Desertification Control Research Articles

Ecological stoichiometry and homeostasis characteristics of plant-litter-soil system with vegetation restoration of the karst desertification control.

It is of great significance to clarify the ecologically chemical stoichiometric characteristics of plant-litter-soil in vegetation restoration process for elucidating the nutrient cycling law and soil nutrient management of karst ecosystem. The carbon (C), nitrogen (N) and phosphorus (P) contents of leaves, litter and soil and their stoichiometry were determined in loquat (Eribotrya japonica) plantations in a karst plateau canyon after 3, 6, 10 and 15 years of restoration. The homeostasis characteristics of leaf N, P, and N:P with the change in soil nutrients during restoration were revealed. The results showed that leaf C, N, and P contents initially increased and then decreased with increasing years of restoration at the same sampling time. The contents of nutrients in soil and litter varied with increasing restoration years, with the highest values mostly appearing in May and July. This could be due to greater moisture in May and July, which helps with nutrient absorption and transformation. The leaf N:P ratio of loquat with different restoration years was 35.76-47.39, with an average of 40.06. Therefore, loquat leaves may experience P limitation in the growth process. The relationships between N, P and N:P in leaves and soil indexes could be simulated by a homeostasis model. Except for the weak sensitivity of loquat leaf N in 10 years, the other indexes and treatments had a certain homeostasis. Plants maintain homeostasis by regulating physiological responses in vivo in response to soil nutrient changes, indicating that loquat has good adaptability in karst desertification environments, but attention should focus on the management of soil P in the field as part of the vegetation restoration process. Therefore, in future research, we should combine the soil water and fertilizer conditions of different growing seasons in karst rocky desertification areas and provide scientific field management to ensure that the results of rocky desertification management can play a role in rural revitalization.

Driven by utility or regret? Investigating the influence of decision-rule heterogeneity on public preferences for desertification control policies

In the matter of investigating public preferences and stated value for desertification control policies, the choice experiment (CE) could provide valuable insights. However, traditional CE studies modeled the data based on the random utility maximization (RUM) framework, which ignores the significant impact of decision rules on individual choice behavior, such as the random regret minimization (RRM). To examine the influence of decision-rule heterogeneity on public preferences for desertification control scenarios, this study introduced a generalized random regret minimization (G-RRM) model to analyze public choices and developed a hybrid latent class model incorporating the RUM, RRM, and G-RRM choice paradigms to clarify the formation mechanism of decision-rule heterogeneity. The findings indicate that all RRM models demonstrate a better fit with the data than the RUM model, and 68.77% of respondents express significant preference for the RRM choice paradigm. Regret can serve as an important driving factor in public choices for desertification control policies. The hybrid latent class model containing the G-RRM class with different attribute-specific values achieves the best fit, revealing that decision-rule heterogeneity significantly influences individuals' choice behavior, and such heterogeneity is not only among different respondents, but also in their trade-offs across various attributes. The results also reveal the relationship between respondents’ heterogeneous preferences for choice paradigms and their personality traits. Specifically, respondents with less education, residence years, and perceived usefulness of desertification control tend to prefer the RUM choice paradigm; female and respondents with more income, attention, and perceived usefulness of desertification control tend to prefer the RRM choice paradigm; as well as respondents with higher satisfaction to the current desertification situation show a greater decision-rule heterogeneity across different attributes. These results may provide interesting policy consequences, as they offer a precise comprehension of public choices for desertification control policies, through a combination of diverse decision rules.

Assessing the influences of natural and human factors upon desertification vulnerability in northern China during 1985–2010

As desertification is a major ecological and environmental problem affecting global sustainable development, it is imperative to assess the vulnerability of desertified land systems in order to formulate desertification control policies and improve livelihoods in arid lands. Using the vulnerability scoping diagram (VSD) and Geodetector method, we explored trends in desertification vulnerability by considering the exposure, sensitivity, and adaptability of the sandy region of northern China from 1985 to 2010, and identified the influencing mechanisms in terms of natural and human factors. According to the results, desertification vulnerability was higher in the central and western regions and lower in the eastern regions, and decreased significantly in most areas from 1985 to 2010. This could mainly be attributed to their reduced sensitivity, while the contributions of exposure and adaptability were relatively small in comparison to sensitivity. The spatial and temporal variations in the Normalized Difference Vegetation Index (NDVI) were the primary drivers of significant changes in desertification vulnerability in most areas, while the Net Primary Productivity (NPP), percentage of unused land, and grazing density were deemed secondary principal factors. Interactions between factors can reinforce the explanatory power of individual factors for changes in vulnerability, especially for wind erosion and GDP. The findings of this study could inspire governors to implement integrated measures to mitigate vulnerability and control desertification, including the restoration of vegetation on degraded land and enhancing the adaptability of the sandy region from both economical and ecological perspectives.

Research Progress on Grassland Eco-Assets and Eco-Products and Its Implications for the Enhancement of Ecosystem Service Function of Karst Desertification Control

Grasslands in karst ecological fragile areas can effectively mitigate climate change, conserve biodiversity, maintain human well-being, and play a significant role in improving the health of regional ecosystems and farmers’ livelihoods. Thus, the study of grassland ecological assets and ecological products comprehensively examines their effects on grassland ecosystem services based on the traditional paradigm. This procedure is crucial from a strategic perspective for rebuilding damaged grassland ecosystems in karst regions, strengthening the efficacy of desertification control, and encouraging sustainable economic growth. In this review, 143 pertinent works on grassland ecological assets and ecological products are numerically and qualitatively analyzed. The findings demonstrated the following: (i) After 2012, there was an exponential increase in the number of studies. The most frequently researched topics were ecological assets, functional enhancement, and service management contents, accounting for 82.09% of the total literature; the research regions were primarily distributed in Asia and North America. (ii) The research patterns were slowly diversifying and becoming more interdisciplinary. (iii) There are five key scientific issues to be addressed in the research on grassland ecosystems and we summarize the main developments and landmark achievements. (iv) There is an intrinsic relationship between grassland ecological assets, ecological products, and desertification control, and we propose insights into the enhancement of karst grassland ecosystem service functions based on three perspectives: fragile environment, trade-off synergy, and service management. This study provides valuable insights for the development of regional ecological livestock and the scientific promotion of integrated desertification control.

Multiscale and multifunctional analysis of the coupling relationship between land use and desertification

AbstractUnderstanding the interactions between land use and desertification in arid regions is crucial for both improving human well‐being and achieving the United Nations Sustainable Development Goals. However, there has been limited research on the effect of spatial scale on this relationship, especially within different land utilization function orientations. We used a revised coupling relationship index to analyze the complex interactions and dynamic changes between land use and desertification with multiscale and multifunctional oriented regions in the Tarim Basin, northwest China. Our results showed that the coupling relationship was more significant in small watersheds than in large watersheds. An inverted U‐shaped curve was observed for the coupling relationship with an increase in the proportion of cultivated land, which changed with the land utilization function orientations. The watersheds with a high proportion of unused land and a fragile ecological environment were dominated by negative coupling. Watersheds with roughly equal proportions of forest–grassland and cultivated land showed positive coupling and followed an inverted U‐shaped trend. Watersheds with a relatively high proportion of cultivated land may achieve a win–win situation with both the reclamation of cultivated land and the control of desertification. Our study proves the necessity of research about the coupling differences in different functional oriented regions and may also help to suggest action priorities to desertification control and ecological restoration.

Response of leaf blade in Zanthoxylum planispinum var. dintanensis to differences altitudes through integrated metabolomics and transcriptomics analysis

To analyze the effects of altitude on Z. planispinum var. Dintanensisin, leaves of samples from different altitudes (H1:1054 m.a.s.l., H2:821 m.a.s.l., H3:645 m.a.s.l.) were collected for integrative analysis of the metabolome and transcriptome in the present study. According to transcriptome data, a total of 9,566 differentially expressed genes (DEGs) were identified from the three sample comparisons (H1 vs. H2, H1 vs. H3, H2 vs. H3). Fewer DEGs were observed in the H2 vs. H3 group than in the other two comparison groups, suggesting that differences in the transcriptome increased with elevation. Most genes were involved in “Biosynthesis of secondary metabolites”, “Plant hormone signal transduction” and “MAPK signaling pathway-plant” based on KEGG enrichment analysis. In total, 423 differential metabolites (DAMs) were determined in the three comparisons (mentioned above) by using metabolomics analysis, of which flavonoids (14.91%) were dominant. Interestingly, more accumulation of terpenoids, aldehydes and esters was observed at higher altitudinal levels, while higher percentages of flavonoids and polyphenols were obtained at lower altitudes based upon K-Means analysis. A unique pathway (p value<0.01) linked to “flavonoid biosynthesis” appeared to have consistent expression patterns in the comparison of H1 vs. H3 based on network analyses of DEGs and DAMs. Notably, regarding the direct products of catalytic reactions, naringenin chalcone, aromadendrin, and naringenin were positively regulated by genes encoding CHS, F3H and CHI, respectively. In addition, the transcription levels of nine candidate genes, including CHI, CHS, CCoAOMT, 2ODDs, ANS, ANR, F3H, DFR and HCT, were confirmed by RT‒qPCR, which were consistent with transcriptional profile data regarding RNA-seq and further demonstrated that these genes involved in flavonoid biosynthesis contribute to the environmental adaptation of the blade in Z. planispinum var. Dintanensis. In summary, our findings represent the first integration of transcriptome data with widely targeted metabolomic data from Z. planispinum var. Dintanensis grown in rocky desertification control areas, which provides novel insights into adaptation to environmental stress. This study has the potential to improve the cultivation and management of Z. planispinum var. Dintanensis through various technologies to gain maximum medicinal production in the future.

Review of Desert Mobility Assessment and Desertification Monitoring Based on Remote Sensing

Desertification seriously hinders economic development and ecological security, which has led to increased research on desertification monitoring and control. Remote sensing technology is widely used in desert research due to its large detection range and ability to obtain target feature information without touching objects. In order to better monitor and control desertification, the research methods on desert mobility and dune morphology in mobile deserts were reviewed. Among them, an important index to distinguish mobile and nonmobile deserts is desert vegetation coverage. The research progress of desert vegetation coverage based on visual interpretation, the nonlinear spectral model, normalized vegetation index (NDVI) fitting and plant community classification was reviewed. The loss of vegetation in the transitional zone of the desert is a contributing factor to desertification. The new technologies and applications of desert area monitoring, the remote sensing ecological index, and desert feature information extraction were introduced and analyzed. To combat desertification more accurately and effectively, the classification methods of moving dunes based on deep learning were also reviewed. It can be concluded that desertification monitoring methods are gradually becoming more accurate and adaptive, but they remain insufficient and less mature. Therefore, exploring how to apply desertification control technology more scientifically and rationally is an extremely valuable area for research.

Effects of fine substance content in soil substrate on the formation of artificial cyanobacteria crusts.

The use of artificial cyanobacteria crusts is one of the effective methods to prevention and control of desertification. Soil fine substance is one of the important factors limiting the colonization and growth of artificial cyanobacteria crusts. We compared the growth of artificial cyanobacterial crusts with different fine substance contents by setting the volume ratios of fine substance to quicksand as 0:1, 1:1, 2:1, 4:1 and 1:0. The results showed that the cover of artificial cyanobacteria crusts increased gradually with the increases of fine substance contents, while the contents of chlorophyll a and extracellular polysaccharide firstly increased and then decreased slightly. The optimum growth of artificial cyanobacterial crusts was achieved under the treatment of 4:1 ratio. Under such treatment after 60 days of incubation, artificial cyanobacteria crusts cover was 70%, and the contents of chlorophyll a, loosely bound exopolysaccharide (LB-EPS), tightly bound exopolysaccharide (TB-EPS), and glycocalyx exopolysaccharide (G-EPS) were 17.5, 70.0, 175.0, and 200.0 μg·cm-2, respectively. Increasing the amount of cyanobacteria under the condition of low fine substance content could promote the formation and growth of artificial cyanobacterial crusts (0.5 g of cyanobacteria per petri dish was the optimal). It could provide a new idea for the large-scale culture of artificial cyanobacterial crusts inoculum.

Vegetation restoration in South China’s karst region under geological background constraint: Forest or non-forest

Over the past two decades, the karst region in southern China has emerged as a critical area for ecological conservation and restoration, attracting global attention for its efforts in ‘greening.’ However, particular areas face challenges transitioning into forests due to the carbonate bedrock constraint, which likely undermines sustainability of greening efforts in karst regions. This study overviews the significant achievements in vegetation restoration in the karst region of southwest China, emphasizing the potential of short-term ecological restoration in effectively sequestering carbon, a valuable approach to achieving carbon neutrality in the region. However, combating rocky desertification remains difficult due to geological limitations that hinder large-scale afforestation. Additionally, variations in soil and rock composition impact the success and quality of vegetation restoration, leading to some areas failing to establish forests. Therefore, establishing the goals for rocky desertification control in different regions (enhancement, degradation, or reduction) should be based on current conditions and the evolutionary characteristics of rocky desertification. To facilitate precise afforestation and grass planting in the karst region, factors such as climate, rock conditions, and human-environment relationships should be considered in regional divisions, including natural restoration zones, artificial afforestation zones, grass planting zones, and protected zones.

Intercropping Peanut under Forests Can Reduce Soil N2O Emissions in Karst Desertification Control

In the process of vegetation restoration for karst desertification management, the lack of scientific and rational intercropping technology and the blind application of large amounts of nitrogen fertilizer have made the soil the main source of atmospheric N2O in this region. How soil N2O emissions vary under different intercropping modes is a scientific question worthy of study. This study took a three-year-old loquat (Eribotrya japonica L.) artificial forest in the karst plateau canyon as the experimental site and designed loquat intercropping with peanut, corn, and sweet potato (Ipomoeabatatas (L.) Lam.) as well as non-intercropping to analyze the differences in soil physicochemical properties and greenhouse gas emissions under different intercropping patterns. The results showed that intercropping with peanut significantly increased loquat yield, soil moisture, temperature, SOC, MBC, TN, and MBN content. The emissions of N2O and CO2were mainly positively correlated with soil moisture and temperature, while CH4 showed a negative correlation with soil moisture and soil temperature. The soil absorbed CH4 in the control of karst desertification. Karst area soils exhibited higher N2O emissions. Intercropping patterns significantly influenced soil N2O emissions, with N2O-N cumulative emissions ranging from 5.28 to 8.13 kg·hm−2 under different intercropping conditions. The lowest N2O-N cumulative emissions were observed for peanut intercropped under the forest. The peak N2O emission occurred in April 2022, which may be attributed to the higher rainfall and soil moisture during that month. Intercropping peanut with loquat significantly reduced the global warming potential. Therefore, intercropping peanut in young forests can improve soil water and fertilizer conditions, reduce soil N2O emissions and global warming potential, and serve as a nitrogen fixation and emission reduction technique suitable for karst desertification areas.

Ecological Stoichiometric Characteristics of Plant–Soil–Microorganism of Grassland Ecosystems under Different Restoration Modes in the Karst Desertification Area

C, N and P are the key biogenic elements of terrestrial ecosystems, and their biogeochemical processes regulate nutrient cycling and play a key role in restoring degraded ecosystems. In this paper, the grassland ecosystem under artificial restoration measures (Dactylis glomerata (DG), Lolium perenne (LP), Lolium perenne + Trifolium repens (LT)), and the natural restoration measures (NG) in a typical karst plateau desertification control area of southwest China, were taken as the research object. The C, N, and P concentrations and the ecological stoichiometry of the plant–soil–microorganism system in grasslands under different restoration measures in the karst desertification area were explored. We established the following findings: (1) Compared with NG, the C, N and P concentrations of plants and soil in DG, LP and LT were higher, and LT was the highest. (2) The microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) and microbial biomass phosphorus (MBP) concentrations in LT was also the highest. (3) The C:N ratio of plant and soil indicated that the N mineralization and nutrient release rate of DG, LP and LT were stronger than that of NG, and the plant growth of NG was most seriously limited by nitrogen. The N:P ratio in plant and soil indicated that the grassland was limited by P in the four treatments. (4) The result of correlation analysis showed that the cycling process of C, N and P in the plant–soil–microorganism system was coupled, and that the elements closely affected each other. In general, the effect of artificial restoration on a degraded ecosystem was relatively better than the natural restoration for increasing plant, soil and microbial nutrient concentrations, especially in the mixed-seed ecosystem of leguminous and gramineous forage. However, in the future, grassland management, appropriate N fertilizer or N-fixing plants and P fertilizer should be considered to improve the limitation of plant N and P, so as to realize the sustainable development of grasslands and the restoration of degraded ecosystems in the karst desertification control area.

The impact of multiple driving factors on forest ecosystem services in karst desertification control

In the fragile karst desertification ecosystem, forests are the providers of eco-multifunctionality. And the ecosystem service (ES) supply capacity of forests is directly or indirectly affected by various driving factors. The aim of this study is to explore the driving role of forest spatial structure, species diversity, and functional diversity on ecosystem services. In this study, four forest types, namely, broad-leaved monoculture forest (planted economic forest) (F1), broad-leaved mixed forest (F2), coniferous and broad-leaved mixed forest (F3), and coniferous mixed forest (F4), were investigated in karst plateau mountain (KPM), karst plateau canyon (KPC), and karst mountain canyon (KMC) landforms. Variance analysis, correlation analysis and redundancy analysis were used to compare the differences of spatial structure, species diversity, functional diversity, and ES of different forest types and to clarify the driving role of spatial structure, species diversity, and functional diversity on ES. The results showed that the wood supply service of F3 was at least 4.27% higher than that of other forest types; carbon sequestration and oxygen release are at least 4.57 and 3.89% higher; the water holding capacity of litter and soil is higher by 6.24 and 2.26%, respectively; the soil OC, TN, TP, and TK were higher than 6.01, 1.22, 25.55, and 13.34%, respectively. The coniferous mixed forest and broadleaved mixed forest with a more complete spatial structure has a higher level of diversity, which can generate more wood and provide more soil nutrient sources, as well as stronger regulation capacity. Spatial structure affects plant productivity through interspecific relationships; soil fertility is restricted by the level of diversity; gas and water regulation are influenced by both spatial structure and diversity levels. There is a progressive driving relationship among spatial structure, diversity, and ES. In forest management, it is helpful to improve the forest ecosystem’s functioning by adjusting the forest structure using close-to-natural management measures.

Spatial pattern of hydrological and erosion behaviour along a dolomite hillslope in Southwest China

Dolomite hillslopes are highly vulnerable to rocky desertification, but the linkages among soil type, runoff mechanisms, and soil erosion remain unclear. During four hydrological years (2018–2021), soil type, plot-scale hydrological and erosion behavior at the upper, middle, and lower slopes along the dolomite hillslope in karst regions of Southwest China were investigated. The results indicated that along the downward slope direction, the degree of soil development gradually increased, forming a typical soil catena pattern. The soil types along the downward direction on the dolomite hillslope gradually transitioned from Entisol to Inceptisol and to Semi-Alfisol. The Entisol was thin and gravelly, with the highest volume ratio of gravel of 75 %. In contrast, Semi-Alfisol was thick and clayey, with the highest volume ratio of fine soil of 97 %. The surface runoff coefficient of the upper slope was only 2.3 % because of the high water infiltration capacity of shallow and rocky soil, and the runoff generation mode was dominated by discontinuous infiltration–excess runoff occurring on rock outcrop patches. Due to the higher soil water content (mean value of 37 %) and frequently occurring lateral flow, the lower slope exhibited the highest surface runoff coefficient of 21 %, mainly as saturation-excess runoff. Catenary soils and their correspondingly divergent hydrological regimes led to average annual soil losses of 0.4, 0.8, and 2.8 t·ha−1·yr−1 at the upper, middle, and lower slopes, respectively. These results advance the understanding of the relationship between hydrology and erosion on karst hillslopes and provide theoretical support for further rocky desertification control.

Effects of Heavy Metals on Nitrogen in Soils of Different Ecosystems in the Karst Desertification of South China

Nitrogen, as a crucial limiting nutrient in terrestrial ecosystems, plays a vital role in determining land quality. Heavy metals, as drivers of soil substance transformation, are important indicators for assessing ecosystem function. Currently, the relationship between soil nitrogen and heavy metals in karst desertification areas remains unclear. Therefore, this study focuses on the soil of grassland, forest, and agroforestry ecosystems in a karst desertification area to investigate the relationship between heavy metals and nitrogen distribution using ecological stoichiometry. The findings revealed the following: (i) Total nitrogen (TN) and available nitrogen (AN) exhibited the trend of agroforestry * &gt; forest &gt; grassland, while soil microbial biomass nitrogen (SMBN) showed the trend of forest * &gt; grassland * &gt;&gt; agroforestry; (ii) Chromium (Cr), Ferrum (Fe), Niccolum (Ni), and Plumbum (Pb) showed the trend of agroforestry * &gt; grassland &gt; forest, while Cuprum (Cu) demonstrated the trend of agroforestry &gt; grassland &gt; forest, and Zincum (Zn) exhibited the trend of grassland &gt; forest * &gt;&gt; agroforestry. The Nemerow comprehensive pollution index were 0.77 for grassland, 0.69 for forest, and 0.94 for agroforestry; (iii) The sensitivity of soil nitrogen and heavy metals ranked as grassland &gt; agroforestry &gt; forest. The research findings aim to provide a scientific reference for karst desertification control, ecological protection and restoration, and enhancement of ecosystem function.

Evaluating land restoration based on the land cover in the Horqin Sandy Land, China.

Land degradation is a severe ecological environmental issue in arid and semiarid areas. Evaluating land degradation exactly is essential for maintaining the security of the ecological environment. This study evaluated land restoration in terms of land cover changes in the Horqin Sandy Land from 2000 to 2018 and analyzed the related influencing factors. The results showed that land restoration and land degradation accounted for 37.55% and 4.47% of the total area, respectively. Land restoration has improved substantially, and desertification control has achieved remarkable effects. NPP trends should be analyzed in combination with land cover types. When the land cover has changed, the type of land cover change and the period need to be clarified before analyzing the corresponding NPP trend to depict the land productivity accurately. The vegetation NPP changes following land cover conversions were more essential than land cover change types. Changes in precipitation and temperature had positive effects on the growth of vegetation and land restoration. In general, human activities promoted land restoration, including grazing policies, cropland utilization activities, and ecological restoration projects. Current land restoration, however, essentially sacrifices the groundwater resources, which challenges the sustainability of land restoration. Appropriate land use strategies were proposed to promote sustainable land use, including preventing vegetation degradation following land cover conversions, improving grassland construction, and coordinating the usage of cropland and water resources. Such results are meaningful for promoting land restoration and realizing sustainable land development.

Using Ecological Stoichimetric Characteristies to Inform Grassland Management in the Karst Desertification Area

C, N and P play an important indicator role in explaining the material cycles and elemental balances of living and non-living systems. In order to control karst rocky desertification, China has established a large number of artificial grasslands for the development of herbivorous animal husbandry, which has played an important role in ecological restoration and economic development. However, the effects of different use patterns on the ecological stoichiometry of the carbon (C), nitrogen (N) and phosphorus (P) of the grassland plant–soil–microorganism are not clear. In this study, the effects of grazing grassland (GG), mowing grassland (MG) and enclosed grassland (EG) on C, N and P and their ecological stoichiometry in the artificial grassland plant–soil–microbe were investigated in the karst desertification control area in Southern China. The results showed that (1) the C content was EG &gt; GG &gt; MG. The N content was GG &gt; EG &gt; MG, while the P content was MG &gt; GG &gt; EG. C:N, C:P and N:P were shown as EG &gt; GG &gt; MG. The plant N:P was more than 20, indicating a P deficiency and limitation, especially in EG. (2) The content of C and P in soil was EG &gt; GG &gt; MG. The N content was GG &gt; EG &gt; MG. The soil C:N showed EG &gt; MG &gt; GG, while C:P and N:P were shown as MG &gt; GG &gt; EG. The soil N:P ratios were all less than 14, indicating that all of them had an obvious N limitation. (3) Soil microbial biomass carbon (MBC) was GG &gt; MG &gt; EG. Soil microbial biomass nitrogen (MBN) was GG &gt; EG &gt; MG. Soil microbial biomass phosphorus (MBP) showed EG &gt; GG &gt; MG. MBC:MBN was MG &gt; EG &gt; GG. MBC:MBP was MG &gt; EG &gt; GG. MBN:MBP was GG &gt; MG &gt; EG. The MBN:MBP in GG and MG was greater than 9.6, which is P-limited, while the MBN:MBP in EG is less than 8.9, which is N-limited. (4) Plant C and N were significantly correlated with soil C and N, but plant P was significantly negatively correlated with soil P, while MBP was significantly positively correlated with soil TP. Soil microorganisms had the tendency to assimilate available P in GG and MG treatments, but the potential of releasing P from mineralized soil organic matter was higher in EG treatment. The results showed that the chemical properties and stoichiometric characteristics of the plant–soil–microorganism were significantly changed by different grassland-use methods, which provided scientific guidance for the management of C, N and P elements and the further optimization of soil microbial environment for artificial grassland in the karst rocky desertification area.

Promoting agroforestry on sand dunes for desertification control in arid regions

This research focuses on tackling the issue of fertile land turning into desert in arid regions. It proposes a solution involving financial incentives based on payment for ecosystem services (PES) to encourage the transformation of privately owned sand dunes into agroforestry systems. Under the proposed mechanism, farmers plant Acacia nilotica trees along with pearl millet on sand dunes, which provides resilient economic returns in regions with harsh climatic conditions. In addition, acacia trees help to prevent crop damage on neighboring farms through stabilizing sand dunes and serving as shelterbelts. A dynamic optimization model of land-use decisions between open millet farming and acacia-based agroforestry derives optimal afforestation of sand dunes under varying PES payments, crop incomes, and farm size endowments. Results suggest that such agroforestry systems can be effective towards preventing the spread of desertification in arid regions. Further, PES incentives can improve agroforestry uptake as well as augment farmers’ livelihoods.

Versatile Quasi‐Solid Ionic Conductive Elastomer Inspired by Desertification Control Strategy for Soft Iontronics

AbstractIonic conductors, such as hydrogels, ionogels, and eutectogels, have attained considerable research interest in various advanced application scenarios. However, such ionic conductors still suffer from the restriction of inherent liquid compositions, which may leak or evaporate. Herein, inspired by the control strategy of desertification caused by soil erosion, a novel internal‐external dual enhancement design strategy, i.e., increasing the interaction between the filler itself and its matrix, is proposed to firmly embed the deep eutectic solvent (DES) into polyurethane (PU) to prevent liquid leakage, such that the prepared ionic conductive elastomers (PU‐DESs) are quasi‐solid. The PU‐DESs exhibit marvelous versatility including high stretchability, tensile strength, toughness, self‐healing efficiency, antibacterial ability, ionic conductivity, and excellent freezing tolerance. More intriguingly, benefiting from their quasi‐solid feature, PU‐DESs are endowed with long‐term environmental stability. Thanks to these superb versatile features, PU‐DESs are further successfully applied in the wearable sensor and triboelectric nanogenerator (TENG) for monitoring human motions and converting mechanical energy into electrical energy, breaking away from the limitations of previous most soft iontronics such as liquid leakage or evaporation and weak mechanical strength. Hence, this study establishes an effective material design strategy for various soft iontronics demanding environmental stability and durability.

Forest Ecosystem Service Trade-Offs/Synergies and System Function Optimization in Karst Desertification Control.

Karst desertification control forests are essential for ecosystem multi functionality, but the trade-offs/synergies are unclear for forest ecosystem services. In order to clarify the trade-offs/synergies, this study was conducted on eight forest communities in a karst desertification control area and was based on vegetation surveys and structural and functional monitoring. It analyzes water holding capacity, species diversity, soil conservation, and carbon storage characteristics and their trade-off/synergies. The results indicate the following: (1) The Cladrastis platycarpa + Cotinus coggygria community (H1) had the highest water holding capacity and species diversity with values of 252.21 t·hm-2 and 2.56, respectively. Soil conservation was highest in the Zanthoxylum bungeanum + Glycine max community (H6), with an index value of 1.56. Carbon storage was the greatest in the Tectona grandis community (H8), at 103.93 t·hm-2. The results of these studies have shown that there are significant differences in different types of forest community ecosystem services. (2) Water holding capacity, species diversity, soil conservation, and carbon storage, all have synergistic relationships, suggesting a trend towards synergistic enhancement between the services. (3) The species diversity of the forest ecosystems was shown to be in a trade-off with carbon storage and soil conservation, which suggests that the services are in competition with each other. To further improve the service capacity of forest ecosystems, the trade-offs between the regulation of forest community structure and function and the improvement of services should be optimized.

Correlation between Non-Structural Carbohydrates and C:N:P Stoichiometric Ratio of Haloxylon ammodendron under Different Water–Salt Gradients

Growth is restricted by both water and phosphorus (P), and balancing the relationship between non−structural carbohydrates (NSCs) and carbon: nitrogen: phosphorus (C:N:P) is essential for Haloxylon ammodendron to adapt to arid habitats. The survival and growth strategies of the dominant species H. ammodendron in a desert ecosystem were examined in order to better serve the restoration of degraded ecosystems and desertification control. Three water and salt gradients (high water and high salinity, medium water and salinity, and low water and low salinity) in the Aibi Lake Reserve were selected. We analyzed the accumulation and distribution of NSCs in the assimilation branches and secondary branches of H. ammodendron and the changes in the measurement ratio characteristics of C:N:P, as well as the soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) content. The results showed that: (1) With the decrease of soil water and salt content, the basal diameter, plant height, crown area, and NSC content of H. ammodendron significantly decreased. This morphological adjustment in the aboveground part is similar to a “self thinning” behavior, aimed at reducing transpiration area and balancing carbon distribution in the body. The carbon accumulation in the body helps the H. ammodendron to resist the dual stresses of drought and salt. (2) With the decrease of water and salt content, the C content of assimilating branches increased significantly, while there was no significant change in secondary branches. However, the N and P content of both branches decreased significantly, and the N: P of both branches was greater than 16, indicating that it was mainly limited by P. (3) The NSC of the two branches was significantly negatively correlated with C, and significantly positively correlated with N and P, and there was a strong positive correlation between the assimilation branches NSC: C: P and NSC: C: P. The synthesis and accumulation of NSC of H. ammodendron were influenced by the content and relationship of C, N, and P, and the abundance of P content transported by the root system to the aboveground portion may have an important and decisive role in regulating nutrient balance and non-structural carbon dynamics.