Abstract:Taking nine typical measures for controlling rocky desertification in Huajiang karst Canyon of Guanling, Guizhou Province as test objects, including Zanthoxylum bungeanum (HJ), Hylocereus undulatus (HL), Zanthoxylum bungeanum and Hylocereus undulatus (HHL), Pennisetum hydridum (HZ), Medicago sativa (MX), Sabina chinensis (YB), Sabina chinensis and Ligustrum lucidum (YBN), Bare land (LH), and slope farmland (PD), the distribution of organic carbon, total nitrogen, and water-soluble organic carbon in soil profile under different control measures was studied. The results showed that the contents of soil organic carbon, total nitrogen, reserves and water-soluble organic carbon decreased with the increase of soil profile depth in 0-20 cm soil layers, and the phenomena of surface accumulation were obvious. The order of average soil organic carbon and total nitrogen content in 0-20 cm layer was YB > YBN > LH > HJ > MX > PD > HHL > HL > HZ, YBN > YB > LH > PD > MX > HJ > HZ > HHL, respectively. Soil organic carbon, total nitrogen reserves and water-soluble organic carbon content also showed that YB, YBN, and LH were significantly higher than the other six control measures. Soil C/N of each control measure ranged from 7.19 to 16.35. Correlation analysis showed that soil organic carbon content was significantly correlated with soil total nitrogen content, organic carbon storage and soluble organic carbon content. Soil bulk density was the key factor of soil carbon and nitrogen index, and had a good correlation. The study clarifies that in the process of controlling rocky desertification in the future, returning farmland to forest and abandoning desert land will be beneficial to the control and protection of karst ecological environment. Zanthoxylum bungeanum forest can be regarded as the priority economic vegetation type in the process of agricultural production or ecological restoration in Karst Mountainous areas.