CN-122004012-A - Rare earth mine soil seed bank screening and construction method based on ecological niche complementation

CN122004012ACN 122004012 ACN122004012 ACN 122004012ACN-122004012-A

Abstract

The invention discloses a rare earth mine soil seed bank screening and constructing method based on ecological niche complementation, which comprises the following steps of firstly preparing three types of soil matrixes, selecting candidate plants based on original community investigation results of an unexplored rare earth mine, selecting healthy seeds to be germinated in the candidate plants, obtaining germinated seedlings after germination and culture, planting the germinated seedlings or transplanted seedlings in the three types of soil matrixes, measuring biomass of the plants, measuring pH and nutrient content of the soil matrixes, screening resistant plants based on measured data, combining the screened resistant plants according to herbaceous, shrubs and vines based on an ecological niche complementation principle, and sowing the artificial seed bank in improved soil according to specific density. The resistance plants such as caragana microphylla screened by the method disclosed by the invention are strong in adaptability, the seed bank species is reasonable in structure, the vegetation coverage after restoration is close to the original ore vegetation coverage level, the mine soil restoration efficiency and the ecological stability are obviously improved, and the method has a good application prospect.

Inventors

LIU YIZHEN
YAO CHI
GE GANG
WU LAN
CAI QIYING
SHI YUE

Assignees

南昌大学

Dates

Publication Date: 20260512
Application Date: 20260403

Claims (9)

1. The rare earth mine soil seed bank screening and constructing method based on ecological niche complementation is characterized by comprising the following steps: s1, preparing three types of soil matrixes, namely a matrix 1, a matrix 2 and a matrix 3; s2, selecting herbaceous, shrubs and vine seedlings as candidate plants based on the original community investigation result of the unexplored rare earth mine; s3, selecting healthy seeds to be germinated in the candidate plants, pretreating, and then placing the healthy seeds in a phytotron for germination culture to obtain germinated seedlings; s4, respectively planting germinated seedlings or transplanted seedlings in three types of soil matrixes, controlling planting density and maintenance conditions, and observing and recording plant growth conditions and plant heights; S5, determining the aboveground biomass and the underground root biomass of the plants, and simultaneously determining the pH, total organic carbon TOC, total nitrogen TN, total phosphorus TP and aluminum concentration of three types of soil matrixes; s6, screening out resistant plants with acidification resistance and barren resistance based on the data measured in the S5; S7, based on an ecological niche complementation principle, combining the screened resistant plants according to herbs, shrubs and vines to construct an artificial seed bank; s8, uniformly sowing mixed seeds of the artificial seed bank on the surface of the improved rare earth mine soil, and covering the soil to finish vegetation restoration.
2. The method for screening and constructing the rare earth mine soil seed pool based on ecological niche complementation according to claim 1, wherein in S1, the matrix 1 is rare earth tailings after ammonium sulfate leaching, the matrix 2 is rare earth tailings after aluminum sulfate leaching for adjusting aluminum content, and the matrix 3 is an improved matrix formed by mixing the rare earth tailings after aluminum sulfate leaching for adjusting aluminum content with a soil restoration agent; The soil restoration agent is prepared from red and yellow soil, an organic fertilizer and an inorganic fertilizer according to the proportion of 80-100:10-20:1-5, wherein the organic fertilizer is chicken manure, duck manure, cake or biochar.
3. The method for screening and constructing rare earth mine soil seed banks based on ecological niche complementation according to claim 2, wherein in S2, candidate plants comprise cercospora canina, sumac, seabuckthorn, caragana microphylla, cymbidium faberi and cassia tora, and ecological niche complementation is ensured.
4. The rare earth mine soil seed bank screening and constructing method based on ecological niche complementation according to claim 3, wherein in S3, the candidate plants to be germinated comprise herba Canitis, rhus chinensis, fructus Hippophae, herba Caraganae Intermediae and herba Paederiae, and the pretreatment process is as follows: 100 seeds of each plant are selected, soaked in 0.5g/L KMnO4 solution for 24 hours, and washed at least 3 times with clean water; washing the culture dishes with sterile water, drying at high temperature for later use, filling a layer of wet absorbent cotton in each culture dish, uniformly sowing 20 seeds in each culture dish, wherein each plant comprises 5 culture dishes; Culturing in artificial climate culture room under the conditions of 25deg.C, 60% humidity and 20% illuminance, alternately every 12 hr; And spraying a proper amount of distilled water on each culture dish every day during germination, observing and recording seed germination conditions, and obtaining germinated seedlings.
5. The rare earth mine soil seed bank screening and constructing method based on ecological niche complementation according to claim 4, wherein the step S4 is specifically as follows: Planting germinated seedlings or transplanted seedlings in three types of soil matrixes respectively, and planting 5 pots of each plant under each soil matrix by adopting square flowerpots with the length of 7cm multiplied by 7.5 cm; Wherein, the planting density of the herba et Gemma Agrimoniae, the caragana microphylla, the herba Paederiae, the Rhus chinensis, the sea buckthorn and the Cassia bifolia is 5 plants planted in a scattered manner in each pot; And (3) watering 1 time every 1 day during the plant growth maintenance period, and observing and recording the plant growth condition and plant height.
6. The method for screening and constructing rare earth mine soil seed bank based on ecological niche complementation according to claim 5, wherein in S5, the process for measuring the above-ground biomass and the below-ground root biomass of the plant is as follows: respectively harvesting survival plants from the three types of soil matrixes, and filling each plant into a self-sealing bag; After being washed cleanly, the overground part and the root system of each plant are separated and are placed in a drying box for drying for 24 hours; The dry weight of the overground part and the root system of each plant under three types of soil matrixes is measured by an analytical balance, so that the overground biomass and the underground root system biomass are characterized.
7. The method for screening and constructing the rare earth mine soil seed bank based on ecological niche complementation according to claim 6, wherein in S5, the soil for planting each plant under three types of soil matrixes is collected, spread on clean paper, spread into thin layers and naturally air-dried; When the pH value of the soil is measured, mixing the soil with boiled and cooled distilled water according to the mass-volume ratio of 2:5, oscillating for 2min, centrifuging for 10min at the maximum rotation speed of a centrifugal machine, measuring the pH value of the supernatant by a pH meter, and recording; when the TOC of the total organic carbon is measured, a potassium dichromate-sulfuric acid oxidation method is combined with a ferrous sulfate titration method for measurement; After the total nitrogen TN and the total phosphorus TP are digested with concentrated sulfuric acid and perchloric acid, the total nitrogen TN and the total phosphorus TP are measured by a chemical batch analyzer.
8. The method for screening and constructing rare earth mine soil seed banks based on ecological niche complementation according to claim 7, wherein in S6, based on the data measured in S5, resistant plants with acidification resistance and barren resistance are screened according to the survival state of plants, biomass accumulation and adaptability to soil environment, and the screening criteria of the resistant plants are as follows: plants that survive in matrix 1 or matrix 2 and increase soil pH, total organic carbon TOC, total nitrogen TN, total phosphorus TP content.
9. The method for screening and constructing a rare earth mine soil seed bank based on ecological niche complementation according to claim 8, wherein in S7, constructed artificial seed banks comprise shrubs, herbs and vines; the shrubs comprise sisal hemp, herba Duchesneae Indicae, caragana microphylla, semen Cassiae, fructus Ricini and Rhus chinensis, the herbs comprise herba Paederiae, vetiver grass, mango, herba Canitis, ryegrass, dandelion, flos Chrysanthemi Indici, flos Boschniakiae Rossicae and radix et caulis Opuntiae Dillenii, and the vine is kudzu.

Description

Rare earth mine soil seed bank screening and construction method based on ecological niche complementation Technical Field The invention relates to the technical field of mine ecological restoration, in particular to a rare earth mine soil seed bank screening and constructing method based on ecological niche complementation. Background In the mineral leaching process of the ion type rare earth mine, the physical and chemical properties of the soil can be changed drastically, and the ion type rare earth mine is characterized in that vegetation is cleared, pH of the soil is obviously reduced, acidification is aggravated, the content of soil nutrients such as TOC, TP and the like is extremely low, and a soil seed warehouse is lacked. The severe soil environment seriously hinders plant growth, so that vegetation in a mine area is degenerated, bare land is increased, and an ecological system is destroyed. In the existing mine soil restoration technology, plant restoration is widely applied due to low cost and environmental friendliness, but the defects that candidate plants lack targeted screening, special environments with acidification of mine soil and extremely low nutrients are not fully considered, so that the plant survival rate is low, natural restoration of mine abandoned lands lacks natural seed banks, continuous stable vegetation restoration seed sources are difficult to form, the seed banks are single in species and are not combined according to an ecological niche complementation principle, the vegetation coverage speed is low, the stability is poor, the seed banks are required to be constructed manually to form continuous vegetation restoration seed sources, and soil improvement and plant screening are disjointed, so that collaborative promotion of soil environment improvement and vegetation restoration is difficult to realize. Therefore, a method for screening the ion type rare earth mine soil seed bank with strong pertinence and good restoration effect is needed. Disclosure of Invention The invention aims to provide a rare earth mine soil seed bank screening and constructing method based on ecological niche complementation, which realizes the accurate screening of acid-resistant and aluminum-resistant plants, and the vegetation coverage of ion type rare earth mine soil is rapidly improved by constructing an artificial seed bank with reasonable structure and high stability, so as to realize the effective recovery of a soil ecosystem. In order to achieve the purpose, the invention provides a rare earth mine soil seed bank screening and constructing method based on ecological niche complementation, which comprises the following steps: s1, preparing three types of soil matrixes, namely a matrix 1, a matrix 2 and a matrix 3; s2, selecting herbaceous, shrubs and vine seedlings as candidate plants based on the original community investigation result of the unexplored rare earth mine; s3, selecting healthy seeds to be germinated in the candidate plants, pretreating, and then placing the healthy seeds in a phytotron for germination culture to obtain germinated seedlings; s4, respectively planting germinated seedlings or transplanted seedlings in three types of soil matrixes, controlling planting density and maintenance conditions, and observing and recording plant growth conditions and plant heights; S5, determining the aboveground biomass and the underground root biomass of the plants, and simultaneously determining the pH, total organic carbon TOC, total nitrogen TN, total phosphorus TP and aluminum concentration of three types of soil matrixes; s6, screening out resistant plants with acidification resistance and barren resistance based on the data measured in the S5; S7, based on an ecological niche complementation principle, combining the screened resistant plants according to herbs, shrubs and vines to construct an artificial seed bank; s8, uniformly sowing mixed seeds of the artificial seed bank on the surface of the improved rare earth mine soil, and covering the soil to finish vegetation restoration. Preferably, in S1, the matrix 1 is rare earth tailings after the ammonium sulfate leaching, the matrix 2 is rare earth tailings with aluminum content adjusted after the aluminum sulfate leaching, and the matrix 3 is an improved matrix obtained by mixing the rare earth tailings with the aluminum content adjusted after the aluminum sulfate leaching with a soil restoration agent; The soil restoration agent is prepared from red and yellow soil, an organic fertilizer and an inorganic fertilizer according to the proportion of 80-100:10-20:1-5, wherein the organic fertilizer is chicken manure, duck manure, cake or biochar. Preferably, in S2, the candidate plants include cercospora, sumac, seabuckthorn, caragana microphylla, sargent gloryvine and cassia bifascus, ensuring ecological potential difference complementation. Preferably, in S3, the candidate plants to be germinated include Sedum sarmentosum, rhus ch