Native Seed Collection and Use in Arid Land Reclamation: A Low-Tech Approach

Loss of vegetation production in arid lands has been difficult to remediate and has signifi- cant economic impacts on human populations. Restoration efforts based on non-local materials and large-scale mechanization have not been capable of efficiently reversing the trend of environmental degradation. The use of traditional knowledge and simplified methods of seed harvesting, storing, marketing and soil preparation have proven that regeneration of native species and efficient land reclamation is possible in areas that have traditionally been considered degraded beyond redemption. This paper describes a method of land reclamation that combines tradition and simple mechanics that can be applied in all arid areas that face desertification. Because the work builds on cultural practices long used in non-industrialized societies, it is particularly adapted to rural areas. The methods described have the potential to open new low-tech economic opportunities to all segments of local non-urban populations while combating desertification and creating a more ecologically sound environment.     

Grazing effects on sustainable semiarid rangeiands in Patagonia: The state and dynamics of the soil seed bank

The composition of the germinable seed bank was studied in four vegetation states of the Festuca pallescens grasslands in semiarid Patagonia during four years. The aim of this study was to test whether above-ground vegetation states resulting from grazing exclusion or different combinations of grazing and topography are reflected in different states of the germinable seed bank. The size of the total and dicot germinable seed bank was positively related to the total cover in each state. Dicots dominated all germinable seed bank states. Carex patagonica increased its cover as well as its germinable seed bank under grazing disturbance. Grazing did not reduce the germinable seed bank of perennial grasses in uplands where the grazing pressure is lower as compared with slopes. In slopes the germinable seed bank of perennial grasses was significantly reduced by grazing. A reduction of the length of the grazing period in late spring increases the germinable seed bank of perennial grasses both in upland and slope. These results are interpreted in the frame of a model of management techniques where grazing exclusion during late spring and late summer increases the seed bank of the perennial grasses and promotes their establishment in uplands. The artificial addition of seeds of perennial grasses and the manipulation of the soil surface in order to increase "safe sites" appear as management alternatives that deserve further evaluation to improve plant reestablishment in slopes.     

炼厂脱盐脱钙废水处理工艺

原油中的钙盐主要存在于石油胶质和沥青质中。在原油加工过程中,有机钙盐因分解形成钙沉淀物而影响正常生产。对于原油中钙的脱除,目前应用最广泛的是螯合沉淀脱钙技术。炼厂脱盐脱钙废水中的钙、磷、石油胶质会对污水处理场造成不良影响,因而必须对脱盐脱钙废水进行预处理。预处理工艺包括物理和物理化学手段、生物处理工艺、化学氧化处理技术。技术可行性分析表明,可采用AOP高级氧化技术与生物处理相结合的工艺对脱盐脱钙废水进行预处理。     

黄山自然风景保护区种子植物多样性的开发利用

黄山自然风景保护区自然条件优越,森林植被垂直分布明显,种子植物丰富,有134科655属1483种,其中国家重点保护植物有31种.由于旅游的发展,种子植物多样性受到威胁,应加强种子植物的保护.     

利用苦瓜子衣制备食用色素的研究

对苦瓜子衣色素的提取工艺及安全性进行了研究,确定了最佳提取工艺条件为:用乙醚作提取剂,提取剂用量为1∶40g/ml,提取时间为20min,提取温度为20℃,提取次数为2次。毒性试验表明:该色素的毒性很低,主要有毒元素的含量为Pb<2.0ppm、As<2.0ppm、Hg<0.01ppm。     

土壤种子库植物种类组成与土壤采集地植被的关系

土壤种子库作为区域自然植被恢复的途径之一,在实际应用之前有许多课题需要研究,土壤种子库出芽植物组成与土壤采集地自然植被的关系就是一个需要弄清的问题。文章从土壤种子库的生态学意义出发,首次对森林表土作为城市自然植被恢复绿化手段的可能性进行了探讨。试验材料取自日本大阪府箕面市大阪国际文化公园都市建设地,选取面积为20m×20m的栓皮栎Quercusvariabilis群落,采集林下5cm厚森林表土;试验场地设在大阪府枚方市山田池公园的一隅荒地,共设置4个试验区,每个试验区7个试验处理,计28个试验小区。研究结果表明:土壤种子库植物种类组成与表土采集地的植被关联性较低,但与种子散布型关系密切;表土的不同铺撒厚度在木本植物出现的种类、出芽个体数、生存个体数等方面都表现出明显的差异性。     

几种生物学指标与生物强化系统降解效率的关系

针对炼油废水生物强化处理系统中有时存在的不稳定造成排水超标的问题,研究了SBR反应器中采用生物强化技术,其细菌数量、脱氢酶、邻苯二酚1,2-双加氧酶(C12O)和邻苯二酚2,3-双加氧酶(C23O)等关键生物学指标与污染物去除效率的综合对应关系,并运用ERIC-PCR技术研究了运行前后处理系统内微生物群落的变化.结果表明,投加菌剂的生物强化处理系统提高了细菌数量和酶活,使处理效率明显提高.生物强化系统中细菌数量及C23O酶活与污染物去除效率呈正相关关系,且微生物群落结构十分稳定.C12O为一种诱导酶,其酶     

Composting MSW and sewage sludge with effective complex microorganisms

ＩｎｔｒｏｄｕｃｔｉｏｎＣｏｍｐｏｓｔｉｎｇｉｓｕｓｅｄａｓａｔｒｅａｔｍｅｎｔｍｅｔｈｏｄｏｆｔｈｅｍｕｎｉｃｉｐａｌｓｏｌｉｄｗａｓｔｅ (ＭＳＷ)ａｎｄｓｅｗａｇｅｓｌｕｄｇｅ ,ａｎｄｔｈｅｐｒｏｃｅｓｓｙｉｅｌｄｓａｓｔａｂｌｅ,ｐｒｏｆｉｔａｂｌｅｐｒｏｄｕｃｔｗｈｉｃｈｉｓｓｕｉｔａｂｌｅｆｏｒｕｓｅａｓａｓｏｉｌｃｏｎｄｉｔｉｏｎｅｒａｎｄｗｈｉｃｈａｌｓｏｈａｓａｃｅｒｔａｉｎｎｕｔｒｉｅｎｔｖａｌｕｅ (Ｂｉｅｙ ,2 0 0 0 ) .Ｇｅｎｅｒａｌｌｙ ,ｃｏｍｐｏｓｔｉｎｇｉｓａｎａｃｃｅｌ…     

水稻籽实中蛋白质-Cd、Pb结合体及其稳定性

通过凝脱层析方法，对水稻籽实中的蛋白质－Cd,Pb结合形态特征及其稳定性进行了研究。结果表明；水稻籽实TrisHCl提取液经SephadexG-75分 离，洗脱液得到3个紫外吸收峰，在第1、3峰处出现了Cd、Pb浓度峰，其蛋白质－Cd、Pb结合体的表观分子量为54.5KD和5.5KD。在蒸煮加热处理后，水稻籽实中蛋白质－Cd、Pb结合体发生变性，使分子量为54.5KD的蛋白质－Cd,Pb结合体完全破坏，分子量为5.5KD的结合体也部分地被破坏，与蛋白质结合的Cd ,Pb被释放出来。胃蛋白酶和胰蛋白酶消化处理后，也能够破坏蛋白质－Cd,Pb结合体的形态，洗脱液中Cd,Pb的浓度分布也发生了变化，在第1、3紫外吸收峰处的Cd、Pb浓度也明显降低。另外，在第3峰以后的洗脱液中也检测到Cd、Pb的浓度。     

转基因植物入侵性评价指标初探

从生态学 (种子水平和成体水平 )和生理生化 (酶表达、蛋白检测、光合能力等 )层次 ,探讨转基因植物 (GMP)可能形成入侵性的一些特性 ,尝试建立GMP入侵性的评价指标体系 ,为进行转基因植物的安全性评价提供借鉴。