水稻生产能力核算及其在生产管理分区中的应用——以浙江省富阳市为例

水稻生产能力是影响水稻生产增长和可持续发展的关键.在耕地质量分级的基础上,对浙江省富阳市水稻生产能力进行评价,并通过抽样调查分等单元的可实现生产力和依据水田质量的地力指数建立可实现产能的核算模型,对区域水稻的生产能力和可实现的增长潜力进行分析.结果表明:研究区水田地力指数与水稻产量的关系密切,水稻产量随着地力指数的升高而提高;单季水稻种植制度下,全市水稻可实现产能1.70× 105 t,是单季水稻实际产能(1.04×105 t)的1.6倍;2009年,单季水稻实际单产7676 kg·hm-2,可实现单产8831kg·hm-2,单产增长潜力为15％,表明该市水稻生产能力存在很大的提升潜力,通过对各乡镇水稻生产能力、生产规模的比较优势和可提升潜力的分析,将该市水稻生产划分为重点提升区、优化建设区和发展保护区.     

基于AnnAGNPS模型的三峡库区黑沟小流域退耕还林生态服务价值

利用三峡库区黑沟小流域退耕还林工程实施前后监测资料,并基于AnnAGNPS模型获取该流域径流、土壤侵蚀和养分流失等数据,客观计量流域10种情景(A～J)生态服务物质量,进而估算各情景生态服务价值量.结果表明:退耕还林实施的10种情景中,流域生态服务物质量均发生了变化.情景B之径流、泥沙、总氮、总磷和有机碳的年输出量最高,分别为455 mm、56.8 t·hm-2、132 kg·hm-2、33 kg·hm-2和678 kg·hm-2,而情景J中上述指标最低,分别为303 mm、4.8 t·hm-2、75 kg·hm-2、18 kg·hm-2和383 kg·hm-2,分别下降了33.4%、91.5%、43.1%、45.4%和43.5%;退耕还林工程不同阶段流域生态服务价值也发生了变化,情景B最低,为225万元,情景J最高,为291万元,增加了29.3%.利用实地监测和模型输出的方法进行流域生态服务价值量的计量较为客观,避免了一些生态效益计算上的盲目性,但该方法所需数据量庞大,过程繁杂,限制了其推广应用.     

羌塘高原寒草地生态系统生产力动态

基于实测气象数据和遥感数据,分析了藏北地区气候变化趋势,并采用植被-气候综合模型和CASA模型模拟分析了藏北草地潜在和现实净第一性生产力(NPP)的动态变化和空间格局.结果表明:1955-2004年间,羌塘高原年平均气温上升了1.37 ℃,降水量增加了63 mm,中、东部区域的气候趋于暖湿化,西部区域趋于暖干化,目前气候变化尚未引起草地退化.草地潜在NPP平均值为东部＞中部＞西部.1982-2004年,由于水热条件的变化,中部区域的潜在NPP增加值最高,达0.55 t·hm-2·a-1,东部和西部分别为0.51和0.21 t·hm-2·a-1;东、中、西部现实NPP增量分别为-0.19、-0.03和0.20 t·hm-2·a-1.超载过牧是东、中部草地退化的主要原因,中部是草地保护恢复工程的最佳实施区域.     

长白山高山冻原生态系统三种养分含量的空间分布

对长白山高山冻原生态系统中 3种养分 (N、P和 S)在植被 -凋落物 -土壤中的空间分布规律进行了研究。结果表明 :(1)在长白山高山冻原植被亚系统中 ,3种养分总含量分布规律是石质高山冻原 (ST) >典型高山冻原 (TT) >沼泽高山冻原 (WT) >草甸高山冻原 (MT) >石海高山冻原 (RT) ;3种养分积累总量为 72 .4 6 kg· hm- 2 ,其中 N、P和 S分别是 4 8.5 5 kg· hm- 2 ,10 .33kg· hm- 2 和 13.6 1kg· hm- 2 ;生物量与养分积累分布规律是 WT>TT>MT>ST>RT。 (2 )在长白山高山冻原凋落物亚系统中 ,平均凋落物量是 1.96 kg· hm- 2 ;3种养分积累总量为 :82 .5 kg· hm- 2 ,其中 N、P和 S分别是 4 6 .2 8kg· hm- 2 ,2 1.14 kg· hm- 2 和 15 .0 8kg· hm- 2 ;养分积累总量分布规律是 TT>WT>RT>MT>ST。 (3)长白山高山冻原土壤 (0～ 2 0cm)亚系统中 ,养分积累总量为 39.6 t· hm- 2 ,其中 N、P和 S分别是 2 3.76 t· hm- 2 ,5 .86 t· hm- 2和 9.98t· hm- 2。 4 )在长白山高山冻原生态系统中 ,3种养分总积累量为 4 0 6 4 4 .98kg· hm- 2 ,其中 N、P和 S分别是 2 4 734.85 kg· hm- 2 ,10 0 18.7kg·hm- 2 和 5 891.4 3kg· hm- 2 ,土壤库是长白山高山冻原的主要养分储存库     

中国有机肥料养分资源潜力和环境风险分析

基于<中国农业年鉴2006)和其他文献的基础数据,计算了2005年中国人畜禽排泄物和秸秆数量及其产生的养分量.结果表明,2005年中国人畜禽排泄物总量为46.25亿t,秸秆总产量为6.43亿t.中国有机肥料养分资源潜力巨大,2005年人畜禽排泄物和秸秆共产生N、P2O5、K2O养分量分别为2824.52、1282.93、2947.99万t,分别为化肥N、P2O5、K2O投入量的1.08、0.86和4.56倍.但不同区域差异较大,其中河南、山东和四川省人畜禽排泄物产生N、P2O5、K2O量最多,均>400万t,西北地区和北京、天津、上海等地人畜禽排泄物产生的养分总量较少.秸秆中N、P2O5、K2O含量在河南和山东2个粮食主产省最高,均>150万t;西北地区秸秆养分产生量相对较少.单位农田面积人畜禽排泄物的N、P2O5和K2O养分负荷量以北京最高,达到787.26 kg·hm-2,其次是天津和上海,分别为515.31和505.35 kg·hm-2,环境风险较大.     

天山中部巴音布鲁克高寒草原大气无机氮沉降

随着我国经济的不断发展,人为活动导致的大气氮沉降显著升高,并已影响到偏远地区的生态系统.为了系统评价天山中部巴音布鲁克高寒草原的大气氮沉降现状,2010年5月至2011年12月对研究区域的氮素干、湿沉降进行观测分析.结果表明:研究区气态HNO3、NH3和NO2的年沉降通量分别为1.47、0.68和0.13 kg N·hm-2,颗粒物中铵态氮(NH4+)和硝态氮(NO3-)的年通量分别为0.23、0.25 kg N·hm-2;降水中NH4+-N和NO3--N的年沉降通量分别为2.47和1.59 kg N·hm-2.巴音布鲁克高寒草原的大气氮沉降通量为6.82kg N·hm-2.其中,湿沉降为4.06 kg N·hm-2·a-1,干沉降为2.76 kg N·hm-2·a-1.研究区氮沉降具有明显的季节变化特征:干沉降主要集中在春、夏季,占干沉降总量的72.1%;湿沉降主要集中在夏、秋季,占湿沉降总量的78.3%.     

长白山北坡土壤氮矿化时空分异特征

利用土壤温度连续观测数据,基于文献报道的土壤氮矿化测定数据,对长白山主要林型的年矿化量进行模拟计算,同时修正了以往利用气温计算造成的偏差以及相关模型中的参数错误.根据长白山各植被带的土壤温度观测数据,对各植被带的矿化量进行估计.位于基带的针阔混交林的矿化量为58.5 kg · hm-2 · a-1,红松云冷杉林为34.5 kg · hm-2 · a-1,岳桦云冷杉林为28.5 kg · hm-2 · a-1,苔原为19.6 kg · hm-2 · a-1.建立了通用于各植被带的土壤矿化对温度(t)的综合回归模型(y=0 038255e(0.1392t)).同时用所建立的综合方程,模拟计算了各海拔高度土壤氮矿化季节变化,并指出海拔每升高100m矿化速率降低2.31 kg · hm-2 · a-1.     

种植密度和施氮水平对小麦吸收利用土壤氮素的影响

2011-2013小麦季,在大田条件下设置2个氮肥水平(180和240kgN· hm-2)和3个种植密度(135、270和405万·hm-2),并将15N-尿素分别标记在20、60和100 cm土层处,研究种植密度-施氮互作对小麦吸收、利用土壤氮素及硝态氮残留量的影响.结果表明:种植密度从135万·hm-2增加至405万·hm-2,小麦在20、60和100 cm土层的15N吸收量分别增加1.86、2.28和2.51 kg·hm-2,地上部氮素积累量和吸收效率分别提高12.6％和12.6％,氮素利用效率降低5.4％;施氮量由240 kg N·hm-2降至180 kg N·hm-2,小麦在20、60 cm土层的15N吸收量分别降低4.11和1.21 kg·hm-2,在100 cm土层的15N吸收量增加1.02 kg·hm-2,地上部氮素积累量平均降低13.5％,氮素吸收效率和利用效率分别提高9.4％和12.2％.施氮180kg N·hm-2+种植密度为405万·hm-2处理与施氮240 kg N·hm-2+种植密度为270或405万·hm-2处理相比,其籽粒产量无显著差异,深层土壤氮素的吸收量显著提高,氮素吸收效率和利用效率分别提高13.4％和11.9％,O～ 200 cm土层的硝态氮积累量及100～ 200 cm土层硝态氮分布比例降低.在适当降低氮肥用量条件下,通过增加种植密度可以促进小麦吸收深层土壤氮素,减少土壤氮素残留,并保持较高的产量水平.     

黄土高原南部旱作水分产量潜势计算模型及其参数修正

建立了旱作水分产量潜势计算模型 ,并对模型中的主要参数 (光能利用率、作物产量反应系数和作物系数等 )进行了修正 ,同时提出作物耗水量和水分订正系数等的估算方法 .冬小麦水分产量潜势为 530 0～ 630 0 kg· hm- 2 ,春玉米为 770 0～ 90 0 0 kg·hm- 2 .此外 ,本文还对农田水分条件进行了评价 ,指出黄土高原南部的东部地区水分条件较差 ,有较大的灌溉增产潜力 .     

杭州西湖风景名胜区园林废弃物生产生物能源潜力

在当前我国景区节能减排目标难以达到的情况下,发展生物能源将为此提供一个途径.本文以杭州西湖风景名胜区为案例,分析园林管理所获得的可用生物量及其生产生物能源的潜力.通过实地测定和问卷调查,研究表明:单位绿地面积园林废弃生物量为(4.60±3.12)t·hm-2·a-1;道路区域绿地的单位面积废弃物产量最高,干重平均值为5.96t·hm-2·a-1;产生绿化废弃物的主要植物种类有香樟(Cinnamomum camphora)、桂(Osmanthus fragrans)、杜鹃(Rhododendron simsii)等;园林废弃物总量干重为3402 t·a-1,可产生能量6.3×1010 kJ·a-1,理论上可以抵消景区40％的电能消耗;园林废弃物转化为生物能源适宜采用固体成型生物燃料技术;利用园林废弃物生产生物能源替代化石燃料每年可减排CO2 4177 t.开发利用景区园林废弃物生产生物能源,可实现减轻环境压力和增加生物能源供应的双赢.     

Silica-based solid phases for affinity chromatography: Effect of pore size and ligand location upon biochemical productivity

The influence of pore size and surface chemistry upon the productivity in affinity chromatography of three silica-based solid phases, Sorbsil C-200, C-500, and C-1000 (40-60 mum particle diameter and the corresponding pore diameters of 20, 50, and 100 nm), was studied using three model ligand/biomolecule systems of varying molecular masses. These studies revealed two unique parameters, biochemical productivity and maximum physical capacity, of the matrix as generically essential in the successful design and operation of productive affinity chromatography systems. Biochemical productivity, the molar ratio of the amount of product recovered per unit volume of adsorbent and ligand concentration, utilized the expected stoichiometry of binding of the two molecules to assess the efficacy of the adsorbent. This parameter, determined by equilibrium binding in batch suspensions and by saturation binding capacities and recoveries in fixed beds, yielded the optimum ligand concentration required for maximal performance. Maximum physical capacity, of the adsorbent to accommodate the biomolecules, was calculated from pore and molecular dimensions assuming that there was no steric hindrance to access. Using an immobilized human-IgG (Hu-IgG)/anti-Hu-IgG monoclonal antibody (MCAB) system, in which both the ligand and the product are of the same size (150 kDa), it was shown that the physical capacity of C-200 was only 16% of the theoretically expected amount. This capacity increased to 70 and 90% of the expected value with C-500 and C-1000, respectively, as the steric hindrance to protein penetration induced by pore dimensions decreased. The distribution of immobilized Hu-IgG within individual particles, visualized by immunofluorescence and immunogold labeling, showed that the ligand was restricted to the peripheral 3 mum of the C-200 particles (12% radius). In contrast, it was present throughout the C-1000 particles, indicating that there was no hindrance to access in this solid phase. The C-200 was suitable for use in a small ligand/biomolecule system studied (immobilized trypsin-inhibitor binding trypsin; 22.1 and 23.3 kDa, respectively) for which more than 60% of the maximum physical capacity was available for interactions. The C-500 proved satisfactory for the Hu-IgG/MCAB model system but showed steric limitations when an immobilized anti-beta-galactosidase MCAB (anti-beta-gal) was used to purify a larger product (beta-galacosidase; 460 kDa). The binding capacity and overall productivity of Hu-IgG- and anti-beta-gal-C-1000 was equivalent to that of Sepharose CL-4B. Selection of matrices with pore sizes appropriate to the dimensions of the ligand and product was, therefore, important. Finally, the Sorbsil silicas packed easily into beds and were used successfully with conventional chromatography equipment for low-pressure affinity chromatography. They therefore offer an ideal alternative to silica-based high-performance liquid affinity chromatography and soft-gel supports. (c) 1992 John Wiley & Sons, Inc.     

Effect of organic carbon,C:N ratio and light on the growth and lipid productivity of microalgae/cyanobacteria coculture

Current culture methods based on monocultures under phototrophic regimes are prone to contamination, predation, and collapse. Native cultures of multiple species are adapted to the local conditions and are more robust against contamination and predation. Growth, lipid and biomass productivity of a Louisiana native coculture of microalgae (Chlorella vulgaris) and cyanobacteria (Leptolyngbya sp.) in heterotrophic and mixotrophic regimes were investigated. Dextrose and sodium acetate at C:N ratios of 15:1 and 30:1 under heterotrophic (dark) and mixotrophic (400 μmol m^?2 s^?1) regimes were compared with autotrophic controls. The carbon source and C:N ratio impacted growth and biomass productivity. Mixotrophic cultures with sodium acetate (C:N 15:1) resulted in the highest mean biomass productivity (156 g m^?3 d^?1) and neutral lipid productivity (24.07 g m^?3 d^?1). The maximum net specific growth rate (U) was higher (0.97 d^?1) in mixotrophic cultures with dextrose (C:N 15:1) but could not be sustained resulting in lower total biomass than in mixotrophic cultures with acetate (C:N 15:1), with a U of 0.67 d^?1. The ability of the Louisiana coculture to use organic carbon for biomass and lipid production makes it a viable feedstock for biofuels and bioproducts.     

青海大通退耕还林工程区主要造林树种生产潜力

通过对青海大通退耕还林工程区主要树种的气候生产潜力、现实生产潜力和实际生产力进行研究 ,揭示了该地区主要造林树种在实际存在的气候条件下可能达到的理论产量 ,当前技术经济管理水平条件下所能达到的最高产量 ,现行经营管理条件下所获得的实际产量 ;分析了目前林业的现实生产潜力、实际生产潜力分别与气候生产潜力之间的差距 ,预示了该地区林业的发展前景 ;从合理利用气候资源和充分发挥土地生产潜力角度 ,提出了退耕还林工程建设中优选的树种及其原则 ;指出了不同树种在经营管理水平上的差异及其解决建议。其结果对该地区退耕还林工程的具体实施具有重要的实践指导意义     

Productivity of forests in the Eurosiberian boreal region and their potential to act as a carbon sink –- a synthesis

Based on review and original data, this synthesis investigates carbon pools and fluxes of Siberian and European forests (600 and 300 million ha, respectively). We examine the productivity of ecosystems, expressed as positive rate when the amount of carbon in the ecosystem increases, while (following micrometeorological convention) downward fluxes from the atmosphere to the vegetation (NEE = Net Ecosystem Exchange) are expressed as negative numbers. Productivity parameters are Net Primary Productivity (NPP=whole plant growth), Net Ecosystem Productivity (NEP = CO₂ assimilation minus ecosystem respiration), and Net Biome Productivity (NBP = NEP minus carbon losses through disturbances bypassing respiration, e.g. by fire and logging). Based on chronosequence studies and national forestry statistics we estimate a low average NPP for boreal forests in Siberia: 123 gC m^–2 y^–1. This contrasts with a similar calculation for Europe which suggests a much higher average NPP of 460 gC m^–2 y^–1 for the forests there. Despite a smaller area, European forests have a higher total NPP than Siberia (1.2–1.6 vs. 0.6–0.9 × 10¹⁵ gC region^–1 y^–1). This arises as a consequence of differences in growing season length, climate and nutrition. For a chronosequence of Pinus sylvestris stands studied in central Siberia during summer, NEE was most negative in a 67-y old stand regenerating after fire (– 192 mmol m^–2 d^–1) which is close to NEE in a cultivated forest of Germany (– 210 mmol m^–2 d^–1). Considerable net ecosystem CO₂-uptake was also measured in Siberia in 200- and 215-y old stands (NEE:174 and – 63 mmol m^–2 d^–1) while NEP of 7- and 13-y old logging areas were close to the ecosystem compensation point. Two Siberian bogs and a bog in European Russia were also significant carbon sinks (– 102 to – 104 mmol m^–2 d^–1). Integrated over a growing season (June to September) we measured a total growing season NEE of – 14 mol m^–2 summer^–1 (– 168 gC m^–2 summer^–1) in a 200-y Siberian pine stand and – 5 mol m^–2 summer^–1 (– 60 gC m^–2 summer^–1) in Siberian and European Russian bogs. By contrast, over the same period, a spruce forest in European Russia was a carbon source to the atmosphere of (NEE: + 7 mol m^–2 summer^–1 = + 84 gC m^–2 summer^–1). Two years after a windthrow in European Russia, with all trees being uplifted and few successional species, lost 16 mol C m^–2 to the atmosphere over a 3-month in summer, compared to the cumulative NEE over a growing season in a German forest of – 15.5 mol m^–2 summer^–1 (– 186 gC m^–2 summer^–1; European flux network annual averaged – 205 gC m^–2 y^–1). Differences in CO₂-exchange rates coincided with differences in the Bowen ratio, with logging areas partitioning most incoming radiation into sensible heat whereas bogs partitioned most into evaporation (latent heat). Effects of these different surface energy exchanges on local climate (convective storms and fires) and comparisons with the Canadian BOREAS experiment are discussed. Following a classification of disturbances and their effects on ecosystem carbon balances, fire and logging are discussed as the main processes causing carbon losses that bypass heterotrophic respiration in Siberia. Following two approaches, NBP was estimated to be only about 13–16 mmol m^–2 y^–1 for Siberia. It may reach 67 mmol m^–2 y^–1 in North America, and about 140–400 mmol m^–2 y^–1 in Scandinavia. We conclude that fire speeds up the carbon cycle, but that it results also in long-term carbon sequestration by charcoal formation. For at least 14 years after logging, regrowth forests remain net sources of CO₂ to the atmosphere. This has important implications regarding the effects of Siberian forest management on atmospheric concentrations. For many years after logging has taken place, regrowth forests remain weaker sinks for atmospheric CO₂ than are nearby old-growth forests.     

作物光能和光温生产潜力计算模式及其应用——以杭州市早稻和晚稻生产为例

在综合了前人研究和实地试验的基础上，提出了水稻生长发育温度隶属函数的评价指标体系，建立了水稻光能和光温生产潜力的计算模式，确定了相关参数，并以杭州市早稻和晚稻生产为例进行了光能和光温生产潜力的计算与分析。     

In situ measurements of net primary production in a Colorado mountain stream

Six stations were established on a Colorado mountain stream, and net primary productivity was measured in situ during all seasons. For 24-hour periods the dissolved oxygen and temperature of the water were electronically monitored over an undisturbed 1 x 1 m section of rubble bottom enclosed by a large plastic dome tightly fitted to the substrate. A submerged pump maintained a current within the dome, and the whole apparatus was submerged below the stream level. The bottom community net metabolism varied between heterotrophy and autotrophy with no correlations with altitude, season, light, water chemistry, and temperature. Readings were all very low and ranged from -27.38 to 35.59 grams of carbon fixed per square meter per year. There were no correlations between biomass of the bottom fauna and net community productivity.Contribution No. 71, University of Colorado Limnology Laboratory     

生物生产力的“4P”概念、估算及其相互关系

生物生产力是指从个体、群体到生态系统、区域乃至生物圈等不同生命层次的物质生产能力,它决定着系统的物质循环和能量流动,也是指示系统健康状况的重要指标。表示生物生产力的概念有总初级生产力（GP P）、净初级生产力（NPP）、净态生态系统生产力（NEP）和净生物群区生产力（NBP）,本文简称“4P”。主要探讨了“4P”概念的内涵和估算以及全球变化对它们的影响;通过生态系统的碳循环,建立“4P” 之间的相互联系,并对若干衍生概念进行定义。尽管生态系统的最终产物（NBP或现存量）占光合总产量的很少一部分,但它是决定物质再生物的资本,维持和决定生态系统的物质再生产。     

Kinetics and thermodynamics of ethanol production by a thermotolerant mutant of Saccharomyces cerevisiae in a microprocessor-controlled bioreactor

AIMS: The present investigation deals with the development of thermotolerant mutant strain of yeast for studying enhanced productivity of ethanol from molasses in a fully controlled bioreactor. METHODS AND RESULTS: The parental culture of Saccharomyces cerevisiae ATCC 26602 was mutated using UV treatment. A single thermotolerant mutant was isolated after extensive screening and optimization, and grown on molasses medium in liquid cultures. The mutant was 1.45-fold improved than its wild parent with respect to ethanol productivity (7.2 g l-1 h-1), product yield (0.44 g ethanol g-1 substrate utilized) and specific ethanol yield (19.0 g ethanol g-1 cells). The improved ethanol productivity was directly correlated with titres of intracellular and extracellular invertase activities. The mutant supported higher volumetric and product yield of ethanol, significantly (P相似文献   

放牧对草地群落与土壤特征的影响

针对放牧干扰对草地生态系统的影响,采用回归分析和典型对应分析(CCA)方法,研究放牧对草地植物群落物种多样性与生产力、土壤碳氮含量与生物量关系的影响。结果表明:(1)与休牧草地相比,放牧草地的地上生物量降低31.63%,凋落物生物量降低134.29%;放牧草地的禾草类生物量提高19.77%,而杂草类生物量和豆科类生物量分别降低31.09%和23.42%。(2)当物种多样性指数小于1.3时,休牧草地的生产力明显高于放牧草地;当物种多样性指数大于1.3时,放牧草地的生产力高于休牧草地。(3)CCA分析显示,家畜主要通过影响群落地上生物量、凋落物质量和土壤容重进而影响土壤的碳氮含量。(4)当群落地上生物量小于100g·m-2时,休牧草地的土壤有机碳和全氮含量高于放牧草地,当群落地上生物量大于100g·m-2时,放牧草地则略高于休牧草地。(5)当群落地下生物量小于1 200g·m-2时,放牧草地土壤有机碳、全氮含量高于休牧草地;当地下生物量大于1 200g·m-2时,放牧草地则略低于休牧草地。