Spatial Heterogeneity of the Long-Term Environmental Variations in a Large Agricultural Wetland in North China: Implications for Wetland Restoration

The long-term ecological success of compensatory freshwater wetland projects has come into question based on follow-up monitoring studies over the past few decades. Given that wetland restoration may require many years to decades to converge to desired outcomes, long-term monitoring of successional patterns may increase our ability to fully evaluate success of wetland mitigation projects or guide adaptive management when needed. In Portsmouth, New Hampshire a 4 ha wetland was constructed in an abandoned gravel quarry as off-site compensatory mitigation for impacts to a scrub-shrub swamp associated with property expansion. Building upon prior evaluations from 1992 and 2002, we conducted a floral survey in 2020 to compare results with prior surveys to document vegetation successional trends over time. In addition, we monitored the avian community throughout the growing season as a measure of habitat quality. The plant community mirrored documented successional trends of freshwater wetland restoration projects as native hydrophytes dominated species composition. Plant species composition stabilized as the rate of turnover, the measurement of succession, declined by nearly half after 17 years. Researchers should consider long-term monitoring of specific sites to better understand successional patterns of created wetlands as we documented long time frames required for the development of scrub-shrub swamps, red maple swamps, and sedge meadows. High species richness was attributed to beaver activity, topographic heterogeneity from Carex stricta tussocks, and the seed bank from the application of peat from the original wetland. Habitat heterogeneity of open water, herbaceous cover, and woody vegetation supports a diverse avian community including 11 wetland dependent species. Although the mitigation project has not created the full area of lost scrub-shrub swamp after 35 years, it has developed a structurally complex habitat and diverse avian community that effectively provides the functions and values of the impacted system.

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Stability and Surface Uniformity of Selected Thiol-Coated SERS Surfaces

Applied Spectroscopy ◽

10.1366/0003702971942042 ◽

1997 ◽

Vol 51 (9) ◽

pp. 1355-1359 ◽

Cited By ~ 26

Author(s):

Timothy O. Deschaines ◽

Keith T. Carron

Keyword(s):

Spatial Heterogeneity ◽

Sodium Dodecylsulfate ◽

Surface Wetting ◽

Thiol Compounds ◽

Analytical Technique ◽

Term Stability ◽

Long Term Stability ◽

Surface Enhanced Raman ◽

Coated Surfaces

The use of surface-enhanced Raman scattering (SERS) as an analytical technique continues to grow, but questions about its viability remain. This paper addresses the concern about the long-term stability of the surfaces used with the SERS technique. We have studied the long-term stability of Ag surfaces coated with three different thiol compounds. For this study, we have used 1-propanethiol, 1-do-decanethiol, and p-cresolthiol to coat the Ag surfaces. These surfaces showed long-term stabilities of over a month with minimal surface degradation. In order to mimic a realistic application of SERS, we stored the coated surfaces in a solution of water. Sodium dodecylsulfate (SDS) was added to maintain consistent surface wetting conditions so that reproducible results were obtainable on a day-to-day basis. Spatial heterogeneity of the surfaces and coating was analyzed with a fiber-optic Raman system. The spatial heterogeneity of the surfaces explains the day-to-day variations observed in the detection when the same portion of the surface used for analysis varies from day to day.

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Long-term trends and variations in haze-related weather conditions in north China during 1980–2018 based on emission-weighted stagnation intensity

Atmospheric Environment ◽

10.1016/j.atmosenv.2020.117830 ◽

2020 ◽

Vol 240 ◽

pp. 117830 ◽

Cited By ~ 1

Author(s):

Jin Feng ◽

Hong Liao ◽

Yanjie Li ◽

Ziyin Zhang ◽

Yingxiao Tang

Keyword(s):

North China ◽

Weather Conditions ◽

Long Term Trends

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Contrasting Impacts of Long-Term Application of Biofertilizers and Organic Manure on Grain Yield of Winter Wheat in North China Plain

Agronomy ◽

10.3390/agronomy9060312 ◽

2019 ◽

Vol 9 (6) ◽

pp. 312 ◽

Cited By ~ 2

Author(s):

Amara Cisse ◽

Adnan Arshad ◽

Xiaofen Wang ◽

Fanta Yattara ◽

Yuegao Hu

Keyword(s):

Grain Yield ◽

North China Plain ◽

North China ◽

Farm Yard Manure ◽

Grain Yields ◽

The North ◽

The North China Plain ◽

Pig Farm ◽

1000 Grain Weight

The effects of long-term incorporation of organic manure and biofertilizers have been investigated on winter wheat in the North China Plain (NCP). The five-year field experiment (2013–2018) has illustrated the responses of grain yield and yield components. Seven fertilization approaches, included pig farm-yard-manure and biofertilizers amendments combined with five NPK% drop levels of chemical fertilizer ratio + organic fertilizer + biofertilizer (0, C+O+B) 25%, CL4; 50%, CL3; 75%, CL1; and 100%, CL0), without fertilizer as control (CK), in NCP during the years 2013–2018. Results showed that the grain yields of CL1 and CL2 were equivalent to CL0 in all growing seasons except 2014/2015. The grain yields of CL4 were 29.9% to 46.6% lower than that of CL0 during 2014/2015, 2016/2017, and 2017/2018. The valuable spike-number, grain number per-spike, and 1000-grain weight showed significant variations among different growing periods. Regression analysis of grain yield and yield components indicated that number grains per-spike showed significant increase in seed yield formation. The 1000-grain weight was the major parameter that influenced yield of moderate and low yielding periods, respectively. The results revealed that application of 30 m3 ha−1 pig farm-yard-manure and 20 kg ha−1 biofertilizers has reduced at least 50% of the NPK fertilization without dropping grain yields in the North China Plain.

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Long-Term Effect of Manure and Mineral Fertilizer Application Rate on Maize Yield and Accumulated Nutrients Use Efficiencies in North China Plain

Agronomy ◽

10.3390/agronomy10091329 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1329

Author(s):

Fan Fan ◽

Hongyan Zhang ◽

Gabriela Alandia ◽

Laichao Luo ◽

Zhenling Cui ◽

...

Keyword(s):

North China Plain ◽

North China ◽

Smallholder Farmers ◽

Mineral Fertilizer ◽

Organic Manure ◽

Soil Conditions ◽

Available N ◽

Fertilizer Application Rate ◽

Maize Yields

Overuse of mineral fertilizer has become common at the North China Plain. Simultaneously, more organic manure resources are available for smallholder farmers. In order to increase the use of organic manure and reduce mineral fertilizer applications, a 10-year fertilization experiment with maize took place between 2008 and 2017. We assessed the long-term effects of cattle manure (CM) application and a complete nutrient substitution with mineral fertilizer (MF) at four application levels (3, 6, 9 and 12 t ha−1 CM) on yield, macronutrients (N, P and K) use efficiencies and soil conditions. Results showed that maize yields from CM and MF treatments differed across time and were significantly different in the first year of the experiment to no significant differences with increasing experimental time. In addition, increased MF levels did not result in increased maize yields; this response was different with CM applications. The highest 10-year maize average yield was 7.7 t ha−1 obtained with 9 t ha−1 of CM. Our results also showed that at the lowest application level (3 t ha−1 CM), the partial factor productivity (PFP) and the agronomic efficiency (AE) of all macronutrients were significantly higher with MF than with CM applications. Nevertheless, these differences narrowed with increased fertilizer input levels. The MF and CM recovery efficiency (RE) of N, P and K performed differently. Generally, MF exhibited significantly higher N-RE than CM treatments. CM treatments had significantly higher P-RE, but no K-RE differences were found between CM and MF. Soil available N, P and K significantly increased when fertilizer levels raised. MF treatments exhibited similar levels of soil available N, but lower soil available P and K compared with CM treatments.

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Assessing groundwater availability and the response of the groundwater system to intensive exploitation in the North China Plain by analysis of long-term isotopic tracer data

Hydrogeology Journal ◽

10.1007/s10040-018-1761-y ◽

2018 ◽

Vol 26 (5) ◽

pp. 1401-1415 ◽

Cited By ~ 6

Author(s):

Chen Su ◽

Zhongshuang Cheng ◽

Wen Wei ◽

Zongyu Chen

Keyword(s):

North China Plain ◽

North China ◽

Groundwater System ◽

Isotopic Tracer ◽

Groundwater Availability ◽

The North ◽

The North China Plain ◽

Intensive Exploitation

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Long‐Term Earthquake Hazard in North China Estimated from a Modern Catalog

Bulletin of the Seismological Society of America ◽

10.1785/0120190066 ◽

2019 ◽

Vol 109 (6) ◽

pp. 2340-2355 ◽

Cited By ~ 1

Author(s):

Ziyao Xiong ◽

Jiancang Zhuang ◽

Shiyong Zhou

Keyword(s):

Bayesian Method ◽

North China ◽

Voronoi Tessellation ◽

Earthquake Hazard ◽

B Value ◽

Estimation Methods ◽

Earthquake Catalog ◽

Function Estimation ◽

Simulation Experiments

Abstract In this study, to obtain optimal estimates of the earthquake hazard in North China based on the modern earthquake catalog, we used two variable kernel function estimation methods, proposed by Stock and Smith, and Zhuang, the Bayesian Delaunay tessellation smoothing method by Ogata (ODTB), and a newly proposed incomplete centroidal Voronoi tessellation (ICVT) method, to calculate the total and background seismic spatial occurrence rates for the study area. The sophisticated ODTB method is more stable than the others, but is relatively expensive, in terms of computation demands, whereas Zhuang et al.’s kernel estimate and the new ICVT method are able to provide reasonable estimates and easier to implement. We also calculated the spatial variations of the b‐value, using the Bayesian method with smoothness prior proposed by Ogata. Using comparative analyses and simulation experiments, we show that all of the methods give similar spatial patterns of seismic occurrences.

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