基于面向对象分类技术的沈阳市土地利用动态变化研究

基于RS和GIS技术,采用面向对象分类技术,根据沈阳市的实际情况,建立土地利用类型解译标志,利用多尺度分割方法进行影像分割,然后利用决策树法和最近邻的分类方法,建立分类规则,提取区域土地利用信息,得到该区域的两期土地利用/土地覆被数据,并对研究区的土地利用动态变化及引起这种变化的驱动力进行分析.研究中所采用的面向对象的分类方法在地表景观信息提取中充分利用了地物的光谱信息、纹理特征等特征,最大程度上克服由于不同地物光谱信息相似、相同地物光谱信息不同而造成的混分现象.     

河北丰宁招兵沟铁磷矿床地质及综合利用前景

河北丰宁招兵沟铁磷矿床为赋存于太古宇绿岩带内低品位特大型矿床。含磷岩系具近似绿岩带下部火山岩群的特点。铁磷矿体呈层状,大的透镜状产出,还伴生Ti、V 等有益元素。矿石选矿回收性能良好。通过对该区当前内生低品位铁磷矿开采情况的调查,认为我国北方低品位铁磷矿综合利用前景乐观。     

河流入海物质通量对海、陆环境变化的响应

入海河流物质通量研究是陆—海相互作用和全球海洋通量联合研究计划的重要命题。我国是最早开展物质通量研究的国家之一。自20世纪90年代以来,国家自然科学基金项目和国家重大基础研究计划项目都开展了有关河流和边缘海物质通量的研究,即将开始的全国海岸带环境调查专项也把主要河流物质入海通量及其海洋环境效应研究作为主要内容之一。根据当前国内外河流物质通量研究的最新进展,较系统地阐述了河流入海物质通量的概念和对邻近大陆和海洋环境变化的响应。并在此基础上强调指出,河流入海物质通量是研究陆—海相互作用及其全球变化效应的重要参量。归纳了河流入海物质通量研究中需要解决的关键问题。     

Tracing dissolved organic matter cycling in the eastern boundary of the temperate North Atlantic using absorption and fluorescence spectroscopy

Apparent oxygen utilization (AOU), dissolved organic carbon (DOC), coloured dissolved organic matter (CDOM) absorption spectra, and CDOM fluorescence characteristic of aromatic amino acids (excitation/emission 280 nm/320 nm; F(280/320)) and marine-humic like substances (320 nm/410 nm; F(320/410)) were measured in full depth during a cruise in the temperate Eastern North Atlantic (ENA). An optimum multi-parameter (OMP) inverse method was run to calculate water mass proportion-weighted average (archetypal) concentrations of these chemical parameters for all water masses and samples. Archetypal concentrations retain the variability due to water mass mixing and basin scale mineralization from the water mass formation sites to the study area. Conversely, the difference between measured and archetypal concentrations, retain the variability due to dissimilarities in mineralization processes within the study area. Our analysis indicates that DOC supported 26±3% of the AOU in the dark temperate ENA and that basin scale processes occurring at and from the formation area of the water masses explained 63% of the total DOC variability. Our data also suggests that DOC remineralized at the basin scale was of lower molecular weight, and with a lower proportion of fluorescent aromatic amino acids than found within the study area. The relationship between the absorption coefficient at 254 nm (a_CDOM(254)) and AOU indicates that a_CDOM(254) was consumed during organic matter remineralization in the dark ocean, with 55% of the variability being explained by basin scale processes. The relationships of F(320/410) with AOU and DOC confirmed that marine humic-like substances are produced by microbial degradation processes, at a rate of 6.1±0.9×10⁻³ mg equivalents of QS mol AOU⁻¹. Our results also indicate that basin-scale remineralization processes account for 85% of the total variability of F(320/410), emphasizing that large scale processes control the formation of humic-like substance in the dark ENA.     

杭州湾枯季水沙若干特征分析

根据2014年1月及2017年2月杭州湾大、小潮水沙资料,计算了流速、含沙量、单宽潮量、单宽输沙量,进而分析了潮周期断面净潮量、净输沙量和区域冲淤分布。研究发现杭州湾涨、落潮平均流速比值整体较20世纪八九十年代增大,绝大部分区域大于1.0,涨潮流相对增强,澉浦南岸和金山北岸尤为显著。含沙量平面上分布澉浦、杭州湾南岸两个高值区(大潮大于3 kg/m³,小潮大于1.3 kg/m³)以及北岸湾口至乍浦之间的低值区(大潮小于2 kg/m³,小潮小于0.9 kg/m³),随潮汛变化显著,最大含沙量浓度通常滞后于急流时刻。各测站涨、落潮量和输沙量呈现“大涨大落”和“大进大出”的特征,造成杭州湾短时间尺度内的“大冲大淤”。大潮两涨两落金山与乍浦、乍浦与澉浦之间区域净输沙量可达几千万吨,净冲淤则在几百万吨。     

青藏高原四季划分方法探讨

利用中国气象局国家气象信息中心提供的青藏高原60个测站1961~2007年逐日气温资料,分析常用的四季划分方法在高原的适用性,指出各种四季划分方法的不足和局限,并根据四季持续时间的合理性、物候特征、海拔高度、气候（温度）分布特征等因素提出了针对不同的生产、生活目的而建立的新四季划分方法。探讨认为：（1）根据高原物候特征和气温相结合的方式得到的＂物候四季划分方法＂即＂4℃-12℃-10℃-1℃＂对高原农牧业尤为适合;（2）＂海拔季节划分方法＂对高原旅游和人们衣着尤为适合,海拔季节划分方法把高原分成二个区：海拔4000m以上四季划分方法为＂5℃-12℃-12℃-5℃＂,4000m以下四季划分方法为＂5℃-15℃-15℃-5℃;＂（3）＂生活季节划分方法＂对高原不同区域的生产生活尤为适合,生活季节划分方法将高原分为三个区：Ⅰ区四季划分方法为＂6℃-16℃-16℃-6℃＂,Ⅱ区四季划分方法为＂5℃-12℃-12℃-5℃＂,Ⅲ区四季划分方法＂7℃-7℃＂划分春冬和秋冬,不存在夏季。最后,综合以上各种方法的优缺点,初步定义＂高原普适季节划分方法＂即＂5℃-15℃-15℃-5℃＂为高原总体的四季划分方法,对高原整体的国民经济和政府活动、旅游、人们的衣着、生活生产、季节类产品的销售具有总体的指导意义。     

DISTRIBUTIONS OF TOTAL, INORGANIC AND ORGANIC PHOSPHORUS IN THE SEDIMENTS NEAR THE HUANGHE RIVER ESTUARY

For some hundred surface sediment samples from five cores taken in two cruises near the Huanghe River Estuary, total phosphorus (TP (.inorganic phosphorus (IP (and organic phosphorus (OP)were determined.On the average, 527×10-6, 455×10~6 and 72×10-6 were found for TP,IP and OP for the surface sediments taken in the two cruises. The distribution of OP and IP was controlled by the sample particle size: OP content increased with the decreasing of the sample particle size, while the maximal value of IP was found in the silt fraction due to the existence of apatite in our samples. Vertical distributions reflected well the channel change of the Huanghe River. Results from the multiple regressions between the three forms of phosphorus and the percentages of different particle size agreed well with the analytical data.     

江西罗塘石膏矿床地质特征

江西省贵溪市罗塘石膏矿赋存于晚白垩世地层中,是一个湖相沉积型矿床,已探明资源储量在3000万吨以上,属大型规模。本文主要介绍矿床地质特征、矿石质量及开发利用方向。     

Incorporation of a dynamic root distribution into CLM4.5: Evaluation of carbon and water fluxes over the Amazon

Roots are responsible for the uptake of water and nutrients by plants and have the plasticity to dynamically respond to different environmental conditions. However, most land surface models currently prescribe rooting profiles as a function only of vegetation type, with no consideration of the surroundings. In this study, a dynamic rooting scheme, which describes root growth as a compromise between water and nitrogen availability, was incorporated into CLM4.5 with carbon–nitrogen(CN) interactions(CLM4.5-CN) to investigate the effects of a dynamic root distribution on eco-hydrological modeling. Two paired numerical simulations were conducted for the Tapajos National Forest km83(BRSa3) site and the Amazon, one using CLM4.5-CN without the dynamic rooting scheme and the other including the proposed scheme. Simulations for the BRSa3 site showed that inclusion of the dynamic rooting scheme increased the amplitudes and peak values of diurnal gross primary production(GPP) and latent heat flux(LE) for the dry season, and improved the carbon(C) and water cycle modeling by reducing the RMSE of GPP by 0.4 g C m~(-2)d~(-1), net ecosystem exchange by 1.96 g C m~(-2)d~(-1), LE by 5.0 W m~(-2), and soil moisture by 0.03 m~3m~(-3), at the seasonal scale, compared with eddy flux measurements, while having little impact during the wet season. For the Amazon, regional analysis also revealed that vegetation responses(including GPP and LE) to seasonal drought and the severe drought of 2005 were better captured with the dynamic rooting scheme incorporated.