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31.
We carried out an ecosystem service (ES) assessment at Soto de Pajares, a 400 ha active gravel quarry site located close to protected areas in the southeast of the Community of Madrid, Spain. The currently approved restoration plan is for quarry‐made excavations to be restored back to agricultural land. However, the site has been identified as being important for nature, so different restoration strategies should be considered. To better understand how these compare in terms of ES provision, which had not previously been done at mineral extraction sites in Spain, we used an established toolkit: the Toolkit for Ecosystem Service Site‐based Assessments (TESSA). We compared the agriculture‐focused restoration plan and two nature‐focused alternative scenarios, one without public access (conservation scenario) and the other with public access (compromise scenario). Monetary estimations of the value of agricultural production, climate change mitigation, and recreation were calculated in three scenarios. Results indicated that the compromise scenario provided the greatest annual value (€91,409), mainly due to its potential visitors, surpassing both agricultural (€68,504) and conservation (€48,556) scenarios. Considering the higher costs associated with restoring sites to agricultural production, nature conservation may be an attractive option for extraction companies. The use of TESSA at this site has provided valuable information to quarry managers to help guide their decision‐making. 相似文献
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Effects of transportation direction of photosynthate on soil microbial processes in the rhizosphere of Phyllostachys bissetii北大核心CSCD
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Aims Clonal integration contributes greatly to the adaption of clonal plants to heterogeneous habitats. However, effects of transportation direction of photosynthate on microbial processes need to be further investigated in the rhizosphere. The purpose of this study is to determine the effects of directional differences in photosynthate transport on microbial processes in the rhizosphere of clonal plant Phyllostachys bissetii. Methods By removing the aboveground parts of the ramets, acropetal treatment and basipetal treatment were applied in this study to control the transportation direction of photosynthate. In acropetal treatment, aboveground parts of distal ramets were cut off (with 20 cm above ground kept), and proximal ramets were left intact. While in basipetal treatment, aboveground parts of proximal ramets were cut off (with 20 cm above ground kept), and distal ramets were left intact. Rhizomes between the two ramets were either connected or severed. Carbon (C) and nitrogen (N) availabilities, and enzyme activities in the rhizosphere soils were measured. Important findings In acropetal treatment, total organic carbon (TOC), dissolved organic carbon (DOC), dissolved organic nitrogen (DON) and soil inorganic nitrogen (NH4 +-N and NO3 --N) content in the rhizosphere soil of distal ramets with connected rhizomes were significantly higher than those with severed rhizome. The activities of urease, polyphenol oxidase (POXase), N-acetyl-β-D-Glucosaminidase (NAGase) were significantly enhanced. Further, clonal integration had a significant effect on C and N availability, and microbial processes in the rhizosphere soil of neighbouring ramets. In basipetal treatment, clonal integration did not show a significant effect on C availability in the rhizosphere soil of proximal ramets, but microbial processes along with soil enzyme activities were altered accordingly. Effects of transportation direction of photosynthate on microbial processes in the rhizosphere of P. bissetii provides insights into the adaptation mechanisms of clonal plant populations. © 2018 Editorial Office of Chinese Journal of Plant Ecology. All rights reserved. 相似文献
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Thomas Evans Philine zu Ermgassen Tatsuya Amano Kelvin S.‐H. Peh 《Ecology and evolution》2018,8(4):1984-1994
Invasive alien species (IAS) constitute a major threat to global biological diversity. In order to control their spread, a detailed understanding of the factors influencing their distribution is essential. Although international trade is regarded as a major force structuring spatial patterns of IAS, the role of other social factors remains unclear. Despite studies highlighting the importance of strong governance in slowing drivers of biodiversity loss such as logging, deforestation, and agricultural intensification, no study has yet analyzed its contribution to the issue of IAS. Using estimates of governance quality and comprehensive spatiotemporal IAS data, we performed multiple linear regressions to investigate the effect of governance quality upon the distribution of species listed under “100 of the worst” IAS in 38 Eurasian countries as defined by DASIE. Our model suggested that for countries with higher GDP, stronger governance was associated with a greater number of the worst IAS; in contrast, for the lowest GDP countries under analysis, stronger governance was associated with fewer of these IAS. We elucidate how the quality of governance within a country has implications for trade, tourism, transport, legislation, and economic development, all of which influence the spread of IAS. While our findings support the common assumption that strengthening governance benefits conservation interventions in countries of smaller economy, we find that this effect is not universal. Stronger governance alone cannot adequately address the problem of IAS, and targeted action is required in relatively high‐GDP countries in order to stem the influx of IAS associated with high volumes of trade. 相似文献
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Neal R. Pellis Thomas J. Goodwin Diana Risin Bradley W. McIntyre Roland P. Pizzini David Cooper Tacey L. Baker Glenn F. Spaulding 《In vitro cellular & developmental biology. Animal》1997,33(5):398-405
Summary Immunity relies on the circulation of lymphocytes through many different tissues including blood vessels, lymphatic channels,
and lymphoid organs. The ability of lymphocytes to traverse the interstitium in both nonlymphoid and lymphoid tissues can
be determined in vitro by assaying their capacity to locomote through Type I collagen. In an attempt to characterize potential causes of microgravity-induced
immunosuppression, we investigated the effects of simulated microgravity on human lymphocyte function in vitro using a specialized rotating-wall vessel culture system developed at the Johnson Space Center. This very low shear culture
system randomizes gravitational vectors and provides an in vitro approximation of microgravity. In the randomized gravity of the rotating-wall vessel culture system, peripheral blood lymphocytes
did not locomote through Type I collagen, whereas static cultures supported normal movement. Although cells remained viable
during the entire culture period, peripheral blood lymphocytes transferred to unit gravity (static culture) after 6 h in the
rotating-wall vessel culture system were slow to recover and locomote into collagen matrix. After 72 h in the rotating-wall
vessel culture system and an additional 72 h in static culture, peripheral blood lymphocytes did not recover their ability
to locomote. Loss of locomotory activity in rotating-wall vessel cultures appears to be related to changes in the activation
state of the lymphocytes and the expression of adhesion molecules. Culture in the rotating-wall vessel system blunted the
ability of peripheral blood lymphocytes to respond to polyclonal activation with phytohemagglutinin. Locomotory response remained
intact when peripheral blood lymphocytes were activated by anti-CD3 antibody and interleukin-2 prior to introduction into
the rotating-wall vessel culture system. Thus, in addition to the systemic stress factors that may affect immunity, isolated
lymphocytes respond to gravitational changes by ceasing locomotion through model interstitium. These in vitro investigations suggest that microgravity induces non-stress-related changes in cell function that may be critical to immunity.
Preliminary analysis of locomotion in true microgravity revealed a substantial inhibition of cellular movement in Type I collagen.
Thus, the rotating-wall vessel culture system provides a model for analyzing the microgravity-induced inhibition of lymphocyte
locomotion and the investigation of the mechanisms related to lymphocyte movement. 相似文献
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植物形态性状叶面积简单易测, 能够反映植物对环境的适应与响应, 指示生态系统的功能与过程。在野外测定叶面积时, 叶片取样数量往往采用约定俗成的10-20片, 但到底采集多少叶片才是最优和最具代表性, 却少有探究。该研究以浙江金华山常绿落叶阔叶混交林的优势树种木荷(Schima superba)与枫香树(Liquidambar formosana)为研究对象, 通过对5个胸径等级植株和每个植株6个方位开展大批量叶片取样(>2 500个), 分析两个树种的叶面积变异特征, 探讨叶片取样数量为多少才能最代表该森林类型的叶片大小性状规律。结果表明, 常绿乔木木荷平均叶面积与变幅均小于落叶乔木枫香树。木荷叶面积与胸径无显著相关性, 而枫香树叶面积与胸径有较显著相关性, 但两个树种均在中胸径等级(15-20 cm)差异不显著; 两个树种的叶面积与采样方位无显著相关性, 但在东、西和底部的差异不显著。因此, 综合考虑代表性与野外可操作性, 叶片采集首选中胸径成树的底部叶片。随机抽样统计可知, 树木叶面积测定的最适叶片采集数量因物种而异, 木荷的最适叶片采集数量为40, 而枫香树最少为170片。因此, 在叶面积测定时, 叶片采集的数量应该不能只局限在10-20片, 在人力、物力和时间等条件允许的情况下, 应该尽可能多地测定较多叶片的叶面积。 相似文献
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为了考察过量表达苹果酸酶对于E.coli NZN111(ldhA::Kan pfl::Cam)厌氧发酵产丁二酸的影响, 将连接有苹果酸酶基因sfcA的表达载体pTrc99a-sfcA转化进NZN111中, 构建了重组NZN111(pTrc99a-sfcA)。0.5 mmol/L IPTG诱导8 h后, 测定的苹果酸酶比酶活为30.67 u/mg, 比受体菌提高了140倍。采用两阶段发酵模式, 结果表明: 过量表达的苹果酸酶在NZN111体内催化了从丙酮酸到苹果酸的逆向反应, 丁二酸是发酵过程中积累的主要有机酸, 且当加入0.7 mmol/L IPTG诱导, 初始葡萄糖糖浓度为18.5 g/L时, 选择对数生长期后期的菌种以10%的接种量转入厌氧发酵, 发酵结束时发酵液中丁二酸的浓度为12.84 g/L, 对葡萄糖的收率为69.43%, 乙酸为0.58 g/L, 二者浓度比为22:1, 没有检测到甲酸和乳酸。构建的菌种具有高产丁二酸和副产物极少的优点, 在同类菌种中处于先进水平。 相似文献