To investigate the effect of phosphorus fertilization on the regulation of photosynthetic and fruiting characteristics of winter wheat under different water treatments,and to clarify the mechanism of phosphorus application to regulate the photosynthetic productivity and promote the development of spike floret development into grains,three water treatments(severe drought treatment,W0;moderate drought treatment,Wl;and normal water treatment,W2)and two phosphorus fertilizer treatments(no phosphorus fertilizer treatment,P0;and phosphorus fertilizer treatment,P1)were set up in 2020-2022 for pot experiment.Using the massive-spike variety Zhoumai 16(V1)and the multi-spike variety Yumai 49-198(V2)as experimental materials,we analyzed the effects of phosphorus on the photosynthetic and fruiting characteristics of winter wheat of the two types of varieties under different water treatments by determining the number of fertile florets and the number of grains in the different spikes(the basal,the central,and the apical parts of the spikes),as well as the net photosynthetic rate,chlorophyll content,chlorophyll fluorescence parameter,and sucrose content of leaves.The results showed that the phosphorus fertilization could effectively increase the number of fertile florets at anthesis(W10 stage)in winter wheat,especially the most significant effect on the number of fertile florets at the basal spike position(13.74％—27.01％),followed by the top(9.57％—20.19％),and then the middle(6.97％—14.01％).For the number of grains at maturity,the phosphorus fertilizer application increased the number of spikelets per spike as well as the number of grains in each spikelet under drought stress,and then significantly increased the number of grains.In addition,the phosphorus fertilization was effective in increasing the net photosynthetic rate,chlorophyll content,photosystem Ⅱ maximum photosynthetic efficiency(Fv/Fm)and actual photochemical efficiency(ΦPSⅡ)of leaves of both types of varieties,and the effects on sucrose content varied according to water treatments,with phosphorus fertilization decreasing the sucrose content under drought treatments,and increasing the sucrose content under normal water treatments.Pathway analyses of the photosynthetic indexes of the two types of varieties with the number of fertile florets and the number of grains per spike respectively revealed that five photosynthetic indexes were positively correlated with the number of fertile florets and the number of grains per spike,among which the direct pathway coefficients of Pn and sucrose with the number of fertile florets were 1.001 and 0.435,and those with the number of grains were 0.996 and 0.626,which were much higher than those of other indexes.Finally,phosphorus application significantly increased yield by increasing spike number,grain number per spike and 1000-grain weight,among which grain number per spike reached significant level under different water treatments,spike number was significant under W1 and W2 treatments,and 1000-grain weight improvement effect was not significant.In summary,the application of phosphorus fertilizer under different water treatments could improve the photosynthetic productivity of winter wheat by regulating its photosynthetic performance to maintain normal physiological and metabolic functions,thus reducing the degradation and abortion of fertile florets and promoting the spike floret develop into grains,ultimately alleviating the damage caused by drought stress for the purpose of achieving high and stable yields.The results provide a theoretical basis and technical support for alleviating the adverse effects of drought stress on wheat growth through the application of phosphorus fertilizer.
Yongle Atoll was the largest atoll in the Xisha Islands of the South China Sea, and it was a coral reef ecosystem with important ecological and economic values. In order to better protect and manage the coral reef fish resources in Yongle Atoll, we analyzed field survey data from artisanal fishery, catches, and underwater video from 2020 to 2022 and combined historical research to explore the changes in fish species composition and community structure in Yongle Atoll over the past 50 years. The results showed that a total of 336 species of fish were found on Yongle Atoll, belonging to 17 orders and 60 families. Among them, Perciformes had the most fish species with 259 species accounting for 77.08% of the total number of species. The number of fish species in the coral reef of Yongle Atoll was exponentially correlated with its corresponding maximum length and significantly decreases with its increase. The fish community structure of Yongle Atoll changed, and the proportion of large carnivorous fish decreased significantly, while the proportion of small-sized and medium-sized fish increased. At the same time, Yongle Atoll has 18 species of fish listed on the IUCN Red List, 15 of which are large fish. The average taxonomic distinctness (Delta+, Δ+) and the variation taxonomic distinctness (Lambda+, Λ+) in 2020–2022 were lower than the historical data, and the number of fish orders, families, and genera in Yongle Atoll has decreased significantly, which indicates that the current coral reef fish species in Yongle Atoll have closer relatives and higher fish species uniformity. In addition, the similarity of fish species in Yongle Atoll was relatively low at various time periods, further proving that the fish community structure has undergone significant variation. In general, due to multiple impacts, such as overfishing, fishing methods, environmental changes, and habitat degradation, the fish species composition of Yongle Atoll may have basically evolved from carnivorous to herbivorous, from large fish to small fish, and from complexity to simplicity, leaving Yongle Atoll in an unstable state. Therefore, we need to strengthen the continuous monitoring of the coral reef ecosystem in Yongle Atoll to achieve the protection and restoration of its ecological environment and fishery resources, as well as sustainable utilization and management.
In recent years, transgenic technology has developed rapidly, but the risk of the environmental release of transgenic organisms is still a key issue. Research on the impact on biodiversity is an effective way to objectively evaluate the risk. By taking transgenic maize HGK60 with insect-resistant gene Cry1Ah and common maize Zheng 58 as control, a 2-year experiment of arthropod community biodiversity in fields of them were studied using three methods.in 2019 and 2020. The results showed that a total of 124 species and 38537 individuals were observed from the experiment, belonging to 11 orders and 40 families. There was no significant difference in the individual number and species number of herbivorous, predatory and parasitic groups in the two kinds of maize in two years. Only the individual number of HGK60 was significantly higher than that of common maize Zheng 58 at heading stage in 2019. And the percentages of individual number and species number in different groups were basically the same in the two kinds of maize at each stage in two years. Analyses of Richness index, Shannon-Wiener diversity index, Dominance index and Evenness index showed no significant difference between the two kinds of maize in two years. The similarity coefficient of the arthropod community suggested that the arthropod community composition of HGK60 was similar to that of common maize Zheng 58. Furthermore, HGK60 had no significant effect on the relative stability of the arthropod community. These results indicated that despite the presence of a relatively minor difference in arthropod community between the two kinds of maize, the planting of HGK60 had little effect on arthropod community biodiversity. The results provided some data and support for the further studies of environmental risk of transgenic crops.
Developing modern circular agriculture is helpful to promote the high ̄quality transformation of agricultural production mode in Chinaꎬ which is one of the important ways to realize agricultural sustainable development. Howeverꎬ when the agricultural production operators applied the circular agriculture model to the particular system constructionꎬ there often occurred problems such as unknown input and outputꎬ low circulation efficiency and lack of overall evaluationꎬ which led to obstacles for the efficient operation and material ̄energy utilization of modern circular agriculture systems. In this studyꎬ the modern “straw ̄sheep ̄cropland” agro ̄pastoral circular system of Donglin Village in Jiangsu Province was selected
温带荒漠积雪覆盖是土壤含水量增加的重要方式，在冻融期带来丰富的水分变化。全球气候变化导致温带荒漠积雪深度时空格局发生改变，从而影响荒漠生态系统温室气体的通量。生物结皮在维持荒漠生态系统结构和功能的稳定具有非常重要的作用，但对环境的变化较为敏感，尤其是降水变化。然而，目前有关冻融期不同积雪条件下生物结皮温室气体通量的研究十分匮乏。CH 4 是重要的温室气体，选择古尔班通古特沙漠藓和地衣2种类型生物结皮为研究对象，以裸沙为对照，设置增雪、自然降雪（对照）和除雪三种处理，通过静态箱-气相色谱法，探究CH 4 通量在冻融期的变化特征。结果表明：冻融期多数情况下积雪处理和结皮类型对CH 4 通量影响不显著。荒漠生物结皮对CH 4 整体表现为吸收作用，是荒漠生态系统CH 4 重要的“汇”。两种结皮类型及裸沙CH 4 的吸收速率呈现为地衣结皮(-10.12μg m -2 h -1 )＞藓结皮(-1.73μg m -2 h -1 )＞裸沙(-1.69μg m -2 h -1 )。CH 4 通量通常与土壤5 cm深处的温度和水分的相关性不显著，对其他土壤理化因子响应较弱。研究结果表明，积雪处理不会对冻融期生物结皮CH 4 通量产生显著影响，全球变化条件下温带荒漠积雪的改变可能对土壤CH 4 的产生和吸收影响较小。
连栽导致土壤退化是制约杉木初级生产力实现的重要障碍因素，而土壤对病原菌的抑制能力决定着植物能否有效抵御病原菌侵害，是人工林土壤地力状况的重要表现。以一代、二代、三代杉木人工林和天然次生林为对象，采用平板隔空、直接对峙的方法，分析了不同代际杉木林土壤细菌群落对尖孢镰刀菌和立枯丝核菌的抑制能力。进一步利用高通量测序技术，研究了杉木林土壤细菌群落影响土壤抑病能力的生态过程。结果表明：土壤磷元素随连栽呈显著积累趋势，而土壤pH和有机质（SOM）等含量随连栽代数的增加而下降，但这些下降指标在三代杉木林与天然林土壤间无显著差异。而杉木连栽导致土壤对病原菌的抑制能力逐代降低，天然林土壤较杉木人工林对病原菌具有显著的高抑制能力。同时杉木连栽显著改变了土壤细菌群落组成，而对群落整体α-多样性影响较小，说明土壤中一些关键类群对杉木连栽响应的敏感性高于整体细菌群落的变化。进一步利用随机森林模型预测与回归分析，揭示了杉木连栽引起的土壤一些关键细菌类群丰度的降低是土壤抑病能力下降的重要原因，这些类群主要受土壤pH、SOM、TP等土壤理化因子的调控。由此，杉木长期连栽会引起土壤微环境失衡，致使土壤抑制病原菌能力下降，从而增加病原菌危害杉木林健康，不利于人工林生产力的提升和可持续经营。
水资源是基础性自然资源和战略资源，科学量化水资源供给服务的供需关系、识别供需矛盾的突出区域是进行流域水资源管理的重要前提。以大清河流域为例，利用InVEST模型，建立了水资源供给服务空间流动量化方法，预测了用水效率提升、节水灌溉两种节水政策情景对水资源供给服务供需关系的影响。结果表明：（1）流域水资源供给服务和水资源需求量均呈现出上游低、下游高的空间分布格局，农业用水为流域主要用水类型，2010—2015年，流域水资源供给服务增长0.97%,水资源需求量出现了9.6%的下降；（2）2010—2015年，流域整体水资源供给服务的供需比由0.78提升至0.88,服务的空间流动使得上游盈余的水量缓解了中下游的用水压力，但中下游水资源需求大于供给的问题仍普遍存在；（3）提升用水效率、推行节水灌溉这两种节水政策均能够有效改善大清河流域的水资源供需关系，分别可将流域水资源供需比提升至0.97和0.96,基本达到供需平衡。研究可为北方资源型缺水流域水资源供需匹配度的提高、节水政策潜力的评估提供借鉴。
Metal toxicity can negatively affect aquatic biodiversity. In this study, eight trace metals (TMs) (Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) were determined in 72 sediment samples collected from six major rivers in Southwestern Nigeria between the dry and wet seasons of 2019 and 2021by inductively coupled plasma optical emission spectrometry (ICP-OES). Pollution indices such as enrichment factor, geo accumulation index, pollution load index, and potential ecological risk index were evaluated. At both seasons, the mean TM concentrations (mg/kg) followed a similar trend in decreasing order as Cu (589.32 +/- 582.00) > Fe (269.52 +/- 127.09) > Zn (162.68 +/- 103.14) > Mn (61.89 +/- 29.87) > Pb (10.09 +/- 5.34) > Cd (8.59 +/- 2.20) > Cr (8.72 +/- 2.60) > Ni (3.16 +/- 1.55) across locations and seasons. Distinctive distribution profiles characterized individual metals coupled with significant seasonal shifts in concentration ( p < 0.05). Comparison with recommended national limits for Cd, Cu, Fe, Ni, Pb, and Zn suggested potential human and ecosystem health risks for the local population, while all the metals are above US EPA residential criteria. Cd displayed considerable, or very high ecological risks across all locations and seasons. Overall, Cd was considered a key potential ecological risk factor. Data revealed more anthropogenic than natural sources influenced sediment-bound TMs based on principal component analysis (PCA) and positive matrix factorization (PMF). The findings in this report provide fundamental information that would allow more effective monitoring through the establishment of critical policies and measures to reduce TMs levels in the environment.
Historically, numerous plants have been used to alleviate various diseases, particularly viral diseases (bronchitis, influenza virus and dengue virus). This review evaluated their therapeutic potential against Covid-19 and mapped the 10 most studied plants during the pandemic. The standardized protocol for systematic reviews (PRISMA-P) was developed in this study. All studies involving medicinal plants and their potential against Covid19 infection were also considered. Two specific search fields "traditional medicine and Covid-19" and "medicinal plants and Covid-19" with appearance in the title, abstract and keywords were used to search for information. Only papers (review and original) published between 2020 and October 2021 were included. Short communications, letters to the editor, books and book chapters were excluded. A total of 24,046 articles were recorded among the four databases and an increase of 69% in publications for the 2021 search date, a higher percentage compared to the previous year (31%). China was the country with the highest production with 28% (2725 papers). The analysis of variance showed that the number of studies of Nigella sativa L. (1.62 +/- 0.21; p = 0.02), Glycyrrhiza glabra L. (1.50 +/- 0.32; p = 0.03), Zingiber officinale Roscoe (1.51 +/- 0.32; p = 0.03) were statistically significant with respect to the other species. This is probably because these species show compounds with high antiviral spectrum. Despite the pharmacological potential found in medicinal plants, more large-scale clinical trials are still needed to demonstrate the efficacy of phytocompounds against viral diseases.
Regional ecological safety is of great significance in coordinating the relationship between land use and ecological environmentꎬ promoting the rational allocation of resources and achieving the coordinated regional development. Taking the Lanzhou ̄Xining urban agglomeration (LXUA) as a typical areaꎬ this paper applies Morphological Spatial Pattern Analysis (MPSA) to study the optimal configuration of land use functionsꎬ and provides new ideas for regional layout optimization by constructing the MSPA ̄GMOP ̄PLUS coupling model to incorporate ecological security into the optimization of land use functions and spatial structure of urban agglomerations. The results show that: (1) the ecological source areas are of great significance to regional ecological securityꎬ and there were 20 ecological source areas in the LXUA in 2020ꎬ with an ecological core area of 43ꎬ355.5 km . In additionꎬ the ecological protection zone still accounts for the largest area (30.7%) in the functional land use zoningꎬ and the ecological fringe area also accounts for 19.2%ꎬ providing a buffer zone for the ecological protection. (2) The new simulation model can limit the unbalanced development trend of urban agglomerations
Gibberellins (GA3), as well as the basic elements phosphorus (P), nitrogen (N), and potassium (K), are crucial to the growth of chili. This study investigates the effect of different fertilizers and plant growth regulator on the growth and morphology of chili seedlings. Soil application of NPK, urea, SOP, and DAP (2.5 g/L) was applied during sowing, and N in two splits at sowing and after twenty days of sowing while foliar application of GA3 (50 mg/L) was applied after fifteen days of germination. The result of five seedlings' traits plant height (PH), plant girth (PG), plant spread (PS), number of leaves (NOF), and root length (RL) demonstrated a significant difference among growth-related traits in chili seedlings owing to the use of fertilizers, GA3, and their combinations. An optimum level of K and P alone or in combination with GA3 had a significant effect on all traits. PH was particularly influenced by the combination of GA3 with K and P whereas other traits like PG, NOF, PS, and RL are greatly influenced by the application of NPK, urea, SOP, DAP, and their combination with GA3. The study results showed an increase in chili seedlings' growth and morphology in response to various fertilizers and GA3.
The larval pupation site preference (PSP) of five Drosophila species belonging to three groups: cold-adapted (Drosophila nepalensis and D. simulans), warm-adapted (D. ananassae and D. virilis), and generalist (D. melanogaster) were analysed in laboratory conditions relative to both humidity and temperature. Our results showed that PSP differ significantly under different humid conditions. Irrespective of temperature, in dry con-ditions (40% humidity) larvae preferred to pupate on food (97% in cold adapted species and 60% in warm adapted species) whereas in wet conditions (80% humidity), larvae preferred to pupate away from food (58% in cold adapted species and 85% in warm adapted species). Drosophila melanogaster being a generalist species switched its PSP on-fruit to off-fruit from low to high humidity, respectively. We observed high digging behavior (99% diggers) in larvae of cold adapted species whereas warm adapted species exhibited low digging behavior (44% diggers). These results suggest that humidity along with digging behavior are the major factors affecting the PSP in Drosophila species.
Background: The undocumented indigenous knowledge of Kuki-Chin tribes within the fringe villages of Kaihlam Wildlife Sanctuary (KWLS) is vanishing without a trace, therefore preserving the valuable assets is critical for future generations.Methods: Ethnomedicinal information was collected from 84 informants from Kuki-Chin tribes (Paite, Thadou, Hmar, Gangte, Simte, Vaiphei and Zo) and quantitatively analyzed using ICF (Informant consensus factor), FL (Fidelity level), UV (Use value) and RFC (Relative frequency of citation).Results: The total ethnomedicinal plants reported include 102 plant species under 90 genera in 55 families and were utilized by the different ethnic groups of Kuki-Chin tribes in the present study. These plants were used against 53 different ailments grouped into 16 categories. The most commonly used plant part was represented by leaves (45%) and the most common form of preparation was decoction (41%). The calculated ethnobotanical indices range for informant consensus factor (ICF; 0.91-0.99), fidelity values (FL; 84%-100%), use value (UV; 0.5-0.9), the relative frequency of citation (RFC; 0.01-0.71) and the Pearson correlation coefficient between UV and RFC reflecting a positive correlation (0.788) between use value and the relative frequency of citation. The unique features of the study area were the perspectives for the corpse preservation, deworming in children, trichinosis and food poisoning remedies. Among the reported ethnomedicinal plants, two threatened taxa Cycas pectinata Griff. and Dillenia pentagyna Roxb. were highly utilized by the tribal communities as good source of medicines and food which need to be highlighted for their sustainable utilization and conservation.Conclusion: The ethnomedicinal plants were analyzed quantitatively for the first time from the study site regarding their indigenous use by different ethnic groups belonging to Kuki-Chin tribes in Kaihlam Wildlife Sanctuary. The present study will help in the conservation of such intangible assets for their sustainable utilization and prospecting for discovery of new drugs based on the traditional knowledge.
Field-based evaluation of indicator weed species in agriculture systems is effective for developing site-specific weed management. Because of anthropogenic activities and climate change, new weeds are invading agricultural fields. The current study examined the weed species in agricultural fields with a focus on diversity, distribution ecological patterns, and identification of indicator species, all of which might help in effective weed management practices. Following the calculation of the Importance Value Index for each weed species, ordination, and indicator species analysis were conducted. We collected vegetation data through random sampling, and the current study recorded 47 species, taxonomically distributed across 41 genera and 19 families. Asteraceae with 13% of species was the leading family followed by Poaceae, and Brassicaceae (11% each). Annual weed species with 49% were the dominant life span category. The phytogeographical analysis revealed that the highest number (28 species) recorded from the study area were native, while 19 species were alien. Of the total alien species, 4 were invasive, and 14 were naturalised and one species Bassia scoparia was casual. The diversity indices show significant differences (p ≤ 0.05) in weeds in rice fields recorded from the study area. Detrended correspondence analysis grouped the species Geranium rotundifolium, Sisymbrium loeselii, Mentha longifolia, Rumex dentatus, Amaranthus viridis on the extreme left side suggest a low score on axis 1 and a high score on axis 2. The analysis of indicator species revealed a significant difference (p ≤ 0.05) in agriculture fields across the sampled sites. According to the indicator species analysis, Poa annua, Persicaria hydropiper, Ranunculus sceleratus, and Echinochloa colona were the key weed species found in the study area. This investigation might aid weed management strategies to minimize crop losses and increase of rice production to fulfill the current food requirement.
Soil salinization due to inadequate land management is considered one of the main threats to the sustainable development of agroecosystems in arid and semiarid regions. Approximately 20% of irrigated areas in the word are threatened by secondary soil salinization. To explore the influence of land use-land cover (LULC) on soil water and salinity in those regions, farmland areas planted with spring-sown wheat (Triticum aestivum L.) or alfalfa (Medicago sativa L.), and bare land (CK) in the Qinwangchuan irrigated region of Gansu Province in China were selected as the research objects. The characteristics of surface vegetation (coverage, height, biomass), surface micro-environmental factors (light intensity, soil temperature) and soil physicochemical properties (moisture and salinity) were measured successively for four years, and their changes and quantitative relationships were analyzed. The results showed that the coverage, height, and biomass of surface vegetation (or stubble) under different LULCs in spring and autumn were significantly different (p < 0.05) and ranked as follows: alfalfa field > wheat field > bare land. With the increasing surface vegetation, the surface light intensity and topsoil temperature at a depth of 5 cm indicated decreasing trends; the water content in the 0–5-cm soil layer showed an increasing trend, while that in the 0–40-cm layers displayed the opposite trend; the salinity at depths of 0–5 and 0–40 cm indicated a decreasing trend. Correlation analysis showed that there was a significant negative correlation between the vegetation characteristics and the salinity in the 0–5- and 0–40-cm soil layers (p < 0.01), while opposite correlations were observed between the vegetation characteristics and the water content in the 0–5- and 0–40-cm soil layers. Regression analysis showed that a 1% increase in vegetation coverage would decrease the salinity at depths of 0–5 and 0–40 cm by 2.5 and 1.0 uS.cm−1, respectively. In summary, farmland planted with spring-sown crops with short growth periods or abandoned in semiarid and arid irrigated regions would gradually experience an increase in soil salinity, whereas the planting of perennial alfalfa could inhibit and lessen soil salt accumulation at depths of 0–5 and 0–40 cm, which is beneficial to improve the soil quality. In addition, this study also revealed the change rule of soil salts under different LULCs in semiarid regions, the fastest increasing stage of topsoil salts, and the importance of surface vegetation and stubble cover in controlling soil salinization.
In response to global warming issues, the entire world community seeks to decarbonize its energy and economy. One of the ways to reduce concentrated greenhouse gases in the atmosphere is to enlarge forest areas and encourage forest regeneration after fires. The given paper describes sterilization methods of primary explants. Studies have shown that 0.1% diacid solution supplemented with Tween 20 is the most effective at producing aseptic viable cultures of triploid aspen (Populus tremula L.) in vitro. This method provides the necessary amount of viable sterile cultures for their subsequent micro-multiplication (clonal), sufficient for the further mass production of planting material. Murashige & Skoog (MS) medium supplemented with 6-benzylaminopurine (BAP) had a more intensive formation of adventive buds compared to the medium with kinetin. Higher BAP concentration resulted in more regenerants from one explant with their height shortened. Woody Plant Medium (WPM) with different concentrations of 6-benzylaminopurine and indolyl-acetic acid (IAA) is more effective for working with triploid aspen. Effective reproduction at triploid aspen cultivation was shown at 0.5 mg/l concentration of BAP. The research results can be successfully used in vitro culture introducing of triploid aspen, experiments on micro-reproduction of other tree crops to get high-quality planting material.
Habitat loss and fragmentation have widely recognised as the major challenge for biodiversity conservation across the world. This is particularly true in Quirimbas National Park (QNP) where holds unique fauna, and anthropogenic factors have been intensifying leading to a significant loss of biodiversity, especially rodents which play a vital role for the functioning of ecosystems. However, studies assessing rodent diversity, and deeply analysing spatiotemporal dynamics of this vulnerable landscape are still lacking although they are decisive for successful wildlife management and monitoring. This study aimed to assess the rodent diversity, change intensity and its driving forces, and fragmentation of different habitat types in QNP. Multi -temporal satellite images and field data were used to analyse the habitat fragmentation and change intensities at three levels (time interval, category, and transition) from 1990 to 2020. The stratified sampling and capture-recapture approaches were used to survey rodents in three habitats: forest, grassland and cropland. Ecological metrics were employed to measure rodent diversity, distribution and composition. Statistical tests were applied to check differences in rodent abundance and diversity among habitats. The findings revealed an increase in fragmentation of all habitats, and forest experienced the highest losses (107.3 km 2 ) during 1990 - 2020. The annual rate change intensity was fast from 2010 to 2020. Cropland and built-up land experienced greater intensively gains and losses, while the annual change intensity of forest was dormant over time. Cropland and built-up land expanded at the expense of forest from 2010 to 2020, whereas from 2000 to 2010, cropland ' s gain targeted intensively grassland, built-up land and water body, and avoided forest. We recorded four rodent species: Acomys spinosissimus , Mastomys verreauxii , Dasymys incomtus and Aethomys chrysophilus ; the last three species are new records for the park. Forest revealed the highest rodent diversity (Shannon entropy = 3.0), and the total species richness was comparable to previous studies in eastern Africa. We found significant differences in rodent abundance among habitats. Turnover and nestedness were the main cause of the overall beta diversity. This study can provide vital information for wildlife managers to better understand the process of habitat loss and fragmentation and its implication to biodiversity, which is crucial for applying appropriate conservation management.
The present study documented the floristic diversity of Binsar Wildlife Sanctuary, Uttarakhand, India. A total of 604 vascular plants belonging to 421 genera and 103 families were reported. Poaceae was the dominant family followed by Asteraceae, Fabaceae, Lamiaceae and Rosaceae whereas Crotalaria, Eragrostis and Euphorbia were the dominant genera. Herbaceous forms were the dominant growth forms representing 54% of the total plants followed by shrubs (16%), grasses (13%), trees (8%), climbers (3%), orchids and sedges (2%). Out of the total documented plant species, 03 species were endemic and 44 species were near endemic to Indian Himalayan Region. Based on threat assessments, 13 plant species were categorized to be threatened represented by 02 Endangered, 07 Vulnerable and 04 Least concern species. In view of conservation of plant diversity proper monitoring, awareness programs and appropriate management plans required for conserving the natural ecosystem.
In the tropical dry deciduous forests of Central India, changes in population structure and regeneration of a Near Threatened tree Pterocarpus marsupium Roxb. (Fabaceae) was monitored over 4 years. Focussing on the effects of biotic disturbance, the study examined seven potential sites, for future restoration measures and management. We examined 46 plots of 0.1 ha size laid in these seven sites from 2017 to 2021. Results compared in all sites revealed that there were hardly any individuals surviving or growing at 'Sapling' stage, which is counted as crucial for successful regeneration of a tree species. Among all the study sites, SARA recorded highest average density of seedlings per sample plot followed by BAHO and LAMT. Positive change in 'Seedlings' category was recorded only at BAHO (+17.8%) and SARA (+9.1%). Whereas, BIRS recorded highest decline in average density of seedlings (-42.2%) followed by SEMA (-24.3%) and BARH (17.2%). Correlation analysis of biotic pressure on the species, revealed that weed infestation (-0.59) has highest adverse effect on the seedling density followed by Lopping/cutting (-0.33) and livestock & human population (-0.12), indicating an urgent need to undertake assisted natural regeneration (ANR) activities for this species in its natural ranges. Although there were few positive changes in the seedling stage (BAHO +17.8%; SARA +9.1%), but conditions of most sites did not meet the standards necessary for the survival and growth of a tree species. Therefore, the study concludes that lack of ability of seedlings to grow into saplings due to biotic pressure is the main limitation for the natural habitats of P. marsupium in Central India.
Rare earth elements (REE) are essential elements used in various products. Meanwhile, in several countries, REE is feared will pollute the ecosystem. The occurrences of REE in soil depend on the natural influence of the parent material. However, anthropogenic activities could also be responsible for REE enrichment in soil. To understand the effect of volcanic soil parent material (as a natural influence) and anthropogenic activities, we analyzed the enrichment and geoaccumulation factor of REE. The ecological risk index is used to obtain the potential REE contamination into ecosystem. The samples were taken from three Andisols soil profiles (Pangalengan, Lembang, and Wayangwindu) from the same quaternary volcanic rocks in West Java, Indonesia. REE content in Pangalengan soil varied from 0.25 mg kg-1 (Tm) to 73.50 mg kg-1 (Ce), Lembang soil ranged from 0.57 mg kg-1 (Tm) to 77.30 mg kg- 1 (Ce), and Wayangwindu ranged from 0.17 mg kg- 1 (Tm) to 77.30 mg kg- 1 (Ce). The enrichment of REE in all Andisols soils from three different sites (Pangalengan, Lembang, Wayangwindu) was classified as a deficiency to minimal enrichment. The geoaccumulation of REE is classified as moderately contaminated that occurs only in A horizon in Pangalengan soil. The REE enrichment seems closely related to anthropogenic factors, especially in A horizon at Pangalengan. Parent materials weathering is the most dominant factor in REE enrichment in the subsurface horizon for all sites but in the surface horizon in Pangalengan related to agricultural activities. The ecological risk index of REE was smaller than 40 (low risk), except for Lu in Pangalengan soil at moderate risk.
