双孢蘑菇覆土层有益微生物消长规律   总被引：1，自引：0，他引：1  

杜爱玲  王进涛  陈立国  杨新美 《食用菌学报》2001,8(2):50-52

将土样制备成稀释液，采用平板涂布培养法，分析双孢蘑菇覆土期、充分发菌期，原基形成期、采收前和采收后2d5个时期土样中几种有益微生物和消长规律。结果表明，原基表成前和采收后，采白色和采收后2d5下时期土样中几种有益微生物的消化规律。结果表明，原其开前和采收后，采白色孢杆菌(Bacillus)、固氮苗（Azotobacter)和假单胞杆菌（Pseudomonas)数量增加；链霉菌（Streptomyces)数量增减比较平缓，而土灰色芽孢杆菌的数量一直呈下降趋势。  相似文献   

Effects of 'Agri-SC' soil conditioner on soil structure and erodibility: some further observations     

M.A. Fullen  A.M. Tye  K.E. Cookson 《Soil Use and Management》1995,11(4):183-185

Abstract. In field and laboratory experiments the conditioner‘Agri-SC’has shown improvements in the structure of loamy sand soils in east Shropshire, UK. It resulted in statistically significant decreases in soil bulk density values and increases in soil porosity and aggregate stability. Further experiments are in progress on both loamy sand and silt loam soils.  相似文献   

菲律宾以稻为基础的种植制度生态学评价 Ⅰ.各类种植方式的养分平衡     

赵强基 Garr.  DD 《作物学报》1993,19(5):402-411

在菲律宾的雨养旱地、雨养低地和灌溉田种植制度研究基点上,分别对各种农民和拟推广的实验种植方式,进行了生物量及其组成、作物分器官的 C、N、P、K 含量与分布比率、作物残茬燃烧后 C、N、P、K 损失测定。从添加与取走两个方面,分三种添加与取走情况,计算了土壤N、P、K 的部分养分平衡与有机质平衡。结果显示:在当地施肥水平下,即使归还全部残茬,很难维持 N、P、K 的养分平衡,但能较好满足土壤有机质平衡。为维持土壤有机质的年平衡,雨养低地和雨养旱地需分别归还1400和1900公斤生物物质/公顷.年。并对当地维持养分平衡的途径作了分析与探讨。  相似文献   

北京中山地区非石灰性土壤发生分类的研究   总被引：4，自引：4，他引：0  

向师庆  张凤荣 《北京林业大学学报》1992,14(1):27-33

利用剖面形态、微形态、理化分析、粘粘x衍射分析等结果,对北京中山地区土壤的发生过程和分类问题进行了研究。首次提出尘暴降尘物质对土壤发生过程的滞缓作用。若土壤分类上采用pH(KCI),北京中山地区非石灰性土壤应属于暗棕壤。在土壤分类特征上,为在山地普遍应用中避免估算和推测造成混乱,建议采用反映该地区水分和温度状况的植被。  相似文献   

不同稳定剂对胭脂萝卜红色素稳定性的影响     

芮春梅  李成琼  司军  宋洪元  任雪松  李利军 《勤云标准版测试》2006,(12)

天然胭脂萝卜红色素属于花青素类化合物,性质不稳定。笔者以新鲜胭脂萝卜(Raphnussativuscv.)肉质根为原料,提取胭脂萝卜红色素,选择常用的5种稳定剂对其稳定性进行研究,从而确定出最佳的稳定剂及其用量。研究结果发现0.03%维生素C、0.03%谷氨酸、0.03%柠檬酸能明显地延缓其颜色变化,0.03%维生素C 0.03%柠檬酸的组合对该色素的稳定效果最佳;进一步研究确定维生素C和柠檬酸的最佳用量分别为0.04%和0.08%。  相似文献   

Evaluation of a combined penetrometer for simultaneous measurement of penetration resistance and soil water content     

Yurui Sun  Peter Schulze Lammers  Daokun Ma 《植物养料与土壤学杂志》2004,167(6):745-751

A combined penetrometer is an appropriate tool to measure the soil cone resistance and the water‐content profile. As a relatively new technique, a combined capacitance‐penetrometer for the simultaneous measurement of cone index and soil water content was developed at the Department of Agricultural Engineering of Bonn University in 2002. The objective of this study was the evaluation of the effectiveness and applicability of the innovated penetrometer with a focus on three aspects: (1) A capacitance sensor with two electrode configurations was calibrated for silt loam, sandy loam, and sand. The calibration results show that both electrode configurations have sufficient water‐content sensitivity, but soil‐specific calibrations seem necessary. (2) Under laboratory conditions, the dynamic resolution and response of the capacitance‐penetrometer were validated, and its radius of influence was determined. (3) The field measurement results demonstrate that this measurement technique can be used to improve the interpretation quality of soil cone index data.  相似文献   

An evaluation of the pesera soil erosion model and its application to a case study in Zakynthos, Greece     

M. Tsara  C. Kosmas  M.J. Kirkby  D. Kosma  N. Yassoglou 《Soil Use and Management》2005,21(4):377-385

Abstract. The Pan‐European Soil Erosion Risk Assessment (pesera ) model was evaluated using existing soil erosion data collected under various types of climate, vegetation, landscape and soil conditions. The data used represent a variety of typical Mediterranean land uses such as winter wheat, vines, olives and bare, stony land prevailing in hilly areas. Using this data, the model was calibrated for sediment transport by overland flow and results compared to measured soil erosion values from runoff plots and a watershed on a monthly basis. The performance of the model was assessed statistically, showing that it can be satisfactorily used for predicting soil erosion rates under the conditions included in the study. The overall model estimate including all the available experimental data was 0.69 t ha^?1 yr^?1 with a maximum error of 1.49 t ha^?1 yr^?1. After validation, the model was applied to a small watershed (60 ha) of great ecological importance for the sea turtle Caretta caretta. For this purpose, soil and vegetation maps were compiled from all the necessary data for applying the model. The model was run for three years using daily data from an existing nearby meteorological station. The predicted and measured soil erosion rates for a 7‐month period were 0.31 t and 0.18 t, respectively. Application of the model to each mapping unit showed the over‐riding importance of land use for sediment generation under the given climatic conditions. Bare land, occupying 5.5% of the watershed area, generated up to 69% of the total sediments estimated for the watershed. It is concluded that the pesera model can be used as a regional diagnostic tool under a range of soil, topographic and climatic conditions for identifying the best land use type and vegetation cover to protect hilly areas from soil erosion. The calculated overall root mean square error for the model is 0.06 t ha^?1 yr^?1, compared to a soil erosion rate of 0.04 t ha^?1 yr^?1, which can be tolerated for protecting the area for the sea turtle.  相似文献   

沙土区薄壁连拱护岸墙试验与应用     

张玉建  沈波 《排灌机械》2005,23(6):46-49

沙土区薄壁连拱护岸墙为悬臂式支撑、薄壁连拱无底板结构，拱板中间采用无砂砼排水孔的钢筋砼肋形预制板，冲沉法施工，造价低廉；外形美观，抗倾、抗滑性能强。该墙为平原沙土区河道水土保持及修复找到了一条经济合理、施工方便、简便易行的护坡办法，具有较高的实用价值和广阔的推广使用前景。  相似文献   

台江采育场竹木混交林丰产措施试验   总被引：1，自引：0，他引：1  

陈江火  林敬德 《福建林业科技》1996,23(3):35-37

对台江林业采育场现有竹木混交林进行施肥和土壤垦复两种试验，结果表明，不同施肥处理虽有一定增产效果，但经方差分析未达到显著水平；不同土壤垦复措施的增产效果，以深翻加施肥的新竹产量最高，锄草松土居第二，单纯深翻并不理想，效果不如劈山抚育。因而，新兴竹木混交林应以调整竹林结构和护笋养竹为主，每年锄草松土即可达到材用丰产林标准，不宜盲目深翻、施肥。  相似文献   

超高产水稻产量形成的气候生态特点研究   总被引：11，自引：1，他引：10  

刘军  余铁桥 《湖南农业大学学报(自然科学版)》1996,22(4):326-332

在云南和湖南异地异季种植，研究了水稻超高产形成的相应气候生态条件，结果表明：超高产水稻具有大穗、多穗、高结实率的特点．云南试区具有日较差大、日照时数多、相对湿度低，平均温度较低的气候特点，故水稻生育期较长，同化物积累多，成穗率高，灌浆强度大．湖南试区阴雨寡照是影响产量的重要因素．  相似文献