甘肃省森林生态系统保育土壤功能及其价值评估

为更加直观地认识森林的重要生态和经济地位,并为甘肃省生态经济建设的综合决策提供科学的理论依据,实现生态经济可持续发展。以甘肃省重点林区为研究对象,采用物质量和价值量相结合的评价方法,定量地评价甘肃省森林生态系统保育土壤功能和经济价值。结果显示：（1）甘肃省森林生态系统年固土总量为16 620.53万t,年固土总价值为22.10亿元;年保肥总量为988.56万t,年保肥总价值为356.71亿元,森林生态系统年保肥价值占到总固土保肥总价值的94.2%,森林生态系统保肥所产生的价值远远大于固土所产生的价值,占据了主导地位;森林生态系统固土保肥总价值为380.80亿元/年,占甘肃省森林生态系统服务总价值（1 825.92亿元/年）的20.86%。（2）所选取的19种林分类型中,灌木林（222.10亿元/年）在整个森林生态系统固土保肥总价值中占据支配地位,占到总价值的58.32%;乔木林中,其他硬阔类（30.27亿元/年）、栎类（24.25亿元/年）、阔叶混交林（22.22亿元/年）三者固土保肥功能和产生价值较大。甘肃省森林生态系统保育土壤功能及其价值在整个森林生态系统服务中起到至关重要的作用,尤其是灌木林、其他硬阔类、栎类以及阔叶混交林提供的生态系统服务占据优势。     

沙化封禁区农田生态系统服务价值变化及其影响因素——以河西走廊8县市为例

[目的]对沙化封禁区农田生态系统服务进行研究,为干旱区生态安全和农户生计可持续发展提供支持。[方法]运用生态经济学方法和多元逐步回归模型,据此揭示河西走廊沙化封禁区所在8县市农田生态系统服务价值变化以及影响因素。[结果](1)沙化封禁区农田生态系统单位面积服务价值由19 966元/hm2增长到21 511元/hm2,增加了1 545元/hm2,年均增幅0.58%,原材料生产、废物处理、土壤形成和保护服务、食物生产是主要贡献类型;(2)农田生态系统总服务价值由29.40亿元增长到42.49亿元,增长了13.09亿元,年均增幅为2.88%,基本服务价值、社会保障服务价值大于水资源消耗服务价值和环境污染服务价值,但是水资源消耗和环境污染服务价值的增长速度明显加快;(3)8县市农田生态系统单位面积服务价值变化存在空间和类型差异,主要受农业生产总值、农民人均收入、化肥使用量、经济作物面积、粮食单产的影响。[结论]生态退化逆转对大部分县市的农田生态服务价值产生积极影响,但农田水资源消耗和环境污染效应不断增大,导致沙化土地逆转的脆弱性仍然较高。     

怀来县农田生态系统服务价值分类评估

农田生态系统可以为人类提供各种农产品及多种间接生态服务功能。以河北省怀来县为例,借助GIS工具,从微地貌形态、土壤状况和土地利用类型3个方面选取相应指标,将怀来县农田生态系统分为3个生态类及6个生态亚类,并且从生产服务、调节服务、文化服务和支持服务4个方面选取7个指标构建评估模型,分别对6种农田生态亚类进行生态系统服务价值测算和分析。结果显示,怀来县农田生态系统服务总价值为225 311.90万元,4种农田生态系统服务价值大小为生产服务文化服务调节服务支持服务;不同农田生态亚类的价值差异明显,其中Ⅱ—Ⅱ总价值最高,Ⅰ—Ⅰ最低;根据不同农田生态亚类价值功能组成比例,将6种农田生态亚类分为生产服务主导型和文化服务主导型两种类型,为怀来县未来因地制宜地发展区域农业、保护生态环境提供了参考。     

神农架林区大九湖湿地生态系统服务价值评价

[目的]评估神农架林区大九湖湿地生态系统服务功能价值,为湿地保护与管理提供科技支撑。[方法]收集现有数据,采用资源经济学和生态经济学原理,评估神农架大九湖湿地生态系统8项服务功能价值。[结果]神农架大九湖湿地生态系统服务总价值量为6.53亿元,约占神农架林区2015年度国内生产总值(GDP)的30%,其中以调蓄洪水、土壤保持和休闲娱乐3项服务价值为主导,占总价值的88.94%;科研教育服务价值仅占总价值量的0.47%,但其价值不可忽视。[结论]大九湖湿地生态系统服务总价值量突显了湿地保护的重要性,在一定程度上,湿地萎缩和功能退化与人类社会对湿地生态服务功能的认识程度有着密不可分的联系。     

玛纳斯河流域农田生态系统服务功能价值评估

农田生态系统可为人类提供各种产品及多种间接生态系统服务功能.本文运用环境经济学,借助GIS技术,对玛纳斯河流域农田生态系统1976年和2005年两个时段的产品提供、气候调节、土壤保持、碳固定、02释放以及营养物质保持等6项生态系统服务功能价值进行了物质量及价值量的估算和分析.结果表明.农田生态系统服务功能总价值从1976年的352 219.4×104元上升到2005年的767 061.5×104元,29年间上升117%.根据两个时段农田生态系统服务功能价值的分析,农田生态系统的产品提供功能受人类技术和管理的影响较大,具有较高的提升潜力,其价值占总生态系统服务功能价值的比例从1976年的7%上升到2005年的39%;而间接生态系统服务功能体现了农田生态系统的自然属性,为人类提供了巨大的调节、支持服务功能,从1976年至2005年,其生态系统服务功能价值上升43%.玛纳斯河流域农田生态系统服务功能研究表明,农田生态系统具有多种生态系统服务功能,应该重视对农田生态系统各项生态系统服务功能价值的评估,从而达到干旱区流域社会、经济、自然生态系统的和谐发展.     

农田生态系统服务及其价值的研究进展

农田生态系统在人类控制下已逐渐演变成了提供农产品的集约化生产系统。尽管与自然生态系统相比, 农田生态系统服务功能有所下降, 但其在提供农产品的同时还在向人类提供大量的生态服务。近年来, 生态系统服务稀缺性变得越来越突出, 农田生态系统的多功能性受到了空前的重视。本文首先明确了农田生物多样性是农田提供多种生态系统服务的基础, 然后回顾了2000年以来国内外农田生态系统服务及其价值化领域取得的主要研究进展, 包括对农田产品供给、碳汇、土壤保持和养分循环、水调节等功能的评价以及对农田生态系统服务及其价值化的综合研究。与此同时, 我们也应该注意到农业生产还对人类社会和自然环境产生了各种消极影响, 认识到权衡农田生态系统在农业生产中的各项利弊的重要性。通过对比不同农业生产模式对农田生态系统服务供给的影响, 提出未来发展多功能农业将是实现农田对人类福祉最大化的重要方向。最后, 文章指出我国发展多功能农业的主要措施是: (1)确保18亿亩耕地在空间上的存在; (2)与森林、草地、湿地、水域等其他自然生态系统在空间上合理配置; (3)在农业区域充分发展以观光休闲功能为主的休闲农业, 实现农田生态系统社会文化价值; (4)逐步实施农业生态补偿。     

白龟山水库生态系统服务功能价值评估研究

白龟山水库是河南省平顶山市的主要供水水源。基于生态服务价值原理和当地实际,对该水库湿地生态系统的生态价值进行了评估。结果表明:该水库直接的物质生产价值为17.757亿元人民币,水库消落带土壤和植被固碳释氧总价值为1.424亿元人民币,在提供野生生物栖息地、维护生物多样性等服务功能方面的年生态效益为0.221亿元人民币,调蓄洪水功能价值为6.177亿元人民币,水资源蓄积功能价值为3.551亿元人民币,水库净化水质总价值为0.816亿元人民币。该水库湿地生态系统,在全部发挥效益后每年所产生的生态服务价值总额为29.946亿元人民币。除了供水功能外,水库的调蓄洪水功能价值最为突出,其次是水资源蓄积功能价值。     

基于土地利用的甘州区生态系统服务价值研究

以张掖市甘州区为研究对象,采用1987年、2000年、2009年3期土地利用数据,分析了甘州区1987—2009年在土地利用/覆盖变化驱动下的生态系统服务价值变化。研究表明:（1）甘州区农田和居民工矿用地一直处于增加趋势,林地和草地先减少后增加,水域处于减少状态;（2）甘州区生态系统服务价值呈现先降后升的“V”字形变化,1987年、2000年和2009年3个年份分别是25.2,19.53,20.21亿元;在不同生态系统类型中,农田、草地、水域提供的生态功能服务价值达到总价值的80%以上,在生态系统服务价值构成中占有重要地位;（3）生态系统单项服务功能价值中,水源涵养和废物处理的生态功能服务价值较高,二者之和占总价值的近40%;（4）各土地利用类型生态系统服务价值敏感性指数都小于1,表明甘州区生态系统服务价值缺乏弹性,研究结果可信;（5）从表面看,生态系统服务价值的变化直接源于土地利用的变化。实质上,在土地利用变化的背后隐含着不同时期人类活动强度和政府政策导向的间接驱动。     

高原生态城土地利用变化对生态系统服务价值的影响研究——以甘肃省民乐县为例

采用Constanza生态系统服务价值计算公式,结合谢高地等人制定的中国陆地生态系统单位面积生态服务价值表,对正在建设高原生态城的民乐县1996—2020年25a间的土地利用变更数据进行分析,估算了民乐县的生态系统服务价值,并对其变化进行对比分析。结果表明:①1996—2009年,民乐县的生态系统服务价值从9.5079亿元增加到10.019 3亿元,预测到2015年和2020年将分别达到10.559 4亿元和10.712 9亿元,区域生态系统服务价值呈增加趋势。②在不同生态系统类型中,森林、草地和农田生态系统提供的生态系统服务价值所占比例较大,而林地面积的增加是引起其生态系统服务总价值持续上升的主要原因。     

保障粮食安全造成的生态服务价值损失初探

在阐明保障粮食安全造成的生态服务价值损失内涵的基础上, 分析了保障粮食安全造成的生态服务价值损失的类型。研究结果表明: 保障粮食安全造成的生态服务价值损失分为直接损失和间接损失。直接损失包括两方面, 一是粮食生产过程中, 土地利用结构的调整使不同生态系统之间发生合理转换所引起的生态服务价值损失; 二是由于粮食生产对农田生态系统周围的生态系统产生负面影响, 造成其生态服务价值的损失。间接损失是指土地作为粮食生产用地, 而不是生态服务价值更大的土地利用类型(或生态系统类型), 所产生的生态服务价值损失。     

低氮和干旱胁迫对富士和秦冠生长及氮素利用的影响

【目的】以富士（Fuji）、 秦冠（Qinguan）嫁接在平邑甜茶（Malus hupehensis Rehd.）上的当年生盆栽苗为试验材料,采用砂培方法,研究了缺氮胁迫和干旱对富士和秦冠生长情况、 光合参数、 植株各部位氮磷钾含量及氮素利用效率的影响,分析比较了低氮干旱条件下富士和秦冠生长及氮素利用的差异,以期为果树生产高效肥水利用提供理论指导。【方法】试验共设四个处理: 正常氮正常水（ZZ）、 低氮正常水（DZ）、 正常氮干旱（ZG）、 低氮干旱（DG）。氮素和水分均设置两个水平,分别为正常氮（6 mmol/L NO-3-N）、 低氮（0.3 mmol/LNO-3-N）、 正常供水（保持盆中砂子相对含水量为饱和含水量的80%~85%）、 干旱处理（保持盆中砂子相对含水量为饱和含水量的60%~65%）。【结果】富士和秦冠的生物量（茎和叶）、 株高茎粗等生长指标以及光合速率、 气孔导度、 蒸腾速率均为正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）,并且相对应处理下秦冠的以上指标均高于富士;正常供水下,缺氮处理使富士、 秦冠的根冠比比正常氮处理均有所增加,富士提高了2.05%,秦冠提高了22.40%。富士和秦冠的氮、 磷、 钾含量均表现出正常氮正常水（ZZ）＞低氮正常水（DZ）＞正常氮干旱（ZG）＞低氮干旱（DG）; 氮、 钾元素含量在植株各部位的分布顺序依次是叶＞根＞茎,磷元素则是根＞叶＞茎;光合氮素利用效率（PNUE）和氮素利用效率表现为秦冠处理之间差异极显著,富士处理之间差异不显著;秦冠的PNUE和NUE明显高于富士,在低氮正常水（DZ）处理下,秦冠氮肥利用率比富士高42.07%,在低氮干旱（DG）处理下高64.14%;低氮胁迫下富士和秦冠的NUE显著提高,并且秦冠提高的幅度高于富士。【结论】施用氮肥能够显著提高富士与秦冠的干物质量,同等水肥条件下,秦冠生长优于富士;水分亏缺会减少叶片对氮的吸收,干旱条件下适度增施氮肥,可提高果树的抗旱能力;低氮干旱胁迫下秦冠的生长指标、 光合指标及氮素利用效率指标均优于富士,表现出较强的抗低氮干旱胁迫的能力。     

Pasture Vegetation Elemental Analysis by Laser-Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy (LIBS) is a new technique for the analysis of plant material. This study investigates the application of LIBS to pasture-based plant samples. The LIBS measurements were obtained from pelletized pasture samples (100 samples) that had been also analyzed by inductively coupled plasma–optical emission spectroscopy (ICP-OES) following microwave digestion for calibration and comparison purposes. Comparisons for elements sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), boron (B), phosphorus (P), and sulfur (S) showed that LIBS could be used for almost all the standard profile total elements with concentrations down to low mg/kg levels (observed error of Na: 0.024 percent, K: 0.18 percent, Mg: 0.016 percent, Ca: 0.073 percent, P: 0.017 percent, Mn: 31 mg/kg, Fe: 150 mg/kg, Zn: 6.6 mg/kg, and B: 1.1 mg/kg). Elemental analysis at less than mg/kg levels was not possible using LIBS. The elements S and Cu were particularly difficult to analyze with reliability using LIBS at the concentration levels found in the plant samples. Replacing microwave digestion and subsequent ICP analysis with a direct analysis of dried plant samples using LIBS has the potential to improve the productivity and reduce the cost of testing.     

Faculty positions:Center for Agricultural Resources Research,Chinese Academy of Sciences

正The Center for Agricultural Resources Research(CARR),the Institute of Genetics and Developmental Biology(IGDB),Chinese Academy of Sciences,invites applicants for several research group leader positions.CARR is one of the research organizations in Chinese Academy of Sciences(CAS).We seek nominations and applications from individuals who have expertise and a record of accomplishment in research areas related to ecology,agro-hydrology,     

Macroinvertebrates in North American tallgrass prairie soils: effects of fire, mowing, and fertilization on density and biomass

The responses of tallgrass prairie plant communities and ecosystem processes to fire and grazing are well characterized. However, responses of invertebrate consumer groups, and particularly soil-dwelling organisms, to these disturbances are not well known. At Konza Prairie Biological Station, we sampled soil macroinvertebrates in 1994 and 1999 as part of a long-term experiment designed to examine the effects and interactions of annual fire, mowing, and fertilization (N and P) on prairie soil communities and processes. For nearly all taxa, in both years, responses were characterized by significant treatment interactions, but some general patterns were evident. Introduced European earthworms (Aporrectodea spp. and Octolasion spp.) were most abundant in plots where fire was excluded, and the proportion of the total earthworm community consisting of introduced earthworms was greater in unburned, unmowed, and fertilized plots. Nymphs of two Cicada genera were collected (Cicadetta spp. and Tibicen spp.). Cicadetta nymphs were more abundant in burned plots, but mowing reduced their abundance. Tibicen nymphs were collected almost exclusively from unburned plots. Treatment effects on herbivorous beetle larvae (Scarabaeidae, Elateridae, and Curculionidae) were variable, but nutrient additions (N or P) usually resulted in greater densities, whereas mowing usually resulted in lower densities. Our results suggest that departures from historical disturbance regimes (i.e. frequent fire and grazing) may render soils more susceptible to increased numbers of European earthworms, and that interactions between fire, aboveground biomass removal, and vegetation responses affect the structure and composition of invertebrate communities in tallgrass prairie soils.     

Variation in quality parameters between and within 14 Nordic tree fruit and berry species

Abstract

A 3-year study was carried out to investigate quality parameters in 14 tree fruit and berry species grown in southern Norway. The species were blueberry, apple, aronia, sour cherry, sweet cherry, red raspberry, strawberry, blackcurrant, gooseberry, red currant and elderberry, harvested along with wild bilberry, cloudberry and lingonberry. Significant differences between species were identified for all quality parameters. The coefficient of variation between species was lowest for pH (12.5%), dry matter (18.9%) and soluble solids (25.3%), followed by titratable acids (59.3%), total phenolics (83.8%), antioxidant capacity FRAP (85.7%) and antiradical power by the DPPH-assay (97.8%), total monomeric anthocyanins (132%) and ascorbic acid (137%). Average coefficient of variation within species were lower and ranged from 4 (pH) to 62% (ascorbic acid). Only the FRAP values were significantly affected by harvesting year with lower levels in 2004 than in 2005 and 2006. There were significant interactions between species and harvesting year for dry matter, soluble solids, pH, ascorbic acid and FRAP. The results indicate generic ranges in composition within species independent upon growing location and climate, and the composition of the tree fruits and berries is not likely to deviate from these ranges. It is concluded that desirable composition of tree fruits and berries and their products should primarily be achieved by selection among species rather than searching fors broadened variation within individual species.     

Potassium Fixation and Release Characteristics in Rhizosphere and Nonrhizosphere Soils for a Rapeseed–Rice Cropping Sequence

Potassium (K) fixation and release in soil are important factors in the long-term sustainability of a cropping system. Changes in K concentration and characteristics of K fixation and release in rhizosphere and nonrhizosphere soils in the rapeseed (Brassica napus L.)–rice (Oryza sativa L.) rotation were investigated using a rhizobox system. The concentrations of different forms of K in both rhizosphere and nonrhizosphere soils decreased with plants compared to without plants, regardless of K fertilizer application. Potassium uptake by crops mainly came from the rhizosphere soil. In the treatment without K fertilizer (–K), the main form of K supplied by the soil to the crops was 1.0 mol L^?1 nitric acid (HNO₃) nonextractable K, followed by nonexchangeable K, and then exchangeable K. In the treatment with K fertilizer (+K), the main K forms supplied by the soil to the crops were exchangeable K and nonexchangeable K. The amount and rate of K fixation after one cycle of the rapeseed–rice rotation was greater in rhizosphere soil than in nonrhizosphere soil. The amount and rate of K fixation of soil in the +K treatment were significantly less than in the –K treatment. The cumulative amounts of K released with 1.0 mol L^?1 ammonium acetate (NH₄OAc) and 1.0 mol L^?1 HNO₃ extraction increased with the increasing numbers of extractions, but the K-releasing power of soil by successive extraction decreased gradually and finally became almost constant. The release of K was less in rhizosphere soil than in nonrhizosphere soil. The release of K in the +K treatment was similar to that in the –K treatment in rhizosphere soil, but the K release in nonrhizosphere soil was greater with the +K than the –K treatment. Overall, the information obtained in this study will be helpful in formulating more precise K fertilizer recommendations for certain soils.     

Electron donor and pH relationships for biologically enhanced dissolution of chlorinated solvent DNAPL in groundwater

Biologically enhanced dissolution offers a method to speed removal of chlorinated solvent dense non-aqueous-phase liquid (DNAPL) sources such as tetrachloroethene (PCE) and trichoroethene (TCE) from aquifers. Bioremediation is accomplished by adding an electron donor to the source zone where fermentation to intermediates leading to acetic acid and hydrogen results. The hydrogen and possibly acetic acid are used by dehalogenating bacteria to convert PCE and TCE to ethene and hydrochloric acid. Reductive dehalogenation is thus an acid forming process, and sufficient alkalinity must be present to maintain a near neutral pH. The bicarbonate alkalinity required to maintain pH above 6.5 is a function of the electron donor: 800 mg/L of bicarbonate alkalinity is sufficient to achieve about 1.2 mM TCE dechlorination with glucose, 1.7 mM with lactate, and a much higher 3.3 mM with formate. Laboratory studies indicate that in mixed culture, formate can be used as an electron donor for complete conversion to ethene, contrary to pure cultures studies indicating it cannot. Various strategies can be used to add electron donor to an aquifer for DNAPL dehalogenation while minimizing pH problems and excessive electron donor usage, including use of injection-extraction wells, dual recirculation wells, and nested injection-extraction wells.     

Biodiversity and ecogeography of wild Lactuca spp. in some European countries

Staff members of the Department of Botany of Palacký University in Olomouc and Gene Bank Department – Workplace Olomouc, Research Institute of Crop Production in Prague, Czech Republic, conducted an expedition in seven European countries (Austria, Czech Republic, France, Germany, Italy, the Netherlands, Switzerland) in August/September 1999 to collect wild Lactuca spp. germplasm and study its geographic distribution, ecology and biodiversity. During the mission, more than 600 locations were visited resulting in the collection of 602 seed samples (accessions) of wild Lactuca species and 13 seed samples of related genera (Chondrilla and Mycelis). Lactuca serriola f. serriola, L. serriola f. integrifolia, L. saligna and L. viminea subsp. chondrilliflora were prevalent in southern Europe (Italy, France), however, only L. serriola was common in central and western Europe (Austria, Czech Republic, Germany, Netherlands, Switzerland). The greatest diversity of Lactuca species was found in France, where also the most seed samples (165) were collected. The most characteristic habitats with a high density of Lactuca spp. populations were observed along roads and highways, grassy ditches, ruderal communities, and dust-heaps. Natural infections by powdery mildew (Erysiphe cichoracearum) and downy mildew (Bremia lactucae) on some wild Lactuca spp. were observed. Recent observations concerning the geographic distribution, population structure, habitats, and natural occurrence of diseases of Lactuca spp. are discussed. This assemblage of genetic resources of Lactuca spp. can serve as the basis of future studies of species diversification, spatial population structure, plant microevolution, domestication processes, and genetic variability of host-parasite interactions.     

Increase in auxiliary photoprotective photosynthetic pigments in wheat seedlings induced by Azospirillum brasilense

Inoculation of wheat seedlings with the plant growth-promoting bacterium Azospirillum brasilense Cd was immobilized in alginate microbeads and, without applying any stress, significantly increased the quantity of several photosynthetic pigments, such as chlorophyll a, chlorophyll b, and the auxiliary photoprotective pigments violaxanthin, zeaxanthin, antheroxanthin, lutein, neoxanthin, and β-carotene. This resulted in greener plants with no apparent visible stress. After monitoring the quantity of photosynthetic pigments for 4 weeks, we observed that inoculated plants had higher quantities of pigments in shoot and stem. The greatest difference in the quantity of all pigments between inoculated and noninoculated plants occurred in the first week of growth. Regardless of treatment, the quantity of pigments in stems was three to four times less than the quantity of these pigments in shoots. Application of Azospirillum, either as liquid inoculant or as alginate microbeads, did not alter the positive effect of the bacteria on pigment production or the positive response of the plants towards A. brasilense Cd inoculation.     

In-situ enrichment and analysis of atrazine-degrading microbial communities using atrazine-containing porous beads

We examined the community composition of microbes that colonized atrazine-containing beads buried in agricultural soils that differed in atrazine treatment history. Bacterial abundance was 5-40-fold greater in atrazine-fortified beads. In beads containing 20 mg atrazine kg⁻¹ buried in soil with a history of atrazine application (conditioned soil), the abundance of Actinobacteria increased approximately 80-fold whereas in control soil, Actinobacteria were enriched only 10-fold and the gamma-Proteobacteria and Planctomycetes increased by 60- and 25-fold, respectively. The gamma-Proteobacteria were enriched by 120- and 230-fold in beads containing 200 mg atrazine kg⁻¹ in conditioned and control soil, respectively. The results demonstrate that BioSep^® beads are a suitable matrix for recruiting a diverse subset of the bacterial community involved in atrazine degradation.