Grassland ecological restoration based on the relationship between vegetation and its below-ground habitat analysis in steppe coal mine area.

Coal mining activities have caused severe disturbances to the regional ecosystem and soil properties. Studying the relationship of vegetation and its below-ground habitat (RVBGH) is of great significance to the coal mine land ecological restoration. To identify the optimal thickness of the soil layer for mine land ecosystem recovery and characterize the changes of the reclaimed soil-vegetation ecosystem, we studied natural and reclaimed grassland at the coal mine of Baorixile, located in Hulunbuir Steppe, Northeastern China. The vegetation and its below-ground habitat (BGH), including "root mass" and soil properties in the soil profile (0-100 cm), were surveyed in the natural and different year-reclaimed grassland. The "root mass" is the part of root system that has the most amounts of root hairs, which is the functional zone for plant growth. The RVBGH was identified by the "root mass" and plant water extraction depth, measured through the isotope δD and δ18O method. Firstly, the BGH of natural grassland was identified as a "double layer" vertical structure, with the "root mass" of 37.11 ± 2.57% fine roots at 0-20 cm range and 30.44 ± 2.67% at 20-40 cm range. The annual and perennial plant "root mass" was found at 0-20 cm and 20-40 cm depth, respectively. Secondly, an optimal thickness of the soil covering of 30-40 cm was proposed for grassland reclamation. Thirdly, along the reclamation chronosequence, the values of the reclaimed vegetation properties (height, density, coverage and diversity) increased and a deep root system was established. The "root mass" increased from one layer to double layer and the amount of total fine roots increased from 1621 ± 231.9 to 4459 ± 456.0. Moreover, the reclaimed soil properties of organic matter, cation exchange capacity, available N and P also increased. The study proposed that vegetation restoration was significantly correlated with its BGH, suggesting that vegetation BGH recovery is crucial in ecological restoration.

Groundwater environmental risk assessment of abandoned coal mine in each phase of the mine life cycle: a case study of Hongshan coal mine, North China.

Human activities during each phase of coal mine life cycle greatly affect groundwater environment. The groundwater environment destruction is not just only the destruction of underground structure but also the social problems caused by available groundwater resources reduction, as well as the environmental problems affecting ecosystem and human health. Moreover, the groundwater environmental risk of coal mining is complex, dynamic, and long-term. Therefore, a framework and quantitative method for groundwater environmental risk analysis at different phases of the mine life cycle was presented, which is composed of the groundwater system destruction risk (GSDR) and social-economic-ecological vulnerability (SEEV) assessment. The framework was applied in Hongshan abandoned coal mine, North China. Based on the aquifer structure destruction, groundwater flow field evolution, contamination, and social-economic influence analysis, 12 main controlling factors for the GSDR and 7 factors for the SEEV were determined and quantified separately. The results showed that the groundwater contamination of the Hongshan mine mainly occurred after closure, caused by the cross-strata pollution of mine water, which significantly reduced the groundwater available resources, which greatly affected local social-economy sustainable development and residents' health. The Hongshan mine closure increased groundwater environmental risk, with the GSDR high-risk zone being 12.51 km2 larger than that during the mining phase and the SEEV was calculated at a high level. This framework promotes systematic integration of the groundwater environmental risk assessment in mine life cycle.

[Erythropoietin levels in patients with multiple sclerosis complicated with anemia].

OBJECTIVE: To explore the potential decrease of serum erythropoietin (EPO) level in patients with multiple sclerosis (MS) complicated with anemia. METHODS: The serum EPO levels were detected in the patients with MS complicated with anemia (MS group, n=31), patients with iron deficiency anemia (IDA group, n=33), and healthy subjects (normal control group, n=80) by enzyme-linked immunosorbent assay (ELISA). Blood routine test, reticulocyte count, hemoglobin, and indexes of liver and kidney function were also detected. RESULTS: The serum EPO level in MS group was significantly lower than those in IDA group [(101.3±17.6)U/L vs.(166.1±8.7)U/L, P<0.01]. Moreover, the serum EPO level decreased as the severity of anemia in the MS group increased: it was (95.7±9.6), (101.7±8.1), and (123.7±9.3) U/L in patients with mild, moderate, and severe anemia, respectively (P<0.05). Other indicators including blood routine findings, reticulocyte count, hemoglobin, and liver and kidney function parameters showed no significant difference between the MS group and the IDA group (P>0.05). CONCLUSIONS: The serum EPO level decreases in patients with multiple sclerosis complicated with anemia, and the decreasing levels are related with the severity of anemia. Thus EPO therapy may be beneficial for these patients.