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In the last few decades, the Loess Plateau had experienced an extensive vegetation restoration to reduce soil erosion and to improve the degraded ecosystems. However, the dynamics of ecosystem carbon stocks with vegetation restoration in this region are poorly understood. This study examined the changes of carbon stocks in mineral soil(0–100 cm), plant biomass and the ecosystem(plant and soil) following vegetation restoration with different models and ages. Our results indicated that cultivated land returned to native vegetation(natural restoration) or artificial forest increased ecosystem carbon sequestration. Tree plantation sequestered more carbon than natural vegetation succession over decades scale due to the rapid increase in biomass carbon pool. Restoration ages had different effects on the dynamics of biomass and soil carbon stocks. Biomass carbon stocks increased with vegetation restoration age, while the dynamics of soil carbon stocks were affected by sampling depth. Ecosystem carbon stocks consistently increased after tree plantation regardless of the soil depth; but an initial decrease and then increase trend was observed in natural restoration chronosequences with the soil sampling depth of 0–100 cm. Moreover, there was a time lag of about 15–30 years between biomass production and soil carbon sequestration in 0–100 cm, which indicated a long-term effect of vegetation restoration on deeper soil carbon sequestration. 相似文献
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茭白(Zizania latifolia)是我国南方重要的水生蔬菜,温度对其田间生产具有较大的影响。以浙江省主栽双季茭白品种浙茭911为对照,采用双向电泳技术(two-dimensional electrophoresis,2-DE)对茭白耐冷栽培品种龙茭2号叶片的差异表达蛋白进行比较鉴定分析,获得蛋白点数分布在822~955,差异蛋白点筛选表明,低温及恢复处理中,龙茭2号差异表达蛋白上调数量均高于浙茭911,差异表达蛋白下调数量均低于浙茭911;质谱成功鉴定了6个耐冷相关差异表达蛋白:IAA(indole acetic acid)生长素水解酶(IAA auxin amido hydrolase,IAA-AH)、甲酸四氢叶酸连接酶(putative formate-tetra-hydrofolate ligase,FSH)、苹果酸脱氢酶malate dehydrogenase,MDH)、6-磷酸甘露糖还原酶(mannose-6-phosphate reductase,M6PR)、ATP合成酶(ATP synthase CF1 alpha chain,ATPase)和分子伴侣cpn60-1(chaperonin cpn60-1,cpn60-1),分别与植物激素代谢、核酸合成、能量代谢、光合作用及蛋白折叠等功能相关。IAA-AH、MDH和分子伴侣cpn60-1在两个茭白品种中均表现出低温处理后表达量上调,恢复处理后表达量下调,其他3个蛋白在两个品种间表达变化存在差异;5℃低温处理时,龙茭2号中差异蛋白表达较为稳定,并能较好地恢复至对照水平。基于茭白转录组测序信息查询,克隆获得6个差异蛋白点相关基因的编码区序列并进行了荧光定量PCR验证分析。本研究从蛋白和分子水平阐明了双季茭白龙茭2号耐冷相关的部分蛋白及其表达变化,有助于揭示龙茭2号孕茭特性及其耐冷机制,为田间选育不同采收期的茭白耐冷新品种提供理论依据。 相似文献
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食用菌通常指可供人类食用的大型高等真菌,通称蘑菇,在我国自古被称为“山珍”。近年来,食用菌以其品种多样、口味独特、营养丰富且极具保健价值的特点越来越受到消费者的欢迎,联合国粮农组织倡导日常饮食做到“一荤一素一菌”,以更好地平衡健康膳食。我国当前正处在发展循环农业、高效农业的重要阶段,食用菌产业因其显著的社会、经济和生态效益,正越来越受到政府部门的青睐,也是农户投资小、周期短、见效快的好项目。笔者调查了湖南、黑龙江两省消费者对食用菌产品的需求情况,旨在为食用菌产业发展提供依据。 相似文献
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Zhang SY Jouanguy E Ugolini S Smahi A Elain G Romero P Segal D Sancho-Shimizu V Lorenzo L Puel A Picard C Chapgier A Plancoulaine S Titeux M Cognet C von Bernuth H Ku CL Casrouge A Zhang XX Barreiro L Leonard J Hamilton C Lebon P Héron B Vallée L Quintana-Murci L Hovnanian A Rozenberg F Vivier E Geissmann F Tardieu M Abel L Casanova JL 《Science (New York, N.Y.)》2007,317(5844):1522-1527
Some Toll and Toll-like receptors (TLRs) provide immunity to experimental infections in animal models, but their contribution to host defense in natural ecosystems is unknown. We report a dominant-negative TLR3 allele in otherwise healthy children with herpes simplex virus 1 (HSV-1) encephalitis. TLR3 is expressed in the central nervous system (CNS), where it is required to control HSV-1, which spreads from the epithelium to the CNS via cranial nerves. TLR3 is also expressed in epithelial and dendritic cells, which apparently use TLR3-independent pathways to prevent further dissemination of HSV-1 and to provide resistance to other pathogens in TLR3-deficient patients. Human TLR3 appears to be redundant in host defense to most microbes but is vital for natural immunity to HSV-1 in the CNS, which suggests that neurotropic viruses have contributed to the evolutionary maintenance of TLR3. 相似文献
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浓香型白酒的生产是以窖池为基础,窖池窖泥中栖息着庞大的微生物群系,微生物间相互作用形成浓香型白酒的独特风味,尤其以芽胞杆菌为主。本研究从泸州老窖酒厂300年窖池窖泥中分离出23株好氧芽胞杆菌属(Bacilli),经光学显微镜和菌落形态观察,23株好氧芽胞杆菌形态差异不显著。通过16S rDNA基因扩增,NCBI基因比对,构建系统发育树,结果表明,23株好氧芽胞杆菌主要为苏云金芽胞杆菌(Bacillus thuringiensis,Bt)、蜡样芽胞杆菌(B.cereus,Bc)和炭疽芽胞杆菌(B.anthrax),菌种间亲缘关系存在差异;窖泥中分离出的23株好氧芽胞杆菌亲缘关系近,遗传多样性较低。本研结果为了解白酒发酵过程中老窖泥周围环境的变化、提高白酒品质提供基础资料。 相似文献
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Saisai Hou Ruifang Zhang Chi Zhang Lei Wang Hong Wang Xin-Xin Wang 《Soil Use and Management》2023,39(4):1600-1617
Bupleurum falcatum L. has gained attention due to its medicinal value in its root. B. falcatum was continuously cultivated and intensively chemically fertilized in order to attain a high yield, which reduced the soil quality and caused continuous cropping problems. Thus, there is a significant impact on S. baicalensis yield and quality. To solve this problem, soil with 0 or 3 continuous cropping years (0- and 3-year soil) was fertilized with several organic materials, which are Bacillus subtilis, Bacillus mucilaginosus, humic acid fertilizer, biochar, and vermicompost. The experiment examined the effectiveness of B. falcatum's growth and nutrient uptake under various organic materials. It was shown that organic materials improved soil fertility and promoted the growth and nutrient uptake of B. falcatum. The combination of vermicompost and biochar had a better improvement effect. It increased soil nutrients by 23.8%–73.3% (0-year soil) and 24.6%–71.1% (3-year soil), respectively. In two types of soil, both microbial number and enzyme activity substantially increased. The B. falcatum shoot and root biomass with vermicompost was increased 74.8%–84.5% (without biochar) and 41.8%–71.1% (with biochar) in two types of soil. Vermicompost and biochar also significantly promoted the root development of B. falcatum. The root length increased by 13.3%–66.7%, the root diameter by 38.6%–84.8%, the root volume by 8.4%–61.3%, and the specific root length varied by −171.9% to 3.1% when compared with the control. The nutrient (N, P, and K) concentrations in shoots and roots changed from −3.9% to 67.2% and from 1.4% to 53.5%. All the findings demonstrated that long-term continuous cropping caused cropping obstacles, deteriorated soil quality, and inhibited the B. falcatum growth. Applying organic fertilizers, such as vermicompost and biochar, can help to improve soil quality, increase soil nutrients, promote the growth and nutrient absorption of B. falcatum, and eliminate continuous cropping obstacles. 相似文献
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以0.1 mmol L-1 SNP为NO供体,对小麦幼苗根系进行-0.5 MPa PEG胁迫处理,研究了NO对胁迫后叶片电子传递、光能分配和反应中心开放等PSII功能的影响,以探讨NO在干旱条件下对植物光合作用的调节作用。在干旱胁迫的第1天和第3天,SNP处理不但增加了水势(Ψw)和叶绿素含量,且能维持PSII反应中心的电子传递(ФPSII和Fm/Fo)及潜在高光合效率(Fv/Fo);干旱胁迫减少了PSII反应中心开放的比例(qP)和PSII反应中心捕获光能的转化效率,但SNP处理后PSII开放反应中心的比例增加,利于干旱条件下叶片吸收的能量用于光化学反应(Pr)和PSII反应中心安全地耗散过剩光能。综上所述,干旱条件下NO对小麦幼苗叶片的PSII功能具有调节作用。 相似文献
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添喂赖氨酸对小尾寒羊×无角陶赛特杂羔消化代谢和生长性能的影响 总被引：1，自引：0，他引：1
选取16只30日龄平均体重为（6.13±0.65）kg的小尾寒羊与无角陶赛特杂交F1代公羔,根据体重分为4组,在30-75日龄、76-120日龄和121-240日龄分别喂以日粮1、日粮2和日粮3,以研究添喂不同水平赖氨酸对羔羊采食量、体增重、消化率和屠宰性能的影响。结果表明,最佳添喂量（30-75日龄、76-120日龄和121-240日龄期间分别为1.2,0.8和0.4 g/kg日粮）时羔羊干物质自由采食量分别比对照增加14.10%（P〈0.01）,37.70%（P〈0.01）和30.29%（P〈0.01）,日增重分别比对照组提高52.70%（P〈0.01）,11.35%（P〈0.05）和34.94%（P〈0.01）,粗蛋白表观消化率分别比对照提高18.23%（P〈0.05）,11.06%（P〈0.05）和29.63%（P〈0.01）,氮保留率分别比对照提高17.13%（P〈0.01）,8.81%（P〈0.05）和22.37%（P〈0.01）,氮保留量分别比对照增加28.37%（P〈0.05）,40.37%（P〈0.05）和39.72%（P〈0.05）。30-240日龄平均日增重提高23.25%（P〈0.01）。最佳添喂量时240日龄羔羊的胴体重、胴体净肉重、瘦肉重和肥肉重分别比对照增加34.72%（P〈0.01）,37.41%（P〈0.01）,42.98%（P〈0.01）和21.96%（P〉0.05）。本试验表明,添喂未经处理的赖氨酸可显著促进240日龄以内羔羊的生长;30-75日龄、76-120日龄、121-240日龄3个阶段羔羊日粮赖氨酸的最适含量分别为2.2%,1.5%和0.7%。 相似文献
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北方冬麦区新育成优质小麦品种面条品质相关性状分析 总被引：5，自引：1，他引：4
为了解近年北方冬麦区育成优质小麦品种的品质状况,两年两点统一种植52份优质品种(系)及6份国外代表性品种,测定其磨粉品质、和面仪和混合实验仪特性、淀粉糊化特性及面条品质,并利用5个基因特异性标记分析基因型分布及其对品质性状的影响。结果表明,大部分品种为硬质、中强筋类型,品种间出粉率、面粉a*值、b*值、黄色素含量、PPO活性、和面仪参数、混合实验仪形成时间和稳定时间差异较大。和面仪8 min带宽和混合实验仪稳定时间可作为预测面条品质的重要指标,可分别解释面条总分变异33.3%和34.4%。Ppo-A1a和Ppo-A1b频率为41.4%和58.6%,两种基因型间PPO活性差异显著(P<0.05);Ppo-D1a和Ppo-D1b频率为51.7%和48.3%,但PPO活性差异不显著;Psy-A1a和Psy-A1b频率为81.0%和19.0%,两种基因型间黄色素含量差异显著(P<0.05);1BL/1RS易位和非易位品种频率为13.8%和86.2%,两种基因型间面粉L*值、黄色素含量、和面仪衰落势与8 min带宽、混合实验仪稳定时间等差异显著(P<0.05)。面条品质较好的品种包括Sunzell、石优17、郑麦366、中麦 895、周麦 26、CA1004和石4185。本研究明确了58份小麦品种(系)的品质特征和基因型分布,为优质小麦新品种选育和推广提供了重要信息。 相似文献