都市城乡过渡带基层空间的演变特征

城乡过渡带30～150 m尺度的空间,属变化明显的都市基层空间系统。为描述这一地带的空间演变规律,本文以郑州、杭州、北京的建设用地为例展开了多重分形分析。本文依托广义、典型f(a)-a(q)曲线所划分的3个空间演变子系统,以城乡过渡带院落组级—居委会级空间为研究尺度区间,对之进行了空间多重分形特征的量化分析。分析显示,城乡过渡带的空间演变属宏、中观空间影响下的适应性变化,市场驱动色彩显著。总体上,城乡过渡带基层空间的演变较为复杂,并常会在一定尺度内形成典型、广义的空间多重分形特征,及其相应的斑块密度（q值）分布区。且受多种发展进程等因素的影响,多种空间子系统的演变强度常会不同,其在各尺度上的空间复合也会呈动态变化,进而城乡过渡带空间演变的“情景性”较强。但都市城乡过渡带的基层空间却不存在依中小城市→传统性特大城市→现代化特大城市→超大城市的必然演替过程,其变化更多应与各都市在城市体系中的地位、城乡融合的具体情景密切相关。本文根据满足全局性、局域性指标的情况,把多重分形的典型特征分布区拓展到了更广域的特征过渡区及退化区,进而增强了对现实地理空间真实发展状态的非线性描述。     

强壮前沟藻生消过程中水色组分吸收特性

依据2011-07强壮前沟藻藻种培养实验期间的实测数据,分析了其生消过程中各水色组分的吸收特性。结果表明:在生消过程的始末阶段,以非色素颗粒物和有色可溶性有机物(CDOM)吸收为主,中间阶段,则以浮游植物吸收为主。浮游植物吸收光谱在440nm和675nm存在明显的特征峰;在整个生消周期内先上升后降低,直至消失;非色素颗粒物和CDOM吸收光谱随波长增加均呈指数衰减趋势,前者光谱幅高先增后减,但后者变化无明显规律。各水色组分与叶绿素质量浓度均存在一定的相关关系,无论在生长期或是消亡期,浮游植物、非色素颗粒物吸收系数与叶绿素质量浓度存在正相关关系;但CDOM吸收系数与叶绿素质量浓度在生长期存在正相关关系,而在消亡期变为负相关关系。这可作为改进赤潮水体叶绿素质量浓度遥感算法、有效判别赤潮以及识别赤潮优势藻种等的科学依据。     

Effects of an artificial oyster shell reef on macrobenthic communities in Rongcheng Bay,East China

An artificial oyster shell reef was deployed in Rongcheng Bay, East China. However, the effects of this reef on the surrounding macrobenthic communities were unknown. We compared sedimentary factors, macrobenthic biomass, abundance, and community composition and ecological indicators between the reef and non-reef areas over a one year period. The mean values for chlorophyll a （Chl a）, total organic matter （TOM）, total organic carbon （TOC）, and total nitrogen （TN） content in surface sediments in the reef area were slightly higher than those in the non-reef area. The Chl a levels differed significantly between the two areas, but the TOM, TOC, and TN were not significantly different. The abundance of crustaceans was significantly different between the two areas, but the abundance and biomass ofpolychaetes, echinoderms, mollusk did not differ significantly. The permutational multivariate analysis of variance （PERMANOVA） revealed that the macrobenthic community differed significantly through time and analysis of similarity multivariate analyses （ANOSIM） revealed that the macrobenthic community differed significantly in some months. The ecological indicators revealed that the environmental quality of the reef area was slightly better than that of the non-reef area. Overall, our results suggest that the artificial oyster shell reef may change the macrobenthic community and the quality of the environment. Despite the lack of an effect in the short term, long-term monitoring is still needed to evaluate the effects of artificial oyster shell reefs on macrobenthic communities.     

两类La Nia季节演变过程的海气耦合特征对比

利用1951—2010年逐月的HadISST海表温度资料、SODA次表层海温资料和NCEP/NCAR再分析资料等,对比分析了东太平洋(EP型)La Nia和中太平洋(CP型)La Nia的海气耦合特征在季节演变过程中的差异。EP La Nia海表温度异常中心在发展年夏季出现于南美沿岸,随后向西移动,盛期最大海表温度异常中心位于赤道东太平洋,而CP La Nia海温异常中心少动,基本维持在160°W附近,其强度更强,持续时间更长。受海温分布形态影响,热带大气对两类La Nia的响应非常不同,成熟期间CP型在中太平洋偏旱的强度和范围比EP型大,且略偏西。发展年夏、秋季,北半球位势高度响应较弱;冬季,负PNA位相易伴随两类La Nia出现,但异常活动中心的位置和强度不同,在北大西洋其大气响应几乎相反,这些差异会引起显著不同的区域气候异常。     

The distribution of chlorophyll a and its influencing factors in different regions of the Bering Sea

The distribution of chlorophyll a(Chl a) and its relationships with physical and chemical parameters in different regions of the Bering Sea were discussed in July 2010. The results showed the seawater column Chl a concentrations were 13.41–553.89 mg/m2 and the average value was 118.15 mg/m2 in the study areas. The horizontal distribution of Chl a varied remarkably from basin to shelf in the Bering Sea. The regional order of Chl a concentrations from low to high was basin, slope, outer shelf, inner shelf, and middle shelf. The vertical distribution of Chl a was grouped mainly from single-peak type in basin, slope, outer shelf, and middle shelf, where the deep Chl a maxima(DCM) layer was observed at 25–50 m, 30–35 m, 36–44 m, and 37–47 m, respectively. The vertical distribution of Chl a mainly had three basic patterns: standard single-peak type, surface maximum type, and bottom maximum type in the inner shelf. The analysis also showed that the transportation of ocean currents may control the distribution of Chl a, and the effects were not simple in the basin of the Bering Sea. There was a positive correlation between Chl a and temperature, but no significant correlation between Chl a and nutrients. The Bering Sea slope was an area deeply influenced by slope current. Silicate was the factor that controlled the distribution of Chl a within parts of the water in the slope. Light intensity was an important environmental factor in controlling seawater column Chl a in the shelf, where Chl a was limited by nitrate rather than phosphate within the upper water. Meanwhile, there was a positive relationship between Chl a and salinity. Algal blooms broke out at Sta. B6 of the southwestern St. Lawrence Island and Stas F6 and F11 in the middle of the Bering Strait.     

不同浓度苯并（a）芘对杂色鲍抗氧化酶活性的影响

为阐释不同浓度苯并（a）芘[B（a）P]对杂色鲍（Haliotis diversicolor）的毒性效应,以0.02、0.04和0.08 mg/dm^33个质量浓度的B（a）P对杂色鲍进行水体暴露胁迫,7d后检测肌肉、外套膜、鳃、性腺、肾和肝胰腺的超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、谷胱甘肽S-转移酶（GST）和谷胱甘肽过氧化物酶（GPx）活性及还原型谷胱甘肽（GSH）含量.结果显示：0.02 mg/dm^3的B（a）P暴露对杂色鲍抗氧化系统的影响不明显,而0.04、0.08 mg/dm^3的B（a）P则显著抑制了SOD、CAT和GPx酶活性以及GSH含量,同时对GST酶活性具有显著的诱导作用;实验还发现,不同组织抗氧化酶活性对B（a）P胁迫的敏感性响应存在较大差异,其中鳃、肾脏和肝胰腺的敏感性响应明显高于肌肉和外套膜.上述结果表明,苯并（a）芘暴露对杂色鲍抗氧化酶活性的影响具有明显的剂量-效应关系及组织差异性,杂色鲍的鳃、肾脏或者肝胰腺的抗氧化酶响应多环芳香烃胁迫的更敏感,可作为B（a）P污染的生物标志物.     

基于经验模型的Hyperion数据植被叶绿素含量反演

对于反演植被叶绿素含量而言,基于Hyperion等高光谱传感器数据、利用经验方法建模是一种快速准确的方法。利用多种植被的实测数据以及Hyperion模拟数据,分析植被反射率及其变化形式与叶绿素含量的相关性,并进一步针对红边参数、植被指数等分析植被反射率与叶绿素含量的关系,选取最准确的经验建模方法。经过对比,改进的简单比值指数(modified simple ratio,MSR)与叶绿素含量相关性最高,其回归模型能比较准确地反演出叶绿素含量。通过Hyperion图像、利用MSR指数与实测叶绿素含量得到回归模型,建立区域叶绿素含量分布图;并对张掖地区植被叶绿素含量进行了反演,反演结果具有较高精度,相对误差低于5%。     

浅议赤潮

海洋是一种生物与环境、生物与生物之间相互依存，相互制约的复杂生态系统。系统中的物质循环、能量流动都是相对稳定，动态平衡的。当赤潮发生时这种平衡遭到干扰和破坏。在植物性赤潮发生初期，由于植物的光合作用。水体会出现高叶绿素a、高溶解氧、高化学耗氧量。赤潮造成的环境改变，使一些海洋生物不能正常生长，导致一些生物逃避甚至死亡，破坏了原有的生态平衡。     

黄骅坳陷地区正断层位移模式

黄骅坳陷属新生代张性盆地。在第三纪的ＮＷ—ＳＥ向区域拉张作用下，本区形成大量走向ＮＥ—ＳＷ的正断层。通过对该区正断层位移分布的研究，划分出Ｃ、Ｅ、Ｄ、Ｍ和Ｚ型五种断层位移模式，并进一步探讨了诸如断裂生长机制、岩石力学性质、相邻断层的相互作用、次级断裂的相互衔接这样几种控制因素对断层位移分布的影响。