梯级稻田主要营养元素的平衡特点

通过研究梯级稻田主要营养元素的输入、输出途径，发现了丘陵梯田所存在的生态环境问题及其营养丰缺状况，为合理施肥、发挥资源潜力提出了一系列的意见和建议。     

耕地土壤中交换态钙镁铁锰铜锌相关关系研究

应用主成份分析、聚类分析和相关性分析对沈阳市郊区1994个耕地土壤样本(0-20cm)的交换态钙、镁、铁、锰、铜、锌含量进行研究，结果表明，影响钙与镁、铁与锰、铜与锌分布的主因子分别在相同的主成份组中，钙与镁、铁与锰、铜与锌之间的相关系数较大，铁、锰、铜、锌之间均为极显著正相关关系，钙与铁、锰、铜、锌均为负相关关系，说明元素的生物地球化学属性对其地理分布有较大的影响。     

农林复合经营研究──桉树人工林间种西瓜对林木和土壤的效应

本文调查研究了雷州林业局纪家、河头林场桉树人工林间种西瓜对林木和土壤的影响．结果表明，利用造林前空隙种一造西瓜或在桉树林地间种西瓜，均有利于桉树生长．单位面积林木蓄积量和年生长量均比对照林分显著增加，经济效益显著；土壤养分也有增加。作为农林复合经营的有益尝试，值得在有条件的地区推广。     

杉木观光木混交林和杉木纯林群落细根生产力、分布及养分归还

研究了福建三明27a生杉机光木混交林和杉木群落细根（d＜2mm）的生产力、分布、和养分归还。结果表明，混交林细根生物量、N、P养分现存量分别为5．381thm^2、48．085kghm^-2和4．174kghm^-2，分别比杉木纯林增加17．4％、27．2％和20．0％，混交林林细根的年净生产力达4．124thm^-2a^-1，比纯林高出16．9％，混交林杉木和观光木细根均在表层土壤富集，而在较深层土壤再会得分布具镶嵌性；与混交林杉林相比，纯林杉木土吉表层细根量较少，最大分布层次下移，混交林中观光木细根的周转速率咪1．16，杉木为0．96和0．95；而林下植被层细根周转速率（1．46－1．52）均同于相应的乔木层，混交林细根的年死亡量、N和P养分年归还量分别达2．119thm^-2、18．559kghm^-21．565kgkhm^-2，分别是纯林的1．21倍、1．23倍和1．14 倍，其中林下植被细根占有较为重要位置，对细根分布与土壤性质的相关分析表明，细根的垂直分布与土壤全N的相关性最强（0．87－0．89）。     

鼓翅皱膝蝗生态学特性研究

在甘肃省夏河县对鼓翅皱膝蝗的种群结构、数量变动、空间格局及动脉进行了系统研究。鼓翅皱膝蝗1a发生1代，以卵在土中越冬，翌年5月中旬开始孵化出土，6月上旬达到出土高峰，此期蝗虫种群仅由1龄和2龄蝗蝻组成，其中1龄蝗蝻占81.8％，2龄蝗蝻占18.2％，成虫于7月上旬开始羽化，8月上旬达到羽化高峰，此期的成虫数量达61.3％，而蝗蝻仅占38.7％，蝗蝻期约为72d，成虫寿命54d左右，每雌平均产卵32.6粒。鼓翅皱膝蝗在草地上属聚集分布，蝗蝻发生期种群的空间动态主要表现出扩散趋势，但初孵化出土时有短暂的聚集行为。取食量随龄期增大而增大，每头鼓翅皱膝蝗取食牧草量蝗蝻期平均为1.5g，成早期约为5.8g，成早期的食量是蝗蝻期的3.7倍。表3参12     

不同氮肥与磷肥的互作效应

利用盆栽试验研究了潮土中不同氮肥与磷肥的互作效应，结果表明：不同氮肥与磷肥的配合施用对潮土中油菜的生长和养分吸收有显著的交互作用。生长初期，施氮并不能促进、甚至会抑制油菜的生长，氯化铵较其它氮肥作用突出。随着生长期的延长，氮肥对油荣生长的促进作用逐渐显现，但氯化铵的促进作刚仍低于其它氮肥。植株养分累积受不同氮肥影响的规律与植株干物质累积表现的规律基本一致。土壤有效磷含最受不同氮肥影响较小，而水溶性磷含量因施用不同氮肥表现出显著的差异，特别是在生长初期的土壤中。相关分析结果表明，油菜生长初期的干物质质量与土壤水溶性磷含量达到极显著相关（r=0．727^＊＊）。因此推测，不同氮肥对油菜生长的影响可能因氮肥降低土壤中磷的有效性所致，这些结果对今后的合理施肥提供了重要的参考依据。     

Study of the dynamics of estuarine and coastal waters using remote sensing: the Tinto-Odiel estuary, SW Spain

This paper deals with the application of satellite images to characterize some aspects of the circulation dynamics of the Tinto-Odiel estuary using turbidity patterns as ‘natural tracers’. 15 images (Landsat TM and Spot HRV) were processed to provide synoptic, instantaneous views of the circulation patterns under different environmental conditions. In addition, a comparison was made between results of oceanographic field work, using biplanes and fluorescent tracers, and satellite image turbidity patterns used as ‘ground truth’ data for specific hydroclimatic situations. This approach allowed (1) the identification and mapping of dynamic processes of interest during a theoretical tidal cycle, (2) the elaboration of additional information on the ‘flow schemes’ at the mouth of the estuary with improved spatial and temporal resolution, and (3) the supply of basic data to improve the knowledge of exchange processes between estuarine and coastal waters. The results of this study are considered to be useful for the management of the estuarine system.     

Female benefit,male risk: Polyandry in the true armyworm Pseudaletia unipuncta

In Lepidoptera polyandry is common and females may increase their lifetime reproductive output through repeated matings if they acquire essential resources from male ejaculates. However, the paternity of males mating with previously-mated females is far from assured unless sperm precedence is absolute. In this study on the polyandrous armyworm, Pseudaletia unipuncta, we used two strains of male (the black-eyed wild type and a red-eyed homozygous, recessive mutant), mated with red-eyed females, to determine (i) whether male investment has any impact on female reproductive output, and (ii) if females do benefit from multiple matings, to what extent males fertilize the eggs to which they contributed. Multiple mating resulted in a significant increase in both the fecundity and longevity of females. However, the degree of sperm precedence (those eggs fertilized by the second male) varied from 0–100%, but was not affected by either male size or age, or by the duration of copulation. In cases where sperm precedence was <50% (x = 12%) females produced significantly more eggs (1384 versus 940) prior to the second mating than females where sperm precedence was >50% (x = 89%), indicating that the quality of the first mating influenced the fertilization success of the female's second mate.     

Terpenes and phenolics in response to nitrogen fertilization: A test of the carbon/nutrient balance hypothesis

Nitrogen fertilization resulted in a linear increase in the growth ofAbies grandis seedlings, but linear decrease in foliage concentrations of phenolic compounds. These data are consistent with the inverse relationship between growth and production of carbonbased secondary chemicals predicted by the carbon/nutrient balance (CNB) hypothesis. However, in contrast to predictions of the CNB hypothesis, nitrogen fertilization had no effect on foliage terpene concentrations. The results suggest that not all carbon-based chemicals respond in the same manner to environmental variation, and that the carbon/nutrient balance hypothesis does not adequately explain all patterns of environmentally-induced variation in secondary metabolism.     

川西亚高山白桦林小气候的时空动态特征

对川西亚高山白桦林(海拔2 540 m)内太阳辐射、空气温湿度以及土壤5 cm和15 cm层温度等进行了连续的定位观测.结果表明:1)林冠下的太阳辐射日进程与林冠上的不同,但辐射强度随着太阳高度角的变化而变化;林冠下太阳辐射日总量不仅受林冠上辐射日总量的影响,也受森林群落生长季节的影响;春、夏和秋季,林冠下平均辐射日总量分别占林冠上平均辐射日总量的53.1%、39.4%和55.8%.2)夏季,白天空气温度高于土壤温度,而夜间则相反;空气温度和土壤温度的日极端温度出现的时间不同步,空气温度对太阳辐射强度的敏感性比土壤温度的敏感性高.3)春季,土壤表层>4℃的积温高于空气和土壤底层>4℃的积温;夏季,>4℃的积温由高到低的次序为:林冠下空气>土壤5 cm层>土壤15 cm层,而秋季的比较结果与之相反;空气日平均温度与土壤日平均温度有显著的线性关系(P<0.001).4)林冠下的空气相对湿度(RH)比林冠上的高,林冠下的空气RH日变幅和季节性变幅比林冠上的小.图7表1参19