机械式空气整根钵苗移栽器的研究

空气整根钵苗全自动移栽机的核心部件是移栽器。采用机械方式完成全自动移栽机的送秧和投苗，简化了现有全自动钵苗移栽机的电动或气动送秧和投苗装置，降低了成本。移栽器的性能试验表明，所研制的移栽器性能良好，适应国内市场需要。     

南亚热带三种典型植被土壤动物对模拟N沉降增加的早期响应

A field-scale experiment arranged in a complete randomized block design with three N addition treatments including a control （no addition of N）, a low N （5 g m^-2 year^-1）, and a medium N （10 g m^-2 year^-1） was performed in each of the three typical forests, a pine （Pinus massoniana Lamb.） forest （PF）, a pine-broadleaf mixed forest （MF） and a mature monsoon evergreen broadleaf forest （MEBF）, of the Dinghushan Biosphere Reserve in subtropical China to study the response of soil fauna community to additions of N. Higher NH4^＋ and NO3^- concentrations and a lower soil pH occurred in the medium N treatment of MEBF, whereas the NO3^- concentration was the lowest in PF after the additions of N. The response of the density, group abundance and diversity index of soil fauna to addition of N varied with the forest type, and all these variables decreased with increasing N under MEBF but the trend was opposite under PF. The N treatments had no significant effects on these variables under MF. Compared with the control plots, the medium N treatment had significant negative effect on soil fauna under MEBF. The group abundance of soil fauna increased significantly with additions of higher N rates under PF. These results suggested that the response of soil fauna to N deposition varied with the forest type and N deposition rate, and soil N status is one of the important factors affecting the response of soil fauna to N deposition.     

磷酸铁盐涂层: 控制黄铁矿氧化的新手段

A novel coating technique was develped for controlling pyrite oxidation .The technique involved leaching pyrite particles with a solution containing low concentrations of phosphate and hydrogen peroxide.During the leaching rpocess,the iron released from pyrite by hydrogen proxide was precipitated by phosphate as a ferric phosphate coating .This coating was shown to be able to effectively prevent pyirte from oxidation and it could be established at the expense of only surface portions of pyrite.The emergence of this technique could provide a unique potential route for abating acid mine draingage and reclaiming sulfide-containing degraded mining land.     

On-line measurement of mercury in simulated flue gas

Total and elemental mercury (Hg) in simulated flue gas was measured on-line by a commercial Semtech^® Hg analyzer. This instrument is based on Zeeman modulated Atomic Absorption Spectrometry. Both a wet chemical solution and a dry physical pyrolysis converter were applied to reduce the Hg(II) in the gas before leading it to the detector. Results show that the Semtech^® analyzer is suitable for measuring elemental Hg even in the presence of 2500 ppm SO₂ and 500 ppm HCl. For the measurement of Hg(II), the wet method is suitable only at SO₂ concentrations <50 ppm. The dry thermal converter filled with crushed quartz chips together with a small amount of soda lime converts Hg(II) quantitatively at laboratory scale. This result is promising, since the trace gases delivered to the system, such as SO₂, and HCl are similar to those produced in coal burning and waste incineration processes. The limiting factor for such a converter is its comparatively short life time of performance, about 20 hours.     

庄浪县梯田化建设对生态-经济-社会协调发展的作用分析

应用对比、相关分析和效益分析，研究了坡耕地与梯田在保土、保水、保肥的差异，并对庄浪县梯田化建设对当地带来的生态、经济和社会效益进行量化计算，得出，梯田能促进水肥互相协调效应，供作物生长发育利用，增加粮食产出，达到高效用水、稳产高产的目的。结果表明随着庄浪县生态环境的改善和土地利用率的增加，当地生态、经济、社会效益取得显著提高，为庄浪农业产业化发展实施可持续农业发展战略奠定了基础，为实现全县生态、经济、社会的协调发展提供保障。     

典型黑土pH值变化对营养元素有效态含量的影响研究

采用室内培养实验的方法,控制典型黑土样品的酸碱度值,探讨典型黑土中Cu、Zn、Mn、P和Fe等营养元素有效态含量与pH值的关系。结果表明:pH值变化0.5个单位左右,有效态铜含量变化约0.5～1倍;有效态锰含量变化约3～5倍;有效态锌含量变化9～15倍之多;有效态磷含量变化约1.5～2倍;有效态铁含量变化约3～4倍。说明精确掌握土壤的酸碱度值对于土壤诊断、合理施肥、提高作物产量和实现土地的可持续利用都具有重要的理论与实践意义。     

丹江口水库水源区水土保持生态环境建设与发展对策

河南省淅川县是南水北调中线工程渠首所在地。全面地分析了该县水土流失的原因、危害。查找了水土保持工作存在的主要问题 ,并提出了淅川县今后水土保持生态环境建设与发展对策。     

The aqueous reduction of divalent mercury by sulfite

Divalent Hg is reduced by sulfite in aqueous solutions. The proposed mechanism involves the formation of an instable intermediate, HgSO₃, which decomposes to produce Hg⁺ which in turn is rapidly reduced to Hg⁰. The overall rate of the reaction is inversely dependent on the concentration of sulfite. This reaction may influence the concentration of Hg in cloud- and rain-water by reducing water soluble Hg²⁺ to volatile Hg⁰. At low concentrations of SO₂(g) (5 μg m⁻³, 25 °C), the rate of the conversion of Hg(SO₃)₂ ²⁻ to Hg⁰ becomes significant (> 1 % h⁻¹) at pH < 5.5. At higher S02 concentrations (500 pg m⁻³), the same rate is expected at pH < 4.5.     

施用生物炭对紫色土坡耕地耕层土壤水力学性质的影响

该研究通过野外坡耕地小区施用1%秸秆生物炭1年后的对比试验,揭示生物炭对川中丘陵区紫色土耕作层土壤水力学参数、大孔隙度及其对饱和导水率的贡献率所产生的影响。试验设对照区与施用生物炭区2个处理,各处理有3个平行小区,耕作层土壤分为表层和亚表层(2~7和7~12 cm)。比较2个处理小区试验结果,可以发现:1)施用生物炭导致植物难以利用的土壤滞留水和易流失的结构性孔隙水的含量(θstr)下降,而基质性孔隙中植物有效水含量显著提高(P0.05),由(0.058±0.003)cm3/cm3增加至(0.085±0.002)cm3/cm3;2)表层和亚表层土壤中对产流起主要贡献的半径125μm的总有效孔隙度分别平均增加54%和8%,其中孔径500μm的孔隙增加最为明显,高达110%和355%;3)表层和亚表层土壤的饱和导水率分别平均增加45%和35%。研究证明,施用生物炭,一方面,能增加土壤有效水的持水量,有利于植物抗旱;另一方面,提高土壤导水率,有利于水分入渗,从而减少地表径流及土壤侵蚀的发生。     

新形势下现代林业经营管理体系构建思考与探索

分析了以信息技术为支撑、以森林资源信息为核心的现代林业经营管理体系,指出了它以信息论、系统论、控制论、管理学理论、经济学理论、可持续发展理论、生态学理论为理论基础,并探讨了其独特的本质内涵和内在框架体系.