Joint ventures in private forestry in Ireland

A study was conducted with the objective of obtaining a profile of farmers who have participated in the Farm Partnership Scheme in Ireland. This scheme is a joint venture between Coillte (The Irish Forestry Board) and farmers. Under the terms of the scheme, Coillte is responsible for the establishment, management and harvesting of the forest plantation on the farmer’s land. The farmer retains ownership of the land, receives premium payments and shares in the harvesting profits. Fifty farmers who joined the Farm Partnership Scheme between 1993–1997 were interviewed in 1999 and a detailed questionnaire was completed. Survey results indicate that the typical farm partner was male, married and aged 50 years or older. Over half of those surveyed had an off-farm job. The most popular reason for farmers opting to participate in the Farm Partnership Scheme was that they did not have sufficient time to undertake the establishment and management of a forest plantation themselves. The average size of forest established under the scheme was 23.7 ha, with Sitka spruce the most popular species planted. The average annual payment under the scheme was €8077. For 46% of those surveyed, the returns from the Farm Partnership Scheme comprised all of their farm income.     

谈如何抓好公路路面工程管理与质量管理

认真执行操作规程,实施规范化、制度化的质量管理。建立完善的质量保证体系,并且强化质量检测手段,要把施工管理重点放到第一线,特别是抓好工序管理,坚持质量检查制度,增强职工的质量意识。     

保健植物在广州市居住区的应用研究

文章通过对广州市不同年代建设的9个居住区进行调查研究,对常见保健植物的种类和功能进行分析与归纳,结果表明,广州居住区保健植物的树种虽然较多,共记录有55科80种,但能广泛应用的树种较少,常用的只有33科50种。在保健功能应用上,树种多以观赏型、芳香型、环保型植物为主,而听觉型、触觉型和抑菌释氧类的保健植物应用较少,建议加强科普宣传,增加这些保健植物在居住区绿地中的应用,为保健植物在城市居住区的应用提供思路和理论依据。     

成都市城郊水产品中有机氯的安全评价

为了查明成都市城郊水产品中有机氯的安全性,在成都市三环路附近的7个鱼塘采样,采用微波萃取-气相色谱法对样品进行有机氯农药(HCHs和DDTs)含量测定,探讨其来源,并对鱼进行安全性评价.研究结果表明:个别鱼塘中水和底泥有机氯农药含量超标,鱼体内有机氯农药均未超过国家食用卫生标准.相对高值出现在西北部,相对低值出现在南部.同一地点不同鱼类体内有机氯含量比较,草食性鱼类＜杂食性鱼类＜肉食性鱼类.依据不同异构体的含量及分布,可以初步判断近年锦江区有新的HCHs污染源输入,其他点有新的DDTs污染源输入.同一鱼塘中,有机氯农药的含量总体为水<鱼<底泥.     

Epichlorohydrin and aspartic acid incorporated into sawdust and application as sorbent for methylene blue

In this paper, a new cation exchanger is prepared by activating sawdust with epichlorohydrin, followed by coupling the epoxy-activated sawdust with aspartic acid. The sawdust cation exchanger (SCE) was investigated for its methylene blue (MB) removal capacity from aqueous solution. The removal experiments were performed under various conditions such as different initial pH, SCE dosage, dye concentration, ionic strength, and contact time in a batch system. The highest sorption capacity of MB was obtained beyond pH 4. The 2.0 g/l or more of SCE could remove above 95% of MB from 250 mg/l of dye solution. Increasing the ionic strength of the solution caused decline of MB sorption. The sorption isotherm conformed well to the Langmuir model. The sorption process could be described by the pseudo-second-order kinetic model.     

土壤科学与社会发展简论

指出了土壤在农业生产中起着基础性的作用,土壤科学的发展在人类社会的发展中也起到了重要的作用,它提供给人类生存居所及粮食物品,同时对人类所生存的生态环境条件起到了保障性的作用。就当前土壤科学与社会发展最为密切的三个领域展开了论述,指出了在社会的发展过程中,土壤科学的地位与作用越来越不容忽视,在经济社会发展的过程中,土壤科学的重要性应当进一步引起我们的重视,因为在经济发展过程中对土壤环境的破坏必然会阻碍经济社会的进一步发展,所以我们必须合理利用土壤资源,并不断推动现代土壤科学对社会发展的有益影响。     

介绍一种带电磁过滤装置的机油专用滤油机

带电磁过滤装置的机油专用滤油机是利用电磁线圈产生的直流磁场,作用于具有较大导磁系数物,从机油中除去铁、铜等金属氧化物及其他杂质的一种装置。机油中的铁、铜等金属会被带磁的多层不锈钢网吸附住,达到过滤的作用。本文介绍了一种能对机油中含有的铁、铜等金属进行有效分离的滤油机。     

黄芪栽培技术

黄芪是著名的滋补中药材。通过对其形态特征、生态习性、栽培技术、采收与加工及病虫害防治的描述,表明我省的黄芪是畅销国内外市场的重要优质地道药材。指出了野生黄芪资源逐年减少,人工栽培潜力巨大,各地可建立固定的人工繁殖基地,解决民有林以短养长问题。     

大兴安岭林区沼泽-森林人工造林效果综合评估

采用样带网格调查方法,研究大兴安岭22年生人工兴安落叶松沼泽林的群落结构、蓄积量、植物多样性及其沿沼泽-森林过渡带水分环境梯度的变化规律,并与天然沼泽森林进行对比分析,结合经济效益及环境影响,对沼泽-森林人工造林效果进行综合评估,提出沼泽-森林的分类经营模式.结果表明:1)天然沼泽林群落建群种沿沼泽-森林过渡带环境梯度发生明显的更替,而人工落叶松沼泽林均以落叶松为优势种;天然沼泽林的垂直结构比人工落叶松沼泽林完整;2)人工落叶松沼泽林的蓄积量沿着沼泽到森林方向的环境梯度呈增加趋势(4.3497～6.990 5 m3·hm-2a-1),而天然沼泽林呈减少趋势(6.689 8～1.411 8 m3·hm-2a-1);3)人工落叶松沼泽林的物种丰富度指数较相应生境地段天然沼泽林提高9～25种,而其Shannon-Wiener多样性指数和Jsw均匀度指数却较天然沼泽林下降了0.221 4～0.858 2和0.234 3～0.404 2;4)人工落叶松沼泽林的地下水位和泥炭层厚度较天然沼泽林有所下降(分别下降15.5～36.1 cm和9.6～25.2 cm);5)在沼泽-森林过渡带内培育落叶松人工林可获得较高经济效益(投入产出比为1:2.4～1:9.6);6)沼泽森林的分类经营模式为:典型草本沼泽生境应保持原始状态,沼泽-森林过渡带的中下部生境应培育毛赤杨沼泽林,过渡带的中上部生境可以培育人工落叶松沼泽林.