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101.
深圳市西海岸和海域生物资源多样性的管护 总被引:3,自引:0,他引:3
王献溥 《植物资源与环境学报》1992,1(1):1-5
本文着重介绍生物多样性管护区的基本含义和要求,结合深圳市西海岸和海域的特点,提出建立珠江口南海海岸和海洋生物多样性管护区,以发挥该区域的资源优势和持续利用,为建设深圳特区做出应有的贡献。 相似文献
102.
Julia F. Morton 《Economic botany》1991,45(3):318-333
The horseradish tree (Moringa pterygosperma,) is being introduced into drought-ridden lands to augment the local food and
fodder supply. The tree grows up to 5 m per year. The foliage is high in calcium and has half the oxalates of amaranth. Seeds
yield edible oil and the seed meal is used as fertilizer and as a coagulant to clarify turbid water. The philanthropic center,
ECHO (Educational Concerns for Hunger Organization), North Fort Myers, Florida, receives many requests for seeds. A missionary
in Mali wrote: “The seeds you sent arrived during the worst year of 14 years of dry weather. Only the moringa survived, and
they have flourished. ”Another seed shipment resulted, after harvesting a crop, in 25 000 trees being planted by university
students and faculty, around laborers’ houses in Maranhao, Brazil. The tree is not limited to tropical lowlands, but thrives
at elevations of 800-1200 m in protected mountain areas of southern Mexico. The long-range effects of ingesting various parts
of the tree as food or folkmedicine need study. Attention should be given to horticultural improvement, perhaps through hybridization
with one or more related species now being compared with M. pterygosperma in India and Africa.
ХРеНовое дерево, Moringa pterygosperma F. Gaertn. (Moringaceae), Дар сыхим землям. Хреновое дерево, Moringa pterygosperma,
вводится в бездождивые землии чтоб умножить местное снабжение пищи и корма. Дерево растет до 5 метров в год. Листья содержат
много кальцию и половину щавелев по сравнени#x044E; с амарантом. Семя дают съедобное масло и семеная мука употребляется как
одобрение и как коагулант для очищение мутной воды. Филантропический цэнтэр ECHO (Educational Concern for Hunger Organization,
North Fort Myers, Florida) полужает мното просьб чтоб получить семя. Один миссионер из Мали писал “Семя которые вы послали,
прибыли в самый сухой год за 14 лет сухой погоды. Только моринга пережила и цвела. Другая отправка семен была совершена после
получения урожая и 25000 деревьев были посажены студентами и учителями около домов рабочих в Маранхау, Брразилия.
Это дерево не ограаничевается тропическим климатом и преуспевает на уровне 800 до 1200 метров в защищенных горных местах южной
Мексики. 相似文献
103.
Tokuo Ogawa Junichi Sugenoya Norikazu Ohnishi Keiko Natsume Megumi Ochiai Motohiko Nishida Norihiko Shinoda Kenichi Katoh Ritsuko Imamura 《International journal of biometeorology》1991,35(1):18-23
In an attempt to detect differences in the thermal effect of infrared irradiation of different wavelengths, transient sweating response to infrared irradiation in various spectral regions was examined. In Series 1, the ventral or dorsal surface of the nude subject was irradiated repetitively for a period of 4 min (2 min on, 2 min off) by each of three kinds of infrared heaters with main emissivity in near-infrared (NIR; 0.7–2.8 m), intermediate-infrared (MIR; 1.5–5.8 m), and far-infrared (FIR; 2.8–25 m) regions. The sweating response on a non-irradiated area tended to be the greatest with MIR, while the magnitude of the sweating response on the irradiated area showed no consistent differences among various wavelengths. The results infer that MIR stimulated cutaneous thomoreceptors most effectively, while its direct effect on local sweat gland activity was minimal. In Series 2, the effects of 9–12 min irradiations in more restricted ranges of wavelength were compared by the combination of the three kinds of heaters with filters (translucent to wavelength ranges of 1.3–2.7, 2.7–3.5, 3.6–8.0 m, respectively). The sweating response on a remote area was predominantly greater with the range of 2.7–3.5 m than with the other wavelength ranges, while the local effect on sweating was minimal with this range. The results of Series 2 reinforce those of Series 1, indicating that the degree of stimulation of cutaneous thermoreceptors and of direct thermal effect on sweat gland activity differ with spectral regions incident on the skin, thus affecting local and remote effects on the sweating response. 相似文献
105.
黄土丘陵半干旱区不同作物生态效能研究 总被引:5,自引:0,他引:5
深入研究特定生态环境条件下不同作物生产力及其生态效能,对于合理调控农田生态系统,探讨提高系统生产力途径具有重要意义。60年代以来,在国际生物学计划(IBP)的影响下,美国、日本、菲葎宾等国先后进行了小麦、水稻、大豆等作物农田生态效能研究。我国于“六·五”期间分别在南方稻区、黄淮海平原以及北方灌区等不同农业区开展了多种作物种植制度生产力问题研究,并取得重 相似文献
106.
Bayesian analyses for a multiple capture-recapture model 总被引:3,自引:0,他引:3
107.
108.
A simple method for shortening a plasmid genome using a system of plasmid cointegration mediated by a Tn3 mutant 总被引:3,自引:0,他引:3
This paper describes a simple method for the isolation of small plasmids of various sizes from pSMI, a derivative of the resistance plasmid R 100. The method is based on the observation that a repressor-negative mutant of the ampicillin-resistance (ampr) transposon Tn3, Tn3 No. 5, mediates cointegration of a plasmid carrying Tn 3 No. 5 (pMB8::Tn 3 No. 5) into virtually any site on pSMI. The resulting cointegrate plasmids contain the pSMI sequence which is joined with the ampr gene of the Tn 3 mutant. This cointegration is so frequent that large cointegrate plasmids can be readily detected in the total plasmid DNA prepared from cells carrying pSMI and pMB8::Tn3 No. 5. We were able to isolate small plasmids of various sizes by digesting the total plasmid DNAs with restriction endonucleases which cut both pSM 1 and Tn3 No. 5 sequences present in the cointegrates and subsequently ligating the restriction fragment containing both the ampr gene and the region necessary for replication of pSMI. Analysis of these plasmids, named pBV plasmids, with restriction endonucleases and by nucleotide sequencing allowed us to determine regions necessary or unnecessary for replication, thus defining a minimal replication region of pSMI. The present method is generally useful for the isolation of small derivatives from any large plasmid for the study of genes and sites adjacent to or within the minimal replication region of the plasmid. 相似文献
109.
110.
Data on the occurrence of species with fleshy diaspores and on breeding birds were collected in three abandoned orchards, resp. 8, 11 and 24 years after abandonment. Most of the 41 phanerophytes and vines with fleshy diaspores are also found in the borders of the orchards, the more so if the number of years since abandonment increases. Most species have small seeds and red or black coloured diaspores, most of which ripen in autumn. The frequent species show a characteristic distribution pattern in relation to the distance of the fruit trees: high densities near the trunk and uniform decrease with distance. This is explained by the behaviour of frugivorous birds. No correlation was found between distribution patterns and soil conditions. Age structure of colonizing species shows a distribution conforming an inversed J curve in the more recently abandoned orchard. The main conclusions are:
- Pioncor trees are attractive for frugivorous birds and may act as nuclei. This supports the facilitation model.
- The distribution of diaspores by birds helps to homogenize the species distribution on the regional level but at the site level individual differences in nucleation cause a heterogeneity.