Characteristics of seed rain of Haloxylon ammodendron in southeastern edge of Junggar Basin

The Junggar Basin, located in the northern part of Xinjiang Autonomous Region, China, lies at the northern edge of the arid region in northwestern China. The Gurbantuengguet Desert, in the middle of the basin, makes up the main part of the Junggar Basin. The most concentrated populations of Haloxylon ammodendron, an important species for stabilizing desert ecosystems, are in the Junggar Basin. This study looked at seed rain patterns of this species in the southeastern edge of the Junggar Basin. Precipitation rarely occurs in this area of high temperatures. This basin is mainly composed of fixed and semi-fixed sand dunes so the natural environment of this species is quite fragile. H. ammodendron is a special desert shrub which grows larger than other desert shrubs. It is the most important native species here and is very well adapted a variety of harsh desert environments. This key species is widely distributed in gaps between the fixed and semi-fixed sand dunes and also grows into the lower part of the fixed and semi-fixed sand dunes and even forms pure forest. The local desert vegetation dominated by H. ammodendron, called H. ammodendron forest, provides a green barrier which benefits local economic and social development, and has significant effects on maintaining and stabilizing the local desert ecosystem. The key to sustainably maintaining and developing local desert vegetation is achieving natural regeneration of H. ammodendron. The seed is both the starting and end point of the plant life cycle. The stage at which seed rain occurs, an important phase of the plant life cycle, is the key link to natural regeneration, directly impacting the spread of plant seeds and decisively influencing seed germination, seedling survival, plant growth and a series of ecological processes. The seed rain of H. ammodendron on the southeastern edge of the Junggar Basin was studied by laying seed rain traps and using laboratory experiments. The aim was to survey the temporal dynamics and spatial distribution of seed rain to determine the laws and factors impacting seed dispersal. This study focused on the quality and quantity of seeds during different phases of seed rain. The results show (1) the cumulative annual seed rain intensity reached 189 seeds/m super(2), although in some small local environments it reached as high as 2413 seeds/m super(2) with viable seed comprising 80% of the total seed rain. (2) The peak period of seed rain was early November, producing 65% of