JOURNAL OF NATURAL RESOURCES ›› 2014, Vol. 29 ›› Issue (9): 1531-1541.doi: 10.11849/zrzyxb.2014.09.008

• Resources Evaluation • Previous Articles     Next Articles

Changes of Soil Properties and Water Conservation Function inthe Degradation Process of Gahai Peat Bog in Gannan

MAWei-wei1, WANG Hui1, WANG Yue-si2, HUANG Rong1, SHI Xiao-wei3   

  1. 1. College of Forestry, Gansu Agricultural University, Lanzhou 730070, China;
    2. Institute of Atmospheric Physics, CAS, Beijing 100029, China;
    3. Gahai Zecha Nature Reserve Administration, Luqu 747200, China
  • Received:2013-09-16 Revised:2014-01-24 Online:2014-09-20 Published:2014-09-20

Abstract:

Peat bogs have seriously degraded due to global change and human disturbance andovergrazing of pastures in Gahai wetlands of Gansu Province. Using an approach of spatial sequenceinstead of temporal sequence, the investigations were conducted at four different degradationstages of peat bogs to find out the changing trends of soil properties and water conservationfunctions during the peat bogs degradation. The results showed: With the increase of peatbogs degradation gradient, 1) the average soil bulk density in 0-40 cm soil layers increased continuously,soil total porosity decreased gradually, and they both changed in different soil profiles.2)The value of soil chemical properties containing the soil organic matter, total nitrogen(TN), available potassium (AK) and hydrolysis nitrogen (HN) decreased gradually, ammoniumnitrogen (AN) increased gradually, the contents of total phosphorus and total potassium had nodefinite trend, whereas they were fluctuating changes along the soil profiles. 3) The highest contentsof soil natural moisture, minimum storage and capillary storage were found in the non-degradedpeat bogs, while the lowest were the middle-degraded. The results of variance analysisshowed that the soil bulk density, total porosity, organic matter, AN and water storage capacityhad significant differences among different degradation stages (P<0.05). The soil saturated storageand capillary storage were positively correlated with the soil organic material content (P<0.05), as well as influenced by plant coverage and depth of peat soil indirectly. These results indicatedthat the basically reasons for changes of soil properties and water conservation functionamong degradation process of Gahai peat bogs were the draw down of ground water and the decreasesof plant coverage, soil organic material and peat soil depth.

Key words: Gahai peat bog, water conservation function, soil properties, degradation stages

CLC Number: 

  • S152