农田林网气象效应的研究

我国许多平原地区,自然灾害频繁,建立以农田防护林体系为骨架的农田生态系统,不仅是解决平原木材供应不足,而且是防灾治本,保障农业稳定发展的重要途径。因此,建设以农田防护林体系为中心的速生用材林基地,是当前许多国家在平原地区发展的共同趋势。我国平原面积约占国土总面积的27%,近90%的耕地分布在这些地区,可是长期以来,生态条件陷入恶性循环,农业生产低而不稳。它的原因是多方面的,但缺乏应有森林植被的     

我国平原农区复合农林业小气候效应研究概述

通过对近50年来我国平原农区复合农林业小气候效应总结，指出农田防护林及农林间作等复合农林业模式具有降低风速、调节气温和改善农田水分状况等小气候效应，为农业生产提供了重要的生态保障。     

试论泥炭的应用分类

泥炭是一种重要的肥料资源。近年来,全国各地普遍开展了挖掘泥炭,制造腐殖酸类肥料的群众运动。在实践过程中,这种泥炭腐殖酸类肥料在提高土壤肥力,增加作物产量等方面,显示了一定的效果。     

江苏省平原沙土区的水土流失与治理

江苏省平原沙土区水土流失面积5329km~2,主要分布在黄泛平原、盐城滨海平原、通南高沙土平原三个地区。水土流失导致这些地区的河道淤塞,排灌困难,农田日益减少,生态平衡遭到破坏。本文分析了平原沙土区水土流失的成因,提出了加快河沟破面植被和农田防护林网建设等治理建议。     

农田土壤与高产人参腐殖土壤的理化性状对比研究

为了改变伐林栽参的生产方式,实行“参农轮作”,以促进山区、半山区和平原地区农村参业生产的发展,并保护林业资源和生态平衡.我们通过农田土壤与高产人参腐殖土壤理化性状对比研究,找出两者的差异,以便用人工手段,将农田调控到高产人参所需的立地条件,并进行田间试验,为农田栽参提供科学依据.     

七姊妹山自然保护区泥炭藓湿地剖面特征及元素垂直分布规律

泥炭藓湿地是由适应能力强、耐周期性干旱的泥炭藓(Sphagnum)以及草本植物沼泽化形成的一种十分重要的湿地类型,也是一种重要的自然资源,多分布于湿润多雨的地区[1]。泥炭藓湿地在我国主要集中分布于松嫩平原、三江平原和若尔盖高原[2]。在亚热带山地,由于受水热条件的限制,泥炭藓湿地有小面积分布。2005年对湖北省七姊妹山国家级自然保护区的科学考察中发现了面积约300hm2的呈斑块状分布的亚热带亚高山泥炭藓湿地,其发现为鄂西山地古地质、古气候及植被变迁研究提供了珍贵的研究样本。目前国内外关于泥炭藓湿地的研究主要集中在湿地植被研究、泥炭元素分析、泥炭种子和孢粉构成分析、泥炭对古气候及古环境的反映、     

九江市水土保持区划及防治布局研究

水土保持区划是水土保持规划的基础和前提,是区域水土保持宏观管理和水土保持生态文明建设的重要依据。在江西省水土保持工作重要基础技术支撑成果《江西省水土保持区划及防治布局研究》确立的原则与方法基础上,将九江市划分为鄱阳湖丘岗平原农田防护水质维护区和幕阜山九岭山山地丘陵保土生态维护区2个三级区,又将鄱阳湖丘岗平原农田防护水质维护区划分为鄱阳湖丘岗平原水质维护区、鄱阳湖丘岗平原土壤保持区2个四级区,并基于水土保持功能提出了各分区的防治布局,为江西省首部设区市水土保持规划《九江市水土保持规划(2016—2030年)》的优质高效完成奠定了坚实基础,同时为九江市及其他区域的水土保持规划与宏观决策及加快推进生态文明建设提供了重要的指导与参考。     

太行山山前平原农田耗水影响因素与水分利用效率提高的途径

研究分析了太行山山前平原农田耗水的影响因素 ,并结合田间试验结果探讨了减少农田灌溉用水量 ,提高作物水分利用效率 ,实现地下水资源采补平衡的措施     

河北省平原农田防护林网增产节水效益评估

通过对现有资料分析,计算出河北省平原农田防护林网平均可使粮食作物增产14．9%、棉花4．6%，可减少农田水分蒸散16．0%。通过不同计算方法得出河北省平原农田防护林网有效控制表田面积为农田总面积的34．7%，从而得出河北省平原农田防护林网对农田的增产效益为11．09亿元／a，水文教益为2．86～3．27亿元／a, 总生态经济效益为13．95～14.36亿元/a。     

河北省平原农田防护林网增产节水效益评估

通过对现有资料分析，计算出河北省平原农田防护林网平均可使粮食作物增产１４．９％、棉花４．６％，可减少农田水分蒸散１６．０％。通过不同河北省平原农田防护林风在效控制农田面积为农田总面积的３４．７％，从而得出河北省平原农田防护林网对农田的增产效益为１１．０９亿元／ａ，水文效益为２．８６－３．２７％亿元／ａ，总生态经济效益为１３．９５％－１４．３６亿元／ａ。     

尕海湿地泥炭土土壤理化性质

泥炭是一种宝贵的自然资源,同时也是重要的生态资源,尕海湿地的泥炭土在涵养水源、储存碳汇方面有着举足轻重的作用。研究采用野外调查与室内分析相结合的方法,对尕海湿地泥炭土土壤的理化性质进行测定。结果表明:尕海湿地泥炭土的平均含水量为122.29%,说明尕海湿地具有较强的蓄水功能;土壤容重平均值为0.478 6g/kg,土壤总孔隙度平均值为78.186%。随着土层加深,土壤容重呈现出增大趋势,而总孔隙度呈现出降低趋势。(2)尕海湿地泥炭土的有机质、全氮、全磷、全钾平均含量依次为302.04,10.37,0.81,13.93g/kg,空间变异程度均属中等水平。随着土层加深,土壤有机质、全氮、全磷平均含量均呈现出下降的趋势,而土壤全钾平均含量呈现出先降低后升高的趋势,说明不同深度土壤中生物量的积累对土壤养分含量有重要影响。     

Microbial activity of peat soils of boggy larch forests and bogs in the permafrost zone of central Evenkia

The microbial activity of peat soils was studied in boggy larch forests and in an oligo-mesotrophic bog in the basins of the Kochechum and Nizhnaya Tunguska rivers (central Evenkia). It was found that the organic matter transformation in the peat soils of all the plots is mainly performed by oligotrophic bacteria composing 88–98% of the total bacterial complex. The major contribution to the organic matter destruction belonged to the heterotrophic microorganisms, the activity of which depended on the permafrost depth and the soil temperature, the soil acidity, and the botanical composition of the peat. Peat soils were characterized by different activities as judged from their microbiological and biochemical parameters. The functioning of microbial communities in the studied ecotopes of the permafrost zone was within the range of natural variations, which pointed to their ecological stability.     

长期不同施肥下红壤活性有机质与碳库管理指数变化

对长期不同施肥5a和10a后红壤活性有机质进行了测定，结果表明，耕作10a不施肥或仅施化肥（CK、N、NP、NK、PK、NPK）的土壤活性有机质（LOM）及碳库管理指数（CMI）都明显下降，最大下降（CK）分别为40．5％和48．1；而有机肥或有机肥化肥配合施用（M、MNPK、1．5MNPK），LOM和CMI则显著升高，最大升高（1．5MNPK）分别为183％和195；秸秆还田（SNPK）处理LOM和CMI先下降后增加，5a分别下降25．2％和31，10a又分别上升17．9％和13。说明化肥主要提高非活性有机质，有机肥则显著改善土壤有机质质量，秸秆还田对提高红壤有机质质量比有机肥慢。用33mmol L^-1、167mmol L^-1、333mmol L^-1KMnO4测定的三种活性有机质（本文分别称其为高活性有机质HLOM、中活性有机质MLOM和活性有机质LOM）的含量依次增加，分别占总有机质的5．6％、9．6％和14．5％。三种活性有机质之间呈显著或极显著相关，HLOM与MLOM相关系数为0．478^＊，HLOM与LOM为0．592^＊＊，MLOM与LOM为0．716^＊＊。作物产量只与MLOM和LOM极显著相关，相关系数分别为0．821^＊＊和0．602^＊＊，而和总有机质没有显著的相关性。同时，LOM及CMI与土壤阳离子交换量、交换性钾、交换性钙、盐基总量、微量元素等呈显著或极显著正相关，但总有机质与上述土壤化学指标相关性差。这些结果暗示LOM和CMI比总有机质更能客观反映土壤肥力和土壤质量的变化情况，应该成为描述土壤质量和评价土壤管理的良好指标。     

Nonspecific organic compounds in peat soils of the Subpolar Urals

Specific features of organic matter, molecular composition and distribution of oxygen-containing nonspecific organic compounds (fatty acids, long-chain aliphatic alcohols, and ketones) were revealed in two peat soils on slopes of the Subpolar Urals: the eutrophic peat soil of the spring mire (Hemic Histosols) and the peat soil of a slope mire (Fibric Histosols). Compounds that can serve as molecular markers for some evolutionary stages of peats were determined for this area. Based on the data obtained, the most probable causes of differences in the composition of organic compounds in the peats studied were found to be the following: environmental conditions, water and mineral regime of bog, and differences in the composition of peat-forming plants.     

有机肥和无机肥在提高黄潮土肥力中的作用研究

1981-1986年在黄潮土上的小麦-玉米肥料定位试验,对肥料用量、作物吸收量和土壤养分积累量的回归分析结果:化肥N和有机肥N有8.76%和42.54%进入土壤N库;化肥P和有机肥P有17.61%和17.20%进入土壤速效P库;化肥K和有机肥K有4.5%和2.3%进入土壤速效K库.化肥对土壤有机质含量略有增加趋势,有机肥对补给土壤P、K养分,改善土壤物理性状有明显效果.有机无机配合施用具有培肥、增产两方面的作用.     

New classification systems for tropical organic-rich deposits based on studies of the Tasek Bera Basin,Malaysia

Most schemes in common use for field and laboratory classification of peats were developed in boreal and humid temperate regions and do not recognize the distinctive features and specific uses of tropical peats, such as those of the Tasek Bera Basin in tropical Peninsular Malaysia. The important aspects of peat texture (morphology of constituents and their arrangement) and laboratory ash content (residue after ignition) need modification to be valuable for classifying these and other tropical peat deposits. In the Tasek Bera Basin, most of the deposits would not be considered as peat according to some classification schemes, even though most have C contents >25%. We propose a new three-group (fibric, hemic, sapric) field texture classification applicable to tropical organic deposits, which is similar to the system of the US Soil Taxonomy. The classification is based on the following factors: (1) visual examination of the morphology of the peat constituents (texture); and (2) estimates of fiber content and matrix (finest fraction of peat consisting of highly humified organic matter and inorganic material). The classification is applicable to all organic deposits with <65% ash (i.e., >35% loss on ignition). We also present a new laboratory classification of organic soils based on ash and C content. The US Soil Taxonomy classifies organic soils as having more than 12–18% organic C, depending on clay content. Ash content and these limits for organic soils allow the discrimination of four main groups: peat, muck, organic-rich soil/sediment and mineral soil/sediment. Peat is defined as having an ash content of 0–55%, muck 55–65%, organic-rich soil/sediment 65–80% and mineral soil/sediment 80–100%. The peat class is further subdivided into very low ash (0–5%), low ash (5–15%), medium ash (15–25%), high ash (25–40%) and very high ash (40–55%) subclasses.     

陕西武功县猕猴桃园土壤养分调查与评价

测定陕西武功县猕猴桃园土壤养分含量,评价土壤肥力状况,为指导果园科学施肥提供参考依据。本研究采集研究区10个代表性果园表层土壤样品,对其pH、有机质以及速效氮、磷、钾含量进行测定,结合相关分级标准,分析果园土壤肥力状况。结果表明:武功县猕猴桃园土壤pH在7.52～8.54,平均为8.16,属于弱碱性土壤;土壤有机质含量在10.78～26.73 g/kg,平均为18.43 g/kg,达到中量水平的土壤样品仅占25.1%,整体表现缺乏;土壤速效氮含量在47.60～254.16 mg/kg,平均为138.69 mg/kg,64.7%的土壤样品速效氮含量超过120 mg/kg,仅有8.0%的土壤样品速效氮含量缺乏;土壤有效磷含量在11.01～292.10 mg/kg,平均为59.22 mg/kg,达到丰富及以上水平的土壤样品占90.3%;土壤速效钾含量在32.81～458.20 mg/kg,平均为190.92 mg/kg,丰富、中量、缺乏的土壤样品分别占57.3%、28.2%、14.5%。研究区土壤pH、土壤有机质空间变异相对较小,土壤速效氮、磷、钾含量比较丰富,但空间分布不均衡。建议在今后土壤及施肥管理中,采取综合措施,适度降低土壤pH,以满足猕猴桃生长所需的土壤酸碱环境;加强有机肥的投入,逐年提高土壤有机质含量;控制氮、磷、钾化肥的施用,提高肥料利用率。     

改良剂对复垦土壤团聚体组成及有机碳含量的影响

为探究改良剂对复垦土壤团聚体组成及有机碳含量的影响,采用田间微区的方法按表层0—20 cm土壤重量占比1%,3%,5%的比例添加泥炭、腐殖酸和蛭石,研究3种改良剂对复垦土壤团聚体组成、总有机碳、各粒级团聚体有机碳含量、土壤红外光谱特征的影响。结果表明:施用3种改良剂后各处理土壤机械稳定性团聚体均以>5 mm的最多,施用泥炭和腐殖酸后>5 mm团聚体含量随着改良剂施用比例的升高而增大,且MWD(平均质量直径)值均高于CK。其中,5%腐殖酸对调控>5 mm团聚体含量效果最佳,在6个月时>5 mm机械稳定性团聚体占比达到60.03%。而施用蛭石后>5 mm机械稳定性团聚体的占比与CK相比有所下降。施用3种改良剂后土壤水稳性团聚体以<0.053 mm团聚体含量最高,但其含量均随改良剂施用比例的升高而降低。泥炭和腐殖酸能够提高复垦土壤总有机碳的含量,增强抗侵蚀能力和团聚体的稳定性,而施用蛭石后有机碳含量减少。泥碳、腐殖酸和蛭石各处理下各粒级机械稳定性团聚体有机碳含量均以>5 mm最高,0.053~0.25 mm次之,<0.053 mm最少,有机碳含量贡献率也以>5 mm团聚体的最大,泥炭和腐殖酸处理下>5 mm团聚体有机碳含量贡献率均高于50%,<0.053 mm团聚体有机碳贡献率仅有0.63%~2.82%。从土壤的红外光谱特征峰可以看出,施用腐殖酸能够增加土壤中的多糖类物质,而多糖类物质有大量的—OH,能与黏粒矿物晶面上的氧原子形成氢键而把土粒团聚起来。     

SOIL NUTRIENT CHANGES WITH FERTILIZER TYPE IN CASSAVA-BASED CROPPING SYSTEM

ABSTRACT

The changes in soil nutrient status following the application of different fertilizer types were studied in field experiments involving maize-melon intercrop relayed into a cassava-soybean intercrop between 1995 and 1997. The soil at the experimental site was a Kanhaplic Haplustalf, which was under continuous cultivation with arable crops for seven years and fallow for four years. The effects of organic and inorganic fertilizers were investigated singly and in combination. The type of fertilizer had no significant effect on the soil pH, although, cropping significantly lowered the pH from 6.0 to 5.7. Cropping also significantly reduced the soil organic matter and total nitrogen (N). The soil organic matter (OM) and total N were most depleted with organic fertilizer application. Complementary application of organic and inorganic fertilizers limited the degree of depletion from 31.0 to 12.1 g kg^?1 of OM and 1.8 to 0.6 g kg^?1 total N. Soil available P was increased (60%) by inorganic fertilizer while the organic fertilizer increased it by 145% and the combined fertilizer by 186%. Exchangeable calcium (Ca) was depleted by about 12% with organic fertilizer application, 15% by inorganic fertilizer and about 19% with complementary application of organic and inorganic fertilizers. Exchangeable sodium (Na) was reduced from 0.43 to about 0.38 cmol kg^?1 while magnesium (Mg) was increased from 0.5 to about 0.6 cmol kg^?1.     

Identification of primary substrates in organo‐mineral fertilizers by means of isoelectric focusing

Abstract

Organo‐mineral fertilizers (OMF) are used to improve the efficiency with which plants absorb the nutrients contained in mineral fertilizers, thanks to the properties of the fertilizer's organic component. The quality of the organic component, and hence its origin, is of primary importance for its efficient use in agriculture as a fertilizer. It is thus necessary to identify analytical techniques which are able to distinguish the primary substrates in a mixture, as well as their humification levels. In this study, isoelectric focusing was used to recognize the four primary substrates from different organo‐mineral fertilizers containing peat, leather meal, poultry manure, or dried pig slurry. The experiments gave positive results. Peat could be distinguished from leather meal, although poultry manure was not distinguishable from dried pig slurry.