内蒙古典型草原4种植物凋落物分解速率与气候因子之间的定量关系

文章报道了内蒙古典型草原羊草（Ａｎｅｕｒｏｌｅｐｉｄｉｕｍ ｃｈｉｎｅｎｓｅ）,大针茅（Ｓｔｉｐａ ｇｒａｎｄｉｓ）,猪毛菜（Ｓａｌｓｏａａ ｃｏｌｌｉｎａ）和芨芨草（Ａｃｈｎａｔｈｅｒｕｍ ｓｐｌｅｎｄｅｎｓ）的凋落物的分解速率与气温和降水之间的关系,建立了动态模型Ｘ（ｔ）／Ｘ（Ｏ）＝ｅ＾－（ａｔ－ｂΣＴ－ｃΣｐ）．其中ｔ表示时间,Ｘ（ｔ）是ｔ时凋落物残留量,ΣＴ是累计气温,ΣＰ是累计降水量。气     

小兴安岭阔叶红松林凋落物产量及动态的研究

小兴安岭阔叶红松林凋落物产量及动态的研究刘传照,李景文,潘桂兰,李传荣（东北林业大学红松研究所,黑龙江带岭１５３１０６）ＬｉｔｔｅｒＰｒｏｄｕｃｔｉｏｎａｎｄＤｙｎａｍｉｃｓｉｎＢｒｏａｄｌｅａｖｃｄ－ＫｏｒｅａｎＰｉｎｅＦｏｒｅｓｔｓｉｎＸｉａｏｘｉｎｇａｎＭｏｕｎｔａｉｉｌｓ￥ＬｉｕＣｈｕａｎｚｈａｏ;ＬｉＪｉｎｇｗｅｎ;ＰａｎＧｕｉｌａｎ;ＬｉＣｈｕａｎｒｏｎｇ（ＩｎｓｔｉｔｕｔｅｏｆＫｏｒｅａｎＰｉｎｅＳｔｕｄｉｅｓ,ＮｏｒｔｂｅａｓｔＦｏｒｅｓｔｒｙＵｎｉｖｅｒｓｉｔｙ,Ｄａｉｌｉｎｇ,Ｈｅｉｌｏｎｇｊｉａｎｇ１５３１０６）．ＣｈｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（６）：２９－３３．Ｔｈｒｅｅ－ｙｅａｒｓｔｕｄｙｗａｓｄｏｎｅｏｎｌｉｔｔｅｒｐｒｏｄｕｃｔｉｏｎａｎｄｄｙｎａｍｉｃｓｕｎｄｅｒｂｒｏａｄｌｅａｖｅｄ－ＫｏｒｅａｎｐｉｎｅｆｏｒｅｓｔｓｉｎｔｈｅＸｉａｏｘｉｎｇａｎＭｏｕｎｔａｉｎｓ。Ｒｅｓｕｌｔｓｓｈｏｗｅｄｔｈａｔａｎｎｕａｌｌｉｔｔｅｒｆａｌｌｉｓ４．２５±０．１７ｔ．ｈａ￣（－１）．ｙｒ￣（－１）．Ａｍｏｎｇｔｏｔａｌｌｉｔｔｅｒｆａｌｌ,ｌｅａｆｌｉｔ     

9种新的人类染色体异常核型报告

发现９种新的人类染色体异常核型,分别为：４６,ＸＸ,ｔ（２;１０）（ｑ３３;ｑ１１）;４６,ＸＹ,ｔ（１０;１２）（ｑ２６;ｑ２２）;４６,ＸＹ,ｔ（６;１５）（ｐ２３;ｑ２３）;４６,ＸＹ,ｔ（１;６）（ｐ３６;ｑ２１）;４６,ＸＹ,ｔ（１;１９）（ｐ３２;ｐ１３）;４６,ＸＹ,ｔ（１６;１８）（ｑ２２;ｑ２１）;４６,ＸＹ,ｉｎｖ（１）（ｐ３６ｑ２５）;４６,ＸＹ,ｔ（１３;１７）（ｑ１２;ｑ２５）;４６,ＸＹ,ｔ（１５;２１）（ｑ２６;ｑ１１）。异常核型是导致自然流产和不育的原因。     

包容生态因子的广义Logistic模型

以Ｌｏｇｉｓｔｉｃ模型为代表的种群（ｘ）生长模型,仅依赖于时间（ｔ）,Ｘ＝ｆ（ｔ）,它是表达某一环境下生物过程的数学模型,其增长率参数（μ）为常数。本文发展了一种包含生态因子的广义Ｌｏｇｉｓｔｉｃ模型,Ｘ＝ｆ（Ｐ,ｔ）,ｐ表示生态因子,认为增长率是与生态因子有关的参数：μ＝μ０ｆ（ｐ）,该模型可以概括在不同环境下种群增长的重复试验,使用作物分期播种资料,建立了水稻干物质积累过程与生育阶段（时间）、播种期、太阳辐射、温度之间的关系,结果表明：该模型可以解释干物重变异的９６．９％。     

秦岭南坡旬河流域及邻近地区森林与其生境关系的初步研究

秦岭南坡旬河流域及邻近地区森林与其生境关系的初步研究康慕谊（西北大学地理系,西安７１００６９）ＲｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎＦｏｒｅｓｔＶｅｇｅｔａｔｉｏｎａｎｄＩｔｓＨａｂｉｔａｔｓｉｎＸｕｎｈｅＲｉｖｅｒＢａｓｉｎｏｆＱｉｎｌｉｎｇＭｏｕｎｔａｉｎａｎｄＩｔｓＡｄｊａｃｅｎｔＡｒｅａｓ￥ＫａｎｇＭｕｙｉ（ＤｅｐａｒｔｍｅｎｔｏｆＧｅｏｇｒａｐｈｙ,ＮｏｒｔｈｗｅｓｔＵｎｉｖｅｒｓｉｔｙ,Ｘｉａａｎ７１００６９）．ＣｈｉｎｅｓｅＪｏｕｒｎａｌｏｆＥｃｏｌｏｇｙ,１９９３,１２（６）：６２－６６．Ｐｒｉｎｃｉｐｌｅｓｏｆｖｅｇｅｔａｔｉｏｎｅｃｏｌｏｇｙａｎｄｍｅｔｈｏｄｏｆｍｕｌｔｉｖａｒｉａｔｅａｎａｌｙｓｉｓ（ＤｏｕｂｌｅＳｉｅｖｉｎｇＳｔｅｐＲｅｇｒｅｓｓｉｏｎ）ａｒｅａｐｐｌｉｅｄｔｏｒｅｖｅａｌｔｈｅｇｅｎｅｒａｌｒｅｌａｔｉｏｎｓｈｉｐｂｅｔｗｅｅｎｆｏｒｅｓｔｖｅｇｅｔａｔｉｏｎａｎｄｉｔｓｈａｂｉｔａｔｓｉｎｔｈｅｕｐｐｅｒａｎｄｍｉｄ－ｄｌｅｒｅａｃｈｅｓｏｆＸｕｎｈｅＲｉｖｅｒｂａｓｉｎａｎｄｔｈｅｉｒａｄｊａｃｅｎｔａｒｅａｓ。Ｔｈｅｒｅｓｕｌｔｓｓｈｏｗｔｈａｔｔｈｅｓｐｅ     

道路的生态学影响及其生态建设

道路的生态学影响及其生态建设章家恩,徐琅（中国科学院南京土壤研究所,２１０００８）ＥｃｏｌｏｇｉｃａｌＩｍｐａｃｔｓｏｆＲｏａｄｓａｎｄＩｔｓＥｃｏｌｏｇｉｃａｌＣｏｎｓｔｒｕｃｔｉｏｎ．￥ＺｈａｎｇＪｉａｅｎ;ＸｕＱｉ（ＩｎｓｔｉｔｕｔｅｏｆＳｏｉ...     

气候变化对农业害虫的潜在影响

气候变化对农业害虫的潜在影响张润杰何新凤（中山大学昆虫学研究所生物防治国家重点实验室,广州５１０２７５）ＰｏｔｅｎｔｉａｌＥｆｅｃｔｓｏｆＣｌｉｍａｔｅＣｈａｎｇｅｏｎＡｇｒｉｃｕｌｔｕｒａｌＩｎｓｅｃｔＰｅｓｔｓ．ＺｈａｎｇＲｕｎｊｉｅ,ＨｅＸｉ...     

灵长类家域的研究

灵长类家域的研究李保国刘安宏（西北大学生物学系,西安７１００６９）（西安市林业局,７１０００３）ＨｏｍｅＲａｎｇｅＳｔｕｄｙｏｆＰｒｉｍａｔｅｓ．￥ＬｉＢａｏｇｕｏ（ＤｅｐａｒｔｍｅｎｔｏｆＢｉｏｌｇｙ,ＮｏｒｔｈｗｅｓｔＵｎｉｖｅｒｓｉｔｙ,Ｘｉａ...     

国产蜘蛛抱蛋属的细胞分类学研究I.四个广西特有种的核型

研究了广西特有的４种蜘蛛抱蛋属植物的核型,结果如下：巨型蜘蛛抱蛋,２ｎ＝３８＝２４ｍ（２ｓａｔ）＋２ｓｍ＋１２ｓｔ;长药蜘蛛抱蛋,２ｎ＝３６＝１８ｍ＋２ｓｍ（２ｓａｔ）＋１６ｓｔ;广西蜘蛛抱蛋,２ｎ＝３６＝１８ｍ＋４ｓｍ（２ｓａｔ）＋１４ｓｔ,隆安蜘蛛抱蛋,２ｎ＝３８＝２０ｍ＋６ｓｍ（２ｓａｔ）＋１２ｓｔ。以上核型都属２Ｃ,具有明显的二型性．     

水分胁迫下湖北海棠根系脂氧合酶活性与ABA积累的关系

采用无细胞体系（ｃｅｌｌ－ｆｒｅｅ ｓｙｓｔｓｍ）及非离体根,研究了湖北海棠（Ｍａｌｕｓ ｈｕｐｅｈｅｎｓｉｓ（Ｐａｍｐａｎ．）Ｒｅｈｄ．）实生幼苗根中脂氧合酶（ＬＯＸ）活性和脱落酸（ＡＢＡ）生物合成及胁迫诱导ＡＢＡ积累的关系。结果表明,水分胁迫（３０％ＰＥＧ处理或０．６ｍｏｌ／Ｌ甘露醇处理）及盐胁迫（０．２ｍｏｌ／ＬＮａＣｌ）诱导ＡＢＡ积累的同时,ＬＯＸ活性也上升,两者呈一致关系。ＬＯＸ专一抑制     

Convergence results for contact branching processes

The link between the multi-type contact birth process and the spatial deterministic S-->I epidemic is exploited to give convergence results for a multi-type Markovian contact branching process. Let U(t) be the position of furthest spread by time t in a specific direction. The asymptotic speed of translation of the distribution function of U(t) is derived and U(t)/t is shown to converge in probability to this speed.     

On the Gompertzian growth in the fractal space-time

An analytical approach to determination of time-dependent temporal fractal dimension b(t)(t) and scaling factor a(t)(t) for the Gompertzian growth in the fractal space-time is presented. The derived formulae take into account the proper boundary conditions and permit a calculation of the mean values b(t)(t) and a(t)(t) at any period of time. The formulae derived have been tested on experimental data obtained by Schrek for the Brown-Pearce rabbit's tumor growth. The results obtained confirm a possibility of successful mapping of the experimental Gompertz curve onto the fractal power-law scaling function y(t)=a(t)tb(t) and support a thesis that Gompertzian growth is a self-similar and allometric process of a holistic nature.     

The saturated repair kinetics of Chinese hamster V79 cells suggests a damage accumulation--interaction model of cell killing

The aim of this study is to determine whether the repair process in log-phase Chinese hamster V79 cells exposed to X rays is unsaturated, saturable, or saturated. The kinetics of recovery from damage induced by 2 to 14 Gy of 250 kVp X rays was studied by treating cells with 0.5 M hypertonic saline for 20 min at different postirradiation repair intervals. From the kinetic data, the repair half-time (t1/2), the repair time (time needed to attain maximal survival), and the recovery ratio were calculated. The results show that the t1/2 (1.42 min/Gy) and the repair time (6.04 min/Gy) increase linearly with dose, the logarithm of the recovery ratio increases linear-quadratically with dose, and the D0 increases linearly with repair interval at a rate of 2.4 cGy/min. From these results we suggest a model: the repair of damage (undefined lesions) necessary for cell survival is effected by a repair process (t 1/2 of 1.42 min/Gy) which is saturated at doses as low as 2.4 cGy; repair saturation leads to a dose-dependent accumulation of repairable lesions; and interaction among accumulated repairable lesions results in the induction of irreparable (lethal) lesions. We call this the accumulation-interaction model of cell killing by low-LET radiation.     

长白山暗针叶林苔藓枯落物层的降雨截留过程

对长白山北坡暗针叶林地面苔藓枯落物层 (苔藓植物和枯落叶交织而成的层状结构 )持水能力、截留降雨过程及动态变化进行了研究。结果表明苔藓枯落物层持水能力很强 ,最大持水量相当于 4 .8mm的降雨量 ,这个结果大于将苔藓与枯落物分开来测定的结果之和 ,说明成层结构能够提高持水能力。在一次降雨过程中对降雨截留过程的观测发现 :持水量刚开始随降雨增加而增加 ,到一定量时 ,降雨再增加 ,持水量反而缓慢下降。对持水动态变化一个月的观测 ,表明苔藓枯落物层水分蒸发较快 ,当长时间无雨时 ,持水量显著下降 ,当降雨再次发生时 ,持水量迅速回升 ,这种动态过程伴随着降雨的发生而不断往复。此外 ,在夜间苔藓枯落物层有吸收空气中水气的特点 ,吸收量受空气湿度的影响     

A parity-dependent immigration-birth-death-emigration process.

An immigration-birth-death-emigration process is studied when the immigration, birth, death, and emigration parameters depend on two parity classes of individuals, namely, zero and nonzero parity. The expected number of individuals in the population at time t and that of emigrants in (0,t) of both parity classes are obtained using the probability generating function (pgf) technique. The explicit expression for the pgf of the process is derived when the parameters are parity-independent. Population extinction and some limiting results are also discussed.     

Hydrodynamic Analysis of C-start in Crucian Carp

The kinematics of turning maneuvers of startled Crucian Carp (Carassius auratus) are presented. All escape response observed are C-type fast-starts. The position of the center of mass and the me,merit of inertia of the fish are calculated. The results show that the position of the center of mass is always at 35% of the length of the fish from the head and the position of the center of mass and rroment of inertia can be considered unchanged during C-start of Crucian Carp. Hydro-dynamic analysis of the C-start is given based on the kinematics data from our experiments. The C-start consists of three stages. In stage 1, the tail fin of fish rapidly flaps in one direction, and a large moment acts on the fish‘s body, which rotates around the center of mass with an angular acceleration. In stage 2, the tail fin flaps more slowly in the opposite direction at slower speed, the fish‘s body rotates around the center of mass with angular deceleration and the center of mass of the fish moves along an are. In stage 3, the moment approximately equals zero, the fish‘s body stops rotating and the center of mass the moves along a straight line.     

Stochastic models for the Trojan Y-Chromosome eradication strategy of an invasive species

The Trojan Y-Chromosome (TYC) strategy, an autocidal genetic biocontrol method, has been proposed to eliminate invasive alien species. In this work, we develop a Markov jump process model for this strategy, and we verify that there is a positive probability for wild-type females going extinct within a finite time. Moreover, when sex-reversed Trojan females are introduced at a constant population size, we formulate a stochastic differential equation (SDE) model as an approximation to the proposed Markov jump process model. Using the SDE model, we investigate the probability distribution and expectation of the extinction time of wild-type females by solving Kolmogorov equations associated with these statistics. The results indicate how the probability distribution and expectation of the extinction time are shaped by the initial conditions and the model parameters.