砖红壤速效磷3种测定方法的比较

用Ｏｌｓｅｎ、Ｂｒａｙ－１和Ｍｅｈｌｉｃｈ－３三种方法对不同植被下的砖红壤进行速效磷的测定比较。结果表明：种植橡胶的土壤磷,Ｂｒａｙ－１法和Ｍｅｈｌｉｃｈ－３法间有较好的一致性,且呈显著相关;种植甘蔗的土壤磷,三种方法间均呈极显著相关;而种植其它植物的土壤磷,方法间的一致性较差,相关也不显著。一般情况下,建议不要用Ｍｅｈｌｉｃｈ－３作为砖红壤速效磷的提取剂。     

BOLTZMANN方程与碰撞矩阵元的计算

作者用Ｂｕｒｎｅｔｔ函数作为展开基底表示分子速度分布函数和Ｂｏｌｔｚｍａｎｎ方程，并由此证明，Ｂｏｌｔｚｍａｎｎ碰撞矩阵元的计算归结为约化积分、Ｃｌｅｂｓｃｈ－Ｇｏｒｄａｎ系数和Ｂｒｏｄｙ－Ｍｏｓｈｉｎｓｋｙ系数的计算。为了提高计算效率，作者将这些系数用超几何函数予以表示，并由此提出了高效的计算方法。     

鞍山地区陈台沟变质表壳岩的年龄

鞍山市东部陈台沟村附近，有一套以斜长角闪岩类、石英岩类和长英质片麻岩类等组成的变质表壳岩（陈台沟表壳岩），它虽被划归为鞍山群但同该地区公认的鞍山群明显不同。它同白家坟花岗岩（３．８Ｇａ）和陈台沟花岗岩（３．３Ｇａ－３．１Ｇａ）为断层接触。采用Ｋｏｂｅｒ提出的单颗粒锆石逐层蒸发－沉积方法，测定了侵入陈台沟表壳岩的两条花岗岩脉（Ａ９２１２－３，Ｃｈ１０）中锆石的年龄，Ａ９２１２－３测定了８粒锆石，年龄为３３５７±４Ｍａ－３３１５±４Ｍａ（误差均为２ｄ，Ｃｈ１０测定了３粒锆石，结果为３３３７±１２Ｍａ，３２２８±３７Ｍａ和１８１３±７Ｍａ。３３５７Ｍａ和３３３７Ｍａ是这两条花岗岩脉侵位时间。１８１３Ｍａ是后期地质作用的时间。陈台沟表壳岩的年龄大于３．３５Ｇａ，建议将陈台沟表壳岩从鞍山群分离出来单独建群。     

水体中NH3—N对建鲤非特异性免疫功能的影响

用０．１、０．５、１．０、２．０和５．０ｍｇ／Ｌ ＮＨ３－Ｎ分别刺激建鲤１０ｄ后,测定了建鲤非特异性免疫指标,估测不同浓度的ＮＨ３－Ｎ对建鲤非特异性免疫指标的影响。０．１、０．５ｍｇ／Ｌ的ＮＨ３－Ｎ对建鲤ＮＢＴ阳性细胞、溶菌酶活性无影响,１．０ｍｇ／Ｌ的ＮＨ３－Ｎ可使ＮＢＴ阳性细胞数和溶菌酶活性降低,而２．０和５．０ｍｇ／Ｌ则使ＮＢＴ阳性细胞数和溶菌酶活性显著下降（Ｐ〈０．０５）。这些结果表明水体中０．１、０．５ｍｇ／Ｌ的ＮＨ３－Ｎ对建鲤非特异性免疫功能无影响,１．０ｍｇ／Ｌ的ＮＨ３－Ｎ略有影响,而２．０和５．０ｍｇ／Ｌ的ＮＨ３－Ｎ则明显降低了建鲤的非特异性免疫功能。     

湛江地区辣椒地土壤的养分状况及其调节

对湛江地区辣椒地土壤取样,测定了容重pH、及有机质、全氮、碱解氮、速效磷、速效钾含量。结果表明,辣椒地土壤肥力比甘蔗地土壤有明显改善,且随年限延长呈提高的趋势;与甘蔗地土壤比较,辣椒地土壤速效钾含量呈降低趋势。     

大鳍Hu的生长,死亡及合理利用研究

用ＳＡＳ统计软件拟合了大鳍Ｈｕ的体长生长方程和体重生长方程：Ｌｔ＝７９．５（１－３＾０．０５３３（ｔ＋２．０９８２）,Ｗｔ＝３３７０（１－ｅ＾－０．０５３３（ｔ＋２．０９８２）＾２．７７４４,并估算了其自然死亡系数Ｍ,捕捞死亡系数Ｆ。应用Ｂｅｖｅｒｔｏｎ－Ｈｏｌｔ模式,研究了嘉陵江水系大鳍Ｈｕ的资源状况,为开发利用提供科学依据。     

红海湾养殖区底质水中氮,磷的分布特征

着重研究了红海湾养殖区底质水中ＮＯ３＾－－Ｎ、ＮＯ２＾－－Ｎ、ＮＨ４＾＋－Ｎ、ＰＯ４＾３－－Ｐ、有机质及ｃ（ＮＯ３＾－－Ｎ）／ｃｐ和∑ｃｎ／ｃｐ（∑ｃｎ＝ｃ（ＮＯ２＾－）＋ｃ（ＮＯ３＾－）＋ｃ（ＮＨ４＾＋）比值的分布特征,并对该湾低质水中氮、磷及有机质的季节变化及其它们之间的相互关系作了讨论,结果表明：在春、夏、;冬三个季节中,ＮＨ４＾＋－Ｎ的浓度比ＮＯ２＾－－Ｎ及ＮＯ３＾－－Ｎ高,春季ＮＨ４＾＋－Ｎ平均浓度为９２．６０μｍｏｌ／Ｌ,占总无机氮８０．５７％;夏季浓度为４７．０４μｍｏｌ／Ｌ,占总无机氮６１．６４％;冬季ＮＨ４＾＋－Ｎ的浓度最低,为９．６０μｍｏｌ／Ｌ,占总无机氮４５．７６％;而夏季ＰＬ４＾３－－Ｐ浓度及有机质的含量比春、冬季高,分别为５３．６８μｍｏｌ／Ｌ和１．３６２％。分析指出该湾底质水中无机     

基于野外 Ｇｕｅｌｐｈ入渗法与室内变水头达西法的土壤饱和渗透系数变化规律

为揭示土壤饱和渗透系数的变化规律,在江汉平原杨林尾－陆溪口地区分别采用 Ｇｕｅｌｐｈ入 渗仪 和 改 进 的 ＴＳＴ－５５型土壤渗透仪开展了土壤饱和渗透系数实验。结果表 明:采 用 Ｇｕｅｌｐｈ入渗法在粉砂质黏壤土中测得冲积物饱和渗透系数相对较大,数量级在１０－２ ～１０－１之间,最高达到７．５０×１０－１ ｍ／ｄ,最小为１．４０×１０－２ ｍ／ｄ;湖积物饱和渗透系数在１．８６×１０－３ ～４．９９×１０－２ ｍ／ｄ之间;而残积物的为６．０５×１０－３ ｍ／ｄ,相对较小;同为粉砂壤 土,相同水位埋深条件下甘蔗地和小麦地（同 为 耕 地）的土壤饱和渗透系数明显比林地的大,这与土壤翻耕及根 系、虫孔发育等有关;在相同水位埋深条件下,粉砂壤土的土壤饱和渗透系数普遍比粉砂质黏壤土的大,主要是因 为粉砂质黏壤土比粉砂壤土的黏粒比重大、孔隙比相对较小的缘故。室内变水头达西法和 Ｇｕｅｌｐｈ入渗法测得的土壤饱和渗透系数分别介于５．４３×１０－５ ～２．１０×１０－３ ｍ／ｄ和１．５７×１０－３ ～７．５０×１０－１ ｍ／ｄ之间。室内 变 水 头 达西法所测结果明显偏小,主要原因包括:①Ｇｕｅｌｐｈ入渗法进行现场原位测试时,土壤有效直径相对于室内变水 头达西法使用的环刀直径要大得多;②室内变水头达西法所用土样为单一岩性,而 Ｇｕｅｌｐｈ入渗法为原位土层,常 常具有双层或多层结构;③Ｇｕｅｌｐｈ入渗试验期间恰逢雨季,地下水位埋深小,当支持毛细水带接近地表时,Ｇｕｅｌｐｈ 入渗试验将受支持毛细水的影响,从而使 Ｇｕｅｌｐｈ入渗法所测得的结果产生误差。      

福州市农田土壤养分空间变异特征

研究农田土壤养分空间分布特征及变异规律,分析地形因子对土壤养分空间分布的影响,对土壤养分的有效利用与管理具有重要意义。本文采用GIS和地统计学相结合的方法,揭示东南丘陵区福州市农田土壤养分（有机质、碱解氮、有效磷和速效钾）的空间分布特征和变异规律,并进一步探讨土壤养分含量与地形因子（地形起伏度、高程、地形湿度指数、沉积运输指数和坡度）之间的相关性。结果表明：福州市农田有机质、碱解氮、有效磷和速效钾含量范围分别为1.10~89.5 g/kg、 1.00~461 mg/kg、0.300~298 mg/kg、和4.00~399 mg/kg,其变异系数范围为35.3%~99.0%,均属于中等变异水平;区域内耕地土壤养分存在明显的空间丰缺差异,大部分地区有机质和有效磷含量较为丰富,碱解氮含量处于中等偏上水平,速效钾含量相对较低;有机质、碱解氮、有效磷和速效钾的块金系数分别为32.0%、37.3%、50.0%和50.0%,均呈中等强度空间自相关,表明同时受到结构和随机因素控制;有机质和碱解氮空间自相关尺度较大,且在步长小于0.3 km时,各方向（0°、45°、90°和135°）变化平稳,为各向同性,而有效磷和速效钾变程较小,且各方向变化较复杂,为各向异性。这些结果表明,政府需加强施肥指导,保持氮肥施用量的同时,合理增加钾肥,适当降低有机肥和磷肥施用。此外,在后续调查采样时,样点布设要考虑密度和方向性,适当加密有效磷和速效钾的采样,而有机质和碱解氮采样可以在此基础上适当减少样点。     

Al／BaTiO_3／Si湿度传感器的电特性

用氩离子束镀膜法制备ＢａＴｉＯ３／Ｓｉ结构，并在４００～９００℃的温度下用氮气保护进行退火，用常规蒸铝技术制成Ａｌ／ＢａＴｉＯ３／Ｓｉ湿度传感器。用俄歇电子能谱分析ＢａＴｉＯ３膜的化学组分。采用高频电容—电压测试仪测定ＢａＴｉＯ３／Ｓｉ结构的固定电荷密度，分析固定电荷密度与退火的关系。结果表明：固定电荷密度达１０１１ｃｍ－２数量级。经９００℃、６０分钟退火后固定电荷密度下降至１９％到２０％。随着固定电荷密度的减少，湿度传感器的响应时间延长了６０％，而击穿电压提高了７倍。     

Higher species diversity occurs in more fertile habitats without fertilizer disturbance in an alpine natural grassland community

Are there some relationships among species diversity and soil chemical properties of high altitude natural grasslands？ Plant community composition and chemical properties of soil samples were compared to investigate the relationship between soil and species diversity, and the richness in Tibetan alpine grasslands. Results showed that species diversity was significantly positively related to soil organic matter （SOM）, total nitrogen （TN）, available nitrogen （AN）, total phosphorus （TP）, available phosphorus （AP）, and available potassium （AK） in the high alpine grasslands. Margalefs species richness index was also significantly positively related to SOM, TN, AN, and TP. Most soil chemical properties showed significantly positive correlation with species diversity and Margalef＇s richness index. Our results suggested that higher plant species richness index and diversity occurred in more fertile soil habitats in high altitude natural grassland community. In practice, fertilization management for the restoration of degraded grassland should be conducted with reference to the nutrient levels ofnatural grassland without the additional artificial fertilizer and with higher species-diversity and richness index.     

Investigating the Effects of Greenhouse Vegetable Cultivation on Soil Fertility in Lhasa,Tibetan Plateau

The area of land utilized for growing vegetables in greenhouses has expanded rapidly on the Tibetan Plateau over recent decades. However, the effects of greenhouses on soil fertility as well as variations in these effects between the plateau and plain remain unclear on the Tibetan Plateau. This study assessed the effects of vegetable greenhouses in the vicinity of Lhasa, using open field soil as a control. A total of 92 plough layer(0-20 cm depth) soil samples including 54 from greenhouses and 38 from open fields were taken, and soil pH, electrical conductivity(EC), total soluble salt(TS), soil organic matter(SOM), total nitrogen(TN), available phosphorus(AP), and available potassium(AK) were measured. The results reveal that, soil pH was lower 1.0 units in greenhouses than that in open field. TS was higher 82% and AP was higher 160% overall. Similarly, SOM and TN were higher 32% and 46%, respectively, while AK changed slightly at a higher 1% rate. Results also show that soil properties varied depending on cultivation time and vegetable types. Overall, pH continuously decreased with cultivation time while other soil fertility indicators reached a maximum value after nine years of cultivation before starting to decrease. The effect of leafy vegetable planting on soil was slight overall, while the impact of fruits on soil was more serious. Compared with changes in plain greenhouse soil fertility measured across the eastern China, the effects of greenhouses on soil in Lhasa remain relatively limited; and the change in the degree of soil fertility was lower and the extreme values of soil fertility occurred later in Lhasa.     

氮钾配施对生姜产量和砂姜黑土肥力的效应

研究了淮北平原砂姜黑土地区生姜氮钾配施的增产效应和对土壤养分的影响。结果表 明:氮钾配施可以大幅度提高生姜的产量,施钾的增产幅度,柴姜为15.3%～58.4%,平均增产率 为35.8%;狮子头姜产量提高18.2%～46.9%,平均增产28.7%。增施氮钾肥可有效提高土壤有 机质、全N、有效P、速效K、缓效K、有效Ca和有效Mg含量,降低NO3-盐含量,促使土壤pH趋于 中性,对全P和碱解N含量影响较小。土壤N素和P素大量盈余,不施钾时土壤K亏损严重,施钾 处理土壤钾基本上处于盈余状态,有利于维持和提高土壤肥力。     

Spatiotemporal variation of soil organic carbon in the cultivated soil layer of dry land in the South-Western Yunnan Plateau,China

The dynamics of soil organic carbon(SOC)in cropland is one of the central issues related to both soil fertility and environmental safety. However, little information is available at county level regarding the spatiotemporal variability of SOC in the southwestern mountainous region of China. Thus, this study aimed to explore spatiotemporal changes of SOC in the cultivated soil layer of dry land in Mojiang County,Yunnan Province, China. Data were obtained from the second national soil survey(SNSS) of 1985 and soil tests for fertilizer application carried out by the Mojiang Agricultural Bureau in 2006. The ANOVA test was applied to determine any significant differences between the datasets, while semivariogram analysis was performed on geostatistics via an ordinary Kriging method in order to map spatial patterns of soil organic carbon density(SOCD). The results revealed that SOCD in the cultivated soil layer significantly decreased from 3.93 kg m~(-2) in 1985 to 2.89 kg m~(-2) in 2006, with a total soil organic carbon stock(SOCS) decrease of 41.54×10~4 t over the same period. SOCS levels fell most markedly in yellow-brown soil at a rate of51.52%, while an increase of 8.70% was found in the analysed latosol. Geostatistical analysis also showed that the recorded changes in SOCD between 1985 and2006 were spatially structured. The decreasing trend might be attributed to the combined action of intense cultivation, major crop residue removal without any protective tillage measures, unreasonable fertilization and natural climatic diversity inducing a large decrease in SOC in the studied cultivated dry land region of Mojiang County. Therefore, management measures such as protective tillage should be undertaken in order to enhance soil C sequestration.     

山东省临沭县北部土壤养分特征及综合肥力评价

在山东省临沭县北部农耕区进行耕层土壤样品采集,并测定土壤pH、有机质、全量及速效氮磷钾等养分指标来表征土壤肥力,运用因子分析法、聚类分析法计算出所有样本土壤养分综合评价值并进行等级划分来评价土壤肥力。结果表明临沭县北部土壤酸化严重,有机质和全氮、速效钾含量较低,全钾、全磷、碱解氮、速效磷比较丰富。因子分析显示TN、OM、AK、AP、TP、pH是影响临沭县北部土壤养分综合状况的主要因素。临沭县北部土壤肥力水平偏低;土壤养分综合评价值(IFI)具体表现为：郑山街道>青云镇>玉山镇>临沭街道>蛟龙镇。     

The Impact of Irrigation on Bacterial Community Composition and Diversity in Liaohe Estuary Wetland

In this study, the sequencing of 16S ribosomal DNA was used to characterize the soil bacterial community composition and diversity in Liaohe estuarine wetland. Soil samples were taken from different locations in the wetland dominated by reed. Moreover, the soil quality parameters were evaluated (pH, moisture, organic matter, total nitrogen, available nitrogen, total phosphorus, available phosphorus). The results showed that the organic matter and nutrient contents were significantly higher in irrigated wetland than those in natural wetland. Major phylogenic groups of bacteria in soil samples including Proteobacteria, Acidobacteria, Gemmatimonadetes, Actinobacteria and Cyanobacteria were analyzed and we found that Proteobacteria was the most abundant in the community, and the phylum Acidobacteria was more abundant in irrigated wetland. Beta diversity analyses indicated that the soil bacterial community was mainly affected by sampling sites rather than seasons. In general, the bacterial community in natural wetland was not significantly different with that in artificial irrigated wetland. Artificial hydraulic engineering irrigated according to the water requirement rule of reed, increased the production of reeds, changed the way of wetland soil material input, but the diversity of bacterial community kept stable relatively.     

Soil organic carbon and nutrients along an alpine grassland transect across Northern Tibet

Soil carbon and nutrient contents and their importance in advancing our understanding of biogeochemical cycling in terrestrial ecosystem, has motivated ecologists to find their spatial patterns in various geographical area. Few studies have focused on changes in the physical and chemical properties of soils at high altitudes. Our aim was to identify the spatial distribution of soil physical and chemical properties in cold and arid climatic region. We also tried to explore relationship between soil organic carbon (SOC) and total nitrogen (TN), total phosphorus (TP), available nitrogen (AN), available phosphorus (AP), soil particle size distribution (PSD). Samples were collected at 44 sites along a 300 km transect across the alpine grassland of northern Tibet. The study results showed that grassland type was the main factor influencing SOC, TN and TP distribution along the Gangdise Mountain-Shenzha-Shuanghu Transect. SOC, TN and TP contents were significantly higher in alpine meadow than alpine steppe ecosystems. SOC, TN, TP and AN contents in two soil layers (0-15 cm and 15-30 cm) showed no significant differences, while AP content in top soil (0-15 cm) was significantly higher than that in sub-top soil (15-30 cm). SOC content was correlated positively with TN and TP content (r = 0.901 and 0.510, respectively). No correlations were detected for clay content and fractal dimension of particle size distribution (D). Our study results indicated the effects of vegetation on soil C, N and P seem to be more important than that of rocks itself along latitude gradient on the northern Tibetan Plateau. However, we did not found similar impacts of vegetation on soil properties in depth. Inaddition, this study also provided an interesting contribution to the global data pool on soil carbon stocks.     

Different Responses of Vegetation to Frozen Ground Degradation in the Source Region of the Yellow River from 1980 to 2018

Frozen ground degradation under a warming climate profoundly influences the growth of alpine vegetation in the source region of the Qinghai-Tibet Plateau. This study investigated spatiotemporal variations in the frozen ground distribution, the active layer thickness(ALT) of permafrost(PF) soil and the soil freeze depth(SFD) in seasonally frozen soil from 1980 to 2018 using the temperature at the top of permafrost(TTOP) model and Stefan equation. We compared the effects of these variations on vegetation growth among different frozen ground types and vegetation types in the source region of the Yellow River(SRYR). The results showed that approximately half of the PF area(20.37% of the SRYR) was projected to degrade into seasonally frozen ground(SFG) during the past four decades; furthermore, the areal average ALT increased by 3.47 cm/yr, and the areal average SFD decreased by 0.93 cm/yr from 1980 to 2018. Accordingly, the growing season Normalized Difference Vegetation Index(NDVI) presented an increasing trend of 0.002/10 yr, and the increase rate and proportion of areas with NDVI increase were largest in the transition zone where PF degraded to SFG(the PF to SFG zone). A correlation analysis indicated that variations in ALT and SFD in the SRYR were significantly correlated with increases of NDVI in the growing season. However, a rapid decrease in SFD(-1.4 cm/10 yr) could have reduced the soil moisture and, thus, decreased the NDVI. The NDVI for most vegetation types exhibited a significant positive correlation with ALT and a negative correlation with SFD. However, the steppe NDVI exhibited a significant negative correlation with the SFD in the PF to SFG zone but a positive correlation in the SFG zone, which was mainly limited by water condition because of different change rates of the SFD.     

济南市历城区典型土壤类型N、P、K养分元素的有效态分布特征

本文选择济南市历城区典型土壤中N、P、K3种养分元素进行化学测试分析,对该地区的浅层土壤元素有效态地球化学背景值及在不同类型土壤中的分布特征进行研究.研究结果表明:该地区土壤质量较好,元素有效量与全量总体排序一致,不同元素的有效度相差十分悬殊.5种土壤类型的元素有效度具有一定差异性,潮褐土、潮土中N、P、K元素的有效量...