Soil attributes and plant production changes in a tropical littoral wetland
Soil attributes and plant production changes in a tropical littoral wetland
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热带滨海湿地土壤属性和植物生产变化
DOI：
10.1002/jpln.201400258
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发表时间：
2015
影响因子：
2.5
通讯作者：
C. Becker
中科院分区：
文献类型：
--
作者：
C. Becker
奈瓦沙湖是东非裂谷的一个淡水湖。随着1980至2011年间湖泊水位的持续下降，新暴露的土地面积逐渐被用作农业用途。由此产生的时间序列可以分析土地利用持续时间对养分动态和农业生产的影响。样带代表0-30年(农田)和15-30年(牧场)土地利用年限的样带建立在冲积和湖泊沉积形成的土壤上。我们评估了随着土地利用时间的延长，表层土壤氮(N)储量(t ha−1)、铵矿化潜力(N供应能力)和植物速效P的变化。另一项温室试验研究了从不同土地利用类型和时序位置采集的盆栽表土中吉库尤草和玉米的反应。随着土地利用时间的延长，我们注意到牧场和农田利用下的土壤氮含量都显著下降(P<；5%)，遵循指数衰减模型。在草地土壤中，N储量在15年内减少84 kg ha−1a−1，衰变速率常数为0.019 a−1；在农田土壤中，N储量在30年内减少75 kg ha−1a−1，衰变速率常数为0.013 a−1。氨氮矿化潜力也随着土地利用年限的延长而降低，但这种趋势仅在湖相牧场土壤中表现显著。植物速效磷没有表现出与土地利用年限相关的任何趋势。随着使用年限的增加，吉库尤草和玉米的干物质和氮素积累较少。这种生物量的积累与土壤N显著相关。土壤有机质的持续矿化可能是土壤N耗竭的原因之一。奈瓦沙湖滨海湿地地带的持续农业利用可能导致牧场和粮食作物的生产潜力下降。
Lake Naivasha is a freshwater lake in the East African Rift Valley. With continued lake level declines between 1980 and 2011, the newly exposed land areas were gradually taken for agricultural use. The resulting chronosequences allow for an analysis of the effects of land use duration on nutrient dynamics and agricultural production. Transects representing land use durations of 0–30 (cropland) and 15–30 years (pasture) were established on soils formed on alluvial deposits and lacustrine sediments. We assessed changes in topsoil nitrogen (N) stocks (t ha−1), ammonium mineralization potential (N‐supplying capacity), and plant‐available P with increasing durations of land use. An additional greenhouse experiment studied the responses of kikuyu grass (Cenchrus clandestinus) and maize (Zea mays) in potted topsoil collected from differnt land‐use types and chronosequence positions. With increasing duration of land use we noted a significant decline (P< 5%) in soil N contents under both pasture and cropland uses, following a model of exponential decay. The N stocks decreased at 84 kg ha−1a−1and a decay rate constant of 0.019 a−1in pasture soil within 15 years, and at 75 kg ha−1a−1with a decay rate‐constant of 0.013 a−1in cropland soil within 30 years. While the ammonium‐N mineralization potential also decreased with land use duration, the trends were significant only in lacustrine pasture soils. Plant‐available P did not show any trends that were related to the duration of land use. Kikuyu grass and maize accumulated less dry matter and N as the duration of use increased. This biomass accumulation was significantly related to soil N. A continued mineralization of soil organic matter has possibly contributed to the observed soil N depletion over time. The continuous agricultural use of the littoral wetland zone of Lake Naivasha is likely to entail declining production potentials for both pastures and food crops.
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热带沼泽养分的季节性变化：肯尼亚奈瓦沙湖北部沼泽
DOI：
--
发表时间：
1979
期刊：
影响因子：
--
作者：
J. Gaudet
通讯作者：
J. Gaudet
影响因子：
2.9
作者：
Ludger Bornemann;M. Herbst;G. Welp;H. Vereecken;W. Amelung
通讯作者：
Ludger Bornemann;M. Herbst;G. Welp;H. Vereecken;W. Amelung
使用贝叶斯网络模型将非洲纸莎草湿地的水文、生态系统功能和生计成果联系起来
DOI：
--
发表时间：
2013
期刊：
Wetlands (Wilmington, N.C.)
影响因子：
--
作者：
A. Dam;J. Kipkemboi;M. M. Rahman;G. Gettel
通讯作者：
G. Gettel
昆士兰州南部连续耕作和谷物种植土壤肥力的长期趋势。
DOI：
--
发表时间：
1987
期刊：
影响因子：
--
作者：
R. Dalal;R. Mayer
通讯作者：
R. Mayer
农业利用动态对东非湿地土壤特性和作物反应有不同影响
影响因子：
1.8
作者：
H. Kamiri;C. Kreye;M. Becker
通讯作者：
M. Becker