Revegetation pattern affecting accumulation of organic carbon and total nitrogen in reclaimed mine soils.

Selecting optimal revegetation patterns, i.e., patterns that are more effective for soil organic carbon (SOC) and total nitrogen (TN) accumulation, is particularly important for mine land reclamation. However, there have been few evaluations of the effects of different revegetation patterns on the SOC and TN in reclaimed mine soils on the Loess Plateau, China. In this study, the SOC and TN stocks were investigated at reclaimed mine sites (RMSs), including artificially revegetated sites (ARSs) (arbors (Ar), bushes (Bu), arbor-bush mixtures (AB), and grasslands (Gr)) and a natural recovery site (NRS), as well as at undisturbed native sites (UNSs). Overall, the SOC and TN stocks in the RMSs were lower than those in the UNSs over 10-13 years after reclamation. The SOC stocks in the RMSs and UNSs only differed in the top 0-20 cm of the soil (p < 0.05). Except for those in Ar, the SOC and TN stocks in the ARSs were significantly larger than those in the NRS (p < 0.05). Compared with those in the NRS, the total SOC stocks in the 100 cm soil interval increased by 51.4%, 59.9%, and 109.9% for Bu, AB, and Gr, respectively, and the TN stocks increased by 33.1%, 35.1%, and 57.9%. The SOC stocks in the 0-100 cm soil interval decreased in the order of Gr (3.78 kg m-2) > AB (2.88 kg m-2) ≥ Bu (2.72 kg m-2), and the TN stocks exhibited a similar trend. These results suggest that grasslands were more favorable than woodlands for SOC and TN accumulation in this arid area. Thus, in terms of the accumulation of SOC and TN, grassland planting is recommended as a revegetation pattern for areas with reclaimed mine soils.

Expression of MAC30 in rectal cancers with or without preoperative radiotherapy.

OBJECTIVE: Meningioma-associated protein (MAC30) is overexpressed in several types of cancers, but its therapeutic implication in the patients has not been studied. We examined the relationship of MAC30 with clinicopathological and biological factors in rectal cancer patients with or without radiotherapy (RT). METHODS: MAC30 was immunohistochemically examined in 75 distant and 91 adjacent normal mucosa specimens, 132 primary tumours and 39 lymph node metastases from rectal cancer patients participating in a clinical trial of preoperative RT. RESULTS: In the RT group, MAC30 was or tended to be positively correlated with infiltrated growth pattern (p = 0.02), PRL (phosphatase of regenerating liver, p = 0.01) and Ki-67 expression (p = 0.06). MAC30 at the invasive margin of the metastasis was related to poor survival (p = 0.02) in the whole group of patients. MAC30 in primary tumours was not related to recurrence and survival in the non-RT or RT group. CONCLUSIONS: MAC30 expression in metastasis was an indicator for poor survival. After RT, MAC30 seemed to be more related to aggressive morphological and biological factors; however, we did not find direct evidence that MAC30 expression was related to the outcome of patients with or without RT.