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991.
"MsoNormal ">BAO Wan-kui; LEI Qiu-liang; JIANG Zhuo-dong; SUN Fu-jun; ZHANG Tian-peng; HU Ning; WANG Qiu-bing 《农业科学学报》2025,22(9)
土壤温度状况对土壤分类和土地利用至关重要。按照中国土壤系统分类;土壤温度状况通常是依据土表下50 cm深度处的年均土壤温度（MAST50）来确定的。然而;由于缺乏多年实测数据且难以准确估算MAST50;中国土壤温度状况的预测和划分目前仍然是土壤学研究的关键问题。本研究通过探究MAST50空间分布与环境因素之间的关系;预测MAST50在全国范围内的空间分布;并生成中国土壤温度状况空间分布图。本研究基于全国386个国家气象站1971-2000年的MAST50;以及全国2048个国家气象站1971-2000年的年均气温（MAAT）;利用集成线性回归克里格模型;建立了用以预测我国各个区域MAST50的分区土壤转换函数模型。研究结果表明;MAAT是影响MAST50最重要的环境因素。本研究进一步评估所建立模型的精度;基于验证数据集的分区模型平均绝对误差（MAE）和均方根误差（RMSE）分别是0.66相似文献
992.
镉（Cd）不仅是环境中毒性最大的重金属之一;而且在土壤中具有较低的环境容量;控制镉进入土壤刻不容缓。土壤中镉的来源众多;其中大气沉降已被证明是中国大规模土壤镉污染的主要来源。因此;确定镉的人为排放、大气沉降和土壤中镉累积之间的定量关系;对于缓解镉的非点源污染具有非常重要的意义。因此;本研究以中国长江中下游平原为例;基于2000-2020年发表文献中的大气排放-沉降-土壤累积数据集;研究了大气排放、大气沉降和土壤Cd累积之间的关系。结果表明;近十年来;土壤Cd仍在累积;平均累积率从9.45下降到8.86 μg kg yr;依然远超全国平均水平（4.0 μg kg yr）。大气沉降通量对土壤Cd增量的贡献在22-29%之间;大气沉降通量从0.54下降到0.48 mg m;但仍高于全国平均水平。在一个省级行政区域内;大气沉降和排放高度相关;接近1.0的比例;而多种因素增加了其不确定性。由于控制技术和环境政策的影响;大气重金属排放因子可能处于动态变化状态。作为镉排放的主要来源;2000-2010年至2010-2020年期间;有色金属生产每吨烟尘排放量下降了64.7%。尽管各种环境政策已经出台;但镉的大气排放仍然不容乐观。这项工作为合理控制镉的大气排放和土壤污染提供了科学依据。 相似文献
993.
"MsoNormal ">Minghui Cao; Yan Duan;Minghao Li; Caiguo Tang; Wenjie Kan;Jiangye Li; Huilan Zhang; Wenling Zhong;Lifang Wu 《农业科学学报》2025,23(2)
合成氮肥对提高土壤肥力和作物产量方面发挥着重要作用;但过量施用氮肥会造成土壤酸化、地下水污染和生物多样性减少等农业生态系统风险。同时;通过有机肥替代化肥因其生态环境友好性和产量效益而日益受到重视。然而;粪肥替代、作物产量和潜在的微生物机制之间的联系仍不清晰。为了填补这一空白;本研究在砂姜黑土区开展了为期三年的田间试验;包括以下五种施肥方案:1）对照;不施肥; 2）CF;化肥（无粪肥替代）;3）CF相似文献
994.
"MsoNormal ">Qiuyan Yan;Linjia Wu; Fei Dong; Shuangdui Yan; Feng Li;Yaqin Jia; Jiancheng Zhang; Ruifu Zhang;Xiao Huang 《农业科学学报》2025,23(1)
休闲期耕作有利于旱地小麦蓄水增产。然而;目前生长季土壤有机碳（SOC）、全氮（TN）和速效养分对耕作方式的响应尚不清楚。本研究通过5年试验评价了三种耕作方式（NT;免耕;SS;深松;DT;深翻）对土壤物理化学性质的影响;并分析了第5年试验收获期土壤团聚体结构及团聚体碳氮组分。结果表明;与NT相比;SS和DT同时提高了小麦的产量、秸秆生物量和秸秆碳投入。与DT和NT相比;SS通过提高0-40 cm土层SOC相似文献
995.
Xianglin Zhang; Jie Xue; Songchao Chen; Zhiqing Zhuo; Zheng Wang; Xueyao Chen; Yi Xiao; Zhou Shi 《农业科学学报》2025,23(8)
面对日益严重的全球土壤退化问题;明确农田土壤有机质的空间分布格局对于土壤碳库核算、农田质量评价和制定有效的管理政策具有重要意义。作为一种空间信息预测技术;数字土壤制图已被广泛应用于不同区域尺度的土壤信息空间制图上。然而;由于精确量化人为干扰因素存在较大的难度;针对农田尺度的土壤有机质制图反演模型的精度往往低于其它土地覆被类型。为解决该问题;本研究使用2021年广州采集的462个农田土壤样本系统评估“信息提取-特征选择-模型融合”框架在提升农田土壤有机质反演精度的潜力。本研究证明“信息提取-特征选择-模型融合”框架可以在有效提升最终反演结果的精度（R相似文献
996.
西藏自治区日喀则市耕地地力匮乏,气候干旱冷凉,土壤温湿度较低,不利于马铃薯的正常生长和发育。而秸秆覆盖能够调节土壤温度和湿度条件,为马铃薯生长创造更加适宜的微环境。为探究地膜和添加不同厚度秸秆对马铃薯农田土壤温湿度及产量的影响,试验设置5个处理,包括常规种植（CK1）、覆膜种植处理（CK2）、添加秸秆3 cm处理（T1）、添加秸秆6 cm处理（T2）和添加秸秆9 cm处理（T3）。结果表明, T3处理增温保湿效果虽然低于CK2,但均高于其他处理,具备一定的保湿蓄热作用;生育期较对照提前,但无显著差异;株高较其他处理矮,但茎粗相对较粗,生育性状虽不及覆膜处理好,但利于增产;单株产量与CK2无显著差异,比CK1显著增产33.3%;单株薯数比CK1增加43.9%;公顷产量比CK1增产17.4%,但比覆膜处理有所减产。由于覆膜处理存在农事操作的复杂性和塑料薄膜环境污染问题,因此,采用适当厚度的秸秆覆盖代替塑料覆膜,更适合西藏自治区日喀则市绿色马铃薯生产的需求。 相似文献
997.
土壤有机碳（SOC）和氧化铁（Fe）是驱动土壤团聚体形成和稳定的重要因素。然而;在施用有机肥的设施土壤中;这些驱动因素的机制尚不清楚。我们在为期3年的田间试验中;研究影响设施土壤团聚体稳定性的因素。为了探讨有机肥对土壤团聚体的影响;我们共设四个处理:不施肥（CK）;无机肥料（CF）;有机肥（OF）;无机和有机肥配施（COF）。施用有机肥显著提高了团聚体的稳定性;即提高了0.25 mm粒级团聚体含量、平均重量直径和几何平均直径。OF和COF处理增加了SOC含量;特别是提高了0.25 mm粒级团聚体中构成SOC的脂芳碳、芳香碳和多糖碳含量。施用有机肥显著增加了土壤和团聚体中游离氧化铁（Fed）、无定形氧化铁（Feo）和非晶态铁的含量。此外;非晶态铁与土壤和团聚体中的SOC含量呈正相关。非晶态铁和SOC均与2mm粒级MWD呈正相关。总体而言;我们认为施用有机肥后土壤中SOC、芳香碳和非晶态铁含量的增加是提高土壤团聚体稳定性的原因。 Abstract Both soil organic carbon (SOC) and iron (Fe) oxide content, among other factors, drive the formation and stability of soil aggregates. However, the mechanism of these drivers in greenhouse soil fertilized with organic fertilizer is not well understood. In a 3-year field experiment, we aimed to investigate the factors which drive the stability of soil aggregates in greenhouse soil. To explore the impact of organic fertilizer on soil aggregates, we established four treatments: no fertilization (CK); inorganic fertilizer (CF); organic fertilizer (OF); and combined application of inorganic and organic fertilizers (COF). The application of organic fertilizer significantly enhanced the stability of aggregates, that is it enhanced the mean weight diameter, geometric mean diameter and aggregate content (%) of 0.25 mm aggregate fractions. OF and COF treatments increased the concentration of SOC, especially the aliphatic-C, aromatic-C and polysaccharide-C components of SOC, particularly in 0.25 mm aggregates. Organic fertilizer application significantly increased the content of free Fe (Fed), reactive Fe (Feo), and non-crystalline Fe in both bulk soil and aggregates. Furthermore, non-crystalline Fe showed a positive correlation with SOC content in both bulk soil and aggregates. Both non-crystalline Fe and SOC were significantly positively correlated with 2 mm mean weight diameter. Overall, we believe that the increase of SOC, aromatic-C, and non-crystalline Fe concentrations in soil after the application of organic fertilizer is the reason for improving soil aggregate stability.
998.
999.
"MsoNormal "> " ">Weixiao Tang Yi Lü Rong Zhang Xin Wang Haiyan Wang Mei Wang Xuesen Chen Xiang Shen Chengmiao Yin Zhiquan Mao 《农业科学学报》2025,24(3)
苹果再植病（ARD）主要由生物因素引起;严重制约了苹果产业的发展。采用生物防治措施缓解 ARD 对苹果产业的可持续发展至关重要。以平邑甜茶幼苗和嫁接苗（Fuji New2001/M9T337）为试验材料;在盆栽和大田条件下研究了生氨基酸粉和哈茨木霉菌肥对植株生物量、叶片指标、根系指标、土壤理化性质、土壤酶活性和土壤真菌群落的影响。我们发现;施用两种物质显著促进了植物生长;提高了叶片光合作用、叶绿素含量、根系呼吸速率、根系抗氧化酶活性和土壤酶活性;显著降低了土壤中镰刀菌数量;显著提高了有益菌的丰度。综上所述;生氨基酸粉与哈茨木霉菌肥混施是防治ARD的有效方法。 相似文献
1000.
Land use practice significantly affects soil properties. Soil is a major sink for atmospheric carbon, and soil organic carbon (SOC) is considered as an essential indicator of soil quality. The objective of this study was to assess the effects of N and P applied to Suaeda salsa on biomass production, SOC concentration, labile organic carbon (LOC) concentration, SOC pool and carbon management index (CMI) as well as the effect of the land use practice on soil quality of coastal tidal lands in east coastal region of China. The study provided relevant references for coastal exploitation, tidal land management and related study in other countries and regions. The field experiment was laid out in a randomized complete block design, consisting of four N-fertilization rates (0 (N0), 60 (N1), 120 (N2) and 180 kg ha-1 (N3)), three P-fertilization rates (0 (P0), 70 (P1) and 105 kg ha-1 (P2)) and bare land without vegetation. N and P applied to S. salsa on coastal tidal lands significantly affected biomass production (above-ground biomass and roots), bulk density (ρb), available N and P, SOC, LOC, SOC pool and CMI. Using statistical analysis, significantly interactions in N and P were observed for biomass production and the dominant factor for S. salsa production was N in continuous 2-yr experiments. There were no significant interactions between N and P for SOC concentration, LOC concentration and SOC pool. However, significant interaction was obtained for CMI at the 0-20 cm depth and N played a dominant role in the variation of CMI. There were significant improvements for soil measured attributes and parameters, which suggested that increasing the rates of N and P significantly decreased ρb at the 0-20 cm depth and increased available N and P, SOC, LOC, SOC pool as well as CMI at both the 0-20 and 20-40 cm depth, respectively. By correlation analysis, there were significantly positive correlations between biomass (aboveground biomass and roots) and SOC as well as LOC in 2010 and 2011 across all soil depth, respectively. The treatment with N at 180 kg ha-1 and P at 105 kg ha-1 was superior to the other treatments. The results from the 2-yr continuous experiments indicated that, in short-term, there were a few accumulation of SOC and LOC concentrations by means of N and P application to S. salsa, whereas in the long run, S. salsa with N and P application was recommended for coastal tidal lands because of its great potential of carbon sequestration, improvements of soil nutrition status and promotion of soil quality. Abstract Land use practice significantly affects soil properties. Soil is a major sink for atmospheric carbon, and soil organic carbon (SOC) is considered as an essential indicator of soil quality. The objective of this study was to assess the effects of N and P applied to Suaeda salsa on biomass production, SOC concentration, labile organic carbon (LOC) concentration, SOC pool and carbon management index (CMI) as well as the effect of the land use practice on soil quality of coastal tidal lands in east coastal region of China. The study provided relevant references for coastal exploitation, tidal land management and related study in other countries and regions. The field experiment was laid out in a randomized complete block design, consisting of four N-fertilization rates (0 (N0), 60 (N1), 120 (N2) and 180 kg ha-1 (N3)), three P-fertilization rates (0 (P0), 70 (P1) and 105 kg ha-1 (P2)) and bare land without vegetation. N and P applied to S. salsa on coastal tidal lands significantly affected biomass production (above-ground biomass and roots), bulk density (ρb), available N and P, SOC, LOC, SOC pool and CMI. Using statistical analysis, significantly interactions in N and P were observed for biomass production and the dominant factor for S. salsa production was N in continuous 2-yr experiments. There were no significant interactions between N and P for SOC concentration, LOC concentration and SOC pool. However, significant interaction was obtained for CMI at the 0-20 cm depth and N played a dominant role in the variation of CMI. There were significant improvements for soil measured attributes and parameters, which suggested that increasing the rates of N and P significantly decreased ρb at the 0-20 cm depth and increased available N and P, SOC, LOC, SOC pool as well as CMI at both the 0-20 and 20-40 cm depth, respectively. By correlation analysis, there were significantly positive correlations between biomass (aboveground biomass and roots) and SOC as well as LOC in 2010 and 2011 across all soil depth, respectively. The treatment with N at 180 kg ha-1 and P at 105 kg ha-1 was superior to the other treatments. The results from the 2-yr continuous experiments indicated that, in short-term, there were a few accumulation of SOC and LOC concentrations by means of N and P application to S. salsa, whereas in the long run, S. salsa with N and P application was recommended for coastal tidal lands because of its great potential of carbon sequestration, improvements of soil nutrition status and promotion of soil quality.