Study on the Carbon Storage and Fixation of Phramites autralis in Baiyangdian Demonstration Area

Reed-mushroom-fertilizer ecological agriculture in wetlands: Harvesting reed to cultivate mushroom and returning waste substrates to restore saline-alkaline marshes

Construction of wetland ecological agriculture is recommended to perform ecological function and produce considerable economic value. A mode of wetland ecological agriculture was established on inland saline-alkaline marshes in Northeast of China here. This study used reed as substrate to cultivate Pleurotus citrinopileatus and return the waste substrate (SMS) to ameliorate the saline-alkalized soil. The biological efficiency of mushroom was 69.01 %, and the contents of sugar, crude protein, crude fat, and amino acids were 30.82 %, 23.07 %, 1.58 %, and 19.48 %, respectively in P. citrinopileatus. The cultivated mushrooms had higher contents of Ca, Fe, Zn and Cu, with lower levels of harmful heavy metals. When compared with initial substrates, the SMS remained 93.42 % fiber, 87.08 % carbon, 97.72 % nitrogen, 51.35 % phosphorus, and more Ca contents. Compared with the control, SMS application decreased the soil pH and electro-conductivity by 12.33 % and 30.75 %, and increased total nitrogen and organic matter by 34.98 % and 46.55 %, respectively. In addition to the soil improvements, the above- and belowground biomasses of reed were increased by 172.92 % and 59.64 %, respectively. The study indicated that reed could be used as mushrooms substrates, subsequently applied SMS to ameliorate the saline-alkaline soil. Our wetland ecological agriculture mode of "reed-mushroom-fertilizer" is available and effective for saline-alkaline wetland functioning and economic development.

Factors Affecting Wetland Loss: A Review

Despite occupying an area no greater than 8% of the earth’s surface, natural wetland ecosystems fulfill multiple ecological functions: 1. Soil formation and stabilization support, 2. Food, water, and plant biomass supply, 3. Cultural/recreational services, landscape, and ecological tourism, 4. Climate regulation, and 5. Carbon sequestration; with the last one being its most important function. They are subject to direct and indirect incident factors that affect plant productivity and the sequestration of carbon from the soil. Thus, the objective of this review was to identify the incident factors in the loss of area and carbon sequestration in marine, coastal, and continental wetlands that have had an impact on climate change in the last 14 years, globally. The methodology consisted of conducting a literature review in international databases, analyzing a sample of 134 research studies from 37 countries, organized in tables and figures supported by descriptive statistics and content analysis. Global results indicate that agriculture (25%), urbanization (16.8%), aquaculture (10.7%), and industry (7.6%) are incident factors that promote wetlands effective loss affecting continental wetlands more than coastal and marine ones. Regarding carbon sequestration, this is reduced by vegetation loss since GHG emissions raise because the soil is exposed to sun rays, increasing surface temperature and oxidation, and raising organic matter decomposition and the eutrophication phenomenon caused by the previous incident factors that generate wastewater rich in nutrients in their different activities, thus creating biomass and plant growth imbalances, either at the foliage or root levels and altering the accumulation of organic matter and carbon. It is possible to affirm in conclusion that the most affected types of wetlands are: mangroves (25.7%), lagoons (19.11%), and marine waters (11.7%). Furthermore, it was identified that agriculture has a greater incidence in the loss of wetlands, followed by urbanization and industry in a lower percentage.