A major disturbance in nature, drought, has a significant impact on the vulnerability and resilience of semi-arid ecosystems by shifting phenology productivity. However, due to various mechanisms, primary productivity have remained largely ambiguous until now. This paper evaluated spatio-temporal changes based GIMMS NDVI3g time series data, demonstrated responses vegetation drought disturbances with standardized precipitation evapotranspiration index (SPEI) northern China. The results showed...

Alpine meadow and alpine steppe are the two most widely distributed nonzonal vegetation types in Qinghai-Tibet Plateau. In context of global climate change, differences spatial-temporal variation trends their responses to change discussed. It is great significance reveal response Plateau construction ecological security barriers. This study takes meadow, overall as research objects. The normalized difference index (NDVI) data meteorological were used sources between 2000 2018. By using mean...

Since the 1970s, a long-term research project has been conducted to monitor changes in primary productivity of Chinese fir plantation at Huitong Ecosystem Research Station, Hunan, China. Standing biomass and net (NPP) were investigated four times (7, 11, 14 18 years old) two successive rotations on same site. The mean individual tree stand second rotation reduced by ∼18, 17, 7 3 per cent 7-, 11-, 14- 18-year-old stands, respectively, compared with first rotation. In rotation, annual NPP was...

Accurate detection of vegetation cover and biomass shrub communities in sandy area is beneficial for evaluating ecosystem, improving remote sensing models, assessing the accuracy sensing. Unmanned aerial vehicles (UAVs) have replaced traditional measurement methods fraction coverage (FVC) owing to high spatial resolution their imagery, positioning accuracy, ease use. The existing detecting via UAVs, however, are not suitable surface fluctuations, dwarf shrubs, herbs. Futhermore, method...

Mu Us Sandy Land is a typical semi-arid vulnerable ecological zone, characterized by vegetation degradation and severe desertification. Effectively identifying desertification changes has been topical environmental issue in China. However, most previous studies have used single method or remote sensing index to monitor desertification, lacked an efficient high-precision monitoring system. In this study, optimal scheme that considers multiple indicators combination different machine learning...

As is a land degradation process caused by an uncoordinated Human-Earth relationship, aeolian desertification has threatened the safety of eco-environmental and development social economy in northern China. Although most studies focus on causes or driving forces with climatic anthropogenic factors, lack impact analysis relationship between climate change human activities, mechanism still remain unclear. In present study, first spatial patterns from 1975 to 2015 were obtained visual...

ABSTRACT Desertification seriously threatens the ecosystem security of Qinghai‐Tibetan Plateau and sustainable development human society. The regional warming humidification climate caused by global have brought uncertainty to desertification trend Plateau. Therefore, it is crucial pay close attention status trends desertification. In this study, Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation indexes, albedo topsoil grain size index (TGSI) data for were collected Google...

Abstract Changes in vegetation productivity and species composition have been used as conventional indicators of land degradation rehabilitation assessments. The two biophysical parameters vary nonlinearly during change process with various time lags, which provide, a whole, useful framework to diagnose degree rehabilitation. In this study, the net primary (NPP) water use efficiency (WUE), are proxies eco‐physiological properties related composition, were combined develop an assess...

Biological soil crusts (BSCs) play an essential role in desert ecosystems. Knowledge of the distribution and disappearance BSCs is vital for management ecosystems desertification researches. However, major remote sensing approaches used to extract are multispectral indices, which lack accuracy, hyperspectral have lower data availability require a higher computational effort. This study employs random forest (RF) models optimize extraction using band combinations similar two BSC indices...

Non–photosynthetic vegetation (NPV) plays a crucial role in arid and semi-arid ecosystems. Remote sensing methods can extract NPV information accurately quantitatively, which helps studying the water use, community health, climate response of communities. This study used backpropagation network (BP) random forest (RF) to test cover extraction from Landsat 8-OLI images Mu Us Sandy Land. Pixel-level cover, photosynthetic (PV) bare soil (BS) unmanned aerial vehicle (UAV) field sampling data...

Determining the responses of non-photosynthetic vegetation (NPV) and photosynthetic (PV) communities to climate change is crucial in illustrating sensitivity sustainability these ecosystems. In this study, we evaluated accuracy inverting NPV PV using Landsat imagery with random forest (RF), backpropagation neural network (BPNN), fully connected (FCNN) models. Additionally, inverted MODIS time-series data spectral unmixing. Based on this, analyzed precipitation drought across different...

For regional desertification control and sustainable development, it is critical to quickly accurately understand the distribution pattern spatial temporal changes of deserts. In this work, five different machine learning algorithms are used classify desert types on Qinghai–Tibetan Plateau (QTP), their classification performance evaluated basis results accuracy. Then, best model, Shapely Additive Explanations (SHAP) method clarify contribution each feature identification during process, both...

Biological soil crusts (BSCs) are a major functional vegetation unit, covering extensive parts of drylands worldwide. Therefore, several multispectral indices have been proposed to map the spatial distribution and coverage BSCs. BSCs composed poikilohydric organisms, activity which is sensitive water availability. However, studies on dry wet seldom considered mixed gradient that representative actual field conditions. In this study, in situ spectral data photographs 136 pairs plots were...

The purpose of this study is to reveal the seasonal difference in vegetation variation and its response climate factors Qilian Mountains (QM) under background global warming. Based on MOD13 A2 normalized index (NDVI) data meteorological data, analyzed spatiotemporal dynamics stability different seasons by using mean value method, trend analysis discussed their responses climatic based correlation method. results show that cover QM experienced a significant upward past 21 years, but there...

The purpose of this study was to select a burner by assessing the flame temperature distribution several typesof burners, build weeder, and quantitatively evaluate its effects on weed control. Barnyardgrass (54.4%) largecrabgrass (34.9%) were two dominant weeds in test field. significant variables tested gas pressure operatingspeed, which eventually led dose, i.e., amount LPG per unit area (kg/ha) needed for weedcontrol rate above 80% with dosage at 40 kg/ha or more, 90% over 60 kg/ha....