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1.
Trends Plant Sci ; 28(7): 731-733, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37188556

RESUMO

China has an in situ conservation system built around national parks, and has begun establishing an ex situ conservation system led by National Botanical Gardens. We highlight how this National Botanical Gardens system will serve the global biodiversity conservation goal of harmonious coexistence between humans and nature.


Assuntos
Conservação dos Recursos Naturais , Desenvolvimento Sustentável , Humanos , Plantas , Biodiversidade , China
2.
Sci Total Environ ; 852: 158546, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36067860

RESUMO

Although tropical and subtropical regions have replaced temperate regions as the global-change hotspots for increased atmosphere nitrogen (N) deposition, whether the regional forests reach N saturation is still unclear. Understory or floor N addition has been commonly used in N-deposition studies, but the results of such studies have recently been challenged because they fail to account for canopy interception, assimilation, and leaching processes. Here, we conducted a field experiment to quantify the effects of over-canopy and understory N addition on N budgets in a lower subtropical monsoon evergreen broadleaved (LSMEB) forest. We found that the LSMEB forest was not N saturated after receiving additional N at 25 and 50 kg ha-1 yr-1 for 6 years. Plants were able to absorb the added N by increasing the N concentrations in their organs, with 120-412 % increasing trend of plant N pools under N-addition treatments. Canopy absorption of N resulting from over-canopy N addition led to increases in N concentrations in tree organs but not to increases in tree biomass. Understory N addition could underestimate the effects of N deposition in forests due to neglecting canopy N interception and canopy effects on N redistribution. Additional experiments using over-canopy N addition are needed to assess the true effects of N deposition on different forest ecosystems in different climate zones.


Assuntos
Ecossistema , Nitrogênio , Nitrogênio/análise , Florestas , Árvores , Clima , Plantas , Solo
3.
J Hazard Mater ; 411: 125029, 2021 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-33453669

RESUMO

Hydrogels have extensively studied as adsorbents, raw materials for the preparation of adsorbent hydrogels have low strength, while high strength hydrogels have weak adsorption capacity. In this study, PVA hydrogel was crosslinked via trihydroxy melamine and epichlorohydrin, and ß-cyclodextrin with strong adsorption capacity was added to remove the heavy metal ions. Results showed that the addition of trihydroxy melamine with 8%, the compressive strength of the hydrogel was increased by approximately 20%. The Langmuir isotherm model showed that the adsorption capacity of the hydrogel for Pb(II) and Ni(II) reached 505.9 mg/g and 286.7 mg/g, respectively, and the efficiency of removing the low-concentration heavy metal ions in water more than 99%. The hydrogel is low cost, and maintained highly removal efficiency under low pH. The removal efficiency of the hydrogel remained above 90% after five repeated adsorption-desorption experiments. The hydrogels have a potential to be used in wastewater treatment as adsorbents.

4.
Nature ; 559(7713): 193-204, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29995865

RESUMO

China has responded to a national land-system sustainability emergency via an integrated portfolio of large-scale programmes. Here we review 16 sustainability programmes, which invested US$378.5 billion (in 2015 US$), covered 623.9 million hectares of land and involved over 500 million people, mostly since 1998. We find overwhelmingly that the interventions improved the sustainability of China's rural land systems, but the impacts are nuanced and adverse outcomes have occurred. We identify some key characteristics of programme success, potential risks to their durability, and future research needs. We suggest directions for China and other nations as they progress towards the Sustainable Development Goals of the United Nations' Agenda 2030.


Assuntos
Solo , Desenvolvimento Sustentável/tendências , Agricultura , Biodiversidade , China , Conservação dos Recursos Naturais , Abastecimento de Alimentos , Florestas , Objetivos , Pradaria , Desenvolvimento Sustentável/economia , Desenvolvimento Sustentável/legislação & jurisprudência , Fatores de Tempo , Nações Unidas , Água
5.
J Clean Prod ; 158: 367-379, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30294072

RESUMO

Lotus (Newnbo nucifera, Gaertn) is the most important aquatic vegetable in China, with a cultivation history of over 3000 years. The emergy, energy, material, and money flows of three lotus root cultivation modes in Wanqingsha, Nansha District, Guangzhou, China were examined using Energy Systems Language models and emergy evaluation to better understand their ecological and economic characteristics on multiple spatial and temporal scales. The natural resource foundations, economic characteristics and sustainability of these modes were evaluated and compared. The results showed that although all three modes were highly dependent on purchased emergy inputs, their potential impacts as measured by the local (ELRL) and global (ELRW) environmental loading ratios were less than 1.2 and 0.7, respectively. The lotus-fish mode was the most sustainable with its emergy index of sustainable development (EISD) 2.09 and 2.13 times that of the pure lotus and lotus-shrimp modes, respectively. All three lotus-root production modes had superior economic viability, since their Output/Input ratio ranged from 2.56 to 4.95. The results indicated that agricultural systems may have different environmental impacts and sustainability characteristics at different spatial and temporal scales, and that these impacts and characteristics can be simultaneously explored using integrated emergy and economic evaluations.

7.
J Environ Manage ; 91(12): 2727-35, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20702024

RESUMO

China is the largest rice producing and consuming country in the world, but rice production has given way to the production of vegetables during the past twenty years. The government has been trying to stop this land-use conversion and increase the area in rice-vegetable rotation. Important questions that must be answered to determine what strategy is best for society are, "What is the reason behind this conversion?"; "Which system is more productive and which is more sustainable?"; and "How can economic policy be used to adjust the pattern of farmland use to attain sustainable development?" To answer these questions, a combined evaluation of these agricultural production systems was done using emergy, energy and economic methods. An economic analysis clearly showed that the reason for this conversion was simply that the economic output/input ratio and the benefit density of the vegetable production system were greater than that of rice. However, both energy and emergy evaluations showed that long-term rice was the best choice for sustainable development, followed by rotation systems. The current price of rice is lower than the em-value of rice produced from the long-term rice system, but higher than that of rice produced from the rotation system. Scenario analysis showed that if the government increases the price of rice to the em-value of rice produced from the long-term rice system, US$0.4/kg, and takes the value of soil organic matter into account, the economic output/input ratios of both the rice and rotation systems will be higher than that of the vegetable system. The three methods, energy, emergy and economics, are different but complementary, each revealing a different aspect of the same system. Their combined use shows not only the reasons behind a system's current state or condition, but also the way to adjust these systems to move toward more sustainable states.


Assuntos
Agricultura/economia , Conservação dos Recursos Naturais , Produtos Agrícolas/economia , Oryza , Verduras , Agricultura/legislação & jurisprudência , Agricultura/tendências , China
8.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 16(3): 155-7, 2004 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-15009962

RESUMO

OBJECTIVE: To explore the effect of different starting time of thrombolysis on acute myocardial infarction (AMI). METHODS: Ninety-five patients of AMI were divided into prompt thrombolysis group (less then 6 h, 46 patients) and delayed thrombolysis group (6-12 hours, 49 patients), according to the different starting time of treating AMI. The incidences of reopening and side-effect, as well as mortality were compared between two groups. RESULTS: The reopening rate and mortality in prompt thrombolysis group were 76% and 4%, respectively. The reopening rate and mortality in delayed thrombolysis group were 49% and 12%, respectively. Compared the prompt thrombolysis group with the delayed thrombolysis group, there was a significance discrepancy (both P<0.01). The side-effect rate had not significant discrepancy (15% vs. 16%, P>0.05). CONCLUSION: The clinical reopening rate of the thrombolysis is higher in patients with thrombolysis less than 6 hours, the mortality is lower. The thrombolytic treatment should be prompt for patients adapting thrombolysis.


Assuntos
Infarto do Miocárdio/tratamento farmacológico , Terapia Trombolítica/métodos , Adulto , Idoso , Esquema de Medicação , Hipersensibilidade a Drogas/etiologia , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Hipotensão/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Taxa de Sobrevida , Terapia Trombolítica/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
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