CN109060676A - Based on the determination method of the Summer Corn Canopy SPAD value appraising model of EO-1 hyperion - Google Patents
Based on the determination method of the Summer Corn Canopy SPAD value appraising model of EO-1 hyperion Download PDFInfo
- Publication number
- CN109060676A CN109060676A CN201810727612.9A CN201810727612A CN109060676A CN 109060676 A CN109060676 A CN 109060676A CN 201810727612 A CN201810727612 A CN 201810727612A CN 109060676 A CN109060676 A CN 109060676A
- Authority
- CN
- China
- Prior art keywords
- summer corn
- spad value
- canopy
- spad
- summer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/27—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands using photo-electric detection ; circuits for computing concentration
Abstract
The invention discloses a kind of determination methods of Summer Corn Canopy SPAD value estimation models based on EO-1 hyperion, by to the data monitorings such as influences of plant crown EO-1 hyperion and influences of plant crown blade SPAD value and analysis, establish Summer Corn Canopy SPAD value and sensitive band, causes between spectral index, pass through the variation characteristic of summer corn influences of plant crown spectral reflectivity under small precast unit analysis of experiments difference SPAD value, determine the response relation of summer corn influences of plant crown original spectrum and its first differential and canopy SPAD value, filter out the sensitive band in time of infertility monitoring Summer Corn Canopy SPAD value and optimal spectral index, with promote hyperspectral technique summer corn liquid manure Precision management and quickly, application in lossless Growing state survey.
Description
Technical field
The invention belongs to agriculture and forestry technical fields, and in particular to a kind of Summer Corn Canopy SPAD (" soil based on EO-1 hyperion
The abbreviation of crop analysis instrument development ", Soil and Plant Analyzer Development) value appraising model determination
Method.
Background technique
Chlorophyll content is an important biochemical parameter in growing process, to vegetation photosynthetic capacity, stage of development
And nutrition condition has indicative function.Compared to traditional chlorophyll measuring method, high-spectrum remote-sensing has high-resolution light
Spectrum information can differentiate the faint variation of crop canopies spectral information, thus can quickly, nondestructively realize to plant growth and
The monitoring of nutrition condition.But the chlorophyll content based on leaf scale only characterizes individual plants information, and the information that remote sensing obtains
Then correspond to the chlorophyll content of canopy.Therefore in real time observation crop canopies chlorophyll content variation to crop condition monitoring, apply
Fertilizer regulation is of great significance with yield assessment.
High-spectrum remote-sensing is applied to crop field since at the end of the 20th century, makees in wheat, cotton, rice, soybean, corn etc.
Object chlorophyll content monitoring aspect has carried out correlative study, analyzes between plant chlorophyll content and spectral reflectivity
Correlation establishes the spectral index of monitoring chlorophyll content.In existing correlative study, pass through research discovery in the first scheme
Band po sition at maize leaf SPAD value and original spectrum and its first derivative correlation maximum is basic between different year
It is constant；Find that spectrum parameter RVI (660,717) and NDVI (610,460) can preferably estimate rice color in second scheme
Cellulose content；Point out that the prediction model constructed based on LCI, DSI (678,717) and DSI (549,678) can in the third scheme
With Accurate Prediction corncob position leaf SPAD value；Pass through the phase of research wheat spectral reflectivity and chlorophyll density in 4th kind of scheme
Closing property points out that sensitive band is located in red spectral range；It is that wheat is estimated using unified spectral index there are also a kind of scheme
Chlorophyll content, and the chlorophyll content estimation models established.Ongoing research at present is mainly green using spectrum estimation leaf
The feasibility and its basic skills of cellulose content, it is logical but without establishing one although there are also simple researchs about summer corn
With and the higher Summer Corn Canopy chlorophyll content appraising model of precision.
Summary of the invention
For above-mentioned deficiency in the prior art, the Summer Corn Canopy SPAD value estimation provided by the invention based on EO-1 hyperion
The determination method of model, which realizes, utilizes the more acurrate quick estimation Summer Corn Canopy SPAD value of hyperspectral technique.It is above-mentioned in order to reach
Goal of the invention, the technical solution adopted by the present invention are as follows: a kind of Summer Corn Canopy SPAD value appraising model based on EO-1 hyperion is really
Determine method, comprising the following steps:
S1, using small precast unit experimental cultivation summer corn, and monitor Summer Corn Canopy original spectrum reflectivity and
SPAD value；
S2, resampling is carried out to original spectrum reflectivity and is exported, and determine its first derivative spectra；
S3, correlation point is carried out with original spectrum reflectivity and the first derivative spectra respectively to the SPAD value of Summer Corn Canopy
Spectrum wave corresponding to the original spectrum reflectivity and the first derivative spectra of analysis, determination and summer corn SPAD value correlation maximum
Section；
Spectral band corresponding to the original spectrum reflectivity and the first derivative spectra is respectively to reflect in original spectrum
The most sensitive wave band of rate, the first derivative spectra monitoring Summer Corn Canopy SPAD value；
S4, optimal bands composite is obtained by multivariate analysis in regressive to the most sensitive wave band of Summer Corn Canopy；
S5, the optimal spectral index of Summer Corn Canopy SPAD value is determined；
S6, original spectrum reflectivity, the first derivative spectra, optimal band group with SPAD value correlation maximum are based respectively on
It closes and optimal spectral index establishes summer corn influences of plant crown SPAD value appraising model；
S7, it is tested, is determined most to four summer corn influences of plant crown SPAD value appraising models by model-evaluation index
Excellent summer corn SPAD value appraising model.
Further, the method for Summer Corn Canopy original spectrum reflectivity is measured in the step S1 specifically:
Summer Corn Canopy original spectrum reflectivity is monitored within summer corn breeding time by spectrometer, in monitoring process, into
The correction of row standard white plate carries out spectral reflectivity monitoring to several plants of summer corns in each small precast unit, if then should
Original spectrum reflectivity of the arithmetic average of dry spectral reflectivity as the Summer Corn Canopy of the small precast unit；
The monitoring parameters of the Summer Corn Canopy original spectrum reflectivity are arranged are as follows: and spectral band is 325nm~1075nm,
The monitoring sampling interval is 1nm, and spectral resolution 3nm, monitoring time is daily 10 points~14 points, and spectrometry sensor device probe hangs down
Straight spectrometer field angle is 25 ° downwards, is 10~20cm apart from Summer Corn Canopy top vertical height.
Further, the method for Summer Corn Canopy SPAD value is monitored in the step S1 specifically:
Summer Corn Canopy SPAD value is monitored in summer corn breeding time by chlorophyll meter, by the of Summer Corn Canopy expansion
Two, three blades choose middle part of blade as monitoring sampling point, when monitoring and avoid vein, each several SPAD of sampling point random measurement
Value, takes the average value of all SPAD values of same small precast unit as small precast unit SPAD value.
Further, the step S2 specifically:
The original spectrum reflectivity data of monitoring is subjected to resampling by the processing software of spectrometer and is exported, to original
Spectral reflectance data seeks first differential, and extract from the first derivative spectra blade it is red while, it is blue while and yellow side parameter, use
In the SPAD value of Summer Corn Canopy and the correlation analysis of the first derivative spectra；
Wherein, sampling interval 1nm.
Further, jointing stage, tasseling stage, pustulation period and the maturity period in summer corn breeding time are both needed in each small-sized steaming
It seeps and chooses the monitoring that several Summer Corn Canopies carry out original spectrum reflectivity and SPAD value in instrument.
Further, the step S3 specifically:
Calculate the related coefficient of Summer Corn Canopy SPAD value and original spectrum reflectivity and the first derivative spectra, determining and summer
Spectral band corresponding to the original spectrum reflectivity and the first derivative spectra of corn SPAD value correlation maximum；
The calculation formula of the correlation coefficient r are as follows:
In formula, n is actual measurement number；
xiFor the spectral reflectivity or the first derivative spectra of i-th of Summer Corn Canopy；
For the average value or the first derivative spectra average value of the spectral reflectivity of i-th of Summer Corn Canopy；
yiFor i-th of Summer Corn Canopy SPAD value；
For the average value of i-th of Summer Corn Canopy SPAD value.
Further, the step S4 specifically:
Using method of gradual regression, within the scope of Summer Corn Canopy 325nm~1075nm spectral reflectivity and SPAD value into
Row regression analysis obtains the optimal bands composite of summer corn influences of plant crown.
Further, the step S5 specifically:
Based on 73 SPAD value spectrum monitoring indexes, by being planted to each SPAD value spectrum monitoring index and summer corn
Canopy layer SPAD value carries out correlation analysis and determines the optimal spectral index of Summer Corn Canopy according to its related coefficient.
Further, four summer corn influences of plant crown SPAD value appraising models are quadratic term side in the step S6
Formula.
Further, the evaluation index in the step S7 is the coefficient of determination, root-mean-square error and mean absolute error.
The invention has the benefit that the Summer Corn Canopy SPAD value appraising model provided by the invention based on EO-1 hyperion
Determine method, using summer corn as research object, field spectroradiometer is technical support in a handheld, to the different chlorophyll content lower summers
Maize canopy spectral signature is studied, and by the correlation between analysis Summer Corn Canopy SPAD value and canopy spectra, is determined
The spectrum sensitive wave band of Summer Corn Canopy SPAD value and optimal SPAD value appraising model.It is small in Summer Corn Canopy data monitoring
The test of type lysimeter, it is more accurate to hold to different parameters processing, and smaller, acquisition is interfered by various factors compared to field experiment
Data and the conclusion that obtains it is more accurate；It is studied in the method for the present invention for time of infertility Summer Corn Canopy, compared to single
One key developmental stages data modeling, time of infertility sample data is abundant, improves the reliability of appraising model；And compared to summer jade
Rice leaf scale research, canopy scale research conclusion are of great significance to areal study.
Detailed description of the invention
Fig. 1 is in embodiment provided by the invention based on the determination method of the summer corn layer SPAD value appraising model of EO-1 hyperion
Flow chart.
Fig. 2 is Summer Corn Canopy SPAD value comparison diagram under nitrogen amount applieds different in embodiment provided by the invention.
Fig. 3 is yield of Summer Corn comparison diagram under nitrogen amount applieds different in embodiment provided by the invention.
Fig. 4 is Summer Corn Canopy spectral signature curve in different bearing in embodiment provided by the invention.
Fig. 5 is Summer Corn Canopy spectral signature curve under nitrogen amount applieds different in embodiment provided by the invention.
Fig. 6 is the related coefficient curve of Summer Corn Canopy spectral reflectivity and SPAD value in embodiment provided by the invention.
Fig. 7 is the first derivative spectra of Summer Corn Canopy spectral reflectivity and SPAD value in embodiment provided by the invention
Related coefficient curve.
Specific embodiment
A specific embodiment of the invention is described below, in order to facilitate understanding by those skilled in the art this hair
It is bright, it should be apparent that the present invention is not limited to the ranges of specific embodiment, for those skilled in the art,
As long as various change is in the spirit and scope of the present invention that the attached claims limit and determine, these variations are aobvious and easy
See, all are using the innovation and creation of present inventive concept in the column of protection.
As shown in Figure 1, a kind of determination method of the Summer Corn Canopy SPAD value appraising model based on EO-1 hyperion, including it is following
Step:
S1, using small precast unit experimental cultivation summer corn, and monitor Summer Corn Canopy original spectrum reflectivity and
SPAD value；
The method of Summer Corn Canopy original spectrum reflectivity is measured in above-mentioned steps S1 specifically:
Summer Corn Canopy original spectrum reflectivity is monitored within summer corn breeding time by spectrometer, in monitoring process, and
Shi Jinhang standard white plate correction (standard white plate reflectivity is 1, therefore object spectrum is relative reflectance), in order to accurately survey
Next processing is measured, spectral reflectivity monitoring is carried out to several plants of summer corns in each small precast unit, then by several light
Original spectrum reflectivity of the arithmetic average of spectrum reflectivity as the Summer Corn Canopy of the small precast unit；
The monitoring parameters of above-mentioned Summer Corn Canopy original spectrum reflectivity are arranged are as follows: and spectral band is 325nm~1075nm,
The monitoring sampling interval is 1nm, and spectral resolution 3nm, monitoring time is daily 10 points~14 points, and spectrometry sensor device probe hangs down
Straight spectrometer field angle is 25 ° downwards, is 10~20cm apart from Summer Corn Canopy top vertical height.
The method of Summer Corn Canopy SPAD value is monitored in above-mentioned steps S1 specifically:
Summer Corn Canopy SPAD value is monitored in summer corn breeding time by chlorophyll meter, by the of Summer Corn Canopy expansion
Two, three blades choose middle part of blade as monitoring sampling point, when monitoring and avoid vein, each several SPAD of sampling point random measurement
Value, takes the average value of all SPAD values of same small precast unit as small precast unit SPAD value.
Jointing stage, tasseling stage, pustulation period and maturity period in summer corn breeding time are both needed to select in each small precast unit
Several Summer Corn Canopies are taken to carry out the monitoring of original spectrum reflectivity and SPAD value.
S2, resampling is carried out to original spectrum reflectivity and is exported, and determine its first derivative spectra；
Above-mentioned steps S2 specifically:
Before carrying out Data Management Analysis, using spectrometer processing software by the original spectrum reflectivity data of monitoring into
Row resampling simultaneously exports, sampling interval 1nm；In order to propose the influence of Soil Background, atmospheric scattering and improve different absorptions spies
The contrast of sign seeks first differential to original spectrum reflectivity data, and red side, the indigo plant of blade are extracted from the first derivative spectra
The parameters such as while with yellow, for the SPAD value of Summer Corn Canopy and the correlation analysis of the first derivative spectra；
S3, correlation point is carried out with original spectrum reflectivity and the first derivative spectra respectively to the SPAD value of Summer Corn Canopy
Spectrum wave corresponding to the original spectrum reflectivity and the first derivative spectra of analysis, determination and summer corn SPAD value correlation maximum
Section；
Spectral band corresponding to above-mentioned original spectrum reflectivity and the first derivative spectra be respectively original spectrum reflectivity,
The most sensitive wave band of the first derivative spectra monitoring Summer Corn Canopy SPAD value；
Above-mentioned steps S3 specifically:
Calculate the related coefficient of Summer Corn Canopy SPAD value and original spectrum reflectivity and the first derivative spectra, determining and summer
Spectral band corresponding to the original spectrum reflectivity and the first derivative spectra of corn SPAD value correlation maximum；
The calculation formula of the correlation coefficient r are as follows:
In formula, n is actual measurement number；
xiFor the spectral reflectivity or the first derivative spectra of i-th of Summer Corn Canopy；
For the average value or the first derivative spectra average value of the spectral reflectivity of i-th of Summer Corn Canopy；
yiFor i-th of Summer Corn Canopy SPAD value；
For the average value of i-th of Summer Corn Canopy SPAD value.
S4, optimal bands composite is obtained by multivariate analysis in regressive to the most sensitive wave band of Summer Corn Canopy；
Above-mentioned steps S4 specifically:
Using Stepwise Regression Method, to the spectral reflectivity and SPAD within the scope of Summer Corn Canopy 325nm~1075nm
Value carries out regression analysis, obtains the optimal bands composite of summer corn influences of plant crown.
S5, the optimal spectral index of Summer Corn Canopy SPAD value is determined；
Above-mentioned steps S5 specifically:
Based on 73 SPAD value spectrum monitoring indexes, by being planted to each SPAD value spectrum monitoring index and summer corn
Canopy layer SPAD value carries out correlation analysis and determines the optimal spectral index of Summer Corn Canopy according to its related coefficient.
S6, original spectrum reflectivity, the first derivative spectra, optimal band group with SPAD value correlation maximum are based respectively on
It closes and optimal spectral index establishes summer corn influences of plant crown SPAD value appraising model；
Four summer corn influences of plant crown SPAD value appraising models are quadratic term equation in above-mentioned steps S6.
S7, it is tested, is determined most to four summer corn influences of plant crown SPAD value appraising models by model-evaluation index
Excellent summer corn SPAD value appraising model.
Evaluation index in above-mentioned steps S7 is the coefficient of determination, root-mean-square error and mean absolute error.
In one embodiment of the invention, SPAD value appraising model by taking North China's summer corn as an example is provided really
Determine method:
(1) data acquire
Trial zone in the present embodiment is that China Water Resources & Hydropower Science Research Institute's water-saving irrigation of in June, 2017-September is tested
Study base, the base are located at 39 ° 37 ' of north latitude, and 116 ° 26 ' of east longitude, height above sea level 40.1m；The ground belongs to the semiarid continent in warm temperate zone
Property monsoon climate, Winter-Spring arid, summer it is rainy.540 ㎜ of many years average annual rainfall, 12.1 DEG C of temperature on average, mean wind speed
1.2m/s, frost-free period in year average out to 185d, annual water surface evaporation are suitable in 1800 ㎜ or more, sunshine-duration in year month 2600h
The growth of summer corn.
Experimental design is small precast unit test, and experiment casing specification is 1m × 0.75m × 1m.It is sandy loam for examination soil
Based on, it is sowing on June 15 168,2017 epoch for examination Summer Corn Varieties, setting strain, line-spacing are 25 ㎝, and planting density is
75000 plants/hm2, harvested in September 25th.Test sets 4 fertilizer treatments altogether, each dose is respectively 0,225,450,
675kg/hm2, i.e. N0, N1, N2, N3 processing, wherein N2 processing is normal Fertilization Level, respectively handles 3 repetitions.It is for examination fertilizer
(leaded wastewater 15% contains P for compound fertilizer2O5Amount 15% contains K2O amount 15%), urea (leaded wastewater 46%), wherein compound fertilizer is as base manure
It applies, urea is that top dressing is applied in jointing-tasseling stage, other management are the same as conventional high-yield field.
Within summer corn breeding time, select under fine, gentle breeze or calm condition, using U.S. Analytical
Spectral Devices (ASD) company Field-Spec HandHeld2 type hand-held field spectroradiometer monitors influences of plant crown light
Reflectivity is composed, wave band is 325~1075nm, is divided into 1nm, spectral resolution 3nm between spectrum sample, suitable time is daily
10:00-14:00.In measurement process, carrying out standard white plate correction in time, (standard white plate reflectivity is 1, therefore gained object
Spectrum is relative reflectance), in order to accurately measure next processing.When measurement sensor probe vertically downward, spectrometer visual field
Angle is 25 °, away from canopy top vertical height about 10~20cm.Every small precast unit is chosen 3 plants of corns and is measured, and arithmetic is then taken
Canopy spectra reflectivity of the average value as the small precast unit summer corn.
When being monitored to summer corn influences of plant crown SPAD value, SPAD value and chlorophyll content are positively correlated in significant, energy
Enough accurate expression chlorophyll contents.SPAD-502 type chlorophyll meter can pass through optical principle rapid survey under the lossless situation in field
Plant the relative amount of current object blade unit area chlorophyll, i.e. SPAD value.Therefore, SPAD- is used within summer corn breeding time
502 type chlorophyll meters are synchronous when measuring influences of plant crown hyper spectral reflectance to carry out the observation of SPAD value, in the sampling point of measurement spectrum
Place selects second and third piece leaf of Summer Corn Canopy expansion to measure, chooses in the middle part of leaf when measurement and avoid vein, each
2 SPAD values of sampling point random measurement, then each small precast unit measures 6 SPAD values altogether, takes its average value as the small-sized steaming
Seep the canopy chlorophyll test value of instrument.
Above-mentioned data sampling monitoring time are as follows: according to summer corn growth and development characteristics will be divided into the time of infertility jointing stage,
Four key developmental stages such as tasseling stage, pustulation period and maturity period select sunny, calm weather measurement one in each breeding time mid-term
Secondary Summer Corn Canopy spectral reflectivity and sampling determination its SPAD value.
(2) data process&analysis
Before carrying out data analysis, the processing software ViewSpec Pro6.2 carried using spectrometer is by the original of measurement
Spectroscopic data carries out resampling and exports, sampling interval 1nm.In order to reject the influence and raising of Soil Background, atmospheric scattering
The contrast of different Absorption Characteristics seeks first differential to original spectrum, and red side, the indigo plant of blade are extracted from the first derivative spectra
While, it is yellow while etc. parameters.In test, chosen respectively in summer corn jointing stage, tasseling stage, pustulation period and maturity period every small precast unit
Three plants of Summer Corn Canopy blades carry out spectrum and the measurement of SPAD value.
Analyze Summer Corn Canopy SPAD value and yield under different nitrogen amount applieds:
If Fig. 2 is that different amount of nitrogens handle lower summer corn influences of plant crown SPAD value with the changing rule of breeding time.From figure
As can be seen that in the entire breeding time of summer corn, big processing its SPAD value of amount of nitrogen is generally greater than the small processing of amount of nitrogen,
It is different up to the level of signifiance (p < 0.05) in jointing stage, tasseling stage and maturity period Summer Corn Canopy SPAD value difference.It is promoted with breeding time,
Under N1, N2 and N3 processing, the variation of summer corn influences of plant crown SPAD value parabolically shape reaches maximum value in the watery stage, it
Afterwards SPAD value with the gradually aging of crop it is on a declining curve.
Chlorophyll is that plant carries out photosynthetic primary pigments, and the content of chlorophyll will directly influence the light of summer corn
Ability to function is closed, and then influences the accumulation of crop dry matter, eventually affects crop yield, and nitrogen is the important of chlorophyll
Component, as the chlorophyll that amount of nitrogen increases synthesis is consequently increased.From figure 3, it can be seen that it is beautiful to increase the summer with amount of nitrogen
Rice yield increases, and it is 10.435t/hm that yield, which reaches maximum value, under N2 horizontal processing2, the yield when amount of nitrogen further increases
N3 such as is reduced instead to handle.It is indicated above that the rational application of fertilizer can promote corn growth, guarantee corn with high yield, while controlling excessive apply
Pollution of area source caused by fertilizer is conducive to agricultural production Sustainable and highly-efficient use.
Analyze the variation of Summer Corn Canopy spectral reflectivity:
Fig. 4 and Fig. 5 show that spectral reflectivity of the summer corn influences of plant crown in visible light region is lower, are since leaf is green
Element absorbs most feux rouges and purple light but reflection green light, makes chlorophyll that green be presented, and chlorophyll is inhaled in photosynthetic light
It plays the role of a nucleus in receipts, therefore its curve of spectrum is in the red spectral band in the green light band in the region 550nm or so and 690nm or so region
It is respectively formed a reflection peak and absorbs paddy；The reflectivity of spectrum steeply rises to form " red side " now between 690~750nm
As；In near infrared region by the in-built control of summer corn influences of plant crown, canopy spectra reflectivity performance is a high reflection
Area.
Summer corn influences of plant crown is illustrated in figure 4 in the spectral reflectivity indicatrix of different growing, with other fertilities
Phase is compared, and summer corn influences of plant crown spectral reflectivity is in maturity period highest；Jointing stage canopy is minimum in visible light wave range reflectivity,
And near infrared region reflectivity then highest, with the propulsion of breeding time, it is seen that optical band reflectivity gradually rises, near infrared band
Reflectivity gradually decreases, and near infrared band is reduced to minimum value in the watery stage, and pustulation period maximum canopy spectra reflectivity is only up to
31.15%.
Its different corresponding spectral reflectivity of the SPAD value of summer corn influences of plant crown is also variant, such as Fig. 5.In visible light wave
In segment limit, SPAD value is lower, and canopy spectra reflectivity is higher, gradually decreases with the increase of SPAD value, in SPAD value
Canopy spectra reflectivity is minimum when being up to 47.09；And in the near infrared region, between the processing of summer corn influences of plant crown spectral reflectivity
Changing rule is then in opposite trend, i.e., minimum in SPAD value as the increase influences of plant crown spectral reflectivity of SPAD value increases
Canopy spectra reflectivity is minimum when 33.66, but difference is smaller between processing.
Summer Corn Canopy SPAD value spectrum monitoring sensitive band is screened:
(1) Summer Corn Canopy Leaf reflectance and its first derivative spectra and chlorophyll relative content SPAD are carried out
Correlation analysis, as shown in Figure 6 and Figure 7.
Summer corn influences of plant crown spectral reflectivity carries out correlation analysis result (Fig. 6) with SPAD value and shows in visible region
Domain 500~675nm wave band, SPAD value and the correlation of canopy spectra reflectivity be not significant in the jointing stage, in tasseling stage in significant
It being positively correlated, related coefficient is and negatively correlated with the maturity period in the watery stage between 0.42~0.56, and related coefficient fluctuation is larger,
Maximum value is stablized near 640nm wave band, and respectively -0.49 and -0.36.In red light region 675~760nm wave band, correlation
Become being positively correlated from negative correlation, wherein the related coefficient in jointing stage, tasseling stage, pustulation period and maturity period respectively -0.05~
0.63, it fluctuates in the range of 0.38~0.67, -0.61~0.34, -0.50~0.01, jointing stage and tasseling stage correlation highest
Wave band in 760nm, and pustulation period and maturity period then reach maximum value in 700nm wave band.In near infrared band, related coefficient phase
To stabilization, as breeding time promotes, the related coefficient between the two is stable 0.62,0.68,0.33 and 0.16 respectively.Comprehensive all-wave
From the point of view of section, tasseling stage SPAD value and the correlation of canopy spectra reflectivity are most stable and higher, have practical guidance meaning to fertilising
Justice.In terms of the summer corn time of infertility, the related coefficient of the two is stablized in 500~675nm -0.40 or so, in red spectral band shape
It is located at 700nm at a trough, forms a wave crest near infrared band and be located at 760nm, related coefficient is respectively -0.50
With 0.02.
Such as the related coefficient that Fig. 7 is summer corn influences of plant crown the first derivative spectra and SPAD value, it can be seen that between the two
Related coefficient is totally higher than the related coefficient of original spectrum Yu SPAD value, this is because eliminating Soil Background during asking micro-
Etc. influence of the factors to spectral reflectivity.Related coefficient between blue and green light and near infrared band, the two is higher but unstable
It is fixed；In red spectral band, the two is positively correlated in 712~754nm, has relatively high and stable positive correlation, and related coefficient is steady
It is scheduled between 0.55~0.81.Comprehensive Correlation Summer Corn Canopy spectral reflectivity and its first derivative spectra are related to SPAD value
Property, the most sensitive wave band of summer corn influences of plant crown SPAD value be located at 550nm wave crest, 640nm, 690nm trough, 700nm, 712~
Between 754nm and 760nm wave band.
(2) multiple regression analysis is carried out to 325nm~1075nm spectral reflectivity and SPAD value, acquisition has compared with sensitive band
405nm, 408nm and 700nm.
According to above-mentioned analysis as a result, listing the green light (550nm) of summer corn visible light region, feux rouges (720nm), feature
Point wave band (640nm, 690nm and 760nm) and 405nm, 408nm and 700nm wave being selected according to stepwise discriminant analysis method
The related coefficient of section canopy spectra reflectivity, the first derivative spectra and SPAD value is shown in Table 1.The result shows that characteristic wave bands 405nm,
The canopy spectra reflectivity and the first derivative spectra and SPAD value of 408nm, 550nm, 640nm and 760nm are only in part breeding time
In extremely significant or significant correlation, most of correlation for giving birth to the period is all lower or even non-correlation；Tasseling stage, the pustulation period and
The time of infertility, the spectral reflectivity and SPAD value of characteristic wave bands 690nm, 700nm and 720nm reach significant or extremely significant phase
It closes；For the correlation of the first derivative spectra and SPAD value, 690nm in the watery stage, maturity period and the time of infertility up to significant related,
700nm only reaches extremely significant correlation in the watery stage, and 720nm reaches extremely significant correlation in other fertility periods in addition to the pustulation period.
To sum up, with the correlation of characteristic wave bands spectral reflectivity and the first derivative spectra and SPAD value it is up to respectively selection criteria, obtains
It obtains in the time of infertility using spectral reflectivity, the most sensitive wave band point of the first derivative spectra monitoring summer corn influences of plant crown SPAD value
It Wei not 700nm and 690nm.
The related coefficient of 1 summer corn influences of plant crown SPAD value of table and spectral reflectivity and its first derivative spectra
Note: * *-P < 0.01, *-P < 0.05, ---non-correlation
Determine Summer Corn Canopy SPAD value spectrum monitoring index:
The present embodiment is based on 73 current SPAD value spectrum monitoring indexes (table 2), by each Monitoring Index
Model calculation value and summer corn influences of plant crown SPAD value carry out correlation analysis and preferably go out 5 higher spectral indexes of related coefficient
Model is modeled, be respectively (SDr-SDb)/(SDr+SDb), MCARI//OSAVI, TCARI/OSAVI, SDr/SDb and
MTCI, particularly relevant coefficient are shown in Table 3.In jointing stage and tasseling stage, except MCARI//OSAVI and TCARI/OSAVI spectral index with
The correlation of SPAD value is not significant, other spectral indexes reach significant or extremely significant level, and (SDr-SDb)/(SDr+SDb)
Exponential dependence highest, related coefficient are respectively 0.545 and 0.667.In the watery stage and the time of infertility, all spectral indexes with
SPAD value reaches extremely significant correlation, wherein MTCI index correlation highest in the watery stage, and related coefficient is up to 0.701；It is giving birth to entirely
Educate the phase (SDr-SDb)/(SDr+SDb) exponential dependence highest, related coefficient is up to 0.697.In the maturity period, MCARI//OSAVI is removed
Spectral index reaches the level of signifiance, other indexes reach extremely significant level, and (SDr-SDb)/(SDr+SDb) index and SPAD
Value related coefficient is up to 0.868.
Comprehensively consider the correlation of each breeding time spectral index and SPAD value, (SDr-SDb)/(SDr+SDb) index exists
Entire breeding time reaches extremely significant correlation；In conjunction with Fig. 2, it is preced between the processing of jointing stage, tasseling stage and maturity period difference amount of nitrogen
Layer SPAD value significant difference, and tasseling stage be SPAD value monitor to fertilising with directive significance key developmental stages, and this three
The correlation of a breeding time spectral index (SDr-SDb)/(SDr+SDb) and SPAD value is also highest, so recommending light herein
Spectrum index (SDr-SDb)/(SDr+SDb) is used as optimum maize canopy SPAD value Monitoring Index.
2 SPAD value spectral index of table and calculation formula
3 summer corn influences of plant crown SPAD value of table and spectral correlation correlation of indices coefficient
Note: * *-P < 0.01, *-P < 0.05, ---non-correlation
(3) it determines and compares four Summer Corn Canopy SPAD value appraising models, obtain maximum likelihood estimation model:
Comprehensively consider result above, selection is reflected with the biggish 700nm original spectrum of SPAD value correlation in the present embodiment
Rate, 690nm the first derivative spectra, spectral index (SDr-SDb)/(SDr+SDb) and utilization Stepwise Discriminatory Analysis obtain optimal
Band combination etc. is constructed respectively based on original spectrum reflectivity, the first derivative spectra, spectral index and optimal bands composite
Summer corn influences of plant crown SPAD value estimation models are shown in Table 4, and use the coefficient of determination (R2), root-mean-square error (RMSE) and average exhausted
It tests to indexs such as errors (MAE) to model.When carrying out regression modeling, spectrum parameter variable is attempted respectively to refer to
Number, linear, logarithm, multinomial and power function model, and 700nm spectral reflectivity, 690nm the first derivative spectra and (SDr-
SDb)/(SDr+SDb) fitting of exponent pair SPAD value is all best with quadratic polynomial equation, and with spectral index (SDr-SDb)/
(SDr+SDb) calculated value is the observation of the appraising model of independent variable and the fit equation of predicted value is with maximum decision
Number 0.539, the smallest root-mean-square error 6.194 and the smallest mean absolute error 4.702；
It is established using the linear regression function that polynary Stepwise Discriminatory Analysis obtains band combination based on wave band optimum combination
Summer corn influences of plant crown SPAD value appraising model, the R between pattern die analog values and measured value2, RMSE, MAE be respectively
0.777,4.308,3.245.Comparison optimal bands composite and spectral index show based on the former structure the fitting effect of SPAD value
Its coefficient of determination of the model built R2Maximum, RMSE and MAE are minimum, model accuracy highest, are time of infertility the best-estimated model.
In addition, its testing accuracy is only second to best model with the quadratic polynomial model of (SDr-SDb)/(SDr+SDb) index construction.Cause
This, the linear regression appraising model y=45.262-376.843R700+ established based on 405nm, 408nm and 700nm band combination
8052.458R408-6901.352R405 can be used as the best-estimated model of summer corn influences of plant crown SPAD value.
The fitting of 4 summer corn time of infertility canopy SPAD value Spectral-parameter-model of table and verifying
(4) conclusion
It is tested with small precast unit to the lower summer corn influences of plant crown spectral reflectivity of different amount of nitrogens processing in the present embodiment
Research is monitored with SPAD value.By studying 4 key developmental stages influences of plant crown of summer corn in the reflectivity of 325~1025nm
Indicatrix finds that each breeding time spectral reflectivity indicatrix trend is consistent, in visible light wave range, canopy spectra reflectivity master
It to be influenced by chlorophyll, be promoted with breeding time, SPAD value is continuously increased, and leaf area increases, and Soil Background noise reduces, spectrum
Reflectivity constantly increases；The optical characteristics and canopy structure of leaf tissue, blade interior pair are depended mainly near infrared band
The multiple reflections of light and scattering form high reflection platform, and space between cells, shape, the difference of ingredient are to spectrum inside plant leaf blade
Reflection impacts.Different amount of nitrogens handle lower summer corn influences of plant crown SPAD value significant difference, and plant spectrum also shows phase
The variation answered.Influences of plant crown SPAD value and original spectrum and the first derivative spectra are all significant related, and SPAD value and first differential
The related coefficient of spectrum is totally higher than the related coefficient with original spectrum, this is because the first derivative spectra can effectively reduce
The influence of the factors such as Soil Background, thus sensitive band can be filtered out according to the variation of spectral reflectivity and the first derivative spectra
And optimal bands composite estimates the SPAD value of Summer Corn Canopy.
The wave band of summer corn plant time of infertility original spectrum and SPAD value correlation maximum is located at 700nm, first differential
The wavelength location of spectrum and SPAD value correlation maximum is 690nm, and related coefficient is respectively -0.498, -0.538, is reached aobvious
It is related.In 5 spectral indexes listed in embodiment, most of indexes are in significant phase with SPAD value in each breeding time
It closes, wherein (SDr-SDb)/(SDr+SDb) index is in each breeding time to SPAD value up to extremely significant related.
It is based respectively on original spectrum reflectivity, the first derivative spectra, spectral index and optimal bands composite and establishes the summer
The appraising model of maize canopy SPAD value.Wherein, the model established based on optimal bands composite is better than to be built based on spectral index
Secondly vertical model is the model established based on the first derivative spectra, and the models fitting effect based on original spectrum foundation is most
Difference, this combines the interference that can reduce the extraneous factors such as Soil Background with multiband, enhances Summer Corn Canopy precision of spectral information,
Enhance related with the correlation of Summer Corn Canopy SPAD value.
From above-described embodiment it can be concluded that
1) in visible light wave segment limit, with SPAD value increase spectral reflectance values reduce, near infrared band 760~
Within the scope of 1075nm, as SPAD value increases, spectral reflectance values increase.
2) in the summer corn time of infertility using original spectrum, the most sensitive wave band of the first derivative spectra monitoring canopy SPAD value
Respectively 700nm, 690nm；The optimal bands composite obtained by stepwise regression analysis is by 405nm, 408nm and 700nm wave band structure
At.
3) spectral index (SDr-SDb)/(SDr+SDb) reaches extremely significant related in each breeding time to SPAD value, related
For absolute coefficient 0.545 or more, versatility is higher.
4) beautiful in the summer established based on original spectrum reflectivity, the first derivative spectra, spectral index and optimal bands composite
In the regression model of rice SPAD value, 4 kinds of modeling effects are ranked up successively according to modeling precision are as follows: optimal wave
Duan Zuhe, spectral index, original spectrum reflectivity, the first derivative spectra；Thus, this research recommend based on 405nm, 408nm and
The linear regression appraising model y=45.262-376.843R700+8052.458R408- that 700nm band combination is established
6901.352R405 the best-estimated model as summer corn influences of plant crown SPAD value.
The invention has the benefit that the Summer Corn Canopy SPAD value appraising model provided by the invention based on EO-1 hyperion
Determine method, using summer corn as research object, field spectroradiometer is technical support in a handheld, to the different chlorophyll content lower summers
Maize canopy spectral signature is studied, and by the correlation between analysis Summer Corn Canopy SPAD value and photosphere spectrum, is determined
The spectrum sensitive wave band of Summer Corn Canopy SPAD value and optimal SPAD value appraising model.It is small in Summer Corn Canopy data monitoring
The test of type lysimeter, it is more accurate to hold to different parameters processing, and smaller, acquisition is interfered by various factors compared to field experiment
Data and the conclusion that obtains it is more accurate；It is studied in the method for the present invention for time of infertility Summer Corn Canopy, compared to single
One key developmental stages data modeling, time of infertility sample data is abundant, improves the reliability of appraising model；And compared to summer jade
Rice leaf scale research, canopy scale research conclusion are of great significance to areal study.
Claims (10)
1. a kind of determination method of the Summer Corn Canopy SPAD value appraising model based on EO-1 hyperion, which is characterized in that including following
Step:
S1, using small precast unit experimental cultivation summer corn, and monitor the original spectrum reflectivity and SPAD value of Summer Corn Canopy；
S2, resampling is carried out to original spectrum reflectivity and is exported, and determine its first derivative spectra；
S3, correlation analysis is carried out with original spectrum reflectivity and the first derivative spectra respectively to the SPAD value of Summer Corn Canopy,
Spectral band corresponding to determining original spectrum reflectivity and the first derivative spectra with summer corn SPAD value correlation maximum；
Spectral band corresponding to the original spectrum reflectivity and the first derivative spectra is respectively original spectrum reflectivity, single order
The most sensitive wave band of differential smoothing monitoring Summer Corn Canopy SPAD value；
S4, optimal bands composite is obtained by multivariate analysis in regressive to the most sensitive wave band of Summer Corn Canopy；
S5, the optimal spectral index of Summer Corn Canopy SPAD value is determined；
S6, be based respectively on the original spectrum reflectivity of SPAD value correlation maximum, the first derivative spectra, optimal bands composite and
Optimal spectral index establishes summer corn influences of plant crown SPAD value appraising model；
S7, it is tested by model-evaluation index to four summer corn influences of plant crown SPAD value appraising models, determines the optimal summer
Corn SPAD value appraising model.
2. the determination method of Summer Corn Canopy SPAD value appraising model according to claim 1, which is characterized in that the step
The method of Summer Corn Canopy original spectrum reflectivity is measured in rapid S1 specifically:
Summer Corn Canopy original spectrum reflectivity is monitored within summer corn breeding time by spectrometer, in monitoring process, is marked
Several plants of summer corns in each small precast unit are carried out spectral reflectivity monitoring, then by several light by quasi- blank correction
Original spectrum reflectivity of the arithmetic average of spectrum reflectivity as the Summer Corn Canopy of the small precast unit；
The monitoring parameters of the Summer Corn Canopy original spectrum reflectivity are arranged are as follows: spectral band is 325nm~1075nm, monitoring
Sampling interval is 1nm, spectral resolution 3nm, and monitoring time is daily 10 points~14 points, spectrometry sensor device probe vertical to
Under, spectrometer field angle is 25 °, is 10~20cm apart from Summer Corn Canopy top vertical height.
3. the determination method of Summer Corn Canopy SPAD value appraising model according to claim 1, which is characterized in that the step
The method of Summer Corn Canopy SPAD value is monitored in rapid S1 specifically:
Summer Corn Canopy SPAD value is monitored in summer corn breeding time by chlorophyll meter, by second and third of Summer Corn Canopy expansion
Blade chooses middle part of blade as monitoring sampling point, when monitoring and avoids vein, several SPAD values of each sampling point random measurement take
The average value of all SPAD values of same small precast unit is as small precast unit SPAD value.
4. the determination method of Summer Corn Canopy SPAD value appraising model according to claim 1, which is characterized in that the step
Rapid S2 specifically:
The original spectrum reflectivity data of monitoring is subjected to resampling by the processing software of spectrometer and is exported, to original spectrum
Reflectivity data seeks first differential, and extract from the first derivative spectra blade it is red while, it is blue while and yellow side parameter, be used for the summer
The SPAD value of maize canopy and the correlation analysis of the first derivative spectra；
Wherein, sampling interval 1nm.
5. the determination side of Summer Corn Canopy SPAD value appraising model described according to claim 1~3 any one claims
Method, which is characterized in that jointing stage, tasseling stage, pustulation period and maturity period in summer corn breeding time are both needed to seep in each small-sized steaming
The monitoring that several Summer Corn Canopies carry out original spectrum reflectivity and SPAD value is chosen in instrument.
6. the determination method of Summer Corn Canopy SPAD value appraising model according to claim 1, which is characterized in that the step
Rapid S3 specifically:
Calculate the related coefficient of Summer Corn Canopy SPAD value and original spectrum reflectivity and the first derivative spectra, determining and summer corn
Spectral band corresponding to the original spectrum reflectivity and the first derivative spectra of SPAD value correlation maximum；
The calculation formula of the correlation coefficient r are as follows:
In formula, n is actual measurement number；
xiFor the spectral reflectivity or the first derivative spectra of i-th of Summer Corn Canopy；
For the average value or the first derivative spectra average value of the spectral reflectivity of i-th of Summer Corn Canopy；
yiFor i-th of Summer Corn Canopy SPAD value；
For the average value of i-th of Summer Corn Canopy SPAD value.
7. the determination method of Summer Corn Canopy SPAD value appraising model according to claim 1, which is characterized in that the step
Rapid S4 specifically:
Using method of gradual regression, within the scope of Summer Corn Canopy 325nm~1075nm spectral reflectivity and SPAD value return
Return analysis, obtains the optimal bands composite of summer corn influences of plant crown.
8. the determination method of Summer Corn Canopy SPAD value appraising model according to claim 1, which is characterized in that the step
Rapid S5 specifically:
Based on 73 SPAD value spectral indexes, by each SPAD value spectrum monitoring index and summer corn influences of plant crown
SPAD value carries out correlation analysis and determines the optimal spectral index of Summer Corn Canopy according to its related coefficient.
9. the determination method of Summer Corn Canopy SPAD value appraising model according to claim 1, which is characterized in that the step
Four summer corn influences of plant crown SPAD value appraising models are quadratic term equation in rapid S6.
10. the determination method of Summer Corn Canopy SPAD value appraising model according to claim 1, which is characterized in that described
Evaluation index in step S7 is the coefficient of determination, root-mean-square error and mean absolute error.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810727612.9A CN109060676A (en) | 2018-07-05 | 2018-07-05 | Based on the determination method of the Summer Corn Canopy SPAD value appraising model of EO-1 hyperion |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810727612.9A CN109060676A (en) | 2018-07-05 | 2018-07-05 | Based on the determination method of the Summer Corn Canopy SPAD value appraising model of EO-1 hyperion |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN109060676A true CN109060676A (en) | 2018-12-21 |
Family
ID=64819156
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810727612.9A Pending CN109060676A (en) | 2018-07-05 | 2018-07-05 | Based on the determination method of the Summer Corn Canopy SPAD value appraising model of EO-1 hyperion |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109060676A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110082309A (en) * | 2019-05-20 | 2019-08-02 | 中国水利水电科学研究院 | Canopy of winter wheat SPAD value integrated spectral monitoring model method for building up |
| CN110567891A (en) * | 2019-09-16 | 2019-12-13 | 中国水利水电科学研究院 | Winter wheat canopy chlorophyll estimation system and method |
| CN112750048A (en) * | 2020-12-22 | 2021-05-04 | 中国农业大学 | Method for dynamically analyzing cereal crop canopy senescence progress by utilizing post-flowering NDVI |
| CN112945881A (en) * | 2021-03-11 | 2021-06-11 | 内蒙古农业大学 | Method for monitoring water content of potato leaves based on hyperspectral characteristic parameters |
| CN115144346A (en) * | 2022-06-23 | 2022-10-04 | 勐海曼香云天农业发展有限公司 | Method and system for determining field maturity of fragrant rice |
-
2018
- 2018-07-05 CN CN201810727612.9A patent/CN109060676A/en active Pending
Non-Patent Citations (2)
| Title |
|---|
| 刘秀英: "《玉米生理参数及农田土壤信息高光谱监测模型研究》", 《中国博士学位论文全文数据库》 * |
| 田永超 等: "《基于光谱信息的作物氮素营养无损监测技术》", 《生态学杂志》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110082309A (en) * | 2019-05-20 | 2019-08-02 | 中国水利水电科学研究院 | Canopy of winter wheat SPAD value integrated spectral monitoring model method for building up |
| CN110567891A (en) * | 2019-09-16 | 2019-12-13 | 中国水利水电科学研究院 | Winter wheat canopy chlorophyll estimation system and method |
| CN112750048A (en) * | 2020-12-22 | 2021-05-04 | 中国农业大学 | Method for dynamically analyzing cereal crop canopy senescence progress by utilizing post-flowering NDVI |
| CN112945881A (en) * | 2021-03-11 | 2021-06-11 | 内蒙古农业大学 | Method for monitoring water content of potato leaves based on hyperspectral characteristic parameters |
| CN112945881B (en) * | 2021-03-11 | 2022-10-25 | 内蒙古农业大学 | Method for monitoring water content of potato leaves based on hyperspectral characteristic parameters |
| CN115144346A (en) * | 2022-06-23 | 2022-10-04 | 勐海曼香云天农业发展有限公司 | Method and system for determining field maturity of fragrant rice |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107796764B (en) | Method for constructing wheat leaf area index estimation model based on three-band vegetation index | |
| CN109060676A (en) | Based on the determination method of the Summer Corn Canopy SPAD value appraising model of EO-1 hyperion | |
| Tian et al. | Comparison of different hyperspectral vegetation indices for canopy leaf nitrogen concentration estimation in rice | |
| CN109187441B (en) | Method for constructing summer corn nitrogen content monitoring model based on canopy spectral information | |
| CN110376167A (en) | Rice leaf nitrogen content monitoring method based on unmanned plane EO-1 hyperion | |
| Stroppiana et al. | Plant nitrogen concentration in paddy rice from field canopy hyperspectral radiometry | |
| CN102426153B (en) | A kind of Wheat plant moisture monitoring method based on canopy high spectral index | |
| CN107024439A (en) | A kind of paddy rice different growing chlorophyll content EO-1 hyperion estimating and measuring method | |
| CN103196838B (en) | Hyperspectral remote sensing monitoring method for coastal estuary eutrophication | |
| CN109187398A (en) | A kind of EO-1 hyperion measuring method of wheat plant nitrogen content | |
| CN107505271B (en) | Plant nitrogen estimation method and system based on nitrogen component radiation transmission model | |
| CN107271382A (en) | A kind of different growing rape leaf SPAD value remote sensing estimation methods | |
| Feng et al. | Analysis of the relationship between the spectral characteristics of maize canopy and leaf area index under drought stress | |
| CN103868880A (en) | Wheat leaf nitrogen content monitoring method based on spectrum double-peak index and method for establishing monitoring model | |
| CN103293111A (en) | Wheat leaf layer nitrogen content spectral monitoring mode under soil background interference and modeling method | |
| Song et al. | Using multi-angle hyperspectral data to monitor canopy leaf nitrogen content of wheat | |
| CN108520127A (en) | A kind of EO-1 hyperion inversion method of seeds leaf area index | |
| CN104502283A (en) | Two-band hyperspectral index and prediction model for estimating yield and shoot dry weight of soybean | |
| CN110082309B (en) | Method for establishing SPAD value comprehensive spectrum monitoring model of winter wheat canopy | |
| CN110069895B (en) | Method for establishing winter wheat nitrogen content full-growth period spectrum monitoring model | |
| Singh et al. | Quantification of leaf pigments in soybean (Glycine max (L.) Merr.) based on wavelet decomposition of hyperspectral features | |
| CN106485345A (en) | Cotton Gossypii time of infertility canopy SPAD value remote sensing appraising and appraising model construction method | |
| CN106469240A (en) | Rape leaf SPAD estimation based on spectral index and estimation models construction method | |
| Wen et al. | Estimation of the vertically integrated leaf nitrogen content in maize using canopy hyperspectral red edge parameters | |
| CN111044516A (en) | Remote sensing estimation method for chlorophyll content of rice |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20181221 |