Results 71 to 80 of about 2,562 (169)

The Effect of Oxalic and Acetic Acid on the Desorption of Phenanthrene in Mangrove Sediment [PDF]

open access: yes, 2010
目前,有关红树林湿地有机污染物的研究主要集中在有机污染物在湿地沉积环境中的时空分布及红树林生态系统对有机污染物的降解两个方面,有关红树植物根系分泌物对沉积物中有机污染物吸附行为影响的研究尚不多见;而相关研究对于揭示有机污染物在滨海河口湿地根-土界面的迁移机制,探讨有机污染物的植物修复机理具有重要意义。本文以不同类型的红树林沉积物为研究对象,以菲为多环芳烃的代表,以草酸和乙酸为红树根系分泌物中小分子有机酸的代表,应用振荡平衡法,研究了不同浓度外源菲进入红树林沉积物后的吸附/解吸差异,探讨了根系分泌物(草酸、
叶菁
core  

水土保持森土壤肥力及其评价指标

open access: yesShuitu Baochi Xuebao, 2000
水土保持林作为保持水土、防止土壤侵蚀的特有林种,对于提高土壤肥力具有重要作用。常见的评价土壤肥力的指标有土壤酶活性、土壤有机质含量、土壤有机-无机复合体和微团聚体、土壤颗粒组成、土壤微生物数量以及土壤的其它理化性状等。通过分析不同水土保持林的土壤酶活性和土壤有机质含量。对其土壤肥力进行了评价。结果表明,有林地土壤肥力高于无林地;油松-阔叶树混交林土壤肥力比油松纯林更高;同一林分随着林龄的增长 ...
沈慧 郭浩
doaj  

Impacts of storm event on DOM composition and flux in two Jiulong Tributaries with different watershed features [PDF]

open access: yes, 2016
通过调查2014年7月"麦德姆"台风影响期间福建九龙江北溪(流域以林地为主)和西溪(农业流域和城市背景)下游定点站DOM的时间序列,测定样品的DOC含量及其吸收光谱和三维荧光光谱,以评估不同流域背景对河流DOM动力学降雨响应的差异性,并为流域-河口系统的一体化管理提供重要参考。降雨期间,两条河流DOC浓度、吸收系数aCDOM(350)以及总荧光强度均随径流量升高而增大,并在水位下降期持续增加,且西溪增加量明显高于北溪,说明受人类活动扰动大的流域河流有机质对暴雨事件的响应更为灵敏 ...
徐静   +5 more
core  

Effects of Chemical Fertilizer Reduction Combined with Straw and Organic Fertilizer Application on Soil Acidification Mitigation and Erosion Control [PDF]

open access: yes
[Objective] To demonstrate that appropriate application of straw and organic fertilizer can effectively improve soil quality, have a positive effect on soil acidification mitigation and erosion control.
CAO Yunfei   +9 more
core   +1 more source

Effects of Different Logging Residue Treatments on Acid Hydrolyzed Soil Organic Carbon Fractions and Soil Microbial Communities in a Chinese Fir Plantation [PDF]

open access: yes
[Objective] Acid hydrolyzed soil organic carbon fractions are important in soil, and the changes of their contents will affect soil microbial community composition.
GUO Jianfen   +5 more
core   +1 more source

不同耕作制度对紫色水稻土活性有机质及碳库管理指数的影响

open access: yesShuitu Baochi Xuebao, 2007
以长期定位试验点的紫色水稻土为研究对象,研究了耕作制度对紫色水稻土活性有机质和碳库管理指数的影响。结果表明:稻田长期垄作免耕0~10cm土层有机质含量比常规平作高,10~60cm土层有机质含量则比常规平作低;表明稻田长期垄作免耕土壤有机质具有表层富集现象;水旱轮作各土层有机质含量均比常规平作低。垄作免耕各土层活性有机质含量普遍增加,水旱轮作表层(0~10cm)活性有机质含量减少,其余土层变化不大。对活性有机质组分含量的研究表明:与常规平作相比,垄作免耕增加了土壤表层活性有机质各个组分的含量 ...
罗友进, 王子芳, 高明, 魏朝富
doaj  

Insist on the Strategy of Forestry Sustainable Developmnet [PDF]

open access: yes, 1999
该文分析比较了前人在杉木林和火力楠林两种林分的林冠、枯枝落叶层、土壤结构与肥力、土壤微生物等因素保持水土方面的研究成果,从战略上提出了长泰县林业可持续发展对策。The paper analyzes and makes comparison among the research achievements in water and soil conservation by leaves, defoliation layer,soil structure and fertility, soil ...
史大林, 洪海征, 黄璜
core  

不同氮素水平下生物质炭、秸秆添加对陇中黄土高原旱作农田土壤活性有机碳的影响

open access: yesShuitu Baochi Xuebao, 2020
针对黄土高原旱地小麦产量和土壤肥力水平低的问题,为更好地提升土壤肥力,达到稳产增产的效果,通过布设在定西李家堡镇的长期定位试验,研究了3种氮素(N)水平下(不施氮,施氮50 kg/hm2,施氮100 kg/hm2)生物质炭(B)、秸秆(S)添加(共9个处理)对陇中黄土高原旱作农田土壤有机碳及活性有机碳的影响。结果表明:相比于不施氮肥(CNO),其余施肥方式均可显著提升土壤有机碳含量,且以BN100的效果最为显著,0—5,5—10,10—30 cm土层分别提升了84.7%,69.3%,47.8%,BN0 ...
郭万里   +6 more
doaj  

Response Characteristics of Soil Saturated Hydraulic Conductivity after Returning Orchard to Farmland on the Loess Plateau [PDF]

open access: yes
[Objective] To explore the change rule and influencing factors of soil saturated hydraulic conductivity (Ks) after returning orchard to farmland. [Methods] Aging apple orchards (AO) and orchards with different tillage years (2 a, 4 a, 6 a, 10 a) on the ...
JIA Xiaoxu   +6 more
core   +1 more source

碳氮添加对雨养农田土壤全氮、有机碳及其组分的影响

open access: yesShuitu Baochi Xuebao, 2019
为探明碳氮添加4年后,土壤全氮、有机碳及其组分(可溶性有机碳、微生物量碳、轻组和重组有机碳)的变化特征,依托布设于甘肃省定西市安定区李家堡镇的不同碳源配施氮素田间定位试验,涉及秸秆、生物质炭、氮素3个因素,秸秆设置为不施、施用秸秆2水平)生物质炭为不施和施用生物质炭2个水平)氮素设置为不施氮、施纯氮50 kg/hm2、施纯氮100 kg/hm2 3个水平,共9个处理。结果表明:不同处理下土壤全氮、有机碳及其组分的含量均随土层的加深而降低。添加生物质炭对土壤全氮、有机碳及其组分均具有不同程度的提升效应 ...
江晶   +4 more
doaj  

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