CN102804991A - Rapid method for promoting ecological restoration of damaged ecological system under extreme arid environment - Google Patents

Abstract

The invention relates to a rapid method for promoting the ecological recovery of damaged ecosystems in an extreme drought environment. The method utilizes natural vegetation composition, community dynamics, reproduction methods and the natural succession process of desert vegetation communities, and combines artificial ecological recovery with natural recovery. The combined method accelerates the recovery of desert plants. At the same time, the law of water and salt migration in desert areas and the stimulation of flood irrigation methods on the seed bank are used to improve the breeding habitat of lost species in degraded communities, thereby achieving the goal of promoting damaged ecosystems in extreme drought environments. The purpose of ecological restoration is to improve the efficiency of ecological restoration in arid desert areas where the precipitation is less than 100mm, the evaporation is greater than 2000mm, and the surface water is seriously lacking. Through plant provenance compensation and habitat improvement, the diversity of desert plant communities is increased, and the community structure is increased. stability, improving the self-sustainability of the restored plant community.

Description

Rapid method to promote ecological restoration of damaged ecosystems in extreme drought environments

technical field

The invention relates to a method for improving the breeding environment in arid desert areas and accelerating ecological restoration, in particular to a method for artificial provenance supplementation and habitat improvement.

Background technique

Species diversity is the result of the long-term evolution of life on earth, and it is the material basis for human survival. Species diversity is a necessary condition for maintaining the relative balance of the ecosystem. Preventing soil erosion, regulating climate, absorbing and decomposing pollutants, storing nutrients, promoting nutrient cycling and maintaining evolution are all indirectly related to species diversity. The diversity of species means that the ecological system has a complex structure, a high degree of network, and strong heterogeneity. There are many and dense channels for energy, material and information input and output, criss-crossing and unimpeded, so the flow is large, the flow rate is fast, and the productivity is high. . Even if individual pathways are destroyed, the system will ensure the normal operation of energy flow, material flow, and information flow due to mutual generation and restraint, mutual compensation and substitution among various species, so that the damaged part of the system structure can be quickly repaired and the original system can be restored. stable state, or form a new stable state, therefore, the extinction of some species may cause the entire system to become unbalanced or even collapse. Due to the rapid growth of the world's population and the continuous intensification of human economic activities, species diversity is facing increasingly serious threats. Due to large-scale human activities and water and soil resources development activities in the arid desert area, the ecosystem is seriously damaged, which in turn leads to the degradation of ecosystem services and the reduction of species diversity. The environmental problem of the Tarim River Basin is stand out. In the past 50 years, due to the intensive development of human beings with the development and utilization of water resources as the core, the downstream 320km river course has been cut off, and the ecosystem dominated by natural vegetation has been seriously affected. Lakes have dried up, groundwater levels have dropped, and perennial herbaceous vegetation has degraded and died. The surviving Tamarix shrubs are in decline, the woodland is sparse, and the desertification is intense. Affected by the drought, the plant ecosystem in the lower reaches of the Tarim River experienced herbaceous degradation, shrub degradation, and arbor degradation, forming a community dominated by Populus euphratica, Tamarix or either of them. The vegetation structure tends to be simple and homogeneous, and the species diversity is serious. missing.

The ecological water transportation in the lower reaches of the Tarim River adopts the "linear" water transportation method along the natural channel, which is a life-saving process. Although it played an important role in raising the groundwater level near the river channel and saving the declining natural vegetation at the beginning, it was difficult to achieve the goal of Populus euphratica. The regeneration of plants such as willow, tamarisk, etc., the vegetation recovery process is slow, and the recovery is a line, not a surface, and the recovery range is extremely limited. Although some large trees and shrubs have been rescued and rejuvenated, the herbaceous plants have not improved significantly, and the community structure is still monotonous, especially in the downstream, and the activation of sandy land in the forest has not been curbed. In the vertical direction, from upstream to downstream, with the increase of water transportation distance, the impact of ecological water transportation on groundwater level is weakened, and the vegetation restoration is also poor; in the horizontal direction, the response range of groundwater level to water transportation is within 850m, And the intensity of the impact slows down as the distance away from the water delivery channel, beyond 850mm, the water delivery process has basically no impact on the groundwater level. Therefore, in order to accelerate the restoration of natural vegetation, according to the physiological characteristics and hydrological conditions of the plants in the Tarim River, in the area close to the water source, the soil seed bank and seed flow are used to carry out community transformation; The amount of incoming water is large, and the overflow of the river and the surface of the water are used to activate the soil seed bank, thereby increasing the surface coverage and accelerating the recovery of natural vegetation.

Taking into account the natural physiological conditions of plants in the lower reaches of the Tarim River, and taking into account the economic and technical feasibility of new technology methods, using the principle of locality of biological species, the seeds of Populus euphratica, Tamarix, licorice, bell thorn and Nitraria were collected from July to October Used for provenance replenishment, it helps to alleviate the reverse succession of desert vegetation in the lower reaches of the Tarim River; using the law of water and salt migration in desert areas, ditches are pre-drilled to store water in areas where ecological restoration is carried out, and soil salt is transported to the soil through water Saturated layer until it spreads to the deep layer of the soil, and then achieves the effect of gradually pressing down the salt; using the seasonal variation of the runoff of the Tarim River, use the abandoned water to replenish the desert vegetation from August to September, and use the reclaimed water before irrigation The furrows are guided according to the situation, and the abandoned water is irrigated as evenly as possible; the seeds of Populus euphratica, Tamarix, licorice, bell thorn and Nitraria are sowed at the inlet of flood irrigation by using the natural dispersal mode and natural reproduction law of vegetation seeds to simulate the natural growth of plant populations Process: Utilizing the water utilization characteristics of plant species colonization, replenish water twice in the second year to guide the root system to extend to the deep layer, so as to achieve the self-sustaining effect of plant growth.

Contents of the invention

The purpose of the present invention is to provide a rapid method for promoting ecological recovery of damaged ecosystems under extreme drought conditions. The method utilizes natural vegetation composition, community dynamics, reproductive methods and the natural succession process of desert vegetation communities, through artificial ecological restoration and The method of combining natural restoration has accelerated the restoration of desert plants. At the same time, the law of water and salt migration in desert areas and the stimulation of flood irrigation methods on the seed bank have been used to improve the breeding habitat of lost species in degraded communities, so as to promote the recovery of plants affected by extreme drought. The purpose of ecological restoration of damaged ecosystems is to improve the efficiency of ecological restoration in arid desert areas where precipitation is less than 100mm, evaporation is greater than 2000mm, and surface water is seriously lacking, and to promote the diversity of desert plant species.

The rapid method for promoting the ecological recovery of the damaged ecosystem under the extreme drought environment of the present invention is carried out according to the following steps:

a. Open parallel ditches on the bare ground in the arid desert area, the ditch depth is 0.4-0.5m, and the distance between the ditch is 2-4m, and then ditches are opened at the beginning and end of each ditch, the ditch depth is 0.4-0.5m, and the flow between the ditches is maintained;

b. During July-October every year, harvest the fruits and seeds of Tamarix, Populus euphratica, licorice, bell thorn and Nitraria, dry them in the shade, and store them in a low-temperature dry environment with paper bags;

c. Use groundwater to flood and store pre-reclamation ditches in April, and use floods to flood the bare ground in arid desert areas from September to October;

d. When irrigating and replenishing water, pour the collected plant seeds into the water flow, and spread the seeds of the species lost in the degraded community through the water flow;

e. In April and September-October of the second year, water replenishment and irrigation are carried out twice to promote the development of plant roots to the deep layer.

Tamarix, Populus euphratica, Radix Glycyrrhiza, Bell thorn and Nitraria described in step b are selected to grow vigorously and have luxuriant flowers and branches, and they are picked while ripening during the fruit ripening period.

The plant seeds described in step b are air-dried based on the cracking of the pericarp, and avoid exposure to the sun.

The rapid method for promoting the ecological recovery of damaged ecosystems in the extremely arid environment of the present invention uses the principle of the locality of biological species to collect the seeds of Populus euphratica, Tamarix, licorice, bell thorn and Nitraria for provenance compensation. In view of the seed maturity period of these native species, from July to October, plants with vigorous growth and luxuriant flowers are selected to collect mature seeds every month, so as to achieve harvesting while ripening and improve the survival rate of seeds. Utilize water storage pressure and salt, open ditches to store water in the area to be restored, and stimulate the seed bank through flood irrigation to improve the breeding habitat of the lost species in the degraded community. Utilize the propagation mode and dispersal law of desert vegetation, and disperse seeds through irrigation to realize provenance compensation in lost species areas.

The rapid method for promoting ecological recovery of damaged ecosystems under the extreme drought environment of the present invention is characterized in that:

The present invention aims at the loss of species in the desert area under the extremely arid environment, and the structure of the plant community tends to be simple and average. By utilizing the natural vegetation composition, community dynamics, reproduction mode and the natural succession process of the desert vegetation community, the artificial ecological restoration and the natural restoration are combined. The combined method accelerates the recovery of desert plants. At the same time, the law of water and salt migration in desert areas and the effect of flood irrigation on the stimulation of seed banks can be used to improve the breeding habitat of lost species in degraded communities, so as to achieve plant provenance compensation and increase the diversity of desert plant communities. stability, increase the stability of the community structure, and thus ensure the long-term effect after the artificial ecological restoration measures are withdrawn.

Compared with the existing auxiliary methods of artificial restoration of vegetation in arid desert areas, it can make full use of the natural restoration process under the natural conditions of extremely low precipitation, large evaporation and deep groundwater depth, with low economic cost and high cost. The technical and operational method improves the purpose of ecological restoration in arid desert areas and avoids the reverse succession of plant communities after artificial restoration.

Detailed ways

Example 1:

On the bare ground in the arid desert area, artificial or mechanical methods are used to open parallel ditches, the ditch depth is 0.4m, and the distance between the ditch is 2m, and 0.4m deep ditches are opened at the beginning and end of each ditch to keep the flow between the ditches. Pre-opening ditches for flood irrigation and water storage;

During the period from July to October each year, in the same area to be restored, select a place where the local species diversity is well maintained, and choose Tamarix, Populus euphratica, licorice, bell thorn and Nitraria plants with vigorous growth and luxuriant flowering branches. Harvest fruits and seeds while they are ripe, and dry them in a windy and shaded place until the skin cracks. Avoid exposure to the sun. Collect them in paper bags and store them in a low-temperature and dry environment;

In September and October (the specific time depends on the amount of water coming in from the Tarim River) the area to be restored will be flooded with flood irrigation, and at the same time, the collected plant seeds will be poured into the water flow to spread the seeds of the species lost in the degraded community through the water flow, and the lost species of plants The determination of seed species is based on the principle of locality, that is, the principle of local sampling and local supplementation. Select areas with better local species diversity to collect seeds, and supplement the source of lost species in areas with damaged ecosystems and single species. ;

In April, September and October of the second year (the specific time depends on the amount of water coming from the Tarim River), water replenishment irrigation should be carried out twice to promote the development of plant roots to the deep layer.

Example 2:

On the bare ground in the arid desert area, artificial or mechanical methods are used to open parallel ditches with a depth of 0.5m and a distance of 3m. Plow 0.5m deep ditches at the beginning and end of each ditch to keep the ditches unimpeded. Reclamation of furrows for flood irrigation and water storage;

During the period from July to October each year, in the same area to be restored, select a place where the local species diversity is well maintained, and choose Tamarix, Populus euphratica, licorice, bell thorn and Nitraria plants with vigorous growth and luxuriant flowering branches. Harvest the fruits and seeds while they are ripe. After harvesting, put them in the shade to dry until the peels crack. Avoid exposure to the sun. Collect them in paper bags and store them in a low-temperature and dry environment;

In September and October (the specific time depends on the amount of water coming in from the Tarim River) the area to be restored will be flooded with flood irrigation, and at the same time, the collected plant seeds will be poured into the water flow to spread the seeds of the species lost in the degraded community through the water flow, and the lost species of plants The determination of seed species is based on the principle of locality, that is, the principle of local sampling and local supplementation. Select areas with better local species diversity to collect seeds, and supplement the source of lost species in areas with damaged ecosystems and single species. ;

In April, September and October of the second year (the specific time depends on the amount of water coming from the Tarim River), water replenishment and irrigation will be carried out twice to promote the development of plant roots to the deep layer.

Example 3:

On the bare ground in the arid desert area, parallel ditches were dug manually or mechanically. The ditches were 0.5m deep and 4m apart, and 0.5m deep ditches were opened at the beginning and end of each ditch to keep the ditches unimpeded. Reclamation of furrows for flood irrigation and water storage;

During the period from July to October each year, in the same area to be restored, select a place where the local species diversity is well maintained, and choose Tamarix, Populus euphratica, licorice, bell thorn and Nitraria plants with vigorous growth and luxuriant flowering branches. Harvest the fruits and seeds while they are ripe. After harvesting, put them in the shade to dry until the peels crack. Avoid exposure to the sun. Collect them in paper bags and store them in a low-temperature and dry environment;

In September and October (the specific time depends on the amount of water coming in from the Tarim River) the area to be restored will be flooded with flood irrigation, and at the same time, the collected plant seeds will be poured into the water flow to spread the seeds of the species lost in the degraded community through the water flow, and the lost species of plants The determination of seed species is based on the principle of locality, that is, the principle of local sampling and local supplementation. Select areas with better local species diversity to collect seeds, and supplement the source of lost species in areas with damaged ecosystems and single species. ;

In April, September and October of the second year (the specific time depends on the amount of water coming from the Tarim River), water replenishment and irrigation will be carried out twice to promote the development of plant roots to the deep layer.

Claims (3)

1. a rapid method for promoting ecological recovery of damaged ecosystems under an extreme drought environment, characterized in that it is carried out in the following steps: a. Open parallel ditches on the bare ground in the arid desert area, the ditch depth is 0.4-0.5m, and the distance between the ditch is 2-4m, and then ditches are opened at the beginning and end of each ditch, the ditch depth is 0.4-0.5m, and the flow between the ditches is maintained; b. During July-October every year, harvest the fruits and seeds of Tamarix, Populus euphratica, licorice, bell thorn and Nitraria, dry them in the shade, and store them in a low-temperature dry environment with paper bags; c. Use groundwater to flood and store pre-reclamation ditches in April, and use floods to flood the bare ground in arid desert areas from September to October; d. When irrigating and replenishing water, pour the collected plant seeds into the water flow, and spread the seeds of the species lost in the degraded community through the water flow; e. In April and September-October of the second year, water replenishment and irrigation are carried out twice to promote the development of plant roots to the deep layer. 2. The method according to claim 1, characterized in that the Tamarix described in step b, Populus euphratica, Radix Glycyrrhiza, Bell thorn and Nitraria are selected to grow vigorously and have luxuriant flower branches, and they are picked while ripening. 3. The method according to claim 1, characterized in that the plant seeds described in step b are air-dried based on the cracking of the pericarp, and avoid exposure to the sun.