Abstract:
ObjectiveUnder the background of ecological restoration and reconstruction of earthquake-affected areas in southwestern China, exploring the characteristics of vegetation coverage, plant community species diversity, biomass change and six major mineral element contents, and plant carbon (C), nitrogen (N), phosphorus (P) stoichiometry will help to fully understand the dynamic process of vegetation restoration in the earthquake-affected areas.
MethodThe destroyed and treated plots and the undestroyed plots (control group) of Wenzhou Town (arid-valley climate region) in Wenchuan County and Hanwang Town (subtropical monsoon climate region) in the Mianzhu City of typical area of the severely affected Wenchuan earthquake were studied. The vegetation restoration and the main elements and their stoichiometric characteristics of different organs of the plant in the destroyed and treated area (DTA) and the undestroyed area (UA) were analyzed.
Result(1) The vegetation restoration rate in the subtropical monsoon climate region (65.74%) was higher than that in the arid-valley climate region (50.68%), and the coefficient of variation of DTA in the arid-valley climate region and subtropical monsoon climate region was 40.44% and 23.06%, respectively, which was higher than UA by 14.49% and 8.62%. (2) Only stem biomass of plant organs showed significant difference between DTA and UA in two climate regions (P < 0.05). Only leaf carbon content in plant organs showed that DTA was significantly larger than UA in the arid-valley climate region (P < 0.05); (3)The element content in different plant organs was mainly N>K>Ca>Mg>P>Na; (4)Through the leaf nitrogen-phosphorus ratio (N:P), it was found that the DTA and UA in arid-valley climate region were mainly restricted by phosphorus (P), while the DTA and the UA in subtropical monsoon climate region were mainly restricted by nitrogen (N).
ConclusionThe above research shows that climate may be the dominant factor affecting vegetation restoration, and limited nutrient factors affecting vegetation and soil restoration should be fully considered. The research results can provide a scientific basis for the restoration and reconstruction of ecological functions in the earthquake-affected areas in southwestern China.