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1.
全面客观评价生态资源承载能力,进而为区域可持续发展提供理论依据。以甘肃省迭部县为例,首先,采用压力-状态-响应(P-S-R)模型构建生态承载力评估指标体系,运用层次分析法(Analytic Hierarchy Process,AHP)确定各指标权重,评估生态环境承载力现状;其次,在生态功能区层面对迭部县水源涵养功能及生物多样性功能进行评价;最后,对生态承载力状况进行成因解析。研究结果表明:(1)迭部县整体生态承载力得分为0.239,处于“较强”承载力状态,构成整体生态承载力的生态弹性力、资源和环境承载力和人类社会影响力得分分别为0.222、0.062和0.063。(2)2016年,迭部县单位面积水源涵养量为111.76 mm,水源涵养功能处于“高”状态,其中,水源涵养功能较高地区主要集中在以草地和针阔混交林为主的区域。(3)自然栖息地面积占迭部县总面积的83.67%,其自然栖息质量指数(Natural Habitant Quality Index,NHQI)处于“高”状态。(4)从自然和经济2个因素进行分析,发现迭部县生态环境条件较好,但林草地面积已呈现出逐渐减少状态,因此需要通过合理科学的开发引导,发展文化旅游事业,推动迭部县的可持续发展。 相似文献
2.
S. Zduczyk A. Domaszewski Z. Giiejewski T. Janowski A. Zebracki 《Reproduction in domestic animals》1989,24(1):1-7
Inhalt: An 81 Versuchs- und 92 Kontrolltieren der Rasse “Potnische Schwarzbunte” aus 3 Problembetrieben wurde ein Versuch zur Sterilitätsprophylaxe rnit der PRID-Spirale durchgeführt. Anhand klinischer Befunde und Milchprogesteronwerten wurde die Untergruppe aus Kühen mit Ovardystrophie (18 Versuchs- und 22 Kontrolltiere) gebildet und extra ausgewertet. Der Behandlungsbeginn lag zwischen 60 und 80 Tage post partum. Die Versuchstiere wurden mit der PRID-Spirale 12 Tage lang behandelt, die Kontrolltiere erhielten Injcktionen rnit Kochsalzlösung und solche rnit Ovardystrophie wurden zusätzlich mit einer Eierstocksmassage behandelt. Die Versuchstiere wurden 56 und 72 Stunden nach Entfernung der Spirale blind besamt. Die Brunstin-duktionsrate betrug insgesamt 90,1%, bei denen rnit Ovardystrophie 77,7%. Die An-wendung der PRID-Spirale führte zur Verbesserung der Fertilitätslage. Die Gesamt-trächtigkeitsrate lag mit 87,6% bei den Versuchskühenüber derjenigen der Kontrollkü-he mit 79,3%. Die Behandlung der Tiere rnit Ovardystrophie erbrachte eine Gesamt-trächtigkeitsrate von 88,8% bei den Versuchs- und 72,7% bei den Kontrolltieren. Die Zwischentragezeit betrug bei den Versuchstieren 101,2 Tage und bei den Kontrolltieren 113,3 Tage (p ≤ 0,05). Bei den azyklischen Tieren lag die Zwischentragezeit bei 104,6 Tage bzw. 134,7 Tage (p ≤ 0,05). In einem anderen Versuch wurde 20 Hybriden zwischen Wisent und Hausrind rwecks Zyklussynchronisation die PRID-Spirale verabreicht. Die Brunstinduktionsrate betrug 66,6%, das Erstbesamungsergebnis nach Doppelbesamung 30%, die Gesamtträchtig-keitsrate nach dem Decken der umrindernden Kreuzungstiere rnit einem Bullen 90%. Die Deckperiode konnte verkürzt werden. Contents: Investigations on the synchronization of estrus cycle in cattle from farms with fertility problems and in cross-breeds between bison and cattle with a PRID-de-vice In 81 experimental and 92 control animals of the “Polish Black and White” breed derived from 3 farms with fertility problems an investigation was carried out for sterility prophylaxis using the PRID-device. Based on clinical findings and milk progesterone values cattle with ovarian dystrophy (18 experimental and 22 control animals) from a special group were used. The begin of treatment was between 60 and 80 days post partum. All experimental animals had received a PRID-device for a duration of 12 days. Control animals were injected with physiological saline solution and animals with ovarian dystrophy were treated additionally with ovarian massage. Experimental animals were inseminated 56 and 72 hrs after removal of the device. All animals taken, estrus was induced in 90.1% of the animals, while only 77.7% of animals with ovarian dystrophy came to estrus. Application of the PRID-device led to an improvement of fertility. Pregnancy rates in experimental animals were 87.6%, while only 79.3% of the control animals were pregnant. Treatment of animals with ovarian dystrophy resulted in 88.8% pregnancies for treated and 72.7% for control animals. Experimental animals were non-pregnant for a duration of 101.2 days, while control animals remained non-pregnant for 113.3 days (p < 0.05). Acyclic cattle had a non-pregnant period of 104.6 days and 134.7 days (p < 0.05) respectively. In a second experiment 20 cross-breeds between bison and domestic cattle were treated with a PRID-device for synchronization of the estrus cycle. The rate of estrus induction was 66.6%, the fertility after double insemination 30%, the total pregnancy rate improved after mating with a bull of animals that had not conceived to 90%. 相似文献
3.
G. S. Z. Ssenyonga I. Kakoma Sonia Montenegro-James R. Hansen 《Tropical animal health and production》1992,24(1):2-8
Summary The suitability of blood collected on filter papers in comparison with corresponding conventional serum samples in the diagnosis
of bovine anaplasmosis was studied using the complement fixation test, DOT-ELISA, Western immunoblot and rapid card agglutination
test. Dried blood on Whatman filter paper no. 1 was eluted in PBS 0·05% Tween 20 giving an initial dilution of 1∶10.
The reactivity of the eluted samples in both DOT-ELISA and Western immunoblotting were similar to those obtained with the
corresponding straight serum sample dilutions. Filter paper samples gave lower reactivity in the remaining tests when compared
with corresponding serum samples. There was no significant difference in the reactivity between the eluates from filter papers
stored at temperatures ranging between 15·5 and 24°C and those kept refrigerated. Storage at 15·5 to 24°C did not significantly
affect reactivity for up to six months. Eluates from filter papers stored for six months at 15·5 to 24°C continued to give
similar reactivity as those from freshly prepared filter papers in both DOT-ELISA and Western blot, and in the rapid card
agglutination test.
It is concluded that collecting blood on filter papers is a suitable technique for large scale seroepidemiological studies
on anaplasmosis and offers many advantages in developing countries where transport and cold chain facilities are a major constraint.
Resumen Se estudió la efectividad de muestras de sangre colectadas en papel filtro, en comparación con las correspondientes muestras convencionales du suero, en el diagnóstico de anaplasmosis bovina, utilizando fijación de complemento, DOT-ELISA, Western, immunoblot y la prueba rápida de la tarjeta. La sangre seca en papel Whatman No 1 fue removida con PBS 0·05% entre 20, dando una dilución inicial de 1∶10. La reactividad de las muestras removidas de papel filtro, en la prueba de DOT-ELISA y Western immunoblotting, fueron similares a la obtenida con la correspondiente muestra de suero. Las muestras de papel filtro reaccionaron menos en las otras pruebas, cuando se compararon con las correspondients muestras du suero. No hubo diferencia significativa en la reactividad entre los lavados del papel filtro guardados a temperaturas entre 15·5 y 24°C y aquellos guardados en refrigeración. El almacenaje entre 15·5 y 24°C, no afectó la reactividad hastas seis meses. Los lavados de papel filtro guardados por seis meses entre 15·5 y 24°C, dieron la misma reactividad como los lavados frescos, en la prueba DOT-ELISA y Western blot, lo mismo que en la prueba de aglutinación rápida de tarjeta. Se concluye, qu la colección de sangre en papel filtro, es una buena técnica para estudios epidemiológicos de cierta magnitud, sobre anaplasmosis, ofreciendo ventajas considerables en paises en desarrollo en donde las cadenas de frío son deficientes.
Résumé La fiabilité du sang récolté sur papier filtre comparée à celle des prélèvements conventionnels de sérum pour le diagnostic de l'anaplasmose a été étudiée à l'aide des tests suivants: fixation du complément, ELISA, immunoblot de Western, test rapide d'agglutination sur carte. Du sang séché sur papier filtre Whatman No 1 a fait l'object d'une élution dans une solution de PBS à 0,05 p. 100 (Tween 20) pour donner une dilution de base au dilution de base au 1∶10. Le réactivité des échantillons, autant avec le test ELISA que l'immunoblot Western, a été identique à celle obtenue par dilution directe de sérums homologue. Les échantillons sur papier filtre ont donné une réactivité plus faible pour les autres tests, comparée à celle des échantillons de sérum semblables. Aucune différence significative n'a été décelée quant à leur réactivité les éluats provenant de papiers filtres stockés à des températures comprises entre 15,5 et 24°C at ceux conservés au réfrigérateur. Le stockage entre 15,5 et 24°C n'a pas non plus affecté la réactivité de fa?on significative; les éluats conservés à partir des papiers filtres, à cette même température durant 6 mois, ont montré des réactions identiques que ceux provenant de papiers filtres fra?chement préparés, à la fois avec le test ELISA, celui de Western Blot et le test d'agglutination rapide sur carte. On peut conclure que la collecte du sang sur papier filtre est une technique adaptée à l'étude épidémiologique de l'anaplasmose à grande échelle. Elle offre de nombreux avantages dans les pays en développement où offre de nombreux avantages dans les pays en développement où les moyens de transports et la cha?ne du froid constituent des contraintes majeures.相似文献
4.
用微量热法测定了剌槐种子的萌发热谱,发现其产热规律与其吸水规律和呼吸规律相关,并获得了衡量种子活力4个参数。 相似文献
5.
6.
水资源核算及对GDP的修正——以中国东部经济发达地区为例 总被引:1,自引:0,他引:1
对中国东部经济发达地区水资源核算的结果表明 ,以GDP为主要衡量指标的现行国民经济核算体系过高地估计了该地区经济的发展水平。扣除水资源价值损失 ,1994~ 1997年区域GDP平均下降 5 5 8% ,这意味着东部经济发达地区经济增长存在着较为严重的环境负债 相似文献
7.
A field experiment was conducted with different nitrogen regimes to assess the growth and yield performance of wheat genotypes which differ in nitrate assimilation potential. Genotypic differences in biomass accumulation were observed at different growth stages. The nitrogen treatment had little effect on biomass accumulation at early stages of growth, while at later stages of growth there was enhanced biomass accumulation when N was applied in more than two splits. On an average, genotypes with high nitrate reductase activity (the 'HNR' genotypes) accumulated 14.2 % more biomass than the genotypes with low nitrate reductase activity ('LNR' genotypes) when an extra dose (40 kg N ha−1 ) of nitrogen was given at the time of anthesis. The application of nitrogen in more than two splits increased grain yield of both 'HNR' and 'LNR' genotypes mainly by increasing grain weight per ear. The application of an extra dose of nitrogen (40 kg N ha−1 ) at the time of anthesis increased grain yield of 'HNR' genotypes by 38.5 % as compared to 'LNR' genotypes. 相似文献
8.
Components of the energy and heat balances were examined in two maize hybrids grown at three different plant densities (40, 70 and 100 thousand plants per hectare). One of the hybrids was drought tolerant, while the other was bred for cultivation under irrigated conditions. An increase in plant density influenced not only the size of the leaf area, but also the distribution of the leaves at various plant heights. The extinction coefficient, which provides a quantification of radiation penetration, was higher in the irrigated treatments. By contrast to the other two treatments, the plant canopy in the thinly sown stands remained open throughout the vegetation period, and thus behaved quite differently to the closed stands, making it impossible to compare them. Smaller albedo values were recorded for the hybrid bred for irrigation and in thinly sown stands. The low plant density allowed more energy to reach the soil, from which it was reflected, making a considerable contribution to the final temperature in the stand. The latent heat, in keeping with the quantity of water transpired, was the greatest in the densely sown stands. There was little difference between the latent heat values of the normal and dense stands in either hybrid, indicating that they both had a similar sensitivity to increased stand density. If sufficient water is available it would appear that the stand density could be increased even for the drought-tolerant hybrid. 相似文献
9.
Significant differences of callus induction, green plant regeneration and culture efficiency were observed among restorer lines and their hybrids in rice. Average callus induction percentage of F1, hybrids was about twice that of their parents. Twenty doubled haploid (DH) lines that showed normal fertility with both indica and japonica CMS lines, were selected as widely compatible restorers (WCRs). TG8 derived from CPSLO17/Minghui 63 not only showed normal fertility to both indica and japonica test varieties and CMS lines, but also exhibited superior agronomic traits, in particular short plant, desired plant type, high tillerability, large panicles, good grain quality and resistance to rice blast disease. Strong heterosis for yield was observed in crosses between indica or japonica CMS lines and TG8. TG8 possessed a dominant, widely compatible gene (WCG) that was inherited from the variety CPSLO17. Results confirmed that the anther culture technique is a quick and effective way of developing widely compatible restorers in rice and that it is applicable to the direct use of intersubspecific heterosis with the three-line method. 相似文献
10.