Impacts of Climate Change and Human Activities on Plant Species α -Diversity across the Tibetan Grasslands

: Plant species α -diversity is closely correlated with ecosystem structures and functions. However, whether climate change and human activities will reduce plant species α -diversity remains controversial. In this study, potential (i.e., potential species richness: SRp, Shannonp, Simpsonp and Pieloup) and actual plant species α -diversity (i.e., actual species richness: SRa, Shannona, Simpsona and Pieloua) during 2000–2020 were quantiﬁed based on random forests in grasslands on the Tibetan Plateau. Overall, climate change had positive inﬂuences on potential plant species α -diversity across all the grassland systems. However, more than one-third areas showed decreasing trends for potential plant species α -diversity. Climate change increased the SRp at rates of 0.0060 and 0.0025 yr − 1 in alpine steppes and alpine meadows, respectively. Temperature change predominated the variations of Shannonp and Simpsonp, and radiation change predominated the variations of SRp and Pieloup. Geography position, local temperature, precipitation and radiation conditions regulated the impacts of climate change on potential species α -diversity. On average, human activities caused 1% plant species loss but elevated the Shannon, Simpson and Pielou by 26%, 4% and 5%, respectively. There were 46.51%, 81.08%, 61.26% and 61.10% areas showing positive effects of human activities on plant species richness, Shannon, Simpson and Pielou, respectively. There were less than 48% areas showing increasing trends of human activities’ impacts on plant species α -diversity. Human activities increased plant species richness by 2% in alpine meadows but decreased plant species richness by 1% in alpine steppes. Accordingly, both the impacts of climate change and human activities on plant species α -diversity were not always negative and varied with space and grassland types. The study warned that both climate change and human activities may not cause as much species loss as expected. This study also cautioned that the impacts of radiation change on plant species α -diversity should be at least put on the same level as the impacts of climate warming and precipitation change on plant α -diversity.


Introduction
Plant species α-diversity, as key components of biodiversity, is affected by both climate change and human activities [1][2][3][4], which in turn results in positive or negative feedback to the structure and function of ecological systems (e.g., forage nutrition quality and production, soil microbial diversity) at multiple spatial and temporal scales [5,6]. A large number of studies have been carried out to examine the impacts of climate change and human activities (e.g., nitrogen addition, grazing) on plant species α-diversity [3,4,[7][8][9][10][11]. Such studies can better provide services for conservating plant species α-diversity under the background of global change and improving the positive feedback strength of plant species α-diversity on the structure and function of ecosystems and even the high-quality development of human beings [12,13]. However, there are still two issues are needed to be resolved. Firstly, it is widely accepted that climate change has and will continue to affect plant species
Longitude, latitude, elevation, MAT, MAP, MARad, slope_AT, slope_AP and slope_ARad significantly explained the change rates of plant α-diversity, but their relative impacts were different ( Figures A3-A16). Compared to geography position and mean climate conditions, climate change had greater exclusive impacts on the change rates of plant α-diversity ( Figure 3). Compared to the change rates of actual plant α-diversity, climate change had greater impacts on the change rates of potential plant α-diversity ( Figure 3). The impacts of geography position and mean climate conditions on the change rates of potential α-diversity were different from those on the change rates of actual α-diversity ( Figure 3). Both the MNDVI max and slope_NDVI max were correlated with the change rates of actual α-diversity ( Figure A17).

Spatial Variations of RSR, RShannon, RSimpson and RPielou, and Their Correlations with Environmental Factors
The spatial average values of the human activities' effects on plant species richness Shannon, Simpson and Pielou were 0.99, 1.26, 1.04 and 1.05, respectively ( Figure 4). On average, there were 46.51%, 81.08%, 61.26% and 61.10% areas showing the positive effect of human activities on plant species richness, Shannon, Simpson and Pielou, respectively ( Figure 4). The effects of human activities on plant α-diversity varied with grassland type . Relative contributions of geography position (i.e., longitude, latitude and elevation), mean climate conditions (i.e., mean annual temperature, mean annual precipitation and mean annual radiation in 2000-2020) and climate change (i.e., change rate for annual temperature, annual precipitation and annual radiation in 2000-2020) to change rate of (a) potential species richness (slope_SR p ), (b) actual species richness (slope_SR a ), (c) potential Shannon (slope_Shannon p ), (d) actual Shannon (slope_Shannon a ), (e) potential Simpson (slope_Simpson p ), (f) actual Simpson (slope_ Simpson a ), (g) potential Pielou (slope_Pielou p ) and (h) actual Pielou (slope_Pielou a ).  Figure 4). The effects of human activities on plant α-diversity varied with grassland types (Table A2). For example, human activities increased plant species richness by 4% and 2% in alpine meadow-steppes and alpine meadows but decreased plant species richness by 1% and 3% in alpine steppes and alpine desert-steppes, respectively (Table A2).
Longitude, latitude, elevation, MAT, MAP, MARad, MNDVI max , slope_AT, slope_AP, slope_ARad and slope_NDVI max significantly explained the spatial variations of human activities' effects on plant species α-diversity, but their relative impacts were different ( Figures A18-A21). Compared to longitude and elevation, latitude had a closer correlation with the spatial variations of human activities' effects on plant species α-diversity ( Figure A21). Compared to geography position and climate change + slope_NDVI max , mean climate conditions + NDVI max had greater exclusive impacts on the spatial variations of human activities' effects on plant species α-diversity ( Figure 5). in alpine meadow-steppes and alpine meadows but decreased plant species rich 1% and 3% in alpine steppes and alpine desert-steppes, respectively (Table A2). Longitude, latitude, elevation, MAT, MAP, MARad, MNDVImax, slope_AT, slo slope_ARad and slope_NDVImax significantly explained the spatial variations of activities' effects on plant species α-diversity, but their relative impacts were d ( Figures A18-A21). Compared to longitude and elevation, latitude had a closer cor with the spatial variations of human activities' effects on plant species α-diversity A21). Compared to geography position and climate change + slope_NDVImax, m . Spatial patterns for (a) the ratio of mean actual species richness to potential species richness (Ratio SR ), (b) the ratio of mean actual Shannon to potential Shannon (Ratio Shannon ), (c) the ratio of mean actual Simpson to potential Simpson (Ratio Simpson ) and (d) the ratio of mean actual Pielou to potential Pielou (Ratio Pielou ).

Figure 5.
Relative contributions of geography position (i.e., longitude, latitude and elevation), mean climate conditions + NDVImax (i.e., mean annual temperature, mean annual precipitation, mean annual radiation and mean maximum normalized difference vegetation index during growing season in 2000-2020) and climate change + slope_NDVImax (i.e., change rate for annual temperature, annual precipitation, annual radiation and maximum normalized difference vegetation index during growing season in 2000-2020) to (a) mean effect of human activities on plant species richness (RatioSR), (b) change rate for effect of human activities on plant species richness (slope_RatioSR), (c) mean effect of human activities on plant Shannon (RatioShannon), (d) change rate for effect of human activities on plant Shannon (slope_RatioShannon), (e) mean effect of human activities on plant Simpson (RatioSimpson), (f) change rate for effect of human activities on plant Simpson (slope_RatioSimpson), (g) mean effect of human activities on plant Pielou (RatioPielou) and (h) change rate for effect of human activities on plant Pielou (slope_RatioPielou).

Temporal Changes in Human Activities Effects on Plant α-Diversity and Their Correlations with Environmental Factors
The spatial average values for the change rate of human activities effects on plant species richness, Shannon, Simpson and Pielou were −0.0004, −0.0011, −0.0011 and −0.0004, Figure 5. Relative contributions of geography position (i.e., longitude, latitude and elevation), mean climate conditions + NDVI max (i.e., mean annual temperature, mean annual precipitation, mean annual radiation and mean maximum normalized difference vegetation index during growing season in 2000-2020) and climate change + slope_NDVI max (i.e., change rate for annual temperature, annual precipitation, annual radiation and maximum normalized difference vegetation index during growing season in 2000-2020) to (a) mean effect of human activities on plant species richness (Ratio SR ),

Temporal Changes in Human Activities Effects on Plant α-Diversity and Their Correlations with Environmental Factors
The spatial average values for the change rate of human activities effects on plant species richness, Shannon, Simpson and Pielou were −0.0004, −0.0011, −0.0011 and −0.0004, respectively ( Figure 6). There were 42.40%, 43.97%, 44.65% and 47.88% areas showing increasing trends for the slope_R SR , slope_R Shannon , slope_R Simpson and slope_R Pielou , respectively ( Figures 6 and 7, Table 2). There were 51.96%, 53.88%, 53.68% and 50.22% areas showing decreasing trends for the slope_R SR , slope_R Shannon , slope_R Simpson and slope_R Pielou , respectively ( Figures 6 and 7, Table 2). The change rate of the human activities' effects on plant species α-diversity varied with grassland types (  Table 2). The change rate of the human activities' effects on plant species α-diversity varied with grassland types (Table A3).      Longitude, latitude, elevation, MAT, MAP, MARad, MNDVI max , slope_AT, slope_AP, slope_ARad and slope_NDVI max significantly explained the temporal variations of human activities' effects on plant species α-diversity, but their relative impacts were different ( Figures A22-A25). Compared to latitude and elevation, longitude had a closer correlation with the temporal variations of human activities' effects on plant species α-diversity ( Figure A25). Compared to geography position and mean climate conditions + NDVI max , climate change + slope_NDVI max had greater exclusive impacts on the temporal variations of human activities' effects on plant species α-diversity ( Figure 5).

Discussion
Some previous meta-analyses indicated that both climate change and human activities could cause a large loss of plant species in grassland ecosystems [10,19,34,35]. However, in this study, climate change increased plant species α-diversity across all the grassland ecosystems on the Tibetan Plateau. Human activities only caused about 1% species loss but increased the Shannon, Simpson and Pielou across all the grassland ecosystems on the Tibetan Plateau. Therefore, this study cautioned that both climate change and human activities might not cause as much species loss as expected.

Impacts of Climate Change on Plant Species α-Diversity
Our findings implied that climate change itself predominated the variations of plant species α-diversity, which was similar to some earlier studies [31,33]. However, whether temperature change, precipitation change and radiation change dominated the variations of plant species α-diversity varied with plant species α-diversity indicators. Temperature changes can have greater impacts on the variations of plant species α-diversity than precipitation change, which was in contrast with some earlier studies [29,36]. This phenomenon may be due to different spatial scales (these previous studies were only performed in some points, but this study was performed across all grasslands) and cautioned that precipitation change did not always have greater impacts than temperature change on grassland ecosystems on the Tibetan Plateau. Earlier studies focused on the impacts of precipitation change and warming but not radiation change on plant species α-diversity [14,30]. However, this study demonstrated that slope_ARad had exclusive impacts on and even predominated the change rate of potential α-diversity. This finding not only further supported some earlier studies [33,37] but also further cautioned that the impacts of radiation change on grassland ecological systems should be taken seriously enough on the Tibetan Plateau. Accordingly, temperature change, precipitation change and radiation change can affect the variations of plant species α-diversity, and their impacts on plant species α-diversity should not be ignored and should be highly valued.
Consistent with our Hypothesis, climate change did not always have positive or negative effects on plant species α-diversity, which was similar to some earlier studies performed in grassland ecological systems on [38,39] or outside the Tibetan Plateau [40,41]. This phenomenon was due to the following reasons. Firstly, an earlier study ascribed this phenomenon to the mutually weakening effects of heat and water resources and the regulating ability of climate change magnitudes and mean climate conditions on the impacts of climate change on grassland ecological systems [33]. Moreover, grassland types can also regulate the responses of plant species α-diversity to climate change [14,18]. Secondly, climate change can lead to the invasion of alien species from low elevation and/or low latitude [42,43], and plant species α-diversity may acclimatize to long-term climate change [39]. All these, in turn, can compensate for the possible negative impacts of climate change on plant species α-diversity. Thirdly, vegetative propagation may be the main propagation mode for alpine plants, but plant seed dispersal can still be an important mechanism for new plant colonization and plant community assembly. Climate change can lead to the increase or decline of plant seed yield [44][45][46] by altering plant phenology, which in turn can result in different impacts on plant seed dispersal ability and plant α-diversity. Fourthly, soil seed banks can play important roles in aboveground plant community regeneration [47,48]. Climate warming may increase plant species α-diversity by breaking the dormancy of soil seeds and stimulating their germination [49]. In contrast, climate warming may cause the loss of plant species α-diversity by the reduced soil seed α-diversity caused by climate warming [48]. Fifthly, climate change may alter the root-tostem ratio by altering the height of plant growth and water availability [50]. Sixthly, plant phyllosphere microorganisms and their host plants are coevolved, and the phyllosphere microbial communities can generally vary with host plants [51,52]. The effects of climate change on the phyllosphere microbial communities can vary among different plants, which in turn can have different feedbacks on the growth of plants, thus indirectly changing plant species α-diversity [53][54][55][56].
Our findings implied that the impacts of climate change on plant species α-diversity did not always decrease with decreasing precipitation, latitude and elevation and increasing temperature. This finding supported some earlier studies which demonstrated that the responses of forage nutrition quality to climate change did not always decrease with increasing temperature and decreasing precipitation and elevation [33,57]. This phenomenon was due to the following reasons. Firstly, an earlier study ascribed this phenomenon to the fact that the impacts of climate change on soil nutrition availability and microbial diversity did not increase with increasing elevation and decreasing temperature [33]. Secondly, the change trends of plant species α-diversity under climate change scenes were mainly correlated with the magnitudes of climate change, but climate change magnitudes were not linearly correlated with latitude, elevation, temperature and precipitation. Thirdly, local plant species pool and soil seed banks did not always increase or decrease linearly with increasing elevation/latitude [47][48][49], and the probability of transient disappearance/appearance of rare plant species and soil seed germination can be related to local plant species pool and soil seed banks under climate change scenes, respectively [17].
Consistent with our hypothesis, the impacts of climate change on plant species α-diversity varied with grassland types, which was similar to some earlier studies conducted in grassland ecological systems on the Tibetan Plateau [18,19]. This phenomenon was due to the following reasons. Firstly, both the local plant species pool and soil seed bank can vary with grassland types [29,47,48]. Secondly, plant diversity can be generally affected by both stochastic and deterministic processes [11,14,58]. Different types of grasslands have different dominant plant species and different assemblages of plant species [14]. Different plant species have different ecological niches and the capacity for sexual and asexual reproduction, which in turn may result in different reactions to temperature, precipitation and radiation change [59,60]. Accordingly, the impacts of climate change on the relative strengths of stochastic and deterministic processes in determining plant community assembly can vary with grassland types [14,43]. Thirdly, light, temperature, water and soil nutrition are four key and important resources of plants, and the availability of these four kinds of resources can vary among grassland types under climate change conditions [61][62][63]. All plants may compete for these four kinds of resources within a specific grassland community, and their competing intensity may vary with grassland types under climate change scenes. Fourthly, the responses of soil microbial diversity and soil pH to climate change can vary with grassland types [18,[64][65][66].
Our findings implied that climate change restructured the spatial distribution patterns of plant species α-diversity. Plant species α-diversity was closely correlated with forage nutrition quality, plant production, plant species β-diversity, plant phylogenetic αand β-diversity and soil pH [5,11,67]. Accordingly, this finding supported some earlier studies which demonstrated that climate change restructured the spatial distribution patterns of forage nutrition quality, plant aboveground plant production, precipitation use efficiency, plant species and phylogenetic diversity and soil pH in grassland ecological systems at various spatial scales on the Tibetan Plateau [14,33,59,66,68]. This phenomenon may be due to the following reasons. Firstly, an earlier study ascribed this phenomenon to the relative changes in the intensity of ecological processes (e.g., selection and dispersal) involved in plant community assembly and the recombination of environmental factors (i.e., temperature, water availability, soil nutrition and soil pH) under climate change scenes in alpine grassland ecological systems [14]. Climate change may cause a new spatial distribution of snow and ice, which are closely correlated with water availability [69][70][71][72][73]. Moreover, climate warming-induced reduction in wind speed may decrease the dispersal ability of wind-pollination plants [43]. Secondly, under the background of climate change, the spatial distribution range of plants varied with plant species, with increasing, decreasing and no change trends [59,60]. Thirdly, climate change may restructure spatial distribution patterns of soil seed banks [47,48] and soil microbial diversity [74].

Impacts of Human Activities on Plant Species α-Diversity
Our findings implied that human activities altered the impacts of climate change on plant species α-diversity. This finding supported some earlier studies [15,33,66] and was due to the following reasons. Firstly, both fencing and extra nitrogen addition, as two important ways of degrading grasslands restoration, can have different impacts on plant function groups [5,10] and, in turn, affect plant species α-diversity. Secondly, wild animals have been effectively protected based on the implementation of various protection measures, and their population structures and activity ranges have undergone a series of changes. Human activities are affecting and will continue to affect wild animals and, in turn, plant species α-diversity. Thirdly, livestock grazing can alter the relative importance value of different plant species and, in turn, species α-diversity through selective feeding of livestock [11] and feedbacks of livestock excreta and urine to soil nutrients (e.g., nitrogen and phosphorus). Fourthly, buying cultivated grass from non-local regions can relieve grazing pressure on local natural grasslands, and such human activities may not be mainly dependent on climate change.
Consistent with our Hypothesis, human activities did not always have positive or negative effects on plant species α-diversity, which was similar to some earlier studies performed in grassland ecological systems on [10,11] and outside the Tibetan Plateau [35]. This phenomenon was due to the following reasons. Firstly, soil seed banks were not always increased or decreased by human activities [75][76][77]. Secondly, yak dung is often collected by herders for fuel, but sheep/goat dung is generally left in place within the Tibetan grassland ecological systems [33]. The selective feeding preferences of different livestock are not identical. Accordingly, the impacts of human activities on plant species α-diversity can also vary with livestock species. Thirdly, both the intermediate disturbance hypothesis and Milchunas-Sala-Lauenroth mode can suggest that the intensity of human activities is related to the impacts of human activities on plant α-diversity [27,76]. Fourthly, the impacts of human activities on plant species α-diversity can vary with the duration of human activities [35].
Our findings implied that the impacts of human activities on plant species α-diversity varied with the year, which was similar to some earlier studies [35,78,79]. This phenomenon may be due to the following reasons. Firstly, the transition time between warm-season pastures and cold-season pastures is not completely fixed but varies with climatic conditions and vegetation phenology in grassland areas. The grazing scopes of livestock are also not completely static and can vary from year to year. Secondly, the reasonable carrying capacity based on the grass-livestock balance is relatively stable, but actual livestock numbers, forage yield, forage nutritional quality and the proportion of edible forage can be different over the years [33,36]. All kinds of ecological engineering are not done exactly in 1 year but in batches over several years for the Tibetan grassland ecological systems. Thirdly, both livestock structure (e.g., the ratio of yak to sheep) and population structure (e.g., age structure, gender structure) can change over time. Fourthly, the impacts of human activities on water, heat, light and soil nutrition resources and pH for plant growth can vary with years [11,66,78]. Fifthly, both the forage species and magnitude of buying cultivated grass from non-local regions and the forage species, scale and yield of cultivating grass in local regions can vary with years.
Consistent with our Hypothesis, the impacts of human activities on plant species αdiversity varied with grassland types, which was similar to some earlier studies conducted on [11,18] and outside the Tibetan Plateau [35]. This phenomenon may be due to the fact that the effects of human activities on the mechanisms of plant community assembly [11], soil seed banks [76], the ratio of root to stem, soil pH, soil water and soil nutrition can vary with grassland types [11,35,66].
Our findings implied that human activities reconstructed the spatial distribution patterns of plant species α-diversity. This finding supported some earlier studies which demonstrated that human activities restructured the spatial distribution pattern of forage nutrition quality and storage, plant species and phylogenetic diversity and soil pH in grassland ecological systems at various spatial scales on the Tibetan Plateau [5,11,33,66]. This phenomenon may be due to the following reasons. Firstly, the total population and the proportion of people from all walks of life (i.e., the population employment structure) have significant spatial variations on the Qinghai-Tibet Plateau [80]. For example, the number of people engaged in livestock grazing activities can partly determine the size and range of livestock grazing. Secondly, human activities can alter not only the local assembly mechanisms of plant communities but also community turnover among sites. However, these changes can vary with geography position [11]. Plant seeds can be spread in relatively large spaces by human activities such as the feeding behavior of livestock [81,82], but human activities (e.g., the type, size and activity scope of grazing livestock) can vary with geography position. Cold-season and warm-season grazing can generally have different impacts on plant species α-diversity [11,78], and their spatial scopes of warm-season pasture and cold-season pasture are often not completely coincident. Thirdly, human activities may reconstruct the spatial distribution patterns of water and soil nutrition availability and soil pH, and in turn, recombination of environmental variables under the disturbance of human activities [5,66,83]. Fourthly, human activities may alter the spatial distribution pattern of soil fungal communities [84]. Fifthly, both buying cultivated grass from the non-local region and cultivating grass in the local region are important human activities, and the two desires of farmers and herders can vary with geography position.

Conclusions
In summary, the impacts of climate change and human activities on plant species α-diversity were quantified during the past 21 years (2000-2020) of the Tibetan grasslands. This study implied that the spatial distribution patterns of plant species α-diversity were altered by both climate change and human activities. Climate change and human activities did not always have negative influences on plant species α-diversity, and their influences changed with space and grassland types. This study cautioned that the anticipated loss of species diversity due to climate change and human activity had been greatly exaggerated by previous studies, at least for the grasslands of the Tibetan Plateau. This study also cautioned that the impacts of radiation changes on plant species α-diversity should also be highlighted, besides warming and precipitation change. These findings may have certain theory and practice guiding significance, at least for biodiversity protection of the grasslands on the Tibetan Plateau.

Data Availability Statement:
The datasets generated for this study are available on request from the corresponding author.

Appendix A
Fixed Observation and Experiment Station of first Support System for Agriculture Green Development.

Data Availability Statement:
The datasets generated for this study are available on request from the corresponding author.                           . Correlations (a) between the change rate for the ratio of actual to potential species richness (slope_RatioSR) and longitude, (b) between the slope_RatioSR and latitude, (c) between the slope_RatioSR and elevation, (d) between the change rate for the ratio of actual to potential Shannon (slope_RatioShannon) and longitude, (e) between the slope_RatioShannon and latitude, (f) between the slope_RatioShannon and elevation, (g) between the change rate for the ratio of actual to potential Simpson (slope_RatioSimpson) and longitude, (h) between the slope_RatioSimpson and latitude, (i) between the slope_RatioSimpson and elevation, (j) between the change rate for the ratio of actual to potential Pielou (slope_RatioPielou) and longitude, (k) between the slope_RatioPielou and latitude and (l) between the slope_RatioPielou and elevation. Figure A22. Correlations (a) between the change rate for the ratio of actual to potential species richness (slope_Ratio SR ) and longitude, (b) between the slope_Ratio SR and latitude, (c) between the slope_Ratio SR and elevation, (d) between the change rate for the ratio of actual to potential Shannon (slope_Ratio Shannon ) and longitude, (e) between the slope_Ratio Shannon and latitude, (f) between the slope_Ratio Shannon and elevation, (g) between the change rate for the ratio of actual to potential Simpson (slope_Ratio Simpson ) and longitude, (h) between the slope_Ratio Simpson and latitude, (i) between the slope_Ratio Simpson and elevation, (j) between the change rate for the ratio of actual to potential Pielou (slope_Ratio Pielou ) and longitude, (k) between the slope_Ratio Pielou and latitude and (l) between the slope_Ratio Pielou and elevation.     Figure A24. Correlations (a) between the change rate for the ratio of actual to potential species ri ness (slope_RatioSR) and the change rate of annual temperature (ΔAT), (b) between the slope_Rat and the change rate of annual precipitation (ΔAP), (c) between the slope_RatioSR and the change r of annual radiation (ΔARad), (d) between the slope_RatioSR and the change rate of maximum n malized difference vegetation index (ΔNDVImax), (e) between the change rate for the ratio of act to potential Shannon (slope_RatioShannon) and ΔAT, (f) between the slope_RatioShannon and ΔAP, between the slope_RatioShannon and ΔARad, (h) between the slope_RatioShannon and ΔNDVImax, (i) tween the change rate for the ratio of actual to potential Simpson (slope_RatioSimpson) and ΔAT between the slope_RatioSimpson and ΔAP, (k) between the slope_RatioSimpson and ΔARad, (l) slope_RatioSimpson and ΔNDVImax, (m) between the change rate for the ratio of actual to poten Pielou (slope_RatioPielou) and ΔAT, (n) between the slope_RatioPielou and ΔAP, (o) between slope_RatioPielou and ΔARad and (p) between the slope_RatioPielou and ΔNDVImax. Figure A24. Correlations (a) between the change rate for the ratio of actual to potential species richness (slope_Ratio SR ) and the change rate of annual temperature (∆AT), (b) between the slope_Ratio SR and the change rate of annual precipitation (∆AP), (c) between the slope_Ratio SR and the change rate of annual radiation (∆ARad), (d) between the slope_Ratio SR and the change rate of maximum normalized difference vegetation index (∆NDVI max ), (e) between the change rate for the ratio of actual to potential Shannon (slope_Ratio Shannon ) and ∆AT, (f) between the slope_Ratio Shannon and ∆AP, (g) between the slope_Ratio Shannon and ∆ARad, (h) between the slope_Ratio Shannon and ∆NDVI max , (i) between the change rate for the ratio of actual to potential Simpson (slope_Ratio Simpson ) and ∆AT, (j) between the slope_Ratio Simpson and ∆AP, (k) between the slope_Ratio Simpson and ∆ARad, (l) the slope_Ratio Simpson and ∆NDVI max , (m) between the change rate for the ratio of actual to potential Pielou (slope_Ratio Pielou ) and ∆AT, (n) between the slope_Ratio Pielou and ∆AP, (o) between the slope_Ratio Pielou and ∆ARad and (p) between the slope_Ratio Pielou and ∆NDVI max .  Relative contribution of (a) longitude, latitude and elevation to the change rate for the ratio of actual to potential species richness (slope_Ratio SR ), (b) mean maximum normalized difference vegetation index (MNDVI max ), mean annual temperature (MAT), mean annual precipitation (MAP) and mean annual radiation (MARad) to slope_Ratio SR , (c) the change rate for maximum normalized difference vegetation index (slope_NDVI max ), annual temperature (slope_AT), annual precipitation (slope_AP) and annual radiation (slope_ARad) to slope_Ratio SR , (d) longitude, latitude and elevation to the change rate for the ratio of actual to potential Shannon (slope_Ratio Shannon ), (e) MNDVI max , MAT, MAP and MARad to slope_Ratio Shannon , (f) slope_NDVI max , slope_AT, slope_AP and slope_ARad to slope_Ratio Shannon , (g) longitude, latitude and elevation to the change rate for the ratio of actual to potential Simpson (slope_Ratio Simpson ), (h) MNDVI max , MAT, MAP and MARad to slope_Ratio Simpson , (i) slope_NDVI max , slope_AT, slope_AP and slope_ARad to slope_Ratio Simpson , (j) longitude, latitude and elevation to the change rate for the ratio of actual to potential Pielou (slope_Ratio Pielou ), (k) MNDVI max , MAT, MAP and MARad to slope_Ratio Pielou and (l) slope_NDVI max , slope_AT, slope_AP and slope_ARad to slope_Ratio Pielou .