节能型露地营养液栽培装置

本文介绍一种便于在发展中国家和落后地区推广应用的营养液栽培装置。本装置设在露地，不用电，不需进行营养液管理（在栽培过程中不需分析营养液的营养成分和校正ｐＨ值等），可以在如下恶劣的环境中推广应用：（１）不能供电的地区，如远离陆地的海岛等；（２）严重干旱地区；（３）沙漠或荒漠化地区；（４）土壤中盐类聚积很多的盐碱地区；（５）土壤酸化严重的地区。     

开发营养液栽培系统生产高糖度番茄

采用根区限制型营养液栽培装置，可周年进行高糖度番茄的密植栽培。一年栽培３．５－４茬，年产量达１０－１５吨／０．１公顷，糖度为８－１０％。     

营养液栽培中杀菌装置的开发

在营养液栽培中，由于营养液污染而导致栽培植物发生根腐病已成为严重问题。作者利用紫外线灯安装了一套紫外线杀菌装置。当循环的营养液经该装置时，其中的病原菌被杀死。作者还研制了一种陶恣过滤器，通过该过滤器不但能将营养液中的污染物除去，提高营养液的透明度，而且该过滤器还有吸附细菌的作用，使营养液中病原菌的数量大为减少。     

设施栽培中营养液成分的在线检测

设施栽培中为了加强营养液的管理并循环使用营养液,需在线检测营养液的EC值、pH值和各种养分的含量,及时调配营养液以达到养分均衡。本文利用离子选择性电极实现了对氮、钾、钙等离子浓度以及EC值和pH值的在线检测,并根据各营养元素浓度在特定作物特定生长期及生长环境相对稳定的一段时期内与EC值、pH值之间相对稳定的关系,以及各营养元素之间变化关系实现了磷、硫和镁离子浓度的软测量。     

营养液栽培番茄青枯病防除法

笔者探讨了营养液栽培番茄青枯病防除法，结果表明，可通过防止原菌带人现场，增减液６０℃５分钟加热消毒，ＰＨ控制在５．０以下，ＥＣ３．０ｍＳ／ｃｍ以下；地发病现场在栽培结束时用氯剂进行消毒等能有效地防止番茄青枯病的发生。     

中国水土流失现状与动态变化

利用第三次水土流失普查数据,分析了目前我国水土流失总体状况和水蚀、风蚀、冻融侵蚀状况以及东部、中部、西部和东北地区4个经济区域水土流失状况。结合水利部开展的第一、二次全国水土流失普查数据,分析了15年来我国水土流失的动态变化情况和主要河流多年来土壤流失变化状况。研究表明,不论是山区、丘陵区、风沙区还是农村、城市、沿海地区都程度不同地存在着水土流失,水蚀严重地区主要集中于黄河中游地区的山西、陕西、甘肃、内蒙古、宁夏和长江上游的四川、重庆、贵州、云南,风蚀严重地区主要集中在西部地区,我国水土流失总面积在减少,强度在下降。     

青海三江源区土壤侵蚀现状及其分布

通过对青海长江、黄河和澜沧江三江源区2005年时像的土壤侵蚀遥感调查,从宏观上查清了该区土壤侵蚀类型、面积和分布:三江源区土壤侵蚀面积11.48万km2,其中水力侵蚀1.84万km2,风力侵蚀1.16万km2,冻融侵蚀8.48万km2。土壤侵蚀主要分布在果洛州6县、玉树州6县、海南州2县、黄南州2县和格尔木市1乡,共涉及16县1乡。三江源区水力侵蚀主要发生在5—9月份,风力侵蚀主要发生在冬春季节,冻融侵蚀主要发生在4—5月份。该项研究为三江源区生态环境保护和建设的决策、规划及研究提供了基础数据。     

昆山市土壤养分现状与变化趋势研究

2009年对昆山市土壤养分进行检测,检测结果显示：有机质35.5 g·kg-1,全氮2.22 g·kg-1,碱解氮162 mg·kg-1,有效磷15.1 mg·kg-1,速效钾115 mg·kg-1,pH值6.0。与第二次土壤普查相比,有机质和全氮含量呈上升趋势,碱解氮、有效磷、速效钾含量明显提高,pH值呈下降趋势。     

基于面向对象影像分类技术的生态清洁小流域现状调查

结合当前北京市开展的生态清洁小流域建设,尝试利用现有的高分辨率航片,采用基于面向对象的高分辨率影像分类技术和G IS技术来开展生态清洁小流域水土保持现状等本底资料的调查,从而为生态清洁小流域的基础数据库建设、治理措施规划与布局提供基础数据和科学依据。应用实例表明,采用面向对象影像分类技术开展生态清洁小流域现状调查,在方法上、技术上都是可行的,不仅可以提高调查的客观性、准确性和现势性,而且也可以大大提高调查的工作效率,是未来生态清洁小流域调查的可选方法。     

Effect of Integrated Nutrition in Aromatic Rice on Carbon and Nutrient Status in an Inceptisol

Inorganic fertilizer-based nutrient management is the maintenance of soil fertility for sustaining increased crop productivity, but often at the cost of degrading soil health. This study was conducted to determine whether incorporation of organics in the conventional inorganic-based nutrient management practice on aromatic rice could sustain both fertility and soil organic carbon status on a silt loam Aeric Haplaquept. Addition of organic manure along with inorganic fertilizer could almost maintain organic carbon status of soil, while the treatment only with inorganic fertilizer registered a substantial decrease (6.58%) from its initial value. Among the treatment combinations, the treatment receiving 1 t ha^?1 mustard cake and inorganic fertilizer @ N₄₀P₂₀K₂₀ was the best, which registered the highest grain (3.01 t ha^?1) and straw (5.32 t ha^?1) yield of rice, highest nutrient uptake, and least decline in available N, P, and K status of soil. However, even the best treatment combination also was proved to be suboptimal in sustaining soil fertility.     

中国西南地区农业机械化现状及发展战略

中国西南地区农业机械化水平在全国最低，原因在于其不利的地理条件、落后的经济状况及大量的农村人口。提出了在新的环境条件下改善这一状况应采取的措施：利用中国加入WTO的机遇，因地制宜，采用正确的发展战略，合理地选择农业机械、机械化技术及机械化环节，借鉴外国与国内其它地区的经验，集成有关的技术、措施和政策，在机械化技术、农业机械的管理和推广、服务体系建设以及相关的措施、政策等方面实施创新，通过农业产业化、信息技术、适用技术发展农业机械化，加强研究开发工作，加强农村基础设施建设。此外，还需要一套全国性的法规政策体系来促进农业机械化工作。     

Mineralogy and Fertility Status of Selected Soils of the Eastern Cape Province,South Africa

Abstract

Thorough knowledge of cultivated soils is necessary for their informed and sustainable management. This study was carried out to gain a better understanding of cropped soils in the Eastern Cape Province of South Africa. The mineralogical and chemical composition and nutrient status of topsoils collected from homestead gardens and fields of smallholdings in 5 of the 36 magisterial districts where smallholder farming prevails in the Province were determined. These data were supplemented with results of soil analyses conducted by an Analytical Services Laboratory that obtains its samples from the 31 magisterial districts where large‐scale farms are dominant. The soils studied were similar mineralogically, and all had a clay fraction that was dominated by quartz, mica, and/or kaolinite, which is fairly typical for many tropical and subtropical soils. Elemental analysis showed that the soils were generally low to very low in their total content of nutrients, except for sulfur (S), manganese (Mn), zinc (Zn), copper (Cu), and boron (B), reflecting the marine and sedimentary nature of their parent materials. The available nutrient status of the cultivated soils was generally low to very low, especially those found in smallholder fields. This was attributed to low soil organic matter levels and low geological reserves of some nutrients notably phosphorus (P), potassium (K), and calcium (Ca), coupled with continuous cultivation of the lands without adequate nutrient replenishment. Depending on location, 75–100% of the fields tested low in pH, 62–100% were low in organic carbon, 83–100% were low in extractable K, 62–93% were low in extractable Ca, and 79–100% were deficient in available phosphorus. The nutrient status of soils receiving moderate to high amounts of nutrients was generally satisfactory, as revealed by the nutrient content of garden soils found on smallholdings and the fields on large‐scale farms. In all cases, soil pH was low to critically low. The findings are used to propose a soil fertility management strategy for the communal areas of the Province.     

甘肃梯田资源现状及发展探讨

新中国成立以来,甘肃的梯田建设得到了快速发展,截至2005年底,全省已建成梯田186.46万hm2,为区域经济的发展构筑了平台,梯田已成为广大山区农业增效、农民增收的基础工程。分析了梯田的利用途径:大部分以种植满足粮食生产的农作物为主,约占梯田总量的80%,部分靠近村庄、水源的梯田发展蔬菜、果业等经济产业。结合实际,从新资源培育、产业开发、建设机制三个方面对新的历史条件下的梯田发展进行了探讨。     

东北平原土壤速效养分状况与分布研究

应用GPS定位技术,对整个东北平原土壤按20 km×20 km的网格分0~20 cm和20~40 cm两层进行取样,对土壤速效养分状况与分布进行了研究。结果表明,东北平原0~20 cm的表层土壤中,土壤速效氮、磷、钾、硫和锌的缺乏面积分别为18.5%、28.6%、51.1%、78.6%和44.7%。三江平原土壤养分状况良好,嫩江平原次之,辽河平原较差,因此应对3个区域采取不同的施肥措施。     

刈割对白三叶草生长状况及土壤养分的影响

在连续2 a内不施肥,每次刈割并全部取走地上部分的条件下,通过测定白三叶的生物量、生长因子及土壤有机质、全量养分、水解N、有效P和速效K等指标,了解生长状况及其对土壤养分的影响.结果表明,随刈割次数的增加,白三叶鲜重、干重、平均高度和径粗均呈下降趋势,年均降幅分别为14.34%,13.12%,5.20%和3.38%;表层土壤有机质下降最大为24.37%,最小为8.75%,白三叶草对表层土壤全量养分影响不明显,但对土壤速效养分影响显著,2 a间最大降幅分别为46.56%,43.63%,16.69%;底层土中的有机质和全量养分相似于表层土,速效养分中有效磷受到的影响最大,而水解氮和速效钾较小.经综合分析,增加刈割次数会导致土壤整体供肥能力下降,生产力降低.因此,为了草地的可持续经营,刈割后须施入适量的复合肥、钾肥和磷肥.