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S158; 有机碳氮是影响陆地生态系统的重要因子,保持并提高土壤碳氮储量,是稳定生态系统生产力的关键.以南京紫金山土壤为研究对象,依照海拔高度进行采样,对比分析了土壤有机碳氮的变化规律.研究结果表明:紫金山土壤有机碳氮受地表植被的影响比较大,混交林＞林地＞草地,土壤有机碳氮总量随海拔的升高呈现上升趋势,土壤碳氮比高达34 ～ 45,且随海拔升高呈下降趋势.相关分析表明,紫金山土壤有机碳与全氮质量分数呈显著正相关关系,由此说明氮素主要以有机氮的形式存在于有机质中.

目的 为制定中国男性新生儿血红蛋白参考值的统一标准提供科学依据。方法 收集了中国78个单位用氰化高铁血红蛋白(HiCN)法测定的5169例健康男性新生儿血红蛋白参考值，用曲线回归分析的方法研究了其与海拔高度之间的关系。结果 发现随着海拔高度的逐渐增大，男性新生儿血红蛋白参考值也在按指数律逐渐的增大，相关性很显著(R=0．601，F=43．05，P=0．0000)；推导出了一个指数曲线模型Y2=176．9e^0.00008662x±25．3。结论 如果知道了中国某地的海拔高度，就可以用这个指数曲线模型计算这个地区的男性新生儿血红蛋白参考值。依据男性新生儿血红蛋白参考值与地理因素的依赖关系把中国分为青藏区、中部区、东部区3个区。

目的 为制定中国老年女性血沉正常参考值的统一标准提供科学依据。方法 收集了中国202个单位用温氏法测定的11783例健康老年女性血沉正常参考值，用曲线回归分析的方法研究了其与海拔高度之间的关系。结果 发现随着海拔高度的逐渐增大，老年女性血沉正常参考值按指数律在逐渐的减少，相关性很显著(R＝0．701)；推导出了一个曲线回归模型Y＝25．98de^-0.000301x±5.31。结论 如果知道了中国某地的海拔高度，就可以用该回归模型估算这个地区的老年女性血沉正常参考值。依据老年女性血沉正常参考值与地理因素的依赖关系把中国分为青藏区、中部区、东部区等三个区。

This study analyzed the trends in extreme high temperature in Southwest China based on the observed daily maximum temperature and average temperature data from 410 Chinese stations recently released by the China Meteorological Administration. The authors found that the trends in extreme high temperature at different altitudes of Southwest China exhibit staged variations during a recent 50-year period (1961-2014). The trends in mean temperature and maximum temperature also exhibit phase variation. All temperature-related variables increase gently during the period 1975-94, whereas they increase dramatically during the recent period of 1995-2014, with a rate that is approximately two to ten times more than that during 1975-94. In addition, the trends in mean temperature, maximum temperature, and the frequency of extreme high temperature in the low altitudes transit from negative to positive in the two periods, while they increase dramatically in the mid- and high-altitude areas during 1995-2014, the well-known global warming hiatus period. In particular, the maximum temperature increases much faster than that of average temperature. This result implies that the regional temperature trend could be apparently different from the global mean temperature change.

A two-dimensional coupled tide-surge model was used to investigate the effects of tide-surge interactions on storm surges along the coast of the Bohai Sea, Yellow Sea, and East China Sea. In order to estimate the impacts of tide-surge interactions on storm surge elevations, Typhoon 7203 was assumed to arrive at 12 different times, with all other conditions remaining constant. This allowed simulation of tide and total water levels for 12 separate cases. Numerical simulation results for Yingkou, Huludao, Shijiusuo, and Lianyungang tidal stations were analyzed. Model results showed wide variations in storm surge elevations across the 12 cases. The largest difference between 12 extreme storm surge elevation values was of up to 58 cm and occurred at Yingkou tidal station. The results indicate that the effects of tide-surge interactions on storm surge elevations are very significant. It is therefore essential that these are taken into account when predicting storm surge elevations.

Topography, especially altitude, will influence the way, process and characteristics of land cover changes in mountainous area, simultaneously, the vertical difference of land cover changes will affect soil quality and regional ecological environment. Therefore, the gradient relationship analysis between land cover changes and altitude is very important for regional sustainability. This study investigated land cover dynamics based on land cover data from a typical mountainous area in the Guizhou-Guangxi karst mountain area, China, in 2000 and 2010, then explored the relationship between altitude and land cover change and analyzed different drivers of land cover change at different altitudes. Our findings are as follows. 1） From 2000 to 2010, the total area of land cover transition was 7167.04 km~2 or 2.8% of the region. The increasing area of build-up land（926.23 km~2） was larger than that of forest（859.38 km~2）, suggesting that the urban construction speed was higher than that of reforestation. 2） Intensity of land cover transition in northwestern Guizhou-Guangxi karst mountain area was much larger than that of southeast part and their transition trend was also significantly different, which was consistent with regional population and economy. 3） Human activity was the most dramatic at altitudes between 0–500 m. For 500–1000 m, grassland mainly converted to forest and build-up land. Area of land cover transition was the greatest between 1000–1500 m, while above 1500 m, the transition of grassland was the most obvious. 4） The drivers of land cover change varied. Land cover change was positively correlated with gross domestic product and population density but was inversely related to relief amplitude. There were correlations between land cover change and distance to roads and rivers, and their correlations varied with altitude. By revealing patterns and causes of land cover changes in different altitudes, we hope to understand the vertical dependence of land cover changes, so as to improve land productivity and protect land ecological environment scientifically.

Stable isotope paleoaltimetry has provided unprecedented insights into the topographic histories of many of the world＇s highest mountain ranges. However, on the Tibetan Plateau（TP）, stable isotopes from paleosols generally yield much higher paleoaltitudes than those based on fossils. It is therefore essential when attempting to interpret accurately this region＇s paleoaltitudes that the empirical calibrations of local stable isotopes and the relations between them are established. Additionally,it is vital that careful estimations be made when estimate how different isotopes sourced from different areas may have been influenced by different controls. We present here 29 hydrogen isotopic values for leaf wax-derived n-alkanes（i.e., δD_（wax） values,and abundance-weighted average δD values of C_（29） and C_（31）） in surface soils, as well as the δD values of soil water（δD_（sw）） samples（totaling 22） from Mount Longmen（LM）, on the eastern TP（altitude ~0.8–4.0 km above sea level（asl）, a region climatically affected by the East Asian Monsoon（EAM）. We compared our results with published data from Mount Gongga（GG）. In addition,47 river water samples, 55 spring water samples, and the daily and monthly summer precipitation records（from May to October,2015） from two precipitation observation stations were collected along the GG transect for δD analysis. LM soil δD_（wax） values showed regional differences and responded strongly to altitude, varying from.160‰ to.219‰, with an altitudinal lapse rate（ALR） of.18‰ km~（-1）（R~2=0.83; p〈0.0001; n=29）. These δD_（wax） values appeared more enriched than those from the GG transect by ~40‰. We found that both the climate and moisture sources led to the differences observed in soil δD_（wax） values between the LM and GG transects. We found that, as a general rule, ε_（wax/rw）, ε_（wax/p） and εwax/sw values（i.e., the isotopic fractionation of δD_（wax） corresponding to δD_（rw）, δD_p and δD_（sw）） increased with increasing altitude along both the LM and GG transects（up to 34‰ and 50‰, respectively）. Basing its research on a comparative study of δD_（wax）, δD_p, δD_（rw）（δD_（springw）） and δD_（sw）, this paper discusses the effects of moisture recycling, glacier-fed meltwater, relative humidity（RH）, evapotranspiration（ET）, vegetation cover, latitude,topography and/or other factors on ε_（wax/p） values. Clearly, if ε_（wax-p） values at higher altitudes are calculated using smaller ε_（wax-p） values from lower altitudes, the calculated paleowaterδD_p values are going to be more depleted than the actual δD values, and any paleoaltitude would therefore be overestimated.

A total of 12 indices of temperature extremes and 11 indices of precipitation extremes at 111 stations in southwestern China at altitudes of 285-4700 m were examined for the period 1961-2008. Significant correlations of temperature extremes and elevation included the trends of diurnal temperature range, frost days, ice days, cold night frequency and cold day frequency. Regional trends of growing season length, warm night frequency, coldest night and warmest night displayed a statistically significant positive correlation with altitude. These characteristics indicated the obvious warming with altitude. For precipitation extreme indices, only the trends of consecutive dry days, consecutive wet days, wet day precipitation and the number of heavy precipitation days had significant correlations with increasing altitude owing to the complex influence of atmospheric circulation. It also indicated the increased precipitation mainly at higher altitude areas, whereas the increase of extreme precipitation events mainly at lowers altitude. In addition, the clearly local influences are also crucial on climate extremes. The analysis revealed an enhanced sensitivity of climate extremes to elevation in southwestern China in the context of recent warming.

The correlation between mean surface air temperature and altitude is analyzed in this paper based on the annual and monthly mean surface air temperature data from 106 weather stations over the period 1961-2003 across the Qinghai-Tibet Plateau. The results show that temperature variations not only depend on altitude but also latitude, and there is a gradual decrease in temperature with the increasing altitude and latitude. The overall trend for the vertical temperature lapse rate for the whole plateau is approximately linear. Three methods, namely multivariate composite analysis, simple correlation and traditional stepwise regression, were applied to analyze these three correlations. The results assessed with the first method are well matched to those with the latter two methods. The apparent mean annual near-surface lapse rate is -4.8 ℃ /km and the latitudinal effect is -0.87 ℃ /°latitude. In summer, the altitude influences the temperature variations more significantly with a July lapse rate of -4.3℃/km and the effect of latitude is only -0.28℃ /°latitude. In winter, the reverse happens. The temperature decrease is mainly due to the increase in latitude. The mean January lapse rate is -5.0℃/km, while the effect of latitude is -1.51℃ /°latitude. Comparative analysis for pairs of adjacent stations shows that at a small spatial scale the difference in altitude is the dominant factor affecting differences in mean annual near-surface air temperature, aided to some extent bydifferences of latitude. In contrast, the lapse rate in a small area is greater than the overall mean value for the Qinghai-Tibet Plateau （5 to 13℃ /km）. An increasing trend has been detected for the surface lapse rate with increases in altitude. The temperature difference has obvious seasonal variations, and the trends for the southern group of stations （south of 33 o latitude） and for the more northerly group are opposite, mainly because of the differences in seasonal variation at low altitudes. For yearly changes, the temperature for high-altitude stations occurs earlier clearly. Temperature datasets at high altitude stations are well-correlated, and those in Nanjing were lagged for 1 year but less for contemporaneous correlations. The slope of linear trendline of temperature change for available years is clearly related to altitude, and the amplitude of temperature variation is enlarged by high altitude. The change effect in near-surface lapse rate at the varying altitude is approximately 1.0℃ /km on the rate of warming over a hundred-year period.