论“盐湖农业”

盐湖的生态系统包括盐水域和环糊盐沼带两个亚系统。当代以盐湖盐藻，卤虫，螺旋藻和盐生植物的研究，开发利用及菌紫膜机制的发现为代表，标志着在人类长期经营淡水－海洋生物与低盐耕地之后，一个崭新的盐水域与盐沼研究开发领域－“盐湖农业”的到来，它即是一种盐水域水产养殖业，又与盐水域周缘盐生生物群密切关连，构成水产－农牧业研究开发“的交织”的领域，它是人类索聚蛋白质，食物色素等食物和多种工业。

盐湖中的生物资源

在地球表面的陆地区域,分布有无数的湖泊,面积大小不等,水体深浅不一。盐湖是湖泊中的一种重要类型。它是一种含盐量较高的咸化水体。在盐湖中,不仅存在石盐、碱类、芒硝等普通无机盐矿产及钾、锂、镁、硼、溴、硝石、石膏和医用淤泥等化工、农业、轻工、冶金、建筑和医药等重要原料,而且赋存具有氯化钙、钨、铯、铷、铀、锶、水菱镁矿、沸石、锂蒙脱石及天然气等。

保护“地球之肾”挑战与机遇并存

进入21世纪以来,人类越来越深切地感受到地球生态恶化带来的一系列严重后果,湿地的重要性也被越来越多人所熟悉。湿地与森林、海洋并称为全球三大生态系统。根据世界《湿地公约》的定义,湿地包括了所有陆地淡水生态系统(如河流、湖泊、沼泽)以及陆地和海洋过渡地带的滨海湿地生态系统,同时还包括了海洋边缘部分的咸水、半咸水水域。虽然全球湿地面积仅占陆地面积的6%,但湿地生态系统支持了全部淡水生物群落和部分盐生生物群落,具有极其特殊的生态功能,是地球上最重要的生命支持系统。人们将湿地称为"地球之肾"。

Soil Inorganic Nitrogen and Microbial Biomass Carbon and Nitrogen Under Pine Plantations in Zhanggutai Sandy Soil

The dynamics of soil inorganic nitrogen （NH4^＋ -N and NO3^- -N） and microbial biomass carbon （Cmic） and nitrogen （Nmic） under 30-year-old fenced Pinus sylvestris L. var. mongolica Litvin （SF）, unfenced P. sylvestris L. var. mongolica Litvin （SUF）, and unfenced Pinus densiflora Siebold et Zucc. （DUF） plantations in the Zhanggutai sandy soil of China were studied during Apr. to Oct. 2004 by the in situ closed-top core incubation method. All mentioned C and N indices in each stand type fluctuated over time. The ranges of inorganic N, Cmic, and Nmic contents in the three stand types were 0.7-2.6, 40.0-128.9, and 5.4-15.2 μg g^-1, respectively. The average contents of soil NH4^＋ -N and Cmic under the three 30-year-old pine plantations were not different. However, soil NO3^ -N and total inorganic N contents decreased in the order of SUF ≥ SF ≥ DUF, the Nmic content was in the order of SF = SUF 〉 DUF, and the Cmic：Nmic ratio was in the order of SUF = DUF 〉 SF. Seasonal variations were observed in soil inorganic N, microbial biomass, and plant growth. These seasonal variations had certain correlations with microbe and plant N use in the soil, and their competition for NH4^＋ -N was mostly regulated by soil N availability. The influence of tree species on inorganic N and Nmic were mainly because of differences in litter quality. Lack of gazing decreased the Cmic：Nmic ratio owing to decreased carbon output and increased the ability of soil to supply N. The soil N supply under the P. sylvestris var. mongolica plantation was lower than under the P. densiflora plantation.

The Occurrence of an Exotic Bisexual Artemia Species, Artemia franciscana, in Two Coastal Salterns of Shandong Province, China

The alien halophilous Artemia species, Artemia franciscana, was found in Chengkou Saltern and Yangkou Saltern of Shandong Province, P.R. China. Although the indigenous parthenogenetic Artemia is detectable, the exotic species is dominant in both salterns. The cross-breeding tests between the exotic A. franciscana and 5 bisexual Artemia species were conducted. The results of hybridization and morphological observations on the exotic A. franciscana are briefly presented in this short communication.

Improving zinc recovery by thermoacidophilic archaeon Acidianus copahuensis using tetrathionate

The attachment and bioleaching experiments were conducted to evaluate the zinc recovery from Hualilan ore by thethermoacidophilic archaeon Acidianus copahuensis. Cells of this species pregrown on tetrathionate showed higher capability ofattachment to the ore than cells pregrown on other energy sources and such attachment seemed to be mediated by the product ofextracellular polymeric substances. A. copahuensis achieved a successful bioleaching of the ore reaching 100% of zinc recoverywhen tetrathionate was added. Simultaneous addition of yeast extract and tetrathionate maintained the zinc extraction at higher rate.Zinc dissolution kinetics was controlled by chemical reaction in cultures with the external addition of tetrathionate but by thediffusion through a product layer of jarosite in the other cultures.

Toxicity and Accumulation of Selenite in Four Microalgae

The toxicity and bioaccumulation of selenite in four microalgae, Spirulina platensis, Dunaliella salina, Dunaliella bardawill and Phaeodactylum tricornutum cultured in the presence of selenite were investigated. Lower concentrations of selenite were generally nontoxic and frequently stimulated algal growth, while higher concentrations of selenite inhibited algal growth. Selenite was more toxic to D. salina and D. bardawill than to S. platensis and P. tricornutum . All algae cultured in selenite were able to incorporate Se to different degrees, which depended on algal species. The distributions of selenite among intracellular macromolecular compounds were different among algal species: most of the selenite was associated with proteins in S. platensis, D. salina and D. bardawill , while most of the selenite was associated with lipids in P. tricornutum , which reflected the physiological differences among the algae. These observations suggest that algae are able to accumulate selenite and bind it with intracellular macromolecular compounds when exposed to high concentration of selenite. This may represent a form of storage or detoxification of selenite by the algae.

Composition and Origin of Ferromanganese Crusts from Equatorial Western Pacific Seamounts

In the equatorial western Pacific, iron-manganese oxyhydroxide crusts(Fe-Mn crusts) and nodules form on basaltic seamounts and on the top of drowned carbonate platform guyots that have been swept free of pelagic sediments. To date, the Fe-Mn crusts have been considered to be almost exclusively of abiotic origin. However, it has recently been suggested that these crusts may be a result of biomineralization. Although the Fe-Mn crust textures in the equatorial western Pacific are similar to those constructed by bacteria and algae, and biomarkers also document the existence of bacteria and algae dispersed within the Fe-Mn crusts, the precipitation, accumulation and distribution of elements, such as Fe, Mn, Ni and Co in Fe-Mn crusts are not controlled by microbial activity. Bacteria and algae are only physically incorporated into the crusts when dead plankton settle on the ocean floor and are trapped on the crust surface. Geochemical evidence suggests a hydrogenous origin of Fe-Mn crusts in the equatorial western Pacific, thus verifying a process for Fe-Mn crusts that involves the precipitation of colloidal phases from seawater followed by extensive scavenging of dissolved trace metals into the mineral phase during crust formation.

Isolation and characterization of a novel strain of Natrinema containing a bop gene

A novel member of extremely halophilic archaea, strain AJ2, was isolated from Ayakekum Lake located in Altun Mountain National Nature Reserve of Xinjiang Uygur Autonomous Region in China. The strain A J2 requires at least 10% (w/v)NaCl and grows 10% to 30% (optimum at 20%). Phylogenetic analysis based on 16S rDNA sequence comparison revealed that strain A J2 clustered to three Natrinema species with less than 97.7% sequence similarities, suggesting A J2 is a novel member of Natrinema. A bacteriorhodopsin-encoding (bop) gene was subsequently detected in the A J2 genome using the polymerase chain reaction technique. The cloning and sequencing of a 401 base pairs fragment indicated the deduced amino acid sequence of bop from A J2 is different from that reported for bacteriorhodopsins. This is the first reported detection of a bop gene in Natrinema.

Salinity Tolerance and Genetic Diversity of the Dinoflagellate Oxyrrhis marina

To evaluate the relationship between salinity tolerance and genetic diversity of plankton,we collected a wild species of plankton from Taipingjiao,Qingdao.The fragment of ITS1-5.8S rDNA-ITS2 was extracted and sequenced.The results showed that the plankton belongs to Oxyrrhis marina.The salinity tolerance of O.marina ranges from 4 to 60.Seven selected groups were built up to evaluate salinity tolerance and to assess genetic diversity by RAPD.The salinity tolerance comparison revealed considerable differences among groups:the strains of O.marina in group 4 could survive under salinity from 4 to 32,while the strains selected for salinity 60 died under the salinity lower than 16.Analysis of genetic diversity of the seven groups showed that the mean genetic diversity index value was 0.28,but it was only 0.16 in selected group of 4 and was 0.24 for group 60.The result of AMOVA suggested a significantly positive relationship between the salinity tolerance and genetic diversity of O.marina (P<0.01).This study indicates that consideration of intraspecific genetic divergence in O.marina might be indispensable when using it as a model in the study of salinity tolerance of wild plankton.

Lake-margin ecosystems of saline lakes of the Borzya group(Zabaikalsky Krai, Russia) during the initial filling phase

This article presents the results of hydrochemical and hydrobiological studies of shallow saline lakes of the Borzya group(Zabaikalsky Krai, Russia) at the initial filling phase. The lake-margin ecosystems of the studied lakes are characterized by varying degrees of salinity from polyhaline to brine water. Cyclical variations of meteorological conditions and high salinity determined that the compositions of the aquatic organisms are specific, mostly between stenohaline and euryhaline species, the quantities are low, and the community structures are simple.

Performance and Modeling of an Up-flow Anaerobic Sludge Blanket(UASB) Reactor for Treating High Salinity Wastewater from Heavy Oil Production

In this study,an up-flow anaerobic sludge blanket(UASB) reactor was applied to treat the high salinity wastewater from heavy oil production process.At a HRT of ≥24 h,the COD removal reached as high as 65.08% at an influent COD ranging from 350mg/L to 640mg/L.An average of 74.33% oil reduction was also achieved in the UASB reactor at an initial oil concentration between 112mg/L and 205mg/L.These results indicated that this heavy oil production related wastewater could be degraded efficiently in the UASB reactor.Granular sludge was formed in this reactor.In addition,two models,built on the back propagation neural network(BPNN) theory and linear regression techniques were developed for the simulation of the UASB system performance in the oily wastewater biodegradation.The average error of COD and oil removal was-0.65% and 0.84%,respectively.The results indicated that the models built on the BPNN theory were wellfitted to the detected data,and were able to simulate and predict the removal of COD and oil by the UASB reactor.

“绿桥”衔架“新楼兰”——天山北坡实施“绿桥系统”南坡实施“新楼兰工程”

如何保护新疆平原绿洲地区，并形成的新的畜牧产业带，以避免其陷入荒漠化的绝境?目前，在中国科学院学部重大科学咨询项目报告《西部生态环境建设与可持续发展》中．

广东湿地忧思录

被忽略的"宝库"提起"湿地"这个名词,很多人说不出个所以然。然而,如果告诉你,在我省分布众多的海岸滩涂、湖泊、河流、库塘等等就是湿地,曾经牵动万千生灵的海啸和赤潮也跟湿地有关时,你会发现湿地其实就在我们身边,我们赖之生存,与之息息相关。国际上通常把森林、海洋和湿地并称为全球三大生态系统。显然,作为地球上最重要的生命支持系统,湿地却并不像另外两者那样得到人们足够的认识和重视,更勿论保护意识了。可以说,长久以来,被誉为"地球之肾"、"城市之肺"的湿地,却被人们忽略甚至人为破坏了。湿地生态系统支持了全部淡水生物群落和部分盐生生物群落。

Effects of Epigeic Earthworms on Decomposition of Wheat Straw and Nutrient Cycling in Agricultural Soils in a Reclaimed Salinity Area:A Microcosm Study

Earthworms, one of the most important macroinvertebrates in terrestrial ecosystems of temperate zones, exert important influ- ences on soil functions. A laboratory microcosm study was conducted to evaluate the influence of the earthworm Eisenia fetida on wheat straw decomposition and nutrient cycling in an agricultural soil in a reclaimed salinity area of the North China Plain. Each microcosm was simulated by thoroughly mixing wheat straw into the soil and incubated for 120 d with earthworms added at 3 different densities as treatments： control with no earthworms, regular density （RD） with two earthworms, and increased density （ID） with six earthworms. The results showed that there was no depletion of carbon and nitrogen pools in the presence of the earthworms. Basal soil respiration rates and metabolic quotient increased with the increase in earthworm density during the initial and middle part of the incubation period. In contrast, concentrations of microbial biomass carbon and microbial biomass quotient decreased in the presence of earthworms. Earthworm activity stimulated the transfer of microbial biomass carbon to dissolved organic carbon and could lead to a smaller, but more metabolically active microbial biomass. Concentrations of inorganic nitrogen and NO^-N increased significantly with the increase in earthworm density at the end of the incubation （P ~ 0.05）, resulting in a large pool of inorganic nitrogen available for plant uptake. Cumulative net nitrogen mineralization rates were three times higher in the ID treatment than the RD treatment.

Formation and influencing factors of carbonate source rock of the Lower Permian Chihsia Formation in Chaohu region, Anhui Province

Highly-mature carbonate source rock is essential to the exploration of oil and gas in southern China. In this study, the carbonate strata in the relatively well-developed Lower Permian Chihsia Formation (located in Chaohu, Lower Yangtze) were targeted, and the formation and influencing factors of source rock were discussed based on paleoenvironment reconstruction using comprehensive sedimentology, palynofacies, and organic geochemistry data. The results demonstrate that the Chihsia Formation is oxygen-deficient biogenic carbonate sediments, with marked variations in the organic and inorganic components, formed during a period of Permian transgression. The formation of source rock is the combined result of high bioproductivity and oxygen-deficient environment generated by transgression and oxygenation events which frequently occurred during transgression periods. Source rock was affected by self-dilution effects and diagenesis, causing its heterogeneous distribution in many intervals. Source rock is over 40 m thick, and can be identified based on its different organic, biological, and mineral composition characteristics. The carbonate rock appears to require no specific clay content in order to become a source rock. The combination of sedimentology, palynofacies, and organic geochemistry has provided an effective means for evaluating and predicting high-maturity carbonate source rock in the region.

The response of soil respiration to different N compounds addition in a saline-alkaline grassland of northern China

The increase in atmospheric nitrogen(N)deposition has profound effects on soil respiration(SR).However,the responses of SR to the addition of different N compounds,particularly in saline-alkaline grasslands remain unclear.A 3-year controlled field experiment was conducted to investigate the responses of SR to different N compounds(NH,NO,(NH),SO,and NH,HCO,)during the growing seasons in a saline-alkaline grassland located in the agro-pastoral ecotone of northern China.Our results demonstrated that SR showed a bimodal pattern and a significant interannual diference that was regulated by air or soil temperature and precipitation.Nitrogen addition had a significant effect on SR,and the effect of N addition on SR varied yearly,which was related to seasonal precipitation.The mean SR across 3 years(2017-2019)was increased by 19.9%,13.0%and 16.6%with the addition of NH,NO,(NH,),SO,and NH,HCO3,respectively.The highest effect of NH,NO3 addition on SR across 3 years was ascribed to the highest aboveground net primary production,belowground net primary production(BNPP)and soil NO,-concentrations.SR(C loss)was significantly increased while plant productivity(C input)did not significantly change under NH,HCO,addition,indicating a decrease in C sequestration.In addition,BNPP was the main direct factor influencing SR in this saline-alkaline grassland,and soil salinization(e.g.soil base cations and pH)indirectly affected SR through soil microorganisms.Notably,NH,NO,addition overestimated the response of SR to N addition,and different N compounds should be considered,especially in saline-alkaline grassland.

Bio-Fertilizer,Ground Magnesium Limestone and Basalt Applications May Improve Chemical Properties of Malaysian Acid Sulfate Soils and Rice Growth

Acid sulfate soils are normally not suitable for crop production unless they are appropriately ameliorated. An experiment was conducted in a glasshouse to enhance the growth of rice, variety MR219, planted on an acid sulfate soil using various soil amendments.The soil was collected from Semerak, Kelantan, Malaysia. Ground magnesium limestone(GML), bio-fertilizer, and basalt(each 4t ha-1) were added either alone or in combinations into the soil in pots 15 d before transplanting. Nitrogen, P and potash were applied at 150, 30, and 60 kg ha-1, respectively. Three seven-day-old rice seedlings were transplanted into each pot. The soil had a p H of 3.8 and contained organic C of 21 g kg-1, N of 1.2 g kg-1, available P of 192 mg kg-1, exchangeable K of 0.05 cmol c kg-1,and exchangeable Al of 4.30 cmol c kg-1, with low amounts of exchangeable Ca and Mg(0.60 and 0.70 cmol c kg-1). Bio-fertilizer treatment in combination with GML resulted in the highest p H of 5.4. The presence of high Al or Fe concentrations in the control soil without amendment severely affected the growth of rice. At 60 d of growth, higher plant heights, tiller numbers and leaf chlorophyll contents were obtained when the bio-fertilizer was applied individually or in combination with GML compared to the control. The presence of beneficial bacteria in bio-fertilizer might produce phytohormones and organic acids that could enhance plant growth and subsequently increase nutrient uptake by rice. Hence, it can be concluded that addition of bio-fertilizer and GML improved rice growth by increasing soil p H which consequently eliminated Al and/or Fe toxicity prevalent in the acid sulfate soil.

Exopolysaccharide-Producing Plant Growth-Promoting Rhizobacteria Under Salinity Condition

Salt-tolerant plant growth-promoting rhizobacteria （PGPR） can play an important role in alleviating soil salinity stress during plant growth and bacterial exopolysaccharide （EPS） can also help to mitigate salinity stress by reducing the content of Na＋ available for plant uptake. In this study, native bacterial strains of wheat rhizosphere in soils of Varanasi, India, were screened to identify the EPS-producing salt-tolerant rhizobacteria with plant growth-promoting traits. The various rhizobacteria strains were isolated and identified using 16S rDNA sequencing. The plant growth-promoting effect of inoculation of seedlings with these bacterial strains was evaluated under soil salinity conditions in a pot experiment. Eleven bacterial strains which initially showed tolerance up to 80 g L-1 NaC1 also exhibited an EPS-producing potential. The results suggested that the isolated bacterial strains demonstrated some of the plant growth-promoting traits such as phosphate solubilizing ability and production of auxin, proline, reducing sugars, and total soluble sugars. Furthermore, the inoculated wheat plants had an increased biomass compared to the unoinoculated plants.

Effects of Rice-Wheat Rotation and Afforestation on Microbial Biomass Carbon in Coastal Salt-Affected Soils of Eastern China

Rice-wheat rotation and poplar afforestation are two typical land use types in the coastal reclaimed flatlands of eastern China. This study investigated two rice-wheat rotation lands （one reclaimed from 1995 to 2004 and cultivated since 2005, RW1, and the other reclaimed from 1975 to 1995 and cultivated since 1996, RW2） and a poplar woodland （reclaimed from 1995 to 2004 and planted in 2004, PWl） to determine the effects of land use types and years of cultivation on soil microbial biomass and mineralizable carbon （C） in this coastal salt-affected region. The results showed that the soil in PWl remained highly salinized, whereas desalinization was observed in RWl. The total organic C （TOC） in the top soil of PWl and RW1 did not show significant differences, whereas at a soil depth of 20-30 cm, the TOC of RWl was approximately 40%-67% higher than that of PWl. The TOC of 0-30-cm soil in RW2 was approximately 37% higher than that in RW1. Microbial biomass C （MBC） and mineralizable C （MNC） exhibited the trend of RW2 〉 RWl 〉 PWl. Sufficient nutrition with more abundant C substrates resulted in higher MBC and MNC, and soil respiration rates were negatively correlated with C/N in RWl and RW2. Nutrient deficiency and high salinity played key roles in limiting MBC in PWl. These suggested that rice-wheat rotation was more beneficial than poplar afforestation for C accumulation and microbial biomass growth in the coastal salt-affected soils.