Estimating mineral content of indigenous browse species using laboratory spectroscopy and sentinel-2 imagery

Trees provide low-cost organic inputs, with the potential to improve livelihoods for rural communities. Understanding foliar nutrients of tree species is crucial for integration of trees into agroecosystems. The study explored nitrogen (N), phosphorus (P), potassium (K) and calcium (Ca) concentrations of nine browse species collected from the bushveld region of South Africa using wet analysis and laboratory spectroscopy in the region 400–2500 nm, along with partial least squares (PLS) regression. We further explore the relationship between canopy reflectance of Sentinel-2 image and foliar N, P, K & Ca. Laboratory spectroscopy was significant for N estimation, while satellite imagery also revealed useful information about the estimation of nitrogen at landscape level. Nitrogen was highly correlated with spectral reflectance (R² = 0.72, p < 0.05) for winter and (R² = 0.88, p < 0.05) for summer, whilst prediction of phosphorus potassium and calcium were considered not accurate enough to be of practical use. Modelling the relationship using Sentinel-2 data showed lower correlations for nitrogen (R² = 0.44, p < 0.05) and the other nutrients when compared to the dried samples. The findings indicate that there is potential to assess and monitor resource quality of indigenous trees using nitrogen as key indicator. This multi-level remote sensing approach has promise for providing rapid plant nutrient analyses at different scales.     

Seasonal and spatial variation of flagellate communities in a tropical river

Heterotrophic flagellates (HF) play an essential function in the microbial food loops as it is an agent of biochemical cycling of limiting nutrients and being a useful bio-indicator of environmental changes. However, in spite of its profound role in aquatic ecosystem studies regarding the evaluation of the spatial and seasonal patterns of the flagellate communities are lacking in Bangladeshi water, and therefore, study on community pattern of HF in a tropical river like Padma River could be a best example for other tropical rivers of the world. The present investigation was performed with the primary objectives to evaluate flagellate community structure, their spatial and seasonal distribution patterns, and the role of hydro-biological and physicochemical variables in determining their variability. The study was conducted at selected four study sites in Padma river, Bangladesh for a period of two distinct season (dry and wet season) in 2018. Standard procedures were followed in collecting, analyzing and interpreting of sampled data. The study revealed a total of 18 genera with different degrees of specificity to hydro-biological and physicochemical variables. It further establishes significant seasonal patterns, rather than spatial differences in the distribution of the flagellate communities. We found that the higher precipitation intensity during monsoon was the critical determinant in hydrological, biological, and physicochemical fluctuations which caused a significant decline in the value of the above variables. Likewise, total phytoplankton, zooplankton, and total heterotrophic bacterial abundance was also declined five-folds during the wet season. Similarly, total abundance of HF showed a significant decline in the community during the wet season. Genus wise relative abundance (RA%) of Euglena (23.81 %) was the highest during the dry season. In conclusion, this research and data analysis techniques propose unique insights on the flagellate links to environmental and hydro-biological regime in a tropical river with global implications.     

含铜,铅等杂物粗银的湿法提纯方法

基于银、铜、铅及其盐类的氧化—还原性、溶解度和络合特性的不同而互相分离,达到分离铜、铅杂质,提纯银的目的,提供了一种纯度较高、效果良好的新型提取方法。     

声波在松散沉积物上的反射

将海底沉积物的为一种松散的湿颗粒介质，并假设海水与沉积物的界面是平的，由位移，动量密度及压强在界面处在连续性，导出平面声波在其上的反射系数，建立反射系数与沉积物的具体参数的联系。所得结果可化为前人用唯象理论所获得的形式。将理论与实验比较的结果表明，两者的一致性是好的。     

山东半岛近岸大气降水中的铝

根据1991－1995年间在黄海西北部的千里岩和青岛的八关山采集的雨水样品，对山东半岛近岸大气降水中铝的含量及其分布持征和影响因素进行了研究，结果表明，该区大气降水中的铝主要来自降水对陆源大气溶胶的淋洗和冲刷，具有显著的时空分布特异性，冬春季高于夏秋季，沿岸城市地带则高于远离陆地的海区，人文活动，气象条件及降水pH值是影响该地区大气降水中铝量的主要因素，通量计算显示大气沉降是陆源的铝向西北黄海输送的重要途径。     

河南省两场初雪的Q矢量诊断分析

2003年11月8～9目河南省发生了近10年来唯一一次初雪即达暴雪的过程。利用Q矢量方法和常规观测资料，将2003年11月8～9目和2000年11月7～8目过程中的Q矢量和水汽条件进行对比分析，结果表明：Q矢量散度场、水汽通量散度和Q矢量湿锋生函数与河南省暴雪预报有较好的对应关系，对降雪预报有指示作用。     

On the wet removal of gaseous and particulate sulfur and nitrogen species from the atmosphere

The role of trace gases and aerosol particles in the control of sulfur and nitrogen levels in atmospheric precipitation is estimated on the basis of the enrichment factor in the precipitation of these elements relative to particulate matter in the air. By using air and precipitation chemistry data obtained at a Hungarian background air pollution station (K-puszta) it is found that the fraction of ammonium, nitrate and sulfate in precipitation, due to the removal of particulate matter is at least 59, 27 and 31%, respectively. The relationship between wet depositions and air concentrations of different species is determined statistically by applying daily data set. The regression equations obtained make the estimation of the sub-cloud scavenging ratios possible and they give some information on the magnitude of in-cloud scavenging processes. The results show that the in-cloud scavenging is a determining factor for precipitation sulfate, while it is relatively unimportant in the case of ammonium. The sub-cloud scavening of NO₂ and SO₂ is not too significant. However, for HNO₃, and NH₃ it is an effective process. The sub-cloud scavenging ratio of sulfur and nitrogen-containing particles varies around 0.25×10⁶.     

地基GPS反演大气水汽总量的初步试验

1998年5~6月的“海峡两岸及邻近地区暴雨试验”(HUAMEX) 期间, 同时进行了小规模的地基GPS长时间连续估测大气水汽总量的外场试验。试验中应用探空和地面降水资料与GPS反演结果进行了比较分析。地基GPS反演的大气水汽总量与探空得到的大气水汽总量, 两者随时间演变的趋势一致, 两者估算的水汽总量平均偏低6.5 mm, 两者偏差的均方差为4.3 mm。GPS反演的大气水汽总量随时间明显的呈周期性变化, 平均周期为7.2天。从GPS反演的大气水汽总量随时间演变图上可以清楚地看出水汽的积累与释放过程, 并与地面降水存在一定的对应关系, 地面降水大多发生在GPS反演的水汽总量处于相对高值且变化率较大的时候。     

Experts' Perspectives on the Integration of Indigenous Knowledge and Science in Wet Tropics Natural Resource Management

Aboriginal inhabitants of the Wet Tropics of Queensland advocate for greater inclusion of their Indigenous knowledge (IK) in natural resource management (NRM) to fulfil their customary obligations to country and to exert their Native Title rights. Despite a legal and institutional framework for inclusion of IK in NRM, IK has so far been applied only sporadically. We conducted an ethnographic case study to investigate perceptions on IK, science and how they affect integration of the two knowledge systems in the Wet Tropics. Our results show that IK and science are perceived as different concepts; that integration is limited by weak Indigenous internal and external governance; and that stronger Aboriginal governance and more focused engagement strategies are required to further the application of IK in local NRM. We conclude by arguing that NRM in the Wet Tropics needs to be reconceptualised to accommodate IK holistically, by considering its epistemology and the values and ethic that underpin it.     

Using kernel density estimation to explore habitat use by seabirds at a marine renewable wave energy test facility

If Scottish Government targets are met, the equivalent of 100% of Scotland's electricity demand will be generated from renewable sources by 2020. There are several possible risks posed to seabirds from marine renewable energy installations (MREIs) and many knowledge gaps still exist around the extent to which seabird habitats can overlap with MREIs. In this study, underlying seasonal and interannual variation in seabird distributions was investigated using kernel density estimation (KDE) to identify areas of core habitat use. This allowed the potential interactions between seabirds and a wave energy converter (WEC) to be assessed. The distributions of four seabird species were compared between seasons, years, and in the presence and absence of WECs. Although substantial interannual variation existed in baseline years prior to WEC deployment, the KDEs for all four species analysed were closer to the mooring points in the presence of a WEC in at least one season. The KDEs for all four species also increased in area in at least one season in the presence of a WEC. The KDEs of the northern fulmar and great skua overlapped the mooring points during spring in the presence of a device. The density of observations close to the mooring points increased for great skua, northern gannet, and northern fulmar during summer in the presence of a device. These results suggest that none of the four species analysed have shown avoidance or an extreme change in distribution as a result of the presence of a WEC. The continued monitoring of seabirds during WEC deployments is necessary to provide further data on how distributions may change in response to the presence of WECs.