Atmospheric dry and wet nitrogen deposition on three contrasting land use types of an agricultural catchment in subtropical central China

2013 ◽  
Vol 67 ◽  
pp. 415-424 ◽  
Author(s):  
Jianlin Shen ◽  
Yong Li ◽  
Xuejun Liu ◽  
Xiaosheng Luo ◽  
Hong Tang ◽  
...  
Keyword(s):  
Land Use ◽  
Nitrogen Deposition ◽  
Central China ◽  
Land Use Types

Comparison of nitrogen deposition across different land use types in agro-pastoral catchments of western China and Mongolia

2019 ◽  
Vol 199 ◽  
pp. 313-322 ◽  
Author(s):  
Jinling Lv ◽  
Andreas Buerkert ◽  
Katherine B. Benedict ◽  
Guojun Liu ◽  
Chaoyan Lv ◽  
...  
Keyword(s):  
Land Use ◽  
Nitrogen Deposition ◽  
Western China ◽  
Land Use Types

scholarly journals Determination of Occurrences, Distribution, Health Impacts of Organochlorine Pesticides in Soils of Central China

2019 ◽  
Vol 16 (1) ◽  
pp. 146 ◽  
Author(s):  
Tekleweini Gereslassie ◽  
Ababo Workineh ◽  
Onyango Janet Atieno ◽  
Jun Wang
Keyword(s):  
Land Use ◽  
Organochlorine Pesticides ◽  
Solid Phase ◽  
Total Concentration ◽  
Soil Layer ◽  
Central China ◽  
Composition Analysis ◽  
Barren Land ◽  
Land Use Types ◽  
Subsurface Soil

Organochlorine pesticides are groups of chemicals applied to prevent pest and insect infestation. This study was aimed at investigating the concentration, potential sources, cancer risk and ecological toxicity of organochlorine pesticides (OCPs) in Huangpi district, Wuhan, China. Eight OCPs in soil samples collected from four land-use types at depths of 0–10 and 10–20 cm were examined. Sample extraction was carried out by solid phase matrix extraction method and analyzed using Agilent gas chromatograph 7890B equipped with electron capture detectors (ECD). The total concentration of OCPs ranged from 0.00–32.7 ng g−1 in the surface and 0.01–100.45 ng g−1 in the subsurface soil layer. Beta hexachlorocyclohexanes (β-HCH) with 2.20 and 7.71 ng g−1 in the surface and subsurface soil layers, respectively, was the dominant compound. The mean concentrations of OCPs in all samples were less than the threshold values for hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethane (DDTs) in China soil. Concentration of OCPs in the four land-use types were in the order of: paddy field > barren land > farmland > plastic greenhouse. Results of composition analysis revealed recent application of lindane as a major and historical use of new technical HCHs as a minor source of HCHs. On the other hand, application of new technical p,p’-DDT is the main source of DDTs in the study area. The estimated lifetime average daily dose, incremental lifetime cancer risks and hazard quotient values revealed that there is less likelihood of carcinogenic and noncarcinogenic health risks on the local residents.

scholarly journals Improving Parcel-Level Mapping of Smallholder Crops from VHSR Imagery: An Ensemble Machine-Learning-Based Framework

2021 ◽  
Vol 13 (11) ◽  
pp. 2146
Author(s):  
Peng Zhang ◽  
Shougeng Hu ◽  
Weidong Li ◽  
Chuanrong Zhang ◽  
Peikun Cheng
Keyword(s):  
Machine Learning ◽  
Land Use ◽  
Precision Agriculture ◽  
Agricultural Land ◽  
Spatial Information ◽  
Classification Performance ◽  
Central China ◽  
Ensemble Machine Learning ◽  
Land Use Types ◽  
Crop Mapping

Explicit spatial information about crop types on smallholder farms is important for the development of local precision agriculture. However, due to highly fragmented and heterogeneous cropland landscapes, fine-scale mapping of smallholder crops, based on low- and medium-resolution satellite images and relying on a single machine learning (ML) classifier, generally fails to achieve satisfactory performance. This paper develops an ensemble ML-based framework to improve the accuracy of parcel-level smallholder crop mapping from very high spatial resolution (VHSR) images. A typical smallholder agricultural area in central China covered by WorldView-2 images is selected to demonstrate our approach. This approach involves the task of distinguishing eight crop-level agricultural land use types. To this end, six widely used individual ML classifiers are evaluated. We further improved their performance by independently implementing bagging and stacking ensemble learning (EL) techniques. The results show that the bagging models improved the performance of unstable classifiers, but these improvements are limited. In contrast, the stacking models perform better, and the Stacking #2 model (overall accuracy = 83.91%, kappa = 0.812), which integrates the three best-performing individual classifiers, performs the best of all of the built models and improves the classwise accuracy of almost all of the land use types. Since classification performance can be significantly improved without adding costly data collection, stacking-ensemble mapping approaches are valuable for the spatial management of complex agricultural areas. We also demonstrate that using geometric and textural features extracted from VHSR images can improve the accuracy of parcel-level smallholder crop mapping. The proposed framework shows the great potential of combining EL technology with VHSR imagery for accurate mapping of smallholder crops, which could facilitate the development of parcel-level crop identification systems in countries dominated by smallholder agriculture.

LAND USE TYPES AND SOIL CHARACTERISTICTS: A CASE STUDY IN HUONG VINH COMMUNE, HUONG TRA TOWN, THUA THIEN HUE PROVINCE

2017 ◽  
Vol 126 (4B) ◽  
Author(s):  
Trần Thanh Đức
Keyword(s):  
Land Use ◽  
Sweet Potato ◽  
Soil Analysis ◽  
Soil Characteristics ◽  
Low Ph ◽  
Clay Loam ◽  
Total N ◽  
Land Use Types ◽  
Total P

This research carried out in Huong Vinh commune, Huong Tra town, Thua Thien Hue province aimed to identify types of land use and soil characteristics. Results showed that five crops are found in Huong Vinh commune including rice, peanut, sweet potato, cassava and vegetable. There are two major soil orders with four soil suborders classified by FAO in Huong Vinh commune including Fluvisols (Dystric Fluvisols<em>, </em>Gleyic Fluvisols and Cambic Fluvisols) and Arenosols (Haplic Arenosols). The results from soil analysis showed that three soil suborders including Dystric Fluvisols<em>, </em>Gleyic Fluvisols and Cambic Fluvisols belonging to Fluvisols were clay loam in texture, low pH, low in OC, total N, total P<sub>2</sub>O<sub>5</sub> and total K<sub>2</sub>O. Meanwhile, the Haplic Arenosols was loamy sand in texture, poor capacity to hold OC, total N, total P<sub>2</sub>O<sub>5</sub> and total K<sub>2</sub>O

THE IMPACT OF DIFFERENT URBAN LAND USE TYPES ON AIR POLLUTION IN THE MEGACITY OF SÃO PAULO

2020 ◽  
Vol 7 (1) ◽  
pp. 91
Author(s):  
Júlio Barboza Chiquetto ◽  
Maria Elisa Siqueira Silva ◽  
Rita Yuri Ynoue ◽  
Flávia Noronha Dutra Ribieiro ◽  
Débora Souza Alvim ◽  
...  
Keyword(s):  
Land Use ◽  
Air Pollution ◽  
Urban Land ◽  
Sao Paulo ◽  
Urban Land Use ◽  
São Paulo ◽  
Land Use Types ◽  
The Impact

A poluição do ar é influenciada por fatores naturais e antropogênicos. Quatro pontos de monitoramento (veicular, comercial, residencial e background urbano (BGU))da poluição do ar em São Paulo foram avaliados durante 16 anos, revelando diferenças significativas devidoao uso do solo em todas as escalas temporais. Na escala diurna, as concentrações de poluentes primários são duas vezes mais altas nos pontos veicular e residencial do que no ponto BGU, onde a concentração de ozonio (O3) é 50% mais alta. Na escala sazonal, as concentrações de monóxido de carbono(CO) variaram em 80% devido ao uso do solo, e 55% pela sazonalidade.As variações sazonais ede uso do solo exercem impactos similares nas concentrações de O3 e monóxido de nitrogênio (NO). Para o material particulado grosso (MP10) e o dióxido de nitrogênio(NO2), as variações sazonais são mais intensas do que as por uso do solo. Na série temporal de 16 anos, o ponto BGU apresentou correlações mais fortes e significativas entre a média mensal de ondas longas (ROL) e o O3 (0,48) e o MP10 (0,37), comparadas ao ponto veicular (0,33 e 0,22, respectivamente). Estes resultados confirmam que o uso do solo urbano tem um papel significativo na concentração de poluentes em todas as escalas de análise, embora a sua influência se torne menos pronunciada em escalas maiores, conforme a qualidade do ar transita de um sistema antropogênico para um sistema natural. Isto poderá auxiliar decisões sobre políticas públicas em megacidades envolvendo a modificação do uso do solo.

Anti-soil erodibility of different land use types in Northwest Guangxi Karst Regions

2012 ◽  
Vol 20 (1) ◽  
pp. 105-110 ◽  
Author(s):  
Jia CHEN ◽  
Hong-Song CHEN ◽  
Teng FENG ◽  
Ke-Lin WANG ◽  
Wei ZHANG
Keyword(s):  
Land Use ◽  
Soil Erodibility ◽  
Land Use Types
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