抓住机遇,继往开来,再树“长治”新丰碑

１从战略全局高度,充分认识“长治”工程的重大意义长江流域人口占全国的１／３,粮食产量占全国的３６％,工农业总产值占全国的４０％,没有长江流域的稳定与发展,就没有全国的稳定与发展,长江中下游的洪灾是中华民族的心腹之患,上游不治理好,此患就难以消除。长江...     

Deficiency of N,P, K,Ca, Mg,or Fe Mineral Nutrients in Narcissus cv. “Garden Giant”

Narcissus cv. “Garden Giant” bulbs were grown in N, P, K, Ca, Mg, or Fe-deficient solutions and compared with bulbs grown in the control solution containing all these nutrients. Plants were sampled at 4 stages: (I) at planting, (II) at sprouting, (III) after flower senescence and/or after visible deficiency symptoms developed, and (IV) at lifting. Observation of visible deficiency symptoms showed that leaves of narcissus displayed chlorosis in the —N, —Mg, and —Fe treatments, while roots were most susceptible to Ca-deficient conditions. Root tips in the —Ca treatment showed brown in followed by root rot. In the —N treatment, shoot growth was markedly retarded and leaves were small and yellow. On the other hand, visible deficiency symptoms were not evident in the —P treatment except for early senescence. K deficiency symptoms were also not evident. Narcissus flowers were not affected by the mineral deficiencies and mineral contents in full-bloom flowers were not different between samples.

In the control plants, there was a large accumulation of N in the roots at sprouting and the content decreased thereafter. Large amounts of K accumulated in roots more than in any other organs. On the other hand the Ca content was high in the tunic and Ca in the scales was hardly mobilized thoughout the growth period. A large proportion of each element eventually accumulated in new inner scales whereas only a small fraction in the old outer scales. The -N, -Ca, and -Mg treatments severely depressed dry matter accumulation, unlike the -P, -K, and -Fe treatments. The -N treatment did not affect the concentration of other minerals, but the -P treatment tended to decrease N, K, Ca, and Mg concentrations. On the other hand, the -K treatment increased Ca and Mg concentrations. -Ca caused an increase in Mg concentration and -Mg raised Ca concentration. These results may be due to compensation effects of cation absorption for the maintenance of the cation/anion balance.     

Influence of trenching,soil amendments,and mulching on the mineral content,growth, yield,and quality of “Italian” prunes

Abstract

Yields were evaluated three years after applied treatments to determine if responses that were not evident during earlier years eventually occurred. Potassium sulfate was applied to established, non‐irrigated, K deficient trees on fine textured soil by banding, placing in augered holes, adding to the backfilled trenches, and by injecting into the soil. Trenches were dug in the fall beside trees to break roots and ammended during backfilling with K₂SO₄, dolomite lime or combinations of the two. Additional trees received a heavy compost mulch in the early fall. Trenching treatments were generally detrimental. Trenching alone reduced yield and leaf Ca but increased fruit soluble solids content. Trenching plus K₂SO₄, trenching and lime, all soil amendments, and mushroom compost elevated leaf K from deficient or below normal to the normal range, but decreased leaf Mg. Most K application techniques eventually increased yield, but simple surface applications of K₂SO₄ in a narrow band were as effective as other more costly procedures. Mulching treatments appear to be as effective as K additions and produce quicker yield responses. Mushroom composts and alfalfa increased leaf N and yield in two years. Mushroom compost doubled yield even three years after a single application.     

承载梦想,与“三农”同行

<正>年初改版,我们只是想办一本农业农村方面的综合性外刊,搭建一个交流思想、凝聚智慧的平台,告诉你农业农村农民与这个社会、这个世界的关系。而走过这一年,我们发现,我们所收获的远不止杂志本身。我们在感受这个伟大时代的深刻变革,在感受柔弱"三农"的茁壮成长,在感受那些忧国忧农的情     

重视农业“安全质量”,加强农业“清洁生产”

文章强调了农业生产的安全质量问题 ,并在分析了安全生产的必要性的基础上 ,提出了加强清洁生产的见解。     

River and harbor remediation: “polluter pays,” alternative finance,and the promise of a “circular economy”

Journal of Soils and Sediments - Contaminated sediments in rivers, lakes, and harbors around the world result in diminished ecological health, degradation of environmental resources, economic...     

水土保持“放管服”咨询,水利部专家答疑

<正>1 咨询内容一《水利部关于进一步深化"放管服"改革全面加强水土保持监管的意见》(水保[2019]160号)第三条(二)款"强化监测和监理"明确:编制水土保持方案报告书的项目,应当依法开展水土保持监测工作。而以前的要求是动用土石方达到一定数量才开展监测,现在只要编制水土保持方案报告书的项目都应该开展监测吗?如果工程已完工,水土保持方案报告书是补报的,监测工作还需要开展吗?专家答复:问题一:按照《水利部关于进一步深化"放管服"     

环境危机,“继续生存还是自我毁灭”

世界范围暴发的禽流感疫情愈来愈受到全世界的关注，人们的健康可能会受到极大威胁，各国政府及时有力的措施，目前已经使禽类疫情得到了很大程度的控制，所有与之相关的科研和预防工作都在积极主动地进行着，与之对比，在2003年SARS出现的时候，曾一度引起恐慌。可以设想，如果疫情没有受控，那么人类的生存安全将面临一场怎样的挑战。从更高层次的意义上来说．病毒的传播变异、疫情的扩散是人类的生存环境发生了变化而威胁到了人类的生存和发展，因而是—个环境安全问题。     

水土保持“放管服”咨询,水利部专家答疑

《水利部关于进一步深化"放管服"改革全面加强水土保持监管的意见》(水保[2019]160号)自2019年5月印发实施以来,对于强化水土保持监管意义重大,本刊2020年第7期、第8期已刊发了部分业界对文件中相关条款的疑问及水利部专家的答复,本期继续整理刊发,以飨读者。     

水土保持“放管服”咨询,水利部专家答疑

<正>8 咨询内容八一些开发区、工业园区之前编制过开发区或园区基础设施水土保持方案,并得到了批复。请问:这类开发区或园区基础设施水土保持方案,属水利部水保[2019]160号文中的"水土保持区域评估报告"吗?专家答复:根据国务院要求精神,《水利部关于进一步深化"放管服"改革全面加强水土保持监管的意见》(水保[2019]160号)明确,在各类开发区推行水土保持区域评估。您提到的开发区或工业园区基础设施水土保持方案和该文件中的水土保     

水土保持“放管服”咨询,水利部专家答疑

《水利部关于进一步深化"放管服"改革全面加强水土保持监管的意见》(水保[2019]160号)自2019年5月印发实施以来,对于强化水土保持监管意义重大,本刊2020年第7期、第8期、第11期已刊发了部分业界对文件中相关条款的疑问及水利部专家的答复,本期继续整理刊发,以飨读者。     

Effect of Molybdenum Foliar Sprays on Yield,Berry Size,Seed Formation,and Petiolar Nutrient Composition of “Merlot” Grapevines

Abstract

Field experiments with irrigated “Merlot” vines were carried out at 3 sites in the Mount Lofty Ranges of South Australia over 3 years to examine the effects of molybdenum (Mo) foliar sprays on bunch yield, berry size, and nutrient composition of petioles. Bunches were divided into different size grades for black and green berries. Basal petioles were sampled at flowering and veraison for nutrient analyses. In year 3, seed number per berry was assessed at sites 2 and 3. Two Mo foliar sprays (each spray contained 118 g Mo as sodium molybdate/ha in 410–800 L/ha of water) applied before flowering increased yield per vine and bunch weight in all experiments in year 2 and at site 3 in year 3. Yield responses ranged from 221% at site 1 to 750% at site 2 in year 2 and 70% for site 3, year 3. Average bunch weight increased from 243% at site 2 to 425% at site 1 for year 2 and by 69% at site 3 in year 3, and was the main yield component affected by Mo application. In year 1, the application of Mo did not affect yield or bunch weight at any site. In year 2, the application of Mo increased the yield of 5–15 mm colored berries by 301, 499, and 258% at sites 1, 2, and 3, respectively, and by 70% at site 3, year 3. Mo application increased the percent of berries, which had one or more functional seeds (when assessed at sites 2 and 3 in year 3). Molybdenum concentrations in petioles sampled at flowering and veraison increased in response to applied Mo in all years. Petiolar Mo concentrations in unsprayed vines were consistently higher in year 1 compared with other years. The effect of applied Mo on the concentration of other nutrients in basal petioles sampled at flowering and veraison were small and of little practical importance. Nitrate-N did not accumulate in the petioles of unsprayed plants in any year. Changes in petiolar Mo concentrations between flowering and veraison were dependent on supply. Nitrate-N, total-N, and phosphorus (P) concentrations declined with time, while calcium (Ca), manganese (Mn), and iron (Fe) tended to increase. At flowering, Mo concentrations in basal petioles of 0.05–0.09 mg/kg were associated with significant bunch yield response to applied Mo. Molybdenum deficiency can be a major factor in the occurrence of berry development disorders such as shot berry formation and hens and chickens (millerandage) in “Merlot” grapevines. The increased percent of colored berries with one or more functional seeds and the decrease in the proportion of green berries suggests that Mo application affected pollination and/or fertilization, and thereafter berry development.     

雨前“茅山青峰”,“雨花”茶开采期预报方法

本文以常年种植的茶树群体品种为对象,着重讨论了茅山丘陵地区1971～1985年春茶开采与气象因素之间的关系,建立了温湿、低温冻害隶属函数和春茶开采预报方程。据预报方程进行历史拟合和预报,则理论值与实际开采日期的误差为±2天,为指导春茶的适时采摘提供理论依据。     

“Laterite profiles” and “lateritic ironstones” on the hawkesbury sandstone,Australia

Laterite profiles in the Sydney area are generally regarded as fossil soils, formed during the Miocene, on a peneplain, under a tropical climate. It is also held that subsequent uplift and dissection destroyed much of this surface together with the laterite profiles. These views are poorly established yet widely accepted. This study demonstrates that there is a very close mineralogic and stratigraphic relationship between the “laterite profiles” and the Triassic Hawkesbury Sandstone, such that the profiles are best regarded as iron rich sandstone units undergoing contemporary near-surface alteration including the mobilization of iron minerals as crystalline solids.     

“花而不实”油菜体内硼与氮,钾,镁和钙关系的研究

通过田间调查结合室内分析，研究了缺硼油菜体内硼的含量以及硼与氮、钾、镁、钙含量的关系，结果表明缺硼油菜器官的Ｎ／Ｂ比高于正常油菜，缺硼后钙、镁含量增加而钾含量下降，缺硼使油菜叶片含糖量增加，而角果枝中含糖量下降。