盐化潮土不同农田土壤养分和土壤酶活性研究

对天津近郊盐化潮土不同农田中土壤脲酶、蛋白酶、转化酶、碱性磷酸酶活性和土壤养分进行了分析研究。结果表明,不同农田中土壤养分含量和酶活性存在显著差异。农田土壤养分和土壤酶活性不仅具有垂直分布的规律而且土壤酶活性和土壤养分显著相关。主成分分析提取了转化酶综合因子和全氮因子。转化酶可作为盐化潮土不同农田中土壤养分的肥力指标。     

三种钠盐对石灰性土壤盐化特性的影响

以甘肃省秦安县果园石灰性土壤为研究对象,利用室内模拟的方法,探讨了三种钠盐(NaHCO3、NaAc和NaCl)对石灰性土壤盐化特性(全盐、pH、水溶性Na+和交换性Na+)的影响.结果表明,在三种钠盐中,NaHCO3和NaAc对石灰性土壤盐化特性相似,而NaCl对石灰性土壤盐化特性与其不同.土壤全盐、水溶性钠和交换性钠随三种钠盐加入量的增加而增加,土壤pH值随着NaCl加入量的增加而逐渐减小,随着NaHCO3和NaAc加入量的增加而逐渐增大.     

农业生态环境敏感性地域分布及整治对策

农业生态环境日益恶化,越来越引起社会各界的关注。有效的综合整治农业生态环境,已经成为科学界面临的一个挑战。中国农业主要面临的生态环境问题是水土流失、盐渍化和酸雨,三种农业生态环境在空间上存在着相关性。对于三种生态环境问题,提出的控制对策如下：盐渍化的治理对策为合理用水、施肥,种植合适的耐盐作物;酸沉降治理对策为种植抗酸作物和采用化学调控方法降低降对作物的损害;水土流失使用生态恢复工程和生态重建工程进行治理。     

不同改良措施对晋北盐碱土盐碱障碍和青贮玉米氮素吸收的调控

2019-2020年，本研究以晋北大同盆地的中度盐碱地为研究对象，分析不施肥（CK）、常规施肥下添加生物质炭和CaSO₄（L）、常规施肥下添加生物质炭和CaSO₄及种植2，3，4行（LC1，LC2，LC3）绿肥等5个处理对土壤pH、土壤盐分含量、钠吸附比（Sodium adsorption ratio，SAR）以及作物氮素吸收利用的影响。研究结果表明：与对照相比，经过2年的土壤改良，各改良措施对盐碱土0～20 cm土壤pH调控显著；各改良措施对0～20 cm土壤盐分调控作用明显，LC1，LC2和LC3处理的脱盐率分别达到了41.16%，39.18%和38.88%；4种改良措施均显著降低了土壤的SAR（P<0.05），其中，CL2处理SAR降幅最大。此外，各改良措施均明显提高了青贮玉米的生物产量和氮肥利用率，尤以CL1处理的效果显著。综合分析可知，各改良措施能有效促进盐渍土降盐脱碱，改善土壤结构，且CL1处理下生物产量高，可实现生态效益和经济效益的双赢。     

Digital soil mapping to enable classification of the salt-affected soils in desert agro-ecological zones

Digital soil mapping is critical when quantifying the relationship between soil types and their associated bio-physical environments. Digital mapping of regional soils affected by salt is essential when monitoring the dynamics of soil salts and planning land development and reclamatation schemes. In this paper, an easy method for digitally mapping salt-affected soils is proposed. This method allows the construction of the quantitative lower categories of soil classification based on Chinese Soil Taxonomy by using a geostatistical method and GIS technology. The data and maps used in this study were collected during a soil survey of salt-affected desert agro-ecological zones in Karamay, Xinjiang Autonomous Region, China. The survey covers an area of 525 km² and includes 205 soil profiles. In addition, a classification and indicator system for the salt-affected soil in the region was established and 30 salt-affected soil types were identified. Three key soil classification indicators, viz. soil texture, texture stratification combination and total soil salinity, were selected to enable low-category soil classification. Furthermore, the information regarding climate, vegetation and topographic and geomorphologic features of the region was integrated into the analysis. A GIS-based regional digital soil classification map was then generated for three layers (0-30 cm, 30-60 cm, and 60-100 cm) after the observed soil salt distribution map and soil texture stratification maps were overlaid. This map would be used to draw up the strategies of the salt-affected soils improvement in desert. While compared with the conventional approaches, this new digital soil mapping method has the advantages of being prompt, quantitative, more objective, simpler and easier to update.     

吉林西部草地次生盐碱化与改良治理

本文探讨了松嫩平原草地次生盐碱化的发生原因、形成过程和治理途径。认为人类过度利用造成植被退化是草地次生盐碱化的主要原因。羊草作为羊草草地植物群落优势种,其数量指际(重要值,Important Value, Ⅳ)作为草地植被退化指标,与土壤电导率(EC)和碱化度(ESP)的函数关系分别为:;Ⅳ=50.07·0.69~(EC)((?)=—0.8499和Ⅳ=64.02·0.97~(ESP)(r=—0.7501)。表明随着土壤盐碱化程度的提高,羊草在群落中的优势度(Ⅳ)呈鱼指数形式下降。并提出了“避重就轻、先易后难、以防为主、用改结合”的治理原则和“以生物改良方法为主的治理途径”。对建立草地畜牧业优化生态模式具有一定的参考价值。     

包头市土地退化与复垦研究

本项研究划分了包头市土地退化类型，分析了土地退化原因，从而提示了土地奶穹的演变规律，提出了包头市土地退化防治对策，为全面控制土地退化，加速土地复垦，合理开发利用土地资源奠定了基础。     

辉河保护区温性草甸草原植被群落结构和碳储量对盐碱化的响应

为阐明草地盐碱化过程中草地植物群落结构及碳储量的变化,以辉河保护区内的天然草地、草地-盐碱地过渡带和盐碱地为研究对象,采用野外调查采样结合室内分析的方法进行测试研究。结果表明随着草地盐碱化加剧,植被群落结构组成趋于简单化;植被碳储量和生态系统碳储量均逐渐下降,表层土壤有机碳储量表现为过渡带>盐碱地>天然草地。植被碳储量的变化主要与地上植被类型、植被生长特性和土壤理化性质有关;表层土壤有机碳储量的变化主要是地上植被和土壤水分与不同盐碱化草地相互响应的结果,其中,pH会显著影响表层土壤有机碳储量(P<0.05);生态系统碳储量的变化受到植被更迭和土壤pH的影响。因此,温性草甸草原植被群落结构和碳储量均会受到草地盐碱化的影响。     

LAND UTILIZATION COUNTERMEASURES AND CURRENT SITUATION OF HETAO IRRIGATION REGION IN INNER MONGOLIA

<正> Hetao irrigation region is situated in the western part of Inner Mongolia. It stands bythe Yin·Shan mountain in the north, leans against the Yellow River in the south, nears theeastern side of Ulanbuhe Desert in the west and borders on Baotou in the east. It is 280kilometers in length from east to west. and 45-90 kilometers in width from north to south.     

THE ECOLOGICAL DISASTERS IN NINGXIA AND THE COUNTERMEASURES

<正> Ningxia lies in the midland of China, along the upper and middle of the Yellow River.The south of the region belongs to the Loess Plateau and the north of it is Part of theMongolian plateau. The main feature of the climate in the whole region is dry or half dry.The ecological enviroment is in a very delicate state and human activities have made itworse. The severe consequences are widely-spread various types of ecological disasters. All