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Annual mass balance is an important reflection of glacier status that is also very sensitive to climate fluctuations. However, there is no effective and universal albedo-based method for the reconstruction of annual mass balance due to the scarcity of field observations. Here, we present an improved albedo–mass balance (IAMB) method to estimate annual glacier surface mass balance series using remote sensing techniques. The averaged glacier-wide albedo derived with the MODImLab algorithm during the summer season provides an effective proxy of the annual mass change. Defined as the variation in the albedo as a function of elevation change, the altitude–albedo gradient ( ∂ z / ∂ α ) can be obtained from a glacier digital elevation model (DEM) and optical images. The Chhota Shigri glacier situated in the western Himalayas was selected to test and assess the accuracy of this method over the period from 2003 to 2014. Reconstructed annual mass budgets correlated well with those from the observed records, with an average difference and root mean square error (RMSE) of −0.75 mm w.e. a−1 and 274.91 mm w.e. a−1, respectively, indicating that the IAMB method holds promise for glacier mass change monitoring. This study provides a new technique for annual mass balance estimation that can be applied to glaciers with no or few mass balance observations. [ABSTRACT FROM AUTHOR]

Agricultural soil organic carbon (SOC) plays a critical role in soil ecosystems, and SOC sequestration is a key ecosystem service. This study investigated the SOC fractions, including mineral‐incorporated organic carbon (MSC), intra‐particulate organic carbon (iPOC) and microbial biomass carbon (MBC), in bulk soil and water‐stable aggregates, as influenced by soil fertilization managements, using three treatments: no fertilizer (CK), chemical fertilizer (FR) and organic manure (OM). Fertilizer application significantly increased SOC content and its fractions (MSC, iPOC and MBC) compared to CK, and the effect of organic manure amendment had more impact on the SOC accumulation than chemical fertilizer. Macroaggregate (>250 μm)‐associated SOC, MSC and iPOC (including fine and coarse iPOC) increased by 22%–283%, 18%–84% and 45%–232%, respectively, in FR and OM treatments compared with CK. In addition, the iPOC:MSC ratio values (%) within all size aggregates were all increased in the FR (about 84%–183%) and OM (about 103%–230%) treatments compared to CK (about 65%–146%). Meanwhile, MBC:SOC ratio values were the highest (about 2.16%–3.07%) in small macroaggregates (250–2000 μm), but decreased sharply (about 2%–2.35%) in large macroaggregates (>2000 μm) in different treatments. Our findings suggested that macroaggregates were the main sites of carbon sequestration and that carbon became more unstable with the increase of SOC in aggregates. Furthermore, the microbial biomass showed obvious differentiation characteristics in macroaggregates (>250 μm). Specifically, small macroaggregates (250–2000 μm) contained more microbial biomass, and large macroaggregates (>2000 μm) were inclined to inhibit microbial activity. [ABSTRACT FROM AUTHOR]

Poly(ethylene terephthalate) (PET) is one of the most commonly used plastics worldwide and its accumulation in the environment is a global problem. PETase from Ideonella sakaiensis 201-F6 was reported to exhibit higher hydrolytic activity and specificity for PET than other enzymes at ambient temperature. Enzymatic degradation of PET using PETase provides an attractive approach for plastic degradation and recycling. In this work, extracellular PETase was achieved by Escherichia coli BL21 using a Sec-dependent translocation signal peptide, pelB, for secretion. Furthermore, engineering of the pelB through random mutagenesis and screening was performed to improve the secretion efficiency of PETase. Evolved pelB enabled higher PETase secretion by up to 1.7-fold. The improved secretion of PETase led to more efficient hydrolysis of the PET model compound, bis (2-hydroxyethyl) terephthalic acid (BHET), PET powder, and PET film. Our study presents the first example of the increasing secretion of PETase by an engineered signal peptide, providing a promising approach to obtain extracellular PETase for efficient enzymatic degradation of PET.