青海湖布哈河下游地区植物群落多样性研究

根据野外样方调查资料，对青海湖西部布哈河下游地区8种植物群落进行了研究。结果表明：群落的多样性随丰富度的降低而呈下降趋势，均匀度的变化受物种丰富度的影响不大，群落的物种多样性指数与丰富度指数和均匀度指数均表现出极显著的正相关性（P〈0．01），相关系数分别为0．912和0．684；群落的均匀度与丰富度相关性不显著，说明物种多样性主要为物种丰富度所推动。

海北高寒草甸生态系统定位站辐射气候特征

以2000—03到2001—02的辐射观测资料，分析了海北高寒草甸生态系统定位站地区辐射及各分光辐射的变化特征．将为高寒草甸生态系统的物质循环、能量流动、草地生产力形成机制等问题的研究提供科学依据。结果表明：海北站区Eg、Er、UV、PAR、NIR和En具有明显的日、年变化，年内其总量分别达6278．867MJ／m^2、1515．139MJ／m^2、311．242MJ／m^2、2576．777MJ／m^2、3397．404MJ／m^2和2542．950MJ／m^2，其中在植物生长期的5—9月分别为3181．215MJ／m^2、698．021MJ／m^2、165．955MJ／m^2、1133．965MJ／m^2、1673．871MJ／m^2和1668．805MJ／m^2。年内Er、UV、PAR、NIR和Eh占Eg的比例分别为0．242、0．048、0．410、0．540和0．410，在植物生长期分别为0．219、0．052、0．413、0.528和0．527。对Eg和PAR提出了下列形式的模拟求算式．Eg=Eg0（0．089．7＋0．9768S／S0）和PAR=-3.8044＋0.4177％，模拟效果较好，可利用有关常规气象观测资料进行估算。

青海小叶杨物候变化及其对气候变化的响应

以青海省4个农气观测站的小叶杨物候期及气候资料，分析了小叶杨物候期变化及其对气候变化的响应。结果表明：小叶杨呈现出近10多年来树木绿叶期延长的趋势，但物候的早晚存在着明显的地域性差异；小叶杨物候对气温变化的反应比较敏感，上年9月至当年4月的平均气温升高1℃，小叶杨平均叶芽开放期提早5d，展叶普期提早4d，开花始期提早4d；上年9月至当年6月的平均气温升高1℃，平均种子成熟提早3d左右；上年9月至当年8月的平均气温升高1℃，平均叶全变色期约推迟4—5d，树木绿叶期延长12d；但小叶杨物候对降水的响应不明显，对日照时数变化的响应各地不一。

Effect of plateau zokors on vegetation characteristics and productivity of alpine meadow

This research was conducted on alpine meadow site at Menyuan county, Qinghai Province, People's Republic of China to determine the effects of native, subterranean rodent of Qinghai-Tibet grasslands, the plateau zokors (Myospalax baileyi), on seasonal above-and below-ground plant biomass, plant species diversity and productivity. Both total peaks of above-and below-ground biomass were the greatest (413.600 g/m~2 and 2297.502 g/m~2) in the patch no any plateau zokors colonized by plateau zokors over 10 years in August and October, respectively. Both above-and below-ground biomass were significantly increased in the patches where plateau zokors were removed or the burrow systems were abandoned for five years compared to the patches plateau zokors colonized over 10 years. However, both above-and below-ground biomass in abandoned patches were significantly lower than that in uncolonized patches. Monocotyledonous biomass was reduced greatly, but the non-palatable dicots were significantly increased in colonized patches. The palatable biomass of monocots and dicots were increased in abandoned patches. Total plant species diversity was the greatest in uncolonized patchesand least in abandoned patch. The total net primary production in colonized patches was reduced by 68.98% compared with uncolonized patches. Although the patches were without any plateau zokors disturbance for fives years, the total net primary production just reached 58.69% of the uncolonized patches. The above-ground net primary production in abandoned patches increased 28.74% and the below-ground increased 54.91% compared with the colonized patches. We suggest that plateau zokor-induced changes in plant above- and below-ground biomass and species diversity may lead to further alterations of nutrient cycling and trophic dynamics in this alpine meadow ecosystem.

Molecular systematics and biogeography of Crawfurdia, Metagentiana and Tripterospermum (Gentianaceae) based on nuclear ribosomal and plastid DNA sequences

Background and Aims The systematic position of the genus Metagentiana and its phylogenetic relationships with Crawfurdia, Gentiana and Tripterospermum have not been explicitly addressed. These four genera belong to one of two subtribes (Gentianinae) of Gentianeae. The aim of this paper is to examine the systematic position of Crawfurdia, Metagentiana and Tripterospermum and to clarify their phylogenetic affinities more clearly using ITS and trnL intron sequences.Methods Nucleotide sequences from the internal transcribed spacers (ITS) of nuclear ribosomal DNA and the plastid DNA trnL (UAA) intron were analysed phylogenetically. Ten of fourteen Metagentiana species were sampled, together with 40 species of other genera in the subtribe Gentianinae.Key Results The data support several previously published conclusions relating to the separation of Metagentiana from Gentiana and its closer relationships to Crawfurdia and Tripterospermum based on studies of gross morphology, floral anatomy, chromosomes, palynology, embryology and previous molecular data. The molecular clock hypothesis for the tested sequences in subtribe Gentianinae was not supported by the data (P < 0.05), so the clock-independent non-parametric rate smoothing method was used to estimate divergence time. This indicates that the separation of Crawfurdia, Metagentiana and Tripterospermum from Gentiana occurred about 11.4-21.4 Mya (million years ago), and the current species of these three genera diverged at times ranging from 0.4 to 6.2 Mya.Conclusions The molecular analyses revealed that Crawfurdia, Metagentiana and Tripterospermum do not merit status as three separate genera, because sampled species of Crawfurdia and Tripterospermum are embedded within Metagentiana. The speciation and rapid radiation of these three genera is likely to have occurred in western China as a result of upthrust of the Himalayas during the late Miocene and the Pleistocene.

东准噶尔和尔赛斑岩铜矿特征及其形成的构造背景

Hersai porphyry copper deposit(PCD) of eastern junggar, newly discovered copper deposit, is located at the eastern segment of the Xiemisitai-Kulankazigan-Zhifang-Qiongheba Paleozoic island arc, Eastern Junggar. The Hersai PCD is developed in a intrusive complex, characterized by intensive and multiform hydrothermal alteration, including potassic alteration, silification, chloritization，sericitization，kaolinitization and carbonatization. Granodiorite, grandiorite porphyry, granite and concealed explosion breccia are hosts of the ore bodies containing veinlet and disseminated ore. Ore-bearing granite (ZK107-1-9), granodiorite (ZK107-1-9) and Ore-barren granodiorite (HES2-1) are selected to date zircon U-Pb age by SHRIMP method, and have an age of 429.4±6.4Ma ,413.0±3.4Ma and 411.1±4.8Ma, respectively, showing that they were emplaced from Late Silurian to Early Devonian. In addition, sample ZK107-1-9 has some hydrothermal zircons with a weighted mean 206Pb/238U age of 404.9±3.7Ma which is interpreted to be related to the granodiorite porphyry. Re-Os dating of five molybdenite samples yielded a weighted average model age of 408.0±2.9Ma, indicating the metallogenic epoch of the Hersai PCD. The ore-forming age is close to the petrogenic time of garnodiorite (411-413Ma), this suggests the ore-forming porphyry is most possiblely granodiorite porphyry. Systematic major - trace elements and Rb-Sr-Sm-Nd-Pb-Hf isotopic characteristics were studied. Analysis results show that these intrusives have some interesting and special characteristics, as following:1) containing both calc-alkaline rocks and high potassium calc-alkaline rocks ; 2) have some characteristics of adakite, but not totally, such as much lower La/Yb ratios and no Eu anomaly or just faint Eu anomaly; 3) have an initial 87Sr/86Sr ratios(0.703852-0.704565) similar to that of BSE, positive εNd(t) values between 6.1 and 7.4, the initial 206Pb/204Pb values (17.576-17.912), 207Pb/204Pb values (15.400-15.453) , 208Pb/204Pb values (37.252-37.466) , and high εHf(t) values (10.2-15.4) close to the value of depleted mantle. These geochemical features suggest that these igneous rocks in the Hersai area not only have some characteristics of island arc, but also some characteristics that only appear in the continental margin arc. It is suggested that Hersai PCD is formed in the subduction setting by the partial melting of young crust. These works and advancements mentioned in the paper are helpful to understand the deposit geology, geochemistry and metallogenesis of Hersai PCD. It is also significant to understand mineralization and tectonic setting in the Qiongheba area.

淡水湖泊水体中溶解有机氮测定方法的对比

溶解有机氮（Dissolved Organic Nitrogen，DON）是天然水体中氮的重要组成部分，目前研究相对很少．本文对淡水中测定DON的两种常见方法即过硫酸钾湿氧化法（Persulfate Oxidation，PO）和高温催化氧化法（High Temperature Cataytic Oxidation，HTCO）进行了对比研究．结果表明：两种方法各有特点，湿氧化法相对较为理想．湿氧化法对不同氮标准化合物的回收率较高，平均为96．0±3．O％以上（杂环氮化合物除外）；对湖泊淡水样品，用PO法测定溶解有机氮的相对标准偏差范围为6．2％-12．5％．高温催化氧化法对不同氮标准化合物的回收率较低，平均为68．4±13．6％，需作进一步条件优化.

贵州滥木厂汞矿区土壤与大气间气态汞交换通量及影响因素研究

利用动力学通量箱-大气自动测汞仪联用技术，分别于2002年12月和2003年5月对贵州省西南部滥木厂汞矿区5个采样点的土壤汞释放通量进行了系统的测定。结果表明该区土壤是大气的重要汞释放源。5个采样点土壤释汞通量最高值达10543．7ng／(m^2·h)，平均值最高达(2283．3±2434．2)ng／(m^2·h)(n=152)。结果显示土壤总汞含量与土壤释汞通量关系密切，是决定土壤汞释放的内在因素，光照、温度、湿度和大气汞含量等环境因素与土壤释汞通量有较好的相关性，对土壤汞的释放有显著的影响.

川中丘陵区典型土地利用方式下磷素迁移的初步研究

通过野外定位观测,对川中丘陵区坡耕地、水田与林地地表径流水中磷素迁移形态、迁移通量进行了初步研究。结果表明,坡耕地、林地磷素迁移以颗粒吸附态为主,水田磷素迁移以水溶性磷为主,所有土地利用类型径流中总磷含量已超过水体富营养化的标准。坡耕地、水田和林地地表径流水中磷迁移的通量分别为0. 88 kg/(hm2 ·a) ,0. 15 kg/ (hm2 ·a) 与0. 33 kg/ (hm2 ·a) 。

初论特提斯构造域一些大型-超大型金属矿床集中区聚矿构造

特提斯构造域是目前世界关注和研究的地学前沿科学问题之一。I．Metcalfe从构造演化角度将其划分为古特提斯、中特提斯及新特提斯，代表了从古生代特斯洋三次打开与闭合的构造过程。从聚矿构造类型看，一些大型-超大型金属矿床不但与其构造域中的大陆边缘的张裂-伸展变形过程有密切关系。而且与其打开的同时，澳大利亚陆块内前泥盆纪大洋盆地的闭合及造山运动有关。

云南和老挝锡及铝土矿表生成矿作用对比研究

表生作用主要与气候、植被、基岩、地貌、时间等因素有关，具有与内生作用不同的特征，如低温、低压、水、二氧化碳、生物有机体等参与。目前发现的表生成矿的矿床类型有风化矿床和部分沉积矿床。表生作用形成多种矿床，包括（1）红土型的金、镍、铁、锰、钴、铝土、稀土元素、铀矿、砂锡、砂金、铌钽砂矿、金红石等残积坡积和淋积矿床；（2）高岭土矿、蒙脱土矿等残余富集矿床；（3）镍、铀矿等淋积矿床。此外还有一些沉积矿床。

安徽月山岩体岩石地球化学特征及成因

月山矿田是长江中、下游地区典型的夕卡岩-热液脉型铁、铜、金多金属矿田。月山岩体与金属矿床成因密切相关。通过对月山岩体系统的岩石学、岩石化学和微量元素地球化学特征研究，认为月山岩体是在区域拉张环境下，由亏损地幔低程度部分熔融形成的硅酸不饱和高钾碱性玄武岩浆经AFC机制形成的。

表生水条件下毒砂溶解作用动力学实验研究

毒砂氧化溶解和释放的砷将对周围水体造成污染。本文用混合流流动反应器研究了毒砂在温度为15、15、35和45℃的FeCl3酸性地表水作用下的氧化溶解过程。结果显示：在温度为15～35℃内，毒砂的氧化随FeCl3溶液浓度增加和反应温度升高而加速，而45℃时毒砂的反应速率反应降低；毒砂在与氧化剂FeCl3酸性溶液（浓度小于1×10^-4mol·kg^-1）反应时释放到溶液中的砷为As(Ⅲ），As(Ⅲ）在FeCl3酸性溶液中很快被氧化成As(V）。