A method for transforming a low-efficiency forest into a forest-water complex forest

Abstract

The application discloses a forest-water combined low-efficiency forest reconstruction method, which is based on a forest-water combined reconstruction method of "vertical gradient design-vegetation layering configuration-hydrological dynamic regulation", and a low-efficiency forest reconstruction system of "mutual aid between forest and water, habitat diversity and function combination" is constructed based on a natural succession rule, so that the problems of water regulation imbalance and single ecological structure in traditional reconstruction are effectively solved, the forest land regulation and storage capacity, biodiversity and carbon sink and water purification function are improved, and the transformation of the low-efficiency forest into an efficient composite ecological system is realized.

Description

Technical Field

[0001] This invention relates to the field of forestry technology, and in particular to a method for transforming inefficient forests with combined forestry and water resources. Background Technology

[0002] Low-efficiency forests refer to forest stands with low productivity and weak ecological functions due to factors such as unreasonable tree species configuration, unbalanced water regulation, and a simple ecological structure. The key issues currently facing the transformation of low-efficiency forests are as follows:

[0003] The forest-water system is fragmented: Traditional transformation focuses only on the trees themselves, ignoring the synergistic effect between forest land and water system, resulting in waterlogging during the flood season (increasing the incidence of waterlogging by 30%-40%) and insufficient water during the dry season (soil moisture content is 20%-30% lower than the suitable value), which restricts the growth of trees.

[0004] Imbalanced ecological structure: high proportion of single tree species (often exceeding 70%), lack of vegetation in the water-land transition zone, fragmentation of biological habitats (amphibian and bird populations reduced by 40%-50%), and 25%-35% higher incidence of diseases and pests than healthy forest stands.

[0005] Low functional efficiency: weak water storage capacity (the flood storage efficiency of traditional forest land is only 30%-40%), insufficient water purification (TN removal rate <20%), and carbon sequestration capacity is 20%-25% lower than that of complex ecosystems. Summary of the Invention

[0006] In view of this, the present invention provides a method for transforming inefficient forests into integrated forest-water systems, applicable to the systematic ecological restoration and productivity enhancement of various types of inefficient forest lands adjacent to water. This method is based on a forest-water synergistic transformation approach of "vertical gradient design - vegetation stratification configuration - hydrological dynamic regulation". Based on the laws of natural succession, it constructs an inefficient forest transformation system of "mutual support between forest and water, habitat diversity, and functional integration", effectively solving problems such as water regulation imbalance and single ecological structure in traditional transformation, enhancing the forest land's water storage capacity, biodiversity, and carbon sequestration and water purification functions, and realizing the transformation of inefficient forests into efficient integrated ecosystems.

[0007] A method for transforming inefficient forests in a combined forest-water system includes the following steps:

[0008] S1, Diagnose the current status of the aforementioned low-efficiency forest-water composite forest;

[0009] S2. Based on the current status of the low-efficiency forest in the forest-water complex, the adjacent water beach is transformed into a vertical gradient terrain composed of low beach terraces, medium beach terraces and high beach terraces with different topographic slopes. The low beach terraces retain their original natural slopes and their original hard revetments are removed and replaced with wooden pile ecological revetments. The spaces between the wooden piles are filled with a mixture of humus and gravel.

[0010] S3, excavate an underground infiltration channel at a set depth in the vertical gradient terrain, and construct a gravity overflow system on the ground surface of the vertical gradient terrain;

[0011] A three-dimensional drainage network is constructed on the high beach terraces of the vertical gradient terrain;

[0012] S4, Reconstruct a multi-layered three-dimensional vegetation system on the vertical gradient terrain;

[0013] S5, construct habitat creation facilities on the vertical gradient terrain;

[0014] S6 simulates high and low water levels to adjust the three-dimensional drainage network and gravity overflow system, ensuring stable drainage and water replenishment regulation functions;

[0015] S7 involves regular maintenance of the gravity overflow system, three-dimensional drainage network, multi-layered three-dimensional vegetation system, and habitat creation facilities.

[0016] Preferably, the specific steps for constructing a gravity overflow system on the ground of the multi-level vertical gradient terrain in step S3 are as follows:

[0017] Multi-tiered terraced water retention ponds were excavated along contour lines on the high beach terraces, with adjacent water retention ponds on the upper and lower tiers separated by earthen embankments;

[0018] A stepped ecological weir was arranged on the Zhongtan terrace. A shallow pond-ridge composite terrain was constructed between the upper and lower ecological weirs, and water level sensors were buried at the edge of the shallow pond.

[0019] Multiple overflow ditches were excavated on the surface of the low-lying terraces, and a second gravel layer was laid in the ditches. Overflow weirs were set up on the water-adjacent banks of the low-lying terraces, and ecological gaps were reserved on the banks.

[0020] Preferably, the shallow pond-ridge composite terrain includes multiple shallow ponds and ridges set between two adjacent shallow ponds.

[0021] Preferably, when constructing the shallow pond-ridge composite terrain, if the current status diagnosis results of the forest-water composite low-efficiency forest show that its water quality index is greater than the set value, then the total area of ​​the shallow pond is designed to be 40%-50% of the total area of ​​the central terrace, and an artificial aeration device is added to the shallow pond; if the current status diagnosis results of the forest-water composite low-efficiency forest show that its water quality index is less than the set value, then the total area of ​​the shallow pond is designed to be 20%-30% of the total area of ​​the central terrace.

[0022] Preferably, when the water level in the shallow pond is lower than the normal water level, water can be replenished to the shallow pond using underground infiltration channels.

[0023] Preferably, the specific steps in step S3 for constructing a three-dimensional drainage network on the high beach terrace of the vertical gradient terrain are as follows:

[0024] Multiple shallow, strip-shaped ditches with the first slope were excavated on the surface of the high-slope plateau, and the first gravel layer was laid in the ditches.

[0025] Tree planting trenches are dug on both sides of the strip shallow trench. Permeable branch pipes connected to the underground infiltration channel are buried at the bottom of the tree planting trench and the strip shallow trench. During drought, the underground infiltration channel can be used to replenish water to the terrace soil through the permeable branch pipes.

[0026] Drainage ditches were excavated on the surface of the high-slope terraces, connecting to the strip-shaped shallow ditch.

[0027] Preferably, the specific steps for reconstructing the multi-layered three-dimensional vegetation system on the vertical gradient terrain in step S4 are as follows:

[0028] Planting a multi-layered terrestrial plant system combined with a ground cover layer on the high beach terraces creates a vertical vegetation structure, forming a high beach sparse forest terrace.

[0029] A multi-layered aquatic plant system combined with a moisture-tolerant shrub layer was planted in the shallow pond-ridge complex terrain of the Zhongtan terrace to form a vertical vegetation structure, thus creating the Zhongtan ecological wetland.

[0030] Emergent plants are planted along the direction of water flow on the low-lying terraces.

[0031] Preferably, the multi-layered terrestrial plant system planted on the high beach terrace includes a tree layer, a shrub layer and a herb layer. The tree layer is planted along both sides of the strip-shaped shallow ditch, the shrub layer is located under the shade of the tree layer, the herb layer is located below the shrub layer, and the shrub layer is also planted on the earthen embankment between the upper and lower adjacent stagnant ponds.

[0032] Preferably, the multi-layered aquatic plant system for planting in the shallow pond-ridge composite terrain of the central terrace includes a submerged plant layer, a floating-leaved plant layer, an emergent plant layer, and a shrub layer. The submerged plant layer is planted at the bottom of the shallow pond, and floating islands are set in the shallow pond. Floating-leaved plants are planted on the floating islands. Emergent plants are planted on the ridges and at the edges of the shallow pond. The shrub layer is planted on the ridges, and the surface of the ridges is covered with permeable geotextile.

[0033] Preferably, the specific steps for constructing habitat creation facilities on the vertical gradient terrain in step S5 are as follows:

[0034] Set up fallen logs covered with epiphytic moss in the transition zone of the high beach terrace, and build wooden boardwalks between the strip-shaped shallow ditches.

[0035] Artificial reefs were set up in the shallow ponds of the Zhongtan Terrace, and wooden boardwalks were built between the shallow ponds.

[0036] At the ecological gaps in the embankments of the low-lying terraces, piles of fallen logs covered with epiphytic moss and artificial reefs are set up, and wooden boardwalks are built between the overflow channels.

[0037] The beneficial effects of this invention are:

[0038] 1. The three-tiered terraced forest-water complex ecosystem transformed by this invention achieves natural water regulation and infiltration through the elevation differences between high, medium, and low terraces, breaking through the limitations of traditional single-planar transformation of low-efficiency forests, reducing the risk of forest waterlogging, and constructing a multi-layered vegetation system from emergent plants to terrestrial trees on the high, medium, and low terraces, forming a complete ecological chain, enhancing biodiversity and ecological functions, and constructing a "structurally stable, functionally complex, and self-sustaining" forest-water complex system, providing a replicable technical paradigm for the transformation of low-efficiency forests in different regions of the country.

[0039] 2. This invention utilizes a three-element regulation mechanism of "elevation difference drive-vegetation damping-soil infiltration" to form a gravity overflow system through a 0.5-1.0m elevation difference of the terrace, which reduces energy consumption by 100% compared to traditional electric gate regulation. Combined with gravel layer infiltration and plant root blockage, it achieves hydrological and ecological regulation without electricity dependence. Attached Figure Description

[0040] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of the three-tiered terraced forest-water composite ecosystem modified according to the present invention.

[0042] The labels in the diagram mean:

[0043] 1 is a low-lying terrace, 2 is a medium-lying terrace, 3 is a high-lying terrace, 4 is an underground infiltration channel, 5 is a stagnant pond, 6 is an ecological weir, 7 is a flood ditch, 8 is a second gravel layer, 9 is an overflow weir, 10 is a shallow pond, 11 is a drainage ditch, 12 is a first gravel layer, 13 is a branch pipe of the permeable channel, 14 is an artificial reef, and 15 is a pile of fallen logs. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0045] The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. The singular forms “a,” “the,” and “the” as used in this disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0046] It should be understood that although the terms first, second, etc., may be used in this disclosure to describe various information, such information should not be limited to these terms and should not be construed as indicating or implying relative importance. These terms are used only to distinguish information of the same type from one another. For example, without departing from the scope of this disclosure, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0047] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0048] In the description of this invention, unless otherwise specified and limited, it should be noted that the terms "installation", "connection" and "linking" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two components. They can be direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0049] To better understand the technical solution of the present invention, the present invention will be described in detail below with reference to the accompanying drawings.

[0050] This invention provides a method for transforming inefficient forests in a combined forest-water system, specifically including the following steps:

[0051] S1, diagnose the current status of the low-efficiency forest-water composite forest, including the normal water level, topography, soil moisture content, groundwater level, vegetation composition, and water quality of the low-efficiency forest-water composite forest.

[0052] When detecting the normal water level of the forest-water composite low-efficiency forest, a level with an accuracy error of ±1cm is used to measure the average water level line over many years (based on long-term observation data from the local hydrological station). Concrete reference piles (10cm in diameter and 1.5m deep) are buried on the bank of the water body, and a normal water level mark line is engraved on the top of the concrete reference pile as a reference for terrace construction and water level monitoring.

[0053] When conducting topographic surveys of the aforementioned low-efficiency forest-water composite forest, the accuracy error of the topographic mapping should be within ±5cm.

[0054] When testing the soil moisture content of the aforementioned low-efficiency forest-water composite forest, the soil moisture content of the target area should not be less than 25%.

[0055] When measuring the groundwater level of the aforementioned low-efficiency forest-water composite forest, the accuracy error of the normal water level measurement should be within ±1.0m.

[0056] If the proportion of water-tolerant species in the vegetation composition of the aforementioned low-efficiency forest-water composite forest is less than 30%, water-tolerant species need to be replanted.

[0057] If the water quality indicators of the aforementioned low-efficiency forest-water composite forest are TN > 5 mg / L and TP > 0.3 mg / L, then the total area of ​​the shallow pond should be designed to be 40%-50% of the total area of ​​the central terrace. Artificial aeration devices should be added to the shallow pond, and submerged plants (such as Vallisneria natans and Hydrilla verticillata) and floating-leaved plants (water lilies) should be densely planted to form a composite purification system of "vegetation filtration - microbial degradation - water reoxygenation". If the current status diagnosis results of the aforementioned low-efficiency forest-water composite forest show that its water quality indicators are less than the set values, then the total area of ​​the shallow pond should be designed to be 20%-30% of the total area of ​​the central terrace.

[0058] The water quality testing indicators for the forest-water composite low-efficiency forest typically include three indicators: COD, TN, and TP.

[0059] S2. Based on the current status of the low-efficiency forest in the forest-water composite area, the adjacent water beach is transformed into a vertical gradient terrain consisting of low beach terrace 1, medium beach terrace 2 and high beach terrace 3 with different topographic slopes. Among them, low beach terrace 1 is adjacent to the water body. Low beach terrace 1 retains its original natural slope and removes its original hard revetment, replacing it with a wooden pile ecological revetment. The spaces between the wooden piles are filled with a mixture of humus and gravel.

[0060] Specifically, in this embodiment, the ecological revetment is made of pine wood piles. The pine wood piles are 2.5m long, and the distance between two adjacent pine wood piles is 1.2m. The ratio of humus to gravel filling the space between the wood piles is humus:gravel = 3:1.

[0061] S3, excavate underground infiltration channels 4 at a set depth in the vertical gradient terrain, construct a gravity overflow system on the ground surface of the vertical gradient terrain, and construct a three-dimensional drainage network on the high beach terrace 3 of the vertical gradient terrain.

[0062] Specifically, firstly, underground permeation channels are excavated at a set depth throughout the vertical gradient terrain;

[0063] Then, on the high beach terrace 3, multi-level terraced water retention ponds 5 are excavated along the contour lines. The upper and lower adjacent water retention ponds 5 are separated by earthen ridges. On the terrace upstream of the water retention ponds 5, multiple strip-shaped shallow ditches with the first slope are excavated and the first gravel layer 12 is laid in the ditches to enhance the rainwater infiltration capacity. Drainage ditches 11 connected to the strip-shaped shallow ditches are also excavated. The location and number of strip-shaped shallow ditches and drainage ditches 11 are determined according to actual needs. Tree planting ditches are excavated on the ground on both sides of the strip-shaped shallow ditches. Permeable branch pipes 13 connected to the underground infiltration channel 4 are buried at the bottom of the tree planting ditches and strip-shaped shallow ditches.

[0064] A stepped distribution of ecological weirs 6 is arranged on the central terrace 2. The ecological weirs 6 are used to slow down the water flow to form a water flow slowdown zone. A shallow pond-ridge composite terrain is constructed between the upper and lower ecological weirs 6. The shallow pond-ridge composite terrain includes multiple shallow ponds 10 and ridges set between two adjacent shallow ponds 10. The surface of the ridges is covered with permeable geotextile to enhance the erosion resistance. Water level sensors are buried at the edge of the shallow ponds 10 to monitor the water level changes in the shallow ponds 10 in real time.

[0065] Multiple overflow ditches 7 are excavated on the ground of the low-lying terrace 1 and a second gravel layer 8 is laid in the ditches. An overflow weir 9 is set up on the water-adjacent bank of the low-lying terrace 1 and an ecological gap (2-3m wide, 1:5 slope) is reserved on the bank. The low-lying terrace 1 retains its original natural mudflat slope and is not hardened. The original mudflat topography is used to buffer the impact of floods and form a seasonal overflow channel.

[0066] S4, Reconstruct a multi-layered three-dimensional vegetation system on the vertical gradient terrain.

[0067] Specifically, a multi-layered terrestrial plant system combined with a ground cover layer is planted on the high beach terrace 3 to form a high beach sparse forest terrace. The multi-layered terrestrial plant system includes a tree layer, a shrub layer and a herb layer. Trees are planted in the planting trenches dug on both sides of the strip shallow ditch and on the earthen ridges between the upper and lower adjacent water retention ponds 5. Shrubs are planted under the shade of the trees and herbs are planted under the shrub layer.

[0068] A multi-layered aquatic plant system combined with a moisture-tolerant shrub layer is planted in the shallow pond-ridge composite terrain of Zhongtan Terrace 2 to form a Zhongtan ecological wetland. The multi-layered aquatic plant system planted in the shallow pond-ridge composite terrain includes a submerged plant layer, a floating-leaved plant layer, an emergent plant layer, and a shrub layer. The submerged plant layer is planted at the bottom of the shallow pond 10, and the cutting depth of the submerged plant layer is 10-15cm. Artificial floating islands are set in the shallow pond 10, and floating-leaved plants are planted on the artificial floating islands (planting spacing is 1.5m). Emergent plants are divided and transplanted on the ridges and the edge of the shallow pond 10 (planting spacing is 1.0m). The shrub layer is planted on the ridges, and the surface of the ridges is covered with permeable geotextile to enhance the erosion resistance.

[0069] Emergent plants were planted along the direction of water flow on the low-lying terrace 1.

[0070] S5, construct habitat creation facilities on the vertical gradient terrain.

[0071] Specifically, fallen logs covered with epiphytic moss were set up in the transition zone of the embankment of the high beach terrace 3, and wooden walkways were built between its strip-shaped shallow ditches.

[0072] Artificial reefs 14 are set up in the shallow ponds of Zhongtan Terrace 2, and wooden boardwalks are built between the shallow ponds.

[0073] Humus and wood chips were laid at the ecological gap in the embankment of the low-lying terrace 1 to form an amphibian migration route, improving connectivity efficiency by 70%; and fallen logs 15 with epiphytic moss and artificial reefs were set up at the ecological gap in the embankment, and wooden boardwalks were built between the overflow channels 7.

[0074] The surface of the fallen log pile 15 is covered with moss (moss coverage ≥70%), which can provide habitat for insects and birds, increasing species richness by 30%, and the fallen log pile can also intercept floating objects in the water flow. The fallen logs used in the fallen log pile are ≥20cm in diameter and 2-3m in length, and the stacking distance of the fallen log pile 15 is 50m.

[0075] The artificial reef 14 consists of a concrete frame and pebbles filled in the concrete frame. The spacing between the artificial reefs arranged at the above locations is at least 20m. The artificial reef 14 can create a eddy zone (flow velocity 0.1-0.3m / s), attracting benthic organisms to gather, and the density of benthic organisms can be increased by 40%. The artificial reef can also deposit silt in the water flow.

[0076] The wooden boardwalk is 1.5m higher than the normal water level at its location, and a 50cm diameter observation hole is provided at the bottom of the boardwalk to provide passage space for fish and small mammals.

[0077] S6 simulates high and low water levels to adjust the three-dimensional drainage network and gravity overflow system, ensuring stable drainage and water replenishment regulation functions.

[0078] S7 involves regular maintenance of the gravity overflow system, three-dimensional drainage network, multi-layered three-dimensional vegetation system, and habitat creation facilities.

[0079] Specifically, regular maintenance items include:

[0080] (1) Quarterly cleanup: Remove floating objects from stagnant ponds, drainage ditches, strip shallow ditches, shallow ponds, overflow ditches, etc., and harvest reeds (leaving a stubble of 10cm) to prevent biological blockage;

[0081] (2) Replanting vegetation: Replant water-tolerant trees the following spring when the survival rate is <80%; replant aquatic plants in summer when the coverage is <50%.

[0082] (3) Data monitoring: Record water level, water quality and vegetation growth data monthly and establish archives (retention period ≥ 5 years).

[0083] The drainage ditch 11 excavated on the high beach terrace 3 can quickly divert surface runoff or water accumulation, and divert the water flow to the strip shallow ditch. The gravel layer 12 and plant roots laid in the strip shallow ditch can accelerate the infiltration rate of the water flow, which can increase the infiltration rate to 60%. The groundwater that infiltrates into the ground is introduced into the underground infiltration ditch 4 through the permeable ditch branch pipe 13.

[0084] In the event of heavy rain, if drainage ditch 11 and the strip-shaped shallow ditch cannot effectively drain surface rainwater, the surface rainwater can flow down the sloping terrain of the high riverbank terrace into the retention pond 5, each of which can retain 500m³ of water. 3 Water volume; if the rainfall is too heavy and the water in the retention pond 5 is full, the water will flow down the terrain to the shallow pond 10 in the middle terrace. If the water level in the shallow pond 10 exceeds the top of the ecological weir 6, the water will automatically overflow downwards step by step until it is discharged to the low terrace 1. The overflow ditch 7 of the low terrace 1 will continue to receive the flood. The overflow ditch 7 can discharge floodwater into the water body, thus forming natural regulation or flood discharge through the terrain difference of the entire vertical gradient, eliminating the need for electric gates, and the regulation efficiency reaches 40%-50%.

[0085] During flood discharge or flood season (water level > normal water level + 0.5m), the gravel layer in the strip shallow ditch and overflow ditch 7 can perform secondary filtration of the water flow, filtering out more than 90% of SS. In addition, the fallen log piles 15 set at the embankment transition zone of the high beach terrace 3 and the ecological gap of the embankment of the low beach terrace 1 can intercept floating objects in the water flow. The artificial reefs 14 set at the shallow pond in the middle beach terrace 2 and the ecological gap of the embankment of the low beach terrace 1 can deposit silt to purify the water quality.

[0086] During the dry season, the overflow ditch 7 of the low-lying terrace 1 can serve as a migration route for amphibians, and the fallen log area can maintain a water depth of 0.5m to provide habitat for aquatic organisms.

[0087] During the dry season, the underground infiltration canal 4 can extract water from wetland ponds and replenish the soil of the terraces through the infiltration canal branch pipe 13; if necessary, it can also extract water from the river to replenish the various terraces.

[0088] The specific embodiments of the present invention will be described in detail below through specific examples.

[0089] First, the current status of the low-efficiency forest-water composite forest is diagnosed, including normal water level, topography, soil moisture content, groundwater level, vegetation composition, and water quality.

[0090] Then, earthwork excavation is carried out: terrain modification is carried out according to the three-level terrace design, and ponds are excavated, etc.

[0091] Specifically, adjacent to the edge of the water body, 0.5-1.0m down from the normal water level, the original 1:15-1:20 natural mudflat slope of the area is preserved without hardening. The original mudflat topography is used to buffer the impact of floods. An overflow weir 9 with a height of 0.3m is set at the adjacent embankment, and an ecological gap is reserved on the embankment with a width of 2-3m and a slope of 1:5. An 8m wide overflow ditch 7 is excavated upstream of the overflow weir 9 along the mudflat slope of 1:15-1:20, and a 50cm thick gravel layer 8 is laid in the ditch to form a low-lying terrace 1.

[0092] On the inner side of the low-lying terrace 1, a three-level "shallow pond-ridge" composite micro-topography is constructed ±0.5m above the normal water level. The area of ​​the shallow pond 10 accounts for 20%-30% of the total area of ​​the low-lying area, and the water depth of the shallow pond 10 is 0.3-1m (preferably 0.5-0.8m). The shallow pond 10 and the ridge are arranged alternately. Between the upper and lower "shallow pond-ridge" composite micro-topography, a trapezoidal ecological weir 6 with a height of 0.5m is set up using C15 plain concrete (the weir width is 50-100mm, and the slope of the weir crest facing the water is 1:1.5). Water level sensors with an accuracy of ±1cm are buried at the edge of the shallow pond 10 to monitor the water level changes of the shallow pond 10 in real time, forming the middle terrace 2.

[0093] On the inner side of Zhongtan Terrace 2, excavate a slope of 1:8-1:10 parallel to the contour lines, 0.5-1.0m upwards from the normal water level. Construct a drainage ditch 11 with a bottom width of 4m (slope 0.5%) on the top surface of this terrace. Upstream of this slope, excavate a 30cm deep strip of shallow trench at 5-8m intervals (6m spacing between the strips). Lay a 20-40mm thick gravel layer 12 (preferably 30cm thick) inside the trench. Tree planting trenches are dug on both sides of the shallow ditch, and DN300 permeable branch pipes 13 (with a permeable pipe spacing of 20m) are buried. Permeable branch pipes 13 are connected to underground infiltration channels 4 with a bottom diameter of 500mm. Underground infiltration channels 4 are connected to the three-level terrace drainage system. Three-level retaining ponds 5 (10m long × 5m wide × 0.8m deep) are dug along the contour lines on this slope. The ponds are separated by earthen embankments (1m wide at the top). Willows are planted on the embankments (1.5m apart) to form a high beach terrace.

[0094] Then, vegetation restoration is carried out:

[0095] Specifically, the vegetation stratification configuration of the low-lying terraces is shown in the table below:

[0096]

[0097] Low-lying beach vegetation type: single-layer emergent vegetation zone; vertical structure: height 1.5-3.0m (above water surface);

[0098] The vegetation stratification of the Zhongtan terrace is shown in the table below:

[0099]

[0100]

[0101] Vegetation type in the central beach: a three-layered aquatic plant system + a moisture-tolerant shrub layer; Vertical structure: 0.8m underwater to 2.0m above the water surface.

[0102] The vegetation stratification of the high-slope terraces is shown in the table below:

[0103]

[0104] High beach vegetation type: three-layer terrestrial plant system + ground cover layer. Vertical structure: height from ground to canopy layer is 8-15m.

[0105] The three-tiered terraced forest-water complex ecosystem transformed using the method of this invention is shown in the table below:

[0106]

[0107]

[0108] Then, a water level regulation test was conducted: the drainage and water replenishment systems were tested under high and low water levels to ensure the stability of the regulation function.

[0109] After the renovation is completed, long-term regular operation and maintenance will be carried out.

[0110] The three-tiered terraced forest-water complex ecosystem transformed using the method of this invention can simultaneously improve its water storage capacity, water purification capacity, and biodiversity in multiple dimensions. The water storage capacity of the forest-water complex area is increased compared to traditional forest land, the waterlogging time during a 5-year rainstorm is shortened, and the risk of waterlogging is reduced. Through vegetation filtration and microbial decomposition, the removal rates of TN and TP are greatly improved, and the water quality level is improved to meet the GB3838 Class IV standard. In addition, the populations of amphibians and birds increase, forming a four-layered three-dimensional habitat of "trees-shrubs-herbs-aquatic plants", thus improving species richness.

[0111] The three-tiered terraced forest-water complex ecosystem transformed using the method of this invention is expected to see an average annual increase of 1.5-2.0 cm in diameter at breast height (DBH) for target tree species over three years, a 50% increase compared to before the transformation; an annual increase of 10%-15% in timber volume; and an estimated increase of 25%-30% in carbon storage compared to single-species, low-efficiency forests, with an annual increase of 0.8-1.2 tons of carbon sequestration per acre, facilitating the development of forestry carbon sequestration projects. Furthermore, it will create a four-season landscape of "flowers in spring, cool shade in summer, foliage in autumn, and birdwatching in winter," boosting ecotourism; the establishment of monitoring stations and guided trails will host 50-100 science popularization activities annually; and it will reduce the threat of floods to surrounding farmland and villages, lowering the risk of inundation by 40% and enhancing the region's ecological resilience.

[0112] It should be understood that the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A method for transforming inefficient forests through forest-water integration, characterized in that, Specifically, the following steps are included: S1, Diagnose the current status of the aforementioned low-efficiency forest-water composite forest; S2, based on the current status of the low-efficiency forest in the forest-water composite, the adjacent water beach is transformed into a vertical gradient terrain consisting of low beach terraces (1), medium beach terraces (2) and high beach terraces (3) with different topographic slopes. The low beach terraces (1) retain their original natural slopes and remove their original hard revetments, replacing them with wooden pile ecological revetments. The spaces between the wooden piles are filled with a mixture of humus and gravel. S3, excavate an underground infiltration channel (4) at a set depth in the vertical gradient terrain, and construct a gravity overflow system on the ground of the vertical gradient terrain; A three-dimensional drainage network is constructed on the high beach terraces of the vertical gradient terrain; The specific steps for constructing a gravity overflow system on the ground of the vertical gradient terrain are as follows: On the high beach terrace (3), multi-level terraced water retention ponds (5) are excavated along the contour lines, and the upper and lower adjacent water retention ponds (5) are separated by earthen embankments; In the Zhongtan Terrace (2), a stepped distribution of ecological weirs (6) is arranged. A shallow pond-ridge composite terrain is constructed between the upper and lower ecological weirs, and water level sensors are buried at the edge of the shallow pond. Multiple overflow ditches (7) were dug on the ground of the low beach terrace (1) and a second gravel layer (8) was laid in the ditches. An overflow weir (9) was set up on the water-adjacent bank of the low beach terrace (1) and an ecological gap was reserved on the bank. The specific steps for constructing a three-dimensional drainage network on the high beach terraces of the vertical gradient terrain are as follows: Multiple shallow strips with a first slope were excavated on the surface of the high beach terrace (3), and a first gravel layer (12) was laid in the trenches. Tree planting trenches are dug on the ground on both sides of the strip shallow trench. Permeable branch pipes (13) connected to the underground infiltration channel (4) are buried at the bottom of the tree planting trench and the strip shallow trench. During drought, the underground infiltration channel (4) can be used to replenish water to the terrace soil in the reverse direction through the permeable branch pipes (13). Drainage ditches connected to the strip-shaped shallow ditch were excavated on the surface of the high beach terrace (11). S4, Reconstruct a multi-layered three-dimensional vegetation system on the vertical gradient terrain; S5, construct habitat creation facilities on the vertical gradient terrain; S6 simulates high and low water levels to adjust the three-dimensional drainage network and gravity overflow system, ensuring stable drainage and water replenishment regulation functions; S7 involves regular maintenance of the gravity overflow system, three-dimensional drainage network, multi-layered three-dimensional vegetation system, and habitat creation facilities.

2. The method for transforming inefficient forests into forest-water integrated forests according to claim 1, characterized in that, The shallow pond-ridge composite terrain includes multiple shallow ponds (10) and ridges set between two adjacent shallow ponds (10).

3. The method for transforming inefficient forests into forest-water integrated forests according to claim 1, characterized in that, When constructing the shallow pond-ridge composite terrain, if the current status diagnosis results of the forest-water composite low-efficiency forest show that its water quality index is greater than the set value, the total area of ​​the shallow pond (10) is designed to be 40%-50% of the total area of ​​the central terrace, and an artificial aeration device is added in the shallow pond (10); if the current status diagnosis results of the forest-water composite low-efficiency forest show that its water quality index is less than the set value, the total area of ​​the shallow pond (10) is designed to be 20%-30% of the total area of ​​the central terrace.

4. The method for transforming inefficient forests into forest-water integrated forests according to claim 1, characterized in that, When the water level in the shallow pond is lower than the normal water level, the underground infiltration channel (4) can be used to replenish the water in the shallow pond.

5. The method for transforming inefficient forests into forest-water integrated forests according to claim 1, characterized in that, The specific steps for reconstructing the multi-layered three-dimensional vegetation system on the vertical gradient terrain in step S4 are as follows: Plant a multi-layered terrestrial plant system combined with a ground cover layer on the high beach terrace (3) to form a high beach sparse forest terrace; In the shallow pond-ridge complex terrain of the Zhongtan Terrace (2), a multi-layered aquatic plant system combined with a moisture-tolerant shrub layer is planted to form a vertical vegetation structure, thus creating the Zhongtan ecological wetland. Emergent plants are planted along the direction of water flow on the low-lying terrace (1).

6. The method for transforming inefficient forests into forest-water integrated forests according to claim 5, characterized in that, The multi-layered terrestrial plant system planted on the high beach terrace includes a tree layer, a shrub layer and a herb layer. The tree layer is planted along both sides of the strip-shaped shallow ditch, the shrub layer is located under the shade of the tree layer, the herb layer is located below the shrub layer, and the shrub layer is also planted on the earthen embankment between the upper and lower adjacent stagnant ponds (5).

7. The method for transforming inefficient forests into forest-water integrated forests according to claim 5, characterized in that, The multi-layered aquatic plant system for planting in the shallow pond-ridge composite terrain of the Zhongtan Terrace includes a submerged plant layer, a floating-leaved plant layer, an emergent plant layer and a shrub layer. The submerged plant layer is planted at the bottom of the shallow pond (10), and floating islands are set up in the shallow pond. Floating-leaved plants are planted on the floating islands, emergent plants are planted on the ridges and the edge of the shallow pond, and the shrub layer is planted on the ridges. The surface of the ridges is covered with permeable geotextile.

8. The method for transforming inefficient forests into forest-water integrated forests according to claim 1, characterized in that, The specific steps for constructing habitat creation facilities on the vertical gradient terrain in step S5 are as follows: Set up fallen logs covered with epiphytic moss in the transition zone of the high beach terrace, and build wooden boardwalks between the strip-shaped shallow ditches. Artificial reefs (14) were set up in the shallow ponds (10) of the Zhongtan Terrace, and wooden boardwalks were built between the shallow ponds; Set up fallen logs (15) with epiphytic moss and artificial reefs at the ecological gaps in the embankment of the low-lying terraces, and build wooden walkways between the overflow channels (7).

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