Response of Grasshopper and Grasshopper Diversity to Different Grassland Types Under Enclosure Conditions

Enclosure is one of the important methods used to restore grassland ecosystems. Locusts and grasshoppers are important components of grassland ecosystems and can accurately reflect changes in their habitats. However, currently, the response in abundance of grassland locusts and grasshoppers within short-term enclosure mode remains unclear. In this study, a 3-year short-term enclosure experiment on a natural grassland in Ili Kazak Autonomous Prefecture, Xinjiang, China, aimed to explore the response patterns of grassland locusts under fences. According to the results of this study, there were significant differences in the diversity of locusts and grasshoppers in various grassland types after short-term captivity. Canonical Correlation Analysis shows that temperature is the main factor affecting grassland locusts at different altitudes and latitudes; annual precipitation and relative humidity are the main factors affecting the distribution of dominant locusts and grasshoppers in different grassland types; the duration of sunshine and the highest daily temperature are the main factors affecting the dominance of locusts and grasshoppers at different altitudes and latitudes. As altitude increased from the temperate desert steppes to the mountain meadows, vegetation cover presented a "decreasing-increasing" trend, and the number of locusts and grasshoppers per unit quadrat showed a "decreasing-increasing-decreasing" trend. As a result of increased vegetation cover and altitude and decreased latitude, the community structure of locusts and grasshoppers shifted from a decrease in terricoles species such as the Sphingonotus species to an increase in phytophilous species like Omocestus petraeus. In contrast to the results of a study performed in the same area 40 years ago, this survey showed that four species of locusts and grasshoppers, including Gomphocerus sibiricus, shifted toward higher altitudes, causing changes in the community structure of locusts and grasshoppers at higher altitudes; Stauroderus scalaris scalaris replaced Gomphocerus sibiricus and evolved into a high-altitude dominant species; and Pararcyptera microptera microptera shifted toward low altitudes. Therefore, in order to more accurately assess the restoration status of grassland ecosystems under fences, it is necessary to consider the diversity changes and influencing factors of locusts and grasshoppers, which may vary depending on different grassland types.