European forestry is facing many challenges, including the need to adapt to climate change and an unprecedented increase in forest damage. We investigated these challenges in a Norway spruce-dominated mountain region in Central Europe. We used the model Sibyla to explore forest biomass production to the year 2100 under climate change and under two alternative management systems: the currently applied management (CM), which strives to actively improve the forest’s adaptive capacity, and no management (NM) as a reference. Because biodiversity is thought to have mostly positive effects on the adaptive capacity of forests and on the quality of ecosystem services, we explored how climate change and management affect indicators of biodiversity. We found a differential response across the elevation-climatic gradient, including a drought-induced decrease in biomass production over large areas. With CM, the support of non-spruce species and the projected improvement of their growth increased tree species diversity. The promotion of species with higher survival rates led to a decrease in forest damage relative to both the present conditions and NM. NM preserved the high density of over-matured spruce trees, which caused forest damage to increase. An abundance of dead wood and large standing trees, which can increase biodiversity, increased with NM. Our results suggest that commercial spruce forests, which are not actively adapted to climate change, tend to preserve their monospecific composition at a cost of increased forest damage. The persisting high rates of damage along with the adverse effects of climate change make the prospects of such forests uncertain. 相似文献
我国本土水生生物稀有鮈鲫(Gobiocypris rarus Ye et Fu,1983年)是一种优良的试验用鱼,具备成为模式生物必要条件。本文总结了稀有鮈鲫生物生态学研究情况,分析了稀有鮈鲫在多个应用领域与模式生物斑马鱼、青鳉存在的不足和差距,同时借鉴发达国家推动模式生物的实践经验,提出了针对性建议。 相似文献
This paper studied the biofilm properties and corrosion behavior of sulfate reducing bacteria (SRB) on stainless steel 316L (SS316L) surface in circulating cooling water system with and without additives including hydroxy ethyl fork phosphonic acid (HEDP), dodecyl dimethyl benzyl ammonium chlotide (1227) and NaClO. Biochemical technique, electrochemical technology, X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM) were used. The results show that the extracellular polymeric substance (EPS) in biofilm attached on the SS316L surface mainly contain proteins and polysaccharides, the contents are 98 ug·cm-2 and 635ug·cm-2, respectively. The polysaccharides were cut by 1227 about 80%, while 55% by NaClO. The proteins were reduced by NaClO about 53%, while only 30% by 1227. The potentiodynamic polarization shows that the corrosion potential of SS316L was enhanced from -0.495 V to -0.390 V by the chemical additives, delaying the occurrence of the corrosion. And the corrosion rate was also reduced from 5.19 × 10-3 mm·a-1 to 2.42 × 10-3 mm·a-1. But NaClO still caused pitting corrosion after sterilizing the bacteria, while 1227 can form a protective film on the surface of SS316L. Though HEDP contribute to the bacteria activity, it can enhance the breakdown potential. XPS results confirmed that 1227 can change the value of C:O in the biofilm attached on metal surface, and NaClO can eliminate the existence of amidogen. This study would provide some recommendations for the selection of chemical additives in the thermal power plant.
The fate of 14C-labeled sulfadiazine (14C-SDZ) residues was studied in time-course experiments for 218 days of incubation using two soils (Ap horizon of loamy sand, orthic luvisol; Ap horizon of silt loam, cambisol) amended with fresh and aged (6 months) 14C-manure [40 g kg?1 of soil; 6.36 mg of sulfadiazine (SDZ) equivalents per kg of soil], which was derived from two shoats treated with 14C-SDZ. Mineralization of 14C-SDZ residues was below 2% after 218 days depending little on soil type. Portions of extractable 14C (ethanol-water, 9:1, v/v) decreased with time to 4–13% after 218 days of incubation with fresh and aged 14C-manure and both soils. Non-extractable residues were the main route of the fate of the 14C-SDZ residues (above 90% of total recovered 14C after 218 days). These residues were high immediately after amendment depending on soil type and aging of the 14C-manure, and were stable and not remobilized throughout 218 days of incubation. Bioavailable portions (extraction using CaCl2 solution) also decreased with increasing incubation period (5–7% after 218 days). Due to thin-layer chromatography (TLC), 500 μg of 14C-SDZ per kg soil were found in the ethanol-water extracts immediately after amendment with fresh 14C-manure, and about 50 μg kg?1 after 218 days. Bioavailable 14C-SDZ portions present in the CaCl2 extracts were about 350 μg kg?1 with amendment. Higher concentrations were initially detected with aged 14C-manure (ethanol-water extracts: 1,920 μg kg?1; CaCl2 extracts: 1,020 μg kg?1), probably due to release of 14C-SDZ from bound forms during storage. Consistent results were obtained by extraction of the 14C-manure-soil samples with ethyl acetate; portions of N-acetylated SDZ were additionally determined. All soluble 14C-SDZ residues contained in 14C-manure contributed to the formation of non-extractable residues; a tendency for persistence or accumulation was not observed. SDZ's non-extractable soil residues were associated with the soluble HCl, fulvic acids and humic acids fractions, and the insoluble humin fraction. The majority of the non-extractable residues appeared to be due to stable covalent binding to soil organic matter. 相似文献
Ji, Yuhe, Liding Chen, and Ranhao Sun, 2012. Temporal and Spatial Variability of Water Supply Stress in the Haihe River Basin, Northern China. Journal of the American Water Resources Association (JAWRA) 48(5): 999‐1007. DOI: 10.1111/j.1752‐1688.2012.00671.x Abstract: Water resources are becoming increasingly stressed under the influence of climate change and population growth in the Haihe River Basin, Northern China. Assessing the temporal and spatial variability of water supply stress is urgently needed to mitigate water crisis caused by water resource reallocation. Water supply and use data were compiled for the time period of 1998‐2003 in this synthesis study. The Water Supply Stress Index (WSSI) as defined as Water Demand/Water Supply was used to quantitate whether water supply could meet the demand of human activities across the study region. We found a large spatial gradient of water supply stress in the study region, being much higher in the eastern subbasins (ranging from 2.56 to 4.31) than the west subbasins (ranging from 0.56 to 1.92). The eastern plain region not only suffered more serious water supply stress but also had a much higher interannual variability than the western hilly region. The uneven spatial distribution of water supply stress might result from the distribution of land use, population, and climate. Future climate change and rapid economic development are likely to aggravate the existing water crisis in the study region. 相似文献