南亚热带常绿阔叶林优势种群的生物量与生物量增量

粘木种群的生物量为７０．１４ｔ／ｈｍ２，生物量增量为２．３２ｔｈｍ２ａ－１。其总生物量的９０％以上分布在ｄ≥２０ｃｍ的大树，仅有０．０４％～０．０５％分布在ｄ＜１０ｃｍ的小树。在各器官的分配是：树干为６５％，根为２５％，枝为１１％，而叶仅占有２％。粘木的平均径向增长为０．３５ｃｍ／ａ。应用树干解析法和形率法估算树干的生物量，两者的结果差别不大。但形率法则既省力省时，又较方便。粘木的形率为０．７１。

不同遮阴处理对大花萱草形态及生物量的影响

[目的]研究不同遮阴条件对大花萱草生长的影响。[方法]对3种不同大花萱草的品系进行遮阴处理,在生长季内对其形态及生物量进行观测。[结果]在40%光照条件下,3种大花萱草在形态上表现良好,观赏性较高;低于40%的透光率不利于其物质积累,生物增量减少,但根部增量总体大于叶片。[结论]大花萱草更适宜在40%以上的光照条件下作观赏地被。

土壤水分含量对银杏生长及生物量分配的影响

应用温室盆栽试验方法,采用完全随机试验设计,研究了1 年生银杏(Ginkgo biloba L.)实生苗在不同土壤水分条件下的生长和生物量分配。试验共设16 个处理,即4 个银杏半同胞家系(44 号、11 号、55 号、32号)、4种水分水平(土壤含水量为土壤田间持水量的80%,60%,40%和20%),处理时间为100 d。研究结果表明:(1)银杏4家系相对高生长、相对地径生长、生物量增量、单株叶面积、单株根系体积等均随着土壤水分含量的减少而减少;(2)55号和44号家系随着土壤水分含量的减少,根冠比逐渐增大,而32 号和11 号家系在前3种水分条件下随着土壤水分含量的减少,根冠比逐渐增大,但在W4 水分条件下,根冠比均减少;(3)随着土壤水分含量的减少,银杏4家系根、茎和叶生物量增量均减少,但不同的家系减少程度不同,4 个银杏家系在不同土壤水分条件下,根、茎和叶生物量增量均表现为根的最多,茎的次之,叶的最少;(4)不同家系银杏生物量增量分配到根系的比例随土壤水分含量的减少而增大,而分配到茎和叶中的比例则随着土壤水分含量的减少而减少。

河北省祥云湾人工鱼礁区网采浮游植物群落结构的时空变化特征及其与关键环境因子的关系

为探究河北省祥云湾人工鱼礁区浮游植物群落结构特征的时空变化规律,明确人工鱼礁区建设对浮游植物的养护效果及其与环境因子的关系,于2021年5月、8月、11月和2022年1月对祥云湾人工鱼礁区及对照区海域开展了网采浮游植物和关键环境因子季度调查。结果表明,4个季度共发现浮游植物3门39属70种,其中硅藻种类数最多(78.6%);浮游植物丰度呈现显著季节变化,夏、秋季丰度最高,2处人工鱼礁区浮游植物的年平均丰度为313.5×10^(4) cells/m^(3),是对照区浮游植物丰度的1.4倍;除春季外,人工鱼礁区浮游植物的丰富度指数、多样性指数和均匀度指数均高于对照区,且礁区春-夏和夏-秋季节礁区优势种更替率低于对照区,表明人工鱼礁区群落结构相比对照区更稳定;人工鱼礁区浮游植物主要类群的生物增量指数为0.9~3.6,特别是硅藻类群的生物增量指数平均达到1.8;Pearson相关性分析显示,浮游植物丰度主要受TP、TN、NH_(4)-N、NO_(3)-N和DIP的影响,且各季节之间存在显著差异。研究表明,人工鱼礁建设对浮游植物具有良好的养护效果,且养护效果主要与营养盐的时空变化密切相关。

Effects of NaCl stress on seed germination, leaf gas exchange and seedling growth of Pteroceltis tatarinowii

Effects of NaCI on seed germination, leaf gas exchange and seedling growth were investigated. The germination of P. tatarinowii seeds was delayed in the presence of NaCl, and was significantly inhibited when NaCl concentration exceeded 17 mM （1.0 g·L^-1）. NaCl treatments induced reductions of transpiration rate, stomatal conductance and net photosynthetic rate and their reductions were significant with the increasing of NaCl concentration. However, intercellular CO2 concentration in seedling leaves under salt stress was significantly higher than that of controls. There was a significant reduction in survival, basal diameter increment and height increment witl increasing NaCl concentration 50 days after NaCl treatment, and a significant reduction in the dry weight increment of roots, stems, and leaves was also observed in the NaCl treatments. The deleterious effect on the biomass increment was more evident in the case of stems and leaves. Results from this study suggest that P. tatarinowii is sensitive to salinity stress and the salinity threshold for seedling growth might be less 34 mM （2.0 g· L^-1）.

Effects of benzo(a)pyrene exposure on the antioxidant enzyme activity of scallop Chlamys farreri

Scallop Chlamys farreri was exposed to different concentrations of benzo(a)pyrene (BaP) (0.5 μg/L, 1.0 μg/L, 10.0 μg/L and 50.0 μg/L) for 30 days in seawater. The 7-ethoxyresorufin O-deethylase (EROD) activity was significantly induced, and increased with the increasing BaP concentration. The glutathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), Glutathione peroxidase (GPx) activities increased in short time at low concentration of BaP, and was significantly depressed at high concentrations. Scallop gill was more sensitive to BaP than the digestive gland, and the digestive gland was the main tissue to deal with oxyradicals. The contents of malondialdehyde (MDA) increased with the exposure time and there was a positive correlation (concentration-effect) between the MDA content and the concentration of BaP. The biomarkers determined in this experiment had important roles in detoxification, and showed great potential as biomarkers for oxidative stress. Controlled laboratory experiments designed to simulate field exposure scenarios are particularly useful in ascertaining biomarkers suitable for use with complex contaminant mixtures in the marine environment.

Effects of simulated flue gases on growth and lipid production of Chlorella sorokiniana CS-01

To study the abilities of Chlorella sorokiniana CS-01 on using CO2 from flue gases to produce biodiesel,the microaglae was cultured with different simulated flue gases containing 5%-15%(volume fraction) of CO2.The results show that strain CS-01 could grow at 15% CO2 and grow well under CO2 contents ranging from 5%-10%.The maximal biomass productivity and lipid productivity were obtained when aerating with 10% of CO2.The lipids content ranged from 28% to 43% of dry mass of biomass.The main fatty acid compositions of strain CS-01 were C14-C18(>72%) short-chain FAMEs(known as biodiesel feedstocks).Meanwhile,the biodiesel productivity was over 60%,suggesting that Chlorella sorokiniana CS-01 has a great potential for CO2 mitigation and biodiesel production.Furthermore,differential expression of three genes related to CO2 fixation and fatty acid synthesis were studied to further describe the effect of simulated flue gases on the growth and lipid accumulation of strain CS-01 at molecular level.

What Life Is and How It Originated

This paper refutes the mechanistic interpretation of cellular dynamics and contends that the life-giving principle is sustained growth a biological system and is uninterrupted growth balanced in a dynamic state by synthesis and dissolution. The process began by an oxidation/reduction reaction on the surface of pyrite energized photovoltaically by sunlight. Hydrogen sulfide was oxidized, carbon dioxide was reduced, and phosphate on the surface of the pyrite was a reactant. The first organic compounds were sulfides and phosphoglycerates. These organophosphates were at the center of the energy cycle of all life where the dehydration of a relatively unreactive ＂low-energy＂ two-phosphoglycerate transforms it into the ＂high-energy＂ phosphoenolpyruvate. Life began as a growth process and continues to grow ceaselessly out of necessity. It cannot discontinue the life-giving energy flow without irreparable loss of the process. All forms of life past and present were and are stabilized systems in which the growth process is contained in metabolic turnover.

Comparative Assessment of the Effect of Wastewater Sludge Biochar on Growth,Yield and Metal Bioaccumulation of Cherry Tomato

To investigate the potential effects of wastewater sludge and sludge biochar on growth, yield and metal bioaccumulation of cherry tomato （Lycopersicon esculentum L.）, a pot experiment was carried out under greenhouse environment with three different treatments, control soil （CP）, soil with wastewater sludge （SS） and soil with sludge biochar （SB）, to reveal the comparative effect between the amendments of wastewater sludge and sludge biochar. The soil used for pot experiment was Chromosol. Wastewater sludge and sludge biochax produced through pyrolysis process at 550 ℃ were applied at 10 t ha-1. No significant difference was found in growth and production of cherry tomatoes between wastewater sludge and sludge biochar applications to the soil. The accumulation rates of metals in the fruits were lower in the treatment with sludge biochar than in the treatment with wastewater sludge. The study highlights the benefits of risk mitigation from toxic metal accumulation in fruits using wastewater sludge and sludge biochar as soil conditioners.

Synergistic Effects of Biochar and NPK Fertilizer on Soybean Yield in an Alkaline Soil

Biochar effects on legume growth and biological nitrogen fixation have been studied extensively, mostly in acidic soils with laboratory produced biochar. In the present study, a pot experiment in a full factorial experimental design was performed to examine soybean yield and nodulation of three genotypes grown with or without biochar and NPK fertilizers in an alkaline soil. We observed synergistic effects of biochar and NPK fertilizer applications on biomass and seed yields for all three soybean genotypes. Total biomass production and seed yield increased on average by 67% and 54%, respectively, with biochar and by 201% and 182% with NPK fertilizer application compared to the control. When applications of biochar and NPK fertilizer were combined, the increases were 391% and367%, respectively. However, the biomass production in the control was very low(692 kg ha-1) due to a high soil p H(8.80). The nodulation increased with biochar and NPK fertilizer applications, and was largest with the combined application. A correlation was found between leaf chlorophyll content(single photon avalanche diode value) and nodule number. We suggested that the synergistic increase in yield was due to a decrease in soil p H caused by biochar and NPK fertilizer applications thereby increasing P availability in this alkaline soil.

Response of Microbial Communities in Soil to Multi-level Warming in a Highland Barley System of the Lhasa River

No studies have examined the effect of experimental warming on the microbial biomass and community composition of soil in agricultural ecosystem on the Qinghai-Tibet Plateau. Thus it is unclear whether the influences of experimental warming on microbial communities in soil are related to warming magnitude in croplands on this Plateau. This study performed warming experiment(control, low-and high-level) in a highland barley system of the Lhasa River in May 2014 to examine the correlation between the response of microbial communities in soil to warming and warming magnitude. Topsoil samples(0–10 and 10–20 cm) were collected on September 14, 2014. Experimental warming at both low and high levels significantly increased soil temperature by 1.02 ℃ and 1.59 ℃, respectively at the depth of 15 cm. Phospho lipid fatty acid(PLFA) method was used to determine the microbial community in soil. The low-level experimental warming did not significantly affect the soil’s total PLFA, fungi, bacteria, arbuscular mycorrhizal fungi(AMF), actinomycetes, gram-positive bacteria(G+), gram-negative bacteria(G–), protozoa, the ratio of fungi to bacteria(F/B ratio), and ratio of G+ to G–(G+/G– ratio) at the 0–10 and 10–20 cm depth. The low-level experimental warming also did not significantly alter the composition of microbial community in soil at the 0–10 and 10–20 cm depth. The high-level experimental warming significantly increased total PLFA by 74.4%, fungi by 78.0%, bacteria by 74.0%, AMF by 66.9%, actinomycetes by 81.4%, G+ by 67.0% and G– by 74.4% at the 0–10 cm depth rather than at 10–20 cm depth. The high-level experimental warming significantly altered microbial community composition in soil at the 0–10 cm depth rather than at 10-20 cm depth. Our findings suggest that the response of microbial communities in soil to warming varied with warming magnitudes in the highland barley system of the Lhasa River.

Temporal Variations in Growth and Aboveground Biomass of Phragmites australis and EVI Analysis in Jiaozhou Bay Coastal Salt Marshes, China

To better ascertain leaf, stem and flower traits, and analyze aboveground allocation during the vegetation period, three sampling vegetation transects were settled and reed samples were collected at intervals to determine morphological parameters and dry and wet weights in Jiaozhou Bay wetland. Remote sensing data were also combined to evaluate regional biomass through EVI regression models. Results show that growth dynamics of leaves and stems changed during the vegetation period. Stem length increased rapidly and peaked in September（194.40 ± 23.89 cm）, whereas leaf width peaked in July. There was a significantly negative correlation between stem length and stem diameter with a value of-0.785. Stem biomass was higher than that of leaves, and the maximum value of aboveground biomass was 27.17 ± 3.56 g. F/C exhibited a tendency to increase and values ranged from 0.37–0.76. The aboveground biomass of sample plots reached a peak of 2356 ± 457 g/m^2 in September. EVI was 0.05–0.5; EVI and biomass had a better fitting effect using the power-exponent model compared with other models and its function was y = 4219.30 x^0.88（R^2 = 0.7810）. R^2 of the other three models ranked as linear function〉 polynomial function 〉exponent function, with the values being 0.7769, 0.7623 and 0.6963, respectively. EVI can be used to estimate vegetation biomass, and effectively solved the problems of the destructive effect to sample plots resulting from traditional harvest methods.

Biological reaction signal enhancement in porous silicon Bragg mirror based on quantum dots fluorescence

In this paper, we mainly study the preparation of an optical biosensor based on porous silicon(PSi) Bragg mirror and its feasibility for biological detection. The quantum dot(QD) labeled biotin was pipetted onto streptavidin functionalized PSi Bragg mirror samples, the affinity reaction between QD labeled biotin and streptavidin in PSi occurred, so the QDs were indirectly connected to the PSi. The fluorescence of QD enhanced the signal of biological reactions in PSi. The performance of the sensor is verified by detecting the fluorescence of the QD in PSi. Due to the fluorescence intensity of the QDs can be enhanced by PSi Bragg mirror, the sensitivity of the PSi optical biosensor will be improved.