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1

Aerial photographs of mainland China acquired by U-2 spy planes: their characteristics and potential uses

Sato R., Kobayashi S., Jia R.

Teledetekcja Środowiska

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2016

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T. 54

61--73

EN

This paper reported characteristics of aerial photographs of mainland China taken by U-2 spy planes, which were archived and made public in NARA II of USA, and discussed the possibility to use them for environmental studies. U-2 photographs of China, which have high ground resolution of about 75cm were mainly taken in the first half of 1960s. Large amount of photographs including oblique photos as well as overlapped vertical photos covers vast range of China and enable us to use for detailed stereoscopic interpretation as well as creating ortho photos and digital surface models. Case studies in Loess Plateau (Shaanxi Province, China) showed the possibility of detailed observations of land features and land uses such as cave dwellings, check dams, agricultural terraces and cultivated crops, as well as estimation of the amount of gully erosion. In the process of archival research in NARA II, however, various inconveniences were found and improvement of retrieval system were desired.

PL

W artykule opisano charakterystykę zdjęć lotniczych Chin kontynentalnych wykonanych przez samoloty szpiegowskie U-2, które zostały zarchiwizowane i upublicznione w NARA II w USA, a także omówiono możliwości wykorzystania ich w studiach ochrony środowiska. Fotografie lotnicze z samolotów U-2, wykonanych nad terytorium Chin, mają wysoką rozdzielczość terenową, wynoszącą około 75 cm, zostały wykonane głównie w pierwszej połowie lat sześćdziesiątych XX wieku. Duża liczba zdjęć, w tym zdjęcia skośne, a także zdjęcia pionowe w pokryciu stereoskopowym obejmują znaczną powierzchnię Chin. Pozwalają one na szczegółową interpretację stereoskopową, jak również na tworzenie ortozdjęć i cyfrowych modeli terenu. Studia przypadków na płaskowyżu lessowym (prowincja Shaanxi, Chiny) wskazały na możliwość szczegółowych obserwacji cech terenu i użytkowania gruntów, takich jak mieszkania w jaskiniach, tamy kontrolne, tarasy rolnicze i pola uprawne, a także oszacowanie wielkości erozji. W procesie korzystania z archiwalnych zasobów zdjęć w NARA II (National Archives and Records Administration - USA) stwierdzono różne niedogodności i pożądane było ulepszenie systemu pobierania zdjęć.

2

Traffic and Tillage Effects on Soil Water Conservation and Winter Wheat Yield in the Loess Plateau, China

Chen H.

Ecological Chemistry and Engineering. S

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2013

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Vol. 20, nr 3

507--517

EN

In semi-humid Loess Plateau of northern China, water is the limiting factor for rain-fed crop yields. In this region, long-term traditional ploughing with straw removal has resulted in poor soil structure, water conservation and crop yield. Controlled traffic, combined with no-till and straw cover has been proposed to improve soil water conservation and crop yield. From 1999 to 2007, a field experiment on winter wheat was conducted in the dryland area of Loess Plateau of northern China, to investigate the effects of traffic and tillage on soil water conservation and crop yield. The field experiment was conducted using two controlled traffic treatments, no tillage with residue cover and no compaction (NTCN), shallow tillage with residue cover and no compaction (STCN) and one conventional tillage treatment (CK). Results showed that controlled traffic system reduced soil compaction in the top soil layer, increased soil water infiltration. The benefit on soil water infiltration translated into more soil conservation (16.1%) in 0-100 cm soil layer in fellow period, and achieved higher soil water availability at planting (16.5%), with less yearly variation. Consequently, controlled traffic system increased wheat yield by 12.6% and improved water use efficiency by 5.2%, both with less yearly variation, compared with conventional tillage. Within controlled traffic treatments, no tillage treatment NTCN showed better overall performance. In conclusion, controlled traffic combined with no-tillage and straw cover has higher performance on conserving water, improving yield and water use efficiency. It is a valuable system for soil and water conservation for the sustainable development of agriculture in dryland China.

PL

Na Wyżynie Lessowej w północnych Chinach woda deszczowa jest czynnikiem ograniczającym wydajność plonów zbóż. W tym regionie tradycyjna orka połączona z usuwaniem słomy spowodowała osłabienie struktury gleby oraz redukcję zasobów wody, co w rezultacie doprowadziło do zmniejszenia plonów. Kontrolowany ruch maszyn, w połączeniu z rezygnacją z orki i wykorzystaniem słomianej osłony powierzchni gleby, zostały zaproponowane w celu poprawy ochrony gleby i zwiększenia plonów. W latach 1999-2007 na suchych obszarach Wyżyny Lessowej przeprowadzono doświadczenia polowe z wykorzystaniem pszenicy ozimej, których celem było zbadanie wpływu ruchu i sposobu uprawy gleby na ochronę zasobów wodnych i plony uprawianych roślin. Doświadczenie polowe przeprowadzono na polach uprawnych z kontrolowanym ruchem, przygotowanych na dwa sposoby. Jedno z pól było niezaorane, jego powierzchnia nie była utwardzana, pozostawiono nienaruszone resztki pokrycia (NTCN). Drugie pole było podobnie przygotowane, ale w odróżnieniu od pierwszego zastosowano płytką orkę (STNC). Otrzymane wyniki porównano do tych, które uzyskano z pól przygotowanych w sposób konwencjonalny (CK). Wyniki wykazały, że kontrola i ograniczenie ruchu zmniejszyły zbijanie się górnych warstw gleby, zwiększając przenikanie wody w głąb niej. Korzystnym skutkiem przenikania wody do gleby była lepsza jej ochrona (16,1%) w warstwie 0-100 cm w kolejnych okresach i większa dostępność wody w glebie w czasie wysiewu (16,5%), przy mniejszej rocznej zmienności. W wyniku wykorzystania systemu sterowania ruchem plony pszenicy wzrosły o 12,6%, a efektywności wykorzystania wody poprawiła się o 5,2% w porównaniu z uprawą tradycyjną. Najlepszą ogólną wydajność zaobserwowano na polu NTCN. Podsumowując, można stwierdzić, że kontrola ruchu, brak orki i ochrona powierzchni za pomocą słomy mają znaczny wpływ na ochronę zasobów wody w glebie, poprawiając wydajność produkcji i efektywność wykorzystania wody. Opisany system ochrony gleby i wody jest istotny dla zrównoważonego rozwoju rolnictwa na suchych obszarach Chin.

3

Performance of soil particle-size distribution models for describing deposited soils adjacent to constructed dams in the China Loess Plateau

Zhao P., Shao M., Horton R.

Acta Geophysica

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2011

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Vol. 59, no. 1

124-138

EN

Soil particle-size distributions (PSD) have been used to estimate soil hydraulic properties. Various parametric PSD models have been proposed to describe the soil PSD from sparse experimental data. It is important to determine which PSD model best represents specific soils. Fourteen PSD models were examined in order to determine the best model for representing the deposited soils adjacent to dams in the China Loess Plateau; these were: Skaggs (S-1, S-2, and S-3), fractal (FR), Jaky (J), Lima and Silva (LS), Morgan (M), Gompertz (G), logarithm (L), exponential (E), log-exponential (LE), Weibull (W), van Genuchten type (VG) as well as Fredlund (F) models. Four-hundred and eighty samples were obtained from soils deposited in the Liudaogou catchment. The coefficient of determination (R2), the Akaike’s information criterion (AIC), and the modified AIC (mAIC) were used. Based upon R2 and AIC, the three- and four-parameter models were both good at describing the PSDs of deposited soils, and the LE, FR, and E models were the poorest. However, the mAIC in conjunction with R2 and AIC results indicated that the W model was optimum for describing PSD of the deposited soils for emphasizing the effect of parameter number. This analysis was also helpful for finding out which model is the best one. Our results are applicable to the China Loess Plateau.

4

Leaf stoichiometric trait and specific leaf area of dominant species in the secondary succession of the Loess Plateau

An H., Shangguan Z.

Polish Journal of Ecology

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2010

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Vol. 58, nr 1

103-113

EN

Ecological stoichiometry is the study of the balance of multiple chemical elements in ecological interactions. Terrestrial plants exhibit inter- and intra-specific differences in leaf C:N:P stoichiometry that has been used to study plant competition and succession, nutrient use efficiency, N and P nutrient limitation. However, little is known about leaf C:N ratio, N:P ratio in the Loess Plateau, particularly the pattern of leaf C:N:P stoichiometry during the secondary succession. Thus, leaf stoichiometric traits and specific leaf area (SLA) of dominant species at different secondary successional stages in the Loess Plateau were measured. The study was conducted at the Lianjiabian forest region of the Loess Plateau (35.03[degrees]-36.37[degrees]N and 108.10[degrees]-109.08[degrees]E), Gansu, China. Leaf C:N:P stoichiometry and specific leaf area of 18 dominant species (herb) community stage (Stipa bungeana Trin, Bothriochloa ischaemun (Linn.) Keng, Carex lanceolata Boott, Artemisia sacrorum Ledeb, Pulsatilla chinensis (Bunge) Regel, Potentilla chinensis Ser), shrub community stage (Sophora viciifolia Hance, Hippophae rhamnoides (Linn.), Ostryopsis davidiana Decne, Rubus palmatus Thunb, Rosa xanthina Lindl, Acer ginnala Maxim, Spiraea pubescens Turcz, Ziziphus jujuba var. spinosa), early forest community stage (Populus davidiana Dode, Betula platyphylla Suk, Platycladus orientalis (Linn.) Franco), climax forest community stage (Quercus liaotungensis Koidz)) at four secondary successional stages were determined in the Loess Plateau in early June of 2006. The herb and shrub community stage had higher SLA than that in the early forest community stage and climax forest community stage. The Leaf C, N, C:N ratio and N:P ratio at different secondary successional stages were significantly different (P <0.05), but the leaf P didn't differ. The N:P ratio of herb community stage were significant difference from those of the others stages (shrub community stage, early forest community stage and climax forest community stage), but there were not significant difference among the shrub community stage, early forest community stage and climax forest community stage. N:P ratio shifts of the species were consistent along the successional sere, although the N:P ratio of the different species at a successional stage varied considerably. On community level, the lowest N:P ratio (9.8) was found in herb community stage in the secondary succession, the N:P ratio increased to 12.9 in shrub community stage, declined to 12.4 in early forest community stage, and increased in climax forest community stage (e.g. 12.6 in the Quercus liaotungensis Koidz community). The results suggest that the vegetation productivity of the Loess Plateau was N-limited at each secondary successional stage.

5

Changes in species richness and community productivity during succession on the Loess Plateau (China)

Wang K., Shao R., Shangguan Z.

Polish Journal of Ecology

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2010

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Vol. 58, nr 3

501-510

EN

We investigated changes in species richness, community biomass, and productivity during secondary forest succession in Ziwuling area of the Loess Plateau of China. Species richness(number of taxa) increased as the succession proceeds, and peaked at the climax forest community, but the richness growth gradually slowed down as the succession advanced. Community biomass rapidly increased from the herbaceous stage to the shrub stage and declined slightly in the climax forest stage. The maximum community biomass occurred in the pioneer forest stage. Community productivity followed an unimodal curve in the succession, and the maximum productivity occurred in the shrub community at the middle succession stage, and the communities maintained a low and stable productivity at the later succession stages. The herb and shrub species together determined community diversity during succession, while the tree species contributed less to diversity in the communities. The herb and shrub layers had a relatively low biomass, but contributed almost half of the productivity of the forest communities. The relationships between species richness, community biomass and productivity were unimodal during succession, but only the relationship between species richness and community biomass was significant.