太湖地区高产水稻生命周期评价

以太湖地区高产水稻典型管理措施为例,应用生命周期评价方法,以生产1t水稻为评价的功能单元,把水稻生命周期划分为原料阶段、农资阶段和种植阶段进行清单分析与影响评价,考虑了能源消耗、水资源消耗、温室效应、环境酸化和富营养化5种环境影响类型。结果表明,太湖地区高产水稻生命周期环境影响潜力大小依次是水资源消耗、富营养化、温室效应、环境酸化和能源消耗,环境影响指数分别为1．45、0．54、O．52、0．32和0．05,环境影响综合指数为0．54。降低稻田水肥投入,提高水分和养分生产效率是控制太湖地区水稻生产体系生命周期环境影响的关键,它在直接减少种植环节资源消耗与污染排放的同时,也间接减轻了上游生产环节的环境影响,从而减缓生命周期的环境影响。     

基于开放式培养的微藻生物柴油生命周期环境影响评价

为定量评价以微藻为原料生产的生物柴油生命周期系统产生的各种潜在环境影响,以基于开放式培养的微藻生物柴油为研究对象,应用生命周期分析方法,以1 MJ能量的柴油产品为功能单位,对生产、使用微藻生物柴油产生的环境影响进行了分析。结果表明：微藻生物柴油生命周期最显著的环境影响类型为不可更新资源消耗,其次为光化学烟雾形成,生命周期总环境影响指数为4.63×10-4人当量,较石化柴油降低19.34%,以油菜籽为原料的生物柴油生命周期总环境影响指数是微藻生物柴油的7.19倍,微藻培养与生物柴油制取对生命周期总环境影响指数的贡献分别为27.95%与46.24%。基于开放式培养的微藻生物柴油相对于石化柴油与以油菜籽为原料的生物柴油具有较好的生命周期环境效益,控制微藻生物柴油生命周期环境影响的要点在于减少微藻培养与生物柴油制取阶段的动力消耗。     

辽宁省育肥猪生产环境影响的生命周期评价

采用生命周期评价方法,以1 000 头出栏育肥猪的规模化养殖场为功能单位,对辽宁地区育肥猪生产进行污染物排放清单分析,评价其环境影响。结果表明,1 000 头育肥猪生产的生命周期环境影响综合指数为56.59,环境影响大小依次为富营养化、酸化、全球变暖,环境影响指数依次为36.31、13.84和6.44;富营养化影响主要来源于猪粪尿中氮、磷的排放,酸化影响主要来源于猪粪尿中NH3的排放,全球变暖影响主要来源于种植饲料作物使用的化肥生产过程中NOx的排放。因此,加强养猪粪污无害化处理,促进养殖业废物资源化,增加育肥猪饲料中青饲料比例,提高饲料作物生产过程中化肥利用率是降低辽宁地区育肥猪生产环境负荷的主要措施。     

中国虹鳟养殖模式的生命周期评价

本文以黑龙江省和北京市虹鳟养殖为例,应用生命周期评价方法,将虹鳟养殖生命周期划分为饵料生产、电力生产、化学品生产和养殖污染排放4个阶段,考虑了全球变暖潜势、能源消耗、酸化潜值和富营养化潜值4种环境影响类型,以获得1t养殖增重量为评价的功能单位,对虹鳟网箱养殖模式、工厂化流水养殖模式和工厂化循环水养殖模式的潜在环境影响进行了评价比较。结果表明,我国虹鳟养殖模式的环境影响从高到底依次是富营养化潜值、全球变暖潜势、酸化潜值和能源消耗;网箱养殖模式的环境影响指数分别为53.963、0.939、0.717和0.017,工厂化流水养殖模式的环境影响指数分别为35.213、4.827、2.896和0.049,工厂化循环水养殖模式的环境影响指数分别为7.404、5.545、3.305和0.055;富营养化潜值是虹鳟养殖的主要环境影响类型,其主要来自养殖污染排放。3种虹鳟养殖模式的环境影响综合指数分别为6.69、5.52和2.02,我国虹鳟养殖模式的环境性能从高到低依次为工厂化循环水养殖模式〉工厂化流水养殖模式〉网箱养殖模式。减少养殖污染排放、降低电能消耗和提高饵料利用率是提升我国虹鳟养殖模式环境友好性的关键。     

两种水稻生产方式的生命周期环境影响评价

以湖南水稻生产体系为例,应用生命周期评价方法,对两种水稻生产方式进行生命周期资源消耗与污染物排放清单分析,在此基础上进行了生命周期环境影响评价。结果表明,两种生产管理措施下潜在环境影响较大的均是富营养化、水体毒素、土壤毒素和环境酸化,其中传统生产方式下4项潜在环境影响指数分别为1．606、0．868、0．309和0．262,推荐生产方式下各项环境影响指数分别下降至1．277、0．489、0．260和0．211。经加权评估后,两种模式的生命周期环境影响综合指数分别为0．3634和0．2676。潜在富营养化主要来自于作物种植阶段农田NH3挥发和NO3-N淋失;水体毒素和土壤毒素主要来自农药使用;环境酸化主要来自施氮导致的NH3挥发和农用化学品生产中排放的SOx。水稻生产的管理方式需要在推荐生产方式的基础上做重大改进,实施清洁生产方式,减少氮肥、农药的使用量,是控制水稻生命周期环境影响的关键。     

京郊典型作物生产体系施肥环境影响的生命周期评价

以北京市顺义区冬小麦-夏玉米轮作和露地蔬菜两种作物生产体系为对象,采用生命周期评价（LCA）方法,综合考虑全球变暖、环境酸化、水体富营养化、土壤毒性、能源消耗和淡水资源消耗6种环境影响类型,分别以年产1t作物产品干物质和种植1hm2作物为评价功能单元,系统研究了施肥的资源环境影响潜力。结果表明：对于大田作物和露地蔬菜生产系统,年产1t产品（干物质）施肥的综合环境影响指数分别为0.46和2.11,种植1hm2作物施肥的综合环境影响指数则分别为4.74和26.77;农田种植环节环境影响潜力的贡献分别占大田作物和露地蔬菜整个生命周期环境影响潜值的95.1%和99.1%,远远大于肥料生产环节;大田作物和露地蔬菜生产过程中的环境影响潜力均表现为水体富营养化〉环境酸化〉全球变暖〉淡水资源消耗〉能源消耗〉土壤毒性;肥料氨挥发是引起水体富营养化和环境酸化的主要途径,硝态氮和总磷的淋洗径流损失也是水体富营养化的主要来源。优化施肥量是控制作物生产施肥潜在环境影响的关键。     

水葫芦能源利用的生命周期环境影响评价

水葫芦厌氧发酵能源化利用已成为水葫芦处理与资源化利用的一个重要途径,以江苏省农业科学院水葫芦中试基地与常州市武进区水葫芦综合利用示范工程为案例,利用生命周期评价的方法建立水葫芦厌氧发酵产沼气工程污染物排放的清单,并对系统生命周期环境影响进行评价,以水葫芦能源利用产生1MWh电能为功能单位,评价其对环境产生的影响。研究过程将整个生命周期分成3个阶段：水葫芦厌氧发酵预处理、水葫芦厌氧发酵产沼气发电和沼液沼渣农田应用,重点考虑了3种环境影响类型：全球变暖、环境酸化和富营养化。评价结果为：各类型环境影响指数分别为2.1×10^-3、4.89×10^-2和1.98×10^-1,与能源作物发电及传统火力发电相比较,水葫芦厌氧发酵能源化利用中的CO2、SOx、NOx等污染物排放量均较低,对环境的负面影响最小,但水葫芦能源利用的生命周期效率仅为0.09,低于能源作物热电联用的技术途径（0.119）。降低水葫芦厌氧发酵能源化利用中的石化能源消耗、控制堆肥及沼液沼渣有机肥施用过程中氨挥发损失,对于提高水葫芦能源转化效率与降低环境影响指数至关重要。     

基于生命周期评价的楚雄市水稻生产环境影响评价

水稻种植会直接和间接造成环境问题。基于此,借助生命周期法,选取能源消耗、温室气体、富营养化和环境酸化4个指标对云南省楚雄州楚雄市水稻生产的环境影响进行评价,揭示该区域水稻生产中环境影响物质的来源、结构和贡献率,为该区域水稻生产的环境影响调控提供参考。结果表明:楚雄市水稻生产的能源消耗、温室气体、富营养化和环境酸化四个环境影响指标对应的环境影响潜值分别为2 432.496 MJ、979.814 kg CO_2-eq、11.381 kg PO_4~(3-)-eq和46.929 kg SO_2-eq;几种环境影响指标对应的环境影响严重程度排序为富营养化环境酸化温室气体能源消耗,对应的环境影响指数分别为6.054、0.898、0.134和0.094;楚雄市每生产1 t水稻产品系统环境影响值为1.685。氮肥的清洁生产和合理施用是降低该区域水稻生产造成环境影响的关键。     

食品生命周期评价方法及其应用研究

针对食品生命周期内产生的资源、能源消耗以及对环境的影响，将生命周期评价引入食品加工领域，从目标与范围定义、清单分析、影响评价和改善评价4个步骤初步构建了食品LCA方法体系。分析了中国开展食品LCA存在的问题以及相应的解决途径。以啤酒酿造过程为案例进行了评价研究。评价结果显示，该过程中各主要环境影响因子影响潜值依次为：富营养化(0.061)，工业烟尘和粉尘(0.015)，固体废弃物(0.003)，据此可分别建立有效的废水处理设施，改进物料粉碎方式，回收利用废硅藻土来相应减少环境影响。研究表明，开展食品LCA可以为提高食品环境性能提供有效的数据支持,对中国食品工业实现可持续发展具有重要意义。     

玉米与不同功能植物间作对环境的影响

以当前农业生产领域的热点问题N素污染为研究对象,在玉米种植中引入苜蓿、黑麦草、花生和大豆4种功能植物与其问作,试图通过植物修复手段达到减少N污染的目的。应用生命周期评价方法评价了不同种植模式对环境的影响。结果表明,5种种植模式对环境影响的大小依次为：玉米｜黑麦草〉玉米单作〉玉米｜花生〉玉米｜苜蓿〉玉米｜大豆模式,环境影响综合指数分别为0．1459、0．1295、0．1229、0．1136和0．0945。玉米｜花生、玉米｜苜蓿、玉米｜大豆模式可以有效地减小由于过量施用氮肥对环境造成的影响,而玉米｜黑麦草模式则加重了对环境的负面影响。说明选择适宜的功能植物（如花生、苜蓿和大豆）引入玉米群体可以有效减小过量施肥对环境的影响。     

“绿色革命”以来大气CO2浓度升高对C3作物营养品质的影响

自20世纪60年代"绿色革命"以来,育种技术和农耕技术的发展促进了农作物产量的大幅提升,然而作物的营养品质出现下降趋势。在相似的遗传背景下,大气CO_2浓度升高会使单位体积农作物产品的营养元素含量下降,因此"绿色革命"至今,农作物产品的营养元素下降可能受大气CO_2浓度升高影响。通过植物生长箱模拟"绿色革命"初期和目前的大气CO_2浓度水平(310μmol/mol和400μmol/mol),针对主要C_3作物水稻、小麦和大豆,研究"绿色革命"以来大气CO_2浓度升高对其籽粒的C、N、Fe、Zn元素含量的影响,结果表明:CO_2浓度升高对3种作物籽粒的C元素含量几乎没有影响,变化幅度在±1.5%之间;籽粒的N、Fe、Zn元素含量普遍呈现下降趋势,但均未达到显著水平。     

Potential of wild species for genetic enhancement of some semi-arid food crops

Discovery and incorporation of genes from wild species provide means to sustain crop improvement, particularly when levels of resistance in the cultigens are low and virulent strains of pests and pathogens overcome the host plant resistance. The extent of utilization and the potential of the wild genepool for genetic enhancement were reviewed in five important food crops viz. sorghum, pearl millet, chickpea, pigeonpea and groundnut grown in the semi-arid tropics. Introgression from compatible wild germplasm in the primary gene pool resulted in transfer of new cytoplasmic male sterility systems in pearl millet and pigeonpea, development of high protein, cleistogamous flower and dwarf pigeonpea lines and foliar disease resistant groundnut cultivars. Utilization of wild species in secondary and tertiary gene pools has been generally limited due to sterility, restricted recombination or cross incompatibility. Nevertheless, these species are extremely important as they contain high levels of resistance to several important biotic and abiotic stresses. Several of them, like those belonging to the Parasorghum section and the rhizomatous Arachis species are sources of multiple resistances and hold great promise to sustain crop productivity.     

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     

Soil-profile distribution of primary and secondary plant-available nutrients under conventional and no tillage

Nutrient distributions under no tillage (NT) compared with conventional disk-and-bed tillage (CT) management in the warm, humid region of the southeastern USA need to be assessed so that future placement, quantity, and type of fertilizers can be altered, if necessary, to efficiently match crop demands. We determined soil-profile distributions of pH, N, P, S, K, Ca, Mg, Na, Zn, Fe, Mn, and Cu to a depth of 0.9 m at the end of 8.5 years of continuous CT and NT management on a Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas. Most dramatic changes occurred within the 0–0.05 m depth, where soil under NT had lower pH, Fe, and Cu than under CT, but greater P, K, Zn, and Mn. Greater P and K under NT than under CT also occurred below the till-zone (0.15–0.3 m). At a depth of 0–0.3 m, soil under NT contained greater amounts of extractable P, K, Zn, Fe, Mn, and Cu than under CT. Nitrogen fertilization had little effect on nutrient distributions, except resulting in greater extractable K at 0–0.05 m and greater nitrate at 0–0.15 m. Few changes in soil-profile distributions were observed for extractable S, Ca, Mg, and Na. Long-term continuous use of NT on this fine-textured, high-fertility (except for N) soil had no apparent adverse effects on nutrient distributions relative to CT, but enhanced conservation and availability of P, K, Zn, Fe, Mn, and Cu near the soil surface where crop roots proliferate.     

Assessing the effectiveness of conservation measures: Resolving the “wicked” problem of the Steller sea lion

“Wicked” problems are those that are complex and that change when solutions are applied. Many conflicts in conservation fall into this category. The study approached the problem of how to constrain the apparent wickedness of a problem in the conservation management of a species by using simple empirical indicators to carry out iterative assessment of the risk to a population and to document how this risk evolves in relation to the addition of new data and the implementation of management actions. Effects of high levels of uncertainty within data and also concerning population structure were examined through stochastic simulation and by exploration of scenarios. Historical trends in the example used, the Steller sea lion, showed rapid declines in abundance in some regions during the 1980s. The current total population is 130,000-150,000 Steller sea lions through Alaska and British Columbia and this number has been stable since about 1990 in spite of regional differences in population dynamics. Regional differences in the sequence of changes in the number of pups and non-pups, suggested that an internal re-distribution of juveniles could have happened between 1980 and 1990. Current productivity also appears close to the long-term mean. Stochastic population projection using various scenarios showed that, based upon this history, the risk of extinction for the population has declined and is below reasonable thresholds for considering the population to be endangered. The trends in risk suggest that management actions taken since 1990 have probably been effective. Consequently, the conservation management objectives for the Steller sea lion are probably being met. The approach provides a mechanism, based upon experience and scenario analysis, for exploring future policy options and may help to constrain the debate amongst stakeholders about the cost-benefit trade-offs associated with different options.     

Collection and preliminary evaluation of native turfgrass accessions in Italy

Despite a raising interest on turfs in Italy, all theavailable varieties of this kind in the Country are of foreign origin, and areoften poorly adapted to the prevailing climatic conditions. This prompted tobegin a collection activity of indigenous turfgrass species, with the ultimategoal of identifying promising materials for future breeding based on localgenetic resources. The collection was carried out in three areas of Italy, viz.the northern Po Plain, the coastal region of Liguria, and the island of Sardiniathat are characterised, respectively, by subcontinental, warm temperate, andtypical Mediterranean climate. Altogether, 141 sites were visited, yielding 226accessions belonging to eight species of potential interest for turfs:Poa pratensis, Poa trivialis,Festuca rubra, Festuca arundinacea,Lolium perenne, Agrostis stolonifera,Agrostis tenuis, and Cynodon dactylon,this last being a warm-season grass. Poa pratensis andCynodon dactylon were mostly collected in northern Italyand Sardinia, respectively, whereas Festuca arundinacea andLolium perenne were rather ubiquitous. The collection sitesranged from 0 to 1040 m asl, but sites over 750 m wereonly visited in the inner part of Sardinia. All the accessions, collected aswhole plants, were transplanted at Lodi, northern Italy, where they are beingevaluated. Their preliminary evaluation for traits of importance for turf use,such as sward colour and overall quality, highlighted the great variation andthe occurrence of interesting accessions in all species. Other characters wererecorded, bearing specific importance in individual species, and in all casespromising accessions were identified. The germplasm of Festucarubra, Festuca arundinacea, and Loliumperenne proved highly infected by endophytic (symbiotic) fungi of thegenus Neotyphodium.     

Enhanced establishment and growth of giant cardon cactus in an eroded field in the Sonoran Desert using native legume trees as nurse plants aided by plant growth-promoting microorganisms and compost

To evaluate the feasibility of long-term desert reforestation technology of mixed vegetation, cardon cactus (Pachycereus pringlei) seedlings from indoor and outdoor nurseries were planted in the field adjacent to one seedling of potential legume nurse trees: mesquite amargo (Prosopis articulata), yellow palo verde (Parkinsonia microphylla), and blue palo verde (Parkinsonia florida). Some of the planting holes were also supplemented with common dairy compost. Additionally, the combinations of legume tree–cactus were inoculated with either a consortium of desert arbuscular mycorrhizal (AM) fungi, plant growth promoting bacteria (PGPB; the diazotroph Azospirillum brasilense Cd, and the phosphate solubilizer Paenibacillus sp.), or a mixture of all. The field experiments were evaluated periodically during 30 months for survival and growth. Cardons reared in an outdoor screen house survived better in the field than those reared in a controlled growth chamber and hardened later outdoors. Association with any legume nurse tree increased survival and enhanced growth of untreated cardons. For cardons growing alone, application of either compost, AM fungi, and all the treatments combined increased survival. For these plants, no treatment affected plant growth during the first 3 months after transplanting. Later, all treatments, except for AM fungi, enhanced plant growth. However, only 2 years after transplanting the enhanced growth effect of AM fungi was also significant. In the presence of the legume nurse trees, transient positive effects on cardon growth were recorded. General evaluation after 30 months of cultivation showed that the treatments positively affected cardon growth when growing alone or in combination only with mesquite amargo but not with the other two legume trees. This study proposes that young legume trees have the capacity to enhance survival and growth of cardon cactus, depending on the legume cactus combination. Additional treatments such as compost or PGPB can either amplify the effect or else attenuate it.     

Karyotypic and genome size variation in Cajanus cajan (L.) Millsp. (pigeonpea) and some wild relatives

Detailed karyotypes and 4C DNA amounts have been studied in five cultivars of Cajanus cajan and 20 species belonging to Cajanus, Rhynchosia, Dunbaria, Flemingia and Paracalyx. C. cajan shows intraspecific variability and its karyotype is most similar to that of C. cajanifolius (sect. Cajanus) in the morphology and number of satellite chromosomes and the lack of any correlation between chromosome size within the complement and asymmetry. Karyotypes of C. lineatus and C. sericeus belonging to sect. Atylia are similar with respect to maximum r-index and the ratio of longest and shortest chromosomes in their respective complements. C. acutifolius (sect. Frutocosa) is distinct in having a very low ratio (1.44) between the longest and the shortest chromosomes, while in C. albicans, C. goensis, C. scarabaeoides (sect. Cantharospermum) there is no chromosome pair with r-index >2.0. C. mollis and C. volubilis (sect. Volubilis) show similarity with regard to ratio between the longest and the shortest chromosomes and a distinct chromosome pair with an arm ratio of 2.7 and C. platycarpus is distinct (sect. Rhynchosoides) in having the smallest ratio (1.36) between the longest and the shortest chromosomes. 4C DNA amounts in Cajanus and Rhynchosia vary between 3.28 pg to 11.69 pg and 4.92 pg to 11.13 pg respectively, while in Dunbaria, Flemingia and Paracalyx these vary between 4.70 and 7:06 pg. In the genus Cajanus karyotypic features and 4C DNA amounts agree with the sectional classification and bring out a close relationship between C. cajan and C. cajanifolius. This is supported by studies based on seed protein patterns, isozyme analysis, trypsin and chymotrypsin inhibitor patterns, RFLP and RAPD data and crossability relationships. A clear relation between DNA amount and abnormalities effecting the extent of pairing and recombination in interspecific hybrids shows the importance of this study in developing future breeding programme involving C. cajan and its wild relatives that are of potential value.     

Effect of some fungicide seed treatments on the survival of Bradyrhizobium japonicum and on the nodulation and yield of soybean [Glycine max. (L) Merr.]

Several commercial fungicide seed treatments were evaluated for their possible effect on the survival of Bradyrhizobium japonicum on seeds and on the nodulation and yield of soybeans in a greenhouse and a field experiment. quinolate Pro (carbendazim and oxine copper), Vitavax 200FF (carboxin and thiram), and Monceren (pencycuron) had a small effect or no effect on the survival of B. japonicum and on the nodulation and yield of soybeans. They can thus be considered compatible with soybean seed inoculation. Germipro UFB (carbendazim and iprodione), Apron 35J (metalaxyl), and Tachigaren (hymexazol) decreased B. japonicum survival and the nodulation and yield of soybeans and thus cannot be considered compatible with soybean seed inoculation.     

Leaf position and genotype differences for mineral element concentrations in sorghum grown on tropical acid soil 1

Mineral element deficiencies and toxicities are common problems associated with sorghum [Sorghum bicolor (L.) Moench] production on acid soils. To better understand some of the mineral element problems and the analysis of plant tissue of sorghum plants grown on acid soils, four sorghum genotypes were grown on an acid Oxisol at Carimagua, Colombia limed with dolomite at 2 and 6 Mg ha^‐1.

Samples for mineral element analyses were obtained from leaves at different positions on the four genotypes. Concentrations of P and Mg were highest in the flag leaf (Leaf No. 1) and decreased as the position on the plant declined from the top of the plant for plants grown at 2 Mg lime ha^‐1. Similar decreases in P, Mg, K, and Zn concentrations occurred in plants grown with 6 Mg lime ha^‐1. Concentrations of Ca, S, Si, Mn, Fe, Cu, and Al increased as leaf position declined from the flag leaf for plants grown at 2 and 6 Mg lime ha^‐1. The higher lime supply enhanced Ca and reduced Mn and Fe concentrations in leaves. Differences in mineral element concentrations for the four genotypes used were fairly extensive. The elements to show the greatest range among genotypes were Al and Si and the elements to show the least range among genotypes were P, K, and S. Care should be used in collecting leaf samples for plant analysis and genotypic differences for accumulation of mineral elements should be considered in interpretation of results.