不同农田有机物料组合对物料分解过程的影响

试验采用凋落袋法来研究农田有机物料混合后的分解状况。选取风干的水稻秸秆、花生秸秆和猪粪三种有机物料,设置九种处理,田间分解30 d、90 d、180 d和360 d四个阶段取样,测定物料分解率、基本养分及pH值等指标。结果显示,不同农田有机物料混合分解时,SZ、HZ、7S3H及3S7H混合处理的分解率均表现出正交互作用效应,而SHZ及SH混合处理均表现出负交互作用效应。农田有机物料混合可以调节物料的营养结构,优化不同营养物质搭配比例,使调节后物料促进微生物活性的增强,对碳源利用更加彻底,充分吸收周围可被利用的营养物质(N、P、K),有利于营养物质的富集。物料组合对pH值的影响均表现出正交互作用效应。     

义马煤矿矸石山植被恢复土地适宜性评价

以义马煤矿矸石山为研究对象,选取pH值、土层厚度、有机质、田间持水量、稳渗率、容重、总孔隙度和植被盖度8个评价指标,采用主成分分析法确定权重,采用加权和法计算土壤质量综合指数值(SQI),对不同排矸年限和有无人工干预的矸石山进行植被恢复土地适宜性评价。结果表明:随排矸年限的增加,土壤的植被恢复适宜性增加;人工种植具有改良土壤作用的树种(如刺槐)能够显著加快矸石山土壤改良过程,植被恢复适宜性显著好于没有人工干预的煤矸石山;边坡不稳定,植物难以定居,植被恢复适宜性最差,应采取措施稳固边坡。     

不同种植年限设施菜地土壤微生物量和群落结构的差异

【目的】研究不同种植年限设施菜地土壤微生物量和群落多样性变化规律,探索高度集约利用下土壤质量退化的根本原因和机理,为设施菜地土壤可持续利用提供理论参考。【方法】采集江苏省常熟市由稻麦轮作农田转变为设施菜地种植3 a、6 a和10 a等3个不同年限0—20 cm表层土壤,以周围种植水稻/小麦的农田土壤作为参照,分别测定土壤理化性质、微生物量和微生物群落多样性等指标。【结果】由稻麦轮作农田转变为设施菜地种植3 a的土壤微生物活性较强,养分含量较高;种植6 a后微生物活性明显降低,速效养分含量积累。种植年限从3 a到10 a,速效氮含量升高66.1%,速效磷含量升高97.2%。种植3 a以内p H接近中性,而种植6 a以上p H降低至酸性。土壤微生物量碳和微生物商在种植3 a均最高,种植6 a和10 a后显著降低。微生物群落的碳源利用指纹(BIOLOG)分析表明,种植3 a平均吸光值(AWCD)和微生物多样性指数(Shannon、Simpson和Mc Intosh)均最大,对碳源的利用能力最强,种植6 a和10 a明显降低,其中AWCD和Shannon指数分别比种植3 a降低了96.1%、15.4%和89.7%、17.6%。磷脂脂肪酸(PLFA)分析表明,种植3 a PLFA总量及细菌、真菌、放线菌PLFA含量均最大,而种植6 a和10 a以上指标均明显降低,其中,种植10 a土壤的PLFA总量及细菌、真菌、放线菌PLFA含量分别比种植3 a降低27.4%、21.8%、42.7%、49.4%(P0.05)。【结论】随着设施菜地种植年限增加,土壤微生物量和群落结构发生了明显变化,设施菜地种植3 a土壤微生物活性和群落结构稳定性明显增强,而种植6 a以上土壤微生物活性和群落结构稳定性明显降低,土壤生物质量显著退化。     

江苏省水土保持功能的重要性评价

[目的]对江苏省水土保持功能重要性进行评价,为水土保持功能区划和水土保持治理措施布局提供重要依据。[方法]根据江苏省自然环境、社会经济、土地利用和水土流失特征,选取土壤保持、农田防护、水质维护和人居环境维护4项水土保持功能进行重要性及其空间分布特征的评价,并进行综合评价。[结果]江苏省水土保持功能重要性程度较高,极重要区和中等重要区分别占全省总面积的42.10%和46.44%;苏北地区主要水土保持功能是土壤保持和农田防护,苏中地区主要水土保持功能是农田防护和水质维护,苏南地区主要水土保持功能是水质维护和人居环境维护。[结论]评价结果揭示了江苏省水土保持功能重要性等级及其空间分布特征。     

不同有机物料组合对土壤养分和生化性状的影响

【Objective】 The objective of this study is to explore the effects of single type of organic matter and their combinations with various proportions of different organic materials on soil properties. The results would also provide a scientific basis and practical guidance to optimal utilization of agricultural organic wastes and achieve the aim of optimal configuration and agricultural sustainability regarding to soil quality. 【Method】 In this study, three organic materials were used, including rice straw, peanut straw and pig manure. Based on the mass ratio, the single type of organic matter only, the combination of both (rice straw and peanut straw mixing at the ratio of 7﹕3 and 3﹕7, respectively) and three ones (1﹕1). All single and mixture treatments were amended with 1% organic matters of the soil mass and cultivated for 90 days. Thereafter, soil nutrient and biochemical properties were measured. 【Result】 The results showed that different organic materials had a significant impact on soil nutrients and biochemical characteristics. Overall, mixtures of different organic materials were more effective than only single one for improving soil properties measured. The mixture treatments on soil nutrient availability showed additional effects, i.e. the nutrient release derived from mixtures were more than weighted average values of two and three materials. The additional effects of the mixtures on the activities of urease and invertase were not significant, for example, the increased effects of SZ, SHZ and 3S7H mixtures on invertase were 1.46%, 0.18% and 5.97%, respectively. Carbon mineralization rate of the mixture treatments had significant negative additional effects with the treatments of SH, SZ and 3S7H showed 9.91%, 23.54% and 22.95% lower than the weighted average values, respectively. And the corresponding decreased effects for the CO2-C production rate were 24.56%, 16.47% and 18.18%, respectively. BIOLOG analysis showed that AWCD value and carbon utilization potential of the treatments S and 7S3H were the highest among all treatments. The metabolic quotients (qCO2) in the S and 7S3H treatments were higher than those of other treatments. The materials combination of nutrient release and microbial biomass carbon and nitrogen had stronger positive addition. The materials combination of mineralization of organic carbon and qCO2 had stronger negative addition. 【Conclusion】 Results showed that mixing organic materials could improve soil nutrient contents enhance as well as soil biochemical activity. Compared to only one type of organic matter, materials mixture could provide more resources and favorable habitat for soil biological development, leading to acceleration of decomposition and nutrient release and finally improvement of soil fertility.     

核桃组织培养研究综述

综述了影响核桃组培的主要因子，不同的核桃品种、培养基、激素和培养条件等都会影响核桃的组织培养。并对组织培养过程中存在的褐化、污染、适宜培养基选择和外植体选择等问题及解决办法进行了讨论，对核桃组织培养的应用前景进行了展望。