Method for improving site conditions of inefficient forest

Abstract

The invention discloses a method for improving the site condition of a low-efficiency forest, which comprises the following steps: accurately improving the site condition of the low-efficiency forest by improving the physical property of soil, the moisture condition of soil, the nutrient condition of soil, the chemical property of soil, the microclimate condition, the biological competition condition and the like. The problems of soil hardening, poor permeability, low water holding capacity, shallow and thin soil layer, excessive gravels and serious erosion are effectively solved; drought, water shortage, seasonal waterlogging and over-high or over-low underground water level; the soil is barren, lacks necessary nutrient elements such as nitrogen, phosphorus and potassium, and is low in organic matter content; soil is over-acid, over-alkali, salinization, heavy metal pollution and the like; extreme high temperature / low temperature, strong wind, frost and strong illumination; weeds, shrubs or non-target tree species fiercely compete with target tree species for illumination, moisture, nutrients and the like, and the site conditions of forest growth are remarkably improved, so that healthy growth of forests is promoted.

Description

Technical Field

[0001] The invention relates to the technical field of improving site conditions in forest management, and in particular to a method for improving site conditions in low-efficiency forests. Background Art

[0002] Modifying forest site conditions means improving or adjusting environmental factors that affect forest growth and development through human intervention measures, making them more conducive to the growth of target tree species, improving forest productivity, enhancing ecological functions or achieving specific management goals.

[0003] Forest site conditions (soil, topography, hydrology, climate, etc.) are key factors in determining forest productivity. When site conditions are poor, tree growth is stunted, ecosystem function is impaired, and improvement efforts face numerous challenges.

[0004] Currently, forests face challenges such as compacted soil, poor permeability, low water-holding capacity, shallow soil layers, excessive gravel, and severe erosion; drought and water shortages, seasonal waterlogging, and excessively high or low groundwater levels; poor soils lacking essential nutrients like nitrogen, phosphorus, and potassium, and low in organic matter; excessively acidic or alkaline soils, salinization, and heavy metal contamination; extreme temperatures, strong winds, frost, and intense sunlight; and fierce competition for light, water, and nutrients between weeds, shrubs, and non-target tree species and target species. Measures such as soil addition, fertilization, irrigation, and large-scale engineering projects often require significant investment, making them unsustainable outside of economic forests or specific ecological restoration projects. Short-term measures may lack long-term effects, and excessive intervention can disrupt the original ecological balance.

[0005] Existing technologies and methods for improving site conditions are unable to effectively solve the above-mentioned series of problems, which seriously hinders the growth of trees in forest land. Therefore, it is necessary to provide a method for improving site conditions of low-efficiency forests to solve the above-mentioned technical problems. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for improving the site conditions of low-efficiency forests, so as to solve the problem that in traditional methods of tending and transforming low-efficiency forests to improve site conditions, changing the site conditions is difficult, the methods are not in place and thorough, and some trees grow poorly due to soil compaction and lack of fertilizer.

[0007] The present invention has established a unique method for improving soil physical properties, soil moisture conditions, soil nutrient conditions, soil chemical properties, microclimate conditions, biological competition conditions, etc., which has achieved effective improvement of forest soil and provided strong support for the healthy growth of trees.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a method for improving site conditions of low-efficiency forests, comprising the following steps: (1) Improve the physical properties of the soil: This is usually done in autumn and winter. For local land preparation, use pit-shaped land preparation (digging planting holes), block-shaped land preparation, and fish-scale pit land preparation (water storage and soil conservation). For comprehensive land preparation, reclaim the entire afforestation land, which is prone to soil erosion and is suitable for flat areas without erosion risks. For forest land preparation, properly clear the ditches and level the soil in local low-lying and waterlogged forest land, and reclaim the forest land once. Deeply plow and loosen the soil. Apply organic fertilizers such as compost, green manure, and animal manure. Chop the remaining materials and spread them flat on the spot; (2) Improve soil moisture conditions: Water retention: Reduce soil moisture evaporation and increase rainwater retention through land preparation (fish-scale pits, horizontal ditches), mulching with mulch, straw, gravel, and the application of water-retaining agents. Irrigation and drainage. Select drought-resistant / waterlogging-tolerant tree species: Although not a direct site modification, it is also an important strategy for adapting to water conditions. (3) Improve soil nutrient status: apply base fertilizer, and apply organic fertilizer (compost, manure, green manure) or slow-release chemical fertilizer into the planting hole when replanting. Topdressing: apply quick-acting chemical fertilizer or spray foliar fertilizer during the critical growth period of the trees. Apply 1 kg of compound fertilizer to each remaining tree after felling. Plant green manure plants. Litter management: protect the litter layer on the forest floor, allow it to decompose naturally and return nutrients, and avoid excessive cleaning. Microbial fertilizer / mycorrhizal inoculation: inoculate nitrogen-fixing bacteria, phosphate-solubilizing bacteria, potassium-solubilizing bacteria or ectomycorrhizal fungi to help the trees absorb nutrients; (4) Improve soil chemical properties: Acidic soil: Apply alkaline substances such as lime and limestone powder to neutralize the acidity. Alkaline soil: Apply sulfur powder, gypsum, acidic fertilizers (such as ammonium sulfate) or organic fertilizers to lower the pH; Take measures to improve saline-alkali soil; (5) Improve microclimate conditions: Create shelterbelts / forest networks to reduce wind speed and regulate temperature and humidity. Retain or plant shade plants: Use shrubs or retain some native vegetation to provide lateral shade for seedlings in the early stages of afforestation to avoid direct sunlight and high temperature burns, especially on dry sunny slopes. Covering: Ground coverings such as straw and mulch can regulate ground temperature and reduce water evaporation; (6) Improve biological competition: Brush cutting and weeding: Manual or mechanical removal of competing vegetation around the afforestation hole or within the planting belt. Biological control: Use grazing cattle, sheep, etc. or specific plants to suppress weeds. Reasonable density planting: Through reasonable density planting, the target tree species will occupy the growing space as soon as possible to suppress weeds.

[0009] Preferably, in step (1), deep tillage refers to breaking up the plow bottom layer or compacted layer to increase soil porosity and air and water permeability, with a depth of up to 30-50 cm. The replacement soil refers to replacing part of the inferior soil (such as the gravel layer or the topsoil of heavily saline-alkali land) with fertile soil to increase the thickness of the soil layer.

[0010] Preferably, in step (1), the shredding of the tending residues and then spreading them on the spot refers to manually shredding the tending weeds, shrubs, vines and other residues and then spreading them on the spot, thereby increasing the amount of humus in the forest, improving the soil organic matter content, increasing soil nutrients and improving soil fertility, and improving the aggregate structure. However, it should be noted that the thickness of the blanket should not be too thick, generally not exceeding 5 cm, in order to accelerate the growth of the tree root system.

[0011] Preferably, in step (2), the irrigation is carried out by diverting water to the shelterbelts and intensively managed timber and economic forests that have irrigation conditions. The irrigation time is in early spring before sap flow, during the growing season, and during the dry season. The drainage is carried out by digging drainage ditches and underground pipes in low-lying waterlogged areas to lower the groundwater level and remove excess water.

[0012] Preferably, in step (3), the planting of green manure plants refers to planting nitrogen-fixing plants such as alfalfa and Lespedeza, etc., of the Leguminosae family before afforestation or in the forest, and turning and pressing them into the soil to increase organic matter and nitrogen.

[0013] Preferably, in step (4), the saline-alkali soil improvement measures include: 1) water conservancy projects: constructing drainage systems to divert fresh water to wash away salt; 2) chemical improvement: applying gypsum, phosphogypsum, etc. to replace sodium ions in the soil; 3) biological improvement: planting salt-tolerant pioneer plants such as Tamarix and Elaeagnus angustifolia to absorb salt or improve soil structure; 4) mulching to inhibit salt: covering the ground to reduce evaporation and return of salt; 5) contaminated soil remediation: adopting physical (soil import, leaching), chemical (passivation agents), biological (hyperaccumulators) and other methods depending on the type and degree of contamination.

[0014] Compared with the prior art, the present invention has the following beneficial effects: The method for improving site conditions of low-efficiency forests proposed in the present invention has many significant beneficial effects: 1. The present invention begins with improving the physical properties of the soil: this is generally carried out in autumn and winter. For local land preparation, pit-shaped land preparation (digging planting holes), block-shaped land preparation, and fish-scale pit-shaped land preparation (water storage and soil conservation) are used. For comprehensive land preparation, the entire afforestation land is reclaimed. This requires caution as it can easily cause soil erosion and is suitable for flat areas without erosion risks. For forest land preparation, appropriate ditch clearing and soil leveling are carried out in low-lying and waterlogged forest land, and the forest land is reclaimed once. Deep plowing and loosening the soil breaks up the plow bottom layer or compacted layer, increases soil porosity and air and water permeability, and can reach a depth of 30-50 cm. For imported soil, replace part of the poor-quality soil with fertile soil (such as replacing the gravel layer or the topsoil in heavily saline-alkali land). Increase the thickness of the soil layer. Apply organic materials such as compost, green manure, and animal manure. After tending, weeds, shrubs, vines, and other leftovers are manually chopped and spread flat on the ground. This increases the amount of humus in the forest, improves the soil organic matter content, increases soil nutrients and fertility, and improves the aggregate structure. However, care should be taken not to over-thicken the blanket, generally no more than 5cm. The purpose is to accelerate the growth of tree roots. 2. The present invention improves soil moisture conditions by: storing water and conserving moisture: reducing soil moisture evaporation and increasing rainwater retention through land preparation (fish-scale pits, horizontal ditches), covering with mulch, straw, gravel, and applying water-retaining agents. Irrigation: water should be diverted for irrigation in shelterbelts and intensively managed timber and economic forests that have irrigation conditions. The best time for irrigation is in early spring before the sap flows, during the growing season, and during the dry season. Drainage: digging drainage ditches and underground pipes in low-lying waterlogged areas to lower the groundwater level and remove excess water. Selecting drought-resistant / waterlogging-resistant tree species: Although it is not a direct site transformation, it is also an important strategy for adapting to moisture conditions; 3. The present invention starts by improving the soil nutrient status: improving the nutrient factors that limit the growth of trees, accelerating the growth of trees, shortening the rotation period or improving the quality of wood. First, apply base fertilizer: apply organic fertilizer (compost, manure, green manure) or slow-release chemical fertilizer in the planting hole when replanting. Topdressing: apply quick-acting chemical fertilizer or spray foliar fertilizer during the critical growth period of trees. After felling, apply 1 kg of compound fertilizer to each retained tree. Planting green manure plants: plant nitrogen-fixing plants such as alfalfa and Lespedeza in the Leguminosae family before afforestation or in the forest, and turn them into the soil to increase organic matter and nitrogen. Litter management: protect the litter layer on the forest land, allow it to decompose naturally and return nutrients, and avoid excessive cleaning. Microbial fertilizer / mycorrhizal inoculation: inoculate nitrogen-fixing bacteria, phosphate-solubilizing bacteria, potassium-solubilizing bacteria or ectomycorrhizal fungi to help trees absorb nutrients; 4. The present invention improves the chemical properties of the soil: Acidic soil: Apply alkaline substances such as lime and limestone powder to neutralize the acidity. Alkaline soil: Apply sulfur powder, gypsum, acidic fertilizers (such as ammonium sulfate) or organic fertilizers to lower the pH.

[0015] Improvement of saline-alkali soils: 1) Water conservancy projects: Build drainage systems to divert freshwater to wash away salt. 2) Chemical improvement: Apply gypsum, phosphogypsum, and other materials to replace sodium ions in the soil. 3) Biological improvement: Plant salt-tolerant pioneer plants such as Tamarix and Elaeagnus angustifolia to absorb salt or improve soil structure. 4) Mulching to inhibit salt: Cover the ground to reduce evaporation and return of salt. 5) Remediation of contaminated soil: Depending on the type and severity of contamination, physical (soil addition, leaching), chemical (passivation agents), and biological (hyperaccumulators) methods may be used. 5. This invention improves microclimate conditions by creating shelterbelts / forest networks, reducing wind speed and regulating temperature and humidity. It also preserves or plants shade plants: in the early stages of afforestation, shrubs or some native vegetation are retained to provide lateral shade for seedlings, protecting them from direct sunlight and high-temperature burns, especially on dry, sunny slopes. Ground cover: straw, mulch, and other ground cover can regulate ground temperature and reduce water evaporation. This adapts to climate change or specific needs, such as enhancing a forest's drought resistance, water conservation, or carbon sequestration capacity. 6. This invention improves biological competition by creating an environment conducive to competition and stable growth of target tree species, such as controlling excessive weed competition. This restores the functions of degraded ecosystems. Brush cutting and weeding: Manual or mechanical removal of competing vegetation around the planting site or within the planting belt. Biological control: Grazing cattle, sheep, or specific plants are used to suppress weeds. Appropriate planting density: This allows target tree species to quickly occupy their growing space and suppress weeds. DETAILED DESCRIPTION

[0016] The technical solutions of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0017] Example 1: This example provides a method for improving site conditions of low-efficiency forests, comprising the following steps: (1) Improve the physical properties of the soil: This is usually done in autumn and winter. For local land preparation, use pit-shaped land preparation (digging planting holes), block-shaped land preparation, and fish-scale pit land preparation (water storage and soil conservation). For comprehensive land preparation, reclaim the entire afforestation land, which is prone to soil erosion and is suitable for flat areas without erosion risks. For forest land preparation, properly clear the ditches and level the soil in local low-lying and waterlogged forest land, and reclaim the forest land once. Deeply plow and loosen the soil. Apply organic fertilizers such as compost, green manure, and animal manure. Chop the remaining materials and spread them flat on the spot; (2) Improve soil moisture conditions: Water retention: Reduce soil moisture evaporation and increase rainwater retention through land preparation (fish-scale pits, horizontal ditches), mulching with mulch, straw, gravel, and the application of water-retaining agents. Irrigation and drainage. Select drought-resistant / waterlogging-tolerant tree species: Although not a direct site modification, it is also an important strategy for adapting to water conditions. (3) Improve soil nutrient status: apply base fertilizer, and apply organic fertilizer (compost, manure, green manure) or slow-release chemical fertilizer into the planting hole when replanting. Topdressing: apply quick-acting chemical fertilizer or spray foliar fertilizer during the critical growth period of the trees. Apply 1 kg of compound fertilizer to each remaining tree after felling. Plant green manure plants. Litter management: protect the litter layer on the forest floor, allow it to decompose naturally and return nutrients, and avoid excessive cleaning. Microbial fertilizer / mycorrhizal inoculation: inoculate nitrogen-fixing bacteria, phosphate-solubilizing bacteria, potassium-solubilizing bacteria or ectomycorrhizal fungi to help the trees absorb nutrients; (4) Improve soil chemical properties: Acidic soil: Apply alkaline substances such as lime and limestone powder to neutralize the acidity. Alkaline soil: Apply sulfur powder, gypsum, acidic fertilizers (such as ammonium sulfate) or organic fertilizers to lower the pH.

[0018] Take measures to improve saline-alkali soil; (5) Improve microclimate conditions: Create shelterbelts / forest networks to reduce wind speed and regulate temperature and humidity. Retain or plant shade plants: Use shrubs or retain some native vegetation to provide lateral shade for seedlings in the early stages of afforestation to avoid direct sunlight and high temperature burns, especially on dry sunny slopes. Covering: Ground coverings such as straw and mulch can regulate ground temperature and reduce water evaporation; (6) Improve biological competition: Brush cutting and weeding: Manual or mechanical removal of competing vegetation around the afforestation hole or within the planting belt. Biological control: Use grazing cattle, sheep, etc. or specific plants to suppress weeds. Reasonable density planting: Through reasonable density planting, the target tree species will occupy the growing space as soon as possible to suppress weeds.

[0019] More specifically, in step (1), deep tillage refers to breaking up the plow bottom layer or compacted layer to increase soil porosity and air and water permeability, with a depth of up to 30-50 cm. The imported soil refers to replacing part of the inferior soil (e.g., replacing the gravel layer or the topsoil of heavily saline-alkali land) with fertile soil to increase the thickness of the soil layer.

[0020] More specifically, in step (1), the shredding of the remaining tending material refers to manually shredding the remaining weeds, shrubs, vines, etc. after tending and then spreading them on the spot, thereby increasing the amount of humus in the forest, improving the content of soil organic matter, increasing soil nutrients and fertility, and improving the aggregate structure. However, it should be noted that the thickness of the blanket should not be too thick, generally not exceeding 5 cm, in order to accelerate the growth of the tree root system.

[0021] More specifically, in step (2), the irrigation is carried out by diverting water to the shelterbelts and intensively managed timber and economic forests that have irrigation conditions. The irrigation time is in early spring before the sap flows, during the growing season, and during the dry season. The drainage is carried out by digging drainage ditches and underground pipes in low-lying waterlogged areas to lower the groundwater level and remove excess water.

[0022] More specifically, in step (3), the planting of green manure plants refers to planting nitrogen-fixing plants such as alfalfa and Lespedeza, etc., of the Leguminosae family before afforestation or in the forest, and turning and pressing them into the soil to increase organic matter and nitrogen.

[0023] More specifically, in step (4), the measures to improve saline-alkali soil include: 1) water conservancy projects: constructing drainage systems to divert fresh water to wash away salt; 2) chemical improvement: applying gypsum, phosphogypsum, etc. to replace sodium ions in the soil; 3) biological improvement: planting salt-tolerant pioneer plants such as Tamarix and Elaeagnus angustifolia to absorb salt or improve soil structure; 4) mulching to inhibit salt: covering the ground to reduce evaporation and return of salt; and 5) contaminated soil remediation: adopting physical (soil import, leaching), chemical (passivation agents), biological (hyperaccumulators) and other methods depending on the type and extent of contamination.

[0024] Example 2: Forest stand reconstruction in arid and semi-arid areas: fish scale pit / horizontal ditch land preparation + film mulching / grass mulching + water retaining agent + drought-resistant tree species.

[0025] Example 3: Transformation of forest stands on rocky mountainous land: blasting or artificial hole drilling + soil addition + application of organic fertilizer.

[0026] Example 4: Reconstruction of saline-alkali tidal flat forest stands: construction of drainage system + fresh water washing of salt + raising of planting surface with imported soil + application of amendments such as gypsum + salt-tolerant tree species.

[0027] Example 5: Forest reconstruction in felled areas: clean up felling residues, avoid fire + moderate land preparation, such as block land preparation + protect native seedlings and saplings.

[0028] In general, forest site modification is a highly technical undertaking requiring meticulous planning. Its core lies in diagnosing limiting factors and applying a combination of physical, chemical, biological, and engineering approaches to purposefully improve the environmental foundation for forest growth, thereby creating favorable conditions for healthy, efficient, and sustainable forest management.

[0029] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations that come within the meaning and range of equivalents of the claims be embraced therein.

Claims

1. A method for improving site conditions of low-efficiency forests, characterized in that: The following steps are involved: (1) Improve the physical properties of the soil: This is usually done in autumn and winter. For local land preparation, use pit-shaped land preparation (digging planting holes), block-shaped land preparation, and fish-scale pit land preparation (water storage and soil conservation). For comprehensive land preparation, reclaim the entire afforestation land, which is prone to soil erosion and is suitable for flat areas without erosion risks. For forest land preparation, properly clear the ditches and level the soil in local low-lying and waterlogged forest land, and reclaim the forest land once. Deeply plow and loosen the soil. Apply organic fertilizers such as compost, green manure, and animal manure. Chop the remaining materials and spread them flat on the spot; (2) Improve soil moisture conditions: Water retention: Reduce soil moisture evaporation and increase rainwater retention through land preparation (fish-scale pits, horizontal ditches), mulching with mulch, straw, gravel, and the application of water-retaining agents. Irrigation and drainage. Select drought-resistant / waterlogging-tolerant tree species: Although not a direct site modification, it is also an important strategy for adapting to water conditions. (3) Improve soil nutrient status: apply base fertilizer, and apply organic fertilizer (compost, manure, green manure) or slow-release chemical fertilizer into the planting hole when replanting. Topdressing: apply quick-acting chemical fertilizer or spray foliar fertilizer during the critical growth period of the trees. Apply 1 kg of compound fertilizer to each remaining tree after felling. Plant green manure plants. Litter management: protect the litter layer on the forest floor, allow it to decompose naturally and return nutrients, and avoid excessive cleaning. Microbial fertilizer / mycorrhizal inoculation: inoculate nitrogen-fixing bacteria, phosphate-solubilizing bacteria, potassium-solubilizing bacteria or ectomycorrhizal fungi to help the trees absorb nutrients; (4) Improve soil chemical properties: Acidic soil: Apply alkaline substances such as lime and limestone powder to neutralize the acidity. Soil: Apply sulfur powder, gypsum, acidic fertilizers (such as ammonium sulfate) or organic fertilizers to lower the pH; Take measures to improve saline-alkali soil; (5) Improve microclimate conditions: Create shelterbelts / forest networks to reduce wind speed and regulate temperature and humidity. Retain or plant shade plants: Use shrubs or retain some native vegetation to provide lateral shade for seedlings in the early stages of afforestation to avoid direct sunlight and high temperature burns, especially on dry sunny slopes. Covering: Ground coverings such as straw and mulch can regulate ground temperature and reduce water evaporation; (6) Improve biological competition: Brush cutting and weeding: Manual or mechanical removal of competing vegetation around the afforestation hole or within the planting belt. Biological control: Use grazing cattle, sheep, etc. or specific plants to suppress weeds. Reasonable density planting: Through reasonable density planting, the target tree species will occupy the growing space as soon as possible to suppress weeds.

2. The method for improving site conditions of low-efficiency forests according to claim 1, characterized in that: In step (1), deep plowing refers to breaking up the plow bottom layer or compacted layer to increase soil porosity and air and water permeability, with a depth of up to 30-50 cm. The imported soil refers to replacing part of the inferior soil (such as the gravel layer or the topsoil of heavy saline-alkali land) with fertile soil to increase the thickness of the soil layer.

3. The method for improving site conditions of low-efficiency forests according to claim 1, characterized in that: In step (1), the shredding of the remaining tending material refers to manually shredding the remaining weeds, shrubs, vines, etc. after tending and then spreading them on the spot, thereby increasing the amount of humus in the forest, improving the content of soil organic matter, increasing soil nutrients and fertility, and improving the aggregate structure. However, it should be noted that the thickness of the blanket should not be too thick, generally not exceeding 5 cm, in order to accelerate the growth of the tree root system.

4. The method for improving site conditions of low-efficiency forests according to claim 1, characterized in that: In step (2), the irrigation is carried out by diverting water to the shelterbelts and intensively managed timber and economic forests that have irrigation conditions. The irrigation time is in early spring before the sap flows, during the growing season, and during the dry season. The drainage is carried out by digging drainage ditches and underground pipes in low-lying waterlogged areas to lower the groundwater level and remove excess water.

5. The method for improving site conditions of low-efficiency forests according to claim 1, characterized in that: In the step (3), the planting of green manure plants refers to planting nitrogen-fixing plants such as alfalfa and Lespedeza, etc., of the Leguminosae family before afforestation or in the forest, and turning and pressing them into the soil to increase organic matter and nitrogen.

6. The method for improving site conditions of low-efficiency forests according to claim 1, characterized in that: In step (4), the measures to improve saline-alkali soil include: 1) water conservancy projects: constructing drainage systems to divert fresh water to wash away salt; 2) chemical improvement: applying gypsum, phosphogypsum, etc. to replace sodium ions in the soil; 3) biological improvement: planting salt-tolerant pioneer plants such as Tamarix and Elaeagnus angustifolia to absorb salt or improve soil structure; 4) mulching to inhibit salt: covering the ground to reduce evaporation and return of salt; 5) contaminated soil remediation: adopting physical (soil import, leaching), chemical (passivation agents), biological (hyperaccumulators) and other methods depending on the type and extent of contamination.