雷州半岛南部土壤肥力综合评价及空间变异

通过测定雷州半岛南部845个耕地土壤样品pH、有机质、全氮、有效磷、速效钾、碱解氮的含量,采用层次分析法确定各肥力评价指标权重,应用模糊数学法对该区域耕地土壤肥力进行综合评价,并利用ArcGIS 9.2软件对土壤肥力空间变异进行分析.结果表明:雷州半岛南部土壤有机质、全氮、有效磷、速效钾、碱解氮平均值分别为26.18 g/kg、1.48 g/kg 、34.63 mg/kg、158.57 mg/kg、133.17 mg/kg;土壤速效磷的变异系数最高,为103.14%,属强变异性,有机质、速效钾、碱解氮、全氮的变异系数属中等变异性,pH值的变异系数最小.土壤肥力总体水平处于中等偏低;从空间分布来看,土壤肥力中部高,东北、西南部相对较低     

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。     

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。     

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。     

日照茶树种植区典型茶园的土壤肥力状况评价

通过野外采样和室内测定,以日照茶树种植区3个典型茶园为研究对象,每个茶园分别取鸠坑、黄山群体、福鼎大白各3个品种,最终取得9种茶样生长地的土样,研究分析土样的pH,有机质,全N,P,K,有效N,P,K等指标的土壤养分含量状况,并以此为评价指标,运用模糊综合评判法,对3个茶园的土壤肥力质量进行了综合评价。结果表明,茶园肥力综合水平为北垛春>碧波山庄>北叶青;茶园土壤总体上,pH值较适中,有机质含量很缺乏,全N含量偏低,全P含量中等,全K含量较高,有效N含量很缺乏,有效P含量非常丰富,有效K含量中等,并据此提出了关于该地区3个典型茶园今后合理施肥的一些建议。     

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。     

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。     

桂林市周边采石场闭坑后土壤生化响应研究

文章采用时空替代法对桂林市周边5个不同闭坑时间采石场的土壤进行了研究,分析了不同闭坑年限土壤呼吸、土壤微生物量碳和土壤理化性质的变化及三者之间的关系。研究结果表明:随着闭坑年限的增加,土壤呼吸呈上升趋势,土壤微生物量碳呈先上升再下降后平稳上升趋势,土壤p H值趋于稳定,土壤容重呈下降趋势,土壤有机质、土壤全氮呈上升趋势,土壤速效钾呈先下降后上升趋势;在土壤呼吸、土壤微生物量碳和土壤理化性质的关系中,土壤呼吸与土壤理化性质均无显著相关性,土壤微生物量碳与土壤容重、有机质和全氮含量具有显著正相关。     

攀西钒钛磁铁矿山排土场生态修复调查研究:以四川攀枝花市红格矿山为例

矿区排土场生态修复是近年来矿山生态修复的难点与重点,为了有效提升攀西地区钒钛磁铁矿区的排土场生态修复效果,以四川攀枝花市红格钒钛磁铁矿山的四大排土场为例,设置样方对植被和土壤进行调查分析.结果表明:①各排土场呈现出被子植物恢复较好,略缺少蕨类植物和裸子植物,排土场平台植被盖度和物种丰富度均高于边坡;②当地的先锋植物为木豆CajaＧnuscajan、饿蚂蝗Desmodium multiflorum、白背枫Buddlejaasiatica、戟叶酸模Rumexhastatus４种灌木和狗牙根CynodondacＧtylon、紫马唐Digitariaviolascens、毛臂形草Brachiariavillosa、羽芒菊 Tridaxprocumbens、荩草 Arthraxonhispidus、白酒草Conyzajaponica、狗尾草Setariaviridis、黄茅 Heteropogoncontortus、鬼针草Bidenspilosa９种草本;③各排土场土壤偏关性分析表明提高土壤pH 值能提高土壤中碱解氮的质量分数;④速效磷、TP、有机质在不同土样之间存在相对较大的离散程度,TN 含量分布较集中,土样的 TN、速效钾、速效磷、有机质、碱解氮均处于较低水平或极低水平.基于此,攀西钒钛磁铁矿区排土场应根据上述先锋植物采取相应的配置模式,提升覆土厚度,可以添加碳酸钙、熟石灰等农用石灰性物质来中和土壤的酸性条件,并通过添加化学肥料改良土壤肥力,从而提升修复效果.      

山东省茌平县土壤元素地球化学特征与质量评价

以茌平县土壤为研究对象,通过系统的地球化学调查,获取了土壤20余项指标含量数据;在此基础上计算了茌平县土壤中背景值和基准值等系列地球化学参数,圈定地球化学异常区,评价了土壤养分和环境地球化学等级、土壤质量地球化学综合等级。结果表明,与山东省土壤背景值平均值相比,茌平县土壤中K、Mn、Pb、V、Mo、I等元素偏低,而有机质、As、Cd、Hg、B等元素偏高。调查区7类异常区域均有分布;土壤质量综合评价以优质等级为主,约占全区面积的73.96%,良好等级约占全区面积的24.67%。     

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.     

Effects of biofertilizers and super absorbent polymers on plant growth and soil fertility in the arid mining area of Inner Mongolia,China

A pot experiment was conducted in the Institute of Tianlong Ecology of Baotou City in Inner Mongolia, China, to investigate the effects of the application of biofertilizers and super absorbent polymers (SAP) on plant growth and soil improvement in arid mining area soil. Two typical species, namely, Syringa oblata Lindl. (SO) and Medicago sativa L. (MS), were present in the Bayan Obo mining area and used as representatives of shrubs and herbaceous plants in the pot experiment. (1) Biofertilizers and SAP significantly increased the tree height, the ground diameter of SO, and the total biomass of MS and improved the soil fertility of the mining area, especially its biological fertility, compared with those of the control group (CK). The application of biofertilizers and SAP decreased the mining soil pH and significantly increased available nitrogen, available phosphorus, available potassium, and soil organic matter. (2) After 180 days of growth, the microbial population (bacteria, fungi, and actinomycetes) and soil microbial biomass carbon and nitrogen significantly increased. Microbial ratios C: N significantly decreased compared with those of CK. (3) T5 and T6 treatments with the following dosages might be the optimum selection for the improvement of the studied mining area soil: 20 g SAP + 15 g biofertilizers (SO), 100 g/m² SAP + 150 g biofertilizers (MS); 20 g SAP + 30 g biofertilizers (SO), and 100 g/m² SAP + 200 g biofertilizers (MS). This study provided a promising reference for conducting future field studies and the local vegetation restoration.     

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.     

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.     

A novel model to assess soil productivity in the dry-hot valleys of China

Accurate evaluation of soil productivity has been a long-standing challenge. Although numerous models for productivity assessment exist, most are cumbersome to use and require substantial parameter inputs. We developed a new empirical soil productivity model based on field investigations of soil erosion, soil physicochemical properties, and crop yields in the dry-hot valleys (DHVs) in China. We found that soil pH, and organic matter and available potassium contents significantly affected crop yields under eroded conditions of the DHVs. Moreover, available potassium content was the key factor affecting soil productivity. We then modified an existing soil productivity model by adding the following parameters: contents of effective water, potassium, organic matter, and clay, soil pH, and root weighting factor. The modified soil productivity model explained 63.5% of the crop yield. We concluded that the new model was simple, realistic, and exhibited strong predictability. In addition to providing an accurate assessment of soil productivity, our model could potentially be applied as a soil module in comprehensive crop models.     

高密市耕地表层土壤营养元素有效态地球化学特征

通过对高密市耕地表层土壤进行调查,获得了N,P,K,Cu,Zn,Mo,B等7种营养元素全量和有效量,以及pH值和有机质数据,采用数据统计、相关性分析、对比分析等方法,研究有效态地球化学特征及其受控因素。结果表明,元素全量对有效态具有直观制约影响,元素全量与其有效量均呈正相关,与P,K,Cu,Zn有效度呈正相关,表现为协同作用的有N全量对P有效量,P全量对K,Cu,Zn有效量,Cu全量对P,Zn有效量,Zn全量对P,Cu有效量,P全量对K有效量;酸性土壤能够提高N,P,Cu,Zn,Mo元素的生物有效性,碱性土壤能够提高B元素的生物有效性;有机质能够影响土壤营养元素活化,对有效量有一定的促进作用,有机质增加可以不同程度提高K,Zn,B元素的有效度,但会降低N元素的有效度;不同土壤类型的土壤理化性质有所不同,如土壤pH值和有机质的差异,是影响土壤营养元素有效态的重要因素。