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1.
国家大型煤电基地生态环境监测技术体系研究——以内蒙古锡林郭勒盟煤电基地为例 总被引:2,自引:0,他引:2
随着我国煤电基地建设进程的不断加快,煤电基地建设与开发活动引起的环境问题也日趋严重。了解生态环境质量现状,评估其对生态系统与人民健康水平的影响,制定合理的保护、治理、恢复策略是煤电基地环境保护工作的重中之重,而生态环境监测是解决上述问题的基础。然而,现有的监测技术体系普遍存在自动化水平较低、成本较高、时空覆盖面较低等问题。鉴于物联网技术在提高信息采集效率和改善信息获取方式方面的作用日益显著,所以将物联网技术应用于煤电基地生态环境监测,从感知层、传输层、支撑层、应用层、用户层的角度明确生态环境监测技术体系,为解决上述问题提供有效途径。 相似文献
2.
略论棕榈科与新分出的省藤科的系统分类、演化、区系地理及主要的经济用途 总被引:6,自引:0,他引:6
棕榈科原省藤亚科因其子房壁及外果皮被倒生、螺旋状排列的鳞片所覆盖,而区别于其他亚科,因而独立分出成一新科--省藤科。作者讨论了棕榈科的祖先种可能在石炭纪时,自原始裸子植物开以顿目在分化、衍生出苏铁目祖先种的进化干上,于白垩纪时分化出的一个分支。在棕榈科的祖先种出现不久后,在其进化的分支上,于白垩纪后期又分化出一旁支,成为棕榈科的姊妹科--省藤科的祖先种。从两祖先种分别再分化、衍生出现今分布地球上该二科的属与种。两科、尤其前者是被子植物、尤其是单子叶植物中最原始的类群之一。作者还提出棕榈科象牙椰亚科与贝叶棕亚科是该科最原始或较原始的两类群;槟榔亚科和腊材榈亚科是较进化的两类群;而水椰亚科祖先种可能源于象牙椰亚科的祖先种,但又演化为该科最进化与特化的类群。省藤科省藤亚科略比鳞果榈亚科原始。作者讨论了两科为泛热带分布的科,指出两科的"现代分布区"在南北两半球热带地区,少数种还延伸分布到两半球暖亚热带、甚至达中亚热带地区,分布区边缘最北达日本中部、中国长江流域及黄河下游的南部,美国加利佛尼亚州与佛罗里达州和地中海北部;最南达智利中部和新西兰南部;而"现代分布中心"在热带与暖亚热带的亚洲,中、南美洲,大洋洲及非洲的东、南、西部;但分布区的"密集中心"则在热带亚洲、热带中及南美洲、南太平洋群岛及非洲东南部。作者还介绍了近50年我国南方引种驯化成功的两科植物近400种(见*图谱),其中少数为耐寒的种类,有的种已引种到长江流域或更北的地区。引种的大部分种都有其重要的经济用途,包括:1. 食用,如淀粉和树液可制"西米"或制糖,酿酒、醋或作饮料;果或种子榨油,供食用或工业用;某些种的嫩芽作蔬菜,甚至种子代咖啡饮用;2. 药用,有消炎、止血、活血、驱虫、抗癌等用;3. 建筑、工艺与日用品,包括不少种的树干供建普通房子、桥梁、小船;少数种可提制工业用蜡;许多种的纤维制高级缆绳和编织品;还制工艺品与日用品等;4. 代表热带景观的园林工程、绿化及美化环境的观赏树和人行道树及建造园林景观生态类型的树种等。 相似文献
3.
我国实施了诸多生态保护修复工程,取得了显著成效。然而,以往工程多以湿地、森林、草原等单一类型的生态系统为保护修复目标,缺乏区域整体性、系统性考虑。2016年以来,我国开始从完整流域的视角出发,系统考虑生态系统完整性、自然地理单元连续性和社会经济可持续性,实施山水林田湖草沙一体化保护和修复工程。该类工程保护修复目标多样、内容庞杂,因而成效评估面临子项目类型多、空间尺度多、目标维度多、项目实施周期短等诸多挑战。就空间尺度而言,评估对象既要涵盖常规评估中相对较大的、确定的空间范围,也要涵盖具有相对类似生态问题或目标的保护修复单元,以及实际采取措施的子项目;就时间尺度而言,既要考虑工程实施结束时的成效,也要考虑实施结束后的成效动态;就评估内容而言,既要关注社会、生态、经济效益,也要考察工程措施与生态效应之间的关系、不同类型子项目的关联性与协同性、工程的整体性与系统性。研究基于上述背景制定了一个新型评估框架,重点强调基于子项目、保护修复单元以及工程范围三个尺度的指标体系,以及生态、社会、经济、管理四个方面的评估内容。新的评估框架将有助于完善山水林田湖草沙一体化保护和修复工程标准体系,为推进国土空... 相似文献
4.
将小叶杨分别与其他11个树种枯落叶粉碎混合后进行室内分解培养,分析不同树种枯落叶混合分解对土壤性质的影响及其相互作用.结果表明:12个树种枯落叶单独混土分解均明显提高了土壤脲酶、脱氢酶、磷酸酶活性和有机质、碱解N含量,但对土壤速效P含量和土壤阳离子交换量(CEC)的影响差异较大,其中柠条和紫穗槐枯落叶改善土壤性质的效果明显.小叶杨分别与油松、侧柏、刺槐、白榆枯落叶混合分解,对土壤微生物数量的影响存在相互促进作用;小叶杨分别与侧柏、柠条枯落叶混合分解对土壤有机质、速效P、速效K含量和CEC的影响存在相互促进作用,但对土壤大部分酶活性的影响却存在相互抑制作用;小叶杨与落叶松枯落叶混合分解对土壤多数酶活性和养分含量的影响存在相互促进作用,而与樟子松枯落叶混合分解时则有抑制作用.总体上,小叶杨分别与白榆、油松、落叶松和刺槐枯落叶混合分解可促进土壤性质的改善,而与侧柏、柠条、樟子松、沙棘和紫穗槐枯落叶混合分解时则相互抑制. 相似文献
5.
Mt. Wuyi, located at 27°37‛-27°54‛ N, 117°27‛-117°51‛ E, is the highest mountain
in South-East China. Its main peak, Huanggangshan, is 2158 m above the sea level. In 1955, P.
C. Chen organized the first expedition to Mt. Wuyi, and the authors investigated the different
ravines and the forests of that area in 1976 and from 1979 to 1984 respectively. Up to now
355 species of the bryophytes have been found in Mt. Wuyi.
I. The influence of the factors of geological history on the bryoflora of Mt. Wuyi
Fujian Province, belonging to Cathaysian, one of three Chinese ancient lands, was a part
of ocean until the end of the lower Tertiary. In the early Devonian, Fujian uplifted above the
sea level, but it submerged in the sea later, and then uplifted above the sea level again in the
upper Triassic.
By the end of the lower Triassic the Himalayan movement influenced the paleogeography
of China deeply, and the eastern and central mountains of Fujian uplifted again. In the Tertiary, Fujian was influenced by the hot maritime weather, so the tropical evergreen forests existed
in southern Fujian at that time. The conclusion was made by Z. B. Zhao in 1983 after his long
period of study on geological history of Fujian Province since the Yanshan movement.
According to the morden geographical distribution of Chinese bryophytes, it seems that the
above influence might be related to the bryophytes of Mt. Wuyi and also the southern part of
Zhejian Province. By the end of the Tertiary the weather became cold in most parts of China.
Since then the cold weather and hot weather alternated several times. One kind of the endemic elements of the bryoflora formed in the area from the south-eastern coast of China to the
southeastern Xizang (Tibet), including Japan. They are not specialized at the family level or
closely related to each other, but they have similar distribution and belong to different families.
In the Quaternary, Mt. Wuyi gradually uplifted following the Himalayan movement. As the
weather cooled down in the upper part of the mountain, deciduous broad-leaved and needleleaved trees increased there. Meanwhile, temperate genera and species of the bryophytes spread and
invaded South China and entered Mr. Wuyi. Rhytidiadelphus and Hvlocomium probably began to grow in Mt. Wuyi at that time, and their distribution is quite different from their primary one. On the other hand, a part of tropical and subtropical bryophytes might enjoy the
changed weather and environment in the Quaternary and existed in a few small localities of Mt.
Wuyi, and the genera Haplomitrium, Endotrichella and Floribundaria are probably their representatives. From the point of view of geological history we are now living in the interglacial
period and the present natural conditions will last continuously, so they will steadily influence
the bryoflora of Mt. Wuyi in a long period of time.
2. Essential characteristics of the bryoflora in Mt. Wuyi
Due to the geographical position and the other factors of Mt. Wuyi the bryoflora is represented by numerous tropical and subtropical elements (34.1%), but the East-Asiatic endemic ones
(79.2%) are characteristic of the bryoflora in Mt. Wuyi (Tab. 1). The tropical and subtropical
families of the bryophytes, found south of Changjiang (Yangtzi) River, are Haplomitriaceae (1
genus, 3 species), Porellaceae (2 genera, 8 species), Frullaniaceae (2 genera, 10 species), Lejeun eaceae (21 genera, 35 species), Trachypodaceae (3 genera, 4 species), Meteoriaceae (10 genera, 17
species), Neckeraceae (5 genera, 8 species) and Hookeriaceae (3 genera, 3 species). The above
8 families, including 46 genera and 85 species, represent about 1/4 genera (24.3%) and less than
1/4 species (23.9%) of the bryoflora of Mt. Wuyi.
Most species of East-Asiatic elements show very close relationships with Japan, and are
widely distributed from the low altitude of Mt. Wuyi to the summit of Mt. Huanggangshan.
However, the Holarctic species (26.8%) are also important elements of the bryoflora in Mt.
Wuyi, showing its transition nature, although it is located in the subtropics. Moreover, the in fluence of the Himalayas also exists in Mt. Wuyi, and the Himalayan elements cover 14.4% in
the bryoflora of Mt. Wuyi. The similarity coefficients between the bryofloras of Central and
South America, Africa and Oceania and that of Mt. Wuyi are from 5.0-9.2% respectively. The
endemic species are not very many and cosmopolitan species are only 7 there.
In 1958, P. C. Chen designated Mt. Wuyi as “the transition region of South and North
China rich in East-Asiatic genera and species”. His very important conclusion is essentially in
accordance with the fact of the bryoflora on Mt. Wuyi. Recently, some of the new records fur ther show the characteristics of the bryoflora in Wuyi. Two facts are worth being mentioned.
One is that East-Asiatic genera are only five in Mt. Wuyi. However, there are 9 East-Asiatic
genera in Mt. Huangshan more than in Mt. Wuyi; 4 East-Asiatic genera are recorded in Mt.
Shennongjia. The other is that epiphyllous liverworts in Mt. Wuyi, consisting of 7 families, 21
genera and 36 species, are less than on Hainan Island and Xishuangbannan, located in the tro pics in China.
3. Comparison between the bryoflora of Mt. Wuyi and those of the neighbouring regions
As China covers a very large area, bryofloristic elements are quite different in the diffe rent regions. In this section, we are concentrated on making a comparison between the bryof loras of Mt. Wuyi and the regions belonging to the Central China of the bryoflora named by
P. C. Chen.
Huaping Forest Region, Guangxi Zhuang Autonomous Region in South China, with both
latitute and altitude very similar to Mt. Wuyi, is included in this comparison (Fig. 1). According to the rough estimation, the similarity coefficient of moss genera between Mt. Wuyi and
Huaping is 56.3%, and those between the mountain and southern Zhejian and Mt. Huangshan,
Anhui, are 62.7% and 51.6% respectively, while the similarity coefficient of the genera of the
mossfloras between Mt. Shennongjia and Mt. Wuyi is 46.8%. Table 2 shows the statistics of
mosses in Mt. Wuyi and the others, but the bryoflora of Huaping needs further study However,
it is very interesting to note that Haplomitrium and Pleurozia of liverworts are both found in
Mt. Wuyi and Huaping Forest Region, and the similarity coefficient between the mossfloras of
Mt. Wuyi and Zhejian Province is also higher than those mentioned above.
Tropical and subtropical elements reduce towards the north in China, and temperate ones
increase. Huaping is located in the south, and, as expected, some tropical and subtropical
genera such as Hookeriopsis and Symphyodon have been found there, but not in Mt. Wuyi; several
temperate genera, such as Schwetschkeopsis and Fauriella, have been recorded in Mt. Huangshan,
but not in Mt. Wuyi. For some unknown reasons, Octoblepharum and Neckeropsis are only
found in southern Zhejiang, but not in Mt. Wuyi. Mt. Shennongjia, with its main peak over
1000 m higher than that of Mt. Wuyi, is located in its northwest, and more than ten temperate
genera, such as, Ceratodon, Aulacomnium Myurella, Bryonoguchia and Abietinella have been
found there.
Generally, Mt. Wuyi belongs to the central subtropical region of China, and East-Asiatic
endemic genera are the main elements of its bryoflora, but the bryoflora also consists of tropical and subtropical elements with some temperate ones.
4. East-Asiatic endemic genera in the bryoflora of Mt. Wuyi
In the bryoflora of Mt. Wuyi, one of the main elements, East-Asiatic endemic genera, should
not be neglected (Tab. 4). East-Asiatic endemic genera in Mt. Wuyi (five) are less than in Mt.
Huangshan and Mt. West Tianmu, although the positions of the latter two are very close to Mt.
Wuyi. East-Asiatic endemic genera of liverworts are Trichocolea and Macvicaria so far found
in Mt. Wuyi, and the mosses are Myuriopsis, Meteoriella, Pseudospiridentopsis (Fig. 1). Myuriopsis is only distributed in Taiwan Province and Mt. Wuyi, and the other four are distributed in Mt.
Huangshan or Mt. West Tianmu, and also in Taiwan, besides in Mt. Wuyi. About thirty EastAsiatic endemic genera have so far been known in China, which means that about one sixth of
East- Asiatic endemic genera of the bryophytes occur in Mt. Wuyi. We may notice that nine
and seven East-Asiatic endemic genera of the bryophytes have been recorded in Mt. Huangshan
and Mt. West Tianmu respectively. In Mt. Shennongjia, Central China, there are four East
Asiatic endemic genera, but only two have been found in the Huaping Forest Region, South
China. In Mt. Dinghua, located south of Mt. Wuyi, on East-Asiatic endemic genus of the bryophytes has so far been found.
East-Asiatic endemic genera of the bryophytes are mainly limited to China, Korea and Japan,
including the East Himalayas, rarely occur in South Asia, Siberia of the Soviet Union. Therefore,
these genera enjoy a warm and moist environment. In Mt. Wuyi, all the East-Asiatic endemic
genera are monotypic ones with a disjunct distribution. Now in Taiwan Province five of six
recorded East-Asiatic endemic genera are common to Mt. Wuyi. In Japan, about eleven, i.e.
one third of, East Asiatic endemic genera so far found are common to China, which shows a
long history of the phytogeographical relationships between Japan and China. East Asiatic endemic genera of the bryophytes might therefore exist on islands of Taiwan Province and Japan
before they were separated from the mainland of Asia. However the fossil evidence is still
lacking in the bryophytes, so we are not able to discuss about the distribution area and the distribution center of the East-Asiatic bryoflora in detail. The above estimation is more or less
related to geological history, and we assume that the East-Asiatic endemic genera have existed at
least since the end of the Tertiary. Starting from the Quaternary, the climatic change during
glacial epoch has been possibly the most important factor affecting the bryoflora in Asia, and
the upheaval of the Himalayas has stimulated the diversity and the specialization of the bryophy tes. Considering these factors, East-Asiatic endemic genera might be the “Tertiary fossil
plants”.
Another problem is difficult to explain, because Mts. Huangshan, West Tianmu and Shen nongjia were once influenced by glaciation directly, although Chinese geologists hold different
views. However, no evidence of glaciation has been found in Mt. Wuyi. It is worth to study the
close relationships between Mt. Wuyi, Mt. Huangshan and Mt. West Tianmu, where is the distri bution center of the East-Asiatic endemic genera. The above three mountain regions share half
of the East-Asiatic endemic genera, and about 32% genera of the others are found in two of
them (Fig. 2). Myuriopsis, one of the East Asiatic types, was only recorded in Taiwan Pro vince, Japan and Korea. Neodolichomitra, occuring in Taiwan Province, is endemic to China.
More or less the differentiation has taken place in Mt. Huangshan, Mt. West Tianmu and Mt.
Wuyi. The number of the East-Asiatic endemic genera is smaller in Mt. Wuyi, so it is possibly
located on the border of the distributional center of the East-Asiatic endemic genera. Moreo ver, three of four East-Asiatic endemic genera in Mt. Shennongjia are also found in Mt. Huang shan and Mt. West Tianmu, but the other East-Asiatic genus in Mt. Wuyi is common to the
mountain areas in SW China, the Qinglin Range of NW China, and the isolated mountain areas
of NE China. Considering all the characteristics of the bryoflora of Mt. Shennongjia, we assume
that Mt. Shennongjia may belong to another distribution center, including SW part of Sichuan
Province, and the other neighbouring mountains. 相似文献
6.
Stress activates the central and peripheral components of the stress system, i.e., the hypothalamic-pituitary-adrenal (HPA) axis and the arousal/sympathetic system. The principal effectors of the stress system are corticotropin-releasing hormone (CRH), arginine vasopressin, the proopiomelanocortin-derived peptides alpha-melanocyte-stimulating hormone and beta-endorphin, the glucocorticoids, and the catecholamines norepinephrine and epinephrine. Appropriate responsiveness of the stress system to stressors is a crucial prerequisite for a sense of well-being, adequate performance of tasks and positive social interactions. By contrast, inappropriate responsiveness of the stress system may impair growth and development, and may account for a number of endocrine, metabolic, autoimmune and psychiatric disorders. The development and severity of these conditions primarily depend on the genetic vulnerability of the individual, the exposure to adverse environmental factors and the timing of the stressful event(s), given that prenatal life, infancy, childhood and adolescence are critical periods characterized by increased vulnerability to stressors. The developing brain undergoes rapid growth and is characterized by high turnover of neuronal connections during the prenatal and early postnatal life. These processes and, hence, brain plasticity, slow down during childhood and puberty, and plateau in young adulthood. Hormonal actions in early life, and to a much lesser extent later, can be organizational, i.e., can have effects that last for long periods of time, often for the entire life of the individual. Hormones of the stress system and sex steroids have such effects, which influence the behavior and certain physiologic functions of individuals for life. Exposure of the developing brain to severe and/or prolonged stress may result in hyperactivity/hyperreactivity of the stress system, with resultant amygdala hyperfunction (fear reaction), decreased activity of the hippocampus (defective glucocorticoid-negative feedback, cognition), and the mesocorticolimbic dopaminergic system (dysthymia, novelty-seeking, addictive behaviors), hyperactivation of the HPA axis (hypercortisolism), suppression of reproductive, growth, thyroid and immune functions, and changes in pain perception. These changes may be accompanied by abnormal childhood, adolescent and adult behaviors, including excessive fear ('inhibited child syndrome') and addictive behaviors, dysthymia and/or depression, and gradual development of components of the metabolic syndrome X, including visceral obesity and essential hypertension. Prenatal stress exerted during the period of sexual differentiation may be accompanied by impairment of this process with behavioral and/or somatic sequelae. The vulnerability of individuals to develop varying degrees and/or components of the above life-long syndrome is defined by as yet unidentified genetic factors, which account for up to 60% of the variance. CRH has marked kindling and glucocorticoids have strong consolidating properties, hence both of these hormones are crucial in development and can alone produce the above syndrome. CRH and glucocorticoids may act in synergy, as in acoustic startle, while glucocorticoids may suppress or stimulate CRH, as in the hypothalamus and amygdala, respectively. A CRH type 1 receptor antagonist, antalarmin, inhibits both the development and expression of conditioned fear in rats, and has anxiolytic properties in monkeys. Profound stressors, such as those from sexual abuse, may elicit the syndrome in older children, adolescents and adults. Most frequently, chronic dysthymia and/or depression may develop in association with gastrointestinal complaints and/or the premenstrual tension syndrome. A lesser proportion of individuals may develop the classic posttraumatic stress disorder, which is characterized by hypocortisolism and intrusive and avoidance symptoms; in younger individuals it may present as dissociative personality disorder. 相似文献
7.
8.
Phylogenetic analysis of Adephaga (Coleoptera) based on characters of the larval head 总被引:5,自引:0,他引:5
R. G. BEUTEL 《Systematic Entomology》1993,18(2):127-147
Abstract. Characters of the head of adephagan larvae were examined and analysed phylogenetically. A labrum which is completely fused to the clypeofrons and the presence of a closed prepharyngeal tube are autapomorphies of Adephaga. Partial reduction of the fossa maxillaris, cardo and stipes forming a functional unit, the immobilization of the lacinia, attachment of M. craniolacinialis to the lateral stipital wall, and loss of one stipitopalpal muscle, are considered autapomorphies of Adephaga excluding Gyrinidae. Complete reduction of the fossa maxillaris and the presence of M. craniostipitalis medialis are possible autapomorphies of Adephaga excluding Gyrinidae and Haliplidae. The presence of caudal tentorial arms, insertion of the galea on the mesal side of palpomere I, and absence of the lacinia are considered synapomorphies of Trachypachidae and Dytiscoidea (Noteridae, Amphizoidae, Hygrobiidae, Dytiscidae). The presence of a slender, elongated process of the head capsule, which articulates with a corresponding socket of the cardo, is a possible autapomorphy of Dytiscoidea. The sinuate frontal sutures, distinctly protruding prementum, shortened M. craniostipitalis medialis, and absence of M. submentopraementalis are considered autapomorphies of Geadephaga excluding Trachypachidae. The presence of a regular row of hairs along the anterior hypopharyngeal margin is a possible autapomorphy of Geadephaga excluding Trachypachidae and Rhysodidae. Improvement of the hypopharyngeal filter apparatus suggests the monophyly of Anisochaeta. Presence of a penicillum and partial reduction of the lacinia are possible autapomorphies of Anisochaeta excluding Omophronini. Larvae of Cychrini, Carabini, Nebriini and Notiophilini are characterized by a strongly developed, cone-shaped hypodon. Postocular and cervical ridges, crosswise arrangement of antennal muscles, and a completely flattened hypopharynx are considered autapomorphies of Caraboidea Limbata. 相似文献
9.
G. B. Khomutov 《Biophysics》2011,56(5):843-857
Biophysicochemical approaches to the solution of nanotechnology problems associated with the design of functional biomimetic
nanosystems, hybrid and composite nanobiomaterials and study of their structure-function relationships. The results of studies
concerned with physicochemical mechanisms of the formation of organized biomimetic nanostructures and bioinorganic nanomaterials
in systems involving a bulky liquid phase and the interface (gas-liquid, solid-liquid, liquid-liquid)during the synthesis
and structure formation with the participation of the components of colloid systems, inorganic nanoparticles of various composition
and clusters of metals, surfactants, polyelectrolytes and their complexes are discussed. In the development of the methods
for the formation of composite bioinorganic nanosystems containing inorganic nanocomponents, two major approaches were used:
adsorption and incorporation into the biomolecular matrix or colloid system of presynthesized inorganic nanoparticles, as
well as the synthesis of the inorganic nanophase immediately in the biomolecular system. The methods of obtaining biomaterials
and nanosystems are based on the principles of biomimetics, biomineralization, self-assembly and self-organization, combination
and integration of a number of synthetic and physicochemical methods (physical and chemical adsorption, Langmuir technique,
the formation of polycomplexes, chemical linking, competitive interactions, and substitution of ligands in supramolecular
and coordination complexes) and nanocomponents of different nature. In particular, a novel approach to the preparation of
highly organized nanofilm materials was developed, which is based on the effect of self-assembly and self-organization of
colloid nanoparticles during the formation of their complexes with polyfunctional biogenic ligands in the volume of the liquid
phase in the absence of any surfaces and interfaces. The physical and chemical factors responsible for the formation of structurally
ordered biomolecular and composite nanosystems including nano-sized components of different nature and the possibilities to
control the composition, structure, and properties of resulting nanomaterials and nanosystems are discussed. The experimental
methods and approaches developed may be useful in studies of structure-property relationships and basic mechanisms of structural
organization and transformation at the nanoscales level in biological, artificial, and hybrid nanosystems. The problems of
practical application of the synthetic methods and the corresponding nanomaterials are discussed. 相似文献
10.
本文研究了广西龙胜县里骆林区、宜山县庆远林区、岑溪县七坪林区和田林县老山林区四种不同生态地理区域杉木人工林土壤微生物及其生化活性。研究结果表明:1.土壤微生物的总数及各类群数量均以龙胜县里骆林区和田林县老山林区杉木人工林土壤最高,岑溪县七坪林区次之,宜山县庆远林区最低。2.土壤生化活性包括土壤氮的转化强度,土壤碳的氧化代谢能力和土壤酶活性,也均以龙胜县里骆林区和田林县老山林区杉木人工林土壤最强,岑溪县七坪林区次之,宜山县庆远林区最弱。3.四种不同生态地理区域杉木人工林生长状况与土壤微生物的数量分布和生化活性表现相似规律,龙胜县里骆林区和田林县老山林区杉木人工林林木生长最好,岑溪县七坪林区次之,宜山县庆远林区最差。 相似文献
11.
鄂尔多斯市生态系统格局和质量变化及驱动力 总被引:2,自引:0,他引:2
生态系统变化是生态问题产生的主要驱动力之一,研究生态系统格局与质量变化对于认识人类活动与生态系统关系具有重要意义。鄂尔多斯市能源资源丰富,但生态环境脆弱,2000年以来,鄂尔多斯市在大规模开发能源的同时,也在不断加强生态环境的保护,而研究鄂尔多斯市生态系统格局与质量演变过程,对认识生态脆弱区发展与保护的关系有重要价值。应用遥感数据和GIS技术,评估了鄂尔多斯市生态系统类型与格局、生态系统质量的特征,以及2000年以来的时空变化趋势,分析了导致鄂尔多斯市生态系统格局与质量变化的驱动力因素。结果表明:(1)鄂尔多斯市的草地、荒漠裸地和农田为主要生态系统类型,分别占2010年市域面积的64.46%、21.34%与5.93%。(2)鄂尔多斯市城镇、灌丛、森林面积有所增加,草地、湿地、农田、荒漠裸地面积有所下降。城镇面积增幅最大,相对变化率增加33.37%,草地面积降幅最大,相对变化率减少0.78%,变化主要集中在中部、东北部。(3)鄂尔多斯市生态系统质量整体偏低,低等级与差等级的生态系统面积比例高达98.91%。全市的生态系统质量没有明显改善,其中生态系统质量有不同程度改善的面积为15.84%,质量降低的面积比例为15.29%。(4)生态系统格局与质量变化的主要驱动力有城市扩张、农田开垦、退耕还林(草湿)、生态保护、矿山开采等,鄂尔多斯市生态系统质量与降水、退耕还草工程、道路密度、温度、GDP1、放牧因子相关性显著。 相似文献
12.
生态地质环境系统研究应以地质学为基础,以生态学为指导,研究岩石、土壤、水、生物等在地质作用下产生的生态问题。秦岭生态地质特色鲜明,是催生生态地质基础理论、形成生态地质保护对策的理想实践地,迫切需要对秦岭生态地质环境角色地位予以系统剖析,梳理秦岭生态地质环境系统面临的主要挑战,构建秦岭生态地质环境系统框架体系。研究提出秦岭生态地质环境系统研究要把握以下关键思考:一是秦岭生态地质环境要素多元、圈层互馈过程复杂、灾害叠加影响效应突出、人-地-生相互作用强烈,立足生态秦岭面临的现实挑战,需认知秦岭生态地质环境系统的要素构成及家底,构建秦岭生态地质环境系统要素互馈演化模型,探索生态退化、水土流失和地质灾害共存递进关系,进而提出地质环境-生态环境-人类环境动态平衡调控对策;二是秦岭生态地质环境系统框架体系应以地质环境认知为基础,将生态环境充分融入地质环境之中整体考虑,并对各要素对生态环境影响进行梳理;其中,构造、地貌地质环境是“生态容器”,岩石、土壤及水文地质环境是“生态载体”,灾害地质环境是引起“生态损害”的重要因素,人类活动环境则为造成“生态扰动”的外在驱动;三是秦岭林体-土体-岩体-山体-水... 相似文献
13.
Shpakov AO Derkach KV Uspenskaia ZI 《Zhurnal evoliutsionno? biokhimii i fiziologii》2011,47(2):128-135
Natural amino acids and sugars in intracellular eukaryotes are known to regulate adenylyl cyclase (AC) and guanylyl cyclase (GC) systems that control the most important cell processes. The goal of the present work consisted in study of effects of natural amino acids and sugars and some of their derivatives on AC and GC activities of infusoria Tetrahymena pyriformis and Dileptus anser. Methionine, arginine, lysine, and tryptamine stimulated basic AC activity of T. pyriformis, whereas alanine, thyrosine, and cysteine decreased it. Methionine, glycine, alanine, thyrosine, arginine, and to the lesser degree tryptamine and histidine stimulated AC of D. anser. The GC activity of T. pyriformis are increased in the presence of tryptamine, tryptophane, histidine, arginine, and lysine, whereas glycine and aspartic acid, on the contrary, decreased it. Tryptamine, tryptophan, leucine, glutamic acid, serine, histidine, and alanine stimulated the GC activity of D. anser. Glucose, fructose, and sucrose stimulated the basal AC activity of both infusorians and GC of T. pyriformis, with glucose and sucrose increasing AC of T. pyriformis twice, while that of D. anser 4.5 times. Lactose stimulated AC and GC of T. pyriformis and was inefficient with respect to the D. anser cyclases, whereas mannose and galactose did not affect the enzyme activities in both infusorians. The study of the chemotactic response of infusorians to amino acids and sugars indicates that involved in realization of this response can be signaling pathways both dependent on and independent of cyclic nucleotides. Thus, it has been established for the first time that several amino acids and sugars affect functional activity of enzymes with cyclase activity of the infusorians T. pyriformis and D. anser. This confirms the hypothesis that at early stages of evolution the large spectrum of comparatively simple natural molecules has a hormone-like action. 相似文献
14.
中国独龙族与莽人的体质特征 总被引:8,自引:2,他引:6
在云南省贡山县独龙江乡调查了200例(男为97例,女为103例)独龙族人的体质,在金平县金水河镇调查了56例(男33例,女23例)莽人的体质,计算了体质指数,统计了指数分型情况。研究结果显示:1)独龙族、莽人体质特征接近,并与侗、拉祜、彝、德昂族较为一致。2)在蒙古人种南亚类型诸人群中,独龙族、莽人眼内角间宽值较大,而其他多数指标值偏小。3)独龙族男女均以高头型、狭头型、中胸型、中骨盆型率最高。男性还以中头型、狭面型、中鼻型、长躯干型、中腿型、宽肩型率最高。女性还以圆头型、阔面型、狭鼻型、中躯干型、亚短腿型、窄肩型率最高。4)莽人男女均以中头型(头长宽指数)、高头型、中鼻型、中腿型、中胸型、宽肩型、中骨盆型率最高。男性还以中头型(头宽高指数)、阔面型、长躯干型率最高。女性还以狭头型、中躯干型率最高。女性超阔面型率与阔面型率相等。5)独龙族与莽人蒙古褶率低,鼻根高度较低、鼻宽值多大于我国蒙古人种北亚类型诸人群。 相似文献
15.
应用植物解剖学、组织化学及植物化学方法对白鲜营养器官根、茎、叶的结构及其生物碱的积累进行了研究。结果显示:(1)白鲜根的次生结构以及茎和叶的结构类似一般双子叶植物;白鲜多年生根主要由周皮、次生韧皮部、维管形成层以及次生木质部组成,根次生韧皮部中可见大量的淀粉、草酸钙簇晶、韧皮纤维以及油细胞;茎由表皮、皮层、维管组织和髓组成;叶由表皮、栅栏组织、海绵组织和叶脉组成;在茎和叶初生韧皮部的位置均分布有韧皮纤维,在叶表皮上分布有头状腺毛和非腺毛;在茎和叶紧贴表皮处分布有分泌囊。(2)组织化学分析结果显示:在白鲜多年生根中,生物碱类物质主要分布在周皮、次生韧皮部、维管形成层和木薄壁细胞中;在茎中,生物碱主要分布在表皮、皮层、韧皮部、木薄壁细胞及髓周围薄壁细胞中;在叶中,生物碱主要分布在表皮细胞、叶肉组织和维管组织的薄壁细胞;此外在分泌囊和头状腺毛中亦含有生物碱类物质。(3)植物化学结果显示,秦岭产白鲜根皮/白鲜皮、根木质部、茎和叶中白鲜碱含量分别为0.041%、0.012%、0.004%和0.002%,其中木质部中白鲜碱含量和其他部分地区白鲜皮中白鲜碱含量类似。研究表明,在秦岭产白鲜营养器官中,除根皮/白鲜皮外,在根木质部亦含有大量的白鲜碱,且在茎和叶中亦含有一定的白鲜碱,具有潜在的开发利用价值。 相似文献
16.
洞庭湖流域中上游地区景观格局变化的水文响应 总被引:3,自引:0,他引:3
将洞庭湖流域中上游地区1980、1995和2000年的Landsat MSS和TM卫星照片解译所得的景观数据,与经过最大似然估计法“消噪”的湘、资、沅、澧四水入湖水文站的年内最高洪峰水位、最大瞬时流量、年入湖径流量和年入湖泥沙量数据进行Paneldata模型处理,并对处理后的景观和水文数据进行灰色分析和主成分分析。结果表明:研究区最高洪峰水位的变化受景观格局变化影响最大,入湖泥沙量的变化受景观格局变化影响最小。对最高洪峰水位变化影响最大的是山地水田、水库坑塘和灌木林地疏林地景观面积的变化,影响指数值分别达-48.5、-48.1和45.2;对最大瞬时流量变化影响最大的是水库坑塘、水田(山地水田除外)和灌木林地疏林地景观面积的变化,影响指数值分别达-41.9、41.2和41.2。有林地景观因林分差和林种结构单一,对各水文特征指标变化的影响较小,影响指数值分别仅为-10.1、-13.5和-14.5。 相似文献
17.
基于生态系统服务视角的山水林田湖草生态保护与修复——以洞庭湖流域为例 总被引:2,自引:0,他引:2
山水林田湖草系统保护与修复的重要目标是维护和提升区域生态系统服务。基于山水林田湖草生命共同体理念,以维护和提升人类福祉所需的重要生态系统服务为目标,提出生态系统服务视角下的山水林田湖草系统治理框架,以实现流域生态系统整体保护、质量提升和格局优化。基于该框架,以洞庭湖流域为例,通过流域生态系统格局、生态系统质量状况分析、流域生态系统服务重要性评估和生态问题识别,构建流域生态安全格局,为实现可持续的山水林田湖草生命共同体提出系统保护与修复布局建议。通过洞庭湖流域的分析案例为流域山水林田湖草生态保护与修复重要区域的识别提供了可借鉴的指标和定量分析方法,为流域尺度构建生态安全格局、实现山水林田湖草系统保护和修复提供思路和途径。 相似文献
18.
中国生态保护政策发展历程及其演进特征 总被引:1,自引:0,他引:1
生态环境是人类社会生存和发展的基础,建设生态文明是中华民族永续发展的千年大计。伴随着环境保护事业和生态文明制度体系的发展完善,生态保护政策制度体系发生着显著变化。通过对党和国家的重大决定、重要会议及政策法规文件的广泛调研和梳理,重点从基本国策确立、生态保护观念转变和政策制度变迁等3个方面,分析了我国生态保护政策发展历程及其演进特征。节约资源和保护环境基本国策的确立,是生态保护政策制度体系之根基。从生态保护思想启蒙阶段将生态保护纳入经济社会发展计划,到可持续发展阶段将生态保护作为文明发展道路的内在要求,再到生态文明阶段将人与自然视为生命共同体,这些生态保护观念的转变是生态保护最根本的政策,对于形成生态友好的社会经济发展政策和开发利用自然行为具有决定性作用。纲领性政策、生态空间管控政策、生态补偿政策、责任追究政策等生态保护政策制度的制订实施,是在客观判断我国当时基本国情基础上对生态保护观念的实践,对于推动生态保护事业发展、保障国家生态安全和社会经济高质量发展起到了关键作用。 相似文献
19.
英德西南旅游区水源河流水质与浮游生物群落特征 总被引:1,自引:0,他引:1
通过野外采样及实验室分析,调查了英德市西南旅游区水源河流上、中、下游的水质状况及浮游生物的多样性。结果表明,(1)英德市西南旅游区上、中、下游河段亚硝酸盐、氨、硝酸盐、总氮、镉、铅、铬、镍、铜、锌的含量低于国家标准,铝、钙、钴、铁、钼、硒的含量超过国家标准,而总磷、砷、镁、锰的含量在部份区段已超过国家标准;(2)浮游动物种类的个体数在整条河中以桡足类最多,上游通天岩中浮游动物个体数最多,下游碧落湖浮游动物多样性最低;此次调查总共发现68种浮游植物,其中主要集中在下游碧落湖,在中游碧落洞绿藻、蓝藻、硅藻总个体数最低,上游通天岩绿藻及甲藻总个体数最多,而下游碧落湖的蓝藻和硅藻的总个体数最多;(3)总氮、总磷、铅、钙、浮游动物Shannon-Weaver指数与浮游植物Shannon-Weaver指数从上游向下游增加,而锰与镍含量则成相反趋势。文中探讨了水中元素之间、元素与生物之间、浮游动植物之间的相互关系。本文对风景区水源的生态环境的研究风景区旅游资源开发与管理提供参考。 相似文献
20.
红树植物种质与种苗生产是所有红树林生态恢复工程的基础.本文根据工程实践并结合已有研究资料,采用聚类分析等方法,对中国红树植物资源现状与苗木繁育关键技术进行初步分析.结果表明:中国红树群落可分为低温广布型、广布型、嗜热广布型和热带分布型4种类型;资源分布可划分为琼东沿海、北部湾沿海、珠江口至粤东沿海、闽南和台湾沿海、闽东至浙南沿海5个区域.其中,北部湾沿海红树林种质资源占全国的75.3%.目前中国红树植物苗木种类开发利用率为52.6%,以胎生红树植物为主.红树林苗木生产应注意繁育方法、种实采集与储存、育苗方式、水分和盐度选择、病虫害防治及越冬防寒措施6个技术环节.结合调查和生产实践,归纳分析了中国现有5种红树林苗圃类型(旱地设施苗圃、红树林滩涂苗圃、光滩苗圃、基围塘苗圃和米草滩涂苗圃)的结构和用途特点,为红树林生态恢复工程的系统集成管理提供参考. 相似文献