Sensitivity analysis of optimal operation of irrigation supply systems with water quality considerations

A model for optimal operation of water supply/irrigation systems of various water quality sources, with treatment plants, multiple water quality conservative factors, and dilution junctions is presented. The objective function includes water cost at the sources, water conveyance costs which account for the hydraulics of the network indirectly, water treatment cost, and yield reduction costs of irrigated crops due to irrigation with poor quality water. The model can be used for systems with supply by canals as well as pipes, which serve both drinking water demands of urban/rural consumers and field irrigation requirements. The general nonlinear optimization problem has been simplified by decomposing it to a problem with linear constraints and nonlinear objective function. This problem is solved using the projected gradient method. The method is demonstrated for a regional water supply system in southern Israel that contains 39 pipes, 37 nodes, 11 sources, 10 agricultural consumers, and 4 domestic consumers. The optimal operation solution is described by discharge and salinity values for all pipes of the network. Sensitivity of the optimal solution to changes in the parameters is examined. The solution was found to be sensitive to the upper limit on drinking water quality, with total cost being reduced by 5% as the upper limit increases from 260 to 600 mg Cl l^–1. The effect of income from unit crop yield is more pronounced. An increase of income by a factor of 20 results in an increase of the total cost by a factor of 3, thus encouraging more use of fresh water as long as the marginal cost of water supply is smaller than the marginal decrease in yield loss. The effect of conveyance cost becomes more pronounced as its cost increases. An increase by a factor of 100 results in an increase of the total cost by about 14%. The network studied has a long pipe that connects two distinct parts of the network and permits the supply of fresh water from one part to the other. Increasing the maximum permitted discharge in this pipe from 0 to 200 m³ h^–1 reduces the total cost by 11%. Increasing the maximum discharge at one of the sources from 90 to 300 m³ h^–1 reduces the total cost by about 8%.     

基于正交实验的两种苦苣苔叶片扦插繁殖研究

以苦苣苔品种Primulina dryas‘Hisako’和Primulina‘Blue Mood’为试材,采用正交实验设计,分析不同因素、不同基质组分对扦插成活率、子株数、子株叶数的影响,并筛选出最优组合。探讨影响报春苣苔属扦插成活的因素,为报春苣苔属的扦插繁殖技术提供参考依据。结果表明:3种不同因素对Primulina dryas‘Hisako’成活率的影响大小为浓度>基质>叶片部位,对子株数的影响大小为叶片部位>浓度>基质,对子株叶数的影响大小为基质>叶片部位>浓度,最优组合为IBA+NAA等量混合浓度100 mg·L^-1+泥炭:珍珠岩:蛭石的体积比2∶1∶1+叶片下部。4种基质组分对P.‘Blue Mood’成活率的影响大小为泥炭>稻壳炭>蛭石>珍珠岩,对子株数的影响大小为珍珠岩>泥炭>蛭石>稻壳炭,对子株叶数的影响大小为泥炭>稻壳炭>珍珠岩>蛭石,扦插基质最优组合为泥炭、珍珠岩、蛭石、稻壳炭的体积比6∶2∶2∶1。     

生物炭浸提液对小白菜种子萌发及幼苗荧光作用的影响

生物炭被广泛应用于低产地改良以及重金属污染土壤修复,但是其应用可能对植物存在潜在毒性。为了揭示生物炭的潜在植物毒性,用不同来源、不同浓度生物炭浸提液对小白菜种子进行处理,检测种子萌发以及幼苗生长相关指标。结果显示,酒糟生物炭和梨木生物炭浸提液对小白菜种子萌发以及幼苗生长具有明显作用,但不同生物炭浸提液以及不同浓度浸提液影响差异较大。①酒糟生物炭和梨木生物炭浸提液原液均显著降低小白菜种子萌发(P<0.05),但稀释后的浸提液却促进小白菜种子萌发,尤其是稀释50倍后梨木炭浸提液和酒糟炭浸提液处理的小白菜种子萌发率分别比对照高16.67%和8.33%;②生物炭浸提液可提高小白菜幼苗株高和根系活力,尤其浸提液原液处理的植株株高、根系活力显著高于对照(P<0.05);酒糟生物炭浸提液的促进作用明显低于梨木生物炭;③生物炭浸提液均可提高小白菜幼苗叶片叶绿素含量、光化学效率（Fv/Fm）、实际量子产量（ΦPSⅡ）和表观光电子传递速率（ETR）等,且供试植株幼苗叶片叶绿素含量、Fv/Fm、ΦPSⅡ、ETR等随生物炭浸提液浓度增加而增加;但酒糟浸提液对小白菜幼苗叶片荧光作用的影响低于梨木生物炭浸提液;④生物炭浸提液能显著降低幼苗丙二醛含量 (P<0.05),且其随生物炭浸提液浓度增加而降低。由此表明,酒糟生物炭和梨木生物炭浸提稀释液均可提高小白菜种子萌发率及幼苗根系活力,增强幼苗叶片的荧光作用,但酒糟生物炭浸提液的影响作用低于梨木生物炭。     

尾巨桉引种新区连续年龄序列生长量及土壤理化特性

为探明尾巨桉引种新区林木生长量及土壤理化特性,在桂西北乐里林区设置尾巨桉连续年龄序列观测样地,对林分胸径、树高、蓄积量及其土壤理化性质进行测定。结果如下:1)1～4a生尾巨桉胸径平均总生长依次为5.0,8.0,9.7和10.7cm;树高平均总生长依次5.1,8.8,11.2和12.1m;林分平均总蓄积依次为8.29,31.76,51.45和71.89m3/hm2。2)林地(0～100cm)土壤容重为1.188～1.498g/cm3,总孔隙度为46.79%～59.90%,其中非毛管孔隙度为10.34%～28.50%。3)土壤pH值为5.44～5.60;有机质含量为0.78%～2.51%;全N和全P含量分别为0.04%～0.11%;全K含量为0.40%～0.50%;速效K(42.7～63.5mg/kg)>有效Mn(5.91～22.59mg/kg)>速效P(1.4～6.8mg/kg)>有效Zn(0.61～1.72mg/kg)>有效B(0.07～0.35mg/kg)。研究结果表明,桂西北乐里林区尾巨桉引种新区林地土壤容重较大,土壤主要养分含量普遍缺乏,林木生长量较低。     

Epidemiological investigations of an outbreak of intestinal atresia in two Israeli dairy herds

An epidemiological investigation of an outbreak of intestinal atresia in Israeli Holstein-Friesian newborn calves showed a linkage with rectal palpation for early pregnancy diagnosis, performed less than 42 days after insemination. The odds of an exposed calf, i.e., one born to a dam that was diagnosed by early palpation as having intestinal atresia were 119.7 times higher than one born in normal control herds (95% CI; 7.4-1946.3). A total of 682 calves-at-risk was recorded from mid-1998 to mid-2000 and a total of 47 calves (6.9%) were born with intestinal atresia during this period. Two forms of intestinal atresia were recognized at post-mortem: atresia coli and atresia ilei.     

紫外分光光度法测定沙拉沙星可溶性粉的含量

为了快捷简便地控制沙拉沙星可溶性粉生产过程中沙拉沙星的含量，采用紫外分分光光度法测定沙拉沙星的含量，平均回收率为99．9％，RSD=0．33％，与高效液相色谱法比较结果基本一致。     

Phenotypic and genotypic analysis of a commercial cultivar and wild populations of Anemone coronaria

Seven wild populations of Anemonecoronaria were assessed for 11 phenotypic traits, most of them having economic value for the flower industry. The wild populations were sampled to represent the diversity in habitats, climates, rock and soil types, terrains, and elevations in Israel. AFLP analysis was carried out on 12 individuals from each of six out of the seven wild populations and for six individuals from the commercial cultivar ‘Mona-Lisa’. It was found that the Dorot population, which is located in the area bordering the semi-arid zone at the very end of the species distribution, exhibits extreme and different phenotypes with relatively low variability compared withthe other wild populations. The other six wild populations, that grow in more favorable geographic and climatic conditions exhibit phenotypes with larger plants, larger numbers of flowers and less dissected leaves. These populations were less uniform than that of Dorot. Genetic characterization by AFLP markers revealed a total of 165 bands. The wild populations exhibit wide variation within-population, with about 80% polymorphic bands and average gene diversity between pairs of about 30%. The Dorot population has the lowest genetic variation and the Megido population the highest. Thus, the phenotypic variation reflects the genetic variation. The cultivar ‘Mona-Lisa’, as expected, has much lower genetic variation. The Dorot population and the ‘Mona-Lisa’ cultivar were found to have the largest genetic distances from the other wild populations, and the highest genetic variation between themselves. Phenetic analysis yielded a dendrogram describing the genetic relatedness of these populations. This revised version was published online in August 2006 with corrections to the Cover Date.     

Cultivar identification and genetic map of mango (Mangifera indica)

Amplified Fragment Length Polymorphism (AFLP) information was used for identification of mango (Mangifera indica L.) cultivars, for studying the genetic relationship among 16 mango cultivars and seven mango rootstocks and for the construction of a genetic linkage map. Six AFLP primer combinations produced 204 clear bands and on the average 34 bands for each combination. The average Band-Sharing between cultivars and rootstocks was 83% and 80%, respectively. The average Band-Sharing for mango is 81%. The probability of obtaining a similar pattern for two different mango cultivars and rootstocks is 6 × 10⁻³and 2 × 10⁻³, respectively. A preliminary genetic linkage map of the mango genome was constructed, based on the progeny of a cross between ‘Keitt’ and ‘Tommy-Atkins’. This linkage map consists of 13 linkage groups and covers 161.5 cm defined by 34 AFLP markers. This revised version was published online in August 2006 with corrections to the Cover Date.     

Laboratory studies on pteridophyte breakdown by a soil mite

Twenty six species of pteridophytes (ferns and fern allies) were offered to the soil mite Rhizoglyphus robini Claparède (Acari: Astigmata: Acaridae) in Petri dishes. All plants provided nutrients and promoted growth of mite populations. Leaves of sixteen (61.5%) species were totally consumed or skeletonized while green, another seven only upon browning. The remaining three were left intact even after 3 months, although sori and their leachates provided food for the mites. Paper impregnated with pteridophyte leachates was consumed and encouraged mite reproduction. These findings neither support nor oppose the view that pteridophytes are under-utilized by arthropods but the adaptability of the specific experimental organism might have affected the results. Invertebrates feeding on dead, decomposing pteridophytes possibly reduce the latters' allelopathy to other plants. The ability of Rhizoglyphus to subsist on plant leachates, as well as bacteria or fungi developing thereon, could explain the mode of survival of this and other soil arthropods in deep, mineral soil strata.