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Effects of diatoms on reproduction and growth of marine copepods

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Progress in Natural science:Materials International 2004年第10期14卷 1-7页

作者： ZHANG Guangtao 1,2 and SUN Song 1 (1.Key Laboratory of Marine Ecology&Environment sciences,Institute of Oceanology,Chinese academy of sciences,Qingdao266071,China 2.Graduate School,Chinese academy of sciences,Beijing100039,China) Lab. of Marine Ecology Inst. of Oceanology Chinese Acad. of Sci. Qingdao 266071 China Graduate Sch. Chinese Acad. of Sci. Beijing 100039 China

Two hot spots in marine ecology,deleterious effects of diatoms and feeding selectivity of copepods,as well as new progress on these two issues achieved in the recent ten years,are *** two issues are considered correlated *** and their metabolites can induce deleterious effects on growth,reproduction and development of copepods,including increase of mortality and decrease of egg production,hatching and growth *** negative effects,resulting from either chemical toxin or nutritional defi-ciency,can be conquered in natural environments by diverse *** is therefore concluded that deleterious effects of diatoms observed in laboratory or during blooming period are only a special case that accommodation of feeding strategy of copepods is *** under-stand their feeding strategy in natural environments is a prerequisite to explaining the mechanisms of deleterious effects caused by diatoms,and makes it possible to re-evaluate the energy flow in marine ecosystems.

关键词： diatoms copepod feeding strategy reproduction deleterious effects

Spatial integration of oasis city group around the western margins of the Tarim Basin

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Journal of Arid Land 2010年第3期2卷 214-221页

作者： Yang, Yu Zhang, XiaoLei Lei, Jun Dong, Wen Zeng, WeiYao Gao, Chao Chinese acad sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China Chinese acad sci Grad Univ Beijing 100049 Peoples R China

In this paper,the oasis cities in Kashgar Prefecture and Kizilsu Kirgiz Autonomous Prefecture are taken as an example,through the factor analysis,spatial attraction interaction model and location quotient methods,urban hierarchy system,the intensity of urban economic ties,economic subordination degree,and structure of city functions were analyzed. The results indicated:(1) The urban hierarchy system takes Kashgar city as the main center,Artux city,Yarkant county and Maralbexi county as the sub-centers; (2) The intensity of economic ties among Kashgar city and each county is much higher than others. The interaction of Kashgar city,Shufu county and Shule county are the strongest,and the economic ties of Yarkant,Kagilik,Poskam counties are relatively close; All cities in the study area are economically subordinate to Kashgar city. (3) Three cities of Kashgar city,Shufu county and Shule county should connect strongly,with Kashgar city as the core. The cities and towns along the Southern Xinjiang Railway and along National Road 315 should be regarded as two strips,and the two city strips along the border,and the city strip along Provincial Road 215 should be treated as three axes. The ring structure strategy of 'core ring,closer ring and radiated ring' was proposed. (4) It was proposed to build Kashgar city group in the north,and Yarkant city group in the south,Maralbexi city group in the southeast,and Taxkorgan border city group with four inner groups’ development strategy.

关键词： Tarim Basin oasis city city group spatial integration

A very strong summer monsoon event during 30-40 kaBP in the Qinghai-Xizang (Tibet) Plateau and its relation to precessional cycle

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Chinese science Bulletin 1999年第20期44卷 1851-1858页

作者： Shi, YF Liu, XD Li, BY Yao, TD Chinese acad sci Lanzhou Inst Glaciol & Geocryol Lanzhou 730000 Peoples R China Chinese acad sci Lanzhou Inst Plateau Atmospher Phys Lanzhou 730000 Peoples R China Chinese acad sci Inst Geog Beijing 100101 Peoples R China

Guliya ice core records, high lake-level records in the Qinghai-Xizang Plateau and at its north side as well as vegetation succession records indicated that during the period of 30-40 kaBP, namely the later age of the megainterstadial of last glacial period, or the marine oxygen isotope stage 3, the climate of the Qinghai-Xizang Plateau was exceptionally warm and humid, the temperature was 2-4℃ higher than today and the precipitation was 40% to over 100%

关键词： Qinghai-Xizang (Tibet) Plateau very strong summer monsoon precessional cycle 30-40 kaBP.

Fatigue Crack Propagation Behavior of TiNi_(50.6)Shape Memory Alloy

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Journal of Materials science & Technology 2001年第4期17卷 403-408页

作者： Guangbin RAO, Jianqiu WANG, We KE and Enhou HAN The State Key Laboratory of Corrosion and Protection, Institute of M-tal Research, Chinese academy of sciences,Shenyang 110016, China Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

The fatigue crack propagation behavior of TiNi50.6 shape memory alloy was studied. The ex- periment results showed that the crack propagation properties of this alloy display difference and similarity in comparison with common metallic materials. Because of the stress concentra- tion there was stress induced martensite transformation (SIMT) near the crack tip though the nominal stress was lower than the threshold stress of SIMT. The position and the amount of SIMT was in situ observed by a quester remote measurement system (QRMS). The observation results showed that the position of SIMT was beside the crack tip and was not in the plastic zone of common metallic materials (in front of the crack tip). The SIMT zone at an angle of about 45°to the direction of the crack propagation, like a butterfly,appeared in the loading process, disappeared in the unloading process and grew larger with the increase of K. The crack propagation rate(da/dN) followed the linear law in lg-lg plot. Observation of the crack surface showed fatigue striation clearly. The relationship between the site and the size of the plastic zone and the SIMT zone is discussed and a model is given to explain both the similarity and the difference of the crack propagation property of TiNi50.6 to common metal materials.

关键词： Fatigue Crack Propagation Behavior of TiNi Shape Memory Alloy

An analysis of oasis stability in arid areas:a case study in the northern slope areas of the Tianshan Mountains

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Journal of Arid Land 2009年第1期1卷 49-56页

作者： Luo, GePing Lu, Lei Yin, ChangYing Feng, YiXing Chinese acad sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China Chinese acad sci Grad Sch Beijing 100049 Peoples R China

This paper discusses oasis stability at regional scale with a case study in the northern slope areas of the Tianshan Mountains (NSTM). The results showed certain significant aspects. (1) As long as water resources in the oasis keep stable and their utilization efficiency can be maintained or gradually increased, the primary productivity could be continuously increased and the natural primary productivity keeped relatively stable. In this case, it is considered that the oasis is stable and its sustainable development can be achieved at regional scale. (2) Considering the availability of water resources in the oases, the oases on the alluvial-diluvial fans are highly stable. In the alluvial plain downstream of the groundwater overflowing zones the oases are moderately stable and in the lacustrine deltas or dry lacustrine deltas the oases are lowly stable. (3) Enlargement of oases and the increase of water resources and vegetation coverage in the oasis will certainly enhance the 'cold-island effect' of the oasis and increase the stability of oases.

关键词： oasis stability regional scale geographical location 'cold-island effect' the northern slope areas of the Tianshan Mountains

Plant diversity-productivity patterns in the alpine steppe environment of the Central Tianshan Mountains

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Journal of Arid Land 2009年第1期1卷 43-48页

作者： Hu, YuKun Li, KaiHui Gong, YanMing Yin, Wei Chinese acad sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China Chinese acad sci Grad Univ Beijing 100039 Peoples R China

The biodiversity-productivity relationship is an important topic in the research of biodiversity and ecosystem function. The plant diversity productivity pattern is commonly unimodal and positively correlated. This paper researches the characteristics of plant diversity-productivity patterns in the Bayanbuluk alpine steppe in the central Tianshan Mountains, Xinjiang, China, and analyzes the effects of environmental factors on the distribution of plant communities, species composition, plant diversity and productivity in the steppe. The results show a positive correlation between plant diversity and productivity. DCCA (detrended canonical correspondence analysis) ordination reveals a significant relationship between the effects of air temperature, soil moisture content, available soil nitrogen, relative humidity and pH value on the distribution and composition of plant communities. There are significant correlations between the soil moisture content, relative humidity, pH value, air temperature and species richness and the aboveground biomass of Gramineae and Cyperaceae, and also significant correlations between the relative humidity, pH values and the total aboveground biomass of plant communities.

关键词： Tianshan Mountains plant diversity productivity DCCA ordination alpine steppe environmental factor

Processes and trends of the land use change in Aksu watershed in the central Asia from 1960 to 2008

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Journal of Arid Land 2010年第3期2卷 157-166页

作者： Zhou, DeCheng Luo, GePing Lu, Lei Chinese acad sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China Chinese acad sci Grad Univ Beijing 100049 Peoples R China

Land use change (LUC) in trans-boundary watersheds is of great importance to environmental assessment. The Aksu River is the largest trans-boundary river crossing Kyrgyzstan and China,but there was little information on the LUC of the watershed. We quantitatively investigated the processes and trends of its LUC by using analytic models based on the land use data derived from the remote sensing images and topographic maps. The LUC was in the quasi-balanced status with a slight difference between the loss and the gain of the area for most land use types during the period of 1960-1990,whereas transferred to the unbalanced status with significant difference between the loss and gain of the area during the period of 1990-2008. At the same time,land conversion direction changed from two-way transition to one-way transition for the most land use types. The integrated rate of net change of land use during the period of 1990-2008 is 2.1 times of that during the period of 1960-1990. Information on the processes and trends of LUC is valuable for better understanding the environmental changes across the whole trans-boundary watershed,and helpful to decision-making management for Kyrgyzstan and China.

关键词： land use change (LUC) trans-boundary river Aksu River remote sensing

Retinal bipolar cells——A model for the study of neuronal signal integration

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Chinese science Bulletin 1999年第19期44卷 1737-1743页

作者： Jiulin Du Xiongli Yang Chinese acad sci Shanghai Inst Physiol Shanghai 200031 Peoples R China Chinese acad sci Key Lab Neurobiol Shanghai 200031 Peoples R China

Being the functional basis of neural networks, neuronal signal integration has been currently becoming a hot point of neuroscience research. Active and passive membrane properties of retinal bipolar cells, temporal and spatial distribution of synaptic inputs to these cells are described, and modulation of signal integration characteristics of these cells under different reti-

关键词： retinal bipolar cells neuronal signal integration passive membrane properties active membrane properties graded potential.

Effects of Carbonate on Exchangeability and Bioavailability of Exogenous Neodymium in Soil

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Journal of Rare Earths 2001年第3期19卷 233-237页

作者：徐仲均李德成杨剑虹彭安 Res. Cent. for Eco-Environ. sci. Chinese Acad. of Sci. Beijing 100085 China

The effects of carbonate on the exchangeability and the bioavailability of exogenous neodymium in soil were studied by Nd-147 isotopic tracer method. Exchangeable Nd was extracted by I mol(.)L(-1) NaAc (pH8.2) in the experiment. The results indicate that whether carbonate exists in soil or not, beyond 99% of exogenous Nd is adsorbed by soil. Low-concentration carbonate (0.8 similar to 1.6 g(.)kg(-1)) can reduce exchangeable Nd concentration in soil, while high-concentration carbonate (4.0 g(.)kg(-1)) impacts little on the exchangeable Nd concentration. In addition, carbonate of 0.8 similar to 1.6 g(.)kg(-1) in soil can inhibit wheat seedlings to absorb Nd. However, when the carbonate concentration rises to 4.0 g(.)kg(-1) the inhibition will become indistinct.

关键词： rare earths carbonate neodymium exchangeability bioavailability