20cm, after partial deep ploughing, the thickness can reach 25-30cm, and the plough layer thickness is obviously distinguished from the underlying soil layer. The nutrient content is rich, and the soil has a granular, agglomerate or block structure. The physical properties of moisture and the content of available nutrients in the plough layer are changed seasonally, because the plough layer is often influenced by the disturbance of farm activities and external natural factors. Various soil layers within the frequent cultivation depth can form cultivation layers, and are marked as 'Ap 1'; the plough bottom layer, which is usually called as a 'cultivation surface lower layer or cultivation sub-layer', is a relatively compact soil layer which is positioned below a cultivation surface layer, is extruded by a plough for a long time and is formed by sticky particles along with irrigation and deposition, is commonly found in paddy field soil and part of dry farming soil, has the thickness of 3-5 cm generally and is marked as 'Ap 2'; continuation/subdivision of the occurrence layer or occurrence characteristics: the main generation layer may be further subdivided into several sub-layers depending on the degree to which it occurs. Are represented by Arabic numerals in parallel with capital letters, such as C1, C2, bt1, bt2, bt3;

s76, recording the properties of the occurrence layer;

s77, recording and dividing soil types;

s79, sample labeling and packaging, and profile digging follows the following principle: the section excavation site confirmed based on repeated checking of a plurality of observation sections is representative in landscape parts, soil types and land utilization, and the observation surface is towards the direction of sunlight irradiation, so that shadow blocking is avoided; the upper part of the observation surface strictly prohibits people from walking or stacking objects so as to prevent the interference of observation and sampling caused by soil compaction or displacement of soil substances; the dug surface soil and core soil are separately piled on the left side and the right side of the soil pit, and backfilled according to the original sequence of the soil layers after observation is finished so as to keep the surface soil fertility.

Step S76, recording the occurrence layer properties, which specifically comprises thickness, boundary, color, morphological characteristics, texture and structure of root systems, gravels in soil bodies, gaps in pore soil substances, tightness of soil structure bodies, and products of re-leaching deposition and accumulation of substances in the soil development process;

the color is characterized by using a Monser color system;

gravel in the soil body is rock and mineral debris that are greater than 2mm that can separate out with soil in the soil body, thickness: recording the upper and lower boundary depths of each generation layer, such as 0-15cm, 15-32 cm; if the thickness is a dry branch and fallen leaf layer, the thickness is expressed by negative number, such as "-3-0 cm"; boundary: refers to the transition between adjacent occurring layers. Recording two indexes of transition shape and significance; soil color is represented by a Monser color system, laboratory standard Monser card color comparison is carried out, and in field investigation, simple color comparison is carried out by using a color comparison module provided by a handheld terminal App. If two substances in the same soil layer are mixed with each other and more than two soil ground colors exist, respectively describing different ground colors; describing and recording morphological characteristics of plant (including crops) roots in soil, including thickness and abundance conditions; size: the diameter (mm) can be divided into superfine, thin, medium, thick and very thick; abundance ratio: grade 5-none, no root system; rarely, each 100cm < 2 > contains 1-20 of superfine roots or fine roots or 1-2 of medium, coarse and very coarse roots; few, each 100cm < 2 > contains 20-50 of superfine roots or fine roots or 2-5 of medium, coarse and very coarse roots; in the formula, every 100cm < 2 > contains 50-200 fine roots or at least 5 medium, coarse and very coarse roots; more, every 100cm < 2 > contains at least fine roots; root system properties: judging and recording the root system of woody or herbaceous plants, live roots or rotten roots; root depth: recording the depth of concentrated distribution of root systems in the occurrence layer and the maximum depth which can be reached by the main root or the fibrous root; the soil texture with accurate texture is determined by measuring and calculating the proportion of three-phase components of sand, powder and clay of the soil and the texture classification in a soil laboratory; structure refers to the soil mass formed by the arrangement and combination of soil particles (including agglomerates). In field investigation, the type, size and development degree of soil structure are mainly recorded, and the following points should be noted during observation: observing the soil structure preferably under the condition of soil water content, and spraying water with a watering can in a proper amount; when there are two or more structures, they should be recorded separately; at the time of observation, attention should be paid to the type of cementitious substance (humus cementation, carbonate cementation, iron-aluminium oxide cementation, silicic acid cementation); paying attention to the structural difference between the upper part and the lower part of a section generation layer, the gravels in the soil body refer to rocks and mineral debris which can be separated from the soil and are larger than 2 mm.

Specifically, when the system is used, the working preparation is carried out on the interior and the exterior of the soil general survey, the task decomposition and the linkage are carried out according to the actual field survey working flows of different counties, and the field survey is trained, the actual field survey working flows of different counties specifically comprise a stationing scheme, sample spot implementation, on-site survey, personnel allocation, sample handover, result check, the county soil survey working task basis is defined, the study on the soil environment information, the soil type, the characteristic and the distribution condition and the land utilization condition of a survey area is carried out on the actual participants of the field survey work, the main soil forming conditions, the soil forming process, the soil type and the division, the field soil survey and the sampling, the identification and the description of the main morphological characteristics, the classification method of the land utilization current situation, the training and the learning of the agricultural land utilization situation and the farmland construction situation required by the practice of the general survey work are carried out, familiarizing the basic workflow and possible actual problems and solutions of field practical operation level, carrying out targeted soil generation and soil classification and equipment practical operation training on the professional knowledge level and equipment control skill level of county field survey practical operators, carrying out the design of an interior distribution scheme by combining the current situations of landform, geology, meteorological data and land utilization, carrying out field survey, approaching to preset sampling point positions through the App navigation of a handheld terminal, arriving in the range of a preset sampling point electronic fence, carrying out local representative verification on sampling points, entering the range of the preset sampling point electronic fence by the field surveyor, determining whether the preset sampling points meet the requirements of target landscape and type, and in the range of the electronic fence when acquiring surface layer samples, the field blocks with the radius of 20-50 m by taking the preset sampling points as the center have no obvious artificial influence on building ditches, roads, motor-pumped wells and houses, and the land utilization mode is representative; when the range does not meet the expectation, the radius range is extended to the radius range of 100m by taking the preset sampling point as the center, sampling points meeting the conditions are determined, when the sampling point is surveyed on the acquisition profile, the landform, the land utilization current situation, the utilization type, the multiple planting mode and the soil type are relatively consistent within the radius range of 50m by taking the preset sampling point as the center in the range of the electronic fence, and the area where the high-quality landscape unit is located is adjusted to be sampled in the range of the electronic fence according to the requirement of actual survey; if the site is a plain, a basin or a slow sentry, the site can be properly extended to 100m but cannot exceed the electronic fence, a local representative sampling position cannot be found in the preset sample point electronic fence, the site adjustment is needed, the actual sample point is not consistent with the preset sample point in the electronic fence range and needs to be adjusted according to a fault tolerance standard, the sample point is reached, the sampling and information acquisition work is carried out after the representative verification and the necessary position adjustment are carried out, the fault tolerance standard is that the deviation of the preset sample point can not refer to the range of the map spots of the soil in Bipu county level when the construction occupation, the reclamation, the abandoned land or the map spots have wrong information, the preset sample point has relatively small difference in soil type space in the plain, basin and slow sentry areas, the difference in soil landscape, type and soil utilization mode is small, the adjustment distance is generally within 200m of the electronic fence boundary, the preset sampling points have larger spatial difference of soil types along with the fluctuation change of land shapes in hills, hills and fluctuating mountain areas, soil landscape units meeting the conditions are searched and recorded in the range from the boundary of an electronic fence to 100m by adjusting the distance, meanwhile, the condition information of the opposite land is collected, the characteristic information of the sampling points is recorded, the administrative, geographic coordinates, altitude, sampling date, weather conditions, investigators and affiliated units of the investigation sampling points are recorded, except for the three items of the sampling date, the weather conditions, the investigators and the affiliated units which need to be checked in the field, other necessary filling items are uniformly assigned, the field is verified, the sampling point codes are uniformly coded into a system, all the processes use the same code, and the sequence of province (autonomous region, direct market) -city-district (prefecture) -county (town) -administrative region is according to the sequence, and recording the location of the sampling point. The code is executed according to the specification of ISO3166-2 (latest edition) 2007, and by referring to a national grid reference system (CGCS 2000 national geodetic coordinate system), the longitude and latitude format adopts a decimal system, each sampling point is automatically assigned by a positioning device after the positioning is determined, and the altitude unit is as follows: and (4) rice. The geographic coordinates and the longitude and latitude are collected by a handheld terminal device of an embedded positioning system, each sampling point is automatically assigned after the positioning is determined, the date is in a format of XX month XX day in 202X years, such as 08 month 05 in 2022, the automatic assignment is carried out, the weather condition is selected from options of 'fine or few clouds, partial clouds, cloudy, rain, sleet or hail, snow', and the surveyor and the affiliated units adopt the following steps: survey unit: XXXX; the investigator: XX, XX, XX, to the earth's surface other information except the soil environment condition and the agricultural production situation, the erosion describes the process that the soil and its matrix is destroyed, denudation, transportation and deposition under the action of hydraulic power, wind power, freeze thawing, gravity, external force, in the landscape or field where the survey sampling point is located, there is bedrock and big rock exposed, which directly affects the farmland cultivation, the information of the exposed abundance and the interval of bedrock should be recorded, the earth's surface gravel is generally the gravel, stone and boulder distributed on the earth's surface except the exposed bedrock, which affects the cultivation surface layer tiltability, the information of abundance and size is recorded, the earth's surface salt spot is gray-white or gray-black salt spot formed by soluble salt glue, recording two indexes of abundance and thickness, soil with earth surface cracks rich in clay grains is caused by soil body shrinkage due to dry-wet alternation to form gaps on the earth surface, recording three indexes of width, length and space, width, recording soil formation environment information, recording a parent rock type, recording a parent quality type, filling vegetable land in cultivated land types, reporting agricultural conditions of vegetable land facilities, recording the influence of agricultural production, recording garden production, requiring recording forest land production, recording the topographic features of sample points, terrains and landforms of investigation and classifying the terrains, and dividing the terrains into a large terrain, a medium terrain slope, a slope type and a slope direction, wherein the large terrain is divided into: mountain region, hills, plain, plateau, basin, well topography divide into: extreme high, medium, low; gao Qiu, hillock; the method comprises the following steps of reasonably utilizing land, shooting landscape photos in east, south, west and north directions by using a digital camera with a sampling point or a section position as a center, shooting the landscape photos in east, south, west and north directions by using an unmanned aerial vehicle, wherein the landscape photos are 30-50 m away from the ground and shot in the east, south, west and north directions at an inclined visual angle, the landscape photos show geographical landforms, vegetation landscapes, land utilization types, surface characteristics and farmland facility characteristics of sample points, the landscape photos are fused with a long view and a short view, and one of three methods of 5-10 plum blossom-shaped mixed sample points, 10-15 chessboard-shaped mixed sample points and 15-20 snakelike mixed sample points is adopted in a field range of a preset sample point or in an adjacent and similar landscape position range, wherein 1kg of sampling amount of each mixed sample point is used for removing surface straws, rough roots and gravels, all mixed sample points are fully mixed, then a ' four-point mixing method ' is adopted for removing ' and a sample is adopted, a specific sample is selected and used repeatedly, and when the sample is collected in an adjacent mixed sample point, the method comprises the following steps of collecting and the following steps: determining three adjacent mixed sample points as volume weight sampling points, removing foreign matters affecting volume weight acquisition and data precision of leaves and grass roots on the earth surface, selecting a flat part on the earth surface, sleeving a cutting edge-free end of a cutting ring on the cutting ring, pressing the cutting ring into the earth uniformly by using a cutting ring handle and a rubber hammer, stopping pressing the cutting ring downwards when the earth surface just touches the top of the cutting ring support, slightly digging out the soil around the cutting ring by using a section cutter, cutting off the soil below the cutting ring, taking out the cutting ring with the cutting edge upwards, cutting off the redundant soil by using a cutter, covering a top cover of the cutting ring and turning over the cutting ring, detaching the cutting ring support, flattening the soil surface without the cutting edge end by using the cutter, covering a bottom cover, three repeated samples, each volume weight sample uses valve bag splendid attire alone, three repeated concentrated packing is into solitary valve bag, and attached sample label, mark the volume weight sample and gather surface layer soil sample, set up the profile position, and excavate the sampling through the profile position that sets up, confirm the sampling position of profile appearance point, the profile position is in the field piece of locating, the sample district, the view unit, it sets up at selection and affirmation soil type in-process to observe the profile, the profile photo is shot standard profile and is regarded as "certificate identity photo" of soil single soil body, excavate the profile, after shooing, take photo, take place the level to divide to soil, the subdivision on layer takes place for the characteristic: some of the property generating layers (p, r, s) are further subdivided by differences in their generating properties. For example, the Ap layer (surface layer affected by cultivation) is divided into an Ap1 layer (cultivation layer) and an Ap2 layer (plough layer), the Br layer (rice soil retention layer) is divided into a Br1 layer (iron deposition layer) and a Br2 layer (manganese deposition layer), and the Bs layer (autotype soil iron manganese deposition layer) is divided into a Bs1 layer (iron deposition layer) and a Bs2 layer (manganese deposition layer). Note that the small Arabic numerals are juxtaposed with English lowercase letters; when the subdivision characteristic generation layer can divide a plurality of sub-layers according to the development degree or the development sequence, small Arabic numerals are juxtaposed behind English lowercase letters and the small Arabic numerals which represent the subdivision characteristic generation layer, and the heterologous mother soil layer represents: represented by arabic numerals placed in front of the symbols of the occurrence layer. For example, in the following sequence of generation layers of binary matrix soil profiles (A-E-Bt 1-Bt2-2Bt 3-2C-2R), A-E-Bt1-Bt2 is a generation layer developed by the substance "1" (the Arabic numeral 1 may be omitted), and 2Bt3-2C-2R is a soil layer developed by the substance "2"; of which 3 lake layers still have to be represented continuously, transition layers represent: the capital letters representing the upper and lower occurrence layers are used for writing together, and the soil layer letters representing the main characteristics are placed in front. Such as an AB layer. Two generation layers with tongue-shaped and finger-shaped soil layer boundary lines are arranged between the two generation layers by using slash separating marks (/), and the upper capital letters represent that the generation layers are mainly arranged in the whole finger-shaped soil layer. E.g., an E/B layer; the standard provides 'main generation layer naming and symbol standard' of national soil for field description and naming of each generation layer, the field investigation shall record morphological characteristics of each soil generation layer and record generation layer properties, specifically comprises thickness, boundary, color, morphological characteristics of root systems, texture, structure, gravels in soil bodies, gaps in pore soil substances, tightness of soil structural bodies and products of re-elution, deposition and aggregation of substances in the soil development process, the thickness is used for recording upper and lower bound depths of each generation layer, the boundary is used for recording transition conditions between adjacent generation layers, the color is used for representing soil color by using a Monser color system, the morphological characteristics of the root systems are the conditions and abundance conditions of the root systems, the texture is used for measuring and calculating soil, powder and clay phase sand components and the proportion of the clay phase components, and the classification method is used for determining the field investigation by adopting the following simple classification method: sand and soil: loose single grain particles, single sand grains can be seen or felt. If the dry powder is held in the hand, the powder can be scattered after being slightly loosened, and the powder can be in a lump when being moistened, but can be scattered after being collided; sandy loam: when the water is dry, the water is held into a ball by hand, but the water is easy to scatter, and when the water is moistened, the water is held into a ball and then carefully taken up by hand, so that the water cannot scatter; loam: soft and gritty, smooth, slightly sticky. When dry, the mixture is held into a ball by hand and cannot be scattered when carefully taken up by hand; when the paste is moistened, the paste is held into a ball, and is generally touched to not disperse; and (2) soil pulverizing: the powder is easy to be broken when dried, and is soft and powdery after being crushed. When moistened, the product is formed into a mass which is plastic daub. When dry and moist, the formed lumps can be taken up conveniently without being dispersed. Twisting with thumb and forefinger to form broken strips when wet; clay loam: the soil is in a block shape after being crushed, and the soil is hard when being dried. Wet soil can be twisted into strips with the thumb and forefinger, but often cannot withstand its own weight. The soil is plastic when moist, is held into a ball by a hand, is not easy to be scattered when being taken up by the hand, and is changed into a solid soil ball; clay: dry is often a hard clod, and wet is extremely plastic. Usually, the plastic soil strips are formed by rubbing between fingers, the structure is a soil block formed by arranging and combining soil particles, and the holding property refers to the hardness and elasticity of a soil structure. In field investigations, the ease of crushing when squeezed in the hand. The method mainly comprises the following steps: loosening: the soil substances have no adhesiveness (after the two fingers are mutually extruded, no soil substances are attached to hands); softening: crushing under the action of slight pressure between thumb and forefinger; slightly solid: the soil substance has certain compressive resistance and is easy to crush between the thumb and the forefinger; hard: the soil substance has medium compression resistance, is extremely difficult to crush between the thumb and the forefinger, but can be crushed when being squeezed by the whole hand; is very hard: the soil substance has strong compression resistance and is easy to crush only when the soil substance is fully stressed by hand; extremely hard: cannot be crushed in the hand. The gravel in the soil body is rocks and mineral debris which can be separated from the soil and are larger than 2mm, the soil type is recorded and divided, and a profile soil sample is collected, wherein the profile soil sample collection specifically comprises the following steps: the method comprises the steps of generation layer sample collection, paper box sample collection, whole section sample collection, soil volume weight sample collection and soil large aggregate sample collection, wherein a sample label and a package are used for transporting the samples after excavation and sampling and carrying out sample butt joint on field operation and interior operation.

Finally, it should be noted that: the above-mentioned embodiments are only used for illustrating the technical solution of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A soil census technical method is characterized by comprising the following steps:

s2, designing an interior distribution scheme by combining natural and socioeconomic data, and developing field investigation, wherein the natural and socioeconomic data specifically comprise landform, hydrogeology, meteorological data and land utilization current situations, approaching to preset sampling point points through App navigation of a handheld terminal, arriving in a preset sampling point electronic fence range, carrying out sampling point local representative verification, and when a field investigator enters the preset sampling point electronic fence range, determining whether the preset sampling points meet the requirements of target landscape and type, taking the preset sampling points as fields within a radius range of 20-50 m in the electronic fence range when acquiring surface layer samples, wherein the fields do not have obvious artificial influence on constructing ditches, roads, motor shafts and houses, and have representative land utilization modes; when the range does not meet the expectation, the radius range is extended to the radius range of 100m by taking the preset sampling point as the center, sampling points meeting the conditions are determined, when the sampling point is surveyed on the acquisition profile, the landform, the land utilization current situation, the utilization type, the multiple planting mode and the soil type are relatively consistent within the radius range of 50m by taking the preset sampling point as the center in the range of the electronic fence, and the area where the high-quality landscape unit is located is adjusted to be sampled in the range of the electronic fence according to the requirement of actual survey; if the electronic fence is a plain, a basin or a slow post, the electronic fence can be properly extended to 100m but cannot be overtopped, a local representative sampling position cannot be found in the electronic fence of the preset sampling point, field adjustment is needed, the actual sampling point is inconsistent with the preset sampling point within the range of the electronic fence, adjustment is needed according to a fault-tolerant standard, and sampling and information acquisition work is carried out after the sampling point is reached, representative checking is carried out, and necessary position adjustment is carried out;

s3, investigating and recording surface layer sample points and section sample points, and simultaneously acquiring opposite condition information;

s7, setting the section position, and excavating and sampling according to the set section position;

2. The soil general survey technical method according to claim 1, wherein the actual field survey work flow of different counties in the step S1 specifically includes a point arrangement scheme, a sample point implementation, a field survey, a personnel deployment, a sample handover, and a result check, and the step S1 specifically includes the following steps:

3. The soil screening technique of claim 2, wherein the fault tolerance criteria in step S2 specifically include: when the construction occupation, the reclamation, the abandoned land or the map spot information is wrong, the deviation of the preset sample point does not refer to the map spot range of the soil map of the level of the Bipu county;

the preset sampling points have relatively small difference of soil types and spaces in plain, basin and slow-hillock areas, the difference of soil landscape, types and soil utilization modes is small, and the adjustment distance is generally within 200m of the boundary of the electronic fence;

4. The soil screening technical method according to claim 3, wherein the step S3 specifically comprises the following steps:

s31, recording the characteristic information of the sampling points;

s317, selecting the weather condition from options of 'fine or few clouds, partial clouds, overcast, rain, sleet or hail, snow';

s318, the investigators and the affiliated units adopt the following steps: survey units: XXXX; the investigator: XX, XX, XX;

s321, eroding the soil and the matrix thereof to be destroyed, degraded, transported and deposited under the action of water power, wind power, freeze thawing and gravity;

s325, recording three indexes of width, length and interval, namely width, of a gap formed on the earth surface due to soil body shrinkage caused by alternate wetting and drying of soil with earth surface fractures rich in slime;

s33, recording the mature soil environment information;

s34, recording the type of the parent rock;

s35, recording the parent substance type;

s37, recording the influence on agricultural production;

s38, recording the production of the garden;

and S39, recording the production requirements of the forest land.

5. The soil screening technical method according to claim 4, wherein the classification of the grade in the step S4 specifically comprises: large terrain, medium terrain slope, slope type and slope direction; the large terrain comprises: mountains, hills, plains, plateaus, basins; the medium topography is: extreme high, medium, low; gao Qiu, hillock; sea area plain, alluvial plain, lake area plain, foot plain, hongshan plain, fengcheng plain.

6. The soil survey technical method as set forth in claim 5, wherein the landscape photos in step S5 are shot at an oblique view angle from 30-50 m above the ground, and show geographic landform, vegetation landscape, land utilization type, surface features, and farmland facility features, and are fused with long-distance view and short-distance view.

7. The soil census technical method of claim 6, wherein the multipoint mixed sampling method in step S6 specifically comprises the steps of:

s632, selecting a ground surface leveling part, sleeving the cutting edge-free end of the cutting ring with the cutting edge of the cutting ring facing downwards, uniformly and vertically pressing the cutting ring into the soil by virtue of the cutting ring handle and the rubber hammer, and stopping pressing the cutting ring downwards when the soil surface just touches the top of the cutting ring support;

8. The soil screening technical method according to claim 7, wherein the step S7 specifically comprises the steps of:

s72, setting an observation profile in the process of selecting and confirming the soil type;

s76, recording the occurrence layer properties;

s77, recording and dividing soil types;

s78, collecting a section soil sample, wherein the section soil sample collecting specifically comprises the following steps: collecting a generation layer sample, a paper box sample, a whole section sample, a soil volume weight sample and a soil large aggregate sample;

s79, sample labeling and packaging.

9. The soil screening technical method of claim 8, wherein the step S76 of recording the occurrence layer properties includes thickness, boundary, color, morphological characteristics of root system, texture, structure, gravel in soil body, voids in porous soil material, tightness of soil structure, and products of re-elution precipitation and aggregation of material during soil development;

the color is characterized by using a Monser color system;