内蒙古几种野生牧草生态型的研究——Ⅰ华北驼绒藜

通过对2份华北驼绒藜材料农艺性状、化学成分、染色体、同功酶等各项指标的对比，确定了内蒙古哲里木盟和巴彦淖尔盟产的2种华北驼绒藜为2个地理生态型，并对其进行了评价。     

长江口海域浮游软体动物生态特征的季节变化

根据2002-2003年长江口28°00′-2°00′N、122°00′-123°30′E海域4个季节的海洋调查资料,运用定量、定性方法,探讨了长江口邻近海域浮游软体动物总丰度的平面分布、季节变化、种类组成及优势种的环境适应类型。结果表明,长江口海域浮游软体动物总丰度分别为:春季64.61ind/m3,夏季191.84ind/m3,秋季59.11ind/m3,冬季1.4ind/m3。四季共出现软体动物24种,其中春季8种,夏季21种,秋季10种,冬季2种。马蹄螔螺(Limacina trochiformis)适温较低,是春季主要优势种;明螺(Atlanta peroni)作为暖水种,是夏季主要的优势种;秋季主要优势种为尖笔帽螺(Creseis acicula),适应于较高的水温;强卷螺(Agadina stimpsoniji)适温较低,是冬季的主要优势种。春季浮游软体动物大多聚集在苏北沿岸流和长江径流交汇处或偏沿岸流一侧,夏季在河口咸淡水水团内,秋季的高丰度则主要出现在台湾暖流和长江径流交汇偏暖水的一侧,冬季出现种类较少,低温是其最主要的因素。浮游软体动物作为一种偏大洋性的种类,在外海的数量和种类分布要远高于近海。     

猪粪有机肥施用下两种生态型粗齿冷水花磷积累特征变化

猪粪的不合理施用导致土壤中磷素大量积累,引起一系列环境问题。研究磷富集植物在猪粪条件下的磷积累变化特征,可以为提取土壤中过量的磷提供理论依据。以矿山生态型粗齿冷水花为研究对象,非矿山生态型为对照,设置猪粪有机肥用量为50 g/kg,开展土培盆栽试验。结果表明:1)猪粪有机肥施用下,两种生态型粗齿冷水花地上部和整株生物量随生长时期的延长均在13周最高,且矿山生态型显著高于非矿山生态型(P<0.05),分别为非矿山生态型的1.43~2.26倍和1.41~2.20倍。2)粗齿冷水花地上部和整株阶段性磷积累速率均在9~11周最大。矿山生态型粗齿冷水花地上部和整株磷积累量均显著高于非矿山生态型(P<0.05),13周时其地上部和整株磷积累量分别达105.21和119.50 mg/株。3)猪粪有机肥的施用提高了土壤有效磷含量、酸性磷酸酶和植酸酶活性。随生长时期的延长,粗齿冷水花根际酸性磷酸酶和植酸酶活性均在11周最高,矿山生态型根际植酸酶活性显著高于非矿山生态型。猪粪有机肥施用下,矿山生态型粗齿冷水花生长状况和磷积累能力均强于非矿山生态型,其根际较高的酸性磷酸酶和植酸酶活性提高了土壤中磷素的生物有效性,促进了矿山生态型对磷的吸收积累。     

Endophyte Effects on Nutrient Acquisition in Tall Fescue Grown in Andisols

ABSTRACT

An experiment was conducted to evaluate the effect of endophyte Neotyphodium coenophialum (Morgan-Jones and Gams) Glenn, Bacon, and Hanlin on the mineral content of tall fescue (Lolium arundinaceum Schreb., SJ Darbyshire) ecotypes (Fukaura, Koiwai, and Showa) grown on two Andisols (Black Andisol and Red Andisol) with different fertilities. Black Andisol, with a naturally low content of phosphorus, was high in other nutrients, while Red Andisol, with a naturally high content of phosphorus, was low in other nutrients. Shoot dry weight was significantly higher in endophyte-infected (E+) than endophyte-free (E?) plants grown in Black Andisol. On the other hand, in Red Andisol, only Fukaura showed higher shoot dry matter production in E+ plants as compared to E- plants. In general, greater concentrations of phosphorus and manganese were found in endophyte-infected (E+) plants than non-infected (E?) plants. Accumulation of all nutrients in E+ plants was remarkably higher than in E? plants. Excluding the plant ecotype effect, the nutrient concentration and accumulation pattern for plants in the two soils was different in E+ and E? plants. Plants growing in Black Andisol had greater concentrations of phosphorus (P), copper (Cu), and zinc (Zn) in E+ plants than those of E? plants whereas for plants in Red Andisol the reverse was true. Significantly higher concentration of manganese (Mn) was found in E+ plants irrespective of soils. Regardless of endophyte and ecotypes, plants grown in Black Andisol showed significantly higher values for both nutrient concentration and accumulation than those in Red Andisol. Apart from the plant ecotype Showa, all other ecotypes had the greatest accumulation and concentration of phosphorus in E+ plants. In two types of soil and among the three plant ecotypes, endophyte infection had different effects on nutrients acquisition. Giving emphasis on nutrient accumulation, endophyte played an overall negative role on plants grown in Red Andisol. There may be a metabolic cost of harboring endophytes offset its benefit in Red Andisol. Since the same species of endophyte infected all three ecotypes, our results show that the host/endophyte interaction depends on plant ecotype as well as the ability of the soil to supply nutrients.     

Foliar applied harpin effects on fruit quality of peppers

Abstract

During the past century, changes in cropping systems have led to selective pressure on weed flora. The number of competitive species with decreased susceptibility to herbicides has increased, at the cost of more susceptible species. For a long period, the economically important perennial weed species Cirsium arvense (L.) Scop. and Sonchus arvensis L. have mainly been controlled by the herbicide MCPA (phenoxy-acetic acid), which stimulates the weed plant to abnormal growth. However, it has been reported from Sweden, Great Britain, Hungary and North America that C. arvense has become less susceptible to MCPA since the 1950s. Therefore, two greenhouse experiments were performed at Uppsala, Sweden with clones of C. arvense and S. arvensis. The purpose was to study whether ecotypes (clones) from high input farmland, where herbicides had been used intensively and regularly for a long time, were less susceptible to herbicide (MCPA) treatment than ecotypes from low input farmland. Sixty clones of C. arvense and 36 clones of S. arvensis were treated with nine different doses of MCPA. The results supported the suggestion that a shift towards less MCPA-susceptible ecotypes of C. arvense had occurred on high input farmland. Clone material from such farmland had, on average, significantly higher dry matter content after herbicide treatment than ecotypes from low input farmland. Similar decrease in susceptibility was not detected for S. arvensis. This was probably due to S. arvensis generally being less susceptible to MCPA than C. arvense. Sonchus arvensis has therefore being exposed to a lower selection pressure than C. arvense.     

刺槐林下植被的水分生态型和生活型谱特征

为探讨刺槐生长对当地地带性植被生长的影响,2006年8—9月对位于黄土高原森林草原区安塞县纸坊沟流域不同林龄的刺槐林下植被进行群落调查,分析林下植被的物种组成、水分生态型和生活型谱特征。刺槐林下植被的演替具有与撂荒地自然演替类似的进程,与撂荒演替不同的是,阳生性的白羊草在刺槐林下始终未形成优势种群。尽管刺槐生长过度消耗土壤水分,土壤旱化趋势明显,植被却由旱生型向中生型转变,从物种组成的角度看并没有明显的旱生倾向。随着刺槐林龄的增加,林下植被逐渐形成2个明显的层片,即以多年生半灌木蒿类为主的地上芽植物层片和以多年生丛生性禾草为主的地面芽植物层片。结果表明,刺槐的生长并没有从根本上改变林下植被的自然演替进程,选择刺槐作为本区域植被恢复的先锋树种是可行的。     

黄土丘陵沟壑区坡沟植被生态序列研究

植被生态序列是小地形对植被空间分布影响的反映。采用样线法,对安塞纸坊沟支沟拐沟中南北向短坡面深沟谷和长坡面浅沟谷断面进行植被调查,分析其植被生态序列特征、物种组成及物种多样性。结果表明：短坡面深沟谷序列主要以灌乔木等演替后期物种为主,而长坡面浅沟谷序列则主要为草本物种;同一序列中,阴坡、沟谷地具有比阳坡、沟间地复杂的演替后期群落;序列中物种主要由菊科（Compositae）、豆科（Leguminosem）和禾本科（Gramineae）构成,生活型主要为多年生草本,生态型以旱生、中旱生为主。α多样性指数在阴坡和短坡面深沟谷序列较高,β多样性指数在地形变化活跃的沟缘线区较高。研究结果可为黄土丘陵沟壑区植被建设人工调节提供参考依据。     

农牧交错带水土保持生态建设模型分析——以小公乌素村为例

位于阴山北麓丘陵区农牧交错带的小公乌素村经过３ａ的生态农业建设已初见成效。采用柯布一道格拉斯生产函数模型,对其进行生态效益和经济效益的综合评价,为阴山北麓丘陵区大范围的生态农业建设提供经验。     

畜禽污染防治工程典型模式效益分析

案例分析能源生态型沼气工程、能源环保型沼气工程和发酵床技术的工艺类型,比较3种工程的经济效益、技术效益和环境效益。沼气工程前期投资大,但大型能源生态型沼气工程可以通过丰富再生能源获得收益,能源环保型沼气工程相对于能源生态型沼气工程投资大、收益小,发酵床技术可以实现畜禽粪便"零排放",但菌剂费用造成高额运行费用。建议加强大型生态型沼气工程发展,增强发酵床菌剂的研究以降低发酵床运行成本,推动有机肥市场的有效运行。     

中国北方生态型笋形茎用芥‘鲁笋芥1号’

原产四川的芥菜种笋子芥变种引种到北方后因先期抽薹严重，不能形成产品器官，“鲁笋芥1号”是根据植物对光周期反应原理，新育成的北方生态型笋形茎用芥新品种，早熟、高产、质优、抗病，可秋春两作，笋茎产量30－40t/hm^2，可食叶片15－20t/hm^2。