Particularly concerned is a method of planting walnut trees in wetland vanishing zones using grafting techniques
The fading zone, also known as the fading zone or the ebb and flow zone, is a phenomenon unique to rivers, lakes and reservoirs, and its formation is mainly due to the seasonal rise and fall of the water level and the periodic exposure of the flooded land around the reservoir area to a special area on the water surface. This area is a dry and wet alternating zone, but also the most active area between the water and land ecological environment of matter, energy, information transmission and conversion, in the biogeochemical cycle has the "source", "reservoir", "transfer station", "regulator" function, is the reservoir area between the land and water area of the ecological transition zone, but also the ecological environment changes drastically and unstable ecological fragile zone, the water, land, especially the ecological environment on both sides of the reservoir area have a major impact, is the reservoir, rivers, lakes and other water body ecological environment in the key subsystem.
Affected by the cyclical fluctuation of water level in the reservoir area, the fading zone is an active zone for the transport and transformation of energy and materials in the ecosystem of the reservoir area, which has a strong ecological function of interception from farmland runoff and non-point source pollution (nitrogen, phosphorus, carbon), which is conducive to the retention, enrichment and degradation of organic pollutants, and plays an important role in improving water quality, purifying sewage, improving fish and wildlife habitats, protecting biodiversity and developing fishery production, and the fading zone is also a transportation port, freshwater resources and tourist destination. It is an important living environment for the people in the reservoir area. Therefore, the fading zone is not only a land resource with multiple functions, but also a resource with high buffer capacity and environmental purification and protection functions.
The fading zone is a valuable resource with a variety of functions. As part of the reservoir, the large number of aquatic plants with good water holding performance in the fading zone has a huge protective effect on suppressing floods and preventing soil erosion caused by heavy rainstorms and water flows washing the riverbank; and during the period of retreat into land, the fading zone has great agricultural development and utilization value. Vegetation development in the fading zone is crucial to the function of the fading zone.
At present, the plant planting in the sedimentary fading zone of the reservoir area mainly has the following problems: the environmental conditions for the growth of plants in the fading zone are relatively harsh, and it is necessary to endure the stress of environmental factors such as flooding, glare, drought, and lack of nutrients, so there are very few plant species in nature that are suitable for the growth of amphibian special habitats in the fading zone, and it is difficult to screen; even if the suitable plant species are screened, but because the soil structure in the fading zone is eroded by long-term water flow, the soil organic matter dissolves into the water body in large quantities, resulting in the deterioration of the water quality in the reservoir area, and the soil organic matter is low. It is difficult for the selected pioneer species to obtain sufficient nutrients to continue their survival in the early stage of settlement, and it is difficult for individual plants to form stable vegetation communities in the fading zone even if transplanted successfully.
Therefore, a simple, rapid and effective method for rapid cultivation of cash crops in the fading zone of the reservoir area is constructed to form a stable vegetation community in the fading zone, reduce the negative effects of soil erosion on the environment, reduce or control environmental pollution and increase the value of agricultural development and utilization.
Walnut, also known as walnut, is a deciduous tree of the walnut family Walnut family, ranked first among the world's four major dried fruits (walnuts, almonds, cashews, hazelnuts), known as the "king of woody oilseeds", is one of the main economic forest species in China, with high nutritional value and good health care effects. However, the resistance of walnut tree species to cold and drought is weak, and it is not tolerant of moisture and waterlogging, and its resistance to disease is weak, resulting in the inability to plant in the fading zone of the reservoir area.
Maple poplar, also known as water hemp willow, maple willow, centipede willow, ghost head poplar and yuanbao poplar, etc., is a large deciduous tree of the genus Maple poplar in the family Walnut family, with a height of up to 30 meters, a chest diameter of up to 1 meter, and a flattened spherical crown; the soil requirements are not strict, and can grow in acidic and slightly alkaline soils. It prefers warm and humid climates and thick and fertile soils, and is drought-tolerant and barren, and water-tolerant. Young trees grow fast, with a rapid growth period lasting about 15 years, after which the growth gradually slows down. It is an important afforestation tree species in the plain lake area, low mountain valleys and river banks, and is also an urban greening tree species. Maple poplar has a strong resistance to toxic gases such as soot and sulfur dioxide, and the wood is white and soft, and can be used as furniture and matchsticks, etc., and can also be used as walnut rootstock. Maple leaves contain 2-pentanol, b- cnidine, b- red myrrh alkene, cetanoic acid and b- glutanol and other compounds, its bark, leaves, fruits, roots and other parts can be medicated, with insecticidal antipruritic, detoxification and pain relief and other effects, maple poplar and walnut in different genera of the same family, with maple poplar grafting walnut can avoid cross-infection of diseases on the same plant, enhance the disease resistance of plants.
(1) Planting site selection
Select the area of the fading zone with a rise and fall depth of < 20 m, a slope of < 30°, a land exposure time of 3-mid-May, and a total land exposure time of 190-270d as the land to be planted;
(2) Land consolidation
In the middle of March to Mid-May, the land to be planted is exposed, dried for 3-5 days for land consolidation, the land is prepared in the cave shape before planting, the length, width and depth of the whole planting hole are 60-80 cm, the row spacing of the planting hole plants is 1.5-2.0m×2.0-3.0m, the base fertilizer is applied at the bottom of the hole, the base fertilizer is organic fertilizer, grass and wood ash, and the soil is mixed according to the ratio of weight to 1-5:1-5:1-2, the organic fertilizer is dried chicken manure or decomposed fermented cow manure or horse manure, The soil is the powdery soil obtained by drying, crushing and passing through a 20-60 mesh sieve of the planting ground;
(3) Maple poplar planting
Among them, after the completion of the land consolidation in (2), in 3-5 months, select the robust, disease-free and pest-free more than 1 year of maple poplar seedling transplanting, the strong seedling with the planting, planting the main root of the seedling according to the size of the planting hole appropriately short, so as not to nest roots, pruning tools should be sharp, smooth incision, to avoid tearing the root bark; after maple poplar planting, should be covered with straw around the base of the trunk, at the same time, according to the weather conditions for irrigation, should keep the soil moist without water;
(4) Nursing management
After maple poplar planting, 3-4 weeding and loosening of soil were carried out in May-September of the same year, and 2-3 times of topdressing in June-July of the same year, each time the organic fertilizer was applied 500-600kg/hm2; the irrigation was stopped after the end of August; phosphorus and potassium fertilizer were applied in September, each 500-700kg/hm2, turned into the soil; the organic fertilizer was dried chicken manure or decomposed fermented cow and horse manure;
(5) Walnut grafting
Walnut grafting is carried out in April-May of the second year after planting, 5-10 days before grafting, watered once a day; select 1 year old, robust and full walnut scion, cut the walnut scion into three shaved surfaces, and carry out high grafting in the part of the maple poplar tree above 1.8 meters, after grafting, the interface between the scion and the maple poplar rootstock is tightly bandaged with plastic film, and the plastic film is removed after 15-20 days; within 10 days after grafting, it needs to be watered once a day; after 15 days, the bandaging film is removed, and then routine management can be carried out. After grafting, it is necessary to check frequently to remove the buds on the rootstock in time to promote the development and growth of the buds. If there are mulberry caterpillars, leaf beetles and other young leaves that eat young shoots after germination, 40% Lego Emulsion 1000 times liquid spray can be used. When some trees are found with black spot disease, a 50% wettable tolbutzin 800 times liquid spray is used.
(6) Management of walnuts after grafting
After walnut grafting, 3-4 times of weeding and loosening of soil are carried out in May-September of each year, 2-3 times of topdressing in June-July, 500-600kg/hm2 of organic fertilizer is applied each time, irrigation is stopped after late August, phosphorus and potassium fertilizer are applied 500-700kg/hm2 in September, turned into soil, phosphorus and potassium fertilizer are applied again in October-November 500-700kg/hm2 each, turned into the soil, and the soil surface is pressed tightly; the organic fertilizer is dried chicken manure or decomposed fermented cow manure or horse manure Other times for regular management can be done.
Wherein (2), the base fertilizer is organic fertilizer, grass and wood ash, soil according to the ratio of 2: 1.5 : 1 mixed by weight.
Wherein (2), the soil is the soil of the planting area by drying, crushing, through the 50 mesh sieve obtained by the powdery soil.
Among them, in (3), in March-May, select robust, disease- and pest-free 2-3 year old maple poplar seedlings transplanted.
Of the (5), select April-May sunny days for walnut grafting.
In (5), the walnut scion is cut into three facets and grafted high on the part of the maple poplar tree 1.8-2.5 meters.
Among them, in (5), when walnuts are grafted, they are torn with a diameter of more than 6 cm, and cut with a diameter of less than 6 cm.
Among them, (6), when the grafted walnut tree begins to bear fruit, in late August of each year, a plastic net is pulled under the canopy of the walnut tree to prevent the fruit from falling into the water.
