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111.
Ecosystems are facing severe destruction and threats due to unreasonable human utilization. Repairing damage to nature and protect biodiversity through ecological compensation will be an inevitable measure for achieving sustainable development. To explore the current research hotspots and future research directions of ecological compensation, this paper tries to search the WoS Core Collection and collects 685 ecological compensation papers published between 1990 and 2020. R language and CiteSpace software were applied in this paper. It is found that: (1) The number of articles has gone through the initial explorations, fluctuating growth, and rapid development of the field from 1990 to 2020. Only 7.5% of authors have published more than two papers. (2) Regarding the production of papers, the top 3 countries are the US, China, and the UK. At present, the majority of countries focus on independent research, and international cooperation is gradually strengthening. (3) The current research hotpots mainly invlove biodiversity and sustainable development, ecological compensation for forests and water resources, China's Grain-to-Green Project, poverty reduction, livelihood issues, public participation willingness and equity issues, indicating that ecological compensation is a rapidly emerging interdisciplinary academic field. (4) The results reveal several research directions in the future: strengthening theoretical research, resolving issues pertaining to the complex relationships among stakeholders, encouraging a transformation from qualitative to quantitative research, increasing the focus of ecological compensation models on local conditions, and applying more scientific models and high-tech tools in effect evaluation.  相似文献   
112.
In Iran, mangroves are located in the south of the country, where they fulfill essential ecosystem functions, but some parts of them have been destroyed for various reasons in recent years so that it seems necessary to have a management plan consistent with the conservation of this ecosystem. But, it needs knowledge of the trend of and reasons for the degradation of these forests. So, the primary idea of this research was to discover the factors involved in the degradation of these forests and how to manage them. So, the research first used the remote sensing technique to determine the rate of their degradation over the last 20 years. Then, using the Delphi technique, 45 factors were identified for the degradation of these forests and they were classified into five categories including climatic and environmental, anthropogenic, socioeconomic, psychological, and policymaking and legal. Finally, the analytic hierarchy process (AHP) was used to rank these factors within two management paradigms of remediability and preventability so that the ecosystem can be soundly managed by classifying these factors. Overall, the results can provide policymakers with new insights into forest management and the policies presented here can contribute to the sustainability of this ecosystem.  相似文献   
113.
植物受体蛋白激酶通过与胞外信号结合感知和接收外部信号传递,在植物各个生理过程及生物代谢中发挥着重大的作用。其中M/MLD类受体蛋白激酶是一类植物特有的具有Malectin-like结构域的受体蛋白激酶。研究表明,M/MLD-RLKs亚家族参与植物发育过程及生物/非生物胁迫调控。该研究对近年来国内外有关植物M/MLD-RLKs的发现、结构特点以及生物学功能等方面的研究进展进行综述,并重点阐述其在调控植物根系、叶片、花发育及响应多种胁迫过程中的作用,为深入研究M/MLD-RLKs在植物生长发育过程中的生理功能提供参考。  相似文献   
114.
姚保民  曾青  张丽梅 《生物多样性》2022,30(12):22353-254
原生生物广泛分布在土壤和不同生境中, 其数量庞大、种类繁多, 在生态系统物质循环和能量流动以及维持土壤和植物健康中起着举足轻重的作用。与土壤其他生物类群相比, 原生生物分类体系和生态类型复杂, 分类鉴定困难且分子检测技术不够成熟, 目前对原生生物的认识相对不足。本文对当前原生生物的相关研究进展进行了总结和梳理, 系统阐述了原生生物的分类系统和营养功能群特征、土壤原生生物的多样性分布特征及影响因子, 重点介绍了原生生物群落在参与土壤养分循环、维持土壤和植物健康等中的功能作用, 并对未来的研究方向与应用前景进行了展望。对土壤原生生物的研究有助于我们深入认识土壤生物多样性资源, 并进行保护性地开发和利用, 维护土壤和生态系统健康。  相似文献   
115.
《Journal of Asia》2022,25(3):101956
The beet armyworm, Spodoptera exigua (Hübner, 1808) and the Egyptian cotton leafworm, S. littoralis (Boisduval, 1833), are amongst the most notorious agricultural pest species in Iran. Spodoptera exigua is considered a serious pest of different crops, whereas S. littoralis is known as an important pest of cotton.In this paper, the potential distribution areas of these species in Iran and the important climatic factors affecting their distribution were predicted using the MaxEnt model and the ArcGIS. The results indicate that the main environmental variables contributing to S. exigua’s distribution were precipitation of the coldest quarter (bio19), average wind speed in April (wind4), and annual precipitation (bio12). Also, minimum temperature of the coldest month (bio6), mean temperature of coldest quarter (bio11), altitude and average wind speed in May (wind5) were dominant climatic factors that affected the potential distribution of S. littoralis. These species overlapped in most parts of coastal areas in the southern and northern parts of Iran, with an average overlapping range of 33.2%. Considering their preferred host plants in Iran, it is necessary to strengthen biosurveillance programes and management of these two species in their suitable areas to prevent further invasion, which endangers agricultural security.  相似文献   
116.
Bacteria are known to display extensive metabolic diversity and many studies have shown that they can use an extensive repertoire of small molecules as carbon‐ and energy sources. However, it is less clear to what extent a bacterium can expand its existing metabolic capabilities by acquiring mutations that, for example, rewire its metabolic pathways. To investigate this capability and potential for evolution of novel phenotypes, we sampled large populations of mutagenized Salmonella enterica to select very rare mutants that can grow on minimal media containing 124 low molecular weight compounds as sole carbon sources. We found mutants growing on 18 of these novel carbon sources, and identified the causal mutations that allowed growth for four of them. Mutations that relieve physiological constraints or increase expression of existing pathways were found to be important contributors to the novel phenotypes. For the remaining 14 novel phenotypes, whole genome sequencing of independent mutants and genetic analysis suggested that these novel metabolic phenotypes result from a combination of multiple mutations. This work, by virtue of identifying the genetic and mechanistic basis for new metabolic capabilities, sheds light on the properties of adaptive landscapes underlying the evolution of novel phenotypes.  相似文献   
117.
Cystic echinococcosis is a chronic and complex zoonotic disease. The mechanisms underlying the parasite’s establishment, growth and persistence are not completely understood, and are thought be modulated by a crosstalk through extracellular vesicles. Here, EVs were isolated from the hydatid cyst fluid of patients with cystic echinococcosis and protoscolex culture supernatant. Proteomic analysis of these EVs revealed several parasite- and human-derived proteins. Very few studies have performed proteomic analysis of EVs isolated from HCF and PCS. Our proteomic analysis of the EVs derived from HCF and PCS facilitated identification of 1175 proteins, wherein 1026 and 38 proteins were exclusively identified in the EVs derived from HCF (HCF-EVs) and PCS (PCS-EVs), respectively, and 111 proteins were shared in both. The results of co-culture of PCS-EVs with murine peripheral blood mononuclear cells showed that PCS-EVs significantly regulated T lymphocyte functions in a dose-dependent manner. Collectively, our results provide valuable information on parasite survival strategies and new insights into the role of these EVs in the establishment and persistence of hydatid cysts.  相似文献   
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甘肃东大山自然保护区岩羊生态行为的初步观察   总被引:1,自引:1,他引:0  
2004年7月和8月,通过样线调查、野外直接跟踪观察和瞬间取样的方法,对东大山自然保护区岩羊(Pseudois nayaur)的种群结构和生态行为进行了初步研究。在观察到的720只岩羊中,719只组成了50个群,最大的群82只,最小的群2只,平均群大小(14.38±15.83)只(n=50)。雌雄性比为1∶0.63,成年雌体、亚成体和幼体之比是1∶0.4∶0.24。岩羊的昼间活动中,上午和下午各有一个瞬间觅食高峰,分别在6:30时和15:30时,中午有一段较长时间的休息期。通过对一个46只岩羊群连续12 d的野外跟踪观察,发现该岩羊群昼间的活动范围基本上在1.47 km2内。对152个自然死亡的雄性岩羊头骨的分析表明,东大山雄性岩羊的自然死亡年龄在7.5~11.5龄,其中9.5龄是其自然死亡的高峰。  相似文献   
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